X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Focfs2%2Fextent_map.c;h=c58668a326fe87f58074741965c531761fe97359;hb=0fe1c1371342869f4693ad42929c1388842b0f3e;hp=3b4322fd369ae8aea8506034b25e0c66adbbee1a;hpb=363041a5f74b953ab6b705ac9c88e5eda218a24b;p=linux-2.6-omap-h63xx.git diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c index 3b4322fd369..c58668a326f 100644 --- a/fs/ocfs2/extent_map.c +++ b/fs/ocfs2/extent_map.c @@ -39,38 +39,346 @@ #include "buffer_head_io.h" /* - * Return the index of the extent record which contains cluster #v_cluster. - * -1 is returned if it was not found. + * The extent caching implementation is intentionally trivial. * - * Should work fine on interior and exterior nodes. + * We only cache a small number of extents stored directly on the + * inode, so linear order operations are acceptable. If we ever want + * to increase the size of the extent map, then these algorithms must + * get smarter. */ -static int ocfs2_search_extent_list(struct ocfs2_extent_list *el, - u32 v_cluster) + +void ocfs2_extent_map_init(struct inode *inode) +{ + struct ocfs2_inode_info *oi = OCFS2_I(inode); + + oi->ip_extent_map.em_num_items = 0; + INIT_LIST_HEAD(&oi->ip_extent_map.em_list); +} + +static void __ocfs2_extent_map_lookup(struct ocfs2_extent_map *em, + unsigned int cpos, + struct ocfs2_extent_map_item **ret_emi) +{ + unsigned int range; + struct ocfs2_extent_map_item *emi; + + *ret_emi = NULL; + + list_for_each_entry(emi, &em->em_list, ei_list) { + range = emi->ei_cpos + emi->ei_clusters; + + if (cpos >= emi->ei_cpos && cpos < range) { + list_move(&emi->ei_list, &em->em_list); + + *ret_emi = emi; + break; + } + } +} + +static int ocfs2_extent_map_lookup(struct inode *inode, unsigned int cpos, + unsigned int *phys, unsigned int *len, + unsigned int *flags) +{ + unsigned int coff; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_extent_map_item *emi; + + spin_lock(&oi->ip_lock); + + __ocfs2_extent_map_lookup(&oi->ip_extent_map, cpos, &emi); + if (emi) { + coff = cpos - emi->ei_cpos; + *phys = emi->ei_phys + coff; + if (len) + *len = emi->ei_clusters - coff; + if (flags) + *flags = emi->ei_flags; + } + + spin_unlock(&oi->ip_lock); + + if (emi == NULL) + return -ENOENT; + + return 0; +} + +/* + * Forget about all clusters equal to or greater than cpos. + */ +void ocfs2_extent_map_trunc(struct inode *inode, unsigned int cpos) +{ + struct ocfs2_extent_map_item *emi, *n; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_extent_map *em = &oi->ip_extent_map; + LIST_HEAD(tmp_list); + unsigned int range; + + spin_lock(&oi->ip_lock); + list_for_each_entry_safe(emi, n, &em->em_list, ei_list) { + if (emi->ei_cpos >= cpos) { + /* Full truncate of this record. */ + list_move(&emi->ei_list, &tmp_list); + BUG_ON(em->em_num_items == 0); + em->em_num_items--; + continue; + } + + range = emi->ei_cpos + emi->ei_clusters; + if (range > cpos) { + /* Partial truncate */ + emi->ei_clusters = cpos - emi->ei_cpos; + } + } + spin_unlock(&oi->ip_lock); + + list_for_each_entry_safe(emi, n, &tmp_list, ei_list) { + list_del(&emi->ei_list); + kfree(emi); + } +} + +/* + * Is any part of emi2 contained within emi1 + */ +static int ocfs2_ei_is_contained(struct ocfs2_extent_map_item *emi1, + struct ocfs2_extent_map_item *emi2) +{ + unsigned int range1, range2; + + /* + * Check if logical start of emi2 is inside emi1 + */ + range1 = emi1->ei_cpos + emi1->ei_clusters; + if (emi2->ei_cpos >= emi1->ei_cpos && emi2->ei_cpos < range1) + return 1; + + /* + * Check if logical end of emi2 is inside emi1 + */ + range2 = emi2->ei_cpos + emi2->ei_clusters; + if (range2 > emi1->ei_cpos && range2 <= range1) + return 1; + + return 0; +} + +static void ocfs2_copy_emi_fields(struct ocfs2_extent_map_item *dest, + struct ocfs2_extent_map_item *src) +{ + dest->ei_cpos = src->ei_cpos; + dest->ei_phys = src->ei_phys; + dest->ei_clusters = src->ei_clusters; + dest->ei_flags = src->ei_flags; +} + +/* + * Try to merge emi with ins. Returns 1 if merge succeeds, zero + * otherwise. + */ +static int ocfs2_try_to_merge_extent_map(struct