NFSD: Replace READ* macros in nfsd4_decode_compound()

And clean-up: Now that we have removed the DECODE_TAIL macro from
nfsd4_decode_compound(), we observe that there's no benefit for
nfsd4_decode_compound() to return nfs_ok or nfserr_bad_xdr only to
have its sole caller convert those values to one or zero,
respectively. Have nfsd4_decode_compound() return 1/0 instead.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index a3cfc1d..f8b5750 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -186,28 +186,6 @@ svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
        return p;
 }
 
-/**
- * savemem - duplicate a chunk of memory for later processing
- * @argp: NFSv4 compound argument structure to be freed with
- * @p: pointer to be duplicated
- * @nbytes: length to be duplicated
- *
- * Returns a pointer to a copy of @nbytes bytes of memory at @p
- * that are preserved until processing of the NFSv4 compound
- * operation described by @argp finishes.
- */
-static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
-{
-       void *ret;
-
-       ret = svcxdr_tmpalloc(argp, nbytes);
-       if (!ret)
-               return NULL;
-       memcpy(ret, p, nbytes);
-       return ret;
-}
-
-
 /*
  * NFSv4 basic data type decoders
  */
@@ -2372,43 +2350,54 @@ nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
        return true;
 }
 
-static __be32
+static int
 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
 {
-       DECODE_HEAD;
        struct nfsd4_op *op;
        bool cachethis = false;
        int auth_slack= argp->rqstp->rq_auth_slack;
        int max_reply = auth_slack + 8; /* opcnt, status */
        int readcount = 0;
        int readbytes = 0;
+       __be32 *p;
        int i;
 
-       READ_BUF(4);
-       argp->taglen = be32_to_cpup(p++);
-       READ_BUF(argp->taglen);
-       SAVEMEM(argp->tag, argp->taglen);
-       READ_BUF(8);
-       argp->minorversion = be32_to_cpup(p++);
-       argp->opcnt = be32_to_cpup(p++);
-       max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
-
-       if (argp->taglen > NFSD4_MAX_TAGLEN)
-               goto xdr_error;
+       if (xdr_stream_decode_u32(argp->xdr, &argp->taglen) < 0)
+               return 0;
+       max_reply += XDR_UNIT;
+       argp->tag = NULL;
+       if (unlikely(argp->taglen)) {
+               if (argp->taglen > NFSD4_MAX_TAGLEN)
+                       return 0;
+               p = xdr_inline_decode(argp->xdr, argp->taglen);
+               if (!p)
+                       return 0;
+               argp->tag = svcxdr_tmpalloc(argp, argp->taglen);
+               if (!argp->tag)
+                       return 0;
+               memcpy(argp->tag, p, argp->taglen);
+               max_reply += xdr_align_size(argp->taglen);
+       }
+
+       if (xdr_stream_decode_u32(argp->xdr, &argp->minorversion) < 0)
+               return 0;
+       if (xdr_stream_decode_u32(argp->xdr, &argp->opcnt) < 0)
+               return 0;
+
        /*
         * NFS4ERR_RESOURCE is a more helpful error than GARBAGE_ARGS
         * here, so we return success at the xdr level so that
         * nfsd4_proc can handle this is an NFS-level error.
         */
        if (argp->opcnt > NFSD_MAX_OPS_PER_COMPOUND)
-               return 0;
+               return 1;
 
        if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
                argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
                if (!argp->ops) {
                        argp->ops = argp->iops;
                        dprintk("nfsd: couldn't allocate room for COMPOUND\n");
-                       goto xdr_error;
+                       return 0;
                }
        }
 
@@ -2420,7 +2409,7 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
                op->replay = NULL;
 
                if (xdr_stream_decode_u32(argp->xdr, &op->opnum) < 0)
-                       return nfserr_bad_xdr;
+                       return 0;
                if (nfsd4_opnum_in_range(argp, op)) {
                        op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
                        if (op->status != nfs_ok)
@@ -2467,7 +2456,7 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
        if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
                clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
 
-       DECODE_TAIL;
+       return 1;
 }
 
 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
@@ -5479,7 +5468,7 @@ nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p)
        args->ops = args->iops;
        args->rqstp = rqstp;
 
-       return !nfsd4_decode_compound(args);
+       return nfsd4_decode_compound(args);
 }
 
 int