diff options
| author | Jan Kara <jack@suse.cz> | 2013-06-28 16:04:02 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-07-27 05:34:22 +0100 |
| commit | 5ba9a2e746033d2886d56d21b4298f5da7178d12 (patch) | |
| tree | d0bc6f15b01580084c749ce1cc2cc0936e03bb86 /fs | |
| parent | e0a59ed79b08eea4ce3d88ddf8ef781265301b90 (diff) | |
writeback: Fix periodic writeback after fs mount
commit a5faeaf9109578e65e1a32e2a3e76c8b47e7dcb6 upstream.
Code in blkdev.c moves a device inode to default_backing_dev_info when
the last reference to the device is put and moves the device inode back
to its bdi when the first reference is acquired. This includes moving to
wb.b_dirty list if the device inode is dirty. The code however doesn't
setup timer to wake corresponding flusher thread and while wb.b_dirty
list is non-empty __mark_inode_dirty() will not set it up either. Thus
periodic writeback is effectively disabled until a sync(2) call which can
lead to unexpected data loss in case of crash or power failure.
Fix the problem by setting up a timer for periodic writeback in case we
add the first dirty inode to wb.b_dirty list in bdev_inode_switch_bdi().
Reported-by: Bert De Jonghe <Bert.DeJonghe@amplidata.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/block_dev.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index 53ab27351b04..c10326753915 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -55,17 +55,24 @@ static void bdev_inode_switch_bdi(struct inode *inode, struct backing_dev_info *dst) { struct backing_dev_info *old = inode->i_data.backing_dev_info; + bool wakeup_bdi = false; if (unlikely(dst == old)) /* deadlock avoidance */ return; bdi_lock_two(&old->wb, &dst->wb); spin_lock(&inode->i_lock); inode->i_data.backing_dev_info = dst; - if (inode->i_state & I_DIRTY) + if (inode->i_state & I_DIRTY) { + if (bdi_cap_writeback_dirty(dst) && !wb_has_dirty_io(&dst->wb)) + wakeup_bdi = true; list_move(&inode->i_wb_list, &dst->wb.b_dirty); + } spin_unlock(&inode->i_lock); spin_unlock(&old->wb.list_lock); spin_unlock(&dst->wb.list_lock); + + if (wakeup_bdi) + bdi_wakeup_thread_delayed(dst); } sector_t blkdev_max_block(struct block_device *bdev) |