BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb;
- /* Account for allocated meta_blocks */
- mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
-
- /* update fs free blocks counter for truncate case */
- percpu_counter_add(&sbi->s_freeblocks_counter, mdb_free);
+ if (mdb_free) {
+ /* Account for allocated meta_blocks */
+ mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks;
+
+ /* update fs dirty blocks counter */
+ percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free);
+ EXT4_I(inode)->i_allocated_meta_blocks = 0;
+ EXT4_I(inode)->i_reserved_meta_blocks = mdb;
+ }
/* update per-inode reservations */
BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks);
EXT4_I(inode)->i_reserved_data_blocks -= used;
- BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks);
- EXT4_I(inode)->i_reserved_meta_blocks = mdb;
- EXT4_I(inode)->i_allocated_meta_blocks = 0;
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
/*
static int ext4_da_reserve_space(struct inode *inode, int nrblocks)
{
+ int retries = 0;
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
unsigned long md_needed, mdblocks, total = 0;
* in order to allocate nrblocks
* worse case is one extent per block
*/
+repeat:
spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks;
mdblocks = ext4_calc_metadata_amount(inode, total);
md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks;
total = md_needed + nrblocks;
- if (ext4_has_free_blocks(sbi, total) < total) {
+ if (ext4_claim_free_blocks(sbi, total)) {
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+ if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
+ yield();
+ goto repeat;
+ }
return -ENOSPC;
}
- /* reduce fs free blocks counter */
- percpu_counter_sub(&sbi->s_freeblocks_counter, total);
-
EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
EXT4_I(inode)->i_reserved_meta_blocks = mdblocks;
release = to_free + mdb_free;
- /* update fs free blocks counter for truncate case */
- percpu_counter_add(&sbi->s_freeblocks_counter, release);
+ /* update fs dirty blocks counter for truncate case */
+ percpu_counter_sub(&sbi->s_dirtyblocks_counter, release);
/* update per-inode reservations */
BUG_ON(to_free > EXT4_I(inode)->i_reserved_data_blocks);
struct writeback_control *wbc;
int io_done;
long pages_written;
+ int retval;
};
/*
pagevec_init(&pvec, 0);
while (index <= end) {
- nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+ /*
+ * We can use PAGECACHE_TAG_DIRTY lookup here because
+ * even though we have cleared the dirty flag on the page
+ * We still keep the page in the radix tree with tag
+ * PAGECACHE_TAG_DIRTY. See clear_page_dirty_for_io.
+ * The PAGECACHE_TAG_DIRTY is cleared in set_page_writeback
+ * which is called via the below writepage callback.
+ */
+ nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+ PAGECACHE_TAG_DIRTY,
+ min(end - index,
+ (pgoff_t)PAGEVEC_SIZE-1) + 1);
if (nr_pages == 0)
break;
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
- index = page->index;
- if (index > end)
- break;
- index++;
-
BUG_ON(!PageLocked(page));
BUG_ON(PageWriteback(page));
pages_skipped = mpd->wbc->pages_skipped;
err = mapping->a_ops->writepage(page, mpd->wbc);
- if (!err)
+ if (!err && (pages_skipped == mpd->wbc->pages_skipped))
+ /*
+ * have successfully written the page
+ * without skipping the same
+ */
mpd->pages_written++;
/*
* In error case, we have to continue because
unmap_underlying_metadata(bdev, bh->b_blocknr + i);
}
+static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd,
+ sector_t logical, long blk_cnt)
+{
+ int nr_pages, i;
+ pgoff_t index, end;
+ struct pagevec pvec;
+ struct inode *inode = mpd->inode;
+ struct address_space *mapping = inode->i_mapping;
+
+ index = logical >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ end = (logical + blk_cnt - 1) >>
+ (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ while (index <= end) {
+ nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
+ if (nr_pages == 0)
+ break;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+ index = page->index;
+ if (index > end)
+ break;
+ index++;
+
+ BUG_ON(!PageLocked(page));
+ BUG_ON(PageWriteback(page));
+ block_invalidatepage(page, 0);
+ ClearPageUptodate(page);
+ unlock_page(page);
+ }
+ }
+ return;
+}
+
+static void ext4_print_free_blocks(struct inode *inode)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ printk(KERN_EMERG "Total free blocks count %lld\n",
+ ext4_count_free_blocks(inode->i_sb));
+ printk(KERN_EMERG "Free/Dirty block details\n");
+ printk(KERN_EMERG "free_blocks=%lld\n",
+ percpu_counter_sum(&sbi->s_freeblocks_counter));
+ printk(KERN_EMERG "dirty_blocks=%lld\n",
+ percpu_counter_sum(&sbi->s_dirtyblocks_counter));
+ printk(KERN_EMERG "Block reservation details\n");
+ printk(KERN_EMERG "i_reserved_data_blocks=%lu\n",
+ EXT4_I(inode)->i_reserved_data_blocks);
+ printk(KERN_EMERG "i_reserved_meta_blocks=%lu\n",
+ EXT4_I(inode)->i_reserved_meta_blocks);
+ return;
+}
+
/*
* mpage_da_map_blocks - go through given space
*
* The function skips space we know is already mapped to disk blocks.
