Both nbd_send_cmd() and nbd_handle_cmd() return either a negative error
number or a positive blk_status_t value. nbd_queue_rq() converts these
return values into a blk_status_t value. There is a bug in the conversion
code: if nbd_send_cmd() returns BLK_STS_RESOURCE, nbd_queue_rq() should
return BLK_STS_RESOURCE instead of BLK_STS_OK. Fix this, move the
conversion code into nbd_handle_cmd() and fix the remaining sparse warnings.
This patch fixes the following sparse warnings:
drivers/block/nbd.c:673:32: warning: incorrect type in return expression (different base types)
drivers/block/nbd.c:673:32: expected int
drivers/block/nbd.c:673:32: got restricted blk_status_t [usertype]
drivers/block/nbd.c:714:48: warning: incorrect type in return expression (different base types)
drivers/block/nbd.c:714:48: expected int
drivers/block/nbd.c:714:48: got restricted blk_status_t [usertype]
drivers/block/nbd.c:1120:21: warning: incorrect type in assignment (different base types)
drivers/block/nbd.c:1120:21: expected int [assigned] ret
drivers/block/nbd.c:1120:21: got restricted blk_status_t [usertype]
drivers/block/nbd.c:1125:16: warning: incorrect type in return expression (different base types)
drivers/block/nbd.c:1125:16: expected restricted blk_status_t
drivers/block/nbd.c:1125:16: got int [assigned] ret
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Josef Bacik <jbacik@xxxxxx>
Cc: Yu Kuai <yukuai3@xxxxxxxxxx>
Cc: Markus Pargmann <mpa@xxxxxxxxxxxxxx>
Fixes: fc17b6534eb8 ("blk-mq: switch ->queue_rq return value to blk_status_t")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
---
drivers/block/nbd.c | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 29e43ab1650c..22a79a62cc4e 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -588,6 +588,10 @@ static inline int was_interrupted(int result)
return result == -ERESTARTSYS || result == -EINTR;
}
+/*
+ * Returns BLK_STS_RESOURCE if the caller should retry after a delay. Returns
+ * -EAGAIN if the caller should requeue @cmd. Returns -EIO if sending failed.
+ */
static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
{
struct request *req = blk_mq_rq_from_pdu(cmd);
@@ -670,7 +674,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
nsock->sent = sent;
}
set_bit(NBD_CMD_REQUEUED, &cmd->flags);
- return BLK_STS_RESOURCE;
+ return (__force int)BLK_STS_RESOURCE;
}
dev_err_ratelimited(disk_to_dev(nbd->disk),
"Send control failed (result %d)\n", result);
@@ -711,7 +715,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
nsock->pending = req;
nsock->sent = sent;
set_bit(NBD_CMD_REQUEUED, &cmd->flags);
- return BLK_STS_RESOURCE;
+ return (__force int)BLK_STS_RESOURCE;
}
dev_err(disk_to_dev(nbd->disk),
"Send data failed (result %d)\n",
@@ -1008,7 +1012,7 @@ static int wait_for_reconnect(struct nbd_device *nbd)
return !test_bit(NBD_RT_DISCONNECTED, &config->runtime_flags);
}
-static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)
+static blk_status_t nbd_handle_cmd(struct nbd_cmd *cmd, int index)
{
struct request *req = blk_mq_rq_from_pdu(cmd);
struct nbd_device *nbd = cmd->nbd;
@@ -1022,14 +1026,14 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)
if (!config) {
dev_err_ratelimited(disk_to_dev(nbd->disk),
"Socks array is empty\n");
- return -EINVAL;
+ return BLK_STS_IOERR;
}
if (index >= config->num_connections) {
dev_err_ratelimited(disk_to_dev(nbd->disk),
"Attempted send on invalid socket\n");
nbd_config_put(nbd);
- return -EINVAL;
+ return BLK_STS_IOERR;
}
cmd->status = BLK_STS_OK;
again:
@@ -1052,7 +1056,7 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)
*/
sock_shutdown(nbd);
nbd_config_put(nbd);
- return -EIO;
+ return BLK_STS_IOERR;
}
goto again;
}
@@ -1065,7 +1069,7 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)
blk_mq_start_request(req);
if (unlikely(nsock->pending && nsock->pending != req)) {
nbd_requeue_cmd(cmd);
- ret = 0;
+ ret = BLK_STS_OK;
goto out;
}
/*
@@ -1084,19 +1088,19 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index)
"Request send failed, requeueing\n");
nbd_mark_nsock_dead(nbd, nsock, 1);
nbd_requeue_cmd(cmd);
- ret = 0;
+ ret = BLK_STS_OK;
}
out:
mutex_unlock(&nsock->tx_lock);
nbd_config_put(nbd);
- return ret;
+ return ret < 0 ? BLK_STS_IOERR : (__force blk_status_t)ret;
}
static blk_status_t nbd_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct nbd_cmd *cmd = blk_mq_rq_to_pdu(bd->rq);
- int ret;
+ blk_status_t ret;
/*
* Since we look at the bio's to send the request over the network we
@@ -1116,10 +1120,6 @@ static blk_status_t nbd_queue_rq(struct blk_mq_hw_ctx *hctx,
* appropriate.
*/
ret = nbd_handle_cmd(cmd, hctx->queue_num);
- if (ret < 0)
- ret = BLK_STS_IOERR;
- else if (!ret)
- ret = BLK_STS_OK;
mutex_unlock(&cmd->lock);
return ret;
