[PATCH v2 4/7] pNFS: Stricter ordering of layoutget and layoutreturn

trondmy
2021-01-07T05:32:30Z

If a layout return is in progress, we should wait for it to complete,
in case the layout segment we are picking up gets returned too.

Fixes: 30cb3ee299cb ("pNFS: Handle NFS4ERR_OLD_STATEID on layoutreturn by bumping the state seqid")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
fs/nfs/pnfs.c | 43 +++++++++++++++++++++----------------------
1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 16a37214aba9..fc13a3c8bc48 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2018,6 +2018,27 @@ pnfs_update_layout(struct inode *ino,
goto lookup_again;
}

+ /*
+ * Because we free lsegs when sending LAYOUTRETURN, we need to wait
+ * for LAYOUTRETURN.
+ */
+ if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
+ spin_unlock(&ino->i_lock);
+ dprintk("%s wait for layoutreturn\n", __func__);
+ lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
+ if (!IS_ERR(lseg)) {
+ pnfs_put_layout_hdr(lo);
+ dprintk("%s retrying\n", __func__);
+ trace_pnfs_update_layout(ino, pos, count, iomode, lo,
+ lseg,
+ PNFS_UPDATE_LAYOUT_RETRY);
+ goto lookup_again;
+ }
+ trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
+ PNFS_UPDATE_LAYOUT_RETURN);
+ goto out_put_layout_hdr;
+ }
+
lseg = pnfs_find_lseg(lo, &arg, strict_iomode);
if (lseg) {
trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
@@ -2070,28 +2091,6 @@ pnfs_update_layout(struct inode *ino,
nfs4_stateid_copy(&stateid, &lo->plh_stateid);
}

- /*
- * Because we free lsegs before sending LAYOUTRETURN, we need to wait
- * for LAYOUTRETURN even if first is true.
- */
- if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
- spin_unlock(&ino->i_lock);
- dprintk("%s wait for layoutreturn\n", __func__);
- lseg = ERR_PTR(pnfs_prepare_to_retry_layoutget(lo));
- if (!IS_ERR(lseg)) {
- if (first)
- pnfs_clear_first_layoutget(lo);
- pnfs_put_layout_hdr(lo);
- dprintk("%s retrying\n", __func__);
- trace_pnfs_update_layout(ino, pos, count, iomode, lo,
- lseg, PNFS_UPDATE_LAYOUT_RETRY);
- goto lookup_again;
- }
- trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
- PNFS_UPDATE_LAYOUT_RETURN);
- goto out_put_layout_hdr;
- }
-
if (pnfs_layoutgets_blocked(lo)) {
trace_pnfs_update_layout(ino, pos, count, iomode, lo, lseg,
PNFS_UPDATE_LAYOUT_BLOCKED);
--
2.29.2