*
*/
-static void mpage_da_map_blocks(struct mpage_da_data *mpd)
+static int mpage_da_map_blocks(struct mpage_da_data *mpd)
{
int err = 0;
- struct buffer_head *lbh = &mpd->lbh;
- sector_t next = lbh->b_blocknr;
struct buffer_head new;
+ struct buffer_head *lbh = &mpd->lbh;
+ sector_t next;
/*
* We consider only non-mapped and non-allocated blocks
*/
if (buffer_mapped(lbh) && !buffer_delay(lbh))
- return;
-
+ return 0;
new.b_state = lbh->b_state;
new.b_blocknr = 0;
new.b_size = lbh->b_size;
-
+ next = lbh->b_blocknr;
/*
* If we didn't accumulate anything
* to write simply return
*/
if (!new.b_size)
- return;
+ return 0;
err = mpd->get_block(mpd->inode, next, &new, 1);
- if (err)
- return;
+ if (err) {
+
+ /* If get block returns with error
+ * we simply return. Later writepage
+ * will redirty the page and writepages
+ * will find the dirty page again
+ */
+ if (err == -EAGAIN)
+ return 0;
+
+ if (err == -ENOSPC &&
+ ext4_count_free_blocks(mpd->inode->i_sb)) {
+ mpd->retval = err;
+ return 0;
+ }
+
+ /*
+ * get block failure will cause us
+ * to loop in writepages. Because
+ * a_ops->writepage won't be able to
+ * make progress. The page will be redirtied
+ * by writepage and writepages will again
+ * try to write the same.
+ */
+ printk(KERN_EMERG "%s block allocation failed for inode %lu "
+ "at logical offset %llu with max blocks "
+ "%zd with error %d\n",
+ __func__, mpd->inode->i_ino,
+ (unsigned long long)next,
+ lbh->b_size >> mpd->inode->i_blkbits, err);
+ printk(KERN_EMERG "This should not happen.!! "
+ "Data will be lost\n");
+ if (err == -ENOSPC) {
+ ext4_print_free_blocks(mpd->inode);
+ }
+ /* invlaidate all the pages */
+ ext4_da_block_invalidatepages(mpd, next,
+ lbh->b_size >> mpd->inode->i_blkbits);
+ return err;
+ }
BUG_ON(new.b_size == 0);
if (buffer_new(&new))
if (buffer_delay(lbh) || buffer_unwritten(lbh))
mpage_put_bnr_to_bhs(mpd, next, &new);
- return;
+ return 0;
}
#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
* 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);
- mpage_da_submit_io(mpd);
+ if (mpage_da_map_blocks(mpd) == 0)
+ 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?
*/
* and start IO on them using writepage()
*/
if (mpd->next_page != mpd->first_page) {
- mpage_da_map_blocks(mpd);
- mpage_da_submit_io(mpd);
+ if (mpage_da_map_blocks(mpd) == 0)
+ mpage_da_submit_io(mpd);
/*
* skip rest of the page in the page_vec
*/
return 0;
}
+/*
+ * write_cache_pages_da - walk the list of dirty pages of the given
+ * address space and call the callback function (which usually writes
+ * the pages).
+ *
+ * This is a forked version of write_cache_pages(). Differences:
+ * Range cyclic is ignored.
