On Wed, Dec 11, 2013 at 08:59:36PM +0100, Jan Kara wrote: > Commit 4f8ad655dbc8 "writeback: Refactor writeback_single_inode()" added > a condition to skip clean inode. However this is wrong in WB_SYNC_ALL > mode because there we also want to wait for outstanding writeback on > possibly clean inode. This was causing occasional data corruption issues > on NFS because it uses sync_inode() to make sure all outstanding writes > are flushed to the server before truncating the inode and with > sync_inode() returning prematurely file was sometimes extended back > by an outstanding write after it was truncated. > > So modify the test to also check for pages under writeback in > WB_SYNC_ALL mode. Applied to the writeback tree. Thank you, Jan! Regards, Fengguang > CC: stable@xxxxxxxxxxxxxxx # >= 3.5 > Fixes: 4f8ad655dbc82cf05d2edc11e66b78a42d38bf93 > Reported-and-tested-by: Dan Duval <dan.duval@xxxxxxxxxx> > Signed-off-by: Jan Kara <jack@xxxxxxx> > --- > fs/fs-writeback.c | 15 +++++++++------ > 1 file changed, 9 insertions(+), 6 deletions(-) > > Fenguang, can you please merge this patch? Thanks! > > diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c > index 1f4a10ece2f1..e0259a163f98 100644 > --- a/fs/fs-writeback.c > +++ b/fs/fs-writeback.c > @@ -516,13 +516,16 @@ writeback_single_inode(struct inode *inode, struct bdi_writeback *wb, > } > WARN_ON(inode->i_state & I_SYNC); > /* > - * Skip inode if it is clean. We don't want to mess with writeback > - * lists in this function since flusher thread may be doing for example > - * sync in parallel and if we move the inode, it could get skipped. So > - * here we make sure inode is on some writeback list and leave it there > - * unless we have completely cleaned the inode. > + * Skip inode if it is clean and we have no outstanding writeback in > + * WB_SYNC_ALL mode. We don't want to mess with writeback lists in this > + * function since flusher thread may be doing for example sync in > + * parallel and if we move the inode, it could get skipped. So here we > + * make sure inode is on some writeback list and leave it there unless > + * we have completely cleaned the inode. > */ > - if (!(inode->i_state & I_DIRTY)) > + if (!(inode->i_state & I_DIRTY) && > + (wbc->sync_mode != WB_SYNC_ALL || > + !mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK))) > goto out; > inode->i_state |= I_SYNC; > spin_unlock(&inode->i_lock); > -- > 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
