NFSD: Update the NFSv2 READ argument decoder to use struct xdr_stream

The code that sets up rq_vec is refactored so that it is now
adjacent to the nfsd_read() call site where it is used.

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

1 files changed, 12 insertions, 24 deletions

diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
index f3189e1be20f..1eacaa2c13a9 100644
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -246,33 +246,21 @@ nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p)
 int
 nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p)
 {
+	struct xdr_stream *xdr = &rqstp->rq_arg_stream;
 	struct nfsd_readargs *args = rqstp->rq_argp;
-	unsigned int len;
-	int v;
-	p = decode_fh(p, &args->fh);
-	if (!p)
-		return 0;
+	u32 totalcount;
 
-	args->offset    = ntohl(*p++);
-	len = args->count     = ntohl(*p++);
-	p++; /* totalcount - unused */
-
-	len = min_t(unsigned int, len, NFSSVC_MAXBLKSIZE_V2);
+	if (!svcxdr_decode_fhandle(xdr, &args->fh))
+		return 0;
+	if (xdr_stream_decode_u32(xdr, &args->offset) < 0)
+		return 0;
+	if (xdr_stream_decode_u32(xdr, &args->count) < 0)
+		return 0;
+	/* totalcount is ignored */
+	if (xdr_stream_decode_u32(xdr, &totalcount) < 0)
+		return 0;
 
-	/* set up somewhere to store response.
-	 * We take pages, put them on reslist and include in iovec
-	 */
-	v=0;
-	while (len > 0) {
-		struct page *p = *(rqstp->rq_next_page++);
-
-		rqstp->rq_vec[v].iov_base = page_address(p);
-		rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
-		len -= rqstp->rq_vec[v].iov_len;
-		v++;
-	}
-	args->vlen = v;
-	return xdr_argsize_check(rqstp, p);
+	return 1;
 }
 
 int