NFS: Fix data corruption caused by congestion.

when AOP_WRITEPAGE_ACTIVATE is returned (as NFS does when it detects
congestion) it is important that the page is redirtied.
nfs_writepage_locked() doesn't do this, so files can become corrupted as
writes can be lost.

Note that this is not needed in v6.8 as AOP_WRITEPAGE_ACTIVATE cannot be
returned.  It is needed for kernels v5.18..v6.7.  From 6.3 onward the patch
is different as it needs to mention "folio", not "page".

Reported-and-tested-by: Jacek Tomaka <Jacek.Tomaka@poczta.fm>
Fixes: 6df25e5853 ("nfs: remove reliance on bdi congestion")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
NeilBrown 2024-02-28 10:25:49 +11:00 committed by Greg Kroah-Hartman
parent 04dd4403ff
commit 831e9e63cc

View File

@ -667,8 +667,10 @@ static int nfs_writepage_locked(struct page *page,
int err;
if (wbc->sync_mode == WB_SYNC_NONE &&
NFS_SERVER(inode)->write_congested)
NFS_SERVER(inode)->write_congested) {
redirty_page_for_writepage(wbc, page);
return AOP_WRITEPAGE_ACTIVATE;
}
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
nfs_pageio_init_write(&pgio, inode, 0,