NFS COPY xdr handle async reply

If server returns async reply, it must include a callback stateid,
wr_callback_id in the write_response4.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

2 files changed, 13 insertions, 10 deletions

diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 09a540d035b8..205c3567ea08 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -389,21 +389,23 @@ static int decode_write_response(struct xdr_stream *xdr,
                                  struct nfs42_write_res *res)
 {
         __be32 *p;
+        int status, count;
 
-        p = xdr_inline_decode(xdr, 4 + 8 + 4);
+        p = xdr_inline_decode(xdr, 4);
         if (unlikely(!p))
                 goto out_overflow;
-
-        /*
-         * We never use asynchronous mode, so warn if a server returns
-         * a stateid.
-         */
-        if (unlikely(*p != 0)) {
-                pr_err_once("%s: server has set unrequested "
-                                "asynchronous mode\n", __func__);
+        count = be32_to_cpup(p);
+        if (count > 1)
                 return -EREMOTEIO;
+        else if (count == 1) {
+                status = decode_opaque_fixed(xdr, &res->stateid,
+                                NFS4_STATEID_SIZE);
+                if (unlikely(status))
+                        goto out_overflow;
         }
-        p++;
+        p = xdr_inline_decode(xdr, 8 + 4);
+        if (unlikely(!p))
+                goto out_overflow;
         p = xdr_decode_hyper(p, &res->count);
         res->verifier.committed = be32_to_cpup(p);
         return decode_verifier(xdr, &res->verifier.verifier);
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 85e928a56cef..06ddfa31cbef 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1391,6 +1391,7 @@ struct nfs42_copy_args {
 };
 
 struct nfs42_write_res {
+        nfs4_stateid            stateid;
         u64                     count;
         struct nfs_writeverf    verifier;
 };