diff options
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/blkdev.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 251a11d2d2ae..d41d7fe93457 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -474,6 +474,7 @@ struct request_queue { struct mutex sysfs_lock; struct mutex sysfs_dir_lock; + struct mutex limits_lock; /* * for reusing dead hctx instance in case of updating @@ -862,6 +863,28 @@ static inline unsigned int blk_chunk_sectors_left(sector_t offset, return chunk_sectors - (offset & (chunk_sectors - 1)); } +/** + * queue_limits_start_update - start an atomic update of queue limits + * @q: queue to update + * + * This functions starts an atomic update of the queue limits. It takes a lock + * to prevent other updates and returns a snapshot of the current limits that + * the caller can modify. The caller must call queue_limits_commit_update() + * to finish the update. + * + * Context: process context. The caller must have frozen the queue or ensured + * that there is outstanding I/O by other means. + */ +static inline struct queue_limits +queue_limits_start_update(struct request_queue *q) + __acquires(q->limits_lock) +{ + mutex_lock(&q->limits_lock); + return q->limits; +} +int queue_limits_commit_update(struct request_queue *q, + struct queue_limits *lim); + /* * Access functions for manipulating queue properties */ |