ocfs2_extent_map_item *emi, + struct ocfs2_extent_map_item *ins) +{ + /* + * Handle contiguousness + */ + if (ins->ei_phys == (emi->ei_phys + emi->ei_clusters) && + ins->ei_cpos == (emi->ei_cpos + emi->ei_clusters) && + ins->ei_flags == emi->ei_flags) { + emi->ei_clusters += ins->ei_clusters; + return 1; + } else if ((ins->ei_phys + ins->ei_clusters) == emi->ei_phys && + (ins->ei_cpos + ins->ei_clusters) == emi->ei_phys && + ins->ei_flags == emi->ei_flags) { + emi->ei_phys = ins->ei_phys; + emi->ei_cpos = ins->ei_cpos; + emi->ei_clusters += ins->ei_clusters; + return 1; + } + + /* + * Overlapping extents - this shouldn't happen unless we've + * split an extent to change it's flags. That is exceedingly + * rare, so there's no sense in trying to optimize it yet. + */ + if (ocfs2_ei_is_contained(emi, ins) || + ocfs2_ei_is_contained(ins, emi)) { + ocfs2_copy_emi_fields(emi, ins); + return 1; + } + + /* No merge was possible. */ + return 0; +} + +/* + * In order to reduce complexity on the caller, this insert function + * is intentionally liberal in what it will accept. + * + * The only rule is that the truncate call *must* be used whenever + * records have been deleted. This avoids inserting overlapping + * records with different physical mappings. + */ +void ocfs2_extent_map_insert_rec(struct inode *inode, + struct ocfs2_extent_rec *rec) +{ + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_extent_map *em = &oi->ip_extent_map; + struct ocfs2_extent_map_item *emi, *new_emi = NULL; + struct ocfs2_extent_map_item ins; + + ins.ei_cpos = le32_to_cpu(rec->e_cpos); + ins.ei_phys = ocfs2_blocks_to_clusters(inode->i_sb, + le64_to_cpu(rec->e_blkno)); + ins.ei_clusters = le16_to_cpu(rec->e_leaf_clusters); + ins.ei_flags = rec->e_flags; + +search: + spin_lock(&oi->ip_lock); + + list_for_each_entry(emi, &em->em_list, ei_list) { + if (ocfs2_try_to_merge_extent_map(emi, &ins)) { + list_move(&emi->ei_list, &em->em_list); + spin_unlock(&oi->ip_lock); + goto out; + } + } + + /* + * No item could be merged. + * + * Either allocate and add a new item, or overwrite the last recently + * inserted. + */ + + if (em->em_num_items < OCFS2_MAX_EXTENT_MAP_ITEMS) { + if (new_emi == NULL) { + spin_unlock(&oi->ip_lock); + + new_emi = kmalloc(sizeof(*new_emi), GFP_NOFS); + if (new_emi == NULL) + goto out; + + goto search; + } + + ocfs2_copy_emi_fields(new_emi, &ins); + list_add(&new_emi->ei_list, &em->em_list); + em->em_num_items++; + new_emi = NULL; + } else { + BUG_ON(list_empty(&em->em_list) || em->em_num_items == 0); + emi = list_entry(em->em_list.prev, + struct ocfs2_extent_map_item, ei_list); + list_move(&emi->ei_list, &em->em_list); + ocfs2_copy_emi_fields(emi, &ins); + } + + spin_unlock(&oi->ip_lock); + +out: + if (new_emi) + kfree(new_emi); +} + +/* + * Return the 1st index within el which contains an extent start + * larger than v_cluster. + */ +static int ocfs2_search_for_hole_index(struct ocfs2_extent_list *el, + u32 v_cluster) { - int ret = -1; int i; struct ocfs2_extent_rec *rec; - u32 rec_end, rec_start; for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) { rec = &el->l_recs[i]; - rec_start = le32_to_cpu(rec->e_cpos); - rec_end = rec_start + le32_to_cpu(rec->e_clusters); - - if (v_cluster >= rec_start && v_cluster < rec_end) { - ret = i; + if (v_cluster < le32_to_cpu(rec->e_cpos)) break; + } + + return i; +} + +/* + * Figure out the size of a hole which starts at v_cluster within the given + * extent list. + * + * If there is no more allocation past v_cluster, we return the maximum + * cluster size minus v_cluster. + * + * If we have in-inode extents, then el points to the dinode list and + * eb_bh is NULL. Otherwise, eb_bh should point to the extent block + * containing el. + */ +static int ocfs2_figure_hole_clusters(struct inode *inode, + struct ocfs2_extent_list *el, + struct buffer_head *eb_bh, + u32 v_cluster, + u32 *num_clusters) +{ + int ret, i; + struct buffer_head *next_eb_bh = NULL; + struct ocfs2_extent_block *eb, *next_eb; + + i = ocfs2_search_for_hole_index(el, v_cluster); + + if (i == le16_to_cpu(el->l_next_free_rec) && eb_bh) { + eb = (struct ocfs2_extent_block *)eb_bh->b_data; + + /* + * Check the next leaf for any extents. + */ + + if (le64_to_cpu(eb->h_next_leaf_blk) == 0ULL) + goto no_more_extents; + + ret = ocfs2_read_block(OCFS2_SB(inode->i_sb), + le64_to_cpu(eb->h_next_leaf_blk), + &next_eb_bh, OCFS2_BH_CACHED, inode); + if (ret) { + mlog_errno(ret); + goto out; } + next_eb = (struct ocfs2_extent_block *)next_eb_bh->b_data; + + if (!OCFS2_IS_VALID_EXTENT_BLOCK(next_eb)) { + ret = -EROFS; + OCFS2_RO_ON_INVALID_EXTENT_BLOCK(inode->i_sb, next_eb); + goto out; + } + + el = &next_eb->h_list; + + i = ocfs2_search_for_hole_index(el, v_cluster); + } + +no_more_extents: + if (i == le16_to_cpu(el->l_next_free_rec)) { + /* + * We're at the end of our existing allocation. Just + * return the maximum number of clusters we could + * possibly allocate. + */ + *num_clusters = UINT_MAX - v_cluster; + } else { + *num_clusters = le32_to_cpu(el->l_recs[i].e_cpos) - v_cluster; } + ret = 0; +out: + brelse(next_eb_bh); return ret; } -static int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, - u32 *p_cluster, u32 *num_clusters) +int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, + u32 *p_cluster, u32 *num_clusters, + unsigned int *extent_flags) { int ret, i; + unsigned int flags = 0; struct buffer_head *di_bh = NULL; struct buffer_head *eb_bh = NULL; struct ocfs2_dinode *di; @@ -79,6 +387,17 @@ static int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, struct ocfs2_extent_rec *rec; u32 coff; + if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) { + ret = -ERANGE; + mlog_errno(ret); + goto out; + } + + ret = ocfs2_extent_map_lookup(inode, v_cluster, p_cluster, + num_clusters, extent_flags); + if (ret == 0) + goto out; + ret = ocfs2_read_block(OCFS2_SB(inode->i_sb), OCFS2_I(inode)->ip_blkno, &di_bh, OCFS2_BH_CACHED, inode); if (ret) { @@ -98,17 +417,34 @@ static int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, eb = (struct ocfs2_extent_block *) eb_bh->b_data; el = &eb->h_list; + + if (el->l_tree_depth) { + ocfs2_error(inode->i_sb, + "Inode %lu has non zero tree depth in " + "leaf block %llu\n", inode->i_ino, + (unsigned long long)eb_bh->b_blocknr); + ret = -EROFS; + goto out; + } } i = ocfs2_search_extent_list(el, v_cluster); if (i == -1) { /* * A hole was found. Return some canned values that - * callers can key on. + * callers can key on. If asked for, num_clusters will + * be populated with the size of the hole. */ *p_cluster = 0; - if (num_clusters) - *num_clusters = 1; + if (num_clusters) { + ret = ocfs2_figure_hole_clusters(inode, el, eb_bh, + v_cluster, + num_clusters); + if (ret) { + mlog_errno(ret); + goto out; + } + } } else { rec = &el->l_recs[i]; @@ -118,7 +454,7 @@ static int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, ocfs2_error(inode->i_sb, "Inode %lu has bad extent " "record (%u, %u, 0)", inode->i_ino, le32_to_cpu(rec->e_cpos), - le32_to_cpu(rec->e_clusters)); + ocfs2_rec_clusters(el, rec)); ret = -EROFS; goto out; } @@ -130,9 +466,16 @@ static int ocfs2_get_clusters(struct inode *inode, u32 v_cluster, *p_cluster = *p_cluster + coff; if (num_clusters) - *num_clusters = le32_to_cpu(rec->e_clusters) - coff; + *num_clusters = ocfs2_rec_clusters(el, rec) - coff; + + flags = rec->e_flags; + + ocfs2_extent_map_insert_rec(inode, rec); } + if (extent_flags) + *extent_flags = flags; + out: brelse(di_bh); brelse(eb_bh); @@ -144,7 +487,7 @@ out: * all while the map is in the process of being updated. */ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno, - int *ret_count) + u64 *ret_count, unsigned int *extent_flags) { int ret; int bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1); @@ -153,7 +496,8 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno, cpos = ocfs2_blocks_to_clusters(inode->i_sb, v_blkno); - ret = ocfs2_get_clusters(inode, cpos, &p_cluster, &num_clusters); + ret = ocfs2_get_clusters(inode, cpos, &p_cluster, &num_clusters, + extent_flags); if (ret) { mlog_errno(ret); goto out;