+ * no_nrwrite_index_update is always presumed true
+ */
+static int write_cache_pages_da(struct address_space *mapping,
+ struct writeback_control *wbc,
+ struct mpage_da_data *mpd)
+{
+ struct backing_dev_info *bdi = mapping->backing_dev_info;
+ int ret = 0;
+ int done = 0;
+ struct pagevec pvec;
+ int nr_pages;
+ pgoff_t index;
+ pgoff_t end; /* Inclusive */
+ long nr_to_write = wbc->nr_to_write;
+
+ if (wbc->nonblocking && bdi_write_congested(bdi)) {
+ wbc->encountered_congestion = 1;
+ return 0;
+ }
+
+ pagevec_init(&pvec, 0);
+ index = wbc->range_start >> PAGE_CACHE_SHIFT;
+ end = wbc->range_end >> PAGE_CACHE_SHIFT;
+
+ while (!done && (index <= end)) {
+ int i;
+
+ nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+ PAGECACHE_TAG_DIRTY,
+ min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
+ if (nr_pages == 0)
+ break;
+
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+
+ /*
+ * At this point, the page may be truncated or
+ * invalidated (changing page->mapping to NULL), or
+ * even swizzled back from swapper_space to tmpfs file
+ * mapping. However, page->index will not change
+ * because we have a reference on the page.
+ */
+ if (page->index > end) {
+ done = 1;
+ break;
+ }
+
+ lock_page(page);
+
+ /*
+ * Page truncated or invalidated. We can freely skip it
+ * then, even for data integrity operations: the page
+ * has disappeared concurrently, so there could be no
+ * real expectation of this data interity operation
+ * even if there is now a new, dirty page at the same
+ * pagecache address.
+ */
+ if (unlikely(page->mapping != mapping)) {
+continue_unlock:
+ unlock_page(page);
+ continue;
+ }
+
+ if (!PageDirty(page)) {
+ /* someone wrote it for us */
+ goto continue_unlock;
+ }
+
+ if (PageWriteback(page)) {
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ wait_on_page_writeback(page);
+ else
+ goto continue_unlock;
+ }
+
+ BUG_ON(PageWriteback(page));
+ if (!clear_page_dirty_for_io(page))
+ goto continue_unlock;
+
+ ret = __mpage_da_writepage(page, wbc, mpd);
+
+ if (unlikely(ret)) {
+ if (ret == AOP_WRITEPAGE_ACTIVATE) {
+ unlock_page(page);
+ ret = 0;
+ } else {
+ done = 1;
+ break;
+ }
+ }
+
+ if (nr_to_write > 0) {
+ nr_to_write--;
+ if (nr_to_write == 0 &&
+ wbc->sync_mode == WB_SYNC_NONE) {
+ /*
+ * We stop writing back only if we are
+ * not doing integrity sync. In case of
+ * integrity sync we have to keep going
+ * because someone may be concurrently
+ * dirtying pages, and we might have
+ * synced a lot of newly appeared dirty
+ * pages, but have not synced all of the
+ * old dirty pages.
+ */
+ done = 1;
+ break;
+ }
+ }
+
+ if (wbc->nonblocking && bdi_write_congested(bdi)) {
+ wbc->encountered_congestion = 1;
+ done = 1;
+ break;
+ }
+ }
+ pagevec_release(&pvec);
+ cond_resched();
+ }
+ return ret;
+}
+
+
/*
* mpage_da_writepages - walk the list of dirty pages of the given
* address space, allocates non-allocated blocks, maps newly-allocated
*/
static int mpage_da_writepages(struct address_space *mapping,
struct writeback_control *wbc,
- get_block_t get_block)
+ struct mpage_da_data *mpd)
{
- struct mpage_da_data mpd;
- long to_write;
int ret;
- if (!get_block)
+ if (!mpd->get_block)
return generic_writepages(mapping, wbc);
- mpd.wbc = wbc;
- mpd.inode = mapping->host;
- mpd.lbh.b_size = 0;
- mpd.lbh.b_state = 0;
- mpd.lbh.b_blocknr = 0;
- 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);
+ mpd->lbh.b_size = 0;
+ mpd->lbh.b_state = 0;
+ mpd->lbh.b_blocknr = 0;
+ mpd->first_page = 0;
+ mpd->next_page = 0;
+ mpd->io_done = 0;
+ mpd->pages_written = 0;
+ mpd->retval = 0;
+ ret = write_cache_pages_da(mapping, wbc, mpd);
/*
* Handle last extent of pages
*/
