[PATCH 6.4 046/800] svcrdma: Prevent page release when nothing was received

Greg Kroah-Hartman
2023-07-16T19:55:00Z

From: Chuck Lever <chuck.lever@oracle.com>

[ Upstream commit baf6d18b116b7dc84ed5e212c3a89f17cdc3f28c ]

I noticed that svc_rqst_release_pages() was still unnecessarily
releasing a page when svc_rdma_recvfrom() returns zero.

Fixes: a53d5cb0646a ("svcrdma: Avoid releasing a page in svc_xprt_release()")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index a22fe7587fa6f..70207d8a318a4 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -796,6 +796,12 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
struct svc_rdma_recv_ctxt *ctxt;
int ret;

+ /* Prevent svc_xprt_release() from releasing pages in rq_pages
+ * when returning 0 or an error.
+ */
+ rqstp->rq_respages = rqstp->rq_pages;
+ rqstp->rq_next_page = rqstp->rq_respages;
+
rqstp->rq_xprt_ctxt = NULL;

ctxt = NULL;
@@ -819,12 +825,6 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
DMA_FROM_DEVICE);
svc_rdma_build_arg_xdr(rqstp, ctxt);

- /* Prevent svc_xprt_release from releasing pages in rq_pages
- * if we return 0 or an error.
- */
- rqstp->rq_respages = rqstp->rq_pages;
- rqstp->rq_next_page = rqstp->rq_respages;
-
ret = svc_rdma_xdr_decode_req(&rqstp->rq_arg, ctxt);
if (ret < 0)
goto out_err;
--
2.39.2