#include "acl.h"
#include "ext4_extents.h"
+#define MPAGE_DA_EXTENT_TAIL 0x01
+
static inline int ext4_begin_ordered_truncate(struct inode *inode,
loff_t new_size)
{
unsigned long first_page, next_page; /* extent of pages */
get_block_t *get_block;
struct writeback_control *wbc;
+ int io_done;
+ long pages_written;
};
/*
* mpage_da_submit_io - walks through extent of pages and try to write
- * them with __mpage_writepage()
+ * them with writepage() call back
*
* @mpd->inode: inode
* @mpd->first_page: first page of the extent
static int mpage_da_submit_io(struct mpage_da_data *mpd)
{
struct address_space *mapping = mpd->inode->i_mapping;
- struct mpage_data mpd_pp = {
- .bio = NULL,
- .last_block_in_bio = 0,
- .get_block = mpd->get_block,
- .use_writepage = 1,
- };
int ret = 0, err, nr_pages, i;
unsigned long index, end;
struct pagevec pvec;
BUG_ON(mpd->next_page <= mpd->first_page);
-
pagevec_init(&pvec, 0);
index = mpd->first_page;
end = mpd->next_page - 1;
break;
index++;
- err = __mpage_writepage(page, mpd->wbc, &mpd_pp);
-
+ err = mapping->a_ops->writepage(page, mpd->wbc);
+ if (!err)
+ mpd->pages_written++;
/*
* In error case, we have to continue because
* remaining pages are still locked
}
pagevec_release(&pvec);
}
- if (mpd_pp.bio)
- mpage_bio_submit(WRITE, mpd_pp.bio);
-
return ret;
}
int blocks = exbh->b_size >> inode->i_blkbits;
sector_t pblock = exbh->b_blocknr, cur_logical;
struct buffer_head *head, *bh;
- unsigned long index, end;
+ pgoff_t index, end;
struct pagevec pvec;
int nr_pages, i;
*
* The function skips space we know is already mapped to disk blocks.
*
- * The function ignores errors ->get_block() returns, thus real
- * error handling is postponed to __mpage_writepage()
*/
static void mpage_da_map_blocks(struct mpage_da_data *mpd)
{
+ int err = 0;
struct buffer_head *lbh = &mpd->lbh;
- int err = 0, remain = lbh->b_size;
sector_t next = lbh->b_blocknr;
struct buffer_head new;
if (buffer_mapped(lbh) && !buffer_delay(lbh))
return;
- while (remain) {
- new.b_state = lbh->b_state;
- new.b_blocknr = 0;
- new.b_size = remain;
- err = mpd->get_block(mpd->inode, next, &new, 1);
- if (err) {
- /*
- * Rather than implement own error handling
- * here, we just leave remaining blocks
- * unallocated and try again with ->writepage()
- */
- break;
- }
- BUG_ON(new.b_size == 0);
+ new.b_state = lbh->b_state;
+ new.b_blocknr = 0;
+ new.b_size = lbh->b_size;
- if (buffer_new(&new))
- __unmap_underlying_blocks(mpd->inode, &new);
+ /*
+ * If we didn't accumulate anything
+ * to write simply return
+ */
+ if (!new.b_size)
+ return;
+ err = mpd->get_block(mpd->inode, next, &new, 1);
+ if (err)
+ return;
+ BUG_ON(new.b_size == 0);
- /*
- * If blocks are delayed marked, we need to
- * put actual blocknr and drop delayed bit
- */
- if (buffer_delay(lbh) || buffer_unwritten(lbh))
- mpage_put_bnr_to_bhs(mpd, next, &new);
+ if (buffer_new(&new))
+ __unmap_underlying_blocks(mpd->inode, &new);
- /* go for the remaining blocks */
- next += new.b_size >> mpd->inode->i_blkbits;
- remain -= new.b_size;
- }
+ /*
+ * If blocks are delayed marked, we need to
+ * put actual blocknr and drop delayed bit
+ */
+ if (buffer_delay(lbh) || buffer_unwritten(lbh))
+ mpage_put_bnr_to_bhs(mpd, next, &new);
+
+ return;
}
#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
sector_t logical, struct buffer_head *bh)
{
- struct buffer_head *lbh = &mpd->lbh;
sector_t next;
+ size_t b_size = bh->b_size;
+ struct buffer_head *lbh = &mpd->lbh;
+ int nrblocks = lbh->b_size >> mpd->inode->i_blkbits;
- next = lbh->b_blocknr + (lbh->b_size >> mpd->inode->i_blkbits);
-
+ /* check if thereserved journal credits might overflow */
+ if (!(EXT4_I(mpd->inode)->i_flags & EXT4_EXTENTS_FL)) {
+ if (nrblocks >= EXT4_MAX_TRANS_DATA) {
+ /*
+ * With non-extent format we are limited by the journal
+ * credit available. Total credit needed to insert
+ * nrblocks contiguous blocks is dependent on the
+ * nrblocks. So limit nrblocks.
