nfsd: nfs4 minorversion decoder vectors

Have separate vectors of operation decoders for each minorversion.
Obsolete ops in newer minorversions have default implementation returning
nfserr_opnotsupp.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

1 files changed, 14 insertions, 3 deletions

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 653951c73e31..a40bec53fa66 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1039,11 +1039,21 @@ static nfsd4_dec nfsd4_dec_ops[] = {
         [OP_RELEASE_LOCKOWNER]  (nfsd4_dec)nfsd4_decode_release_lockowner,
 };
 
+struct nfsd4_minorversion_ops {
+        nfsd4_dec *decoders;
+        int nops;
+};
+
+static struct nfsd4_minorversion_ops nfsd4_minorversion[] = {
+        [0] { nfsd4_dec_ops, ARRAY_SIZE(nfsd4_dec_ops) },
+};
+
 static __be32
 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
 {
         DECODE_HEAD;
         struct nfsd4_op *op;
+        struct nfsd4_minorversion_ops *ops;
         int i;
 
         /*
@@ -1073,9 +1083,10 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
                 }
         }
 
-        if (argp->minorversion != 0)
+        if (argp->minorversion >= ARRAY_SIZE(nfsd4_minorversion))
                 argp->opcnt = 0;
 
+        ops = &nfsd4_minorversion[argp->minorversion];
         for (i = 0; i < argp->opcnt; i++) {
                 op = &argp->ops[i];
                 op->replay = NULL;
@@ -1113,8 +1124,8 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
                 }
                 op->opnum = ntohl(*argp->p++);
 
-                if (op->opnum >= OP_ACCESS && op->opnum < ARRAY_SIZE(nfsd4_dec_ops))
-                        op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
+                if (op->opnum >= OP_ACCESS && op->opnum < ops->nops)
+                        op->status = ops->decoders[op->opnum](argp, &op->u);
                 else {
                         op->opnum = OP_ILLEGAL;
                         op->status = nfserr_op_illegal;