drivers/scsi/scsi_pm.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  *	scsi_pm.c	Copyright (C) 2010 Alan Stern
  *
  *	SCSI dynamic Power Management
  *		Initial version: Alan Stern <stern@rowland.harvard.edu>
  */

 #include <linux/pm_runtime.h>
 #include <linux/export.h>
 #include <linux/async.h>
 #include <linux/blk-pm.h>

 #include <scsi/scsi.h>
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_driver.h>
 #include <scsi/scsi_host.h>

 #include "scsi_priv.h"

 #ifdef CONFIG_PM_SLEEP

 static int do_scsi_suspend(struct device *dev, const struct dev_pm_ops *pm)
 {
 	return pm && pm->suspend ? pm->suspend(dev) : 0;
 }

 static int do_scsi_freeze(struct device *dev, const struct dev_pm_ops *pm)
 {
 	return pm && pm->freeze ? pm->freeze(dev) : 0;
 }

 static int do_scsi_poweroff(struct device *dev, const struct dev_pm_ops *pm)
 {
 	return pm && pm->poweroff ? pm->poweroff(dev) : 0;
 }

 static int do_scsi_resume(struct device *dev, const struct dev_pm_ops *pm)
 {
 	return pm && pm->resume ? pm->resume(dev) : 0;
 }

 static int do_scsi_thaw(struct device *dev, const struct dev_pm_ops *pm)
 {
 	return pm && pm->thaw ? pm->thaw(dev) : 0;
 }

 static int do_scsi_restore(struct device *dev, const struct dev_pm_ops *pm)
 {
 	return pm && pm->restore ? pm->restore(dev) : 0;
 }

 static int scsi_dev_type_suspend(struct device *dev,
 		int (*cb)(struct device *, const struct dev_pm_ops *))
 {
 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
 	int err;

 	/* flush pending in-flight resume operations, suspend is synchronous */
 	async_synchronize_full_domain(&scsi_sd_pm_domain);

 	err = scsi_device_quiesce(to_scsi_device(dev));
 	if (err == 0) {
 		err = cb(dev, pm);
 		if (err)
 			scsi_device_resume(to_scsi_device(dev));
 	}
 	dev_dbg(dev, "scsi suspend: %d\n", err);
 	return err;
 }

 static int scsi_dev_type_resume(struct device *dev,
 		int (*cb)(struct device *, const struct dev_pm_ops *))
 {
 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
 	int err = 0;

 	err = cb(dev, pm);
 	scsi_device_resume(to_scsi_device(dev));
 	dev_dbg(dev, "scsi resume: %d\n", err);

 	if (err == 0) {
 		pm_runtime_disable(dev);
 		err = pm_runtime_set_active(dev);
 		pm_runtime_enable(dev);

 		/*
 		 * Forcibly set runtime PM status of request queue to "active"
 		 * to make sure we can again get requests from the queue
 		 * (see also blk_pm_peek_request()).
 		 *
 		 * The resume hook will correct runtime PM status of the disk.
 		 */
 		if (!err && scsi_is_sdev_device(dev)) {
 			struct scsi_device *sdev = to_scsi_device(dev);

 			blk_set_runtime_active(sdev->request_queue);
 		}
 	}

 	return err;
 }

 static int
 scsi_bus_suspend_common(struct device *dev,
 		int (*cb)(struct device *, const struct dev_pm_ops *))
 {
 	int err = 0;

 	if (scsi_is_sdev_device(dev)) {
 		/*
 		 * All the high-level SCSI drivers that implement runtime
 		 * PM treat runtime suspend, system suspend, and system
 		 * hibernate nearly identically. In all cases the requirements
 		 * for runtime suspension are stricter.
 		 */
 		if (pm_runtime_suspended(dev))
 			return 0;

 		err = scsi_dev_type_suspend(dev, cb);
 	}

 	return err;
 }

 static void async_sdev_resume(void *dev, async_cookie_t cookie)
 {
 	scsi_dev_type_resume(dev, do_scsi_resume);
 }

 static void async_sdev_thaw(void *dev, async_cookie_t cookie)
 {
 	scsi_dev_type_resume(dev, do_scsi_thaw);
 }

 static void async_sdev_restore(void *dev, async_cookie_t cookie)
 {
 	scsi_dev_type_resume(dev, do_scsi_restore);
 }