+ */
+ goto flush_it;
+ } else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
+ EXT4_MAX_TRANS_DATA) {
+ /*
+ * Adding the new buffer_head would make it cross the
+ * allowed limit for which we have journal credit
+ * reserved. So limit the new bh->b_size
+ */
+ b_size = (EXT4_MAX_TRANS_DATA - nrblocks) <<
+ mpd->inode->i_blkbits;
+ /* we will do mpage_da_submit_io in the next loop */
+ }
+ }
/*
* First block in the extent
*/
if (lbh->b_size == 0) {
lbh->b_blocknr = logical;
- lbh->b_size = bh->b_size;
+ lbh->b_size = b_size;
lbh->b_state = bh->b_state & BH_FLAGS;
return;
}
+ next = lbh->b_blocknr + nrblocks;
/*
* Can we merge the block to our big extent?
*/
if (logical == next && (bh->b_state & BH_FLAGS) == lbh->b_state) {
- lbh->b_size += bh->b_size;
+ lbh->b_size += b_size;
return;
}
+flush_it:
/*
* We couldn't merge the block to our extent, so we
* need to flush current extent and start new one
*/
mpage_da_map_blocks(mpd);
-
- /*
- * Now start a new extent
- */
- lbh->b_size = bh->b_size;
- lbh->b_state = bh->b_state & BH_FLAGS;
- lbh->b_blocknr = logical;
+ mpage_da_submit_io(mpd);
+ mpd->io_done = 1;
+ return;
}
/*
struct buffer_head *bh, *head, fake;
sector_t logical;
+ if (mpd->io_done) {
+ /*
+ * Rest of the page in the page_vec
+ * redirty then and skip then. We will
+ * try to to write them again after
+ * starting a new transaction
+ */
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return MPAGE_DA_EXTENT_TAIL;
+ }
/*
* Can we merge this page to current extent?
*/
if (mpd->next_page != page->index) {
/*
* Nope, we can't. So, we map non-allocated blocks
- * and start IO on them using __mpage_writepage()
+ * and start IO on them using writepage()
*/
if (mpd->next_page != mpd->first_page) {
mpage_da_map_blocks(mpd);
mpage_da_submit_io(mpd);
+ /*
+ * skip rest of the page in the page_vec
+ */
+ mpd->io_done = 1;
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return MPAGE_DA_EXTENT_TAIL;
}
/*
set_buffer_dirty(bh);
set_buffer_uptodate(bh);
mpage_add_bh_to_extent(mpd, logical, bh);
+ if (mpd->io_done)
+ return MPAGE_DA_EXTENT_TAIL;
} else {
/*
* Page with regular buffer heads, just add all dirty ones
bh = head;
do {
BUG_ON(buffer_locked(bh));
- if (buffer_dirty(bh))
+ if (buffer_dirty(bh) &&
+ (!buffer_mapped(bh) || buffer_delay(bh))) {
mpage_add_bh_to_extent(mpd, logical, bh);
+ if (mpd->io_done)
+ return MPAGE_DA_EXTENT_TAIL;
+ }
logical++;
} while ((bh = bh->b_this_page) != head);
}
*
* This is a library function, which implements the writepages()
* address_space_operation.
- *
- * In order to avoid duplication of logic that deals with partial pages,
- * multiple bio per page, etc, we find non-allocated blocks, allocate
- * them with minimal calls to ->get_block() and re-use __mpage_writepage()
- *
- * It's important that we call __mpage_writepage() only once for each
- * involved page, otherwise we'd have to implement more complicated logic
- * to deal with pages w/o PG_lock or w/ PG_writeback and so on.
- *
- * See comments to mpage_writepages()
*/
static int mpage_da_writepages(struct address_space *mapping,
struct writeback_control *wbc,
get_block_t get_block)
{
struct mpage_da_data mpd;
+ long to_write;
int ret;
if (!get_block)
mpd.first_page = 0;
mpd.next_page = 0;
mpd.get_block = get_block;
+ mpd.io_done = 0;
+ mpd.pages_written = 0;
+
+ to_write = wbc->nr_to_write;
ret = write_cache_pages(mapping, wbc, __mpage_da_writepage, &mpd);
/*
* Handle last extent of pages
*/
- if (mpd.next_page != mpd.first_page) {
+ if (!mpd.io_done && mpd.next_page != mpd.first_page) {
mpage_da_map_blocks(&mpd);
mpage_da_submit_io(&mpd);
}
+ wbc->nr_to_write = to_write - mpd.pages_written;
return ret;
}
}
/*
- * For now just follow the DIO way to estimate the max credits
- * needed to write out EXT4_MAX_WRITEBACK_PAGES.
- * todo: need to calculate the max credits need for
- * extent based files, currently the DIO credits is based on
- * indirect-blocks mapping way.
- *
- * Probably should have a generic way to calculate credits
- * for DIO, writepages, and truncate
+ * This is called via ext4_da_writepages() to
+ * calulate the total number of credits to reserve to fit
+ * a single extent allocation into a single transaction,
+ * ext4_da_writpeages() will loop calling this before
+ * the block allocation.
*/
-#define EXT4_MAX_WRITEBACK_PAGES DIO_MAX_BLOCKS
-#define EXT4_MAX_WRITEBACK_CREDITS 25
+
+static int ext4_da_writepages_trans_blocks(struct inode *inode)
+{
+ int max_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+
+ /*
+ * With non-extent format the journal credit needed to
+ * insert nrblocks contiguous block is dependent on
+ * number of contiguous block. So we will limit
+ * number of contiguous block to a sane value
+ */
+ if (!(inode->i_flags & EXT4_EXTENTS_FL) &&
+ (max_blocks > EXT4_MAX_TRANS_DATA))
+ max_blocks = EXT4_MAX_TRANS_DATA;
+
+ return ext4_chunk_trans_blocks(inode, max_blocks);
+}
static int ext4_da_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
+ struct writeback_control *wbc)
{
- struct inode *inode = mapping->host;
handle_t *handle = NULL;
- int needed_blocks;
- int ret = 0;
- long to_write;
loff_t range_start = 0;
+ struct inode *inode = mapping->host;
+ int needed_blocks, ret = 0, nr_to_writebump = 0;
+ long to_write, pages_skipped = 0;
+ struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
/*
* No pages to write? This is mainly a kludge to avoid starting
* a transaction for special inodes like journal inode on last iput()
* because that could violate lock ordering on umount
*/
- if (!mapping->nrpages)
+ if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
return 0;
-
/*
- * Estimate the worse case needed credits to write out
- * EXT4_MAX_BUF_BLOCKS pages
+ * Make sure nr_to_write is >= sbi->s_mb_stream_request
+ * This make sure small files blocks are allocated in
+ * single attempt. This ensure that small files
+ * get less fragmented.