- if (!mpd.io_done && mpd.next_page != mpd.first_page) {
- mpage_da_map_blocks(&mpd);
- mpage_da_submit_io(&mpd);
- }
+ if (!mpd->io_done && mpd->next_page != mpd->first_page) {
+ if (mpage_da_map_blocks(mpd) == 0)
+ mpage_da_submit_io(mpd);
- wbc->nr_to_write = to_write - mpd.pages_written;
+ mpd->io_done = 1;
+ ret = MPAGE_DA_EXTENT_TAIL;
+ }
+ wbc->nr_to_write -= mpd->pages_written;
return ret;
}
static int ext4_da_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
+ pgoff_t index;
+ int range_whole = 0;
handle_t *handle = NULL;
- loff_t range_start = 0;
+ struct mpage_da_data mpd;
struct inode *inode = mapping->host;
+ long pages_written = 0, pages_skipped;
+ int range_cyclic, cycled = 1, io_done = 0;
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);
/*
nr_to_writebump = sbi->s_mb_stream_request - wbc->nr_to_write;
wbc->nr_to_write = sbi->s_mb_stream_request;
}
+ if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
+ range_whole = 1;
+
+ range_cyclic = wbc->range_cyclic;
+ if (wbc->range_cyclic) {
+ index = mapping->writeback_index;
+ if (index)
+ cycled = 0;
+ wbc->range_start = index << PAGE_CACHE_SHIFT;
+ wbc->range_end = LLONG_MAX;
+ wbc->range_cyclic = 0;
+ } else
+ index = wbc->range_start >> PAGE_CACHE_SHIFT;
- if (!wbc->range_cyclic)
- /*
- * If range_cyclic is not set force range_cont
- * and save the old writeback_index
- */
- wbc->range_cont = 1;
+ mpd.wbc = wbc;
+ mpd.inode = mapping->host;
- range_start = wbc->range_start;
pages_skipped = wbc->pages_skipped;
-restart_loop:
- to_write = wbc->nr_to_write;
- while (!ret && to_write > 0) {
+retry:
+ while (!ret && wbc->nr_to_write > 0) {
/*
* we insert one extent at a time. So we need
goto out_writepages;
}
}
+ mpd.get_block = ext4_da_get_block_write;
+ ret = mpage_da_writepages(mapping, wbc, &mpd);
- to_write -= wbc->nr_to_write;
- ret = mpage_da_writepages(mapping, wbc,
- ext4_da_get_block_write);
ext4_journal_stop(handle);
- if (ret == MPAGE_DA_EXTENT_TAIL) {
+
+ if (mpd.retval == -ENOSPC) {
+ /* commit the transaction which would
+ * free blocks released in the transaction
+ * and try again
+ */
+ jbd2_journal_force_commit_nested(sbi->s_journal);
+ wbc->pages_skipped = pages_skipped;
+ ret = 0;
+ } else if (ret == MPAGE_DA_EXTENT_TAIL) {
/*
* got one extent now try with
* rest of the pages
*/
- to_write += wbc->nr_to_write;
+ pages_written += mpd.pages_written;
+ wbc->pages_skipped = pages_skipped;
ret = 0;
- } else if (wbc->nr_to_write) {
+ io_done = 1;
+ } else if (wbc->nr_to_write)
/*
* There is no more writeout needed
* or we requested for a noblocking writeout
* and we found the device congested
*/
- to_write += wbc->nr_to_write;
break;
- }
- wbc->nr_to_write = to_write;
}
-
- 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;
+ if (!io_done && !cycled) {
+ cycled = 1;
+ index = 0;
+ wbc->range_start = index << PAGE_CACHE_SHIFT;
+ wbc->range_end = mapping->writeback_index - 1;
+ goto retry;
}
+ if (pages_skipped != wbc->pages_skipped)
+ printk(KERN_EMERG "This should not happen leaving %s "
+ "with nr_to_write = %ld ret = %d\n",
+ __func__, wbc->nr_to_write, ret);
+
+ /* Update index */
+ index += pages_written;
+ wbc->range_cyclic = range_cyclic;
+ if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
+ /*
+ * set the writeback_index so that range_cyclic
+ * mode will write it back later
+ */
+ mapping->writeback_index = index;
out_writepages:
- wbc->nr_to_write = to_write - nr_to_writebump;
- wbc->range_start = range_start;
+ wbc->nr_to_write -= nr_to_writebump;
return ret;
}
index = pos >> PAGE_CACHE_SHIFT;
from = pos & (PAGE_CACHE_SIZE - 1);
to = from + len;
-
retry:
/*
* With delayed allocation, we don't log the i_disksize update