From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Tue, 4 Aug 2020 16:30:30 -0400
Subject: [PATCH] NFS: Don't move layouts to plh_return_segs list while in use
Git-commit: ff041727e9e029845857cac41aae118ead5e261b
Patch-mainline: v5.9-rc1
References: git-fixes

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@vger.kernel.org # v4.19+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Acked-by: NeilBrown <neilb@suse.com>

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

--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2306,16 +2306,6 @@ 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
@@ -2352,7 +2342,7 @@ 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);