 static int scsi_bus_resume_common(struct device *dev,
 		int (*cb)(struct device *, const struct dev_pm_ops *))
 {
 	async_func_t fn;

 	if (!scsi_is_sdev_device(dev))
 		fn = NULL;
 	else if (cb == do_scsi_resume)
 		fn = async_sdev_resume;
 	else if (cb == do_scsi_thaw)
 		fn = async_sdev_thaw;
 	else if (cb == do_scsi_restore)
 		fn = async_sdev_restore;
 	else
 		fn = NULL;

 	if (fn) {
 		async_schedule_domain(fn, dev, &scsi_sd_pm_domain);

 		/*
 		 * If a user has disabled async probing a likely reason
 		 * is due to a storage enclosure that does not inject
 		 * staggered spin-ups.  For safety, make resume
 		 * synchronous as well in that case.
 		 */
 		if (strncmp(scsi_scan_type, "async", 5) != 0)
 			async_synchronize_full_domain(&scsi_sd_pm_domain);
 	} else {
 		pm_runtime_disable(dev);
 		pm_runtime_set_active(dev);
 		pm_runtime_enable(dev);
 	}
 	return 0;
 }

 static int scsi_bus_prepare(struct device *dev)
 {
 	if (scsi_is_host_device(dev)) {
 		/* Wait until async scanning is finished */
 		scsi_complete_async_scans();
 	}
 	return 0;
 }

 static int scsi_bus_suspend(struct device *dev)
 {
 	return scsi_bus_suspend_common(dev, do_scsi_suspend);
 }

 static int scsi_bus_resume(struct device *dev)
 {
 	return scsi_bus_resume_common(dev, do_scsi_resume);
 }

 static int scsi_bus_freeze(struct device *dev)
 {
 	return scsi_bus_suspend_common(dev, do_scsi_freeze);
 }

 static int scsi_bus_thaw(struct device *dev)
 {
 	return scsi_bus_resume_common(dev, do_scsi_thaw);
 }

 static int scsi_bus_poweroff(struct device *dev)
 {
 	return scsi_bus_suspend_common(dev, do_scsi_poweroff);
 }

 static int scsi_bus_restore(struct device *dev)
 {
 	return scsi_bus_resume_common(dev, do_scsi_restore);
 }

 #else /* CONFIG_PM_SLEEP */

 #define scsi_bus_prepare		NULL
 #define scsi_bus_suspend		NULL
 #define scsi_bus_resume			NULL
 #define scsi_bus_freeze			NULL
 #define scsi_bus_thaw			NULL
 #define scsi_bus_poweroff		NULL
 #define scsi_bus_restore		NULL

 #endif /* CONFIG_PM_SLEEP */

 static int sdev_runtime_suspend(struct device *dev)
 {
 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
 	struct scsi_device *sdev = to_scsi_device(dev);
 	int err = 0;

 	err = blk_pre_runtime_suspend(sdev->request_queue);
 	if (err)
 		return err;
 	if (pm && pm->runtime_suspend)
 		err = pm->runtime_suspend(dev);
 	blk_post_runtime_suspend(sdev->request_queue, err);

 	return err;
 }

 static int scsi_runtime_suspend(struct device *dev)
 {
 	int err = 0;

 	dev_dbg(dev, "scsi_runtime_suspend\n");
 	if (scsi_is_sdev_device(dev))
 		err = sdev_runtime_suspend(dev);

 	/* Insert hooks here for targets, hosts, and transport classes */

 	return err;
 }

 static int sdev_runtime_resume(struct device *dev)
 {
 	struct scsi_device *sdev = to_scsi_device(dev);
 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
 	int err = 0;

 	blk_pre_runtime_resume(sdev->request_queue);
 	if (pm && pm->runtime_resume)
 		err = pm->runtime_resume(dev);
 	blk_post_runtime_resume(sdev->request_queue, err);

 	return err;
 }

 static int scsi_runtime_resume(struct device *dev)
 {
 	int err = 0;

 	dev_dbg(dev, "scsi_runtime_resume\n");
 	if (scsi_is_sdev_device(dev))
 		err = sdev_runtime_resume(dev);

