X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Fbtrfs%2Fextent-tree.c;h=7527523c2d2d851ce1200424dce799814ac5a1fa;hb=806638bce99f51deccbfedbe86ab3c5cf55a1d35;hp=c0bb6b9ac4c6b7af43430927826e670ef5cdcd11;hpb=d0c803c4049c5ca322d4795d8b74f28768603e0e;p=linux-2.6-omap-h63xx.git diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index c0bb6b9ac4c..7527523c2d2 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -19,6 +19,8 @@ #include #include #include +#include +#include "compat.h" #include "hash.h" #include "crc32c.h" #include "ctree.h" @@ -29,58 +31,198 @@ #include "locking.h" #include "ref-cache.h" -#define BLOCK_GROUP_DATA EXTENT_WRITEBACK -#define BLOCK_GROUP_METADATA EXTENT_UPTODATE -#define BLOCK_GROUP_SYSTEM EXTENT_NEW +#define PENDING_EXTENT_INSERT 0 +#define PENDING_EXTENT_DELETE 1 +#define PENDING_BACKREF_UPDATE 2 -#define BLOCK_GROUP_DIRTY EXTENT_DIRTY +struct pending_extent_op { + int type; + u64 bytenr; + u64 num_bytes; + u64 parent; + u64 orig_parent; + u64 generation; + u64 orig_generation; + int level; + struct list_head list; + int del; +}; + +static int finish_current_insert(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, int all); +static int del_pending_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, int all); +static int pin_down_bytes(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, int is_data); +static int update_block_group(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, int alloc, + int mark_free); + +static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits) +{ + return (cache->flags & bits) == bits; +} + +/* + * this adds the block group to the fs_info rb tree for the block group + * cache + */ +static int btrfs_add_block_group_cache(struct btrfs_fs_info *info, + struct btrfs_block_group_cache *block_group) +{ + struct rb_node **p; + struct rb_node *parent = NULL; + struct btrfs_block_group_cache *cache; + + spin_lock(&info->block_group_cache_lock); + p = &info->block_group_cache_tree.rb_node; + + while (*p) { + parent = *p; + cache = rb_entry(parent, struct btrfs_block_group_cache, + cache_node); + if (block_group->key.objectid < cache->key.objectid) { + p = &(*p)->rb_left; + } else if (block_group->key.objectid > cache->key.objectid) { + p = &(*p)->rb_right; + } else { + spin_unlock(&info->block_group_cache_lock); + return -EEXIST; + } + } + + rb_link_node(&block_group->cache_node, parent, p); + rb_insert_color(&block_group->cache_node, + &info->block_group_cache_tree); + spin_unlock(&info->block_group_cache_lock); + + return 0; +} -static int finish_current_insert(struct btrfs_trans_handle *trans, struct - btrfs_root *extent_root); -static int del_pending_extents(struct btrfs_trans_handle *trans, struct - btrfs_root *extent_root); +/* + * This will return the block group at or after bytenr if contains is 0, else + * it will return the block group that contains the bytenr + */ static struct btrfs_block_group_cache * -__btrfs_find_block_group(struct btrfs_root *root, - struct btrfs_block_group_cache *hint, - u64 search_start, int data, int owner); +block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr, + int contains) +{ + struct btrfs_block_group_cache *cache, *ret = NULL; + struct rb_node *n; + u64 end, start; + + spin_lock(&info->block_group_cache_lock); + n = info->block_group_cache_tree.rb_node; + + while (n) { + cache = rb_entry(n, struct btrfs_block_group_cache, + cache_node); + end = cache->key.objectid + cache->key.offset - 1; + start = cache->key.objectid; -void maybe_lock_mutex(struct btrfs_root *root) + if (bytenr < start) { + if (!contains && (!ret || start < ret->key.objectid)) + ret = cache; + n = n->rb_left; + } else if (bytenr > start) { + if (contains && bytenr <= end) { + ret = cache; + break; + } + n = n->rb_right; + } else { + ret = cache; + break; + } + } + if (ret) + atomic_inc(&ret->count); + spin_unlock(&info->block_group_cache_lock); + + return ret; +} + +/* + * this is only called by cache_block_group, since we could have freed extents + * we need to check the pinned_extents for any extents that can't be used yet + * since their free space will be released as soon as the transaction commits. + */ +static int add_new_free_space(struct btrfs_block_group_cache *block_group, + struct btrfs_fs_info *info, u64 start, u64 end) { - if (root != root->fs_info->extent_root && - root != root->fs_info->chunk_root && - root != root->fs_info->dev_root) { - mutex_lock(&root->fs_info->alloc_mutex); + u64 extent_start, extent_end, size; + int ret; + + mutex_lock(&info->pinned_mutex); + while (start < end) { + ret = find_first_extent_bit(&info->pinned_extents, start, + &extent_start, &extent_end, + EXTENT_DIRTY); + if (ret) + break; + + if (extent_start == start) { + start = extent_end + 1; + } else if (extent_start > start && extent_start < end) { + size = extent_start - start; + ret = btrfs_add_free_space(block_group, start, + size); + BUG_ON(ret); + start = extent_end + 1; + } else { + break; + } } + + if (start < end) { + size = end - start; + ret = btrfs_add_free_space(block_group, start, size); + BUG_ON(ret); + } + mutex_unlock(&info->pinned_mutex); + + return 0; } -void maybe_unlock_mutex(struct btrfs_root *root) +static int remove_sb_from_cache(struct btrfs_root *root, + struct btrfs_block_group_cache *cache) { - if (root != root->fs_info->extent_root && - root != root->fs_info->chunk_root && - root != root->fs_info->dev_root) { - mutex_unlock(&root->fs_info->alloc_mutex); + u64 bytenr; + u64 *logical; + int stripe_len; + int i, nr, ret; + + for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { + bytenr = btrfs_sb_offset(i); + ret = btrfs_rmap_block(&root->fs_info->mapping_tree, + cache->key.objectid, bytenr, 0, + &logical, &nr, &stripe_len); + BUG_ON(ret); + while (nr--) { + btrfs_remove_free_space(cache, logical[nr], + stripe_len); + } + kfree(logical); } + return 0; } static int cache_block_group(struct btrfs_root *root, struct btrfs_block_group_cache *block_group) { struct btrfs_path *path; - int ret; + int ret = 0; struct btrfs_key key; struct extent_buffer *leaf; - struct extent_io_tree *free_space_cache; int slot; - u64 last = 0; - u64 hole_size; - u64 first_free; - int found = 0; + u64 last; if (!block_group) return 0; root = root->fs_info->extent_root; - free_space_cache = &root->fs_info->free_space_cache; if (block_group->cached) return 0; @@ -96,236 +238,99 @@ static int cache_block_group(struct btrfs_root *root, * skip the locking here */ path->skip_locking = 1; - first_free = block_group->key.objectid; - key.objectid = block_group->key.objectid; + last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET); + key.objectid = last; key.offset = 0; btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) - return ret; - ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY); - if (ret < 0) - return ret; - if (ret == 0) { - leaf = path->nodes[0]; - btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); - if (key.objectid + key.offset > first_free) - first_free = key.objectid + key.offset; - } - while(1) { + goto err; + + while (1) { leaf = path->nodes[0]; slot = path->slots[0]; if (slot >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto err; - if (ret == 0) { + if (ret == 0) continue; - } else { + else break; - } } btrfs_item_key_to_cpu(leaf, &key, slot); - if (key.objectid < block_group->key.objectid) { + if (key.objectid < block_group->key.objectid) goto next; - } + if (key.objectid >= block_group->key.objectid + - block_group->key.offset) { + block_group->key.offset) break; - } if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) { - if (!found) { - last = first_free; - found = 1; - } - if (key.objectid > last) { - hole_size = key.objectid - last; - set_extent_dirty(free_space_cache, last, - last + hole_size - 1, - GFP_NOFS); - } + add_new_free_space(block_group, root->fs_info, last, + key.objectid); + last = key.objectid + key.offset; } next: path->slots[0]++; } - if (!found) - last = first_free; - if (block_group->key.objectid + - block_group->key.offset > last) { - hole_size = block_group->key.objectid + - block_group->key.offset - last; - set_extent_dirty(free_space_cache, last, - last + hole_size - 1, GFP_NOFS); - } + add_new_free_space(block_group, root->fs_info, last, + block_group->key.objectid + + block_group->key.offset); + + remove_sb_from_cache(root, block_group); block_group->cached = 1; + ret = 0; err: btrfs_free_path(path); - return 0; + return ret; } -struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct - btrfs_fs_info *info, - u64 bytenr) +/* + * return the block group that starts at or after bytenr + */ +static struct btrfs_block_group_cache * +btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr) { - struct extent_io_tree *block_group_cache; - struct btrfs_block_group_cache *block_group = NULL; - u64 ptr; - u64 start; - u64 end; - int ret; + struct btrfs_block_group_cache *cache; - bytenr = max_t(u64, bytenr, - BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE); - block_group_cache = &info->block_group_cache; - ret = find_first_extent_bit(block_group_cache, - bytenr, &start, &end, - BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA | - BLOCK_GROUP_SYSTEM); - if (ret) { - return NULL; - } - ret = get_state_private(block_group_cache, start, &ptr); - if (ret) - return NULL; + cache = block_group_cache_tree_search(info, bytenr, 0); - block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr; - return block_group; + return cache; } -struct btrfs_block_group_cache *btrfs_lookup_block_group(struct - btrfs_fs_info *info, - u64 bytenr) +/* + * return the block group that contains teh given bytenr + */ +struct btrfs_block_group_cache *btrfs_lookup_block_group( + struct btrfs_fs_info *info, + u64 bytenr) { - struct extent_io_tree *block_group_cache; - struct btrfs_block_group_cache *block_group = NULL; - u64 ptr; - u64 start; - u64 end; - int ret; + struct btrfs_block_group_cache *cache; - bytenr = max_t(u64, bytenr, - BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE); - block_group_cache = &info->block_group_cache; - ret = find_first_extent_bit(block_group_cache, - bytenr, &start, &end, - BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA | - BLOCK_GROUP_SYSTEM); - if (ret) { - return NULL; - } - ret = get_state_private(block_group_cache, start, &ptr); - if (ret) - return NULL; + cache = block_group_cache_tree_search(info, bytenr, 1); - block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr; - if (block_group->key.objectid <= bytenr && bytenr < - block_group->key.objectid + block_group->key.offset) - return block_group; - return NULL; + return cache; } -static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits) +static inline void put_block_group(struct btrfs_block_group_cache *cache) { - return (cache->flags & bits) == bits; + if (atomic_dec_and_test(&cache->count)) + kfree(cache); } -static int noinline find_search_start(struct btrfs_root *root, - struct btrfs_block_group_cache **cache_ret, - u64 *start_ret, u64 num, int data) +static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info, + u64 flags) { - int ret; - struct btrfs_block_group_cache *cache = *cache_ret; - struct extent_io_tree *free_space_cache; - struct extent_state *state; - u64 last; - u64 start = 0; - u64 cache_miss = 0; - u64 total_fs_bytes; - u64 search_start = *start_ret; - int wrapped = 0; - - WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex)); - total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy); - free_space_cache = &root->fs_info->free_space_cache; - - if (!cache) - goto out; - -again: - ret = cache_block_group(root, cache); - if (ret) { - goto out; - } - - last = max(search_start, cache->key.objectid); - if (!block_group_bits(cache, data) || cache->ro) - goto new_group; - - spin_lock_irq(&free_space_cache->lock); - state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY); - while(1) { - if (!state) { - if (!cache_miss) - cache_miss = last; - spin_unlock_irq(&free_space_cache->lock); - goto new_group; - } - - start = max(last, state->start); - last = state->end + 1; - if (last - start < num) { - do { - state = extent_state_next(state); - } while(state && !(state->state & EXTENT_DIRTY)); - continue; - } - spin_unlock_irq(&free_space_cache->lock); - if (cache->ro) { - goto new_group; - } - if (start + num > cache->key.objectid + cache->key.offset) - goto new_group; - if (!block_group_bits(cache, data)) { - printk("block group bits don't match %Lu %d\n", cache->flags, data); - } - *start_ret = start; - return 0; - } -out: - cache = btrfs_lookup_block_group(root->fs_info, search_start); - if (!cache) { - printk("Unable to find block group for %Lu\n", search_start); - WARN_ON(1); - } - return -ENOSPC; - -new_group: - last = cache->key.objectid + cache->key.offset; -wrapped: - cache = btrfs_lookup_first_block_group(root->fs_info, last); - if (!cache || cache->key.objectid >= total_fs_bytes) { -no_cache: - if (!wrapped) { - wrapped = 1; - last = search_start; - goto wrapped; - } - goto out; - } - if (cache_miss && !cache->cached) { - cache_block_group(root, cache); - last = cache_miss; - cache = btrfs_lookup_first_block_group(root->fs_info, last); + struct list_head *head = &info->space_info; + struct btrfs_space_info *found; + list_for_each_entry(found, head, list) { + if (found->flags == flags) + return found; } - cache_miss = 0; - cache = btrfs_find_block_group(root, cache, last, data, 0); - if (!cache) - goto no_cache; - *cache_ret = cache; - goto again; + return NULL; } static u64 div_factor(u64 num, int factor) @@ -337,103 +342,38 @@ static u64 div_factor(u64 num, int factor) return num; } -static int block_group_state_bits(u64 flags) -{ - int bits = 0; - if (flags & BTRFS_BLOCK_GROUP_DATA) - bits |= BLOCK_GROUP_DATA; - if (flags & BTRFS_BLOCK_GROUP_METADATA) - bits |= BLOCK_GROUP_METADATA; - if (flags & BTRFS_BLOCK_GROUP_SYSTEM) - bits |= BLOCK_GROUP_SYSTEM; - return bits; -} - -static struct btrfs_block_group_cache * -__btrfs_find_block_group(struct btrfs_root *root, - struct btrfs_block_group_cache *hint, - u64 search_start, int data, int owner) +u64 btrfs_find_block_group(struct btrfs_root *root, + u64 search_start, u64 search_hint, int owner) { struct btrfs_block_group_cache *cache; - struct extent_io_tree *block_group_cache; - struct btrfs_block_group_cache *found_group = NULL; - struct btrfs_fs_info *info = root->fs_info; u64 used; - u64 last = 0; - u64 start; - u64 end; - u64 free_check; - u64 ptr; - int bit; - int ret; + u64 last = max(search_hint, search_start); + u64 group_start = 0; int full_search = 0; - int factor = 10; + int factor = 9; int wrapped = 0; - - block_group_cache = &info->block_group_cache; - - if (data & BTRFS_BLOCK_GROUP_METADATA) - factor = 9; - - bit = block_group_state_bits(data); - - if (search_start) { - struct btrfs_block_group_cache *shint; - shint = btrfs_lookup_first_block_group(info, search_start); - if (shint && block_group_bits(shint, data) && !shint->ro) { - spin_lock(&shint->lock); - used = btrfs_block_group_used(&shint->item); - if (used + shint->pinned < - div_factor(shint->key.offset, factor)) { - spin_unlock(&shint->lock); - return shint; - } - spin_unlock(&shint->lock); - } - } - if (hint && !hint->ro && block_group_bits(hint, data)) { - spin_lock(&hint->lock); - used = btrfs_block_group_used(&hint->item); - if (used + hint->pinned < - div_factor(hint->key.offset, factor)) { - spin_unlock(&hint->lock); - return hint; - } - spin_unlock(&hint->lock); - last = hint->key.objectid + hint->key.offset; - } else { - if (hint) - last = max(hint->key.objectid, search_start); - else - last = search_start; - } again: - while(1) { - ret = find_first_extent_bit(block_group_cache, last, - &start, &end, bit); - if (ret) + while (1) { + cache = btrfs_lookup_first_block_group(root->fs_info, last); + if (!cache) break; - ret = get_state_private(block_group_cache, start, &ptr); - if (ret) { - last = end + 1; - continue; - } - - cache = (struct btrfs_block_group_cache *)(unsigned long)ptr; spin_lock(&cache->lock); last = cache->key.objectid + cache->key.offset; used = btrfs_block_group_used(&cache->item); - if (!cache->ro && block_group_bits(cache, data)) { - free_check = div_factor(cache->key.offset, factor); - if (used + cache->pinned < free_check) { - found_group = cache; + if ((full_search || !cache->ro) && + block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) { + if (used + cache->pinned + cache->reserved < + div_factor(cache->key.offset, factor)) { + group_start = cache->key.objectid; spin_unlock(&cache->lock); + put_block_group(cache); goto found; } } spin_unlock(&cache->lock); + put_block_group(cache); cond_resched(); } if (!wrapped) { @@ -448,134 +388,24 @@ again: goto again; } found: - return found_group; -} - -struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root, - struct btrfs_block_group_cache - *hint, u64 search_start, - int data, int owner) -{ - - struct btrfs_block_group_cache *ret; - ret = __btrfs_find_block_group(root, hint, search_start, data, owner); - return ret; -} -static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset) -{ - u32 high_crc = ~(u32)0; - u32 low_crc = ~(u32)0; - __le64 lenum; - lenum = cpu_to_le64(root_objectid); - high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum)); - lenum = cpu_to_le64(ref_generation); - low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum)); - if (owner >= BTRFS_FIRST_FREE_OBJECTID) { - lenum = cpu_to_le64(owner); - low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum)); - lenum = cpu_to_le64(owner_offset); - low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum)); - } - return ((u64)high_crc << 32) | (u64)low_crc; -} - -static int match_extent_ref(struct extent_buffer *leaf, - struct btrfs_extent_ref *disk_ref, - struct btrfs_extent_ref *cpu_ref) -{ - int ret; - int len; - - if (cpu_ref->objectid) - len = sizeof(*cpu_ref); - else - len = 2 * sizeof(u64); - ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref, - len); - return ret == 0; + return group_start; } /* simple helper to search for an existing extent at a given offset */ -int btrfs_lookup_extent(struct btrfs_root *root, struct btrfs_path *path, - u64 start, u64 len) +int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len) { int ret; struct btrfs_key key; + struct btrfs_path *path; - maybe_lock_mutex(root); + path = btrfs_alloc_path(); + BUG_ON(!path); key.objectid = start; key.offset = len; btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path, 0, 0); - maybe_unlock_mutex(root); - return ret; -} - -static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, u64 bytenr, - u64 root_objectid, - u64 ref_generation, u64 owner, - u64 owner_offset, int del) -{ - u64 hash; - struct btrfs_key key; - struct btrfs_key found_key; - struct btrfs_extent_ref ref; - struct extent_buffer *leaf; - struct btrfs_extent_ref *disk_ref; - int ret; - int ret2; - - btrfs_set_stack_ref_root(&ref, root_objectid); - btrfs_set_stack_ref_generation(&ref, ref_generation); - btrfs_set_stack_ref_objectid(&ref, owner); - btrfs_set_stack_ref_offset(&ref, owner_offset); - - hash = hash_extent_ref(root_objectid, ref_generation, owner, - owner_offset); - key.offset = hash; - key.objectid = bytenr; - key.type = BTRFS_EXTENT_REF_KEY; - - while (1) { - ret = btrfs_search_slot(trans, root, &key, path, - del ? -1 : 0, del); - if (ret < 0) - goto out; - leaf = path->nodes[0]; - if (ret != 0) { - u32 nritems = btrfs_header_nritems(leaf); - if (path->slots[0] >= nritems) { - ret2 = btrfs_next_leaf(root, path); - if (ret2) - goto out; - leaf = path->nodes[0]; - } - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); - if (found_key.objectid != bytenr || - found_key.type != BTRFS_EXTENT_REF_KEY) - goto out; - key.offset = found_key.offset; - if (del) { - btrfs_release_path(root, path); - continue; - } - } - disk_ref = btrfs_item_ptr(path->nodes[0], - path->slots[0], - struct btrfs_extent_ref); - if (match_extent_ref(path->nodes[0], disk_ref, &ref)) { - ret = 0; - goto out; - } - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); - key.offset = found_key.offset + 1; - btrfs_release_path(root, path); - } -out: + btrfs_free_path(path); return ret; } @@ -596,7 +426,7 @@ out: * File extents can be referenced by: * * - multiple snapshots, subvolumes, or different generations in one subvol - * - different files inside a single subvolume (in theory, not implemented yet) + * - different files inside a single subvolume * - different offsets inside a file (bookend extents in file.c) * * The extent ref structure has fields for: @@ -604,2699 +434,5260 @@ out: * - Objectid of the subvolume root * - Generation number of the tree holding the reference * - objectid of the file holding the reference - * - offset in the file corresponding to the key holding the reference + * - number of references holding by parent node (alway 1 for tree blocks) + * + * Btree leaf may hold multiple references to a file extent. In most cases, + * these references are from same file and the corresponding offsets inside + * the file are close together. * * When a file extent is allocated the fields are filled in: - * (root_key.objectid, trans->transid, inode objectid, offset in file) + * (root_key.objectid, trans->transid, inode objectid, 1) * * When a leaf is cow'd new references are added for every file extent found - * in the leaf. It looks the same as the create case, but trans->transid - * will be different when the block is cow'd. + * in the leaf. It looks similar to the create case, but trans->transid will + * be different when the block is cow'd. * - * (root_key.objectid, trans->transid, inode objectid, offset in file) + * (root_key.objectid, trans->transid, inode objectid, + * number of references in the leaf) * - * When a file extent is removed either during snapshot deletion or file - * truncation, the corresponding back reference is found - * by searching for: + * When a file extent is removed either during snapshot deletion or + * file truncation, we find the corresponding back reference and check + * the following fields: * * (btrfs_header_owner(leaf), btrfs_header_generation(leaf), - * inode objectid, offset in file) + * inode objectid) * * Btree extents can be referenced by: * * - Different subvolumes * - Different generations of the same subvolume * - * Storing sufficient information for a full reverse mapping of a btree - * block would require storing the lowest key of the block in the backref, - * and it would require updating that lowest key either before write out or - * every time it changed. Instead, the objectid of the lowest key is stored - * along with the level of the tree block. This provides a hint - * about where in the btree the block can be found. Searches through the - * btree only need to look for a pointer to that block, so they stop one - * level higher than the level recorded in the backref. - * - * Some btrees do not do reference counting on their extents. These - * include the extent tree and the tree of tree roots. Backrefs for these - * trees always have a generation of zero. - * * When a tree block is created, back references are inserted: * - * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid) + * (root->root_key.objectid, trans->transid, level, 1) * - * When a tree block is cow'd in a reference counted root, - * new back references are added for all the blocks it points to. - * These are of the form (trans->transid will have increased since creation): + * When a tree block is cow'd, new back references are added for all the + * blocks it points to. If the tree block isn't in reference counted root, + * the old back references are removed. These new back references are of + * the form (trans->transid will have increased since creation): * - * (root->root_key.objectid, trans->transid, level, lowest_key_objectid) + * (root->root_key.objectid, trans->transid, level, 1) * - * Because the lowest_key_objectid and the level are just hints - * they are not used when backrefs are deleted. When a backref is deleted: + * When a backref is in deleting, the following fields are checked: * * if backref was for a tree root: - * root_objectid = root->root_key.objectid + * (btrfs_header_owner(itself), btrfs_header_generation(itself), level) * else - * root_objectid = btrfs_header_owner(parent) + * (btrfs_header_owner(parent), btrfs_header_generation(parent), level) * - * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0) + * Back Reference Key composing: * - * Back Reference Key hashing: - * - * Back references have four fields, each 64 bits long. Unfortunately, - * This is hashed into a single 64 bit number and placed into the key offset. - * The key objectid corresponds to the first byte in the extent, and the - * key type is set to BTRFS_EXTENT_REF_KEY + * The key objectid corresponds to the first byte in the extent, the key + * type is set to BTRFS_EXTENT_REF_KEY, and the key offset is the first + * byte of parent extent. If a extent is tree root, the key offset is set + * to the key objectid. */ -int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, u64 bytenr, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset) + +static noinline int lookup_extent_backref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + u64 bytenr, u64 parent, + u64 ref_root, u64 ref_generation, + u64 owner_objectid, int del) { - u64 hash; struct btrfs_key key; - struct btrfs_extent_ref ref; - struct btrfs_extent_ref *disk_ref; + struct btrfs_extent_ref *ref; + struct extent_buffer *leaf; + u64 ref_objectid; int ret; - btrfs_set_stack_ref_root(&ref, root_objectid); - btrfs_set_stack_ref_generation(&ref, ref_generation); - btrfs_set_stack_ref_objectid(&ref, owner); - btrfs_set_stack_ref_offset(&ref, owner_offset); - - hash = hash_extent_ref(root_objectid, ref_generation, owner, - owner_offset); - key.offset = hash; key.objectid = bytenr; key.type = BTRFS_EXTENT_REF_KEY; + key.offset = parent; - ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref)); - while (ret == -EEXIST) { - disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], - struct btrfs_extent_ref); - if (match_extent_ref(path->nodes[0], disk_ref, &ref)) - goto out; - key.offset++; - btrfs_release_path(root, path); - ret = btrfs_insert_empty_item(trans, root, path, &key, - sizeof(ref)); - } - if (ret) + ret = btrfs_search_slot(trans, root, &key, path, del ? -1 : 0, 1); + if (ret < 0) goto out; - disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], - struct btrfs_extent_ref); - write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref, - sizeof(ref)); - btrfs_mark_buffer_dirty(path->nodes[0]); + if (ret > 0) { + ret = -ENOENT; + goto out; + } + + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref); + ref_objectid = btrfs_ref_objectid(leaf, ref); + if (btrfs_ref_root(leaf, ref) != ref_root || + btrfs_ref_generation(leaf, ref) != ref_generation || + (ref_objectid != owner_objectid && + ref_objectid != BTRFS_MULTIPLE_OBJECTIDS)) { + ret = -EIO; + WARN_ON(1); + goto out; + } + ret = 0; out: - btrfs_release_path(root, path); return ret; } -static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 bytenr, u64 num_bytes, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset) +/* + * updates all the backrefs that are pending on update_list for the + * extent_root + */ +static noinline int update_backrefs(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, + struct btrfs_path *path, + struct list_head *update_list) { - struct btrfs_path *path; - int ret; struct btrfs_key key; - struct extent_buffer *l; - struct btrfs_extent_item *item; - u32 refs; - - WARN_ON(num_bytes < root->sectorsize); - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; + struct btrfs_extent_ref *ref; + struct btrfs_fs_info *info = extent_root->fs_info; + struct pending_extent_op *op; + struct extent_buffer *leaf; + int ret = 0; + struct list_head *cur = update_list->next; + u64 ref_objectid; + u64 ref_root = extent_root->root_key.objectid; - path->reada = 1; - key.objectid = bytenr; - btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); - key.offset = num_bytes; - ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, - 0, 1); - if (ret < 0) - return ret; - if (ret != 0) { - BUG(); - } - BUG_ON(ret != 0); - l = path->nodes[0]; - item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); - refs = btrfs_extent_refs(l, item); - btrfs_set_extent_refs(l, item, refs + 1); - btrfs_mark_buffer_dirty(path->nodes[0]); + op = list_entry(cur, struct pending_extent_op, list); - btrfs_release_path(root->fs_info->extent_root, path); +search: + key.objectid = op->bytenr; + key.type = BTRFS_EXTENT_REF_KEY; + key.offset = op->orig_parent; - path->reada = 1; - ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root, - path, bytenr, root_objectid, - ref_generation, owner, owner_offset); + ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 1); BUG_ON(ret); - finish_current_insert(trans, root->fs_info->extent_root); - del_pending_extents(trans, root->fs_info->extent_root); - btrfs_free_path(path); - return 0; -} + leaf = path->nodes[0]; -int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 bytenr, u64 num_bytes, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset) -{ - int ret; +loop: + ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref); + + ref_objectid = btrfs_ref_objectid(leaf, ref); + + if (btrfs_ref_root(leaf, ref) != ref_root || + btrfs_ref_generation(leaf, ref) != op->orig_generation || + (ref_objectid != op->level && + ref_objectid != BTRFS_MULTIPLE_OBJECTIDS)) { + printk(KERN_ERR "btrfs couldn't find %llu, parent %llu, " + "root %llu, owner %u\n", + (unsigned long long)op->bytenr, + (unsigned long long)op->orig_parent, + (unsigned long long)ref_root, op->level); + btrfs_print_leaf(extent_root, leaf); + BUG(); + } - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, - root_objectid, ref_generation, - owner, owner_offset); - mutex_unlock(&root->fs_info->alloc_mutex); - return ret; -} + key.objectid = op->bytenr; + key.offset = op->parent; + key.type = BTRFS_EXTENT_REF_KEY; + ret = btrfs_set_item_key_safe(trans, extent_root, path, &key); + BUG_ON(ret); + ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref); + btrfs_set_ref_generation(leaf, ref, op->generation); -int