1 // SPDX-License-Identifier: GPL-2.0
3 #include <linux/blk-mq.h>
4 #include <linux/blk-pm.h>
7 #include "blk-mq.h"
8 #include "blk-mq-tag.h"
11  * blk_pm_runtime_init - Block layer runtime PM initialization routine
16  *    Initialize runtime-PM-related fields for @q and start auto suspend for
17  *    @dev. Drivers that want to take advantage of request-based runtime PM
24  *    the autosuspend delay is set to -1 to make runtime suspend impossible
33 	q->dev = dev;  in blk_pm_runtime_init()
34 	q->rpm_status = RPM_ACTIVE;  in blk_pm_runtime_init()
35 	pm_runtime_set_autosuspend_delay(q->dev, -1);  in blk_pm_runtime_init()
36 	pm_runtime_use_autosuspend(q->dev);  in blk_pm_runtime_init()
41  * blk_pre_runtime_suspend - Pre runtime suspend check
58  *    0		- OK to runtime suspend the device
59  *    -EBUSY	- Device should not be runtime suspended
65 	if (!q->dev)  in blk_pre_runtime_suspend()
68 	WARN_ON_ONCE(q->rpm_status != RPM_ACTIVE);  in blk_pre_runtime_suspend()
70 	spin_lock_irq(&q->queue_lock);  in blk_pre_runtime_suspend()
71 	q->rpm_status = RPM_SUSPENDING;  in blk_pre_runtime_suspend()
72 	spin_unlock_irq(&q->queue_lock);  in blk_pre_runtime_suspend()
76 	 * non-PM blk_queue_enter() calls are in progress to avoid that any  in blk_pre_runtime_suspend()
77 	 * new non-PM blk_queue_enter() calls succeed before the pm_only  in blk_pre_runtime_suspend()
81 	ret = -EBUSY;  in blk_pre_runtime_suspend()
82 	/* Switch q_usage_counter from per-cpu to atomic mode. */  in blk_pre_runtime_suspend()
87 	 * blk_queue_enter() calls see the pm-only state. See also  in blk_pre_runtime_suspend()
90 	percpu_ref_switch_to_atomic_sync(&q->q_usage_counter);  in blk_pre_runtime_suspend()
91 	if (percpu_ref_is_zero(&q->q_usage_counter))  in blk_pre_runtime_suspend()
93 	/* Switch q_usage_counter back to per-cpu mode. */  in blk_pre_runtime_suspend()
97 		spin_lock_irq(&q->queue_lock);  in blk_pre_runtime_suspend()
98 		q->rpm_status = RPM_ACTIVE;  in blk_pre_runtime_suspend()
99 		pm_runtime_mark_last_busy(q->dev);  in blk_pre_runtime_suspend()
100 		spin_unlock_irq(&q->queue_lock);  in blk_pre_runtime_suspend()
110  * blk_post_runtime_suspend - Post runtime suspend processing
124 	if (!q->dev)  in blk_post_runtime_suspend()
127 	spin_lock_irq(&q->queue_lock);  in blk_post_runtime_suspend()
129 		q->rpm_status = RPM_SUSPENDED;  in blk_post_runtime_suspend()
131 		q->rpm_status = RPM_ACTIVE;  in blk_post_runtime_suspend()
132 		pm_runtime_mark_last_busy(q->dev);  in blk_post_runtime_suspend()
134 	spin_unlock_irq(&q->queue_lock);  in blk_post_runtime_suspend()
142  * blk_pre_runtime_resume - Pre runtime resume processing
154 	if (!q->dev)  in blk_pre_runtime_resume()
157 	spin_lock_irq(&q->queue_lock);  in blk_pre_runtime_resume()
158 	q->rpm_status = RPM_RESUMING;  in blk_pre_runtime_resume()
159 	spin_unlock_irq(&q->queue_lock);  in blk_pre_runtime_resume()
164  * blk_post_runtime_resume - Post runtime resume processing
170  *    whether the device's runtime-resume succeeded; even if it failed the
183  * blk_set_runtime_active - Force runtime status of the queue to be active
189  * which is still "suspended". This prevents processing requests from the
193  * runtime PM status and re-enable peeking requests from the queue. It
203 	if (!q->dev)  in blk_set_runtime_active()
206 	spin_lock_irq(&q->queue_lock);  in blk_set_runtime_active()
207 	old_status = q->rpm_status;  in blk_set_runtime_active()
208 	q->rpm_status = RPM_ACTIVE;  in blk_set_runtime_active()
209 	pm_runtime_mark_last_busy(q->dev);  in blk_set_runtime_active()
210 	pm_request_autosuspend(q->dev);  in blk_set_runtime_active()
211 	spin_unlock_irq(&q->queue_lock);  in blk_set_runtime_active()