 	/* Insert hooks here for targets, hosts, and transport classes */

 	return err;
 }

 static int scsi_runtime_idle(struct device *dev)
 {
 	dev_dbg(dev, "scsi_runtime_idle\n");

 	/* Insert hooks here for targets, hosts, and transport classes */

 	if (scsi_is_sdev_device(dev)) {
 		pm_runtime_mark_last_busy(dev);
 		pm_runtime_autosuspend(dev);
 		return -EBUSY;
 	}

 	return 0;
 }

 int scsi_autopm_get_device(struct scsi_device *sdev)
 {
 	int	err;

 	err = pm_runtime_get_sync(&sdev->sdev_gendev);
 	if (err < 0 && err !=-EACCES)
 		pm_runtime_put_sync(&sdev->sdev_gendev);
 	else
 		err = 0;
 	return err;
 }
 EXPORT_SYMBOL_GPL(scsi_autopm_get_device);

 void scsi_autopm_put_device(struct scsi_device *sdev)
 {
 	pm_runtime_put_sync(&sdev->sdev_gendev);
 }
 EXPORT_SYMBOL_GPL(scsi_autopm_put_device);

 void scsi_autopm_get_target(struct scsi_target *starget)
 {
 	pm_runtime_get_sync(&starget->dev);
 }

 void scsi_autopm_put_target(struct scsi_target *starget)
 {
 	pm_runtime_put_sync(&starget->dev);
 }

 int scsi_autopm_get_host(struct Scsi_Host *shost)
 {
 	int	err;

 	err = pm_runtime_get_sync(&shost->shost_gendev);
 	if (err < 0 && err !=-EACCES)
 		pm_runtime_put_sync(&shost->shost_gendev);
 	else
 		err = 0;
 	return err;
 }

 void scsi_autopm_put_host(struct Scsi_Host *shost)
 {
 	pm_runtime_put_sync(&shost->shost_gendev);
 }

 const struct dev_pm_ops scsi_bus_pm_ops = {
 	.prepare =		scsi_bus_prepare,
 	.suspend =		scsi_bus_suspend,
 	.resume =		scsi_bus_resume,
 	.freeze =		scsi_bus_freeze,
 	.thaw =			scsi_bus_thaw,
 	.poweroff =		scsi_bus_poweroff,
 	.restore =		scsi_bus_restore,
 	.runtime_suspend =	scsi_runtime_suspend,
 	.runtime_resume =	scsi_runtime_resume,
 	.runtime_idle =		scsi_runtime_idle,
 };
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* scsi_pm.c Copyright (C) 2010 Alan Stern
	*
	* SCSI dynamic Power Management
	* Initial version: Alan Stern <stern@rowland.harvard.edu>
	*/

	#include <linux/pm_runtime.h>
	#include <linux/export.h>
	#include <linux/async.h>
	#include <linux/blk-pm.h>

	#include <scsi/scsi.h>
	#include <scsi/scsi_device.h>
	#include <scsi/scsi_driver.h>
	#include <scsi/scsi_host.h>

	#include "scsi_priv.h"

	#ifdef CONFIG_PM_SLEEP

	static int do_scsi_suspend(struct device dev, const struct dev_pm_ops pm)
	{
	return pm && pm->suspend ? pm->suspend(dev) : 0;
	}

	static int do_scsi_freeze(struct device dev, const struct dev_pm_ops pm)
	{
	return pm && pm->freeze ? pm->freeze(dev) : 0;
	}

	static int do_scsi_poweroff(struct device dev, const struct dev_pm_ops pm)
	{
	return pm && pm->poweroff ? pm->poweroff(dev) : 0;
	}

	static int do_scsi_resume(struct device dev, const struct dev_pm_ops pm)
	{
	return pm && pm->resume ? pm->resume(dev) : 0;
	}

	static int do_scsi_thaw(struct device dev, const struct dev_pm_ops pm)
	{
	return pm && pm->thaw ? pm->thaw(dev) : 0;
	}

	static int do_scsi_restore(struct device dev, const struct dev_pm_ops pm)
	{
	return pm && pm->restore ? pm->restore(dev) : 0;
	}

	static int scsi_dev_type_suspend(struct device *dev,
	int (cb)(struct device , const struct dev_pm_ops *))
	{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	int err;

