diff options
Diffstat (limited to 'include/linux/blkdev.h')
| -rw-r--r-- | include/linux/blkdev.h | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index d37751789bf5..e39c45bc0a97 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -268,10 +268,16 @@ static inline dev_t disk_devt(struct gendisk *disk) return MKDEV(disk->major, disk->first_minor); } +/* + * We should strive for 1 << (PAGE_SHIFT + MAX_PAGECACHE_ORDER) + * however we constrain this to what we can validate and test. + */ +#define BLK_MAX_BLOCK_SIZE SZ_64K + /* blk_validate_limits() validates bsize, so drivers don't usually need to */ static inline int blk_validate_block_size(unsigned long bsize) { - if (bsize < 512 || bsize > PAGE_SIZE || !is_power_of_2(bsize)) + if (bsize < 512 || bsize > BLK_MAX_BLOCK_SIZE || !is_power_of_2(bsize)) return -EINVAL; return 0; @@ -562,7 +568,22 @@ struct request_queue { struct blk_flush_queue *fq; struct list_head flush_list; + /* + * Protects against I/O scheduler switching, particularly when updating + * q->elevator. Since the elevator update code path may also modify q-> + * nr_requests and wbt latency, this lock also protects the sysfs attrs + * nr_requests and wbt_lat_usec. Additionally the nr_hw_queues update + * may modify hctx tags, reserved-tags and cpumask, so this lock also + * helps protect the hctx sysfs/debugfs attrs. To ensure proper locking + * order during an elevator or nr_hw_queue update, first freeze the + * queue, then acquire ->elevator_lock. + */ + struct mutex elevator_lock; + struct mutex sysfs_lock; + /* + * Protects queue limits and also sysfs attribute read_ahead_kb. + */ struct mutex limits_lock; /* |