From: Josef Bacik josef@toxicpanda.com
[ Upstream commit de6346ecbc8f5591ebd6c44ac164e8b8671d71d7 ]
We already do this for the most part, except in timeout and clear_req. For the timeout case we take the lock after we grab a ref on the config, but that isn't really necessary because we're safe to touch the cmd at this point, so just move the order around.
For the clear_req cause this is initiated by the user, so again is safe.
Reviewed-by: Mike Christie mchristi@redhat.com Signed-off-by: Josef Bacik josef@toxicpanda.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/nbd.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 9650777d0aaf1..7301fe55084bf 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -351,17 +351,16 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, struct nbd_device *nbd = cmd->nbd; struct nbd_config *config;
+ if (!mutex_trylock(&cmd->lock)) + return BLK_EH_RESET_TIMER; + if (!refcount_inc_not_zero(&nbd->config_refs)) { cmd->status = BLK_STS_TIMEOUT; + mutex_unlock(&cmd->lock); goto done; } config = nbd->config;
- if (!mutex_trylock(&cmd->lock)) { - nbd_config_put(nbd); - return BLK_EH_RESET_TIMER; - } - if (config->num_connections > 1) { dev_err_ratelimited(nbd_to_dev(nbd), "Connection timed out, retrying (%d/%d alive)\n", @@ -755,7 +754,10 @@ static bool nbd_clear_req(struct request *req, void *data, bool reserved) { struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req);
+ mutex_lock(&cmd->lock); cmd->status = BLK_STS_IOERR; + mutex_unlock(&cmd->lock); + blk_mq_complete_request(req); return true; }