NFS: Add SECINFO_NO_NAME procedure

If the client is using NFS v4.1, then we can use SECINFO_NO_NAME to find
the secflavor for the initial mount.  If the server doesn't support
SECINFO_NO_NAME then I fall back on the "guess and check" method used
for v4.0 mounts.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 1555c74dd336..c8c069a6319b 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -343,6 +343,8 @@ static int nfs4_stat_to_errno(int);
                                 1 /* FIXME: opaque lrf_body always empty at the moment */)
 #define decode_layoutreturn_maxsz (op_decode_hdr_maxsz + \
                                 1 + decode_stateid_maxsz)
+#define encode_secinfo_no_name_maxsz (op_encode_hdr_maxsz + 1)
+#define decode_secinfo_no_name_maxsz decode_secinfo_maxsz
 #else /* CONFIG_NFS_V4_1 */
 #define encode_sequence_maxsz   0
 #define decode_sequence_maxsz   0
@@ -772,6 +774,14 @@ static int nfs4_stat_to_errno(int);
                                 decode_sequence_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_layoutreturn_maxsz)
+#define NFS4_enc_secinfo_no_name_sz     (compound_encode_hdr_maxsz + \
+                                        encode_sequence_maxsz + \
+                                        encode_putrootfh_maxsz +\
+                                        encode_secinfo_no_name_maxsz)
+#define NFS4_dec_secinfo_no_name_sz     (compound_decode_hdr_maxsz + \
+                                        decode_sequence_maxsz + \
+                                        decode_putrootfh_maxsz + \
+                                        decode_secinfo_no_name_maxsz)
 
 const u32 nfs41_maxwrite_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
                                       compound_encode_hdr_maxsz +
@@ -1938,6 +1948,20 @@ encode_layoutreturn(struct xdr_stream *xdr,
         hdr->nops++;
         hdr->replen += decode_layoutreturn_maxsz;
 }
+
+static int
+encode_secinfo_no_name(struct xdr_stream *xdr,
+                       const struct nfs41_secinfo_no_name_args *args,
+                       struct compound_hdr *hdr)
+{
+        __be32 *p;
+        p = reserve_space(xdr, 8);
+        *p++ = cpu_to_be32(OP_SECINFO_NO_NAME);
+        *p++ = cpu_to_be32(args->style);
+        hdr->nops++;
+        hdr->replen += decode_secinfo_no_name_maxsz;
+        return 0;
+}
 #endif /* CONFIG_NFS_V4_1 */
 
 /*
@@ -2790,6 +2814,25 @@ static void nfs4_xdr_enc_layoutreturn(struct rpc_rqst *req,
         encode_layoutreturn(xdr, args, &hdr);
         encode_nops(&hdr);
 }
+
+/*
+ * Encode SECINFO_NO_NAME request
+ */
+static int nfs4_xdr_enc_secinfo_no_name(struct rpc_rqst *req,
+                                        struct xdr_stream *xdr,
+                                        struct nfs41_secinfo_no_name_args *args)
+{
+        struct compound_hdr hdr = {
+                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
+        };
+
+        encode_compound_hdr(xdr, req, &hdr);
+        encode_sequence(xdr, &args->seq_args, &hdr);
+        encode_putrootfh(xdr, &hdr);
+        encode_secinfo_no_name(xdr, args, &hdr);
+        encode_nops(&hdr);
+        return 0;
+}
 #endif /* CONFIG_NFS_V4_1 */
 
 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
@@ -6467,6 +6510,30 @@ static int nfs4_xdr_dec_layoutcommit(struct rpc_rqst *rqstp,
 out:
         return status;
 }
+
+/*
+ * Decode SECINFO_NO_NAME response
+ */
+static int nfs4_xdr_dec_secinfo_no_name(struct rpc_rqst *rqstp,
+                                        struct xdr_stream *xdr,
+                                        struct nfs4_secinfo_res *res)
+{
+        struct compound_hdr hdr;
+        int status;
+
+        status = decode_compound_hdr(xdr, &hdr);
+        if (status)
+                goto out;
+        status = decode_sequence(xdr, &res->seq_res, rqstp);
+        if (status)
+                goto out;
+        status = decode_putrootfh(xdr);
+        if (status)
+                goto out;
+        status = decode_secinfo(xdr, res);
+out:
+        return status;
+}
 #endif /* CONFIG_NFS_V4_1 */
 
 /**
@@ -6669,6 +6736,7 @@ struct rpc_procinfo	nfs4_procedures[] = {
         PROC(LAYOUTGET,         enc_layoutget,          dec_layoutget),
         PROC(LAYOUTCOMMIT,      enc_layoutcommit,       dec_layoutcommit),
         PROC(LAYOUTRETURN,      enc_layoutreturn,       dec_layoutreturn),
+        PROC(SECINFO_NO_NAME,   enc_secinfo_no_name,    dec_secinfo_no_name),
 #endif /* CONFIG_NFS_V4_1 */
 };