scsi: Revert "scsi: core: Do not increase scsi_device's iorequest_cnt if dispatch failed"

The "atomic_inc(&cmd->device->iorequest_cnt)" in scsi_queue_rq() would
cause kernel panic because cmd->device may be freed after returning from
scsi_dispatch_cmd().

This reverts commit cfee29f.

Signed-off-by: Wenchao Hao <[email protected]>
Reported-by: Ming Lei <[email protected]>
Closes: https://lore.kernel.org/r/[email protected]
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Ming Lei <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: wenchao-hao

drivers/scsi/scsi_lib.c

@@ -1463,6 +1463,8 @@ static int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
 	struct Scsi_Host *host = cmd->device->host;
 	int rtn = 0;
 
+	atomic_inc(&cmd->device->iorequest_cnt);
+
 	/* check if the device is still usable */
 	if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
 		/* in SDEV_DEL we error all commands. DID_NO_CONNECT
@@ -1761,7 +1763,6 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
 		goto out_dec_host_busy;
 	}
 
-	atomic_inc(&cmd->device->iorequest_cnt);
 	return BLK_STS_OK;
 
 out_dec_host_busy: