}
EXPORT_SYMBOL(scsi_init_io);
+/**
+ * scsi_initialize_rq - initialize struct scsi_cmnd.req
+ *
+ * Called from inside blk_get_request().
+ */
+void scsi_initialize_rq(struct request *rq)
+{
+ struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
+
+ scsi_req_init(&cmd->req);
+}
+EXPORT_SYMBOL(scsi_initialize_rq);
+
+ /* Add a command to the list used by the aacraid and dpt_i2o drivers */
+ void scsi_add_cmd_to_list(struct scsi_cmnd *cmd)
+ {
+ struct scsi_device *sdev = cmd->device;
+ struct Scsi_Host *shost = sdev->host;
+ unsigned long flags;
+
+ if (shost->use_cmd_list) {
+ spin_lock_irqsave(&sdev->list_lock, flags);
+ list_add_tail(&cmd->list, &sdev->cmd_list);
+ spin_unlock_irqrestore(&sdev->list_lock, flags);
+ }
+ }
+
+ /* Remove a command from the list used by the aacraid and dpt_i2o drivers */
+ void scsi_del_cmd_from_list(struct scsi_cmnd *cmd)
+ {
+ struct scsi_device *sdev = cmd->device;
+ struct Scsi_Host *shost = sdev->host;
+ unsigned long flags;
+
+ if (shost->use_cmd_list) {
+ spin_lock_irqsave(&sdev->list_lock, flags);
+ BUG_ON(list_empty(&cmd->list));
+ list_del_init(&cmd->list);
+ spin_unlock_irqrestore(&sdev->list_lock, flags);
+ }
+ }
+
+/* Called after a request has been started. */
void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd)
{
void *buf = cmd->sense_buffer;
* request queue.
*/
if (q->mq_ops) {
- if (wait)
- blk_mq_quiesce_queue(q);
- else
- blk_mq_quiesce_queue_nowait(q);
- blk_mq_stop_hw_queues(q);
++ blk_mq_quiesce_queue_nowait(q);
} else {
spin_lock_irqsave(q->queue_lock, flags);
blk_stop_queue(q);
return 0;
}
- EXPORT_SYMBOL_GPL(scsi_internal_device_block);
-
+ EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait);
+
/**
- * scsi_internal_device_unblock - resume a device after a block request
- * @sdev: device to resume
- * @new_state: state to set devices to after unblocking
+ * scsi_internal_device_block - try to transition to the SDEV_BLOCK state
+ * @sdev: device to block
+ *
+ * Pause SCSI command processing on the specified device and wait until all
+ * ongoing scsi_request_fn() / scsi_queue_rq() calls have finished. May sleep.
*
- * Called by scsi lld's or the midlayer to restart the device queue
- * for the previously suspended scsi device. Called from interrupt or
- * normal process context.
+ * Returns zero if successful or a negative error code upon failure.
*
- * Returns zero if successful or error if not.
+ * Note:
+ * This routine transitions the device to the SDEV_BLOCK state (which must be
+ * a legal transition). When the device is in this state, command processing
+ * is paused until the device leaves the SDEV_BLOCK state. See also
+ * scsi_internal_device_unblock().
*
- * Notes:
- * This routine transitions the device to the SDEV_RUNNING state
- * or to one of the offline states (which must be a legal transition)
- * allowing the midlayer to goose the queue for this device.
+ * To do: avoid that scsi_send_eh_cmnd() calls queuecommand() after
+ * scsi_internal_device_block() has blocked a SCSI device and also
+ * remove the rport mutex lock and unlock calls from srp_queuecommand().
*/
- int
- scsi_internal_device_unblock(struct scsi_device *sdev,
- enum scsi_device_state new_state)
+ static int scsi_internal_device_block(struct scsi_device *sdev)
{
- struct request_queue *q = sdev->request_queue;
+ struct request_queue *q = sdev->request_queue;
+ int err;
+
+ mutex_lock(&sdev->state_mutex);
+ err = scsi_internal_device_block_nowait(sdev);
+ if (err == 0) {
+ if (q->mq_ops)
+ blk_mq_quiesce_queue(q);
+ else
+ scsi_wait_for_queuecommand(sdev);
+ }
+ mutex_unlock(&sdev->state_mutex);
+
+ return err;
+ }
+
+ void scsi_start_queue(struct scsi_device *sdev)
+ {
+ struct request_queue *q = sdev->request_queue;
unsigned long flags;
- blk_mq_start_stopped_hw_queues(q, false);
+ if (q->mq_ops) {
++ blk_mq_unquiesce_queue(q);
+ } else {
+ spin_lock_irqsave(q->queue_lock, flags);
+ blk_start_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+ }
+ }
+
+ /**
+ * scsi_internal_device_unblock_nowait - resume a device after a block request
+ * @sdev: device to resume
+ * @new_state: state to set the device to after unblocking
+ *
+ * Restart the device queue for a previously suspended SCSI device. Does not
+ * sleep.
+ *
+ * Returns zero if successful or a negative error code upon failure.
+ *
+ * Notes:
+ * This routine transitions the device to the SDEV_RUNNING state or to one of
+ * the offline states (which must be a legal transition) allowing the midlayer
+ * to goose the queue for this device.
+ */
+ int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
+ enum scsi_device_state new_state)
+ {
/*
* Try to transition the scsi device to SDEV_RUNNING or one of the
* offlined states and goose the device queue if successful.
* port is no longer part of the topology. Note: Although a port
* may no longer be part of the topology, it may persist in the remote
* ports displayed by the fc_host. We do this under 2 conditions:
+ *
* 1) If the port was a scsi target, we delay its deletion by "blocking" it.
- * This allows the port to temporarily disappear, then reappear without
- * disrupting the SCSI device tree attached to it. During the "blocked"
- * period the port will still exist.
+ * This allows the port to temporarily disappear, then reappear without
+ * disrupting the SCSI device tree attached to it. During the "blocked"
+ * period the port will still exist.
+ *
* 2) If the port was a scsi target and disappears for longer than we
- * expect, we'll delete the port and the tear down the SCSI device tree
- * attached to it. However, we want to semi-persist the target id assigned
- * to that port if it eventually does exist. The port structure will
- * remain (although with minimal information) so that the target id
- * bindings also remain.
+ * expect, we'll delete the port and the tear down the SCSI device tree
+ * attached to it. However, we want to semi-persist the target id assigned
+ * to that port if it eventually does exist. The port structure will
+ * remain (although with minimal information) so that the target id
- * bindings remails.
++ * bindings also remain.
*
* If the remote port is not an FCP Target, it will be fully torn down
* and deallocated, including the fc_remote_port class device.
projects / karo-tx-linux.git / commitdiff