From 6c9546675864f51506af69eca388e5d922942c56 Mon Sep 17 00:00:00 2001 From: Lin Ming Date: Sat, 23 Mar 2013 11:42:26 +0800 Subject: block: add runtime pm helpers Add runtime pm helper functions: void blk_pm_runtime_init(struct request_queue *q, struct device *dev) - Initialization function for drivers to call. int blk_pre_runtime_suspend(struct request_queue *q) - If any requests are in the queue, mark last busy and return -EBUSY. Otherwise set q->rpm_status to RPM_SUSPENDING and return 0. void blk_post_runtime_suspend(struct request_queue *q, int err) - If the suspend succeeded then set q->rpm_status to RPM_SUSPENDED. Otherwise set it to RPM_ACTIVE and mark last busy. void blk_pre_runtime_resume(struct request_queue *q) - Set q->rpm_status to RPM_RESUMING. void blk_post_runtime_resume(struct request_queue *q, int err) - If the resume succeeded then set q->rpm_status to RPM_ACTIVE and call __blk_run_queue, then mark last busy and autosuspend. Otherwise set q->rpm_status to RPM_SUSPENDED. The idea and API is designed by Alan Stern and described here: http://marc.info/?l=linux-scsi&m=133727953625963&w=2 Signed-off-by: Lin Ming Signed-off-by: Aaron Lu Acked-by: Alan Stern Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 78feda9bbae2..89d89c7162aa 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -361,6 +361,12 @@ struct request_queue { */ struct kobject kobj; +#ifdef CONFIG_PM_RUNTIME + struct device *dev; + int rpm_status; + unsigned int nr_pending; +#endif + /* * queue settings */ @@ -960,6 +966,27 @@ struct request_queue *blk_alloc_queue(gfp_t); struct request_queue *blk_alloc_queue_node(gfp_t, int); extern void blk_put_queue(struct request_queue *); +/* + * block layer runtime pm functions + */ +#ifdef CONFIG_PM_RUNTIME +extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); +extern int blk_pre_runtime_suspend(struct request_queue *q); +extern void blk_post_runtime_suspend(struct request_queue *q, int err); +extern void blk_pre_runtime_resume(struct request_queue *q); +extern void blk_post_runtime_resume(struct request_queue *q, int err); +#else +static inline void blk_pm_runtime_init(struct request_queue *q, + struct device *dev) {} +static inline int blk_pre_runtime_suspend(struct request_queue *q) +{ + return -ENOSYS; +} +static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} +static inline void blk_pre_runtime_resume(struct request_queue *q) {} +static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} +#endif + /* * blk_plug permits building a queue of related requests by holding the I/O * fragments for a short period. This allows merging of sequential requests -- cgit v1.2.3