[PATCH 5.4 238/270] NFS: Dont move layouts to plh_return_segs list while in use

From: Greg Kroah-Hartman
Date: Mon Aug 17 2020 - 13:07:20 EST


From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

commit ff041727e9e029845857cac41aae118ead5e261b upstream.

If the layout segment is still in use for a read or a write, we should
not move it to the layout plh_return_segs list. If we do, we can end
up returning the layout while I/O is still in progress.

Fixes: e0b7d420f72a ("pNFS: Don't discard layout segments that are marked for return")
Cc: stable@xxxxxxxxxxxxxxx # v4.19+
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/nfs/pnfs.c | 12 +-----------
1 file changed, 1 insertion(+), 11 deletions(-)

--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2362,16 +2362,6 @@ out_forget:
return ERR_PTR(-EAGAIN);
}

-static int
-mark_lseg_invalid_or_return(struct pnfs_layout_segment *lseg,
- struct list_head *tmp_list)
-{
- if (!mark_lseg_invalid(lseg, tmp_list))
- return 0;
- pnfs_cache_lseg_for_layoutreturn(lseg->pls_layout, lseg);
- return 1;
-}
-
/**
* pnfs_mark_matching_lsegs_return - Free or return matching layout segments
* @lo: pointer to layout header
@@ -2408,7 +2398,7 @@ pnfs_mark_matching_lsegs_return(struct p
lseg, lseg->pls_range.iomode,
lseg->pls_range.offset,
lseg->pls_range.length);
- if (mark_lseg_invalid_or_return(lseg, tmp_list))
+ if (mark_lseg_invalid(lseg, tmp_list))
continue;
remaining++;
set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);