	/* flush pending in-flight resume operations, suspend is synchronous */
	async_synchronize_full_domain(&scsi_sd_pm_domain);

	err = scsi_device_quiesce(to_scsi_device(dev));
	if (err == 0) {
	err = cb(dev, pm);
	if (err)
	scsi_device_resume(to_scsi_device(dev));
	}
	dev_dbg(dev, "scsi suspend: %d\n", err);
	return err;
	}

	static int scsi_dev_type_resume(struct device *dev,
	int (cb)(struct device , const struct dev_pm_ops *))
	{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	int err = 0;

	err = cb(dev, pm);
	scsi_device_resume(to_scsi_device(dev));
	dev_dbg(dev, "scsi resume: %d\n", err);

	if (err == 0) {
	pm_runtime_disable(dev);
	err = pm_runtime_set_active(dev);
	pm_runtime_enable(dev);

	/*
	* Forcibly set runtime PM status of request queue to "active"
	* to make sure we can again get requests from the queue
	* (see also blk_pm_peek_request()).
	*
	* The resume hook will correct runtime PM status of the disk.
	*/
	if (!err && scsi_is_sdev_device(dev)) {
	struct scsi_device *sdev = to_scsi_device(dev);

	blk_set_runtime_active(sdev->request_queue);
	}
	}

	return err;
	}

	static int
	scsi_bus_suspend_common(struct device *dev,
	int (cb)(struct device , const struct dev_pm_ops *))
	{
	int err = 0;

	if (scsi_is_sdev_device(dev)) {
	/*
	* All the high-level SCSI drivers that implement runtime
	* PM treat runtime suspend, system suspend, and system
	* hibernate nearly identically. In all cases the requirements
	* for runtime suspension are stricter.
	*/
	if (pm_runtime_suspended(dev))
	return 0;

	err = scsi_dev_type_suspend(dev, cb);
	}

	return err;
	}

	static void async_sdev_resume(void *dev, async_cookie_t cookie)
	{
	scsi_dev_type_resume(dev, do_scsi_resume);
	}

	static void async_sdev_thaw(void *dev, async_cookie_t cookie)
	{
	scsi_dev_type_resume(dev, do_scsi_thaw);
	}

	static void async_sdev_restore(void *dev, async_cookie_t cookie)
	{
	scsi_dev_type_resume(dev, do_scsi_restore);
	}

	static int scsi_bus_resume_common(struct device *dev,
	int (cb)(struct device , const struct dev_pm_ops *))
	{
	async_func_t fn;

	if (!scsi_is_sdev_device(dev))
	fn = NULL;
	else if (cb == do_scsi_resume)
	fn = async_sdev_resume;
	else if (cb == do_scsi_thaw)
	fn = async_sdev_thaw;
	else if (cb == do_scsi_restore)
	fn = async_sdev_restore;
	else
	fn = NULL;

	if (fn) {
	async_schedule_domain(fn, dev, &scsi_sd_pm_domain);

	/*
	* If a user has disabled async probing a likely reason
	* is due to a storage enclosure that does not inject
	* staggered spin-ups. For safety, make resume
	* synchronous as well in that case.
	*/
	if (strncmp(scsi_scan_type, "async", 5) != 0)
	async_synchronize_full_domain(&scsi_sd_pm_domain);
	} else {
	pm_runtime_disable(dev);
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);
	}
	return 0;
	}

	static int scsi_bus_prepare(struct device *dev)
	{
	if (scsi_is_host_device(dev)) {
	/* Wait until async scanning is finished */
	scsi_complete_async_scans();
	}
	return 0;
	}

	static int scsi_bus_suspend(struct device *dev)
	{
	return scsi_bus_suspend_common(dev, do_scsi_suspend);
	}

	static int scsi_bus_resume(struct device *dev)
	{
	return scsi_bus_resume_common(dev, do_scsi_resume);
	}

	static int scsi_bus_freeze(struct device *dev)
	{
	return scsi_bus_suspend_common(dev, do_scsi_freeze);
	}

	static int scsi_bus_thaw(struct device *dev)
	{
	return scsi_bus_resume_common(dev, do_scsi_thaw);
	}

	static int scsi_bus_poweroff(struct device *dev)
	{
	return scsi_bus_suspend_common(dev, do_scsi_poweroff);
	}

	static int scsi_bus_restore(struct device *dev)
	{
	return scsi_bus_resume_common(dev, do_scsi_restore);
	}

