[PATCH v2 6/6] NFS: Add support for decoding multiple segments

[Anna Schumaker <Anna.Schumaker@netapp.com>]

We now have everything we need to read holes and then shift data to
where it's supposed to be.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
 fs/nfs/nfs42xdr.c | 40 ++++++++++++++++++++++------------------
 1 file changed, 22 insertions(+), 18 deletions(-)

diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 17126e8..010af55 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -201,11 +201,11 @@ static int decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_res *re
 	p = xdr_decode_hyper(p, &offset);
 	count = be32_to_cpup(p);
 
-	recvd = xdr_read_pages(xdr, count);
+	recvd = xdr_align_data(xdr, res->count, count);
 	if (recvd < count)
 		res->eof = 0;
 
-	res->count = recvd;
+	res->count += recvd;
 	return 0;
 out_overflow:
 	print_overflow_msg(__func__, xdr);
@@ -225,11 +225,11 @@ static int decode_read_plus_hole(struct xdr_stream *xdr, struct nfs_pgio_res *re
 	p = xdr_decode_hyper(p, &offset);
 	p = xdr_decode_hyper(p, &length);
 
-	recvd = xdr_expand_hole(xdr, 0, length);
+	recvd = xdr_expand_hole(xdr, res->count, length);
 	if (recvd < length)
 		res->eof = 0;
 
-	res->count = recvd;
+	res->count += recvd;
 	return 0;
 out_overflow:
 	print_overflow_msg(__func__, xdr);
@@ -240,7 +240,7 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 {
 	__be32 *p;
 	int status, type;
-	uint32_t segments;
+	uint32_t i, segments;
 
 	status = decode_op_hdr(xdr, OP_READ_PLUS);
 	if (status)
@@ -253,20 +253,24 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
 	res->count = 0;
 	res->eof = be32_to_cpup(p++);
 	segments = be32_to_cpup(p++);
-	if (segments == 0)
-		return 0;
 
-	p = xdr_inline_decode(xdr, 4);
-	if (unlikely(!p))
-		goto out_overflow;
-
-	type = be32_to_cpup(p++);
-	if (type == NFS4_CONTENT_DATA)
-		status = decode_read_plus_data(xdr, res);
-	else
-		status = decode_read_plus_hole(xdr, res);
-
-	if (segments > 1)
+	for (i = 0; i < segments; i++) {
+		p = xdr_inline_decode(xdr, 4);
+		if (unlikely(!p))
+			goto out_overflow;
+
+		type = be32_to_cpup(p);
+		if (type == NFS4_CONTENT_DATA)
+			status = decode_read_plus_data(xdr, res);
+		else
+			status = decode_read_plus_hole(xdr, res);
+		if (status)
+			break;
+		if (res->count == xdr->buf->page_len)
+			break;
+	}
+
+	if (i < segments)
 		res->eof = 0;
 	return status;
 out_overflow:
-- 
2.2.2