diff options
Diffstat (limited to 'block/blk-sysfs.c')
| -rw-r--r-- | block/blk-sysfs.c | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 76c47fe9b8d6..8684c57498cc 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -143,21 +143,22 @@ queue_ra_store(struct gendisk *disk, const char *page, size_t count) { unsigned long ra_kb; ssize_t ret; - unsigned int memflags; struct request_queue *q = disk->queue; ret = queue_var_store(&ra_kb, page, count); if (ret < 0) return ret; /* - * ->ra_pages is protected by ->limits_lock because it is usually - * calculated from the queue limits by queue_limits_commit_update. + * The ->ra_pages change below is protected by ->limits_lock because it + * is usually calculated from the queue limits by + * queue_limits_commit_update(). + * + * bdi->ra_pages reads are not serialized against bdi->ra_pages writes. + * Use WRITE_ONCE() to write bdi->ra_pages once. */ mutex_lock(&q->limits_lock); - memflags = blk_mq_freeze_queue(q); - disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10); + WRITE_ONCE(disk->bdi->ra_pages, ra_kb >> (PAGE_SHIFT - 10)); mutex_unlock(&q->limits_lock); - blk_mq_unfreeze_queue(q, memflags); return ret; } @@ -375,21 +376,18 @@ static ssize_t queue_nomerges_store(struct gendisk *disk, const char *page, size_t count) { unsigned long nm; - unsigned int memflags; struct request_queue *q = disk->queue; ssize_t ret = queue_var_store(&nm, page, count); if (ret < 0) return ret; - memflags = blk_mq_freeze_queue(q); blk_queue_flag_clear(QUEUE_FLAG_NOMERGES, q); blk_queue_flag_clear(QUEUE_FLAG_NOXMERGES, q); if (nm == 2) blk_queue_flag_set(QUEUE_FLAG_NOMERGES, q); else if (nm) blk_queue_flag_set(QUEUE_FLAG_NOXMERGES, q); - blk_mq_unfreeze_queue(q, memflags); return ret; } @@ -409,7 +407,6 @@ queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count) #ifdef CONFIG_SMP struct request_queue *q = disk->queue; unsigned long val; - unsigned int memflags; ret = queue_var_store(&val, page, count); if (ret < 0) @@ -421,7 +418,6 @@ queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count) * are accessed individually using atomic test_bit operation. So we * don't grab any lock while updating these flags. */ - memflags = blk_mq_freeze_queue(q); if (val == 2) { blk_queue_flag_set(QUEUE_FLAG_SAME_COMP, q); blk_queue_flag_set(QUEUE_FLAG_SAME_FORCE, q); @@ -432,7 +428,6 @@ queue_rq_affinity_store(struct gendisk *disk, const char *page, size_t count) blk_queue_flag_clear(QUEUE_FLAG_SAME_COMP, q); blk_queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q); } - blk_mq_unfreeze_queue(q, memflags); #endif return ret; } @@ -446,11 +441,9 @@ static ssize_t queue_poll_delay_store(struct gendisk *disk, const char *page, static ssize_t queue_poll_store(struct gendisk *disk, const char *page, size_t count) { - unsigned int memflags; ssize_t ret = count; struct request_queue *q = disk->queue; - memflags = blk_mq_freeze_queue(q); if (!(q->limits.features & BLK_FEAT_POLL)) { ret = -EINVAL; goto out; @@ -459,7 +452,6 @@ static ssize_t queue_poll_store(struct gendisk *disk, const char *page, pr_info_ratelimited("writes to the poll attribute are ignored.\n"); pr_info_ratelimited("please use driver specific parameters instead.\n"); out: - blk_mq_unfreeze_queue(q, memflags); return ret; } @@ -472,7 +464,7 @@ static ssize_t queue_io_timeout_show(struct gendisk *disk, char *page) static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page, size_t count) { - unsigned int val, memflags; + unsigned int val; int err; struct request_queue *q = disk->queue; @@ -480,9 +472,7 @@ static ssize_t queue_io_timeout_store(struct gendisk *disk, const char *page, if (err || val == 0) return -EINVAL; - memflags = blk_mq_freeze_queue(q); blk_queue_rq_timeout(q, msecs_to_jiffies(val)); - blk_mq_unfreeze_queue(q, memflags); return count; } |