From: Chuck Lever <chuck.lever@oracle.com>
To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org
Subject: [PATCH v1 5/6] xprtrdma: Fix MR list handling
Date: Wed, 09 Oct 2019 13:07:43 -0400 [thread overview]
Message-ID: <20191009170743.2978.11370.stgit@manet.1015granger.net> (raw)
In-Reply-To: <20191009170721.2978.128.stgit@manet.1015granger.net>
Close some holes introduced by commit 6dc6ec9e04c4 ("xprtrdma: Cache
free MRs in each rpcrdma_req") that could result in list corruption.
In addition, the result that is tabulated in @count is no longer
used, so @count is removed.
Fixes: 6dc6ec9e04c4 ("xprtrdma: Cache free MRs in each rpcrdma_req")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
net/sunrpc/xprtrdma/verbs.c | 41 +++++++++++++++++++++--------------------
1 file changed, 21 insertions(+), 20 deletions(-)
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 3a1a31c..82361e7 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -79,7 +79,6 @@
static void rpcrdma_reps_destroy(struct rpcrdma_buffer *buf);
static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt);
static void rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf);
-static void rpcrdma_mr_free(struct rpcrdma_mr *mr);
static struct rpcrdma_regbuf *
rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
gfp_t flags);
@@ -966,7 +965,7 @@ struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt)
mr->mr_xprt = r_xprt;
spin_lock(&buf->rb_lock);
- list_add(&mr->mr_list, &buf->rb_mrs);
+ rpcrdma_mr_push(mr, &buf->rb_mrs);
list_add(&mr->mr_all, &buf->rb_all_mrs);
spin_unlock(&buf->rb_lock);
}
@@ -1183,10 +1182,19 @@ int rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
*/
void rpcrdma_req_destroy(struct rpcrdma_req *req)
{
+ struct rpcrdma_mr *mr;
+
list_del(&req->rl_all);
- while (!list_empty(&req->rl_free_mrs))
- rpcrdma_mr_free(rpcrdma_mr_pop(&req->rl_free_mrs));
+ while ((mr = rpcrdma_mr_pop(&req->rl_free_mrs))) {
+ struct rpcrdma_buffer *buf = &mr->mr_xprt->rx_buf;
+
+ spin_lock(&buf->rb_lock);
+ list_del(&mr->mr_all);
+ spin_unlock(&buf->rb_lock);
+
+ frwr_release_mr(mr);
+ }
rpcrdma_regbuf_free(req->rl_recvbuf);
rpcrdma_regbuf_free(req->rl_sendbuf);
@@ -1194,24 +1202,28 @@ void rpcrdma_req_destroy(struct rpcrdma_req *req)
kfree(req);
}
-static void
-rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf)
+/**
+ * rpcrdma_mrs_destroy - Release all of a transport's MRs
+ * @buf: controlling buffer instance
+ *
+ * Relies on caller holding the transport send lock to protect
+ * removing mr->mr_list from req->rl_free_mrs safely.
+ */
+static void rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf)
{
struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
rx_buf);
struct rpcrdma_mr *mr;
- unsigned int count;
- count = 0;
spin_lock(&buf->rb_lock);
while ((mr = list_first_entry_or_null(&buf->rb_all_mrs,
struct rpcrdma_mr,
mr_all)) != NULL) {
+ list_del(&mr->mr_list);
list_del(&mr->mr_all);
spin_unlock(&buf->rb_lock);
frwr_release_mr(mr);
- count++;
spin_lock(&buf->rb_lock);
}
spin_unlock(&buf->rb_lock);
@@ -1284,17 +1296,6 @@ void rpcrdma_mr_put(struct rpcrdma_mr *mr)
rpcrdma_mr_push(mr, &mr->mr_req->rl_free_mrs);
}
-static void rpcrdma_mr_free(struct rpcrdma_mr *mr)
-{
- struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
-
- mr->mr_req = NULL;
- spin_lock(&buf->rb_lock);
- rpcrdma_mr_push(mr, &buf->rb_mrs);
- spin_unlock(&buf->rb_lock);
-}
-
/**
* rpcrdma_buffer_get - Get a request buffer
* @buffers: Buffer pool from which to obtain a buffer
next prev parent reply other threads:[~2019-10-09 17:07 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-09 17:07 [PATCH v1 1/6] xprtrdma: Add unique trace points for posting Local Invalidate WRs Chuck Lever
2019-10-09 17:07 ` [PATCH v1 2/6] xprtrdma: Connection becomes unstable after a reconnect Chuck Lever
2019-10-09 17:07 ` [PATCH v1 3/6] xprtrdma: Initialize rb_credits in one place Chuck Lever
2019-10-09 17:07 ` [PATCH v1 4/6] xprtrdma: Close window between waking RPC senders and posting Receives Chuck Lever
2019-10-09 17:07 ` Chuck Lever [this message]
2019-10-09 17:07 ` [PATCH v1 6/6] xprtrdma: Manage MRs in context of a single connection Chuck Lever
2019-10-09 17:10 ` [PATCH v1 1/6] xprtrdma: Add unique trace points for posting Local Invalidate WRs Chuck Lever
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