btrfs_extent_post_op(struct btrfs_trans_handle *trans, - struct btrfs_root *root) -{ - finish_current_insert(trans, root->fs_info->extent_root); - del_pending_extents(trans, root->fs_info->extent_root); - return 0; -} + cur = cur->next; -static int lookup_extent_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 bytenr, - u64 num_bytes, u32 *refs) -{ - struct btrfs_path *path; - int ret; - struct btrfs_key key; - struct extent_buffer *l; - struct btrfs_extent_item *item; + list_del_init(&op->list); + unlock_extent(&info->extent_ins, op->bytenr, + op->bytenr + op->num_bytes - 1, GFP_NOFS); + kfree(op); - WARN_ON(num_bytes < root->sectorsize); - path = btrfs_alloc_path(); - path->reada = 1; - key.objectid = bytenr; - key.offset = num_bytes; - btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); - ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, - 0, 0); - if (ret < 0) + if (cur == update_list) { + btrfs_mark_buffer_dirty(path->nodes[0]); + btrfs_release_path(extent_root, path); goto out; - if (ret != 0) { - btrfs_print_leaf(root, path->nodes[0]); - printk("failed to find block number %Lu\n", bytenr); - BUG(); } - l = path->nodes[0]; - item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); - *refs = btrfs_extent_refs(l, item); + + op = list_entry(cur, struct pending_extent_op, list); + + path->slots[0]++; + while (path->slots[0] < btrfs_header_nritems(leaf)) { + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + if (key.objectid == op->bytenr && + key.type == BTRFS_EXTENT_REF_KEY) + goto loop; + path->slots[0]++; + } + + btrfs_mark_buffer_dirty(path->nodes[0]); + btrfs_release_path(extent_root, path); + goto search; + out: - btrfs_free_path(path); return 0; } - -static int get_reference_status(struct btrfs_root *root, u64 bytenr, - u64 parent_gen, u64 ref_objectid, - u64 *min_generation, u32 *ref_count) +static noinline int insert_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, + struct btrfs_path *path, + struct list_head *insert_list, int nr) { - struct btrfs_root *extent_root = root->fs_info->extent_root; - struct btrfs_path *path; + struct btrfs_key *keys; + u32 *data_size; + struct pending_extent_op *op; struct extent_buffer *leaf; - struct btrfs_extent_ref *ref_item; - struct btrfs_key key; - struct btrfs_key found_key; - u64 root_objectid = root->root_key.objectid; - u64 ref_generation; - u32 nritems; - int ret; + struct list_head *cur = insert_list->next; + struct btrfs_fs_info *info = extent_root->fs_info; + u64 ref_root = extent_root->root_key.objectid; + int i = 0, last = 0, ret; + int total = nr * 2; - key.objectid = bytenr; - key.offset = 0; - key.type = BTRFS_EXTENT_ITEM_KEY; + if (!nr) + return 0; - path = btrfs_alloc_path(); - mutex_lock(&root->fs_info->alloc_mutex); - ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); - if (ret < 0) - goto out; - BUG_ON(ret == 0); + keys = kzalloc(total * sizeof(struct btrfs_key), GFP_NOFS); + if (!keys) + return -ENOMEM; - leaf = path->nodes[0]; - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + data_size = kzalloc(total * sizeof(u32), GFP_NOFS); + if (!data_size) { + kfree(keys); + return -ENOMEM; + } - if (found_key.objectid != bytenr || - found_key.type != BTRFS_EXTENT_ITEM_KEY) { - ret = 1; - goto out; + list_for_each_entry(op, insert_list, list) { + keys[i].objectid = op->bytenr; + keys[i].offset = op->num_bytes; + keys[i].type = BTRFS_EXTENT_ITEM_KEY; + data_size[i] = sizeof(struct btrfs_extent_item); + i++; + + keys[i].objectid = op->bytenr; + keys[i].offset = op->parent; + keys[i].type = BTRFS_EXTENT_REF_KEY; + data_size[i] = sizeof(struct btrfs_extent_ref); + i++; } - *ref_count = 0; - *min_generation = (u64)-1; + op = list_entry(cur, struct pending_extent_op, list); + i = 0; + while (i < total) { + int c; + ret = btrfs_insert_some_items(trans, extent_root, path, + keys+i, data_size+i, total-i); + BUG_ON(ret < 0); + + if (last && ret > 1) + BUG(); - while (1) { leaf = path->nodes[0]; - nritems = btrfs_header_nritems(leaf); - if (path->slots[0] >= nritems) { - ret = btrfs_next_leaf(extent_root, path); - if (ret < 0) - goto out; - if (ret == 0) - continue; - break; - } - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); - if (found_key.objectid != bytenr) - break; + for (c = 0; c < ret; c++) { + int ref_first = keys[i].type == BTRFS_EXTENT_REF_KEY; - if (found_key.type != BTRFS_EXTENT_REF_KEY) { - path->slots[0]++; - continue; + /* + * if the first item we inserted was a backref, then + * the EXTENT_ITEM will be the odd c's, else it will + * be the even c's + */ + if ((ref_first && (c % 2)) || + (!ref_first && !(c % 2))) { + struct btrfs_extent_item *itm; + + itm = btrfs_item_ptr(leaf, path->slots[0] + c, + struct btrfs_extent_item); + btrfs_set_extent_refs(path->nodes[0], itm, 1); + op->del++; + } else { + struct btrfs_extent_ref *ref; + + ref = btrfs_item_ptr(leaf, path->slots[0] + c, + struct btrfs_extent_ref); + btrfs_set_ref_root(leaf, ref, ref_root); + btrfs_set_ref_generation(leaf, ref, + op->generation); + btrfs_set_ref_objectid(leaf, ref, op->level); + btrfs_set_ref_num_refs(leaf, ref, 1); + op->del++; + } + + /* + * using del to see when its ok to free up the + * pending_extent_op. In the case where we insert the + * last item on the list in order to help do batching + * we need to not free the extent op until we actually + * insert the extent_item + */ + if (op->del == 2) { + unlock_extent(&info->extent_ins, op->bytenr, + op->bytenr + op->num_bytes - 1, + GFP_NOFS); + cur = cur->next; + list_del_init(&op->list); + kfree(op); + if (cur != insert_list) + op = list_entry(cur, + struct pending_extent_op, + list); + } } + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(extent_root, path); - ref_item = btrfs_item_ptr(leaf, path->slots[0], - struct btrfs_extent_ref); - ref_generation = btrfs_ref_generation(leaf, ref_item); /* - * For (parent_gen > 0 && parent_gen > ref_gen): - * - * we reach here through the oldest root, therefore - * all other reference from same snapshot should have - * a larger generation. + * Ok backref's and items usually go right next to eachother, + * but if we could only insert 1 item that means that we + * inserted on the end of a leaf, and we have no idea what may + * be on the next leaf so we just play it safe. In order to + * try and help this case we insert the last thing on our + * insert list so hopefully it will end up being the last + * thing on the leaf and everything else will be before it, + * which will let us insert a whole bunch of items at the same + * time. */ - if ((root_objectid != btrfs_ref_root(leaf, ref_item)) || - (parent_gen > 0 && parent_gen > ref_generation) || - (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID && - ref_objectid != btrfs_ref_objectid(leaf, ref_item))) { - if (ref_count) - *ref_count = 2; - break; + if (ret == 1 && !last && (i + ret < total)) { + /* + * last: where we will pick up the next time around + * i: our current key to insert, will be total - 1 + * cur: the current op we are screwing with + * op: duh + */ + last = i + ret; + i = total - 1; + cur = insert_list->prev; + op = list_entry(cur, struct pending_extent_op, list); + } else if (last) { + /* + * ok we successfully inserted the last item on the + * list, lets reset everything + * + * i: our current key to insert, so where we left off + * last time + * last: done with this + * cur: the op we are messing with + * op: duh + * total: since we inserted the last key, we need to + * decrement total so we dont overflow + */ + i = last; + last = 0; + total--; + if (i < total) { + cur = insert_list->next; + op = list_entry(cur, struct pending_extent_op, + list); + } + } else { + i += ret; } - *ref_count = 1; - if (*min_generation > ref_generation) - *min_generation = ref_generation; - - path->slots[0]++; + cond_resched(); } ret = 0; -out: - mutex_unlock(&root->fs_info->alloc_mutex); - btrfs_free_path(path); + kfree(keys); + kfree(data_size); return ret; } -int btrfs_cross_ref_exists(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_key *key, u64 bytenr) +static noinline int insert_extent_backref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + u64 bytenr, u64 parent, + u64 ref_root, u64 ref_generation, + u64 owner_objectid) { - struct btrfs_root *old_root; - struct btrfs_path *path = NULL; - struct extent_buffer *eb; - struct btrfs_file_extent_item *item; - u64 ref_generation; - u64 min_generation; - u64 extent_start; - u32 ref_count; - int level; + struct btrfs_key key; + struct extent_buffer *leaf; + struct btrfs_extent_ref *ref; + u32 num_refs; int ret; - BUG_ON(trans == NULL); - BUG_ON(key->type != BTRFS_EXTENT_DATA_KEY); - ret = get_reference_status(root, bytenr, 0, key->objectid, - &min_generation, &ref_count); - if (ret) - return ret; + key.objectid = bytenr; + key.type = BTRFS_EXTENT_REF_KEY; + key.offset = parent; - if (ref_count != 1) - return 1; + ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*ref)); + if (ret == 0) { + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_extent_ref); + btrfs_set_ref_root(leaf, ref, ref_root); + btrfs_set_ref_generation(leaf, ref, ref_generation); + btrfs_set_ref_objectid(leaf, ref, owner_objectid); + btrfs_set_ref_num_refs(leaf, ref, 1); + } else if (ret == -EEXIST) { + u64 existing_owner; + BUG_ON(owner_objectid < BTRFS_FIRST_FREE_OBJECTID); + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_extent_ref); + if (btrfs_ref_root(leaf, ref) != ref_root || + btrfs_ref_generation(leaf, ref) != ref_generation) { + ret = -EIO; + WARN_ON(1); + goto out; + } - old_root = root->dirty_root->root; - ref_generation = old_root->root_key.offset; + num_refs = btrfs_ref_num_refs(leaf, ref); + BUG_ON(num_refs == 0); + btrfs_set_ref_num_refs(leaf, ref, num_refs + 1); - /* all references are created in running transaction */ - if (min_generation > ref_generation) { + existing_owner = btrfs_ref_objectid(leaf, ref); + if (existing_owner != owner_objectid && + existing_owner != BTRFS_MULTIPLE_OBJECTIDS) { + btrfs_set_ref_objectid(leaf, ref, + BTRFS_MULTIPLE_OBJECTIDS); + } ret = 0; + } else { goto out; } + btrfs_mark_buffer_dirty(path->nodes[0]); +out: + btrfs_release_path(root, path); + return ret; +} - path = btrfs_alloc_path(); - if (!path) { - ret = -ENOMEM; - goto out; - } - - path->skip_locking = 1; - /* if no item found, the extent is referenced by other snapshot */ - ret = btrfs_search_slot(NULL, old_root, key, path, 0, 0); - if (ret) - goto out; +static noinline int remove_extent_backref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path) +{ + struct extent_buffer *leaf; + struct btrfs_extent_ref *ref; + u32 num_refs; + int ret = 0; - eb = path->nodes[0]; - item = btrfs_item_ptr(eb, path->slots[0], - struct btrfs_file_extent_item); - if (btrfs_file_extent_type(eb, item) != BTRFS_FILE_EXTENT_REG || - btrfs_file_extent_disk_bytenr(eb, item) != bytenr) { - ret = 1; - goto out; + leaf = path->nodes[0]; + ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref); + num_refs = btrfs_ref_num_refs(leaf, ref); + BUG_ON(num_refs == 0); + num_refs -= 1; + if (num_refs == 0) { + ret = btrfs_del_item(trans, root, path); + } else { + btrfs_set_ref_num_refs(leaf, ref, num_refs); + btrfs_mark_buffer_dirty(leaf); } + btrfs_release_path(root, path); + return ret; +} - for (level = BTRFS_MAX_LEVEL - 1; level >= -1; level--) { - if (level >= 0) { - eb = path->nodes[level]; - if (!eb) - continue; - extent_start = eb->start; - } else - extent_start = bytenr; - - ret = get_reference_status(root, extent_start, ref_generation, - 0, &min_generation, &ref_count); - if (ret) - goto out; +#ifdef BIO_RW_DISCARD +static void btrfs_issue_discard(struct block_device *bdev, + u64 start, u64 len) +{ + blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL); +} +#endif - if (ref_count != 1) { - ret = 1; - goto out; +static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, + u64 num_bytes) +{ +#ifdef BIO_RW_DISCARD + int ret; + u64 map_length = num_bytes; + struct btrfs_multi_bio *multi = NULL; + + /* Tell the block device(s) that the sectors can be discarded */ + ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, + bytenr, &map_length, &multi, 0); + if (!ret) { + struct btrfs_bio_stripe *stripe = multi->stripes; + int i; + + if (map_length > num_bytes) + map_length = num_bytes; + + for (i = 0; i < multi->num_stripes; i++, stripe++) { + btrfs_issue_discard(stripe->dev->bdev, + stripe->physical, + map_length); } - if (level >= 0) - ref_generation = btrfs_header_generation(eb); + kfree(multi); } - ret = 0; -out: - if (path) - btrfs_free_path(path); + return ret; +#else + return 0; +#endif } -int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, - struct extent_buffer *buf, int cache_ref) +static noinline int free_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, + struct list_head *del_list) { - u64 bytenr; - u32 nritems; - struct btrfs_key key; - struct btrfs_file_extent_item *fi; - int i; - int level; - int ret; - int faili; - int nr_file_extents = 0; - - if (!root->ref_cows) - return 0; + struct btrfs_fs_info *info = extent_root->fs_info; + struct btrfs_path *path; + struct btrfs_key key, found_key; + struct extent_buffer *leaf; + struct list_head *cur; + struct pending_extent_op *op; + struct btrfs_extent_item *ei; + int ret, num_to_del, extent_slot = 0, found_extent = 0; + u32 refs; + u64 bytes_freed = 0; - level = btrfs_header_level(buf); - nritems = btrfs_header_nritems(buf); - for (i = 0; i < nritems; i++) { - cond_resched(); - if (level == 0) { - u64 disk_bytenr; - btrfs_item_key_to_cpu(buf, &key, i); - if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) - continue; - fi = btrfs_item_ptr(buf, i, - struct btrfs_file_extent_item); - if (btrfs_file_extent_type(buf, fi) == - BTRFS_FILE_EXTENT_INLINE) - continue; - disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); - if (disk_bytenr == 0) - continue; + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + path->reada = 1; - if (buf != root->commit_root) - nr_file_extents++; +search: + /* search for the backref for the current ref we want to delete */ + cur = del_list->next; + op = list_entry(cur, struct pending_extent_op, list); + ret = lookup_extent_backref(trans, extent_root, path, op->bytenr, + op->orig_parent, + extent_root->root_key.objectid, + op->orig_generation, op->level, 1); + if (ret) { + printk(KERN_ERR "btrfs unable to find backref byte nr %llu " + "root %llu gen %llu owner %u\n", + (unsigned long long)op->bytenr, + (unsigned long long)extent_root->root_key.objectid, + (unsigned long long)op->orig_generation, op->level); + btrfs_print_leaf(extent_root, path->nodes[0]); + WARN_ON(1); + goto out; + } - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_inc_extent_ref(trans, root, disk_bytenr, - btrfs_file_extent_disk_num_bytes(buf, fi), - root->root_key.objectid, trans->transid, - key.objectid, key.offset); - mutex_unlock(&root->fs_info->alloc_mutex); - if (ret) { - faili = i; - WARN_ON(1); - goto fail; - } - } else { - bytenr = btrfs_node_blockptr(buf, i); - btrfs_node_key_to_cpu(buf, &key, i); - - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_inc_extent_ref(trans, root, bytenr, - btrfs_level_size(root, level - 1), - root->root_key.objectid, - trans->transid, - level - 1, key.objectid); - mutex_unlock(&root->fs_info->alloc_mutex); - if (ret) { - faili = i; - WARN_ON(1); - goto fail; - } + extent_slot = path->slots[0]; + num_to_del = 1; + found_extent = 0; + + /* + * if we aren't the first item on the leaf we can move back one and see + * if our ref is right next to our extent item + */ + if (likely(extent_slot)) { + extent_slot--; + btrfs_item_key_to_cpu(path->nodes[0], &found_key, + extent_slot); + if (found_key.objectid == op->bytenr && + found_key.type == BTRFS_EXTENT_ITEM_KEY && + found_key.offset == op->num_bytes) { + num_to_del++; + found_extent = 1; } } - /* cache orignal leaf block's references */ - if (level == 0 && cache_ref && buf != root->commit_root) { - struct btrfs_leaf_ref *ref; - struct btrfs_extent_info *info; - ref = btrfs_alloc_leaf_ref(root, nr_file_extents); - if (!ref) { - WARN_ON(1); - goto out; + /* + * if we didn't find the extent we need to delete the backref and then + * search for the extent item key so we can update its ref count + */ + if (!found_extent) { + key.objectid = op->bytenr; + key.type = BTRFS_EXTENT_ITEM_KEY; + key.offset = op->num_bytes; + + ret = remove_extent_backref(trans, extent_root, path); + BUG_ON(ret); + btrfs_release_path(extent_root, path); + ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); + BUG_ON(ret); + extent_slot = path->slots[0]; + } + + /* this is where we update the ref count for the extent */ + leaf = path->nodes[0]; + ei = btrfs_item_ptr(leaf, extent_slot, struct btrfs_extent_item); + refs = btrfs_extent_refs(leaf, ei); + BUG_ON(refs == 0); + refs--; + btrfs_set_extent_refs(leaf, ei, refs); + + btrfs_mark_buffer_dirty(leaf); + + /* + * This extent needs deleting. The reason cur_slot is extent_slot + + * num_to_del is because extent_slot points to the slot where the extent + * is, and if the backref was not right next to the extent we will be + * deleting at least 1 item, and will want to start searching at the + * slot directly next to extent_slot. However if we did find the + * backref next to the extent item them we will be deleting at least 2 + * items and will want to start searching directly after the ref slot + */ + if (!refs) { + struct list_head *pos, *n, *end; + int cur_slot = extent_slot+num_to_del; + u64 super_used; + u64 root_used; + + path->slots[0] = extent_slot; + bytes_freed = op->num_bytes; + + mutex_lock(&info->pinned_mutex); + ret = pin_down_bytes(trans, extent_root, op->bytenr, + op->num_bytes, op->level >= + BTRFS_FIRST_FREE_OBJECTID); + mutex_unlock(&info->pinned_mutex); + BUG_ON(ret < 0); + op->del = ret; + + /* + * we need to see if we can delete multiple things at once, so + * start looping through the list of extents we are wanting to + * delete and see if their extent/backref's are right next to + * eachother and the extents only have 1 ref + */ + for (pos = cur->next; pos != del_list; pos = pos->next) { + struct pending_extent_op *tmp; + + tmp = list_entry(pos, struct pending_extent_op, list); + + /* we only want to delete extent+ref at this stage */ + if (cur_slot >= btrfs_header_nritems(leaf) - 1) + break; + + btrfs_item_key_to_cpu(leaf, &found_key, cur_slot); + if (found_key.objectid != tmp->bytenr || + found_key.type != BTRFS_EXTENT_ITEM_KEY || + found_key.offset != tmp->num_bytes) + break; + + /* check to make sure this extent only has one ref */ + ei = btrfs_item_ptr(leaf, cur_slot, + struct btrfs_extent_item); + if (btrfs_extent_refs(leaf, ei) != 1) + break; + + btrfs_item_key_to_cpu(leaf, &found_key, cur_slot+1); + if (found_key.objectid != tmp->bytenr || + found_key.type != BTRFS_EXTENT_REF_KEY || + found_key.offset != tmp->orig_parent) + break; + + /* + * the ref is right next to the extent, we can set the + * ref count to 0 since we will delete them both now + */ + btrfs_set_extent_refs(leaf, ei, 0); + + /* pin down the bytes for this extent */ + mutex_lock(&info->pinned_mutex); + ret = pin_down_bytes(trans, extent_root, tmp->bytenr, + tmp->num_bytes, tmp->level >= + BTRFS_FIRST_FREE_OBJECTID); + mutex_unlock(&info->pinned_mutex); + BUG_ON(ret < 0); + + /* + * use the del field to tell if we need to go ahead and + * free up the extent when we delete the item or not. + */ + tmp->del = ret; + bytes_freed += tmp->num_bytes; + + num_to_del += 2; + cur_slot += 2; } + end = pos; - ref->root_gen = root->root_key.offset; - ref->bytenr = buf->start; - ref->owner = btrfs_header_owner(buf); - ref->generation = btrfs_header_generation(buf); - ref->nritems = nr_file_extents; - info = ref->extents; + /* update the free space counters */ + spin_lock(&info->delalloc_lock); + super_used = btrfs_super_bytes_used(&info->super_copy); + btrfs_set_super_bytes_used(&info->super_copy, + super_used - bytes_freed); - for (i = 0; nr_file_extents > 0 && i < nritems; i++) { - u64 disk_bytenr; - btrfs_item_key_to_cpu(buf, &key, i); - if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) - continue; - fi = btrfs_item_ptr(buf, i, - struct btrfs_file_extent_item); - if (btrfs_file_extent_type(buf, fi) == - BTRFS_FILE_EXTENT_INLINE) - continue; - disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); - if (disk_bytenr == 0) - continue; + root_used = btrfs_root_used(&extent_root->root_item); + btrfs_set_root_used(&extent_root->root_item, + root_used - bytes_freed); + spin_unlock(&info->delalloc_lock); - info->bytenr = disk_bytenr; - info->num_bytes = - btrfs_file_extent_disk_num_bytes(buf, fi); - info->objectid = key.objectid; - info->offset = key.offset; - info++; + /* delete the items */ + ret = btrfs_del_items(trans, extent_root, path, + path->slots[0], num_to_del); + BUG_ON(ret); + + /* + * loop through the extents we deleted and do the cleanup work + * on them + */ + for (pos = cur, n = pos->next; pos != end; + pos = n, n = pos->next) { + struct pending_extent_op *tmp; + tmp = list_entry(pos, struct pending_extent_op, list); + + /* + * remember tmp->del tells us wether or not we pinned + * down the extent + */ + ret = update_block_group(trans, extent_root, + tmp->bytenr, tmp->num_bytes, 0, + tmp->del); + BUG_ON(ret); + + list_del_init(&tmp->list); + unlock_extent(&info->extent_ins, tmp->bytenr, + tmp->bytenr + tmp->num_bytes - 1, + GFP_NOFS); + kfree(tmp); } + } else if (refs && found_extent) { + /* + * the ref and extent were right next to eachother, but the + * extent still has a ref, so just free the backref and keep + * going + */ + ret = remove_extent_backref(trans, extent_root, path); + BUG_ON(ret); - BUG_ON(!root->ref_tree); - ret = btrfs_add_leaf_ref(root, ref); - WARN_ON(ret); - btrfs_free_leaf_ref(root, ref); + list_del_init(&op->list); + unlock_extent(&info->extent_ins, op->bytenr, + op->bytenr + op->num_bytes - 1, GFP_NOFS); + kfree(op); + } else { + /* + * the extent has multiple refs and the backref we were looking + * for was not right next to it, so just unlock and go next, + * we're good to go + */ + list_del_init(&op->list); + unlock_extent(&info->extent_ins, op->bytenr, + op->bytenr + op->num_bytes - 1, GFP_NOFS); + kfree(op); } + + btrfs_release_path(extent_root, path); + if (!list_empty(del_list)) + goto search; + out: - return 0; -fail: - WARN_ON(1); -#if 0 - for (i =0; i < faili; i++) { - if (level == 0) { - u64 disk_bytenr; - btrfs_item_key_to_cpu(buf, &key, i); - if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) - continue; - fi = btrfs_item_ptr(buf, i, - struct btrfs_file_extent_item); - if (btrfs_file_extent_type(buf, fi) == - BTRFS_FILE_EXTENT_INLINE) - continue; - disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); - if (disk_bytenr == 0) - continue; - err = btrfs_free_extent(trans, root, disk_bytenr, - btrfs_file_extent_disk_num_bytes(buf, - fi), 0); - BUG_ON(err); - } else { - bytenr = btrfs_node_blockptr(buf, i); - err = btrfs_free_extent(trans, root, bytenr, - btrfs_level_size(root, level - 1), 0); - BUG_ON(err); - } - } -#endif + btrfs_free_path(path); return ret; } -static int write_one_cache_group(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, - struct btrfs_block_group_cache *cache) +static int __btrfs_update_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 orig_parent, u64 parent, + u64 orig_root, u64 ref_root, + u64 orig_generation, u64 ref_generation, + u64 owner_objectid) { int ret; - int pending_ret; struct btrfs_root *extent_root = root->fs_info->extent_root; - unsigned long bi; - struct extent_buffer *leaf; + struct btrfs_path *path; - ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); - if (ret < 0) - goto fail; - BUG_ON(ret); + if (root == root->fs_info->extent_root) { + struct pending_extent_op *extent_op; + u64 num_bytes; + + BUG_ON(owner_objectid >= BTRFS_MAX_LEVEL); + num_bytes = btrfs_level_size(root, (int)owner_objectid); + mutex_lock(&root->fs_info->extent_ins_mutex); + if (test_range_bit(&root->fs_info->extent_ins, bytenr, + bytenr + num_bytes - 1, EXTENT_WRITEBACK, 0)) { + u64 priv; + ret = get_state_private(&root->fs_info->extent_ins, + bytenr, &priv); + BUG_ON(ret); + extent_op = (struct pending_extent_op *) + (unsigned long)priv; + BUG_ON(extent_op->parent != orig_parent); + BUG_ON(extent_op->generation != orig_generation); - leaf = path->nodes[0]; - bi = btrfs_item_ptr_offset(leaf, path->slots[0]); - write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item)); - btrfs_mark_buffer_dirty(leaf); - btrfs_release_path(extent_root, path); -fail: - finish_current_insert(trans, extent_root); - pending_ret = del_pending_extents(trans, extent_root); - if (ret) - return ret; - if (pending_ret) - return pending_ret; - return 0; + extent_op->parent = parent; + extent_op->generation = ref_generation; + } else { + extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); + BUG_ON(!extent_op); + + extent_op->type = PENDING_BACKREF_UPDATE; + extent_op->bytenr = bytenr; + extent_op->num_bytes = num_bytes; + extent_op->parent = parent; + extent_op->orig_parent = orig_parent; + extent_op->generation = ref_generation; + extent_op->orig_generation = orig_generation; + extent_op->level = (int)owner_objectid; + INIT_LIST_HEAD(&extent_op->list); + extent_op->del = 0; + + set_extent_bits(&root->fs_info->extent_ins, + bytenr, bytenr + num_bytes - 1, + EXTENT_WRITEBACK, GFP_NOFS); + set_state_private(&root->fs_info->extent_ins, + bytenr, (unsigned long)extent_op); + } + mutex_unlock(&root->fs_info->extent_ins_mutex); + return 0; + } + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + ret = lookup_extent_backref(trans, extent_root, path, + bytenr, orig_parent, orig_root, + orig_generation, owner_objectid, 1); + if (ret) + goto out; + ret = remove_extent_backref(trans, extent_root, path); + if (ret) + goto out; + ret = insert_extent_backref(trans, extent_root, path, bytenr, + parent, ref_root, ref_generation, + owner_objectid); + BUG_ON(ret); + finish_current_insert(trans, extent_root, 0); + del_pending_extents(trans, extent_root, 0); +out: + btrfs_free_path(path); + return ret; } -int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, - struct btrfs_root *root) +int btrfs_update_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 orig_parent, u64 parent, + u64 ref_root, u64 ref_generation, + u64 owner_objectid) { - struct extent_io_tree *block_group_cache; - struct btrfs_block_group_cache *cache; int ret; - int err = 0; - int werr = 0; + if (ref_root == BTRFS_TREE_LOG_OBJECTID && + owner_objectid < BTRFS_FIRST_FREE_OBJECTID) + return 0; + ret = __btrfs_update_extent_ref(trans, root, bytenr, orig_parent, + parent, ref_root, ref_root, + ref_generation, ref_generation, + owner_objectid); + return ret; +} + +static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 orig_parent, u64 parent, + u64 orig_root, u64 ref_root, + u64 orig_generation, u64 ref_generation, + u64 owner_objectid) +{ struct btrfs_path *path; - u64 last = 0; - u64 start; - u64 end; - u64 ptr; + int ret; + struct btrfs_key key; + struct extent_buffer *l; + struct btrfs_extent_item *item; + u32 refs; - block_group_cache = &root->fs_info->block_group_cache; path = btrfs_alloc_path(); if (!path) return -ENOMEM; - mutex_lock(&root->fs_info->alloc_mutex); - while(1) { - ret = find_first_extent_bit(block_group_cache, last, - &start, &end, BLOCK_GROUP_DIRTY); - if (ret) - break; + path->reada = 1; + key.objectid = bytenr; + key.type = BTRFS_EXTENT_ITEM_KEY; + key.offset = (u64)-1; - last = end + 1; - ret = get_state_private(block_group_cache, start, &ptr); - if (ret) - break; - cache = (struct btrfs_block_group_cache *)(unsigned long)ptr; - err = write_one_cache_group(trans, root, - path, cache); - /* - * if we fail to write the cache group, we want - * to keep it marked dirty in hopes that a later - * write will work - */ - if (err) { - werr = err; - continue; - } - clear_extent_bits(block_group_cache, start, end, - BLOCK_GROUP_DIRTY, GFP_NOFS); + ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, + 0, 1); + if (ret < 0) + return ret; + BUG_ON(ret == 0 || path->slots[0] == 0); + + path->slots[0]--; + l = path->nodes[0]; + + btrfs_item_key_to_cpu(l, &key, path->slots[0]); + if (key.objectid != bytenr) { + btrfs_print_leaf(root->fs_info->extent_root, path->nodes[0]); + printk(KERN_ERR "btrfs wanted %llu found %llu\n", + (unsigned long long)bytenr, + (unsigned long long)key.objectid); + BUG(); } + BUG_ON(key.type != BTRFS_EXTENT_ITEM_KEY); + + item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); + refs = btrfs_extent_refs(l, item); + btrfs_set_extent_refs(l, item, refs + 1); + btrfs_mark_buffer_dirty(path->nodes[0]); + + btrfs_release_path(root->fs_info->extent_root, path); + + path->reada = 1; + ret = insert_extent_backref(trans, root->fs_info->extent_root, + path, bytenr, parent, + ref_root, ref_generation, + owner_objectid); + BUG_ON(ret); + finish_current_insert(trans, root->fs_info->extent_root, 0); + del_pending_extents(trans, root->fs_info->extent_root, 0); + btrfs_free_path(path); - mutex_unlock(&root->fs_info->alloc_mutex); - return werr; + return 0; } -static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info, - u64 flags) +int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, u64 parent, + u64 ref_root, u64 ref_generation, + u64 owner_objectid) +{ + int ret; + if (ref_root == BTRFS_TREE_LOG_OBJECTID && + owner_objectid < BTRFS_FIRST_FREE_OBJECTID) + return 0; + ret = __btrfs_inc_extent_ref(trans, root, bytenr, 0, parent, + 0, ref_root, 0, ref_generation, + owner_objectid); + return ret; +} + +int btrfs_extent_post_op(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + finish_current_insert(trans, root->fs_info->extent_root, 1); + del_pending_extents(trans, root->fs_info->extent_root, 1); + return 0; +} + +int btrfs_lookup_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 bytenr, + u64 num_bytes, u32 *refs) +{ + struct btrfs_path *path; + int ret; + struct btrfs_key key; + struct extent_buffer *l; + struct btrfs_extent_item *item; + + WARN_ON(num_bytes < root->sectorsize); + path = btrfs_alloc_path(); + path->reada = 1; + key.objectid = bytenr; + key.offset = num_bytes; + btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); + ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path, + 0, 0); + if (ret < 0) + goto out; + if (ret != 0) { + btrfs_print_leaf(root, path->nodes[0]); + printk(KERN_INFO "btrfs failed to find block number %llu\n", + (unsigned long long)bytenr); + BUG(); + } + l = path->nodes[0]; + item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item); + *refs = btrfs_extent_refs(l, item); +out: + btrfs_free_path(path); + return 0; +} + +int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 objectid, u64 bytenr) +{ + struct btrfs_root *extent_root = root->fs_info->extent_root; + struct btrfs_path *path; + struct extent_buffer *leaf; + struct btrfs_extent_ref *ref_item; + struct btrfs_key key; + struct btrfs_key found_key; + u64 ref_root; + u64 last_snapshot; + u32 nritems; + int ret; + + key.objectid = bytenr; + key.offset = (u64)-1; + key.type = BTRFS_EXTENT_ITEM_KEY; + + path = btrfs_alloc_path(); + ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); + if (ret < 0) + goto out; + BUG_ON(ret == 0); + + ret = -ENOENT; + if (path->slots[0] == 0) + goto out; + + path->slots[0]--; + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + + if (found_key.objectid != bytenr || + found_key.type != BTRFS_EXTENT_ITEM_KEY) + goto out; + + last_snapshot = btrfs_root_last_snapshot(&root->root_item); + while (1) { + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + if (path->slots[0] >= nritems) { + ret = btrfs_next_leaf(extent_root, path); + if (ret < 0) + goto out; + if (ret == 0) + continue; + break; + } + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != bytenr) + break; + + if (found_key.type != BTRFS_EXTENT_REF_KEY) { + path->slots[0]++; + continue; + } + + ref_item = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_extent_ref); + ref_root = btrfs_ref_root(leaf, ref_item); + if ((ref_root != root->root_key.objectid && + ref_root != BTRFS_TREE_LOG_OBJECTID) || + objectid != btrfs_ref_objectid(leaf, ref_item)) { + ret = 1; + goto out; + } + if (btrfs_ref_generation(leaf, ref_item) <= last_snapshot) { + ret = 1; + goto out; + } + + path->slots[0]++; + } + ret = 0; +out: + btrfs_free_path(path); + return ret; +} + +int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, + struct extent_buffer *buf, u32 nr_extents) +{ + struct btrfs_key key; + struct btrfs_file_extent_item *fi; + u64 root_gen; + u32 nritems; + int i; + int level; + int ret = 0; + int shared = 0; + + if (!root->ref_cows) + return 0; + + if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { + shared = 0; + root_gen = root->root_key.offset; + } else { + shared = 1; + root_gen = trans->transid - 1; + } + + level = btrfs_header_level(buf); + nritems = btrfs_header_nritems(buf); + + if (level == 0) { + struct btrfs_leaf_ref *ref; + struct btrfs_extent_info *info; + + ref = btrfs_alloc_leaf_ref(root, nr_extents); + if (!ref) { + ret = -ENOMEM; + goto out; + } + + ref->root_gen = root_gen; + ref->bytenr = buf->start; + ref->owner = btrfs_header_owner(buf); + ref->generation = btrfs_header_generation(buf); + ref->nritems = nr_extents; + info = ref->extents; + + for (i = 0; nr_extents > 0 && i < nritems; i++) { + u64 disk_bytenr; + btrfs_item_key_to_cpu(buf, &key, i); + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(buf, i, + struct btrfs_file_extent_item); + if (btrfs_file_extent_type(buf, fi) == + BTRFS_FILE_EXTENT_INLINE) + continue; + disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi); + if (disk_bytenr == 0) + continue; + + info->bytenr = disk_bytenr; + info->num_bytes = + btrfs_file_extent_disk_num_bytes(buf, fi); + info->objectid = key.objectid; + info->offset = key.offset; + info++; + } + + ret = btrfs_add_leaf_ref(root, ref, shared); + if (ret == -EEXIST && shared) { + struct btrfs_leaf_ref *old; + old = btrfs_lookup_leaf_ref(root, ref->bytenr); + BUG_ON(!old); + btrfs_remove_leaf_ref(root, old); + btrfs_free_leaf_ref(root, old); + ret = btrfs_add_leaf_ref(root, ref, shared); + } + WARN_ON(ret); + btrfs_free_leaf_ref(root, ref); + } +out: + return ret; +} + +/* when a block goes through cow, we update the reference counts of + * everything that block points to. The internal pointers of the block + * can be in just about any order, and it is likely to have clusters of + * things that are close together and clusters of things that are not. + * + * To help reduce the seeks that come with updating all of these reference + * counts, sort them by byte number before actual updates are done. + * + * struct refsort is used to match byte number to slot in the btree block. + * we sort based on the byte number and then use the slot to actually + * find the item. + * + * struct refsort is smaller than strcut btrfs_item and smaller than + * struct btrfs_key_ptr. Since we're currently limited to the page size + * for a btree block, there's no way for a kmalloc of refsorts for a + * single node to be bigger than a page. + */ +struct refsort { + u64 bytenr; + u32 slot; +}; + +/* + * for passing into sort() + */ +static int refsort_cmp(const void *a_void, const void *b_void) +{ + const struct refsort *a = a_void; + const struct refsort *b = b_void; + + if (a->bytenr < b->bytenr) + return -1; + if (a->bytenr > b->bytenr) + return 1; + return 0; +} + + +noinline int btrfs_inc_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *orig_buf, + struct extent_buffer *buf, u32 *nr_extents) +{ + u64 bytenr; + u64 ref_root; + u64 orig_root; + u64 ref_generation; + u64 orig_generation; + struct refsort *sorted; + u32 nritems; + u32 nr_file_extents = 0; + struct btrfs_key key; + struct btrfs_file_extent_item *fi; + int i; + int level; + int ret = 0; + int faili = 0; + int refi = 0; + int slot; + int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *, + u64, u64, u64, u64, u64, u64, u64, u64); + + ref_root = btrfs_header_owner(buf); + ref_generation = btrfs_header_generation(buf); + orig_root = btrfs_header_owner(orig_buf); + orig_generation = btrfs_header_generation(orig_buf); + + nritems = btrfs_header_nritems(buf); + level = btrfs_header_level(buf); + + sorted = kmalloc(sizeof(struct refsort) * nritems, GFP_NOFS); + BUG_ON(!sorted); + + if (root->ref_cows) { + process_func = __btrfs_inc_extent_ref; + } else { + if (level == 0 && + root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) + goto out; + if (level != 0 && + root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) + goto out; + process_func = __btrfs_update_extent_ref; + } + + /* + * we make two passes through the items. In the first pass we + * only record the byte number and slot. Then we sort based on + * byte number and do the actual work based on the sorted results + */ + for (i = 0; i < nritems; i++) { + cond_resched(); + if (level == 0) { + btrfs_item_key_to_cpu(buf, &key, i); + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(buf, i, + struct btrfs_file_extent_item); + if (btrfs_file_extent_type(buf, fi) == + BTRFS_FILE_EXTENT_INLINE) + continue; + bytenr = btrfs_file_extent_disk_bytenr(buf, fi); + if (bytenr == 0) + continue; + + nr_file_extents++; + sorted[refi].bytenr = bytenr; + sorted[refi].slot = i; + refi++; + } else { + bytenr = btrfs_node_blockptr(buf, i); + sorted[refi].bytenr = bytenr; + sorted[refi].slot = i; + refi++; + } + } + /* + * if refi == 0, we didn't actually put anything into the sorted + * array and we're done + */ + if (refi == 0) + goto out; + + sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL); + + for (i = 0; i < refi; i++) { + cond_resched(); + slot = sorted[i].slot; + bytenr = sorted[i].bytenr; + + if (level == 0) { + btrfs_item_key_to_cpu(buf, &key, slot); + + ret = process_func(trans, root, bytenr, + orig_buf->start, buf->start, + orig_root, ref_root, + orig_generation, ref_generation, + key.objectid); + + if (ret) { + faili = slot; + WARN_ON(1); + goto fail; + } + } else { + ret = process_func(trans, root, bytenr, + orig_buf->start, buf->start, + orig_root, ref_root, + orig_generation, ref_generation, + level - 1); + if (ret) { + faili = slot; + WARN_ON(1); + goto fail; + } + } + } +out: + kfree(sorted); + if (nr_extents) { + if (level == 0) + *nr_extents = nr_file_extents; + else + *nr_extents = nritems; + } + return 0; +fail: + kfree(sorted); + WARN_ON(1); + return ret; +} + +int btrfs_update_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct extent_buffer *orig_buf, + struct extent_buffer *buf, int start_slot, int nr) + +{ + u64 bytenr; + u64 ref_root; + u64 orig_root; + u64 ref_generation; + u64 orig_generation; + struct btrfs_key key; + struct btrfs_file_extent_item *fi; + int i; + int ret; + int slot; + int level; + + BUG_ON(start_slot < 0); + BUG_ON(start_slot + nr > btrfs_header_nritems(buf)); + + ref_root = btrfs_header_owner(buf); + ref_generation = btrfs_header_generation(buf); + orig_root = btrfs_header_owner(orig_buf); + orig_generation = btrfs_header_generation(orig_buf); + level = btrfs_header_level(buf); + + if (!root->ref_cows) { + if (level == 0 && + root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) + return 0; + if (level != 0 && + root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) + return 0; + } + + for (i = 0, slot = start_slot; i < nr; i++, slot++) { + cond_resched(); + if (level == 0) { + btrfs_item_key_to_cpu(buf, &key, slot); + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(buf, slot, + struct btrfs_file_extent_item); + if (btrfs_file_extent_type(buf, fi) == + BTRFS_FILE_EXTENT_INLINE) + continue; + bytenr = btrfs_file_extent_disk_bytenr(buf, fi); + if (bytenr == 0) + continue; + ret = __btrfs_update_extent_ref(trans, root, bytenr, + orig_buf->start, buf->start, + orig_root, ref_root, + orig_generation, ref_generation, + key.objectid); + if (ret) + goto fail; + } else { + bytenr = btrfs_node_blockptr(buf, slot); + ret = __btrfs_update_extent_ref(trans, root, bytenr, + orig_buf->start, buf->start, + orig_root, ref_root, + orig_generation, ref_generation, + level - 1); + if (ret) + goto fail; + } + } + return 0; +fail: + WARN_ON(1); + return -1; +} + +static int write_one_cache_group(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_block_group_cache *cache) +{ + int ret; + int pending_ret; + struct btrfs_root *extent_root = root->fs_info->extent_root; + unsigned long bi; + struct extent_buffer *leaf; + + ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1); + if (ret < 0) + goto fail; + BUG_ON(ret); + + leaf = path->nodes[0]; + bi = btrfs_item_ptr_offset(leaf, path->slots[0]); + write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item)); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(extent_root, path); +fail: + finish_current_insert(trans, extent_root, 0); + pending_ret = del_pending_extents(trans, extent_root, 0); + if (ret) + return ret; + if (pending_ret) + return pending_ret; + return 0; + +} + +int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + struct btrfs_block_group_cache *cache, *entry; + struct rb_node *n; + int err = 0; + int werr = 0; + struct btrfs_path *path; + u64 last = 0; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + while (1) { + cache = NULL; + spin_lock(&root->fs_info->block_group_cache_lock); + for (n = rb_first(&root->fs_info->block_group_cache_tree); + n; n = rb_next(n)) { + entry = rb_entry(n, struct btrfs_block_group_cache, + cache_node); + if (entry->dirty) { + cache = entry; + break; + } + } + spin_unlock(&root->fs_info->block_group_cache_lock); + + if (!cache) + break; + + cache->dirty = 0; + last += cache->key.offset; + + err = write_one_cache_group(trans, root, + path, cache); + /* + * if we fail to write the cache group, we want + * to keep it marked dirty in hopes that a later + * write will work + */ + if (err) { + werr = err; + continue; + } + } + btrfs_free_path(path); + return werr; +} + +int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr) +{ + struct btrfs_block_group_cache *block_group; + int readonly = 0; + + block_group = btrfs_lookup_block_group(root->fs_info, bytenr); + if (!block_group || block_group->ro) + readonly = 1; + if (block_group) + put_block_group(block_group); + return readonly; +} + +static int update_space_info(struct btrfs_fs_info *info, u64 flags, + u64 total_bytes, u64 bytes_used, + struct btrfs_space_info **space_info) { - struct list_head *head = &info->space_info; - struct list_head *cur; struct btrfs_space_info *found; - list_for_each(cur, head) { - found = list_entry(cur, struct btrfs_space_info, list); - if (found->flags == flags) - return found; + + found = __find_space_info(info, flags); + if (found) { + spin_lock(&found->lock); + found->total_bytes += total_bytes; + found->bytes_used += bytes_used; + found->full = 0; + spin_unlock(&found->lock); + *space_info = found; + return 0; + } + found = kzalloc(sizeof(*found), GFP_NOFS); + if (!found) + return -ENOMEM; + + list_add(&found->list, &info->space_info); + INIT_LIST_HEAD(&found->block_groups); + init_rwsem(&found->groups_sem); + spin_lock_init(&found->lock); + found->flags = flags; + found->total_bytes = total_bytes; + found->bytes_used = bytes_used; + found->bytes_pinned = 0; + found->bytes_reserved = 0; + found->bytes_readonly = 0; + found->full = 0; + found->force_alloc = 0; + *space_info = found; + return 0; +} + +static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) +{ + u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 | + BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_RAID10 | + BTRFS_BLOCK_GROUP_DUP); + if (extra_flags) { + if (flags & BTRFS_BLOCK_GROUP_DATA) + fs_info->avail_data_alloc_bits |= extra_flags; + if (flags & BTRFS_BLOCK_GROUP_METADATA) + fs_info->avail_metadata_alloc_bits |= extra_flags; + if (flags & BTRFS_BLOCK_GROUP_SYSTEM) + fs_info->avail_system_alloc_bits |= extra_flags; + } +} + +static void set_block_group_readonly(struct btrfs_block_group_cache *cache) +{ + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + if (!cache->ro) { + cache->space_info->bytes_readonly += cache->key.offset - + btrfs_block_group_used(&cache->item); + cache->ro = 1; + } + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); +} + +u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags) +{ + u64 num_devices = root->fs_info->fs_devices->rw_devices; + + if (num_devices == 1) + flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0); + if (num_devices < 4) + flags &= ~BTRFS_BLOCK_GROUP_RAID10; + + if ((flags & BTRFS_BLOCK_GROUP_DUP) && + (flags & (BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_RAID10))) { + flags &= ~BTRFS_BLOCK_GROUP_DUP; + } + + if ((flags & BTRFS_BLOCK_GROUP_RAID1) && + (flags & BTRFS_BLOCK_GROUP_RAID10)) { + flags &= ~BTRFS_BLOCK_GROUP_RAID1; + } + + if ((flags & BTRFS_BLOCK_GROUP_RAID0) && + ((flags & BTRFS_BLOCK_GROUP_RAID1) | + (flags & BTRFS_BLOCK_GROUP_RAID10) | + (flags & BTRFS_BLOCK_GROUP_DUP))) + flags &= ~BTRFS_BLOCK_GROUP_RAID0; + return flags; +} + +static int do_chunk_alloc(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, u64 alloc_bytes, + u64 flags, int force) +{ + struct btrfs_space_info *space_info; + u64 thresh; + int ret = 0; + + mutex_lock(&extent_root->fs_info->chunk_mutex); + + flags = btrfs_reduce_alloc_profile(extent_root, flags); + + space_info = __find_space_info(extent_root->fs_info, flags); + if (!space_info) { + ret = update_space_info(extent_root->fs_info, flags, + 0, 0, &space_info); + BUG_ON(ret); + } + BUG_ON(!space_info); + + spin_lock(&space_info->lock); + if (space_info->force_alloc) { + force = 1; + space_info->force_alloc = 0; + } + if (space_info->full) { + spin_unlock(&space_info->lock); + goto out; + } + + thresh = space_info->total_bytes - space_info->bytes_readonly; + thresh = div_factor(thresh, 6); + if (!force && + (space_info->bytes_used + space_info->bytes_pinned + + space_info->bytes_reserved + alloc_bytes) < thresh) { + spin_unlock(&space_info->lock); + goto out; + } + spin_unlock(&space_info->lock); + + ret = btrfs_alloc_chunk(trans, extent_root, flags); + if (ret) + space_info->full = 1; +out: + mutex_unlock(&extent_root->fs_info->chunk_mutex); + return ret; +} + +static int update_block_group(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, int alloc, + int mark_free) +{ + struct btrfs_block_group_cache *cache; + struct btrfs_fs_info *info = root->fs_info; + u64 total = num_bytes; + u64 old_val; + u64 byte_in_group; + + while (total) { + cache = btrfs_lookup_block_group(info, bytenr); + if (!cache) + return -1; + byte_in_group = bytenr - cache->key.objectid; + WARN_ON(byte_in_group > cache->key.offset); + + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + cache->dirty = 1; + old_val = btrfs_block_group_used(&cache->item); + num_bytes = min(total, cache->key.offset - byte_in_group); + if (alloc) { + old_val += num_bytes; + cache->space_info->bytes_used += num_bytes; + if (cache->ro) + cache->space_info->bytes_readonly -= num_bytes; + btrfs_set_block_group_used(&cache->item, old_val); + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + } else { + old_val -= num_bytes; + cache->space_info->bytes_used -= num_bytes; + if (cache->ro) + cache->space_info->bytes_readonly += num_bytes; + btrfs_set_block_group_used(&cache->item, old_val); + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + if (mark_free) { + int ret; + + ret = btrfs_discard_extent(root, bytenr, + num_bytes); + WARN_ON(ret); + + ret = btrfs_add_free_space(cache, bytenr, + num_bytes); + WARN_ON(ret); + } + } + put_block_group(cache); + total -= num_bytes; + bytenr += num_bytes; + } + return 0; +} + +static u64 first_logical_byte(struct btrfs_root *root, u64 search_start) +{ + struct btrfs_block_group_cache *cache; + u64 bytenr; + + cache = btrfs_lookup_first_block_group(root->fs_info, search_start); + if (!cache) + return 0; + + bytenr = cache->key.objectid; + put_block_group(cache); + + return bytenr; +} + +int btrfs_update_pinned_extents(struct btrfs_root *root, + u64 bytenr, u64 num, int pin) +{ + u64 len; + struct btrfs_block_group_cache *cache; + struct btrfs_fs_info *fs_info = root->fs_info; + + WARN_ON(!mutex_is_locked(&root->fs_info->pinned_mutex)); + if (pin) { + set_extent_dirty(&fs_info->pinned_extents, + bytenr, bytenr + num - 1, GFP_NOFS); + } else { + clear_extent_dirty(&fs_info->pinned_extents, + bytenr, bytenr + num - 1, GFP_NOFS); + } + while (num > 0) { + cache = btrfs_lookup_block_group(fs_info, bytenr); + BUG_ON(!cache); + len = min(num, cache->key.offset - + (bytenr - cache->key.objectid)); + if (pin) { + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + cache->pinned += len; + cache->space_info->bytes_pinned += len; + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + fs_info->total_pinned += len; + } else { + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + cache->pinned -= len; + cache->space_info->bytes_pinned -= len; + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + fs_info->total_pinned -= len; + if (cache->cached) + btrfs_add_free_space(cache, bytenr, len); + } + put_block_group(cache); + bytenr += len; + num -= len; + } + return 0; +} + +static int update_reserved_extents(struct btrfs_root *root, + u64 bytenr, u64 num, int reserve) +{ + u64 len; + struct btrfs_block_group_cache *cache; + struct btrfs_fs_info *fs_info = root->fs_info; + + while (num > 0) { + cache = btrfs_lookup_block_group(fs_info, bytenr); + BUG_ON(!cache); + len = min(num, cache->key.offset - + (bytenr - cache->key.objectid)); + + spin_lock(&cache->space_info->lock); + spin_lock(&cache->lock); + if (reserve) { + cache->reserved += len; + cache->space_info->bytes_reserved += len; + } else { + cache->reserved -= len; + cache->space_info->bytes_reserved -= len; + } + spin_unlock(&cache->lock); + spin_unlock(&cache->space_info->lock); + put_block_group(cache); + bytenr += len; + num -= len; + } + return 0; +} + +int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy) +{ + u64 last = 0; + u64 start; + u64 end; + struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents; + int ret; + + mutex_lock(&root->fs_info->pinned_mutex); + while (1) { + ret = find_first_extent_bit(pinned_extents, last, + &start, &end, EXTENT_DIRTY); + if (ret) + break; + set_extent_dirty(copy, start, end, GFP_NOFS); + last = end + 1; + } + mutex_unlock(&root->fs_info->pinned_mutex); + return 0; +} + +int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_io_tree *unpin) +{ + u64 start; + u64 end; + int ret; + + mutex_lock(&root->fs_info->pinned_mutex); + while (1) { + ret = find_first_extent_bit(unpin, 0, &start, &end, + EXTENT_DIRTY); + if (ret) + break; + + ret = btrfs_discard_extent(root, start, end + 1 - start); + + btrfs_update_pinned_extents(root, start, end + 1 - start, 0); + clear_extent_dirty(unpin, start, end, GFP_NOFS); + + if (need_resched()) { + mutex_unlock(&root->fs_info->pinned_mutex); + cond_resched(); + mutex_lock(&root->fs_info->pinned_mutex); + } + } + mutex_unlock(&root->fs_info->pinned_mutex); + return ret; +} + +static int finish_current_insert(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, int all) +{ + u64 start; + u64 end; + u64 priv; + u64 search = 0; + u64 skipped = 0; + struct btrfs_fs_info *info = extent_root->fs_info; + struct btrfs_path *path; + struct pending_extent_op *extent_op, *tmp; + struct list_head insert_list, update_list; + int ret; + int num_inserts = 0, max_inserts; + + path = btrfs_alloc_path(); + INIT_LIST_HEAD(&insert_list); + INIT_LIST_HEAD(&update_list); + + max_inserts = extent_root->leafsize / + (2 * sizeof(struct btrfs_key) + 2 * sizeof(struct btrfs_item) + + sizeof(struct btrfs_extent_ref) + + sizeof(struct btrfs_extent_item)); +again: + mutex_lock(&info->extent_ins_mutex); + while (1) { + ret = find_first_extent_bit(&info->extent_ins, search, &start, + &end, EXTENT_WRITEBACK); + if (ret) { + if (skipped && all && !num_inserts && + list_empty(&update_list)) { + skipped = 0; + search = 0; + continue; + } + mutex_unlock(&info->extent_ins_mutex); + break; + } + + ret = try_lock_extent(&info->extent_ins, start, end, GFP_NOFS); + if (!ret) { + skipped = 1; + search = end + 1; + if (need_resched()) { + mutex_unlock(&info->extent_ins_mutex); + cond_resched(); + mutex_lock(&info->extent_ins_mutex); + } + continue; + } + + ret = get_state_private(&info->extent_ins, start, &priv); + BUG_ON(ret); + extent_op = (struct pending_extent_op *)(unsigned long) priv; + + if (extent_op->type == PENDING_EXTENT_INSERT) { + num_inserts++; + list_add_tail(&extent_op->list, &insert_list); + search = end + 1; + if (num_inserts == max_inserts) { + mutex_unlock(&info->extent_ins_mutex); + break; + } + } else if (extent_op->type == PENDING_BACKREF_UPDATE) { + list_add_tail(&extent_op->list, &update_list); + search = end + 1; + } else { + BUG(); + } + } + + /* + * process the update list, clear the writeback bit for it, and if + * somebody marked this thing for deletion then just unlock it and be + * done, the free_extents will handle it + */ + mutex_lock(&info->extent_ins_mutex); + list_for_each_entry_safe(extent_op, tmp, &update_list, list) { + clear_extent_bits(&info->extent_ins, extent_op->bytenr, + extent_op->bytenr + extent_op->num_bytes - 1, + EXTENT_WRITEBACK, GFP_NOFS); + if (extent_op->del) { + list_del_init(&extent_op->list); + unlock_extent(&info->extent_ins, extent_op->bytenr, + extent_op->bytenr + extent_op->num_bytes + - 1, GFP_NOFS); + kfree(extent_op); + } + } + mutex_unlock(&info->extent_ins_mutex); + + /* + * still have things left on the update list, go ahead an update + * everything + */ + if (!list_empty(&update_list)) { + ret = update_backrefs(trans, extent_root, path, &update_list); + BUG_ON(ret); + } + + /* + * if no inserts need to be done, but we skipped some extents and we + * need to make sure everything is cleaned then reset everything and + * go back to the beginning + */ + if (!num_inserts && all && skipped) { + search = 0; + skipped = 0; + INIT_LIST_HEAD(&update_list); + INIT_LIST_HEAD(&insert_list); + goto again; + } else if (!num_inserts) { + goto out; + } + + /* + * process the insert extents list. Again if we are deleting this + * extent, then just unlock it, pin down the bytes if need be, and be + * done with it. Saves us from having to actually insert the extent + * into the tree and then subsequently come along and delete it + */ + mutex_lock(&info->extent_ins_mutex); + list_for_each_entry_safe(extent_op, tmp, &insert_list, list) { + clear_extent_bits(&info->extent_ins, extent_op->bytenr, + extent_op->bytenr + extent_op->num_bytes - 1, + EXTENT_WRITEBACK, GFP_NOFS); + if (extent_op->del) { + u64 used; + list_del_init(&extent_op->list); + unlock_extent(&info->extent_ins, extent_op->bytenr, + extent_op->bytenr + extent_op->num_bytes + - 1, GFP_NOFS); + + mutex_lock(&extent_root->fs_info->pinned_mutex); + ret = pin_down_bytes(trans, extent_root, + extent_op->bytenr, + extent_op->num_bytes, 0); + mutex_unlock(&extent_root->fs_info->pinned_mutex); + + spin_lock(&info->delalloc_lock); + used = btrfs_super_bytes_used(&info->super_copy); + btrfs_set_super_bytes_used(&info->super_copy, + used - extent_op->num_bytes); + used = btrfs_root_used(&extent_root->root_item); + btrfs_set_root_used(&extent_root->root_item, + used - extent_op->num_bytes); + spin_unlock(&info->delalloc_lock); + + ret = update_block_group(trans, extent_root, + extent_op->bytenr, + extent_op->num_bytes, + 0, ret > 0); + BUG_ON(ret); + kfree(extent_op); + num_inserts--; + } + } + mutex_unlock(&info->extent_ins_mutex); + + ret = insert_extents(trans, extent_root, path, &insert_list, + num_inserts); + BUG_ON(ret); + + /* + * if we broke out of the loop in order to insert stuff because we hit + * the maximum number of inserts at a time we can handle, then loop + * back and pick up where we left off + */ + if (num_inserts == max_inserts) { + INIT_LIST_HEAD(&insert_list); + INIT_LIST_HEAD(&update_list); + num_inserts = 0; + goto again; + } + + /* + * again, if we need to make absolutely sure there are no more pending + * extent operations left and we know that we skipped some, go back to + * the beginning and do it all again + */ + if (all && skipped) { + INIT_LIST_HEAD(&insert_list); + INIT_LIST_HEAD(&update_list); + search = 0; + skipped = 0; + num_inserts = 0; + goto again; + } +out: + btrfs_free_path(path); + return 0; +} + +static int pin_down_bytes(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, int is_data) +{ + int err = 0; + struct extent_buffer *buf; + + if (is_data) + goto pinit; + + buf = btrfs_find_tree_block(root, bytenr, num_bytes); + if (!buf) + goto pinit; + + /* we can reuse a block if it hasn't been written + * and it is from this transaction. We can't + * reuse anything from the tree log root because + * it has tiny sub-transactions. + */ + if (btrfs_buffer_uptodate(buf, 0) && + btrfs_try_tree_lock(buf)) { + u64 header_owner = btrfs_header_owner(buf); + u64 header_transid = btrfs_header_generation(buf); + if (header_owner != BTRFS_TREE_LOG_OBJECTID && + header_owner != BTRFS_TREE_RELOC_OBJECTID && + header_transid == trans->transid && + !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) { + clean_tree_block(NULL, root, buf); + btrfs_tree_unlock(buf); + free_extent_buffer(buf); + return 1; + } + btrfs_tree_unlock(buf); + } + free_extent_buffer(buf); +pinit: + btrfs_update_pinned_extents(root, bytenr, num_bytes, 1); + + BUG_ON(err < 0); + return 0; +} + +/* + * remove an extent from the root, returns 0 on success + */ +static int __free_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, u64 parent, + u64 root_objectid, u64 ref_generation, + u64 owner_objectid, int pin, int mark_free) +{ + struct btrfs_path *path; + struct btrfs_key key; + struct btrfs_fs_info *info = root->fs_info; + struct btrfs_root *extent_root = info->extent_root; + struct extent_buffer *leaf; + int ret; + int extent_slot = 0; + int found_extent = 0; + int num_to_del = 1; + struct btrfs_extent_item *ei; + u32 refs; + + key.objectid = bytenr; + btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); + key.offset = num_bytes; + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + path->reada = 1; + ret = lookup_extent_backref(trans, extent_root, path, + bytenr, parent, root_objectid, + ref_generation, owner_objectid, 1); + if (ret == 0) { + struct btrfs_key found_key; + extent_slot = path->slots[0]; + while (extent_slot > 0) { + extent_slot--; + btrfs_item_key_to_cpu(path->nodes[0], &found_key, + extent_slot); + if (found_key.objectid != bytenr) + break; + if (found_key.type == BTRFS_EXTENT_ITEM_KEY && + found_key.offset == num_bytes) { + found_extent = 1; + break; + } + if (path->slots[0] - extent_slot > 5) + break; + } + if (!found_extent) { + ret = remove_extent_backref(trans, extent_root, path); + BUG_ON(ret); + btrfs_release_path(extent_root, path); + ret = btrfs_search_slot(trans, extent_root, + &key, path, -1, 1); + if (ret) { + printk(KERN_ERR "umm, got %d back from search" + ", was looking for %llu\n", ret, + (unsigned long long)bytenr); + btrfs_print_leaf(extent_root, path->nodes[0]); + } + BUG_ON(ret); + extent_slot = path->slots[0]; + } + } else { + btrfs_print_leaf(extent_root, path->nodes[0]); + WARN_ON(1); + printk(KERN_ERR "btrfs unable to find ref byte nr %llu " + "root %llu gen %llu owner %llu\n", + (unsigned long long)bytenr, + (unsigned long long)root_objectid, + (unsigned long long)ref_generation, + (unsigned long long)owner_objectid); + } + + leaf = path->nodes[0]; + ei = btrfs_item_ptr(leaf, extent_slot, + struct btrfs_extent_item); + refs = btrfs_extent_refs(leaf, ei); + BUG_ON(refs == 0); + refs -= 1; + btrfs_set_extent_refs(leaf, ei, refs); + + btrfs_mark_buffer_dirty(leaf); + + if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) { + struct btrfs_extent_ref *ref; + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_extent_ref); + BUG_ON(btrfs_ref_num_refs(leaf, ref) != 1); + /* if the back ref and the extent are next to each other + * they get deleted below in one shot + */ + path->slots[0] = extent_slot; + num_to_del = 2; + } else if (found_extent) { + /* otherwise delete the extent back ref */ + ret = remove_extent_backref(trans, extent_root, path); + BUG_ON(ret); + /* if refs are 0, we need to setup the path for deletion */ + if (refs == 0) { + btrfs_release_path(extent_root, path); + ret = btrfs_search_slot(trans, extent_root, &key, path, + -1, 1); + BUG_ON(ret); + } + } + + if (refs == 0) { + u64 super_used; + u64 root_used; + + if (pin) { + mutex_lock(&root->fs_info->pinned_mutex); + ret = pin_down_bytes(trans, root, bytenr, num_bytes, + owner_objectid >= BTRFS_FIRST_FREE_OBJECTID); + mutex_unlock(&root->fs_info->pinned_mutex); + if (ret > 0) + mark_free = 1; + BUG_ON(ret < 0); + } + /* block accounting for super block */ + spin_lock(&info->delalloc_lock); + super_used = btrfs_super_bytes_used(&info->super_copy); + btrfs_set_super_bytes_used(&info->super_copy, + super_used - num_bytes); + + /* block accounting for root item */ + root_used = btrfs_root_used(&root->root_item); + btrfs_set_root_used(&root->root_item, + root_used - num_bytes); + spin_unlock(&info->delalloc_lock); + ret = btrfs_del_items(trans, extent_root, path, path->slots[0], + num_to_del); + BUG_ON(ret); + btrfs_release_path(extent_root, path); + + if (owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { + ret = btrfs_del_csums(trans, root, bytenr, num_bytes); + BUG_ON(ret); + } + + ret = update_block_group(trans, root, bytenr, num_bytes, 0, + mark_free); + BUG_ON(ret); + } + btrfs_free_path(path); + finish_current_insert(trans, extent_root, 0); + return ret; +} + +/* + * find all the blocks marked as pending in the radix tree and remove + * them from the extent map + */ +static int del_pending_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, int all) +{ + int ret; + int err = 0; + u64 start; + u64 end; + u64 priv; + u64 search = 0; + int nr = 0, skipped = 0; + struct extent_io_tree *pending_del; + struct extent_io_tree *extent_ins; + struct pending_extent_op *extent_op; + struct btrfs_fs_info *info = extent_root->fs_info; + struct list_head delete_list; + + INIT_LIST_HEAD(&delete_list); + extent_ins = &extent_root->fs_info->extent_ins; + pending_del = &extent_root->fs_info->pending_del; + +again: + mutex_lock(&info->extent_ins_mutex); + while (1) { + ret = find_first_extent_bit(pending_del, search, &start, &end, + EXTENT_WRITEBACK); + if (ret) { + if (all && skipped && !nr) { + search = 0; + skipped = 0; + continue; + } + mutex_unlock(&info->extent_ins_mutex); + break; + } + + ret = try_lock_extent(extent_ins, start, end, GFP_NOFS); + if (!ret) { + search = end+1; + skipped = 1; + + if (need_resched()) { + mutex_unlock(&info->extent_ins_mutex); + cond_resched(); + mutex_lock(&info->extent_ins_mutex); + } + + continue; + } + BUG_ON(ret < 0); + + ret = get_state_private(pending_del, start, &priv); + BUG_ON(ret); + extent_op = (struct pending_extent_op *)(unsigned long)priv; + + clear_extent_bits(pending_del, start, end, EXTENT_WRITEBACK, + GFP_NOFS); + if (!test_range_bit(extent_ins, start, end, + EXTENT_WRITEBACK, 0)) { + list_add_tail(&extent_op->list, &delete_list); + nr++; + } else { + kfree(extent_op); + + ret = get_state_private(&info->extent_ins, start, + &priv); + BUG_ON(ret); + extent_op = (struct pending_extent_op *) + (unsigned long)priv; + + clear_extent_bits(&info->extent_ins, start, end, + EXTENT_WRITEBACK, GFP_NOFS); + + if (extent_op->type == PENDING_BACKREF_UPDATE) { + list_add_tail(&extent_op->list, &delete_list); + search = end + 1; + nr++; + continue; + } + + mutex_lock(&extent_root->fs_info->pinned_mutex); + ret = pin_down_bytes(trans, extent_root, start, + end + 1 - start, 0); + mutex_unlock(&extent_root->fs_info->pinned_mutex); + + ret = update_block_group(trans, extent_root, start, + end + 1 - start, 0, ret > 0); + + unlock_extent(extent_ins, start, end, GFP_NOFS); + BUG_ON(ret); + kfree(extent_op); + } + if (ret) + err = ret; + + search = end + 1; + + if (need_resched()) { + mutex_unlock(&info->extent_ins_mutex); + cond_resched(); + mutex_lock(&info->extent_ins_mutex); + } + } + + if (nr) { + ret = free_extents(trans, extent_root, &delete_list); + BUG_ON(ret); + } + + if (all && skipped) { + INIT_LIST_HEAD(&delete_list); + search = 0; + nr = 0; + goto again; + } + + return err; +} + +/* + * remove an extent from the root, returns 0 on success + */ +static int __btrfs_free_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, u64 parent, + u64 root_objectid, u64 ref_generation, + u64 owner_objectid, int pin) +{ + struct btrfs_root *extent_root = root->fs_info->extent_root; + int pending_ret; + int ret; + + WARN_ON(num_bytes < root->sectorsize); + if (root == extent_root) { + struct pending_extent_op *extent_op = NULL; + + mutex_lock(&root->fs_info->extent_ins_mutex); + if (test_range_bit(&root->fs_info->extent_ins, bytenr, + bytenr + num_bytes - 1, EXTENT_WRITEBACK, 0)) { + u64 priv; + ret = get_state_private(&root->fs_info->extent_ins, + bytenr, &priv); + BUG_ON(ret); + extent_op = (struct pending_extent_op *) + (unsigned long)priv; + + extent_op->del = 1; + if (extent_op->type == PENDING_EXTENT_INSERT) { + mutex_unlock(&root->fs_info->extent_ins_mutex); + return 0; + } + } + + if (extent_op) { + ref_generation = extent_op->orig_generation; + parent = extent_op->orig_parent; + } + + extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); + BUG_ON(!extent_op); + + extent_op->type = PENDING_EXTENT_DELETE; + extent_op->bytenr = bytenr; + extent_op->num_bytes = num_bytes; + extent_op->parent = parent; + extent_op->orig_parent = parent; + extent_op->generation = ref_generation; + extent_op->orig_generation = ref_generation; + extent_op->level = (int)owner_objectid; + INIT_LIST_HEAD(&extent_op->list); + extent_op->del = 0; + + set_extent_bits(&root->fs_info->pending_del, + bytenr, bytenr + num_bytes - 1, + EXTENT_WRITEBACK, GFP_NOFS); + set_state_private(&root->fs_info->pending_del, + bytenr, (unsigned long)extent_op); + mutex_unlock(&root->fs_info->extent_ins_mutex); + return 0; + } + /* if metadata always pin */ + if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) { + if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { + mutex_lock(&root->fs_info->pinned_mutex); + btrfs_update_pinned_extents(root, bytenr, num_bytes, 1); + mutex_unlock(&root->fs_info->pinned_mutex); + update_reserved_extents(root, bytenr, num_bytes, 0); + return 0; + } + pin = 1; + } + + /* if data pin when any transaction has committed this */ + if (ref_generation != trans->transid) + pin = 1; + + ret = __free_extent(trans, root, bytenr, num_bytes, parent, + root_objectid, ref_generation, + owner_objectid, pin, pin == 0); + + finish_current_insert(trans, root->fs_info->extent_root, 0); + pending_ret = del_pending_extents(trans, root->fs_info->extent_root, 0); + return ret ? ret : pending_ret; +} + +int btrfs_free_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u64 num_bytes, u64 parent, + u64 root_objectid, u64 ref_generation, + u64 owner_objectid, int pin) +{ + int ret; + + ret = __btrfs_free_extent(trans, root, bytenr, num_bytes, parent, + root_objectid, ref_generation, + owner_objectid, pin); + return ret; +} + +static u64 stripe_align(struct btrfs_root *root, u64 val) +{ + u64 mask = ((u64)root->stripesize - 1); + u64 ret = (val + mask) & ~mask; + return ret; +} + +/* + * walks the btree of allocated extents and find a hole of a given size. + * The key ins is changed to record the hole: + * ins->objectid == block start + * ins->flags = BTRFS_EXTENT_ITEM_KEY + * ins->offset == number of blocks + * Any available blocks before search_start are skipped. + */ +static noinline int find_free_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *orig_root, + u64 num_bytes, u64 empty_size, + u64 search_start, u64 search_end, + u64 hint_byte, struct btrfs_key *ins, + u64 exclude_start, u64 exclude_nr, + int data) +{ + int ret = 0; + struct btrfs_root *root = orig_root->fs_info->extent_root; + u64 total_needed = num_bytes; + u64 *last_ptr = NULL; + u64 last_wanted = 0; + struct btrfs_block_group_cache *block_group = NULL; + int chunk_alloc_done = 0; + int empty_cluster = 2 * 1024 * 1024; + int allowed_chunk_alloc = 0; + struct list_head *head = NULL, *cur = NULL; + int loop = 0; + int extra_loop = 0; + struct btrfs_space_info *space_info; + + WARN_ON(num_bytes < root->sectorsize); + btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); + ins->objectid = 0; + ins->offset = 0; + + if (orig_root->ref_cows || empty_size) + allowed_chunk_alloc = 1; + + if (data & BTRFS_BLOCK_GROUP_METADATA) { + last_ptr = &root->fs_info->last_alloc; + empty_cluster = 64 * 1024; + } + + if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) + last_ptr = &root->fs_info->last_data_alloc; + + if (last_ptr) { + if (*last_ptr) { + hint_byte = *last_ptr; + last_wanted = *last_ptr; + } else + empty_size += empty_cluster; + } else { + empty_cluster = 0; + } + search_start = max(search_start, first_logical_byte(root, 0)); + search_start = max(search_start, hint_byte); + + if (last_wanted && search_start != last_wanted) { + last_wanted = 0; + empty_size += empty_cluster; + } + + total_needed += empty_size; + block_group = btrfs_lookup_block_group(root->fs_info, search_start); + if (!block_group) + block_group = btrfs_lookup_first_block_group(root->fs_info, + search_start); + space_info = __find_space_info(root->fs_info, data); + + down_read(&space_info->groups_sem); + while (1) { + struct btrfs_free_space *free_space; + /* + * the only way this happens if our hint points to a block + * group thats not of the proper type, while looping this + * should never happen + */ + if (empty_size) + extra_loop = 1; + + if (!block_group) + goto new_group_no_lock; + + if (unlikely(!block_group->cached)) { + mutex_lock(&block_group->cache_mutex); + ret = cache_block_group(root, block_group); + mutex_unlock(&block_group->cache_mutex); + if (ret) + break; + } + + mutex_lock(&block_group->alloc_mutex); + if (unlikely(!block_group_bits(block_group, data))) + goto new_group; + + if (unlikely(block_group->ro)) + goto new_group; + + free_space = btrfs_find_free_space(block_group, search_start, + total_needed); + if (free_space) { + u64 start = block_group->key.objectid; + u64 end = block_group->key.objectid + + block_group->key.offset; + + search_start = stripe_align(root, free_space->offset); + + /* move on to the next group */ + if (search_start + num_bytes >= search_end) + goto new_group; + + /* move on to the next group */ + if (search_start + num_bytes > end) + goto new_group; + + if (last_wanted && search_start != last_wanted) { + total_needed += empty_cluster; + empty_size += empty_cluster; + last_wanted = 0; + /* + * if search_start is still in this block group + * then we just re-search this block group + */ + if (search_start >= start && + search_start < end) { + mutex_unlock(&block_group->alloc_mutex); + continue; + } + + /* else we go to the next block group */ + goto new_group; + } + + if (exclude_nr > 0 && + (search_start + num_bytes > exclude_start && + search_start < exclude_start + exclude_nr)) { + search_start = exclude_start + exclude_nr; + /* + * if search_start is still in this block group + * then we just re-search this block group + */ + if (search_start >= start && + search_start < end) { + mutex_unlock(&block_group->alloc_mutex); + last_wanted = 0; + continue; + } + + /* else we go to the next block group */ + goto new_group; + } + + ins->objectid = search_start; + ins->offset = num_bytes; + + btrfs_remove_free_space_lock(block_group, search_start, + num_bytes); + /* we are all good, lets return */ + mutex_unlock(&block_group->alloc_mutex); + break; + } +new_group: + mutex_unlock(&block_group->alloc_mutex); + put_block_group(block_group); + block_group = NULL; +new_group_no_lock: + /* don't try to compare new allocations against the + * last allocation any more + */ + last_wanted = 0; + + /* + * Here's how this works. + * loop == 0: we were searching a block group via a hint + * and didn't find anything, so we start at + * the head of the block groups and keep searching + * loop == 1: we're searching through all of the block groups + * if we hit the head again we have searched + * all of the block groups for this space and we + * need to try and allocate, if we cant error out. + * loop == 2: we allocated more space and are looping through + * all of the block groups again. + */ + if (loop == 0) { + head = &space_info->block_groups; + cur = head->next; + loop++; + } else if (loop == 1 && cur == head) { + int keep_going; + + /* at this point we give up on the empty_size + * allocations and just try to allocate the min + * space. + * + * The extra_loop field was set if an empty_size + * allocation was attempted above, and if this + * is try we need to try the loop again without + * the additional empty_size. + */ + total_needed -= empty_size; + empty_size = 0; + keep_going = extra_loop; + loop++; + + if (allowed_chunk_alloc && !chunk_alloc_done) { + up_read(&space_info->groups_sem); + ret = do_chunk_alloc(trans, root, num_bytes + + 2 * 1024 * 1024, data, 1); + down_read(&space_info->groups_sem); + if (ret < 0) + goto loop_check; + head = &space_info->block_groups; + /* + * we've allocated a new chunk, keep + * trying + */ + keep_going = 1; + chunk_alloc_done = 1; + } else if (!allowed_chunk_alloc) { + space_info->force_alloc = 1; + } +loop_check: + if (keep_going) { + cur = head->next; + extra_loop = 0; + } else { + break; + } + } else if (cur == head) { + break; + } + + block_group = list_entry(cur, struct btrfs_block_group_cache, + list); + atomic_inc(&block_group->count); + + search_start = block_group->key.objectid; + cur = cur->next; + } + + /* we found what we needed */ + if (ins->objectid) { + if (!(data & BTRFS_BLOCK_GROUP_DATA)) + trans->block_group = block_group->key.objectid; + + if (last_ptr) + *last_ptr = ins->objectid + ins->offset; + ret = 0; + } else if (!ret) { + printk(KERN_ERR "btrfs searching for %llu bytes, " + "num_bytes %llu, loop %d, allowed_alloc %d\n", + (unsigned long long)total_needed, + (unsigned long long)num_bytes, + loop, allowed_chunk_alloc); + ret = -ENOSPC; + } + if (block_group) + put_block_group(block_group); + + up_read(&space_info->groups_sem); + return ret; +} + +static void dump_space_info(struct btrfs_space_info *info, u64 bytes) +{ + struct btrfs_block_group_cache *cache; + + printk(KERN_INFO "space_info has %llu free, is %sfull\n", + (unsigned long long)(info->total_bytes - info->bytes_used - + info->bytes_pinned - info->bytes_reserved), + (info->full) ? "" : "not "); + + down_read(&info->groups_sem); + list_for_each_entry(cache, &info->block_groups, list) { + spin_lock(&cache->lock); + printk(KERN_INFO "block group %llu has %llu bytes, %llu used " + "%llu pinned %llu reserved\n", + (unsigned long long)cache->key.objectid, + (unsigned long long)cache->key.offset, + (unsigned long long)btrfs_block_group_used(&cache->item), + (unsigned long long)cache->pinned, + (unsigned long long)cache->reserved); + btrfs_dump_free_space(cache, bytes); + spin_unlock(&cache->lock); + } + up_read(&info->groups_sem); +} + +static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 num_bytes, u64 min_alloc_size, + u64 empty_size, u64 hint_byte, + u64 search_end, struct btrfs_key *ins, + u64 data) +{ + int ret; + u64 search_start = 0; + u64 alloc_profile; + struct btrfs_fs_info *info = root->fs_info; + + if (data) { + alloc_profile = info->avail_data_alloc_bits & + info->data_alloc_profile; + data = BTRFS_BLOCK_GROUP_DATA | alloc_profile; + } else if (root == root->fs_info->chunk_root) { + alloc_profile = info->avail_system_alloc_bits & + info->system_alloc_profile; + data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile; + } else { + alloc_profile = info->avail_metadata_alloc_bits & + info->metadata_alloc_profile; + data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile; + } +again: + data = btrfs_reduce_alloc_profile(root, data); + /* + * the only place that sets empty_size is btrfs_realloc_node, which + * is not called recursively on allocations + */ + if (empty_size || root->ref_cows) { + if (!(data & BTRFS_BLOCK_GROUP_METADATA)) { + ret = do_chunk_alloc(trans, root->fs_info->extent_root, + 2 * 1024 * 1024, + BTRFS_BLOCK_GROUP_METADATA | + (info->metadata_alloc_profile & + info->avail_metadata_alloc_bits), 0); + } + ret = do_chunk_alloc(trans, root->fs_info->extent_root, + num_bytes + 2 * 1024 * 1024, data, 0); + } + + WARN_ON(num_bytes < root->sectorsize); + ret = find_free_extent(trans, root, num_bytes, empty_size, + search_start, search_end, hint_byte, ins, + trans->alloc_exclude_start, + trans->alloc_exclude_nr, data); + + if (ret == -ENOSPC && num_bytes > min_alloc_size) { + num_bytes = num_bytes >> 1; + num_bytes = num_bytes & ~(root->sectorsize - 1); + num_bytes = max(num_bytes, min_alloc_size); + do_chunk_alloc(trans, root->fs_info->extent_root, + num_bytes, data, 1); + goto again; + } + if (ret) { + struct btrfs_space_info *sinfo; + + sinfo = __find_space_info(root->fs_info, data); + printk(KERN_ERR "btrfs allocation failed flags %llu, " + "wanted %llu\n", (unsigned long long)data, + (unsigned long long)num_bytes); + dump_space_info(sinfo, num_bytes); + BUG(); + } + + return ret; +} + +int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len) +{ + struct btrfs_block_group_cache *cache; + int ret = 0; + + cache = btrfs_lookup_block_group(root->fs_info, start); + if (!cache) { + printk(KERN_ERR "Unable to find block group for %llu\n", + (unsigned long long)start); + return -ENOSPC; } - return NULL; + ret = btrfs_discard_extent(root, start, len); + + btrfs_add_free_space(cache, start, len); + put_block_group(cache); + update_reserved_extents(root, start, len, 0); + + return ret; } -static int update_space_info(struct btrfs_fs_info *info, u64 flags, - u64 total_bytes, u64 bytes_used, - struct btrfs_space_info **space_info) +int btrfs_reserve_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 num_bytes, u64 min_alloc_size, + u64 empty_size, u64 hint_byte, + u64 search_end, struct btrfs_key *ins, + u64 data) { - struct btrfs_space_info *found; + int ret; + ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size, + empty_size, hint_byte, search_end, ins, + data); + update_reserved_extents(root, ins->objectid, ins->offset, 1); + return ret; +} - found = __find_space_info(info, flags); - if (found) { - found->total_bytes += total_bytes; - found->bytes_used += bytes_used; - found->full = 0; - *space_info = found; - return 0; +static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 parent, + u64 root_objectid, u64 ref_generation, + u64 owner, struct btrfs_key *ins) +{ + int ret; + int pending_ret; + u64 super_used; + u64 root_used; + u64 num_bytes = ins->offset; + u32 sizes[2]; + struct btrfs_fs_info *info = root->fs_info; + struct btrfs_root *extent_root = info->extent_root; + struct btrfs_extent_item *extent_item; + struct btrfs_extent_ref *ref; + struct btrfs_path *path; + struct btrfs_key keys[2]; + + if (parent == 0) + parent = ins->objectid; + + /* block accounting for super block */ + spin_lock(&info->delalloc_lock); + super_used = btrfs_super_bytes_used(&info->super_copy); + btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes); + + /* block accounting for root item */ + root_used = btrfs_root_used(&root->root_item); + btrfs_set_root_used(&root->root_item, root_used + num_bytes); + spin_unlock(&info->delalloc_lock); + + if (root == extent_root) { + struct pending_extent_op *extent_op; + + extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS); + BUG_ON(!extent_op); + + extent_op->type = PENDING_EXTENT_INSERT; + extent_op->bytenr = ins->objectid; + extent_op->num_bytes = ins->offset; + extent_op->parent = parent; + extent_op->orig_parent = 0; + extent_op->generation = ref_generation; + extent_op->orig_generation = 0; + extent_op->level = (int)owner; + INIT_LIST_HEAD(&extent_op->list); + extent_op->del = 0; + + mutex_lock(&root->fs_info->extent_ins_mutex); + set_extent_bits(&root->fs_info->extent_ins, ins->objectid, + ins->objectid + ins->offset - 1, + EXTENT_WRITEBACK, GFP_NOFS); + set_state_private(&root->fs_info->extent_ins, + ins->objectid, (unsigned long)extent_op); + mutex_unlock(&root->fs_info->extent_ins_mutex); + goto update_block; } - found = kmalloc(sizeof(*found), GFP_NOFS); - if (!found) - return -ENOMEM; - list_add(&found->list, &info->space_info); - found->flags = flags; - found->total_bytes = total_bytes; - found->bytes_used = bytes_used; - found->bytes_pinned = 0; - found->full = 0; - found->force_alloc = 0; - *space_info = found; - return 0; + memcpy(&keys[0], ins, sizeof(*ins)); + keys[1].objectid = ins->objectid; + keys[1].type = BTRFS_EXTENT_REF_KEY; + keys[1].offset = parent; + sizes[0] = sizeof(*extent_item); + sizes[1] = sizeof(*ref); + + path = btrfs_alloc_path(); + BUG_ON(!path); + + ret = btrfs_insert_empty_items(trans, extent_root, path, keys, + sizes, 2); + BUG_ON(ret); + + extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_extent_item); + btrfs_set_extent_refs(path->nodes[0], extent_item, 1); + ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, + struct btrfs_extent_ref); + + btrfs_set_ref_root(path->nodes[0], ref, root_objectid); + btrfs_set_ref_generation(path->nodes[0], ref, ref_generation); + btrfs_set_ref_objectid(path->nodes[0], ref, owner); + btrfs_set_ref_num_refs(path->nodes[0], ref, 1); + + btrfs_mark_buffer_dirty(path->nodes[0]); + + trans->alloc_exclude_start = 0; + trans->alloc_exclude_nr = 0; + btrfs_free_path(path); + finish_current_insert(trans, extent_root, 0); + pending_ret = del_pending_extents(trans, extent_root, 0); + + if (ret) + goto out; + if (pending_ret) { + ret = pending_ret; + goto out; + } + +update_block: + ret = update_block_group(trans, root, ins->objectid, + ins->offset, 1, 0); + if (ret) { + printk(KERN_ERR "btrfs update block group failed for %llu " + "%llu\n", (unsigned long long)ins->objectid, + (unsigned long long)ins->offset); + BUG(); + } +out: + return ret; } -static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) +int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 parent, + u64 root_objectid, u64 ref_generation, + u64 owner, struct btrfs_key *ins) { - u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 | - BTRFS_BLOCK_GROUP_RAID1 | - BTRFS_BLOCK_GROUP_RAID10 | - BTRFS_BLOCK_GROUP_DUP); - if (extra_flags) { - if (flags & BTRFS_BLOCK_GROUP_DATA) - fs_info->avail_data_alloc_bits |= extra_flags; - if (flags & BTRFS_BLOCK_GROUP_METADATA) - fs_info->avail_metadata_alloc_bits |= extra_flags; - if (flags & BTRFS_BLOCK_GROUP_SYSTEM) - fs_info->avail_system_alloc_bits |= extra_flags; + int ret; + + if (root_objectid == BTRFS_TREE_LOG_OBJECTID) + return 0; + ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid, + ref_generation, owner, ins); + update_reserved_extents(root, ins->objectid, ins->offset, 0); + return ret; +} + +/* + * this is used by the tree logging recovery code. It records that + * an extent has been allocated and makes sure to clear the free + * space cache bits as well + */ +int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 parent, + u64 root_objectid, u64 ref_generation, + u64 owner, struct btrfs_key *ins) +{ + int ret; + struct btrfs_block_group_cache *block_group; + + block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid); + mutex_lock(&block_group->cache_mutex); + cache_block_group(root, block_group); + mutex_unlock(&block_group->cache_mutex); + + ret = btrfs_remove_free_space(block_group, ins->objectid, + ins->offset); + BUG_ON(ret); + put_block_group(block_group); + ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid, + ref_generation, owner, ins); + return ret; +} + +/* + * finds a free extent and does all the dirty work required for allocation + * returns the key for the extent through ins, and a tree buffer for + * the first block of the extent through buf. + * + * returns 0 if everything worked, non-zero otherwise. + */ +int btrfs_alloc_extent(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 num_bytes, u64 parent, u64 min_alloc_size, + u64 root_objectid, u64 ref_generation, + u64 owner_objectid, u64 empty_size, u64 hint_byte, + u64 search_end, struct btrfs_key *ins, u64 data) +{ + int ret; + + ret = __btrfs_reserve_extent(trans, root, num_bytes, + min_alloc_size, empty_size, hint_byte, + search_end, ins, data); + BUG_ON(ret); + if (root_objectid != BTRFS_TREE_LOG_OBJECTID) { + ret = __btrfs_alloc_reserved_extent(trans, root, parent, + root_objectid, ref_generation, + owner_objectid, ins); + BUG_ON(ret); + + } else { + update_reserved_extents(root, ins->objectid, ins->offset, 1); } + return ret; } -static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags) +struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 bytenr, u32 blocksize) { - u64 num_devices = root->fs_info->fs_devices->num_devices; + struct extent_buffer *buf; - if (num_devices == 1) - flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0); - if (num_devices < 4) - flags &= ~BTRFS_BLOCK_GROUP_RAID10; + buf = btrfs_find_create_tree_block(root, bytenr, blocksize); + if (!buf) + return ERR_PTR(-ENOMEM); + btrfs_set_header_generation(buf, trans->transid); + btrfs_tree_lock(buf); + clean_tree_block(trans, root, buf); - if ((flags & BTRFS_BLOCK_GROUP_DUP) && - (flags & (BTRFS_BLOCK_GROUP_RAID1 | - BTRFS_BLOCK_GROUP_RAID10))) { - flags &= ~BTRFS_BLOCK_GROUP_DUP; + btrfs_set_lock_blocking(buf); + btrfs_set_buffer_uptodate(buf); + + if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { + set_extent_dirty(&root->dirty_log_pages, buf->start, + buf->start + buf->len - 1, GFP_NOFS); + } else { + set_extent_dirty(&trans->transaction->dirty_pages, buf->start, + buf->start + buf->len - 1, GFP_NOFS); + } + trans->blocks_used++; + /* this returns a buffer locked for blocking */ + return buf; +} + +/* + * helper function to allocate a block for a given tree + * returns the tree buffer or NULL. + */ +struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u32 blocksize, u64 parent, + u64 root_objectid, + u64 ref_generation, + int level, + u64 hint, + u64 empty_size) +{ + struct btrfs_key ins; + int ret; + struct extent_buffer *buf; + + ret = btrfs_alloc_extent(trans, root, blocksize, parent, blocksize, + root_objectid, ref_generation, level, + empty_size, hint, (u64)-1, &ins, 0); + if (ret) { + BUG_ON(ret > 0); + return ERR_PTR(ret); } - if ((flags & BTRFS_BLOCK_GROUP_RAID1) && - (flags & BTRFS_BLOCK_GROUP_RAID10)) { - flags &= ~BTRFS_BLOCK_GROUP_RAID1; - } + buf = btrfs_init_new_buffer(trans, root, ins.objectid, blocksize); + return buf; +} + +int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct extent_buffer *leaf) +{ + u64 leaf_owner; + u64 leaf_generation; + struct refsort *sorted; + struct btrfs_key key; + struct btrfs_file_extent_item *fi; + int i; + int nritems; + int ret; + int refi = 0; + int slot; + + BUG_ON(!btrfs_is_leaf(leaf)); + nritems = btrfs_header_nritems(leaf); + leaf_owner = btrfs_header_owner(leaf); + leaf_generation = btrfs_header_generation(leaf); + + sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS); + /* we do this loop twice. The first time we build a list + * of the extents we have a reference on, then we sort the list + * by bytenr. The second time around we actually do the + * extent freeing. + */ + for (i = 0; i < nritems; i++) { + u64 disk_bytenr; + cond_resched(); + + btrfs_item_key_to_cpu(leaf, &key, i); + + /* only extents have references, skip everything else */ + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + continue; + + fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); - if ((flags & BTRFS_BLOCK_GROUP_RAID0) && - ((flags & BTRFS_BLOCK_GROUP_RAID1) | - (flags & BTRFS_BLOCK_GROUP_RAID10) | - (flags & BTRFS_BLOCK_GROUP_DUP))) - flags &= ~BTRFS_BLOCK_GROUP_RAID0; - return flags; -} + /* inline extents live in the btree, they don't have refs */ + if (btrfs_file_extent_type(leaf, fi) == + BTRFS_FILE_EXTENT_INLINE) + continue; -static int do_chunk_alloc(struct btrfs_trans_handle *trans, - struct btrfs_root *extent_root, u64 alloc_bytes, - u64 flags, int force) -{ - struct btrfs_space_info *space_info; - u64 thresh; - u64 start; - u64 num_bytes; - int ret; + disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); - flags = reduce_alloc_profile(extent_root, flags); + /* holes don't have refs */ + if (disk_bytenr == 0) + continue; - space_info = __find_space_info(extent_root->fs_info, flags); - if (!space_info) { - ret = update_space_info(extent_root->fs_info, flags, - 0, 0, &space_info); - BUG_ON(ret); + sorted[refi].bytenr = disk_bytenr; + sorted[refi].slot = i; + refi++; } - BUG_ON(!space_info); - if (space_info->force_alloc) { - force = 1; - space_info->force_alloc = 0; - } - if (space_info->full) + if (refi == 0) goto out; - thresh = div_factor(space_info->total_bytes, 6); - if (!force && - (space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) < - thresh) - goto out; + sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL); - mutex_lock(&extent_root->fs_info->chunk_mutex); - ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags); - if (ret == -ENOSPC) { -printk("space info full %Lu\n", flags); - space_info->full = 1; - goto out_unlock; - } - BUG_ON(ret); + for (i = 0; i < refi; i++) { + u64 disk_bytenr; - ret = btrfs_make_block_group(trans, extent_root, 0, flags, - BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes); - BUG_ON(ret); -out_unlock: - mutex_unlock(&extent_root->fs_info->chunk_mutex); + disk_bytenr = sorted[i].bytenr; + slot = sorted[i].slot; + + cond_resched(); + + btrfs_item_key_to_cpu(leaf, &key, slot); + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + continue; + + fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); + + ret = __btrfs_free_extent(trans, root, disk_bytenr, + btrfs_file_extent_disk_num_bytes(leaf, fi), + leaf->start, leaf_owner, leaf_generation, + key.objectid, 0); + BUG_ON(ret); + + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); + } out: + kfree(sorted); return 0; } -static int update_block_group(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 bytenr, u64 num_bytes, int alloc, - int mark_free) +static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_leaf_ref *ref) { - struct btrfs_block_group_cache *cache; - struct btrfs_fs_info *info = root->fs_info; - u64 total = num_bytes; - u64 old_val; - u64 byte_in_group; - u64 start; - u64 end; + int i; + int ret; + struct btrfs_extent_info *info; + struct refsort *sorted; - WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex)); - while(total) { - cache = btrfs_lookup_block_group(info, bytenr); - if (!cache) { - return -1; - } - byte_in_group = bytenr - cache->key.objectid; - WARN_ON(byte_in_group > cache->key.offset); - start = cache->key.objectid; - end = start + cache->key.offset - 1; - set_extent_bits(&info->block_group_cache, start, end, - BLOCK_GROUP_DIRTY, GFP_NOFS); + if (ref->nritems == 0) + return 0; - spin_lock(&cache->lock); - old_val = btrfs_block_group_used(&cache->item); - num_bytes = min(total, cache->key.offset - byte_in_group); - if (alloc) { - old_val += num_bytes; - cache->space_info->bytes_used += num_bytes; - btrfs_set_block_group_used(&cache->item, old_val); - spin_unlock(&cache->lock); - } else { - old_val -= num_bytes; - cache->space_info->bytes_used -= num_bytes; - btrfs_set_block_group_used(&cache->item, old_val); - spin_unlock(&cache->lock); - if (mark_free) { - set_extent_dirty(&info->free_space_cache, - bytenr, bytenr + num_bytes - 1, - GFP_NOFS); - } - } - total -= num_bytes; - bytenr += num_bytes; + sorted = kmalloc(sizeof(*sorted) * ref->nritems, GFP_NOFS); + for (i = 0; i < ref->nritems; i++) { + sorted[i].bytenr = ref->extents[i].bytenr; + sorted[i].slot = i; + } + sort(sorted, ref->nritems, sizeof(struct refsort), refsort_cmp, NULL); + + /* + * the items in the ref were sorted when the ref was inserted + * into the ref cache, so this is already in order + */ + for (i = 0; i < ref->nritems; i++) { + info = ref->extents + sorted[i].slot; + ret = __btrfs_free_extent(trans, root, info->bytenr, + info->num_bytes, ref->bytenr, + ref->owner, ref->generation, + info->objectid, 0); + + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); + + BUG_ON(ret); + info++; } + + kfree(sorted); return 0; } -static u64 first_logical_byte(struct btrfs_root *root, u64 search_start) +static int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, + u64 len, u32 *refs) { - u64 start; - u64 end; int ret; - ret = find_first_extent_bit(&root->fs_info->block_group_cache, - search_start, &start, &end, - BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA | - BLOCK_GROUP_SYSTEM); - if (ret) - return 0; - return start; -} + ret = btrfs_lookup_extent_ref(NULL, root, start, len, refs); + BUG_ON(ret); -int btrfs_update_pinned_extents(struct btrfs_root *root, - u64 bytenr, u64 num, int pin) -{ - u64 len; - struct btrfs_block_group_cache *cache; - struct btrfs_fs_info *fs_info = root->fs_info; +#if 0 /* some debugging code in case we see problems here */ + /* if the refs count is one, it won't get increased again. But + * if the ref count is > 1, someone may be decreasing it at + * the same time we are. + */ + if (*refs != 1) { + struct extent_buffer *eb = NULL; + eb = btrfs_find_create_tree_block(root, start, len); + if (eb) + btrfs_tree_lock(eb); - WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex)); - if (pin) { - set_extent_dirty(&fs_info->pinned_extents, - bytenr, bytenr + num - 1, GFP_NOFS); - } else { - clear_extent_dirty(&fs_info->pinned_extents, - bytenr, bytenr + num - 1, GFP_NOFS); - } - while (num > 0) { - cache = btrfs_lookup_block_group(fs_info, bytenr); - if (!cache) { - u64 first = first_logical_byte(root, bytenr); - WARN_ON(first < bytenr); - len = min(first - bytenr, num); - } else { - len = min(num, cache->key.offset - - (bytenr - cache->key.objectid)); + mutex_lock(&root->fs_info->alloc_mutex); + ret = lookup_extent_ref(NULL, root, start, len, refs); + BUG_ON(ret); + mutex_unlock(&root->fs_info->alloc_mutex); + + if (eb) { + btrfs_tree_unlock(eb); + free_extent_buffer(eb); } - if (pin) { - if (cache) { - spin_lock(&cache->lock); - cache->pinned += len; - cache->space_info->bytes_pinned += len; - spin_unlock(&cache->lock); - } - fs_info->total_pinned += len; - } else { - if (cache) { - spin_lock(&cache->lock); - cache->pinned -= len; - cache->space_info->bytes_pinned -= len; - spin_unlock(&cache->lock); - } - fs_info->total_pinned -= len; + if (*refs == 1) { + printk(KERN_ERR "btrfs block %llu went down to one " + "during drop_snap\n", (unsigned long long)start); } - bytenr += len; - num -= len; + } - return 0; +#endif + + cond_resched(); + return ret; } -int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy) +/* + * this is used while deleting old snapshots, and it drops the refs + * on a whole subtree starting from a level 1 node. + * + * The idea is to sort all the leaf pointers, and then drop the + * ref on all the leaves in order. Most of the time the leaves + * will have ref cache entries, so no leaf IOs will be required to + * find the extents they have references on. + * + * For each leaf, any references it has are also dropped in order + * + * This ends up dropping the references in something close to optimal + * order for reading and modifying the extent allocation tree. + */ +static noinline int drop_level_one_refs(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path) { - u64 last = 0; - u64 start; - u64 end; - struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents; + u64 bytenr; + u64 root_owner; + u64 root_gen; + struct extent_buffer *eb = path->nodes[1]; + struct extent_buffer *leaf; + struct btrfs_leaf_ref *ref; + struct refsort *sorted = NULL; + int nritems = btrfs_header_nritems(eb); int ret; + int i; + int refi = 0; + int slot = path->slots[1]; + u32 blocksize = btrfs_level_size(root, 0); + u32 refs; - while(1) { - ret = find_first_extent_bit(pinned_extents, last, - &start, &end, EXTENT_DIRTY); - if (ret) - break; - set_extent_dirty(copy, start, end, GFP_NOFS); - last = end + 1; + if (nritems == 0) + goto out; + + root_owner = btrfs_header_owner(eb); + root_gen = btrfs_header_generation(eb); + sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS); + + /* + * step one, sort all the leaf pointers so we don't scribble + * randomly into the extent allocation tree + */ + for (i = slot; i < nritems; i++) { + sorted[refi].bytenr = btrfs_node_blockptr(eb, i); + sorted[refi].slot = i; + refi++; } - return 0; -} -int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct extent_io_tree *unpin) -{ - u64 start; - u64 end; - int ret; - struct extent_io_tree *free_space_cache; - free_space_cache = &root->fs_info->free_space_cache; + /* + * nritems won't be zero, but if we're picking up drop_snapshot + * after a crash, slot might be > 0, so double check things + * just in case. + */ + if (refi == 0) + goto out; - mutex_lock(&root->fs_info->alloc_mutex); - while(1) { - ret = find_first_extent_bit(unpin, 0, &start, &end, - EXTENT_DIRTY); - if (ret) - break; - btrfs_update_pinned_extents(root, start, end + 1 - start, 0); - clear_extent_dirty(unpin, start, end, GFP_NOFS); - set_extent_dirty(free_space_cache, start, end, GFP_NOFS); - if (need_resched()) { - mutex_unlock(&root->fs_info->alloc_mutex); - cond_resched(); - mutex_lock(&root->fs_info->alloc_mutex); + sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL); + + /* + * the first loop frees everything the leaves point to + */ + for (i = 0; i < refi; i++) { + u64 ptr_gen; + + bytenr = sorted[i].bytenr; + + /* + * check the reference count on this leaf. If it is > 1 + * we just decrement it below and don't update any + * of the refs the leaf points to. + */ + ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs); + BUG_ON(ret); + if (refs != 1) + continue; + + ptr_gen = btrfs_node_ptr_generation(eb, sorted[i].slot); + + /* + * the leaf only had one reference, which means the + * only thing pointing to this leaf is the snapshot + * we're deleting. It isn't possible for the reference + * count to increase again later + * + * The reference cache is checked for the leaf, + * and if found we'll be able to drop any refs held by + * the leaf without needing to read it in. + */ + ref = btrfs_lookup_leaf_ref(root, bytenr); + if (ref && ref->generation != ptr_gen) { + btrfs_free_leaf_ref(root, ref); + ref = NULL; + } + if (ref) { + ret = cache_drop_leaf_ref(trans, root, ref); + BUG_ON(ret); + btrfs_remove_leaf_ref(root, ref); + btrfs_free_leaf_ref(root, ref); + } else { + /* + * the leaf wasn't in the reference cache, so + * we have to read it. + */ + leaf = read_tree_block(root, bytenr, blocksize, + ptr_gen); + ret = btrfs_drop_leaf_ref(trans, root, leaf); + BUG_ON(ret); + free_extent_buffer(leaf); } + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); + } + + /* + * run through the loop again to free the refs on the leaves. + * This is faster than doing it in the loop above because + * the leaves are likely to be clustered together. We end up + * working in nice chunks on the extent allocation tree. + */ + for (i = 0; i < refi; i++) { + bytenr = sorted[i].bytenr; + ret = __btrfs_free_extent(trans, root, bytenr, + blocksize, eb->start, + root_owner, root_gen, 0, 1); + BUG_ON(ret); + + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); } - mutex_unlock(&root->fs_info->alloc_mutex); +out: + kfree(sorted); + + /* + * update the path to show we've processed the entire level 1 + * node. This will get saved into the root's drop_snapshot_progress + * field so these drops are not repeated again if this transaction + * commits. + */ + path->slots[1] = nritems; return 0; } -static int finish_current_insert(struct btrfs_trans_handle *trans, - struct btrfs_root *extent_root) +/* + * helper function for drop_snapshot, this walks down the tree dropping ref + * counts as it goes. + */ +static noinline int walk_down_tree(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, int *level) { - u64 start; - u64 end; - struct btrfs_fs_info *info = extent_root->fs_info; - struct extent_buffer *eb; - struct btrfs_path *path; - struct btrfs_key ins; - struct btrfs_disk_key first; - struct btrfs_extent_item extent_item; + u64 root_owner; + u64 root_gen; + u64 bytenr; + u64 ptr_gen; + struct extent_buffer *next; + struct extent_buffer *cur; + struct extent_buffer *parent; + u32 blocksize; int ret; - int level; - int err = 0; - - WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex)); - btrfs_set_stack_extent_refs(&extent_item, 1); - btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY); - path = btrfs_alloc_path(); + u32 refs; - while(1) { - ret = find_first_extent_bit(&info->extent_ins, 0, &start, - &end, EXTENT_LOCKED); - if (ret) - break; + WARN_ON(*level < 0); + WARN_ON(*level >= BTRFS_MAX_LEVEL); + ret = drop_snap_lookup_refcount(root, path->nodes[*level]->start, + path->nodes[*level]->len, &refs); + BUG_ON(ret); + if (refs > 1) + goto out; - ins.objectid = start; - ins.offset = end + 1 - start; - err = btrfs_insert_item(trans, extent_root, &ins, - &extent_item, sizeof(extent_item)); - clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED, - GFP_NOFS); + /* + * walk down to the last node level and free all the leaves + */ + while (*level >= 0) { + WARN_ON(*level < 0); + WARN_ON(*level >= BTRFS_MAX_LEVEL); + cur = path->nodes[*level]; - eb = btrfs_find_create_tree_block(extent_root, ins.objectid, - ins.offset); + if (btrfs_header_level(cur) != *level) + WARN_ON(1); - if (!btrfs_buffer_uptodate(eb, trans->transid)) - btrfs_read_buffer(eb, trans->transid); + if (path->slots[*level] >= + btrfs_header_nritems(cur)) + break; - btrfs_tree_lock(eb); - level = btrfs_header_level(eb); - if (level == 0) { - btrfs_item_key(eb, &first, 0); - } else { - btrfs_node_key(eb, &first, 0); + /* the new code goes down to level 1 and does all the + * leaves pointed to that node in bulk. So, this check + * for level 0 will always be false. + * + * But, the disk format allows the drop_snapshot_progress + * field in the root to leave things in a state where + * a leaf will need cleaning up here. If someone crashes + * with the old code and then boots with the new code, + * we might find a leaf here. + */ + if (*level == 0) { + ret = btrfs_drop_leaf_ref(trans, root, cur); + BUG_ON(ret); + break; } - btrfs_tree_unlock(eb); - free_extent_buffer(eb); + /* - * the first key is just a hint, so the race we've created - * against reading it is fine + * once we get to level one, process the whole node + * at once, including everything below it. */ - err = btrfs_insert_extent_backref(trans, extent_root, path, - start, extent_root->root_key.objectid, - 0, level, - btrfs_disk_key_objectid(&first)); - BUG_ON(err); - if (need_resched()) { - mutex_unlock(&extent_root->fs_info->alloc_mutex); - cond_resched(); - mutex_lock(&extent_root->fs_info->alloc_mutex); + if (*level == 1) { + ret = drop_level_one_refs(trans, root, path); + BUG_ON(ret); + break; } - } - btrfs_free_path(path); - return 0; -} -static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes, - int is_data, int pending) -{ - int err = 0; + bytenr = btrfs_node_blockptr(cur, path->slots[*level]); + ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]); + blocksize = btrfs_level_size(root, *level - 1); + + ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs); + BUG_ON(ret); - WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex)); - if (!pending) { - struct extent_buffer *buf; + /* + * if there is more than one reference, we don't need + * to read that node to drop any references it has. We + * just drop the ref we hold on that node and move on to the + * next slot in this level. + */ + if (refs != 1) { + parent = path->nodes[*level]; + root_owner = btrfs_header_owner(parent); + root_gen = btrfs_header_generation(parent); + path->slots[*level]++; - if (is_data) - goto pinit; + ret = __btrfs_free_extent(trans, root, bytenr, + blocksize, parent->start, + root_owner, root_gen, + *level - 1, 1); + BUG_ON(ret); - buf = btrfs_find_tree_block(root, bytenr, num_bytes); - if (buf) { - /* we can reuse a block if it hasn't been written - * and it is from this transaction. We can't - * reuse anything from the tree log root because - * it has tiny sub-transactions. - */ - if (btrfs_buffer_uptodate(buf, 0) && - btrfs_try_tree_lock(buf)) { - u64 transid = - root->fs_info->running_transaction->transid; - u64 header_transid = - btrfs_header_generation(buf); - if (btrfs_header_owner(buf) != - BTRFS_TREE_LOG_OBJECTID && - header_transid == transid && - !btrfs_header_flag(buf, - BTRFS_HEADER_FLAG_WRITTEN)) { - clean_tree_block(NULL, root, buf); - btrfs_tree_unlock(buf); - free_extent_buffer(buf); - return 1; - } - btrfs_tree_unlock(buf); - } - free_extent_buffer(buf); + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + cond_resched(); + + continue; } -pinit: - btrfs_update_pinned_extents(root, bytenr, num_bytes, 1); + + /* + * we need to keep freeing things in the next level down. + * read the block and loop around to process it + */ + next = read_tree_block(root, bytenr, blocksize, ptr_gen); + WARN_ON(*level <= 0); + if (path->nodes[*level-1]) + free_extent_buffer(path->nodes[*level-1]); + path->nodes[*level-1] = next; + *level = btrfs_header_level(next); + path->slots[*level] = 0; + cond_resched(); + } +out: + WARN_ON(*level < 0); + WARN_ON(*level >= BTRFS_MAX_LEVEL); + + if (path->nodes[*level] == root->node) { + parent = path->nodes[*level]; + bytenr = path->nodes[*level]->start; } else { - set_extent_bits(&root->fs_info->pending_del, - bytenr, bytenr + num_bytes - 1, - EXTENT_LOCKED, GFP_NOFS); + parent = path->nodes[*level + 1]; + bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]); } - BUG_ON(err < 0); + + blocksize = btrfs_level_size(root, *level); + root_owner = btrfs_header_owner(parent); + root_gen = btrfs_header_generation(parent); + + /* + * cleanup and free the reference on the last node + * we processed + */ + ret = __btrfs_free_extent(trans, root, bytenr, blocksize, + parent->start, root_owner, root_gen, + *level, 1); + free_extent_buffer(path->nodes[*level]); + path->nodes[*level] = NULL; + + *level += 1; + BUG_ON(ret); + + cond_resched(); return 0; } /* - * remove an extent from the root, returns 0 on success + * helper function for drop_subtree, this function is similar to + * walk_down_tree. The main difference is that it checks reference + * counts while tree blocks are locked. */ -static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root - *root, u64 bytenr, u64 num_bytes, - u64 root_objectid, u64 ref_generation, - u64 owner_objectid, u64 owner_offset, int pin, - int mark_free) +static noinline int walk_down_subtree(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, int *level) { - struct btrfs_path *path; - struct btrfs_key key; - struct btrfs_fs_info *info = root->fs_info; - struct btrfs_root *extent_root = info->extent_root; - struct extent_buffer *leaf; - int ret; - int extent_slot = 0; - int found_extent = 0; - int num_to_del = 1; - struct btrfs_extent_item *ei; + struct extent_buffer *next; + struct extent_buffer *cur; + struct extent_buffer *parent; + u64 bytenr; + u64 ptr_gen; + u32 blocksize; u32 refs; + int ret; - WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex)); - key.objectid = bytenr; - btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY); - key.offset = num_bytes; - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; - - path->reada = 1; - ret = lookup_extent_backref(trans, extent_root, path, - bytenr, root_objectid, - ref_generation, - owner_objectid, owner_offset, 1); - if (ret == 0) { - struct btrfs_key found_key; - extent_slot = path->slots[0]; - while(extent_slot > 0) { - extent_slot--; - btrfs_item_key_to_cpu(path->nodes[0], &found_key, - extent_slot); - if (found_key.objectid != bytenr) - break; - if (found_key.type == BTRFS_EXTENT_ITEM_KEY && - found_key.offset == num_bytes) { - found_extent = 1; - break; - } - if (path->slots[0] - extent_slot > 5) - break; - } - if (!found_extent) - ret = btrfs_del_item(trans, extent_root, path); - } else { - btrfs_print_leaf(extent_root, path->nodes[0]); - WARN_ON(1); - printk("Unable to find ref byte nr %Lu root %Lu " - " gen %Lu owner %Lu offset %Lu\n", bytenr, - root_objectid, ref_generation, owner_objectid, - owner_offset); - } - if (!found_extent) { - btrfs_release_path(extent_root, path); - ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1); - if (ret < 0) - return ret; - BUG_ON(ret); - extent_slot = path->slots[0]; - } - - leaf = path->nodes[0]; - ei = btrfs_item_ptr(leaf, extent_slot, - struct btrfs_extent_item); - refs = btrfs_extent_refs(leaf, ei); - BUG_ON(refs == 0); - refs -= 1; - btrfs_set_extent_refs(leaf, ei, refs); - - btrfs_mark_buffer_dirty(leaf); + cur = path->nodes[*level]; + ret = btrfs_lookup_extent_ref(trans, root, cur->start, cur->len, + &refs); + BUG_ON(ret); + if (refs > 1) + goto out; - if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) { - /* if the back ref and the extent are next to each other - * they get deleted below in one shot - */ - path->slots[0] = extent_slot; - num_to_del = 2; - } else if (found_extent) { - /* otherwise delete the extent back ref */ - ret = btrfs_del_item(trans, extent_root, path); - BUG_ON(ret); - /* if refs are 0, we need to setup the path for deletion */ - if (refs == 0) { - btrfs_release_path(extent_root, path); - ret = btrfs_search_slot(trans, extent_root, &key, path, - -1, 1); - if (ret < 0) - return ret; + while (*level >= 0) { + cur = path->nodes[*level]; + if (*level == 0) { + ret = btrfs_drop_leaf_ref(trans, root, cur); BUG_ON(ret); + clean_tree_block(trans, root, cur); + break; } - } - - if (refs == 0) { - u64 super_used; - u64 root_used; -#ifdef BIO_RW_DISCARD - u64 map_length = num_bytes; - struct btrfs_multi_bio *multi = NULL; -#endif - - if (pin) { - ret = pin_down_bytes(root, bytenr, num_bytes, - owner_objectid >= BTRFS_FIRST_FREE_OBJECTID, 0); - if (ret > 0) - mark_free = 1; - BUG_ON(ret < 0); + if (path->slots[*level] >= btrfs_header_nritems(cur)) { + clean_tree_block(trans, root, cur); + break; } - /* block accounting for super block */ - spin_lock_irq(&info->delalloc_lock); - super_used = btrfs_super_bytes_used(&info->super_copy); - btrfs_set_super_bytes_used(&info->super_copy, - super_used - num_bytes); - spin_unlock_irq(&info->delalloc_lock); - - /* block accounting for root item */ - root_used = btrfs_root_used(&root->root_item); - btrfs_set_root_used(&root->root_item, - root_used - num_bytes); - ret = btrfs_del_items(trans, extent_root, path, path->slots[0], - num_to_del); - if (ret) { - return ret; - } - ret = update_block_group(trans, root, bytenr, num_bytes, 0, - mark_free); + bytenr = btrfs_node_blockptr(cur, path->slots[*level]); + blocksize = btrfs_level_size(root, *level - 1); + ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]); + + next = read_tree_block(root, bytenr, blocksize, ptr_gen); + btrfs_tree_lock(next); + btrfs_set_lock_blocking(next); + + ret = btrfs_lookup_extent_ref(trans, root, bytenr, blocksize, + &refs); BUG_ON(ret); + if (refs > 1) { + parent = path->nodes[*level]; + ret = btrfs_free_extent(trans, root, bytenr, + blocksize, parent->start, + btrfs_header_owner(parent), + btrfs_header_generation(parent), + *level - 1, 1); + BUG_ON(ret); + path->slots[*level]++; + btrfs_tree_unlock(next); + free_extent_buffer(next); + continue; + } -#ifdef BIO_RW_DISCARD - /* Tell the block device(s) that the sectors can be discarded */ - ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, - bytenr, &map_length, &multi, 0); - if (!ret) { - struct btrfs_bio_stripe *stripe = multi->stripes; - int i; + *level = btrfs_header_level(next); + path->nodes[*level] = next; + path->slots[*level] = 0; + path->locks[*level] = 1; + cond_resched(); + } +out: + parent = path->nodes[*level + 1]; + bytenr = path->nodes[*level]->start; + blocksize = path->nodes[*level]->len; - if (map_length > num_bytes) - map_length = num_bytes; + ret = btrfs_free_extent(trans, root, bytenr, blocksize, + parent->start, btrfs_header_owner(parent), + btrfs_header_generation(parent), *level, 1); + BUG_ON(ret); - for (i = 0; i < multi->num_stripes; i++, stripe++) { - blkdev_issue_discard(stripe->dev->bdev, - stripe->physical >> 9, - map_length >> 9); - } - kfree(multi); - } -#endif + if (path->locks[*level]) { + btrfs_tree_unlock(path->nodes[*level]); + path->locks[*level] = 0; } - btrfs_free_path(path); - finish_current_insert(trans, extent_root); - return ret; + free_extent_buffer(path->nodes[*level]); + path->nodes[*level] = NULL; + *level += 1; + cond_resched(); + return 0; } /* - * find all the blocks marked as pending in the radix tree and remove - * them from the extent map + * helper for dropping snapshots. This walks back up the tree in the path + * to find the first node higher up where we haven't yet gone through + * all the slots */ -static int del_pending_extents(struct btrfs_trans_handle *trans, struct - btrfs_root *extent_root) +static noinline int walk_up_tree(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + int *level, int max_level) { + u64 root_owner; + u64 root_gen; + struct btrfs_root_item *root_item = &root->root_item; + int i; + int slot; int ret; - int err = 0; - u64 start; - u64 end; - struct extent_io_tree *pending_del; - struct extent_io_tree *pinned_extents; - WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex)); - pending_del = &extent_root->fs_info->pending_del; - pinned_extents = &extent_root->fs_info->pinned_extents; + for (i = *level; i < max_level && path->nodes[i]; i++) { + slot = path->slots[i]; + if (slot < btrfs_header_nritems(path->nodes[i]) - 1) { + struct extent_buffer *node; + struct btrfs_disk_key disk_key; - while(1) { - ret = find_first_extent_bit(pending_del, 0, &start, &end, - EXTENT_LOCKED); - if (ret) - break; - clear_extent_bits(pending_del, start, end, EXTENT_LOCKED, - GFP_NOFS); - if (!test_range_bit(&extent_root->fs_info->extent_ins, - start, end, EXTENT_LOCKED, 0)) { - btrfs_update_pinned_extents(extent_root, start, - end + 1 - start, 1); - ret = __free_extent(trans, extent_root, - start, end + 1 - start, - extent_root->root_key.objectid, - 0, 0, 0, 0, 0); + /* + * there is more work to do in this level. + * Update the drop_progress marker to reflect + * the work we've done so far, and then bump + * the slot number + */ + node = path->nodes[i]; + path->slots[i]++; + *level = i; + WARN_ON(*level == 0); + btrfs_node_key(node, &disk_key, path->slots[i]); + memcpy(&root_item->drop_progress, + &disk_key, sizeof(disk_key)); + root_item->drop_level = i; + return 0; } else { - clear_extent_bits(&extent_root->fs_info->extent_ins, - start, end, EXTENT_LOCKED, GFP_NOFS); - } - if (ret) - err = ret; + struct extent_buffer *parent; - if (need_resched()) { - mutex_unlock(&extent_root->fs_info->alloc_mutex); - cond_resched(); - mutex_lock(&extent_root->fs_info->alloc_mutex); + /* + * this whole node is done, free our reference + * on it and go up one level + */ + if (path->nodes[*level] == root->node) + parent = path->nodes[*level]; + else + parent = path->nodes[*level + 1]; + + root_owner = btrfs_header_owner(parent); + root_gen = btrfs_header_generation(parent); + + clean_tree_block(trans, root, path->nodes[*level]); + ret = btrfs_free_extent(trans, root, + path->nodes[*level]->start, + path->nodes[*level]->len, + parent->start, root_owner, + root_gen, *level, 1); + BUG_ON(ret); + if (path->locks[*level]) { + btrfs_tree_unlock(path->nodes[*level]); + path->locks[*level] = 0; + } + free_extent_buffer(path->nodes[*level]); + path->nodes[*level] = NULL; + *level = i + 1; } } - return err; + return 1; } /* - * remove an extent from the root, returns 0 on success + * drop the reference count on the tree rooted at 'snap'. This traverses + * the tree freeing any blocks that have a ref count of zero after being + * decremented. */ -static int __btrfs_free_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 bytenr, - u64 num_bytes, u64 root_objectid, - u64 ref_generation, u64 owner_objectid, - u64 owner_offset, int pin) +int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root + *root) { - struct btrfs_root *extent_root = root->fs_info->extent_root; - int pending_ret; - int ret; + int ret = 0; + int wret; + int level; + struct btrfs_path *path; + int i; + int orig_level; + struct btrfs_root_item *root_item = &root->root_item; - WARN_ON(num_bytes < root->sectorsize); - if (!root->ref_cows) - ref_generation = 0; + WARN_ON(!mutex_is_locked(&root->fs_info->drop_mutex)); + path = btrfs_alloc_path(); + BUG_ON(!path); - if (root == extent_root) { - pin_down_bytes(root, bytenr, num_bytes, 0, 1); - return 0; - } - /* if metadata always pin */ - if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) { - if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { - /* btrfs_free_reserved_extent */ - set_extent_dirty(&root->fs_info->free_space_cache, - bytenr, bytenr + num_bytes - 1, GFP_NOFS); - return 0; + level = btrfs_header_level(root->node); + orig_level = level; + if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { + path->nodes[level] = root->node; + extent_buffer_get(root->node); + path->slots[level] = 0; + } else { + struct btrfs_key key; + struct btrfs_disk_key found_key; + struct extent_buffer *node; + + btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); + level = root_item->drop_level; + path->lowest_level = level; + wret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (wret < 0) { + ret = wret; + goto out; + } + node = path->nodes[level]; + btrfs_node_key(node, &found_key, path->slots[level]); + WARN_ON(memcmp(&found_key, &root_item->drop_progress, + sizeof(found_key))); + /* + * unlock our path, this is safe because only this + * function is allowed to delete this snapshot + */ + for (i = 0; i < BTRFS_MAX_LEVEL; i++) { + if (path->nodes[i] && path->locks[i]) { + path->locks[i] = 0; + btrfs_tree_unlock(path->nodes[i]); + } } - pin = 1; } + while (1) { + wret = walk_down_tree(trans, root, path, &level); + if (wret > 0) + break; + if (wret < 0) + ret = wret; - /* if data pin when any transaction has committed this */ - if (ref_generation != trans->transid) - pin = 1; - - ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid, - ref_generation, owner_objectid, owner_offset, - pin, pin == 0); - - finish_current_insert(trans, root->fs_info->extent_root); - pending_ret = del_pending_extents(trans, root->fs_info->extent_root); - return ret ? ret : pending_ret; -} - -int btrfs_free_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 bytenr, - u64 num_bytes, u64 root_objectid, - u64 ref_generation, u64 owner_objectid, - u64 owner_offset, int pin) -{ - int ret; - - maybe_lock_mutex(root); - ret = __btrfs_free_extent(trans, root, bytenr, num_bytes, - root_objectid, ref_generation, - owner_objectid, owner_offset, pin); - maybe_unlock_mutex(root); + wret = walk_up_tree(trans, root, path, &level, + BTRFS_MAX_LEVEL); + if (wret > 0) + break; + if (wret < 0) + ret = wret; + if (trans->transaction->in_commit) { + ret = -EAGAIN; + break; + } + atomic_inc(&root->fs_info->throttle_gen); + wake_up(&root->fs_info->transaction_throttle); + } + for (i = 0; i <= orig_level; i++) { + if (path->nodes[i]) { + free_extent_buffer(path->nodes[i]); + path->nodes[i] = NULL; + } + } +out: + btrfs_free_path(path); return ret; } -static u64 stripe_align(struct btrfs_root *root, u64 val) +int btrfs_drop_subtree(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *node, + struct extent_buffer *parent) { - u64 mask = ((u64)root->stripesize - 1); - u64 ret = (val + mask) & ~mask; - return ret; -} + struct btrfs_path *path; + int level; + int parent_level; + int ret = 0; + int wret; -/* - * walks the btree of allocated extents and find a hole of a given size. - * The key ins is changed to record the hole: - * ins->objectid == block start - * ins->flags = BTRFS_EXTENT_ITEM_KEY - * ins->offset == number of blocks - * Any available blocks before search_start are skipped. - */ -static int noinline find_free_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *orig_root, - u64 num_bytes, u64 empty_size, - u64 search_start, u64 search_end, - u64 hint_byte, struct btrfs_key *ins, - u64 exclude_start, u64 exclude_nr, - int data) -{ - int ret; - u64 orig_search_start; - struct btrfs_root * root = orig_root->fs_info->extent_root; - struct btrfs_fs_info *info = root->fs_info; - u64 total_needed = num_bytes; - u64 *last_ptr = NULL; - struct btrfs_block_group_cache *block_group; - int full_scan = 0; - int wrapped = 0; - int chunk_alloc_done = 0; - int empty_cluster = 2 * 1024 * 1024; - int allowed_chunk_alloc = 0; + path = btrfs_alloc_path(); + BUG_ON(!path); - WARN_ON(num_bytes < root->sectorsize); - btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY); + BUG_ON(!btrfs_tree_locked(parent)); + parent_level = btrfs_header_level(parent); + extent_buffer_get(parent); + path->nodes[parent_level] = parent; + path->slots[parent_level] = btrfs_header_nritems(parent); - if (orig_root->ref_cows || empty_size) - allowed_chunk_alloc = 1; + BUG_ON(!btrfs_tree_locked(node)); + level = btrfs_header_level(node); + extent_buffer_get(node); + path->nodes[level] = node; + path->slots[level] = 0; - if (data & BTRFS_BLOCK_GROUP_METADATA) { - last_ptr = &root->fs_info->last_alloc; - empty_cluster = 256 * 1024; - } + while (1) { + wret = walk_down_subtree(trans, root, path, &level); + if (wret < 0) + ret = wret; + if (wret != 0) + break; - if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) { - last_ptr = &root->fs_info->last_data_alloc; - } - if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { - last_ptr = &root->fs_info->last_log_alloc; - if (!last_ptr == 0 && root->fs_info->last_alloc) { - *last_ptr = root->fs_info->last_alloc + empty_cluster; - } + wret = walk_up_tree(trans, root, path, &level, parent_level); + if (wret < 0) + ret = wret; + if (wret != 0) + break; } - if (last_ptr) { - if (*last_ptr) - hint_byte = *last_ptr; - else { - empty_size += empty_cluster; - } - } + btrfs_free_path(path); + return ret; +} - search_start = max(search_start, first_logical_byte(root, 0)); - orig_search_start = search_start; +static unsigned long calc_ra(unsigned long start, unsigned long last, + unsigned long nr) +{ + return min(last, start + nr - 1); +} - if (search_end == (u64)-1) - search_end = btrfs_super_total_bytes(&info->super_copy); +static noinline int relocate_inode_pages(struct inode *inode, u64 start, + u64 len) +{ + u64 page_start; + u64 page_end; + unsigned long first_index; + unsigned long last_index; + unsigned long i; + struct page *page; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; + struct file_ra_state *ra; + struct btrfs_ordered_extent *ordered; + unsigned int total_read = 0; + unsigned int total_dirty = 0; + int ret = 0; - if (hint_byte) { - block_group = btrfs_lookup_first_block_group(info, hint_byte); - if (!block_group) - hint_byte = search_start; - block_group = btrfs_find_block_group(root, block_group, - hint_byte, data, 1); - if (last_ptr && *last_ptr == 0 && block_group) - hint_byte = block_group->key.objectid; - } else { - block_group = btrfs_find_block_group(root, - trans->block_group, - search_start, data, 1); - } - search_start = max(search_start, hint_byte); + ra = kzalloc(sizeof(*ra), GFP_NOFS); - total_needed += empty_size; + mutex_lock(&inode->i_mutex); + first_index = start >> PAGE_CACHE_SHIFT; + last_index = (start + len - 1) >> PAGE_CACHE_SHIFT; -check_failed: - if (!block_group) { - block_group = btrfs_lookup_first_block_group(info, - search_start); - if (!block_group) - block_group = btrfs_lookup_first_block_group(info, - orig_search_start); - } - if (full_scan && !chunk_alloc_done) { - if (allowed_chunk_alloc) { - do_chunk_alloc(trans, root, - num_bytes + 2 * 1024 * 1024, data, 1); - allowed_chunk_alloc = 0; - } else if (block_group && block_group_bits(block_group, data)) { - block_group->space_info->force_alloc = 1; - } - chunk_alloc_done = 1; - } - ret = find_search_start(root, &block_group, &search_start, - total_needed, data); - if (ret == -ENOSPC && last_ptr && *last_ptr) { - *last_ptr = 0; - block_group = btrfs_lookup_first_block_group(info, - orig_search_start); - search_start = orig_search_start; - ret = find_search_start(root, &block_group, &search_start, - total_needed, data); - } - if (ret == -ENOSPC) - goto enospc; + /* make sure the dirty trick played by the caller work */ + ret = invalidate_inode_pages2_range(inode->i_mapping, + first_index, last_index); if (ret) - goto error; - - if (last_ptr && *last_ptr && search_start != *last_ptr) { - *last_ptr = 0; - if (!empty_size) { - empty_size += empty_cluster; - total_needed += empty_size; - } - block_group = btrfs_lookup_first_block_group(info, - orig_search_start); - search_start = orig_search_start; - ret = find_search_start(root, &block_group, - &search_start, total_needed, data); - if (ret == -ENOSPC) - goto enospc; - if (ret) - goto error; - } - - search_start = stripe_align(root, search_start); - ins->objectid = search_start; - ins->offset = num_bytes; + goto out_unlock; - if (ins->objectid + num_bytes >= search_end) - goto enospc; + file_ra_state_init(ra, inode->i_mapping); - if (ins->objectid + num_bytes > - block_group->key.objectid + block_group->key.offset) { - search_start = block_group->key.objectid + - block_group->key.offset; - goto new_group; - } + for (i = first_index ; i <= last_index; i++) { + if (total_read % ra->ra_pages == 0) { + btrfs_force_ra(inode->i_mapping, ra, NULL, i, + calc_ra(i, last_index, ra->ra_pages)); + } + total_read++; +again: + if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode)) + BUG_ON(1); + page = grab_cache_page(inode->i_mapping, i); + if (!page) { + ret = -ENOMEM; + goto out_unlock; + } + if (!PageUptodate(page)) { + btrfs_readpage(NULL, page); + lock_page(page); + if (!PageUptodate(page)) { + unlock_page(page); + page_cache_release(page); + ret = -EIO; + goto out_unlock; + } + } + wait_on_page_writeback(page); - if (test_range_bit(&info->extent_ins, ins->objectid, - ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) { - search_start = ins->objectid + num_bytes; - goto new_group; - } + page_start = (u64)page->index << PAGE_CACHE_SHIFT; + page_end = page_start + PAGE_CACHE_SIZE - 1; + lock_extent(io_tree, page_start, page_end, GFP_NOFS); - if (test_range_bit(&info->pinned_extents, ins->objectid, - ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) { - search_start = ins->objectid + num_bytes; - goto new_group; - } + ordered = btrfs_lookup_ordered_extent(inode, page_start); + if (ordered) { + unlock_extent(io_tree, page_start, page_end, GFP_NOFS); + unlock_page(page); + page_cache_release(page); + btrfs_start_ordered_extent(inode, ordered, 1); + btrfs_put_ordered_extent(ordered); + goto again; + } + set_page_extent_mapped(page); - if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start && - ins->objectid < exclude_start + exclude_nr)) { - search_start = exclude_start + exclude_nr; - goto new_group; - } + if (i == first_index) + set_extent_bits(io_tree, page_start, page_end, + EXTENT_BOUNDARY, GFP_NOFS); + btrfs_set_extent_delalloc(inode, page_start, page_end); - if (!(data & BTRFS_BLOCK_GROUP_DATA)) { - block_group = btrfs_lookup_block_group(info, ins->objectid); - if (block_group) - trans->block_group = block_group; - } - ins->offset = num_bytes; - if (last_ptr) { - *last_ptr = ins->objectid + ins->offset; - if (*last_ptr == - btrfs_super_total_bytes(&root->fs_info->super_copy)) { - *last_ptr = 0; - } - } - return 0; + set_page_dirty(page); + total_dirty++; -new_group: - if (search_start + num_bytes >= search_end) { -enospc: - search_start = orig_search_start; - if (full_scan) { - ret = -ENOSPC; - goto error; - } - if (wrapped) { - if (!full_scan) - total_needed -= empty_size; - full_scan = 1; - } else - wrapped = 1; + unlock_extent(io_tree, page_start, page_end, GFP_NOFS); + unlock_page(page); + page_cache_release(page); } - block_group = btrfs_lookup_first_block_group(info, search_start); - cond_resched(); - block_group = btrfs_find_block_group(root, block_group, - search_start, data, 0); - goto check_failed; -error: +out_unlock: + kfree(ra); + mutex_unlock(&inode->i_mutex); + balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty); return ret; } -static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 num_bytes, u64 min_alloc_size, - u64 empty_size, u64 hint_byte, - u64 search_end, struct btrfs_key *ins, - u64 data) +static noinline int relocate_data_extent(struct inode *reloc_inode, + struct btrfs_key *extent_key, + u64 offset) { - int ret; - u64 search_start = 0; - u64 alloc_profile; - struct btrfs_fs_info *info = root->fs_info; - - if (data) { - alloc_profile = info->avail_data_alloc_bits & - info->data_alloc_profile; - data = BTRFS_BLOCK_GROUP_DATA | alloc_profile; - } else if (root == root->fs_info->chunk_root) { - alloc_profile = info->avail_system_alloc_bits & - info->system_alloc_profile; - data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile; - } else { - alloc_profile = info->avail_metadata_alloc_bits & - info->metadata_alloc_profile; - data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile; - } -again: - data = reduce_alloc_profile(root, data); - /* - * the only place that sets empty_size is btrfs_realloc_node, which - * is not called recursively on allocations - */ - if (empty_size || root->ref_cows) { - if (!(data & BTRFS_BLOCK_GROUP_METADATA)) { - ret = do_chunk_alloc(trans, root->fs_info->extent_root, - 2 * 1024 * 1024, - BTRFS_BLOCK_GROUP_METADATA | - (info->metadata_alloc_profile & - info->avail_metadata_alloc_bits), 0); - BUG_ON(ret); + struct btrfs_root *root = BTRFS_I(reloc_inode)->root; + struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree; + struct extent_map *em; + u64 start = extent_key->objectid - offset; + u64 end = start + extent_key->offset - 1; + + em = alloc_extent_map(GFP_NOFS); + BUG_ON(!em || IS_ERR(em)); + + em->start = start; + em->len = extent_key->offset; + em->block_len = extent_key->offset; + em->block_start = extent_key->objectid; + em->bdev = root->fs_info->fs_devices->latest_bdev; + set_bit(EXTENT_FLAG_PINNED, &em->flags); + + /* setup extent map to cheat btrfs_readpage */ + lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS); + while (1) { + int ret; + spin_lock(&em_tree->lock); + ret = add_extent_mapping(em_tree, em); + spin_unlock(&em_tree->lock); + if (ret != -EEXIST) { + free_extent_map(em); + break; } - ret = do_chunk_alloc(trans, root->fs_info->extent_root, - num_bytes + 2 * 1024 * 1024, data, 0); - BUG_ON(ret); + btrfs_drop_extent_cache(reloc_inode, start, end, 0); } + unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS); - WARN_ON(num_bytes < root->sectorsize); - ret = find_free_extent(trans, root, num_bytes, empty_size, - search_start, search_end, hint_byte, ins, - trans->alloc_exclude_start, - trans->alloc_exclude_nr, data); - - if (ret == -ENOSPC && num_bytes > min_alloc_size) { - num_bytes = num_bytes >> 1; - num_bytes = max(num_bytes, min_alloc_size); - do_chunk_alloc(trans, root->fs_info->extent_root, - num_bytes, data, 1); - goto again; - } - if (ret) { - printk("allocation failed flags %Lu\n", data); - BUG(); - } - clear_extent_dirty(&root->fs_info->free_space_cache, - ins->objectid, ins->objectid + ins->offset - 1, - GFP_NOFS); - return 0; + return relocate_inode_pages(reloc_inode, start, extent_key->offset); } -int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len) -{ - maybe_lock_mutex(root); - set_extent_dirty(&root->fs_info->free_space_cache, - start, start + len - 1, GFP_NOFS); - maybe_unlock_mutex(root); - return 0; -} +struct btrfs_ref_path { + u64 extent_start; + u64 nodes[BTRFS_MAX_LEVEL]; + u64 root_objectid; + u64 root_generation; + u64 owner_objectid; + u32 num_refs; + int lowest_level; + int current_level; + int shared_level; + + struct btrfs_key node_keys[BTRFS_MAX_LEVEL]; + u64 new_nodes[BTRFS_MAX_LEVEL]; +}; + +struct disk_extent { + u64 ram_bytes; + u64 disk_bytenr; + u64 disk_num_bytes; + u64 offset; + u64 num_bytes; + u8 compression; + u8 encryption; + u16 other_encoding; +}; -int btrfs_reserve_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 num_bytes, u64 min_alloc_size, - u64 empty_size, u64 hint_byte, - u64 search_end, struct btrfs_key *ins, - u64 data) +static int is_cowonly_root(u64 root_objectid) { - int ret; - maybe_lock_mutex(root); - ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size, - empty_size, hint_byte, search_end, ins, - data); - maybe_unlock_mutex(root); - return ret; + if (root_objectid == BTRFS_ROOT_TREE_OBJECTID || + root_objectid == BTRFS_EXTENT_TREE_OBJECTID || + root_objectid == BTRFS_CHUNK_TREE_OBJECTID || + root_objectid == BTRFS_DEV_TREE_OBJECTID || + root_objectid == BTRFS_TREE_LOG_OBJECTID || + root_objectid == BTRFS_CSUM_TREE_OBJECTID) + return 1; + return 0; } -static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset, - struct btrfs_key *ins) +static noinline int __next_ref_path(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, + struct btrfs_ref_path *ref_path, + int first_time) { - int ret; - int pending_ret; - u64 super_used; - u64 root_used; - u64 num_bytes = ins->offset; - u32 sizes[2]; - struct btrfs_fs_info *info = root->fs_info; - struct btrfs_root *extent_root = info->extent_root; - struct btrfs_extent_item *extent_item; - struct btrfs_extent_ref *ref; + struct extent_buffer *leaf; struct btrfs_path *path; - struct btrfs_key keys[2]; + struct btrfs_extent_ref *ref; + struct btrfs_key key; + struct btrfs_key found_key; + u64 bytenr; + u32 nritems; + int level; + int ret = 1; - /* block accounting for super block */ - spin_lock_irq(&info->delalloc_lock); - super_used = btrfs_super_bytes_used(&info->super_copy); - btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes); - spin_unlock_irq(&info->delalloc_lock); + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; - /* block accounting for root item */ - root_used = btrfs_root_used(&root->root_item); - btrfs_set_root_used(&root->root_item, root_used + num_bytes); + if (first_time) { + ref_path->lowest_level = -1; + ref_path->current_level = -1; + ref_path->shared_level = -1; + goto walk_up; + } +walk_down: + level = ref_path->current_level - 1; + while (level >= -1) { + u64 parent; + if (level < ref_path->lowest_level) + break; - if (root == extent_root) { - set_extent_bits(&root->fs_info->extent_ins, ins->objectid, - ins->objectid + ins->offset - 1, - EXTENT_LOCKED, GFP_NOFS); - goto update_block; + if (level >= 0) + bytenr = ref_path->nodes[level]; + else + bytenr = ref_path->extent_start; + BUG_ON(bytenr == 0); + + parent = ref_path->nodes[level + 1]; + ref_path->nodes[level + 1] = 0; + ref_path->current_level = level; + BUG_ON(parent == 0); + + key.objectid = bytenr; + key.offset = parent + 1; + key.type = BTRFS_EXTENT_REF_KEY; + + ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0); + if (ret < 0) + goto out; + BUG_ON(ret == 0); + + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + if (path->slots[0] >= nritems) { + ret = btrfs_next_leaf(extent_root, path); + if (ret < 0) + goto out; + if (ret > 0) + goto next; + leaf = path->nodes[0]; + } + + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid == bytenr && + found_key.type == BTRFS_EXTENT_REF_KEY) { + if (level < ref_path->shared_level) + ref_path->shared_level = level; + goto found; + } +next: + level--; + btrfs_release_path(extent_root, path); + cond_resched(); } + /* reached lowest level */ + ret = 1; + goto out; +walk_up: + level = ref_path->current_level; + while (level < BTRFS_MAX_LEVEL - 1) { + u64 ref_objectid; - memcpy(&keys[0], ins, sizeof(*ins)); - keys[1].offset = hash_extent_ref(root_objectid, ref_generation, - owner, owner_offset); - keys[1].objectid = ins->objectid; - keys[1].type = BTRFS_EXTENT_REF_KEY; - sizes[0] = sizeof(*extent_item); - sizes[1] = sizeof(*ref); + if (level >= 0) + bytenr = ref_path->nodes[level]; + else + bytenr = ref_path->extent_start; - path = btrfs_alloc_path(); - BUG_ON(!path); + BUG_ON(bytenr == 0); - ret = btrfs_insert_empty_items(trans, extent_root, path, keys, - sizes, 2); + key.objectid = bytenr; + key.offset = 0; + key.type = BTRFS_EXTENT_REF_KEY; - BUG_ON(ret); - extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0], - struct btrfs_extent_item); - btrfs_set_extent_refs(path->nodes[0], extent_item, 1); - ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, - struct btrfs_extent_ref); + ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0); + if (ret < 0) + goto out; - btrfs_set_ref_root(path->nodes[0], ref, root_objectid); - btrfs_set_ref_generation(path->nodes[0], ref, ref_generation); - btrfs_set_ref_objectid(path->nodes[0], ref, owner); - btrfs_set_ref_offset(path->nodes[0], ref, owner_offset); + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + if (path->slots[0] >= nritems) { + ret = btrfs_next_leaf(extent_root, path); + if (ret < 0) + goto out; + if (ret > 0) { + /* the extent was freed by someone */ + if (ref_path->lowest_level == level) + goto out; + btrfs_release_path(extent_root, path); + goto walk_down; + } + leaf = path->nodes[0]; + } + + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.objectid != bytenr || + found_key.type != BTRFS_EXTENT_REF_KEY) { + /* the extent was freed by someone */ + if (ref_path->lowest_level == level) { + ret = 1; + goto out; + } + btrfs_release_path(extent_root, path); + goto walk_down; + } +found: + ref = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_extent_ref); + ref_objectid = btrfs_ref_objectid(leaf, ref); + if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) { + if (first_time) { + level = (int)ref_objectid; + BUG_ON(level >= BTRFS_MAX_LEVEL); + ref_path->lowest_level = level; + ref_path->current_level = level; + ref_path->nodes[level] = bytenr; + } else { + WARN_ON(ref_objectid != level); + } + } else { + WARN_ON(level != -1); + } + first_time = 0; - btrfs_mark_buffer_dirty(path->nodes[0]); + if (ref_path->lowest_level == level) { + ref_path->owner_objectid = ref_objectid; + ref_path->num_refs = btrfs_ref_num_refs(leaf, ref); + } - trans->alloc_exclude_start = 0; - trans->alloc_exclude_nr = 0; - btrfs_free_path(path); - finish_current_insert(trans, extent_root); - pending_ret = del_pending_extents(trans, extent_root); + /* + * the block is tree root or the block isn't in reference + * counted tree. + */ + if (found_key.objectid == found_key.offset || + is_cowonly_root(btrfs_ref_root(leaf, ref))) { + ref_path->root_objectid = btrfs_ref_root(leaf, ref); + ref_path->root_generation = + btrfs_ref_generation(leaf, ref); + if (level < 0) { + /* special reference from the tree log */ + ref_path->nodes[0] = found_key.offset; + ref_path->current_level = 0; + } + ret = 0; + goto out; + } - if (ret) - goto out; - if (pending_ret) { - ret = pending_ret; - goto out; - } + level++; + BUG_ON(ref_path->nodes[level] != 0); + ref_path->nodes[level] = found_key.offset; + ref_path->current_level = level; -update_block: - ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0); - if (ret) { - printk("update block group failed for %Lu %Lu\n", - ins->objectid, ins->offset); - BUG(); + /* + * the reference was created in the running transaction, + * no need to continue walking up. + */ + if (btrfs_ref_generation(leaf, ref) == trans->transid) { + ref_path->root_objectid = btrfs_ref_root(leaf, ref); + ref_path->root_generation = + btrfs_ref_generation(leaf, ref); + ret = 0; + goto out; + } + + btrfs_release_path(extent_root, path); + cond_resched(); } + /* reached max tree level, but no tree root found. */ + BUG(); out: + btrfs_free_path(path); return ret; } -int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset, - struct btrfs_key *ins) -{ - int ret; - maybe_lock_mutex(root); - ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid, - ref_generation, owner, - owner_offset, ins); - maybe_unlock_mutex(root); - return ret; -} - -/* - * this is used by the tree logging recovery code. It records that - * an extent has been allocated and makes sure to clear the free - * space cache bits as well - */ -int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset, - struct btrfs_key *ins) +static int btrfs_first_ref_path(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, + struct btrfs_ref_path *ref_path, + u64 extent_start) { - int ret; - struct btrfs_block_group_cache *block_group; - - maybe_lock_mutex(root); - block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid); - cache_block_group(root, block_group); + memset(ref_path, 0, sizeof(*ref_path)); + ref_path->extent_start = extent_start; - clear_extent_dirty(&root->fs_info->free_space_cache, - ins->objectid, ins->objectid + ins->offset - 1, - GFP_NOFS); - ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid, - ref_generation, owner, - owner_offset, ins); - maybe_unlock_mutex(root); - return ret; + return __next_ref_path(trans, extent_root, ref_path, 1); } -/* - * finds a free extent and does all the dirty work required for allocation - * returns the key for the extent through ins, and a tree buffer for - * the first block of the extent through buf. - * - * returns 0 if everything worked, non-zero otherwise. - */ -int btrfs_alloc_extent(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 num_bytes, u64 min_alloc_size, - u64 root_objectid, u64 ref_generation, - u64 owner, u64 owner_offset, - u64 empty_size, u64 hint_byte, - u64 search_end, struct btrfs_key *ins, u64 data) +static int btrfs_next_ref_path(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, + struct btrfs_ref_path *ref_path) { - int ret; - - maybe_lock_mutex(root); - - ret = __btrfs_reserve_extent(trans, root, num_bytes, - min_alloc_size, empty_size, hint_byte, - search_end, ins, data); - BUG_ON(ret); - if (root_objectid != BTRFS_TREE_LOG_OBJECTID) { - ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid, - ref_generation, owner, - owner_offset, ins); - BUG_ON(ret); - - } - maybe_unlock_mutex(root); - return ret; + return __next_ref_path(trans, extent_root, ref_path, 0); } -struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 bytenr, u32 blocksize) +static noinline int get_new_locations(struct inode *reloc_inode, + struct btrfs_key *extent_key, + u64 offset, int no_fragment, + struct disk_extent **extents, + int *nr_extents) { - struct extent_buffer *buf; + struct btrfs_root *root = BTRFS_I(reloc_inode)->root; + struct btrfs_path *path; + struct btrfs_file_extent_item *fi; + struct extent_buffer *leaf; + struct disk_extent *exts = *extents; + struct btrfs_key found_key; + u64 cur_pos; + u64 last_byte; + u32 nritems; + int nr = 0; + int max = *nr_extents; + int ret; - buf = btrfs_find_create_tree_block(root, bytenr, blocksize); - if (!buf) - return ERR_PTR(-ENOMEM); - btrfs_set_header_generation(buf, trans->transid); - btrfs_tree_lock(buf); - clean_tree_block(trans, root, buf); - btrfs_set_buffer_uptodate(buf); - if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) { - set_extent_dirty(&root->dirty_log_pages, buf->start, - buf->start + buf->len - 1, GFP_NOFS); - } else { - set_extent_dirty(&trans->transaction->dirty_pages, buf->start, - buf->start + buf->len - 1, GFP_NOFS); + WARN_ON(!no_fragment && *extents); + if (!exts) { + max = 1; + exts = kmalloc(sizeof(*exts) * max, GFP_NOFS); + if (!exts) + return -ENOMEM; } - trans->blocks_used++; - return buf; -} -/* - * helper function to allocate a block for a given tree - * returns the tree buffer or NULL. - */ -struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u32 blocksize, - u64 root_objectid, - u64 ref_generation, - u64 first_objectid, - int level, - u64 hint, - u64 empty_size) -{ - struct btrfs_key ins; - int ret; - struct extent_buffer *buf; + path = btrfs_alloc_path(); + BUG_ON(!path); - ret = btrfs_alloc_extent(trans, root, blocksize, blocksize, - root_objectid, ref_generation, - level, first_objectid, empty_size, hint, - (u64)-1, &ins, 0); - if (ret) { - BUG_ON(ret > 0); - return ERR_PTR(ret); + cur_pos = extent_key->objectid - offset; + last_byte = extent_key->objectid + extent_key->offset; + ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino, + cur_pos, 0); + if (ret < 0) + goto out; + if (ret > 0) { + ret = -ENOENT; + goto out; } - buf = btrfs_init_new_buffer(trans, root, ins.objectid, blocksize); - return buf; -} - -int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, struct extent_buffer *leaf) -{ - u64 leaf_owner; - u64 leaf_generation; - struct btrfs_key key; - struct btrfs_file_extent_item *fi; - int i; - int nritems; - int ret; + while (1) { + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + if (path->slots[0] >= nritems) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) + goto out; + if (ret > 0) + break; + leaf = path->nodes[0]; + } - BUG_ON(!btrfs_is_leaf(leaf)); - nritems = btrfs_header_nritems(leaf); - leaf_owner = btrfs_header_owner(leaf); - leaf_generation = btrfs_header_generation(leaf); + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + if (found_key.offset != cur_pos || + found_key.type != BTRFS_EXTENT_DATA_KEY || + found_key.objectid != reloc_inode->i_ino) + break; - for (i = 0; i < nritems; i++) { - u64 disk_bytenr; - cond_resched(); + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + if (btrfs_file_extent_type(leaf, fi) != + BTRFS_FILE_EXTENT_REG || + btrfs_file_extent_disk_bytenr(leaf, fi) == 0) + break; - btrfs_item_key_to_cpu(leaf, &key, i); - if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) - continue; - fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); - if (btrfs_file_extent_type(leaf, fi) == - BTRFS_FILE_EXTENT_INLINE) - continue; - /* - * FIXME make sure to insert a trans record that - * repeats the snapshot del on crash - */ - disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); - if (disk_bytenr == 0) - continue; + if (nr == max) { + struct disk_extent *old = exts; + max *= 2; + exts = kzalloc(sizeof(*exts) * max, GFP_NOFS); + memcpy(exts, old, sizeof(*exts) * nr); + if (old != *extents) + kfree(old); + } - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_free_extent(trans, root, disk_bytenr, - btrfs_file_extent_disk_num_bytes(leaf, fi), - leaf_owner, leaf_generation, - key.objectid, key.offset, 0); - mutex_unlock(&root->fs_info->alloc_mutex); + exts[nr].disk_bytenr = + btrfs_file_extent_disk_bytenr(leaf, fi); + exts[nr].disk_num_bytes = + btrfs_file_extent_disk_num_bytes(leaf, fi); + exts[nr].offset = btrfs_file_extent_offset(leaf, fi); + exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi); + exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); + exts[nr].compression = btrfs_file_extent_compression(leaf, fi); + exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi); + exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf, + fi); + BUG_ON(exts[nr].offset > 0); + BUG_ON(exts[nr].compression || exts[nr].encryption); + BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes); + + cur_pos += exts[nr].num_bytes; + nr++; + + if (cur_pos + offset >= last_byte) + break; - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); + if (no_fragment) { + ret = 1; + goto out; + } + path->slots[0]++; + } - BUG_ON(ret); + BUG_ON(cur_pos + offset > last_byte); + if (cur_pos + offset < last_byte) { + ret = -ENOENT; + goto out; } - return 0; + ret = 0; +out: + btrfs_free_path(path); + if (ret) { + if (exts != *extents) + kfree(exts); + } else { + *extents = exts; + *nr_extents = nr; + } + return ret; } -static int noinline cache_drop_leaf_ref(struct btrfs_trans_handle *trans, +static noinline int replace_one_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, - struct btrfs_leaf_ref *ref) + struct btrfs_path *path, + struct btrfs_key *extent_key, + struct btrfs_key *leaf_key, + struct btrfs_ref_path *ref_path, + struct disk_extent *new_extents, + int nr_extents) { - int i; + struct extent_buffer *leaf; + struct btrfs_file_extent_item *fi; + struct inode *inode = NULL; + struct btrfs_key key; + u64 lock_start = 0; + u64 lock_end = 0; + u64 num_bytes; + u64 ext_offset; + u64 search_end = (u64)-1; + u32 nritems; + int nr_scaned = 0; + int extent_locked = 0; + int extent_type; int ret; - struct btrfs_extent_info *info = ref->extents; - - for (i = 0; i < ref->nritems; i++) { - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_free_extent(trans, root, - info->bytenr, info->num_bytes, - ref->owner, ref->generation, - info->objectid, info->offset, 0); - mutex_unlock(&root->fs_info->alloc_mutex); - - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); - BUG_ON(ret); - info++; + memcpy(&key, leaf_key, sizeof(key)); + if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) { + if (key.objectid < ref_path->owner_objectid || + (key.objectid == ref_path->owner_objectid && + key.type < BTRFS_EXTENT_DATA_KEY)) { + key.objectid = ref_path->owner_objectid; + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = 0; + } } - return 0; -} + while (1) { + ret = btrfs_search_slot(trans, root, &key, path, 0, 1); + if (ret < 0) + goto out; -int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len, - u32 *refs) -{ - int ret; + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); +next: + if (extent_locked && ret > 0) { + /* + * the file extent item was modified by someone + * before the extent got locked. + */ + unlock_extent(&BTRFS_I(inode)->io_tree, lock_start, + lock_end, GFP_NOFS); + extent_locked = 0; + } - ret = lookup_extent_ref(NULL, root, start, len, refs); - BUG_ON(ret); + if (path->slots[0] >= nritems) { + if (++nr_scaned > 2) + break; -#if 0 // some debugging code in case we see problems here - /* if the refs count is one, it won't get increased again. But - * if the ref count is > 1, someone may be decreasing it at - * the same time we are. - */ - if (*refs != 1) { - struct extent_buffer *eb = NULL; - eb = btrfs_find_create_tree_block(root, start, len); - if (eb) - btrfs_tree_lock(eb); + BUG_ON(extent_locked); + ret = btrfs_next_leaf(root, path); + if (ret < 0) + goto out; + if (ret > 0) + break; + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + } - mutex_lock(&root->fs_info->alloc_mutex); - ret = lookup_extent_ref(NULL, root, start, len, refs); - BUG_ON(ret); - mutex_unlock(&root->fs_info->alloc_mutex); + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); - if (eb) { - btrfs_tree_unlock(eb); - free_extent_buffer(eb); - } - if (*refs == 1) { - printk("block %llu went down to one during drop_snap\n", - (unsigned long long)start); + if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) { + if ((key.objectid > ref_path->owner_objectid) || + (key.objectid == ref_path->owner_objectid && + key.type > BTRFS_EXTENT_DATA_KEY) || + key.offset >= search_end) + break; } - } -#endif + if (inode && key.objectid != inode->i_ino) { + BUG_ON(extent_locked); + btrfs_release_path(root, path); + mutex_unlock(&inode->i_mutex); + iput(inode); + inode = NULL; + continue; + } - cond_resched(); - return ret; -} + if (key.type != BTRFS_EXTENT_DATA_KEY) { + path->slots[0]++; + ret = 1; + goto next; + } + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + extent_type = btrfs_file_extent_type(leaf, fi); + if ((extent_type != BTRFS_FILE_EXTENT_REG && + extent_type != BTRFS_FILE_EXTENT_PREALLOC) || + (btrfs_file_extent_disk_bytenr(leaf, fi) != + extent_key->objectid)) { + path->slots[0]++; + ret = 1; + goto next; + } -/* - * helper function for drop_snapshot, this walks down the tree dropping ref - * counts as it goes. - */ -static int noinline walk_down_tree(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, int *level) -{ - u64 root_owner; - u64 root_gen; - u64 bytenr; - u64 ptr_gen; - struct extent_buffer *next; - struct extent_buffer *cur; - struct extent_buffer *parent; - struct btrfs_leaf_ref *ref; - u32 blocksize; - int ret; - u32 refs; + num_bytes = btrfs_file_extent_num_bytes(leaf, fi); + ext_offset = btrfs_file_extent_offset(leaf, fi); - WARN_ON(*level < 0); - WARN_ON(*level >= BTRFS_MAX_LEVEL); - ret = drop_snap_lookup_refcount(root, path->nodes[*level]->start, - path->nodes[*level]->len, &refs); - BUG_ON(ret); - if (refs > 1) - goto out; + if (search_end == (u64)-1) { + search_end = key.offset - ext_offset + + btrfs_file_extent_ram_bytes(leaf, fi); + } - /* - * walk down to the last node level and free all the leaves - */ - while(*level >= 0) { - WARN_ON(*level < 0); - WARN_ON(*level >= BTRFS_MAX_LEVEL); - cur = path->nodes[*level]; + if (!extent_locked) { + lock_start = key.offset; + lock_end = lock_start + num_bytes - 1; + } else { + if (lock_start > key.offset || + lock_end + 1 < key.offset + num_bytes) { + unlock_extent(&BTRFS_I(inode)->io_tree, + lock_start, lock_end, GFP_NOFS); + extent_locked = 0; + } + } - if (btrfs_header_level(cur) != *level) - WARN_ON(1); + if (!inode) { + btrfs_release_path(root, path); - if (path->slots[*level] >= - btrfs_header_nritems(cur)) - break; - if (*level == 0) { - ret = btrfs_drop_leaf_ref(trans, root, cur); - BUG_ON(ret); - break; + inode = btrfs_iget_locked(root->fs_info->sb, + key.objectid, root); + if (inode->i_state & I_NEW) { + BTRFS_I(inode)->root = root; + BTRFS_I(inode)->location.objectid = + key.objectid; + BTRFS_I(inode)->location.type = + BTRFS_INODE_ITEM_KEY; + BTRFS_I(inode)->location.offset = 0; + btrfs_read_locked_inode(inode); + unlock_new_inode(inode); + } + /* + * some code call btrfs_commit_transaction while + * holding the i_mutex, so we can't use mutex_lock + * here. + */ + if (is_bad_inode(inode) || + !mutex_trylock(&inode->i_mutex)) { + iput(inode); + inode = NULL; + key.offset = (u64)-1; + goto skip; + } } - bytenr = btrfs_node_blockptr(cur, path->slots[*level]); - ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]); - blocksize = btrfs_level_size(root, *level - 1); - ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs); - BUG_ON(ret); - if (refs != 1) { - parent = path->nodes[*level]; - root_owner = btrfs_header_owner(parent); - root_gen = btrfs_header_generation(parent); - path->slots[*level]++; + if (!extent_locked) { + struct btrfs_ordered_extent *ordered; - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_free_extent(trans, root, bytenr, - blocksize, root_owner, - root_gen, 0, 0, 1); - BUG_ON(ret); - mutex_unlock(&root->fs_info->alloc_mutex); + btrfs_release_path(root, path); - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); + lock_extent(&BTRFS_I(inode)->io_tree, lock_start, + lock_end, GFP_NOFS); + ordered = btrfs_lookup_first_ordered_extent(inode, + lock_end); + if (ordered && + ordered->file_offset <= lock_end && + ordered->file_offset + ordered->len > lock_start) { + unlock_extent(&BTRFS_I(inode)->io_tree, + lock_start, lock_end, GFP_NOFS); + btrfs_start_ordered_extent(inode, ordered, 1); + btrfs_put_ordered_extent(ordered); + key.offset += num_bytes; + goto skip; + } + if (ordered) + btrfs_put_ordered_extent(ordered); + extent_locked = 1; continue; } - /* - * at this point, we have a single ref, and since the - * only place referencing this extent is a dead root - * the reference count should never go higher. - * So, we don't need to check it again - */ - if (*level == 1) { - struct btrfs_key key; - btrfs_node_key_to_cpu(cur, &key, path->slots[*level]); - ref = btrfs_lookup_leaf_ref(root, bytenr); - if (ref) { - ret = cache_drop_leaf_ref(trans, root, ref); - BUG_ON(ret); - btrfs_remove_leaf_ref(root, ref); - btrfs_free_leaf_ref(root, ref); - *level = 0; - break; - } - if (printk_ratelimit()) - printk("leaf ref miss for bytenr %llu\n", - (unsigned long long)bytenr); - } - next = btrfs_find_tree_block(root, bytenr, blocksize); - if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) { - free_extent_buffer(next); - next = read_tree_block(root, bytenr, blocksize, - ptr_gen); - cond_resched(); + if (nr_extents == 1) { + /* update extent pointer in place */ + btrfs_set_file_extent_disk_bytenr(leaf, fi, + new_extents[0].disk_bytenr); + btrfs_set_file_extent_disk_num_bytes(leaf, fi, + new_extents[0].disk_num_bytes); + btrfs_mark_buffer_dirty(leaf); + + btrfs_drop_extent_cache(inode, key.offset, + key.offset + num_bytes - 1, 0); + + ret = btrfs_inc_extent_ref(trans, root, + new_extents[0].disk_bytenr, + new_extents[0].disk_num_bytes, + leaf->start, + root->root_key.objectid, + trans->transid, + key.objectid); + BUG_ON(ret); + + ret = btrfs_free_extent(trans, root, + extent_key->objectid, + extent_key->offset, + leaf->start, + btrfs_header_owner(leaf), + btrfs_header_generation(leaf), + key.objectid, 0); + BUG_ON(ret); + + btrfs_release_path(root, path); + key.offset += num_bytes; + } else { + BUG_ON(1); #if 0 + u64 alloc_hint; + u64 extent_len; + int i; /* - * this is a debugging check and can go away - * the ref should never go all the way down to 1 - * at this point + * drop old extent pointer at first, then insert the + * new pointers one bye one */ - ret = lookup_extent_ref(NULL, root, bytenr, blocksize, - &refs); + btrfs_release_path(root, path); + ret = btrfs_drop_extents(trans, root, inode, key.offset, + key.offset + num_bytes, + key.offset, &alloc_hint); BUG_ON(ret); - WARN_ON(refs != 1); -#endif - } - WARN_ON(*level <= 0); - if (path->nodes[*level-1]) - free_extent_buffer(path->nodes[*level-1]); - path->nodes[*level-1] = next; - *level = btrfs_header_level(next); - path->slots[*level] = 0; - cond_resched(); - } -out: - WARN_ON(*level < 0); - WARN_ON(*level >= BTRFS_MAX_LEVEL); - if (path->nodes[*level] == root->node) { - parent = path->nodes[*level]; - bytenr = path->nodes[*level]->start; - } else { - parent = path->nodes[*level + 1]; - bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]); - } + for (i = 0; i < nr_extents; i++) { + if (ext_offset >= new_extents[i].num_bytes) { + ext_offset -= new_extents[i].num_bytes; + continue; + } + extent_len = min(new_extents[i].num_bytes - + ext_offset, num_bytes); - blocksize = btrfs_level_size(root, *level); - root_owner = btrfs_header_owner(parent); - root_gen = btrfs_header_generation(parent); + ret = btrfs_insert_empty_item(trans, root, + path, &key, + sizeof(*fi)); + BUG_ON(ret); - mutex_lock(&root->fs_info->alloc_mutex); - ret = __btrfs_free_extent(trans, root, bytenr, blocksize, - root_owner, root_gen, 0, 0, 1); - free_extent_buffer(path->nodes[*level]); - path->nodes[*level] = NULL; - *level += 1; - BUG_ON(ret); - mutex_unlock(&root->fs_info->alloc_mutex); + leaf = path->nodes[0]; + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, fi, + trans->transid); + btrfs_set_file_extent_type(leaf, fi, + BTRFS_FILE_EXTENT_REG); + btrfs_set_file_extent_disk_bytenr(leaf, fi, + new_extents[i].disk_bytenr); + btrfs_set_file_extent_disk_num_bytes(leaf, fi, + new_extents[i].disk_num_bytes); + btrfs_set_file_extent_ram_bytes(leaf, fi, + new_extents[i].ram_bytes); + + btrfs_set_file_extent_compression(leaf, fi, + new_extents[i].compression); + btrfs_set_file_extent_encryption(leaf, fi, + new_extents[i].encryption); + btrfs_set_file_extent_other_encoding(leaf, fi, + new_extents[i].other_encoding); + + btrfs_set_file_extent_num_bytes(leaf, fi, + extent_len); + ext_offset += new_extents[i].offset; + btrfs_set_file_extent_offset(leaf, fi, + ext_offset); + btrfs_mark_buffer_dirty(leaf); + + btrfs_drop_extent_cache(inode, key.offset, + key.offset + extent_len - 1, 0); + + ret = btrfs_inc_extent_ref(trans, root, + new_extents[i].disk_bytenr, + new_extents[i].disk_num_bytes, + leaf->start, + root->root_key.objectid, + trans->transid, key.objectid); + BUG_ON(ret); + btrfs_release_path(root, path); - cond_resched(); - return 0; -} + inode_add_bytes(inode, extent_len); -/* - * helper for dropping snapshots. This walks back up the tree in the path - * to find the first node higher up where we haven't yet gone through - * all the slots - */ -static int noinline walk_up_tree(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, int *level) -{ - u64 root_owner; - u64 root_gen; - struct btrfs_root_item *root_item = &root->root_item; - int i; - int slot; - int ret; + ext_offset = 0; + num_bytes -= extent_len; + key.offset += extent_len; - for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { - slot = path->slots[i]; - if (slot < btrfs_header_nritems(path->nodes[i]) - 1) { - struct extent_buffer *node; - struct btrfs_disk_key disk_key; - node = path->nodes[i]; - path->slots[i]++; - *level = i; - WARN_ON(*level == 0); - btrfs_node_key(node, &disk_key, path->slots[i]); - memcpy(&root_item->drop_progress, - &disk_key, sizeof(disk_key)); - root_item->drop_level = i; - return 0; - } else { - if (path->nodes[*level] == root->node) { - root_owner = root->root_key.objectid; - root_gen = - btrfs_header_generation(path->nodes[*level]); - } else { - struct extent_buffer *node; - node = path->nodes[*level + 1]; - root_owner = btrfs_header_owner(node); - root_gen = btrfs_header_generation(node); + if (num_bytes == 0) + break; } - ret = btrfs_free_extent(trans, root, - path->nodes[*level]->start, - path->nodes[*level]->len, - root_owner, root_gen, 0, 0, 1); - BUG_ON(ret); - free_extent_buffer(path->nodes[*level]); - path->nodes[*level] = NULL; - *level = i + 1; + BUG_ON(i >= nr_extents); +#endif + } + + if (extent_locked) { + unlock_extent(&BTRFS_I(inode)->io_tree, lock_start, + lock_end, GFP_NOFS); + extent_locked = 0; } +skip: + if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS && + key.offset >= search_end) + break; + + cond_resched(); } - return 1; + ret = 0; +out: + btrfs_release_path(root, path); + if (inode) { + mutex_unlock(&inode->i_mutex); + if (extent_locked) { + unlock_extent(&BTRFS_I(inode)->io_tree, lock_start, + lock_end, GFP_NOFS); + } + iput(inode); + } + return ret; } -/* - * drop the reference count on the tree rooted at 'snap'. This traverses - * the tree freeing any blocks that have a ref count of zero after being - * decremented. - */ -int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root - *root) +int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *buf, u64 orig_start) { - int ret = 0; - int wret; int level; - struct btrfs_path *path; - int i; - int orig_level; - struct btrfs_root_item *root_item = &root->root_item; + int ret; - WARN_ON(!mutex_is_locked(&root->fs_info->drop_mutex)); - path = btrfs_alloc_path(); - BUG_ON(!path); + BUG_ON(btrfs_header_generation(buf) != trans->transid); + BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); - level = btrfs_header_level(root->node); - orig_level = level; - if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { - path->nodes[level] = root->node; - extent_buffer_get(root->node); - path->slots[level] = 0; - } else { - struct btrfs_key key; - struct btrfs_disk_key found_key; - struct extent_buffer *node; + level = btrfs_header_level(buf); + if (level == 0) { + struct btrfs_leaf_ref *ref; + struct btrfs_leaf_ref *orig_ref; - btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); - level = root_item->drop_level; - path->lowest_level = level; - wret = btrfs_search_slot(NULL, root, &key, path, 0, 0); - if (wret < 0) { - ret = wret; - goto out; - } - node = path->nodes[level]; - btrfs_node_key(node, &found_key, path->slots[level]); - WARN_ON(memcmp(&found_key, &root_item->drop_progress, - sizeof(found_key))); - /* - * unlock our path, this is safe because only this - * function is allowed to delete this snapshot - */ - for (i = 0; i < BTRFS_MAX_LEVEL; i++) { - if (path->nodes[i] && path->locks[i]) { - path->locks[i] = 0; - btrfs_tree_unlock(path->nodes[i]); - } + orig_ref = btrfs_lookup_leaf_ref(root, orig_start); + if (!orig_ref) + return -ENOENT; + + ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems); + if (!ref) { + btrfs_free_leaf_ref(root, orig_ref); + return -ENOMEM; } - } - while(1) { - wret = walk_down_tree(trans, root, path, &level); - if (wret > 0) - break; - if (wret < 0) - ret = wret; - wret = walk_up_tree(trans, root, path, &level); - if (wret > 0) - break; - if (wret < 0) - ret = wret; - if (trans->transaction->in_commit) { - ret = -EAGAIN; - break; + ref->nritems = orig_ref->nritems; + memcpy(ref->extents, orig_ref->extents, + sizeof(ref->extents[0]) * ref->nritems); + + btrfs_free_leaf_ref(root, orig_ref); + + ref->root_gen = trans->transid; + ref->bytenr = buf->start; + ref->owner = btrfs_header_owner(buf); + ref->generation = btrfs_header_generation(buf); + + ret = btrfs_add_leaf_ref(root, ref, 0); + WARN_ON(ret); + btrfs_free_leaf_ref(root, ref); + } + return 0; +} + +static noinline int invalidate_extent_cache(struct btrfs_root *root, + struct extent_buffer *leaf, + struct btrfs_block_group_cache *group, + struct btrfs_root *target_root) +{ + struct btrfs_key key; + struct inode *inode = NULL; + struct btrfs_file_extent_item *fi; + u64 num_bytes; + u64 skip_objectid = 0; + u32 nritems; + u32 i; + + nritems = btrfs_header_nritems(leaf); + for (i = 0; i < nritems; i++) { + btrfs_item_key_to_cpu(leaf, &key, i); + if (key.objectid == skip_objectid || + key.type != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); + if (btrfs_file_extent_type(leaf, fi) == + BTRFS_FILE_EXTENT_INLINE) + continue; + if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0) + continue; + if (!inode || inode->i_ino != key.objectid) { + iput(inode); + inode = btrfs_ilookup(target_root->fs_info->sb, + key.objectid, target_root, 1); } - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - } - for (i = 0; i <= orig_level; i++) { - if (path->nodes[i]) { - free_extent_buffer(path->nodes[i]); - path->nodes[i] = NULL; + if (!inode) { + skip_objectid = key.objectid; + continue; } + num_bytes = btrfs_file_extent_num_bytes(leaf, fi); + + lock_extent(&BTRFS_I(inode)->io_tree, key.offset, + key.offset + num_bytes - 1, GFP_NOFS); + btrfs_drop_extent_cache(inode, key.offset, + key.offset + num_bytes - 1, 1); + unlock_extent(&BTRFS_I(inode)->io_tree, key.offset, + key.offset + num_bytes - 1, GFP_NOFS); + cond_resched(); } -out: - btrfs_free_path(path); - return ret; + iput(inode); + return 0; } -int btrfs_free_block_groups(struct btrfs_fs_info *info) +static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct extent_buffer *leaf, + struct btrfs_block_group_cache *group, + struct inode *reloc_inode) { - u64 start; - u64 end; - u64 ptr; + struct btrfs_key key; + struct btrfs_key extent_key; + struct btrfs_file_extent_item *fi; + struct btrfs_leaf_ref *ref; + struct disk_extent *new_extent; + u64 bytenr; + u64 num_bytes; + u32 nritems; + u32 i; + int ext_index; + int nr_extent; int ret; - mutex_lock(&info->alloc_mutex); - while(1) { - ret = find_first_extent_bit(&info->block_group_cache, 0, - &start, &end, (unsigned int)-1); - if (ret) - break; - ret = get_state_private(&info->block_group_cache, start, &ptr); - if (!ret) - kfree((void *)(unsigned long)ptr); - clear_extent_bits(&info->block_group_cache, start, - end, (unsigned int)-1, GFP_NOFS); - } - while(1) { - ret = find_first_extent_bit(&info->free_space_cache, 0, - &start, &end, EXTENT_DIRTY); - if (ret) - break; - clear_extent_dirty(&info->free_space_cache, start, - end, GFP_NOFS); + new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS); + BUG_ON(!new_extent); + + ref = btrfs_lookup_leaf_ref(root, leaf->start); + BUG_ON(!ref); + + ext_index = -1; + nritems = btrfs_header_nritems(leaf); + for (i = 0; i < nritems; i++) { + btrfs_item_key_to_cpu(leaf, &key, i); + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); + if (btrfs_file_extent_type(leaf, fi) == + BTRFS_FILE_EXTENT_INLINE) + continue; + bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); + num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); + if (bytenr == 0) + continue; + + ext_index++; + if (bytenr >= group->key.objectid + group->key.offset || + bytenr + num_bytes <= group->key.objectid) + continue; + + extent_key.objectid = bytenr; + extent_key.offset = num_bytes; + extent_key.type = BTRFS_EXTENT_ITEM_KEY; + nr_extent = 1; + ret = get_new_locations(reloc_inode, &extent_key, + group->key.objectid, 1, + &new_extent, &nr_extent); + if (ret > 0) + continue; + BUG_ON(ret < 0); + + BUG_ON(ref->extents[ext_index].bytenr != bytenr); + BUG_ON(ref->extents[ext_index].num_bytes != num_bytes); + ref->extents[ext_index].bytenr = new_extent->disk_bytenr; + ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes; + + btrfs_set_file_extent_disk_bytenr(leaf, fi, + new_extent->disk_bytenr); + btrfs_set_file_extent_disk_num_bytes(leaf, fi, + new_extent->disk_num_bytes); + btrfs_mark_buffer_dirty(leaf); + + ret = btrfs_inc_extent_ref(trans, root, + new_extent->disk_bytenr, + new_extent->disk_num_bytes, + leaf->start, + root->root_key.objectid, + trans->transid, key.objectid); + BUG_ON(ret); + ret = btrfs_free_extent(trans, root, + bytenr, num_bytes, leaf->start, + btrfs_header_owner(leaf), + btrfs_header_generation(leaf), + key.objectid, 0); + BUG_ON(ret); + cond_resched(); } - mutex_unlock(&info->alloc_mutex); + kfree(new_extent); + BUG_ON(ext_index + 1 != ref->nritems); + btrfs_free_leaf_ref(root, ref); return 0; } -static unsigned long calc_ra(unsigned long start, unsigned long last, - unsigned long nr) +int btrfs_free_reloc_root(struct btrfs_trans_handle *trans, + struct btrfs_root *root) { - return min(last, start + nr - 1); + struct btrfs_root *reloc_root; + int ret; + + if (root->reloc_root) { + reloc_root = root->reloc_root; + root->reloc_root = NULL; + list_add(&reloc_root->dead_list, + &root->fs_info->dead_reloc_roots); + + btrfs_set_root_bytenr(&reloc_root->root_item, + reloc_root->node->start); + btrfs_set_root_level(&root->root_item, + btrfs_header_level(reloc_root->node)); + memset(&reloc_root->root_item.drop_progress, 0, + sizeof(struct btrfs_disk_key)); + reloc_root->root_item.drop_level = 0; + + ret = btrfs_update_root(trans, root->fs_info->tree_root, + &reloc_root->root_key, + &reloc_root->root_item); + BUG_ON(ret); + } + return 0; } -static int noinline relocate_inode_pages(struct inode *inode, u64 start, - u64 len) +int btrfs_drop_dead_reloc_roots(struct btrfs_root *root) { - u64 page_start; - u64 page_end; - unsigned long last_index; - unsigned long i; - struct page *page; - struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; - struct file_ra_state *ra; - unsigned long total_read = 0; - unsigned long ra_pages; - struct btrfs_ordered_extent *ordered; struct btrfs_trans_handle *trans; + struct btrfs_root *reloc_root; + struct btrfs_root *prev_root = NULL; + struct list_head dead_roots; + int ret; + unsigned long nr; - ra = kzalloc(sizeof(*ra), GFP_NOFS); + INIT_LIST_HEAD(&dead_roots); + list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots); - mutex_lock(&inode->i_mutex); - i = start >> PAGE_CACHE_SHIFT; - last_index = (start + len - 1) >> PAGE_CACHE_SHIFT; + while (!list_empty(&dead_roots)) { + reloc_root = list_entry(dead_roots.prev, + struct btrfs_root, dead_list); + list_del_init(&reloc_root->dead_list); - ra_pages = BTRFS_I(inode)->root->fs_info->bdi.ra_pages; + BUG_ON(reloc_root->commit_root != NULL); + while (1) { + trans = btrfs_join_transaction(root, 1); + BUG_ON(!trans); - file_ra_state_init(ra, inode->i_mapping); + mutex_lock(&root->fs_info->drop_mutex); + ret = btrfs_drop_snapshot(trans, reloc_root); + if (ret != -EAGAIN) + break; + mutex_unlock(&root->fs_info->drop_mutex); - for (; i <= last_index; i++) { - if (total_read % ra_pages == 0) { - btrfs_force_ra(inode->i_mapping, ra, NULL, i, - calc_ra(i, last_index, ra_pages)); - } - total_read++; -again: - if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode)) - goto truncate_racing; - page = grab_cache_page(inode->i_mapping, i); - if (!page) { - goto out_unlock; - } - if (!PageUptodate(page)) { - btrfs_readpage(NULL, page); - lock_page(page); - if (!PageUptodate(page)) { - unlock_page(page); - page_cache_release(page); - goto out_unlock; - } + nr = trans->blocks_used; + ret = btrfs_end_transaction(trans, root); + BUG_ON(ret); + btrfs_btree_balance_dirty(root, nr); } - wait_on_page_writeback(page); - - page_start = (u64)page->index << PAGE_CACHE_SHIFT; - page_end = page_start + PAGE_CACHE_SIZE - 1; - lock_extent(io_tree, page_start, page_end, GFP_NOFS); - ordered = btrfs_lookup_ordered_extent(inode, page_start); - if (ordered) { - unlock_extent(io_tree, page_start, page_end, GFP_NOFS); - unlock_page(page); - page_cache_release(page); - btrfs_start_ordered_extent(inode, ordered, 1); - btrfs_put_ordered_extent(ordered); - goto again; - } - set_page_extent_mapped(page); + free_extent_buffer(reloc_root->node); - /* - * make sure page_mkwrite is called for this page if userland - * wants to change it from mmap - */ - clear_page_dirty_for_io(page); + ret = btrfs_del_root(trans, root->fs_info->tree_root, + &reloc_root->root_key); + BUG_ON(ret); + mutex_unlock(&root->fs_info->drop_mutex); - btrfs_set_extent_delalloc(inode, page_start, page_end); - set_page_dirty(page); + nr = trans->blocks_used; + ret = btrfs_end_transaction(trans, root); + BUG_ON(ret); + btrfs_btree_balance_dirty(root, nr); - unlock_extent(io_tree, page_start, page_end, GFP_NOFS); - unlock_page(page); - page_cache_release(page); + kfree(prev_root); + prev_root = reloc_root; } - -out_unlock: - /* we have to start the IO in order to get the ordered extents - * instantiated. This allows the relocation to code to wait - * for all the ordered extents to hit the disk. - * - * Otherwise, it would constantly loop over the same extents - * because the old ones don't get deleted until the IO is - * started - */ - btrfs_fdatawrite_range(inode->i_mapping, start, start + len - 1, - WB_SYNC_NONE); - kfree(ra); - trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1); - if (trans) { - btrfs_end_transaction(trans, BTRFS_I(inode)->root); - mark_inode_dirty(inode); + if (prev_root) { + btrfs_remove_leaf_refs(prev_root, (u64)-1, 0); + kfree(prev_root); } - mutex_unlock(&inode->i_mutex); return 0; +} -truncate_racing: - vmtruncate(inode, inode->i_size); - balance_dirty_pages_ratelimited_nr(inode->i_mapping, - total_read); - goto out_unlock; +int btrfs_add_dead_reloc_root(struct btrfs_root *root) +{ + list_add(&root->dead_list, &root->fs_info->dead_reloc_roots); + return 0; } -/* - * The back references tell us which tree holds a ref on a block, - * but it is possible for the tree root field in the reference to - * reflect the original root before a snapshot was made. In this - * case we should search through all the children of a given root - * to find potential holders of references on a block. - * - * Instead, we do something a little less fancy and just search - * all the roots for a given key/block combination. - */ -static int find_root_for_ref(struct btrfs_root *root, - struct btrfs_path *path, - struct btrfs_key *key0, - int level, - int file_key, - struct btrfs_root **found_root, - u64 bytenr) -{ - struct btrfs_key root_location; - struct btrfs_root *cur_root = *found_root; - struct btrfs_file_extent_item *file_extent; - u64 root_search_start = BTRFS_FS_TREE_OBJECTID; - u64 found_bytenr; +int btrfs_cleanup_reloc_trees(struct btrfs_root *root) +{ + struct btrfs_root *reloc_root; + struct btrfs_trans_handle *trans; + struct btrfs_key location; + int found; int ret; - root_location.offset = (u64)-1; - root_location.type = BTRFS_ROOT_ITEM_KEY; - path->lowest_level = level; - path->reada = 0; - while(1) { - ret = btrfs_search_slot(NULL, cur_root, key0, path, 0, 0); - found_bytenr = 0; - if (ret == 0 && file_key) { - struct extent_buffer *leaf = path->nodes[0]; - file_extent = btrfs_item_ptr(leaf, path->slots[0], - struct btrfs_file_extent_item); - if (btrfs_file_extent_type(leaf, file_extent) == - BTRFS_FILE_EXTENT_REG) { - found_bytenr = - btrfs_file_extent_disk_bytenr(leaf, - file_extent); - } - } else if (!file_key) { - if (path->nodes[level]) - found_bytenr = path->nodes[level]->start; - } - - btrfs_release_path(cur_root, path); - - if (found_bytenr == bytenr) { - *found_root = cur_root; - ret = 0; - goto out; - } - ret = btrfs_search_root(root->fs_info->tree_root, - root_search_start, &root_search_start); - if (ret) - break; + mutex_lock(&root->fs_info->tree_reloc_mutex); + ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL); + BUG_ON(ret); + found = !list_empty(&root->fs_info->dead_reloc_roots); + mutex_unlock(&root->fs_info->tree_reloc_mutex); - root_location.objectid = root_search_start; - cur_root = btrfs_read_fs_root_no_name(root->fs_info, - &root_location); - if (!cur_root) { - ret = 1; - break; - } + if (found) { + trans = btrfs_start_transaction(root, 1); + BUG_ON(!trans); + ret = btrfs_commit_transaction(trans, root); + BUG_ON(ret); } -out: - path->lowest_level = 0; - return ret; + + location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID; + location.offset = (u64)-1; + location.type = BTRFS_ROOT_ITEM_KEY; + + reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location); + BUG_ON(!reloc_root); + btrfs_orphan_cleanup(reloc_root); + return 0; } -/* - * note, this releases the path - */ -static int noinline relocate_one_reference(struct btrfs_root *extent_root, - struct btrfs_path *path, - struct btrfs_key *extent_key, - u64 *last_file_objectid, - u64 *last_file_offset, - u64 *last_file_root, - u64 last_extent) -{ - struct inode *inode; - struct btrfs_root *found_root; - struct btrfs_key root_location; - struct btrfs_key found_key; - struct btrfs_extent_ref *ref; - u64 ref_root; - u64 ref_gen; - u64 ref_objectid; - u64 ref_offset; +static noinline int init_reloc_tree(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + struct btrfs_root *reloc_root; + struct extent_buffer *eb; + struct btrfs_root_item *root_item; + struct btrfs_key root_key; int ret; - int level; - WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex)); + BUG_ON(!root->ref_cows); + if (root->reloc_root) + return 0; - ref = btrfs_item_ptr(path->nodes[0], path->slots[0], - struct btrfs_extent_ref); - ref_root = btrfs_ref_root(path->nodes[0], ref); - ref_gen = btrfs_ref_generation(path->nodes[0], ref); - ref_objectid = btrfs_ref_objectid(path->nodes[0], ref); - ref_offset = btrfs_ref_offset(path->nodes[0], ref); - btrfs_release_path(extent_root, path); + root_item = kmalloc(sizeof(*root_item), GFP_NOFS); + BUG_ON(!root_item); - root_location.objectid = ref_root; - if (ref_gen == 0) - root_location.offset = 0; - else - root_location.offset = (u64)-1; - root_location.type = BTRFS_ROOT_ITEM_KEY; - - found_root = btrfs_read_fs_root_no_name(extent_root->fs_info, - &root_location); - BUG_ON(!found_root); - mutex_unlock(&extent_root->fs_info->alloc_mutex); - - if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) { - found_key.objectid = ref_objectid; - found_key.type = BTRFS_EXTENT_DATA_KEY; - found_key.offset = ref_offset; - level = 0; - - if (last_extent == extent_key->objectid && - *last_file_objectid == ref_objectid && - *last_file_offset == ref_offset && - *last_file_root == ref_root) - goto out; + ret = btrfs_copy_root(trans, root, root->commit_root, + &eb, BTRFS_TREE_RELOC_OBJECTID); + BUG_ON(ret); - ret = find_root_for_ref(extent_root, path, &found_key, - level, 1, &found_root, - extent_key->objectid); + root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; + root_key.offset = root->root_key.objectid; + root_key.type = BTRFS_ROOT_ITEM_KEY; - if (ret) - goto out; + memcpy(root_item, &root->root_item, sizeof(root_item)); + btrfs_set_root_refs(root_item, 0); + btrfs_set_root_bytenr(root_item, eb->start); + btrfs_set_root_level(root_item, btrfs_header_level(eb)); + btrfs_set_root_generation(root_item, trans->transid); - if (last_extent == extent_key->objectid && - *last_file_objectid == ref_objectid && - *last_file_offset == ref_offset && - *last_file_root == ref_root) - goto out; + btrfs_tree_unlock(eb); + free_extent_buffer(eb); + + ret = btrfs_insert_root(trans, root->fs_info->tree_root, + &root_key, root_item); + BUG_ON(ret); + kfree(root_item); - inode = btrfs_iget_locked(extent_root->fs_info->sb, - ref_objectid, found_root); - if (inode->i_state & I_NEW) { - /* the inode and parent dir are two different roots */ - BTRFS_I(inode)->root = found_root; - BTRFS_I(inode)->location.objectid = ref_objectid; - BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY; - BTRFS_I(inode)->location.offset = 0; - btrfs_read_locked_inode(inode); - unlock_new_inode(inode); + reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root, + &root_key); + BUG_ON(!reloc_root); + reloc_root->last_trans = trans->transid; + reloc_root->commit_root = NULL; + reloc_root->ref_tree = &root->fs_info->reloc_ref_tree; - } - /* this can happen if the reference is not against - * the latest version of the tree root - */ - if (is_bad_inode(inode)) - goto out; + root->reloc_root = reloc_root; + return 0; +} - *last_file_objectid = inode->i_ino; - *last_file_root = found_root->root_key.objectid; - *last_file_offset = ref_offset; +/* + * Core function of space balance. + * + * The idea is using reloc trees to relocate tree blocks in reference + * counted roots. There is one reloc tree for each subvol, and all + * reloc trees share same root key objectid. Reloc trees are snapshots + * of the latest committed roots of subvols (root->commit_root). + * + * To relocate a tree block referenced by a subvol, there are two steps. + * COW the block through subvol's reloc tree, then update block pointer + * in the subvol to point to the new block. Since all reloc trees share + * same root key objectid, doing special handing for tree blocks owned + * by them is easy. Once a tree block has been COWed in one reloc tree, + * we can use the resulting new block directly when the same block is + * required to COW again through other reloc trees. By this way, relocated + * tree blocks are shared between reloc trees, so they are also shared + * between subvols. + */ +static noinline int relocate_one_path(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_key *first_key, + struct btrfs_ref_path *ref_path, + struct btrfs_block_group_cache *group, + struct inode *reloc_inode) +{ + struct btrfs_root *reloc_root; + struct extent_buffer *eb = NULL; + struct btrfs_key *keys; + u64 *nodes; + int level; + int shared_level; + int lowest_level = 0; + int ret; - relocate_inode_pages(inode, ref_offset, extent_key->offset); - iput(inode); - } else { - struct btrfs_trans_handle *trans; - struct extent_buffer *eb; - int needs_lock = 0; + if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID) + lowest_level = ref_path->owner_objectid; - eb = read_tree_block(found_root, extent_key->objectid, - extent_key->offset, 0); - btrfs_tree_lock(eb); - level = btrfs_header_level(eb); + if (!root->ref_cows) { + path->lowest_level = lowest_level; + ret = btrfs_search_slot(trans, root, first_key, path, 0, 1); + BUG_ON(ret < 0); + path->lowest_level = 0; + btrfs_release_path(root, path); + return 0; + } - if (level == 0) - btrfs_item_key_to_cpu(eb, &found_key, 0); - else - btrfs_node_key_to_cpu(eb, &found_key, 0); + mutex_lock(&root->fs_info->tree_reloc_mutex); + ret = init_reloc_tree(trans, root); + BUG_ON(ret); + reloc_root = root->reloc_root; - btrfs_tree_unlock(eb); - free_extent_buffer(eb); + shared_level = ref_path->shared_level; + ref_path->shared_level = BTRFS_MAX_LEVEL - 1; - ret = find_root_for_ref(extent_root, path, &found_key, - level, 0, &found_root, - extent_key->objectid); + keys = ref_path->node_keys; + nodes = ref_path->new_nodes; + memset(&keys[shared_level + 1], 0, + sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1)); + memset(&nodes[shared_level + 1], 0, + sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1)); - if (ret) - goto out; + if (nodes[lowest_level] == 0) { + path->lowest_level = lowest_level; + ret = btrfs_search_slot(trans, reloc_root, first_key, path, + 0, 1); + BUG_ON(ret); + for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) { + eb = path->nodes[level]; + if (!eb || eb == reloc_root->node) + break; + nodes[level] = eb->start; + if (level == 0) + btrfs_item_key_to_cpu(eb, &keys[level], 0); + else + btrfs_node_key_to_cpu(eb, &keys[level], 0); + } + if (nodes[0] && + ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { + eb = path->nodes[0]; + ret = replace_extents_in_leaf(trans, reloc_root, eb, + group, reloc_inode); + BUG_ON(ret); + } + btrfs_release_path(reloc_root, path); + } else { + ret = btrfs_merge_path(trans, reloc_root, keys, nodes, + lowest_level); + BUG_ON(ret); + } - /* - * right here almost anything could happen to our key, - * but that's ok. The cow below will either relocate it - * or someone else will have relocated it. Either way, - * it is in a different spot than it was before and - * we're happy. - */ + /* + * replace tree blocks in the fs tree with tree blocks in + * the reloc tree. + */ + ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level); + BUG_ON(ret < 0); - trans = btrfs_start_transaction(found_root, 1); + if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { + ret = btrfs_search_slot(trans, reloc_root, first_key, path, + 0, 0); + BUG_ON(ret); + extent_buffer_get(path->nodes[0]); + eb = path->nodes[0]; + btrfs_release_path(reloc_root, path); + ret = invalidate_extent_cache(reloc_root, eb, group, root); + BUG_ON(ret); + free_extent_buffer(eb); + } - if (found_root == extent_root->fs_info->extent_root || - found_root == extent_root->fs_info->chunk_root || - found_root == extent_root->fs_info->dev_root) { - needs_lock = 1; - mutex_lock(&extent_root->fs_info->alloc_mutex); - } + mutex_unlock(&root->fs_info->tree_reloc_mutex); + path->lowest_level = 0; + return 0; +} - path->lowest_level = level; - path->reada = 2; - ret = btrfs_search_slot(trans, found_root, &found_key, path, - 0, 1); - path->lowest_level = 0; - btrfs_release_path(found_root, path); +static noinline int relocate_tree_block(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_key *first_key, + struct btrfs_ref_path *ref_path) +{ + int ret; - if (found_root == found_root->fs_info->extent_root) - btrfs_extent_post_op(trans, found_root); - if (needs_lock) - mutex_unlock(&extent_root->fs_info->alloc_mutex); + ret = relocate_one_path(trans, root, path, first_key, + ref_path, NULL, NULL); + BUG_ON(ret); - btrfs_end_transaction(trans, found_root); + if (root == root->fs_info->extent_root) + btrfs_extent_post_op(trans, root); - } -out: - mutex_lock(&extent_root->fs_info->alloc_mutex); return 0; } -static int noinline del_extent_zero(struct btrfs_root *extent_root, +static noinline int del_extent_zero(struct btrfs_trans_handle *trans, + struct btrfs_root *extent_root, struct btrfs_path *path, struct btrfs_key *extent_key) -{ - int ret; - struct btrfs_trans_handle *trans; - - trans = btrfs_start_transaction(extent_root, 1); - ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1); - if (ret > 0) { - ret = -EIO; - goto out; - } - if (ret < 0) +{ + int ret; + + ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1); + if (ret) goto out; ret = btrfs_del_item(trans, extent_root, path); out: - btrfs_end_transaction(trans, extent_root); + btrfs_release_path(extent_root, path); return ret; } -static int noinline relocate_one_extent(struct btrfs_root *extent_root, +static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info, + struct btrfs_ref_path *ref_path) +{ + struct btrfs_key root_key; + + root_key.objectid = ref_path->root_objectid; + root_key.type = BTRFS_ROOT_ITEM_KEY; + if (is_cowonly_root(ref_path->root_objectid)) + root_key.offset = 0; + else + root_key.offset = (u64)-1; + + return btrfs_read_fs_root_no_name(fs_info, &root_key); +} + +static noinline int relocate_one_extent(struct btrfs_root *extent_root, struct btrfs_path *path, - struct btrfs_key *extent_key) + struct btrfs_key *extent_key, + struct btrfs_block_group_cache *group, + struct inode *reloc_inode, int pass) { - struct btrfs_key key; - struct btrfs_key found_key; - struct extent_buffer *leaf; - u64 last_file_objectid = 0; - u64 last_file_root = 0; - u64 last_file_offset = (u64)-1; - u64 last_extent = 0; - u32 nritems; - u32 item_size; - int ret = 0; + struct btrfs_trans_handle *trans; + struct btrfs_root *found_root; + struct btrfs_ref_path *ref_path = NULL; + struct disk_extent *new_extents = NULL; + int nr_extents = 0; + int loops; + int ret; + int level; + struct btrfs_key first_key; + u64 prev_block = 0; + + + trans = btrfs_start_transaction(extent_root, 1); + BUG_ON(!trans); if (extent_key->objectid == 0) { - ret = del_extent_zero(extent_root, path, extent_key); + ret = del_extent_zero(trans, extent_root, path, extent_key); goto out; } - key.objectid = extent_key->objectid; - key.type = BTRFS_EXTENT_REF_KEY; - key.offset = 0; - while(1) { - ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); + ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS); + if (!ref_path) { + ret = -ENOMEM; + goto out; + } + for (loops = 0; ; loops++) { + if (loops == 0) { + ret = btrfs_first_ref_path(trans, extent_root, ref_path, + extent_key->objectid); + } else { + ret = btrfs_next_ref_path(trans, extent_root, ref_path); + } if (ret < 0) goto out; + if (ret > 0) + break; - ret = 0; - leaf = path->nodes[0]; - nritems = btrfs_header_nritems(leaf); - if (path->slots[0] == nritems) { - ret = btrfs_next_leaf(extent_root, path); - if (ret > 0) { - ret = 0; - goto out; + if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID || + ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID) + continue; + + found_root = read_ref_root(extent_root->fs_info, ref_path); + BUG_ON(!found_root); + /* + * for reference counted tree, only process reference paths + * rooted at the latest committed root. + */ + if (found_root->ref_cows && + ref_path->root_generation != found_root->root_key.offset) + continue; + + if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { + if (pass == 0) { + /* + * copy data extents to new locations + */ + u64 group_start = group->key.objectid; + ret = relocate_data_extent(reloc_inode, + extent_key, + group_start); + if (ret < 0) + goto out; + break; } - if (ret < 0) - goto out; - leaf = path->nodes[0]; + level = 0; + } else { + level = ref_path->owner_objectid; } - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); - if (found_key.objectid != extent_key->objectid) { - break; - } + if (prev_block != ref_path->nodes[level]) { + struct extent_buffer *eb; + u64 block_start = ref_path->nodes[level]; + u64 block_size = btrfs_level_size(found_root, level); - if (found_key.type != BTRFS_EXTENT_REF_KEY) { - break; - } + eb = read_tree_block(found_root, block_start, + block_size, 0); + btrfs_tree_lock(eb); + BUG_ON(level != btrfs_header_level(eb)); - key.offset = found_key.offset + 1; - item_size = btrfs_item_size_nr(leaf, path->slots[0]); + if (level == 0) + btrfs_item_key_to_cpu(eb, &first_key, 0); + else + btrfs_node_key_to_cpu(eb, &first_key, 0); - ret = relocate_one_reference(extent_root, path, extent_key, - &last_file_objectid, - &last_file_offset, - &last_file_root, last_extent); - if (ret) + btrfs_tree_unlock(eb); + free_extent_buffer(eb); + prev_block = block_start; + } + + btrfs_record_root_in_trans(found_root); + if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) { + /* + * try to update data extent references while + * keeping metadata shared between snapshots. + */ + if (pass == 1) { + ret = relocate_one_path(trans, found_root, + path, &first_key, ref_path, + group, reloc_inode); + if (ret < 0) + goto out; + continue; + } + /* + * use fallback method to process the remaining + * references. + */ + if (!new_extents) { + u64 group_start = group->key.objectid; + new_extents = kmalloc(sizeof(*new_extents), + GFP_NOFS); + nr_extents = 1; + ret = get_new_locations(reloc_inode, + extent_key, + group_start, 1, + &new_extents, + &nr_extents); + if (ret) + goto out; + } + ret = replace_one_extent(trans, found_root, + path, extent_key, + &first_key, ref_path, + new_extents, nr_extents); + } else { + ret = relocate_tree_block(trans, found_root, path, + &first_key, ref_path); + } + if (ret < 0) goto out; - last_extent = extent_key->objectid; } ret = 0; out: - btrfs_release_path(extent_root, path); + btrfs_end_transaction(trans, extent_root); + kfree(new_extents); + kfree(ref_path); return ret; } @@ -3306,7 +5697,7 @@ static u64 update_block_group_flags(struct btrfs_root *root, u64 flags) u64 stripped = BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10; - num_devices = root->fs_info->fs_devices->num_devices; + num_devices = root->fs_info->fs_devices->rw_devices; if (num_devices == 1) { stripped |= BTRFS_BLOCK_GROUP_DUP; stripped = flags & ~stripped; @@ -3338,7 +5729,7 @@ static u64 update_block_group_flags(struct btrfs_root *root, u64 flags) return flags; } -int __alloc_chunk_for_shrink(struct btrfs_root *root, +static int __alloc_chunk_for_shrink(struct btrfs_root *root, struct btrfs_block_group_cache *shrink_block_group, int force) { @@ -3349,10 +5740,8 @@ int __alloc_chunk_for_shrink(struct btrfs_root *root, spin_lock(&shrink_block_group->lock); if (btrfs_block_group_used(&shrink_block_group->item) > 0) { spin_unlock(&shrink_block_group->lock); - mutex_unlock(&root->fs_info->alloc_mutex); trans = btrfs_start_transaction(root, 1); - mutex_lock(&root->fs_info->alloc_mutex); spin_lock(&shrink_block_group->lock); new_alloc_flags = update_block_group_flags(root, @@ -3368,93 +5757,199 @@ int __alloc_chunk_for_shrink(struct btrfs_root *root, do_chunk_alloc(trans, root->fs_info->extent_root, calc + 2 * 1024 * 1024, new_alloc_flags, force); - mutex_unlock(&root->fs_info->alloc_mutex); btrfs_end_transaction(trans, root); - mutex_lock(&root->fs_info->alloc_mutex); } else spin_unlock(&shrink_block_group->lock); return 0; } -int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start) +static int __insert_orphan_inode(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 objectid, u64 size) +{ + struct btrfs_path *path; + struct btrfs_inode_item *item; + struct extent_buffer *leaf; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = btrfs_insert_empty_inode(trans, root, path, objectid); + if (ret) + goto out; + + leaf = path->nodes[0]; + item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); + memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); + btrfs_set_inode_generation(leaf, item, 1); + btrfs_set_inode_size(leaf, item, size); + btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); + btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(root, path); +out: + btrfs_free_path(path); + return ret; +} + +static noinline struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *group) +{ + struct inode *inode = NULL; + struct btrfs_trans_handle *trans; + struct btrfs_root *root; + struct btrfs_key root_key; + u64 objectid = BTRFS_FIRST_FREE_OBJECTID; + int err = 0; + + root_key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID; + root_key.type = BTRFS_ROOT_ITEM_KEY; + root_key.offset = (u64)-1; + root = btrfs_read_fs_root_no_name(fs_info, &root_key); + if (IS_ERR(root)) + return ERR_CAST(root); + + trans = btrfs_start_transaction(root, 1); + BUG_ON(!trans); + + err = btrfs_find_free_objectid(trans, root, objectid, &objectid); + if (err) + goto out; + + err = __insert_orphan_inode(trans, root, objectid, group->key.offset); + BUG_ON(err); + + err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0, + group->key.offset, 0, group->key.offset, + 0, 0, 0); + BUG_ON(err); + + inode = btrfs_iget_locked(root->fs_info->sb, objectid, root); + if (inode->i_state & I_NEW) { + BTRFS_I(inode)->root = root; + BTRFS_I(inode)->location.objectid = objectid; + BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY; + BTRFS_I(inode)->location.offset = 0; + btrfs_read_locked_inode(inode); + unlock_new_inode(inode); + BUG_ON(is_bad_inode(inode)); + } else { + BUG_ON(1); + } + BTRFS_I(inode)->index_cnt = group->key.objectid; + + err = btrfs_orphan_add(trans, inode); +out: + btrfs_end_transaction(trans, root); + if (err) { + if (inode) + iput(inode); + inode = ERR_PTR(err); + } + return inode; +} + +int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) +{ + + struct btrfs_ordered_sum *sums; + struct btrfs_sector_sum *sector_sum; + struct btrfs_ordered_extent *ordered; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct list_head list; + size_t offset; + int ret; + u64 disk_bytenr; + + INIT_LIST_HEAD(&list); + + ordered = btrfs_lookup_ordered_extent(inode, file_pos); + BUG_ON(ordered->file_offset != file_pos || ordered->len != len); + + disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; + ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr, + disk_bytenr + len - 1, &list); + + while (!list_empty(&list)) { + sums = list_entry(list.next, struct btrfs_ordered_sum, list); + list_del_init(&sums->list); + + sector_sum = sums->sums; + sums->bytenr = ordered->start; + + offset = 0; + while (offset < sums->len) { + sector_sum->bytenr += ordered->start - disk_bytenr; + sector_sum++; + offset += root->sectorsize; + } + + btrfs_add_ordered_sum(inode, ordered, sums); + } + btrfs_put_ordered_extent(ordered); + return 0; +} + +int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start) { struct btrfs_trans_handle *trans; - struct btrfs_root *tree_root = root->fs_info->tree_root; struct btrfs_path *path; - u64 cur_byte; - u64 total_found; - u64 shrink_last_byte; - struct btrfs_block_group_cache *shrink_block_group; struct btrfs_fs_info *info = root->fs_info; - struct btrfs_key key; - struct btrfs_key found_key; struct extent_buffer *leaf; + struct inode *reloc_inode; + struct btrfs_block_group_cache *block_group; + struct btrfs_key key; + u64 skipped; + u64 cur_byte; + u64 total_found; u32 nritems; int ret; int progress; + int pass = 0; + + root = root->fs_info->extent_root; - mutex_lock(&root->fs_info->alloc_mutex); - shrink_block_group = btrfs_lookup_block_group(root->fs_info, - shrink_start); - BUG_ON(!shrink_block_group); + block_group = btrfs_lookup_block_group(info, group_start); + BUG_ON(!block_group); - shrink_last_byte = shrink_block_group->key.objectid + - shrink_block_group->key.offset; + printk(KERN_INFO "btrfs relocating block group %llu flags %llu\n", + (unsigned long long)block_group->key.objectid, + (unsigned long long)block_group->flags); - shrink_block_group->space_info->total_bytes -= - shrink_block_group->key.offset; path = btrfs_alloc_path(); - root = root->fs_info->extent_root; - path->reada = 2; + BUG_ON(!path); - printk("btrfs relocating block group %llu flags %llu\n", - (unsigned long long)shrink_start, - (unsigned long long)shrink_block_group->flags); + reloc_inode = create_reloc_inode(info, block_group); + BUG_ON(IS_ERR(reloc_inode)); - __alloc_chunk_for_shrink(root, shrink_block_group, 1); + __alloc_chunk_for_shrink(root, block_group, 1); + set_block_group_readonly(block_group); + btrfs_start_delalloc_inodes(info->tree_root); + btrfs_wait_ordered_extents(info->tree_root, 0); again: - - shrink_block_group->ro = 1; - + skipped = 0; total_found = 0; progress = 0; - key.objectid = shrink_start; + key.objectid = block_group->key.objectid; key.offset = 0; key.type = 0; cur_byte = key.objectid; - mutex_unlock(&root->fs_info->alloc_mutex); - - btrfs_start_delalloc_inodes(root); - btrfs_wait_ordered_extents(tree_root, 0); - - mutex_lock(&root->fs_info->alloc_mutex); - - ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); - if (ret < 0) - goto out; - - ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY); - if (ret < 0) - goto out; + trans = btrfs_start_transaction(info->tree_root, 1); + btrfs_commit_transaction(trans, info->tree_root); - if (ret == 0) { - leaf = path->nodes[0]; - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); - if (found_key.objectid + found_key.offset > shrink_start && - found_key.objectid < shrink_last_byte) { - cur_byte = found_key.objectid; - key.objectid = cur_byte; - } - } - btrfs_release_path(root, path); + mutex_lock(&root->fs_info->cleaner_mutex); + btrfs_clean_old_snapshots(info->tree_root); + btrfs_remove_leaf_refs(info->tree_root, (u64)-1, 1); + mutex_unlock(&root->fs_info->cleaner_mutex); - while(1) { + while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; - next: leaf = path->nodes[0]; nritems = btrfs_header_nritems(leaf); @@ -3470,112 +5965,82 @@ next: nritems = btrfs_header_nritems(leaf); } - btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); - if (found_key.objectid >= shrink_last_byte) + if (key.objectid >= block_group->key.objectid + + block_group->key.offset) break; if (progress && need_resched()) { - memcpy(&key, &found_key, sizeof(key)); - cond_resched(); btrfs_release_path(root, path); - btrfs_search_slot(NULL, root, &key, path, 0, 0); + cond_resched(); progress = 0; - goto next; + continue; } progress = 1; - if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY || - found_key.objectid + found_key.offset <= cur_byte) { - memcpy(&key, &found_key, sizeof(key)); - key.offset++; + if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY || + key.objectid + key.offset <= cur_byte) { path->slots[0]++; goto next; } total_found++; - cur_byte = found_key.objectid + found_key.offset; - key.objectid = cur_byte; + cur_byte = key.objectid + key.offset; btrfs_release_path(root, path); - ret = relocate_one_extent(root, path, &found_key); - __alloc_chunk_for_shrink(root, shrink_block_group, 0); - } - - btrfs_release_path(root, path); - - if (total_found > 0) { - printk("btrfs relocate found %llu last extent was %llu\n", - (unsigned long long)total_found, - (unsigned long long)found_key.objectid); - mutex_unlock(&root->fs_info->alloc_mutex); - trans = btrfs_start_transaction(tree_root, 1); - btrfs_commit_transaction(trans, tree_root); - btrfs_clean_old_snapshots(tree_root); + __alloc_chunk_for_shrink(root, block_group, 0); + ret = relocate_one_extent(root, path, &key, block_group, + reloc_inode, pass); + BUG_ON(ret < 0); + if (ret > 0) + skipped++; - btrfs_start_delalloc_inodes(root); - btrfs_wait_ordered_extents(tree_root, 0); - - trans = btrfs_start_transaction(tree_root, 1); - btrfs_commit_transaction(trans, tree_root); - mutex_lock(&root->fs_info->alloc_mutex); - goto again; + key.objectid = cur_byte; + key.type = 0; + key.offset = 0; } - /* - * we've freed all the extents, now remove the block - * group item from the tree - */ - mutex_unlock(&root->fs_info->alloc_mutex); - - trans = btrfs_start_transaction(root, 1); - - mutex_lock(&root->fs_info->alloc_mutex); - memcpy(&key, &shrink_block_group->key, sizeof(key)); + btrfs_release_path(root, path); - ret = btrfs_search_slot(trans, root, &key, path, -1, 1); - if (ret > 0) - ret = -EIO; - if (ret < 0) { - btrfs_end_transaction(trans, root); - goto out; + if (pass == 0) { + btrfs_wait_ordered_range(reloc_inode, 0, (u64)-1); + invalidate_mapping_pages(reloc_inode->i_mapping, 0, -1); } - clear_extent_bits(&info->block_group_cache, key.objectid, - key.objectid + key.offset - 1, - (unsigned int)-1, GFP_NOFS); - - - clear_extent_bits(&info->free_space_cache, - key.objectid, key.objectid + key.offset - 1, - (unsigned int)-1, GFP_NOFS); - - /* - memset(shrink_block_group, 0, sizeof(*shrink_block_group)); - kfree(shrink_block_group); - */ + if (total_found > 0) { + printk(KERN_INFO "btrfs found %llu extents in pass %d\n", + (unsigned long long)total_found, pass); + pass++; + if (total_found == skipped && pass > 2) { + iput(reloc_inode); + reloc_inode = create_reloc_inode(info, block_group); + pass = 0; + } + goto again; + } - btrfs_del_item(trans, root, path); - btrfs_release_path(root, path); - mutex_unlock(&root->fs_info->alloc_mutex); - btrfs_commit_transaction(trans, root); + /* delete reloc_inode */ + iput(reloc_inode); - mutex_lock(&root->fs_info->alloc_mutex); + /* unpin extents in this range */ + trans = btrfs_start_transaction(info->tree_root, 1); + btrfs_commit_transaction(trans, info->tree_root); - /* the code to unpin extents might set a few bits in the free - * space cache for this range again - */ - clear_extent_bits(&info->free_space_cache, - key.objectid, key.objectid + key.offset - 1, - (unsigned int)-1, GFP_NOFS); + spin_lock(&block_group->lock); + WARN_ON(block_group->pinned > 0); + WARN_ON(block_group->reserved > 0); + WARN_ON(btrfs_block_group_used(&block_group->item) > 0); + spin_unlock(&block_group->lock); + put_block_group(block_group); + ret = 0; out: btrfs_free_path(path); - mutex_unlock(&root->fs_info->alloc_mutex); return ret; } -int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path, - struct btrfs_key *key) +static int find_first_block_group(struct btrfs_root *root, + struct btrfs_path *path, struct btrfs_key *key) { int ret = 0; struct btrfs_key found_key; @@ -3586,7 +6051,7 @@ int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path, if (ret < 0) goto out; - while(1) { + while (1) { slot = path->slots[0]; leaf = path->nodes[0]; if (slot >= btrfs_header_nritems(leaf)) { @@ -3611,20 +6076,44 @@ out: return ret; } +int btrfs_free_block_groups(struct btrfs_fs_info *info) +{ + struct btrfs_block_group_cache *block_group; + struct rb_node *n; + + spin_lock(&info->block_group_cache_lock); + while ((n = rb_last(&info->block_group_cache_tree)) != NULL) { + block_group = rb_entry(n, struct btrfs_block_group_cache, + cache_node); + rb_erase(&block_group->cache_node, + &info->block_group_cache_tree); + spin_unlock(&info->block_group_cache_lock); + + btrfs_remove_free_space_cache(block_group); + down_write(&block_group->space_info->groups_sem); + list_del(&block_group->list); + up_write(&block_group->space_info->groups_sem); + + WARN_ON(atomic_read(&block_group->count) != 1); + kfree(block_group); + + spin_lock(&info->block_group_cache_lock); + } + spin_unlock(&info->block_group_cache_lock); + return 0; +} + int btrfs_read_block_groups(struct btrfs_root *root) { struct btrfs_path *path; int ret; - int bit; struct btrfs_block_group_cache *cache; struct btrfs_fs_info *info = root->fs_info; struct btrfs_space_info *space_info; - struct extent_io_tree *block_group_cache; struct btrfs_key key; struct btrfs_key found_key; struct extent_buffer *leaf; - block_group_cache = &info->block_group_cache; root = info->extent_root; key.objectid = 0; key.offset = 0; @@ -3633,8 +6122,7 @@ int btrfs_read_block_groups(struct btrfs_root *root) if (!path) return -ENOMEM; - mutex_lock(&root->fs_info->alloc_mutex); - while(1) { + while (1) { ret = find_first_block_group(root, path, &key); if (ret > 0) { ret = 0; @@ -3651,7 +6139,11 @@ int btrfs_read_block_groups(struct btrfs_root *root) break; } + atomic_set(&cache->count, 1); spin_lock_init(&cache->lock); + mutex_init(&cache->alloc_mutex); + mutex_init(&cache->cache_mutex); + INIT_LIST_HEAD(&cache->list); read_extent_buffer(leaf, &cache->item, btrfs_item_ptr_offset(leaf, path->slots[0]), sizeof(cache->item)); @@ -3660,39 +6152,26 @@ int btrfs_read_block_groups(struct btrfs_root *root) key.objectid = found_key.objectid + found_key.offset; btrfs_release_path(root, path); cache->flags = btrfs_block_group_flags(&cache->item); - bit = 0; - if (cache->flags & BTRFS_BLOCK_GROUP_DATA) { - bit = BLOCK_GROUP_DATA; - } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) { - bit = BLOCK_GROUP_SYSTEM; - } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) { - bit = BLOCK_GROUP_METADATA; - } - set_avail_alloc_bits(info, cache->flags); ret = update_space_info(info, cache->flags, found_key.offset, btrfs_block_group_used(&cache->item), &space_info); BUG_ON(ret); cache->space_info = space_info; + down_write(&space_info->groups_sem); + list_add_tail(&cache->list, &space_info->block_groups); + up_write(&space_info->groups_sem); - /* use EXTENT_LOCKED to prevent merging */ - set_extent_bits(block_group_cache, found_key.objectid, - found_key.objectid + found_key.offset - 1, - EXTENT_LOCKED, GFP_NOFS); - set_state_private(block_group_cache, found_key.objectid, - (unsigned long)cache); - set_extent_bits(block_group_cache, found_key.objectid, - found_key.objectid + found_key.offset - 1, - bit | EXTENT_LOCKED, GFP_NOFS); - if (key.objectid >= - btrfs_super_total_bytes(&info->super_copy)) - break; + ret = btrfs_add_block_group_cache(root->fs_info, cache); + BUG_ON(ret); + + set_avail_alloc_bits(root->fs_info, cache->flags); + if (btrfs_chunk_readonly(root, cache->key.objectid)) + set_block_group_readonly(cache); } ret = 0; error: btrfs_free_path(path); - mutex_unlock(&root->fs_info->alloc_mutex); return ret; } @@ -3702,23 +6181,25 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, u64 size) { int ret; - int bit = 0; struct btrfs_root *extent_root; struct btrfs_block_group_cache *cache; - struct extent_io_tree *block_group_cache; - WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex)); extent_root = root->fs_info->extent_root; - block_group_cache = &root->fs_info->block_group_cache; root->fs_info->last_trans_new_blockgroup = trans->transid; cache = kzalloc(sizeof(*cache), GFP_NOFS); - BUG_ON(!cache); + if (!cache) + return -ENOMEM; + cache->key.objectid = chunk_offset; cache->key.offset = size; + cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; + atomic_set(&cache->count, 1); spin_lock_init(&cache->lock); - btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY); + mutex_init(&cache->alloc_mutex); + mutex_init(&cache->cache_mutex); + INIT_LIST_HEAD(&cache->list); btrfs_set_block_group_used(&cache->item, bytes_used); btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid); @@ -3728,25 +6209,70 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, ret = update_space_info(root->fs_info, cache->flags, size, bytes_used, &cache->space_info); BUG_ON(ret); + down_write(&cache->space_info->groups_sem); + list_add_tail(&cache->list, &cache->space_info->block_groups); + up_write(&cache->space_info->groups_sem); - bit = block_group_state_bits(type); - set_extent_bits(block_group_cache, chunk_offset, - chunk_offset + size - 1, - EXTENT_LOCKED, GFP_NOFS); - set_state_private(block_group_cache, chunk_offset, - (unsigned long)cache); - set_extent_bits(block_group_cache, chunk_offset, - chunk_offset + size - 1, - bit | EXTENT_LOCKED, GFP_NOFS); + ret = btrfs_add_block_group_cache(root->fs_info, cache); + BUG_ON(ret); ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item, sizeof(cache->item)); BUG_ON(ret); - finish_current_insert(trans, extent_root); - ret = del_pending_extents(trans, extent_root); + finish_current_insert(trans, extent_root, 0); + ret = del_pending_extents(trans, extent_root, 0); BUG_ON(ret); set_avail_alloc_bits(extent_root->fs_info, type); return 0; } + +int btrfs_remove_block_group(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 group_start) +{ + struct btrfs_path *path; + struct btrfs_block_group_cache *block_group; + struct btrfs_key key; + int ret; + + root = root->fs_info->extent_root; + + block_group = btrfs_lookup_block_group(root->fs_info, group_start); + BUG_ON(!block_group); + BUG_ON(!block_group->ro); + + memcpy(&key, &block_group->key, sizeof(key)); + + path = btrfs_alloc_path(); + BUG_ON(!path); + + spin_lock(&root->fs_info->block_group_cache_lock); + rb_erase(&block_group->cache_node, + &root->fs_info->block_group_cache_tree); + spin_unlock(&root->fs_info->block_group_cache_lock); + btrfs_remove_free_space_cache(block_group); + down_write(&block_group->space_info->groups_sem); + list_del(&block_group->list); + up_write(&block_group->space_info->groups_sem); + + spin_lock(&block_group->space_info->lock); + block_group->space_info->total_bytes -= block_group->key.offset; + block_group->space_info->bytes_readonly -= block_group->key.offset; + spin_unlock(&block_group->space_info->lock); + block_group->space_info->full = 0; + + put_block_group(block_group); + put_block_group(block_group); + + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + if (ret > 0) + ret = -EIO; + if (ret < 0) + goto out; + + ret = btrfs_del_item(trans, root, path); +out: + btrfs_free_path(path); + return ret; +}