[PATCH 01/21] pNFS: Fix CB_NOTIFY_DEVICEID CHANGE to consume ndc_immediate

[Benjamin Coddington <ben.coddington@hammerspace.com>]

decode_devicenotify_args() gated consuming the trailing ndc_immediate
boolean on cbd_layout_type instead of cbd_notify_type.  cbd_layout_type
holds the pNFS layout type (e.g. 4 for flexfiles) and is never equal to
NOTIFY_DEVICEID4_CHANGE (2), so ndc_immediate was never consumed: it was
silently lost for a single CHANGE, and a multi-item cnda_changes<> array
misaligned after the first item and failed with NFS4ERR_INVAL/BADXDR.

Key the decode off the notification type.

Fixes: 1be5683b03a7 ("pnfs: CB_NOTIFY_DEVICEID")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Benjamin Coddington <bcodding@hammerspace.com>
---
 fs/nfs/callback_xdr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/callback_xdr.c b/fs/nfs/callback_xdr.c
index 4382baddc9ee..04af8b9078a0 100644
--- a/fs/nfs/callback_xdr.c
+++ b/fs/nfs/callback_xdr.c
@@ -312,7 +312,7 @@ __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
 		memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
 		p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
 
-		if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
+		if (dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) {
 			p = xdr_inline_decode(xdr, sizeof(uint32_t));
 			if (unlikely(p == NULL)) {
 				status = htonl(NFS4ERR_BADXDR);
-- 
2.53.0