diff options
| -rw-r--r-- | block/blk-sysfs.c | 16 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 3 |
2 files changed, 13 insertions, 6 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 223da196a548..d584461a1d84 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -93,9 +93,9 @@ static ssize_t queue_ra_show(struct gendisk *disk, char *page) { ssize_t ret; - mutex_lock(&disk->queue->sysfs_lock); + mutex_lock(&disk->queue->limits_lock); ret = queue_var_show(disk->bdi->ra_pages << (PAGE_SHIFT - 10), page); - mutex_unlock(&disk->queue->sysfs_lock); + mutex_unlock(&disk->queue->limits_lock); return ret; } @@ -111,12 +111,15 @@ queue_ra_store(struct gendisk *disk, const char *page, size_t count) ret = queue_var_store(&ra_kb, page, count); if (ret < 0) return ret; - - mutex_lock(&q->sysfs_lock); + /* + * ->ra_pages is protected by ->limits_lock because it is usually + * calculated from the queue limits by queue_limits_commit_update. + */ + mutex_lock(&q->limits_lock); memflags = blk_mq_freeze_queue(q); disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); + mutex_unlock(&q->limits_lock); blk_mq_unfreeze_queue(q, memflags); - mutex_unlock(&q->sysfs_lock); return ret; } @@ -670,7 +673,8 @@ static struct attribute *queue_attrs[] = { &queue_dma_alignment_entry.attr, /* - * Attributes which are protected with q->sysfs_lock. + * Attributes which require some form of locking other than + * q->sysfs_lock. */ &queue_ra_entry.attr, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 0ee3b5c9388e..3bee1b4858b6 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -571,6 +571,9 @@ struct request_queue { struct mutex elevator_lock; struct mutex sysfs_lock; + /* + * Protects queue limits and also sysfs attribute read_ahead_kb. + */ struct mutex limits_lock; /* |