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| author |   Lin Ming <ming.m.lin@intel.com> | 2013-03-23 11:42:26 +0800 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2013-03-22 22:22:15 -0600 |
| commit | 6c9546675864f51506af69eca388e5d922942c56 (patch) | |
| tree | e689048677a1a066960ffd7ebd8330632476c045 /include/linux/blkdev.h | |
| parent | block: add a flag to identify PM request (diff) | |
| download | linux-dev-6c9546675864f51506af69eca388e5d922942c56.tar.xz linux-dev-6c9546675864f51506af69eca388e5d922942c56.zip | |
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 <ming.m.lin@intel.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux/blkdev.h')
| -rw-r--r-- | include/linux/blkdev.h | 27 |
1 files changed, 27 insertions, 0 deletions
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 */ @@ -961,6 +967,27 @@ 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 * into single larger request. As the requests are moved from a per-task list to |