[PATCH 1/3] NFSv4.x: Don't return NFS4ERR_NOMATCHING_LAYOUT if we're unmounting

[PATCH 1/3] NFSv4.x: Don't return NFS4ERR_NOMATCHING_LAYOUT if we're unmounting

[trondmy]

From: Trond Myklebust <trond.myklebust@hammerspace.com>

If the NFS super block is being unmounted, then we currently may end up
telling the server that we've forgotten the layout while it is actually
still in use by the client.
In that case, just assume that the client will soon return the layout
anyway, and so return NFS4ERR_DELAY in response to the layout recall.

Fixes: 58ac3e59235f ("NFSv4/pnfs: Clean up nfs_layout_find_inode()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/callback_proc.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index f7786e00a6a7..ed9d580826f5 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -137,12 +137,12 @@ static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
 		list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
 			if (!pnfs_layout_is_valid(lo))
 				continue;
-			if (stateid != NULL &&
-			    !nfs4_stateid_match_other(stateid, &lo->plh_stateid))
+			if (!nfs4_stateid_match_other(stateid, &lo->plh_stateid))
 				continue;
-			if (!nfs_sb_active(server->super))
-				continue;
-			inode = igrab(lo->plh_inode);
+			if (nfs_sb_active(server->super))
+				inode = igrab(lo->plh_inode);
+			else
+				inode = ERR_PTR(-EAGAIN);
 			rcu_read_unlock();
 			if (inode)
 				return inode;
@@ -176,9 +176,10 @@ static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
 				continue;
 			if (nfsi->layout != lo)
 				continue;
-			if (!nfs_sb_active(server->super))
-				continue;
-			inode = igrab(lo->plh_inode);
+			if (nfs_sb_active(server->super))
+				inode = igrab(lo->plh_inode);
+			else
+				inode = ERR_PTR(-EAGAIN);
 			rcu_read_unlock();
 			if (inode)
 				return inode;
-- 
2.30.2

[PATCH 2/3] NFS: Don't discard pNFS layout segments that are marked for return

[trondmy]

From: Trond Myklebust <trond.myklebust@hammerspace.com>

If the pNFS layout segment is marked with the NFS_LSEG_LAYOUTRETURN
flag, then the assumption is that it has some reporting requirement
to perform through a layoutreturn (e.g. flexfiles layout stats or error
information).

Fixes: e0b7d420f72a ("pNFS: Don't discard layout segments that are marked for return")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/pnfs.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 102b66e0bdef..33574f47601f 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2468,6 +2468,9 @@ pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
 
 	assert_spin_locked(&lo->plh_inode->i_lock);
 
+	if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags))
+		tmp_list = &lo->plh_return_segs;
+
 	list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 		if (pnfs_match_lseg_recall(lseg, return_range, seq)) {
 			dprintk("%s: marking lseg %p iomode %d "
@@ -2475,6 +2478,8 @@ pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
 				lseg, lseg->pls_range.iomode,
 				lseg->pls_range.offset,
 				lseg->pls_range.length);
+			if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
+				tmp_list = &lo->plh_return_segs;
 			if (mark_lseg_invalid(lseg, tmp_list))
 				continue;
 			remaining++;
-- 
2.30.2

[PATCH 3/3] NFSv4.1: Simplify layout return in pnfs_layout_process()

[trondmy]

From: Trond Myklebust <trond.myklebust@hammerspace.com>

If the server hands us a layout that does not match the one we currently
hold, then have pnfs_mark_matching_lsegs_return() just ditch the old
layout if NFS_LSEG_LAYOUTRETURN is not set.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/pnfs.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 33574f47601f..fa22b4be9212 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2410,9 +2410,7 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
 			.iomode = IOMODE_ANY,
 			.length = NFS4_MAX_UINT64,
 		};
-		pnfs_set_plh_return_info(lo, IOMODE_ANY, 0);
-		pnfs_mark_matching_lsegs_return(lo, &lo->plh_return_segs,
-						&range, 0);
+		pnfs_mark_matching_lsegs_return(lo, &free_me, &range, 0);
 		goto out_forget;
 	} else {
 		/* We have a completely new layout */
-- 
2.30.2