From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit e814eecbe3bbeaa8b004d25a4b8974d232b765a9 ]
Commit 07d0ff3b0cd2 ("svcrdma: Clean up Read chunk path") moved the page saver logic so that it gets executed event when an error occurs. In that case, the I/O is never posted, and those pages are then leaked. Errors in this path, however, are quite rare.
Fixes: 07d0ff3b0cd2 ("svcrdma: Clean up Read chunk path") Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- net/sunrpc/xprtrdma/svc_rdma_rw.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-)
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c index 4fc0ce1270894..22f1352638151 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -679,7 +679,6 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp, struct svc_rdma_read_info *info, __be32 *p) { - unsigned int i; int ret;
ret = -EINVAL; @@ -702,12 +701,6 @@ static int svc_rdma_build_read_chunk(struct svc_rqst *rqstp, info->ri_chunklen += rs_length; }
- /* Pages under I/O have been copied to head->rc_pages. - * Prevent their premature release by svc_xprt_release() . - */ - for (i = 0; i < info->ri_readctxt->rc_page_count; i++) - rqstp->rq_pages[i] = NULL; - return ret; }
@@ -802,6 +795,26 @@ static int svc_rdma_build_pz_read_chunk(struct svc_rqst *rqstp, return ret; }
+/* Pages under I/O have been copied to head->rc_pages. Ensure they + * are not released by svc_xprt_release() until the I/O is complete. + * + * This has to be done after all Read WRs are constructed to properly + * handle a page that is part of I/O on behalf of two different RDMA + * segments. + * + * Do this only if I/O has been posted. Otherwise, we do indeed want + * svc_xprt_release() to clean things up properly. + */ +static void svc_rdma_save_io_pages(struct svc_rqst *rqstp, + const unsigned int start, + const unsigned int num_pages) +{ + unsigned int i; + + for (i = start; i < num_pages + start; i++) + rqstp->rq_pages[i] = NULL; +} + /** * svc_rdma_recv_read_chunk - Pull a Read chunk from the client * @rdma: controlling RDMA transport @@ -855,6 +868,7 @@ int svc_rdma_recv_read_chunk(struct svcxprt_rdma *rdma, struct svc_rqst *rqstp, ret = svc_rdma_post_chunk_ctxt(&info->ri_cc); if (ret < 0) goto out_err; + svc_rdma_save_io_pages(rqstp, 0, head->rc_page_count); return 0;
out_err: