Use these helpers in a few spots to demonstrate their use.
The remaining open-coded discriminator checks in rpcrdma will be
addressed in subsequent patches.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
include/linux/sunrpc/xdr.h | 26 ++++++++++++++++++++++++++
net/sunrpc/xprtrdma/rpc_rdma.c | 12 ++++++------
net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 17 ++++++++---------
3 files changed, 40 insertions(+), 15 deletions(-)
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 22c207b2425f..5a6a81b7cd9f 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -474,6 +474,32 @@ xdr_stream_encode_uint32_array(struct xdr_stream *xdr,
return ret;
}
+/**
+ * xdr_item_is_absent - symbolically handle XDR discriminators
+ * @p: pointer to undecoded discriminator
+ *
+ * Return values:
+ * %true if the following XDR item is absent
+ * %false if the following XDR item is present
+ */
+static inline bool xdr_item_is_absent(const __be32 *p)
+{
+ return *p == xdr_zero;
+}
+
+/**
+ * xdr_item_is_present - symbolically handle XDR discriminators
+ * @p: pointer to undecoded discriminator
+ *
+ * Return values:
+ * %true if the following XDR item is present
+ * %false if the following XDR item is absent
+ */
+static inline bool xdr_item_is_present(const __be32 *p)
+{
+ return *p != xdr_zero;
+}
+
/**
* xdr_stream_decode_u32 - Decode a 32-bit integer
* @xdr: pointer to xdr_stream
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index 935bbef2f7be..feecd1f55f18 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -1133,11 +1133,11 @@ rpcrdma_is_bcall(struct rpcrdma_xprt *r_xprt, struct rpcrdma_rep *rep)
p = xdr_inline_decode(xdr, 0);
/* Chunk lists */
- if (*p++ != xdr_zero)
+ if (xdr_item_is_present(p++))
return false;
- if (*p++ != xdr_zero)
+ if (xdr_item_is_present(p++))
return false;
- if (*p++ != xdr_zero)
+ if (xdr_item_is_present(p++))
return false;
/* RPC header */
@@ -1215,7 +1215,7 @@ static int decode_read_list(struct xdr_stream *xdr)
p = xdr_inline_decode(xdr, sizeof(*p));
if (unlikely(!p))
return -EIO;
- if (unlikely(*p != xdr_zero))
+ if (unlikely(xdr_item_is_present(p)))
return -EIO;
return 0;
}
@@ -1234,7 +1234,7 @@ static int decode_write_list(struct xdr_stream *xdr, u32 *length)
p = xdr_inline_decode(xdr, sizeof(*p));
if (unlikely(!p))
return -EIO;
- if (*p == xdr_zero)
+ if (xdr_item_is_absent(p))
break;
if (!first)
return -EIO;
@@ -1256,7 +1256,7 @@ static int decode_reply_chunk(struct xdr_stream *xdr, u32 *length)
return -EIO;
*length = 0;
- if (*p != xdr_zero)
+ if (xdr_item_is_present(p))
if (decode_write_chunk(xdr, length))
return -EIO;
return 0;
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index c072ce61b393..5e78067889f3 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -419,7 +419,7 @@ static bool xdr_check_read_list(struct svc_rdma_recv_ctxt *rctxt)
len = 0;
first = true;
- while (*p != xdr_zero) {
+ while (xdr_item_is_present(p)) {
p = xdr_inline_decode(&rctxt->rc_stream,
rpcrdma_readseg_maxsz * sizeof(*p));
if (!p)
@@ -500,7 +500,7 @@ static bool xdr_check_write_list(struct svc_rdma_recv_ctxt *rctxt)
if (!p)
return false;
rctxt->rc_write_list = p;
- while (*p != xdr_zero) {
+ while (xdr_item_is_present(p)) {
if (!xdr_check_write_chunk(rctxt, MAX_BYTES_WRITE_CHUNK))
return false;
++chcount;
@@ -532,12 +532,11 @@ static bool xdr_check_reply_chunk(struct svc_rdma_recv_ctxt *rctxt)
p = xdr_inline_decode(&rctxt->rc_stream, sizeof(*p));
if (!p)
return false;
- rctxt->rc_reply_chunk = p;
- if (*p != xdr_zero) {
+ rctxt->rc_reply_chunk = NULL;
+ if (xdr_item_is_present(p)) {
if (!xdr_check_write_chunk(rctxt, MAX_BYTES_SPECIAL_CHUNK))
return false;
- } else {
- rctxt->rc_reply_chunk = NULL;
+ rctxt->rc_reply_chunk = p;
}
return true;
}
@@ -568,7 +567,7 @@ static void svc_rdma_get_inv_rkey(struct svcxprt_rdma *rdma,
p += rpcrdma_fixed_maxsz;
/* Read list */
- while (*p++ != xdr_zero) {
+ while (xdr_item_is_present(p++)) {
p++; /* position */
if (inv_rkey == xdr_zero)
inv_rkey = *p;
@@ -578,7 +577,7 @@ static void svc_rdma_get_inv_rkey(struct svcxprt_rdma *rdma,
}
/* Write list */
- while (*p++ != xdr_zero) {
+ while (xdr_item_is_present(p++)) {
segcount = be32_to_cpup(p++);
for (i = 0; i < segcount; i++) {
if (inv_rkey == xdr_zero)
@@ -590,7 +589,7 @@ static void svc_rdma_get_inv_rkey(struct svcxprt_rdma *rdma,
}
/* Reply chunk */
- if (*p++ != xdr_zero) {
+ if (xdr_item_is_present(p++)) {
segcount = be32_to_cpup(p++);
for (i = 0; i < segcount; i++) {
if (inv_rkey == xdr_zero)
