NFSv4.1 Fix gdia_maxcount calculation to fit in ca_maxresponsesize

The GETDEVICEINFO gdia_maxcount represents all of the data being returned
within the GETDEVICEINFO4resok structure and includes the XDR overhead.

The CREATE_SESSION ca_maxresponsesize is the maximum reply and includes the RPC
headers (including security flavor credentials and verifiers).

Split out the struct pnfs_device field maxcount which is the gdia_maxcount
from the pglen field which is the reply (the total) buffer length.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 4be8d135ed61..27cc76d88f9a 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -853,6 +853,12 @@ const u32 nfs41_maxread_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
                                      decode_sequence_maxsz +
                                      decode_putfh_maxsz) *
                                     XDR_UNIT);
+
+const u32 nfs41_maxgetdevinfo_overhead = ((RPC_MAX_REPHEADER_WITH_AUTH +
+                                           compound_decode_hdr_maxsz +
+                                           decode_sequence_maxsz) *
+                                          XDR_UNIT);
+EXPORT_SYMBOL_GPL(nfs41_maxgetdevinfo_overhead);
 #endif /* CONFIG_NFS_V4_1 */
 
 static const umode_t nfs_type2fmt[] = {
@@ -1889,7 +1895,7 @@ encode_getdeviceinfo(struct xdr_stream *xdr,
         p = xdr_encode_opaque_fixed(p, args->pdev->dev_id.data,
                                     NFS4_DEVICEID4_SIZE);
         *p++ = cpu_to_be32(args->pdev->layout_type);
-        *p++ = cpu_to_be32(args->pdev->pglen);          /* gdia_maxcount */
+        *p++ = cpu_to_be32(args->pdev->maxcount);       /* gdia_maxcount */
         *p++ = cpu_to_be32(0);                          /* bitmap length 0 */
 }