2022-07-27 19:51:15

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH] SUNRPC: Don't reuse bvec on retransmission of the request

From: Trond Myklebust <[email protected]>

If a request is re-encoded and then retransmitted, we need to make sure
that we also re-encode the bvec, in case the page lists have changed.

Fixes: ff053dbbaffe ("SUNRPC: Move the call to xprt_send_pagedata() out of xprt_sock_sendmsg()")
Signed-off-by: Trond Myklebust <[email protected]>
---
include/linux/sunrpc/xprt.h | 3 ++-
net/sunrpc/clnt.c | 1 -
net/sunrpc/xprt.c | 26 +++++++++++++++++---------
net/sunrpc/xprtsock.c | 12 ++----------
4 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 0d51b9f9ea37..b9f59aabee53 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/include/linux/sunrpc/xprt.h
@@ -144,7 +144,8 @@ struct rpc_xprt_ops {
unsigned short (*get_srcport)(struct rpc_xprt *xprt);
int (*buf_alloc)(struct rpc_task *task);
void (*buf_free)(struct rpc_task *task);
- int (*prepare_request)(struct rpc_rqst *req);
+ int (*prepare_request)(struct rpc_rqst *req,
+ struct xdr_buf *buf);
int (*send_request)(struct rpc_rqst *req);
void (*wait_for_reply_request)(struct rpc_task *task);
void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task);
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index bbfc47f03480..b098e707ad41 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -1870,7 +1870,6 @@ rpc_xdr_encode(struct rpc_task *task)
req->rq_snd_buf.head[0].iov_len = 0;
xdr_init_encode(&xdr, &req->rq_snd_buf,
req->rq_snd_buf.head[0].iov_base, req);
- xdr_free_bvec(&req->rq_snd_buf);
if (rpc_encode_header(task, &xdr))
return;

diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 44348c9f4b00..7c195737e451 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -73,7 +73,7 @@ static void xprt_init(struct rpc_xprt *xprt, struct net *net);
static __be32 xprt_alloc_xid(struct rpc_xprt *xprt);
static void xprt_destroy(struct rpc_xprt *xprt);
static void xprt_request_init(struct rpc_task *task);
-static int xprt_request_prepare(struct rpc_rqst *req);
+static int xprt_request_prepare(struct rpc_rqst *req, struct xdr_buf *buf);

static DEFINE_SPINLOCK(xprt_list_lock);
static LIST_HEAD(xprt_list);
@@ -1149,7 +1149,7 @@ xprt_request_enqueue_receive(struct rpc_task *task)
if (!xprt_request_need_enqueue_receive(task, req))
return 0;

- ret = xprt_request_prepare(task->tk_rqstp);
+ ret = xprt_request_prepare(task->tk_rqstp, &req->rq_rcv_buf);
if (ret)
return ret;
spin_lock(&xprt->queue_lock);
@@ -1179,8 +1179,10 @@ xprt_request_dequeue_receive_locked(struct rpc_task *task)
{
struct rpc_rqst *req = task->tk_rqstp;

- if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate))
+ if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) {
xprt_request_rb_remove(req->rq_xprt, req);
+ xdr_free_bvec(&req->rq_rcv_buf);
+ }
}

/**
@@ -1336,8 +1338,14 @@ xprt_request_enqueue_transmit(struct rpc_task *task)
{
struct rpc_rqst *pos, *req = task->tk_rqstp;
struct rpc_xprt *xprt = req->rq_xprt;
+ int ret;

if (xprt_request_need_enqueue_transmit(task, req)) {
+ ret = xprt_request_prepare(task->tk_rqstp, &req->rq_snd_buf);
+ if (ret) {
+ task->tk_status = ret;
+ return;
+ }
req->rq_bytes_sent = 0;
spin_lock(&xprt->queue_lock);
/*
@@ -1397,6 +1405,7 @@ xprt_request_dequeue_transmit_locked(struct rpc_task *task)
} else
list_del(&req->rq_xmit2);
atomic_long_dec(&req->rq_xprt->xmit_queuelen);
+ xdr_free_bvec(&req->rq_snd_buf);
}

/**
@@ -1433,8 +1442,6 @@ xprt_request_dequeue_xprt(struct rpc_task *task)
test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) ||
xprt_is_pinned_rqst(req)) {
spin_lock(&xprt->queue_lock);
- xprt_request_dequeue_transmit_locked(task);
- xprt_request_dequeue_receive_locked(task);
while (xprt_is_pinned_rqst(req)) {
set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate);
spin_unlock(&xprt->queue_lock);
@@ -1442,6 +1449,8 @@ xprt_request_dequeue_xprt(struct rpc_task *task)
spin_lock(&xprt->queue_lock);
clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate);
}
+ xprt_request_dequeue_transmit_locked(task);
+ xprt_request_dequeue_receive_locked(task);
spin_unlock(&xprt->queue_lock);
}
}
@@ -1449,18 +1458,19 @@ xprt_request_dequeue_xprt(struct rpc_task *task)
/**
* xprt_request_prepare - prepare an encoded request for transport
* @req: pointer to rpc_rqst
+ * @buf: pointer to send/rcv xdr_buf
*
* Calls into the transport layer to do whatever is needed to prepare
* the request for transmission or receive.
* Returns error, or zero.
*/
static int
-xprt_request_prepare(struct rpc_rqst *req)
+xprt_request_prepare(struct rpc_rqst *req, struct xdr_buf *buf)
{
struct rpc_xprt *xprt = req->rq_xprt;

if (xprt->ops->prepare_request)
- return xprt->ops->prepare_request(req);
+ return xprt->ops->prepare_request(req, buf);
return 0;
}

@@ -1961,8 +1971,6 @@ void xprt_release(struct rpc_task *task)
spin_unlock(&xprt->transport_lock);
if (req->rq_buffer)
xprt->ops->buf_free(task);
- xdr_free_bvec(&req->rq_rcv_buf);
- xdr_free_bvec(&req->rq_snd_buf);
if (req->rq_cred != NULL)
put_rpccred(req->rq_cred);
if (req->rq_release_snd_buf)
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index eba1be9984f8..e976007f4fd0 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -822,17 +822,9 @@ static int xs_stream_nospace(struct rpc_rqst *req, bool vm_wait)
return ret;
}

-static int
-xs_stream_prepare_request(struct rpc_rqst *req)
+static int xs_stream_prepare_request(struct rpc_rqst *req, struct xdr_buf *buf)
{
- gfp_t gfp = rpc_task_gfp_mask();
- int ret;
-
- ret = xdr_alloc_bvec(&req->rq_snd_buf, gfp);
- if (ret < 0)
- return ret;
- xdr_free_bvec(&req->rq_rcv_buf);
- return xdr_alloc_bvec(&req->rq_rcv_buf, gfp);
+ return xdr_alloc_bvec(buf, rpc_task_gfp_mask());
}

/*
--
2.37.1