NFSD: Update READ3arg 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, 18 insertions, 5 deletions

diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index 4b66f055141b..acdf47179a38 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -144,25 +144,38 @@ nfsd3_proc_read(struct svc_rqst *rqstp)
 {
 	struct nfsd3_readargs *argp = rqstp->rq_argp;
 	struct nfsd3_readres *resp = rqstp->rq_resp;
-	u32	max_blocksize = svc_max_payload(rqstp);
-	unsigned long cnt = min(argp->count, max_blocksize);
+	u32 max_blocksize = svc_max_payload(rqstp);
+	unsigned int len;
+	int v;
+
+	argp->count = min_t(u32, argp->count, max_blocksize);
 
 	dprintk("nfsd: READ(3) %s %lu bytes at %Lu\n",
 				SVCFH_fmt(&argp->fh),
 				(unsigned long) argp->count,
 				(unsigned long long) argp->offset);
 
+	v = 0;
+	len = argp->count;
+	while (len > 0) {
+		struct page *page = *(rqstp->rq_next_page++);
+
+		rqstp->rq_vec[v].iov_base = page_address(page);
+		rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
+		len -= rqstp->rq_vec[v].iov_len;
+		v++;
+	}
+
 	/* Obtain buffer pointer for payload.
 	 * 1 (status) + 22 (post_op_attr) + 1 (count) + 1 (eof)
 	 * + 1 (xdr opaque byte count) = 26
 	 */
-	resp->count = cnt;
+	resp->count = argp->count;
 	svc_reserve_auth(rqstp, ((1 + NFS3_POST_OP_ATTR_WORDS + 3)<<2) + resp->count +4);
 
 	fh_copy(&resp->fh, &argp->fh);
 	resp->status = nfsd_read(rqstp, &resp->fh, argp->offset,
-				 rqstp->rq_vec, argp->vlen, &resp->count,
-				 &resp->eof);
+				 rqstp->rq_vec, v, &resp->count, &resp->eof);
 	return rpc_success;
 }