	#else /* CONFIG_PM_SLEEP */

	#define scsi_bus_prepare NULL
	#define scsi_bus_suspend NULL
	#define scsi_bus_resume NULL
	#define scsi_bus_freeze NULL
	#define scsi_bus_thaw NULL
	#define scsi_bus_poweroff NULL
	#define scsi_bus_restore NULL

	#endif /* CONFIG_PM_SLEEP */

	static int sdev_runtime_suspend(struct device *dev)
	{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	struct scsi_device *sdev = to_scsi_device(dev);
	int err = 0;

	err = blk_pre_runtime_suspend(sdev->request_queue);
	if (err)
	return err;
	if (pm && pm->runtime_suspend)
	err = pm->runtime_suspend(dev);
	blk_post_runtime_suspend(sdev->request_queue, err);

	return err;
	}

	static int scsi_runtime_suspend(struct device *dev)
	{
	int err = 0;

	dev_dbg(dev, "scsi_runtime_suspend\n");
	if (scsi_is_sdev_device(dev))
	err = sdev_runtime_suspend(dev);

	/* Insert hooks here for targets, hosts, and transport classes */

	return err;
	}

	static int sdev_runtime_resume(struct device *dev)
	{
	struct scsi_device *sdev = to_scsi_device(dev);
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	int err = 0;

	blk_pre_runtime_resume(sdev->request_queue);
	if (pm && pm->runtime_resume)
	err = pm->runtime_resume(dev);
	blk_post_runtime_resume(sdev->request_queue, err);

	return err;
	}

	static int scsi_runtime_resume(struct device *dev)
	{
	int err = 0;

	dev_dbg(dev, "scsi_runtime_resume\n");
	if (scsi_is_sdev_device(dev))
	err = sdev_runtime_resume(dev);

	/* Insert hooks here for targets, hosts, and transport classes */

	return err;
	}

	static int scsi_runtime_idle(struct device *dev)
	{
	dev_dbg(dev, "scsi_runtime_idle\n");

	/* Insert hooks here for targets, hosts, and transport classes */

	if (scsi_is_sdev_device(dev)) {
	pm_runtime_mark_last_busy(dev);
	pm_runtime_autosuspend(dev);
	return -EBUSY;
	}

	return 0;
	}

	int scsi_autopm_get_device(struct scsi_device *sdev)
	{
	int err;

	err = pm_runtime_get_sync(&sdev->sdev_gendev);
	if (err < 0 && err !=-EACCES)
	pm_runtime_put_sync(&sdev->sdev_gendev);
	else
	err = 0;
	return err;
	}
	EXPORT_SYMBOL_GPL(scsi_autopm_get_device);

	void scsi_autopm_put_device(struct scsi_device *sdev)
	{
	pm_runtime_put_sync(&sdev->sdev_gendev);
	}
	EXPORT_SYMBOL_GPL(scsi_autopm_put_device);

	void scsi_autopm_get_target(struct scsi_target *starget)
	{
	pm_runtime_get_sync(&starget->dev);
	}

	void scsi_autopm_put_target(struct scsi_target *starget)
	{
	pm_runtime_put_sync(&starget->dev);
	}

	int scsi_autopm_get_host(struct Scsi_Host *shost)
	{
	int err;

	err = pm_runtime_get_sync(&shost->shost_gendev);
	if (err < 0 && err !=-EACCES)
	pm_runtime_put_sync(&shost->shost_gendev);
	else
	err = 0;
	return err;
	}

	void scsi_autopm_put_host(struct Scsi_Host *shost)
	{
	pm_runtime_put_sync(&shost->shost_gendev);
	}

	const struct dev_pm_ops scsi_bus_pm_ops = {
	.prepare = scsi_bus_prepare,
	.suspend = scsi_bus_suspend,
	.resume = scsi_bus_resume,
	.freeze = scsi_bus_freeze,
	.thaw = scsi_bus_thaw,
	.poweroff = scsi_bus_poweroff,
	.restore = scsi_bus_restore,
	.runtime_suspend = scsi_runtime_suspend,
	.runtime_resume = scsi_runtime_resume,
	.runtime_idle = scsi_runtime_idle,
	};