nfs: convert setclientid and exchange_id encoders to use clp->cl_owner_id

...instead of buffers that are part of their arg structs. We already
hold a reference to the client, so we might as well use the allocated
buffer. In the event that we can't allocate the clp->cl_owner_id, then
just return -ENOMEM.

Note too that we switch from a GFP_KERNEL allocation here to GFP_NOFS.
It's possible we could end up trying to do a SETCLIENTID or EXCHANGE_ID
in order to reclaim some memory, and the GFP_KERNEL allocations in the
existing code could cause recursion back into NFS reclaim.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 0aea97841d30..f58e8a979397 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1667,13 +1667,14 @@ static void encode_setclientid(struct xdr_stream *xdr, const struct nfs4_setclie
         encode_op_hdr(xdr, OP_SETCLIENTID, decode_setclientid_maxsz, hdr);
         encode_nfs4_verifier(xdr, setclientid->sc_verifier);
 
-        encode_string(xdr, setclientid->sc_name_len, setclientid->sc_name);
+        encode_string(xdr, strlen(setclientid->sc_clnt->cl_owner_id),
+                        setclientid->sc_clnt->cl_owner_id);
         p = reserve_space(xdr, 4);
         *p = cpu_to_be32(setclientid->sc_prog);
         encode_string(xdr, setclientid->sc_netid_len, setclientid->sc_netid);
         encode_string(xdr, setclientid->sc_uaddr_len, setclientid->sc_uaddr);
         p = reserve_space(xdr, 4);
-        *p = cpu_to_be32(setclientid->sc_cb_ident);
+        *p = cpu_to_be32(setclientid->sc_clnt->cl_cb_ident);
 }
 
 static void encode_setclientid_confirm(struct xdr_stream *xdr, const struct nfs4_setclientid_res *arg, struct compound_hdr *hdr)
@@ -1747,7 +1748,8 @@ static void encode_exchange_id(struct xdr_stream *xdr,
         encode_op_hdr(xdr, OP_EXCHANGE_ID, decode_exchange_id_maxsz, hdr);
         encode_nfs4_verifier(xdr, args->verifier);
 
-        encode_string(xdr, args->id_len, args->id);
+        encode_string(xdr, strlen(args->client->cl_owner_id),
+                        args->client->cl_owner_id);
 
         encode_uint32(xdr, args->flags);
         encode_uint32(xdr, args->state_protect.how);