From: Yu Kuai yukuai3@huawei.com
hulk inclusion category: bugfix bugzilla: 173119 CVE: NA
-----------------------------------------------
Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- block/blk-core.c | 17 ++++++++++------- block/blk-mq.c | 24 +++++++++++++++--------- block/blk-sysfs.c | 2 +- block/blk.h | 16 ++++++++++++++++ include/linux/blkdev.h | 12 ++++++------ 5 files changed, 48 insertions(+), 23 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c index b67cb175b9737..7760bebeabcd7 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -955,7 +955,7 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) smp_rmb();
wait_event(q->mq_freeze_wq, - (!q->mq_freeze_depth && + (!queue_to_wrapper(q)->mq_freeze_depth && (pm || !blk_queue_pm_only(q))) || blk_queue_dying(q)); if (blk_queue_dying(q)) @@ -1004,13 +1004,15 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id, spinlock_t *lock) { struct request_queue *q; + struct request_queue_wrapper *q_wrapper; int ret;
- q = kmem_cache_alloc_node(blk_requestq_cachep, - gfp_mask | __GFP_ZERO, node_id); - if (!q) + q_wrapper = kmem_cache_alloc_node(blk_requestq_cachep, + gfp_mask | __GFP_ZERO, node_id); + if (!q_wrapper) return NULL;
+ q = &q_wrapper->q; INIT_LIST_HEAD(&q->queue_head); q->last_merge = NULL; q->end_sector = 0; @@ -1071,7 +1073,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id, queue_flag_set_unlocked(QUEUE_FLAG_BYPASS, q);
init_waitqueue_head(&q->mq_freeze_wq); - mutex_init(&q->mq_freeze_lock); + mutex_init(&q_wrapper->mq_freeze_lock);
/* * Init percpu_ref in atomic mode so that it's faster to shutdown. @@ -1098,7 +1100,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id, fail_id: ida_simple_remove(&blk_queue_ida, q->id); fail_q: - kmem_cache_free(blk_requestq_cachep, q); + kmem_cache_free(blk_requestq_cachep, q_wrapper); return NULL; } EXPORT_SYMBOL(blk_alloc_queue_node); @@ -3961,7 +3963,8 @@ int __init blk_dev_init(void) sizeof(struct request), 0, SLAB_PANIC, NULL);
blk_requestq_cachep = kmem_cache_create("request_queue", - sizeof(struct request_queue), 0, SLAB_PANIC, NULL); + sizeof(struct request_queue_wrapper), 0, SLAB_PANIC, + NULL);
#ifdef CONFIG_DEBUG_FS blk_debugfs_root = debugfs_create_dir("block", NULL); diff --git a/block/blk-mq.c b/block/blk-mq.c index 0de720aa544fa..b6bc8769a6ffa 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -136,14 +136,16 @@ void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
void blk_freeze_queue_start(struct request_queue *q) { - mutex_lock(&q->mq_freeze_lock); - if (++q->mq_freeze_depth == 1) { + struct request_queue_wrapper *q_wrapper = queue_to_wrapper(q); + + mutex_lock(&q_wrapper->mq_freeze_lock); + if (++q_wrapper->mq_freeze_depth == 1) { percpu_ref_kill(&q->q_usage_counter); - mutex_unlock(&q->mq_freeze_lock); + mutex_unlock(&q_wrapper->mq_freeze_lock); if (q->mq_ops) blk_mq_run_hw_queues(q, false); } else { - mutex_unlock(&q->mq_freeze_lock); + mutex_unlock(&q_wrapper->mq_freeze_lock); } } EXPORT_SYMBOL_GPL(blk_freeze_queue_start); @@ -194,14 +196,18 @@ EXPORT_SYMBOL_GPL(blk_mq_freeze_queue);
void blk_mq_unfreeze_queue(struct request_queue *q) { - mutex_lock(&q->mq_freeze_lock); - q->mq_freeze_depth--; - WARN_ON_ONCE(q->mq_freeze_depth < 0); - if (!q->mq_freeze_depth) { + struct request_queue_wrapper *q_wrapper = queue_to_wrapper(q); + + mutex_lock(&q_wrapper->mq_freeze_lock); + q_wrapper->mq_freeze_depth--; + + WARN_ON_ONCE(q_wrapper->mq_freeze_depth < 0); + if (!q_wrapper->mq_freeze_depth) { percpu_ref_reinit(&q->q_usage_counter); wake_up_all(&q->mq_freeze_wq); } - mutex_unlock(&q->mq_freeze_lock); + + mutex_unlock(&q_wrapper->mq_freeze_lock); } EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 2d905a8b14730..a05b2844f01cf 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -792,7 +792,7 @@ static void blk_free_queue_rcu(struct rcu_head *rcu_head) { struct request_queue *q = container_of(rcu_head, struct request_queue, rcu_head); - kmem_cache_free(blk_requestq_cachep, q); + kmem_cache_free(blk_requestq_cachep, queue_to_wrapper(q)); }
/** diff --git a/block/blk.h b/block/blk.h index 1a5b67b57e6b2..8bb450ef6659b 100644 --- a/block/blk.h +++ b/block/blk.h @@ -37,6 +37,22 @@ struct blk_flush_queue { spinlock_t mq_flush_lock; };
+/* + * The wrapper of request_queue to fix kabi while adding members. + */ +struct request_queue_wrapper { + struct request_queue q; + /* + * Protect concurrent access to q_usage_counter by + * percpu_ref_kill() and percpu_ref_reinit(). + */ + struct mutex mq_freeze_lock; + int mq_freeze_depth; +}; + +#define queue_to_wrapper(q) \ + container_of(q, struct request_queue_wrapper, q) + extern struct kmem_cache *blk_requestq_cachep; extern struct kmem_cache *request_cachep; extern struct kobj_type blk_queue_ktype; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index bb0ac8cbbb4c0..d60280e47a2ca 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -655,7 +655,12 @@ struct request_queue { spinlock_t unused_hctx_lock;
int bypass_depth; - int mq_freeze_depth; + /* + * use 'mq_freeze_depth' in request_queue_wrapper instead of here, which + * is protected by 'mq_freeze_lock' in request_queue_wrapper. The reason + * to keep unused 'mq_freeze_depth' here is to avoid kabi broken. + */ + atomic_t mq_freeze_depth;
#if defined(CONFIG_BLK_DEV_BSG) bsg_job_fn *bsg_job_fn; @@ -668,11 +673,6 @@ struct request_queue { #endif struct rcu_head rcu_head; wait_queue_head_t mq_freeze_wq; - /* - * Protect concurrent access to q_usage_counter by - * percpu_ref_kill() and percpu_ref_reinit(). - */ - struct mutex mq_freeze_lock; struct percpu_ref q_usage_counter; struct list_head all_q_node;