*/
- needed_blocks = EXT4_MAX_WRITEBACK_CREDITS;
+ if (wbc->nr_to_write < sbi->s_mb_stream_request) {
+ nr_to_writebump = sbi->s_mb_stream_request - wbc->nr_to_write;
+ wbc->nr_to_write = sbi->s_mb_stream_request;
+ }
- to_write = wbc->nr_to_write;
- if (!wbc->range_cyclic) {
+ if (!wbc->range_cyclic)
/*
* If range_cyclic is not set force range_cont
* and save the old writeback_index
*/
wbc->range_cont = 1;
- range_start = wbc->range_start;
- }
- while (!ret && to_write) {
+ range_start = wbc->range_start;
+ pages_skipped = wbc->pages_skipped;
+
+restart_loop:
+ to_write = wbc->nr_to_write;
+ while (!ret && to_write > 0) {
+
+ /*
+ * we insert one extent at a time. So we need
+ * credit needed for single extent allocation.
+ * journalled mode is currently not supported
+ * by delalloc
+ */
+ BUG_ON(ext4_should_journal_data(inode));
+ needed_blocks = ext4_da_writepages_trans_blocks(inode);
+
/* start a new transaction*/
handle = ext4_journal_start(inode, needed_blocks);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
+ printk(KERN_EMERG "%s: jbd2_start: "
+ "%ld pages, ino %lu; err %d\n", __func__,
+ wbc->nr_to_write, inode->i_ino, ret);
+ dump_stack();
goto out_writepages;
}
if (ext4_should_order_data(inode)) {
/*
* With ordered mode we need to add
- * the inode to the journal handle
+ * the inode to the journal handl
* when we do block allocation.
*/
ret = ext4_jbd2_file_inode(handle, inode);
ext4_journal_stop(handle);
goto out_writepages;
}
-
}
- /*
- * set the max dirty pages could be write at a time
- * to fit into the reserved transaction credits
- */
- if (wbc->nr_to_write > EXT4_MAX_WRITEBACK_PAGES)
- wbc->nr_to_write = EXT4_MAX_WRITEBACK_PAGES;
to_write -= wbc->nr_to_write;
ret = mpage_da_writepages(mapping, wbc,
- ext4_da_get_block_write);
+ ext4_da_get_block_write);
ext4_journal_stop(handle);
- if (wbc->nr_to_write) {
+ if (ret == MPAGE_DA_EXTENT_TAIL) {
+ /*
+ * got one extent now try with
+ * rest of the pages
+ */
+ to_write += wbc->nr_to_write;
+ ret = 0;
+ } else if (wbc->nr_to_write) {
/*
* There is no more writeout needed
* or we requested for a noblocking writeout
wbc->nr_to_write = to_write;
}
-out_writepages:
- wbc->nr_to_write = to_write;
- if (range_start)
+ if (wbc->range_cont && (pages_skipped != wbc->pages_skipped)) {
+ /* We skipped pages in this loop */
wbc->range_start = range_start;
+ wbc->nr_to_write = to_write +
+ wbc->pages_skipped - pages_skipped;
+ wbc->pages_skipped = pages_skipped;
+ goto restart_loop;
+ }
+
+out_writepages:
+ wbc->nr_to_write = to_write - nr_to_writebump;
+ wbc->range_start = range_start;
return ret;
}
* the modification of a single pages into a single transaction,
* which may include multiple chunks of block allocations.
*
- * This could be called via ext4_write_begin() or later
- * ext4_da_writepages() in delalyed allocation case.
+ * This could be called via ext4_write_begin()
*
- * In both case it's possible that we could allocating multiple
- * chunks of blocks. We need to consider the worse case, when
+ * We need to consider the worse case, when
* one new block per extent.
*/
int ext4_writepage_trans_blocks(struct inode *inode)
projects / linux-2.6-omap-h63xx.git / blobdiff