diff options
Diffstat (limited to 'drivers/block/rbd.c')
| -rw-r--r-- | drivers/block/rbd.c | 104 |
1 files changed, 90 insertions, 14 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 4ae1cdf40b27..a1bb8f3100a8 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -331,6 +331,7 @@ struct rbd_img_request { struct rbd_obj_request *obj_request; /* obj req initiator */ }; + struct list_head lock_item; struct list_head object_extents; /* obj_req.ex structs */ struct mutex state_mutex; @@ -410,6 +411,9 @@ struct rbd_device { struct work_struct released_lock_work; struct delayed_work lock_dwork; struct work_struct unlock_work; + spinlock_t lock_lists_lock; + struct list_head running_list; + struct completion releasing_wait; wait_queue_head_t lock_waitq; struct workqueue_struct *task_wq; @@ -1726,6 +1730,7 @@ static struct rbd_img_request *rbd_img_request_create( if (rbd_dev_parent_get(rbd_dev)) img_request_layered_set(img_request); + INIT_LIST_HEAD(&img_request->lock_item); INIT_LIST_HEAD(&img_request->object_extents); mutex_init(&img_request->state_mutex); kref_init(&img_request->kref); @@ -1745,6 +1750,7 @@ static void rbd_img_request_destroy(struct kref *kref) dout("%s: img %p\n", __func__, img_request); + WARN_ON(!list_empty(&img_request->lock_item)); for_each_obj_request_safe(img_request, obj_request, next_obj_request) rbd_img_obj_request_del(img_request, obj_request); @@ -2872,6 +2878,50 @@ static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result) rbd_img_handle_request(obj_req->img_request, result); } +static bool need_exclusive_lock(struct rbd_img_request *img_req) +{ + struct rbd_device *rbd_dev = img_req->rbd_dev; + + if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) + return false; + + if (rbd_dev->spec->snap_id != CEPH_NOSNAP) + return false; + + rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags)); + if (rbd_dev->opts->lock_on_read) + return true; + + return rbd_img_is_write(img_req); +} + +static void rbd_lock_add_request(struct rbd_img_request *img_req) +{ + struct rbd_device *rbd_dev = img_req->rbd_dev; + + lockdep_assert_held(&rbd_dev->lock_rwsem); + spin_lock(&rbd_dev->lock_lists_lock); + rbd_assert(list_empty(&img_req->lock_item)); + list_add_tail(&img_req->lock_item, &rbd_dev->running_list); + spin_unlock(&rbd_dev->lock_lists_lock); +} + +static void rbd_lock_del_request(struct rbd_img_request *img_req) +{ + struct rbd_device *rbd_dev = img_req->rbd_dev; + bool need_wakeup; + + lockdep_assert_held(&rbd_dev->lock_rwsem); + spin_lock(&rbd_dev->lock_lists_lock); + rbd_assert(!list_empty(&img_req->lock_item)); + list_del_init(&img_req->lock_item); + need_wakeup = (rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING && + list_empty(&rbd_dev->running_list)); + spin_unlock(&rbd_dev->lock_lists_lock); + if (need_wakeup) + complete(&rbd_dev->releasing_wait); +} + static void rbd_img_object_requests(struct rbd_img_request *img_req) { struct rbd_obj_request *obj_req; @@ -2927,9 +2977,19 @@ static bool __rbd_img_handle_request(struct rbd_img_request *img_req, struct rbd_device *rbd_dev = img_req->rbd_dev; bool done; - mutex_lock(&img_req->state_mutex); - done = rbd_img_advance(img_req, result); - mutex_unlock(&img_req->state_mutex); + if (need_exclusive_lock(img_req)) { + down_read(&rbd_dev->lock_rwsem); + mutex_lock(&img_req->state_mutex); + done = rbd_img_advance(img_req, result); + if (done) + rbd_lock_del_request(img_req); + mutex_unlock(&img_req->state_mutex); + up_read(&rbd_dev->lock_rwsem); + } else { + mutex_lock(&img_req->state_mutex); + done = rbd_img_advance(img_req, result); + mutex_unlock(&img_req->state_mutex); + } if (done && *result) { rbd_assert(*result < 0); @@ -3413,30 +3473,40 @@ again: static bool rbd_quiesce_lock(struct rbd_device *rbd_dev) { + bool need_wait; + dout("%s rbd_dev %p\n", __func__, rbd_dev); lockdep_assert_held_exclusive(&rbd_dev->lock_rwsem); if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED) return false; - rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING; - downgrade_write(&rbd_dev->lock_rwsem); /* * Ensure that all in-flight IO is flushed. - * - * FIXME: ceph_osdc_sync() flushes the entire OSD client, which - * may be shared with other devices. */ - ceph_osdc_sync(&rbd_dev->rbd_client->client->osdc); + rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING; + rbd_assert(!completion_done(&rbd_dev->releasing_wait)); + need_wait = !list_empty(&rbd_dev->running_list); + downgrade_write(&rbd_dev->lock_rwsem); + if (need_wait) + wait_for_completion(&rbd_dev->releasing_wait); up_read(&rbd_dev->lock_rwsem); down_write(&rbd_dev->lock_rwsem); if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING) return false; + rbd_assert(list_empty(&rbd_dev->running_list)); return true; } +static void __rbd_release_lock(struct rbd_device *rbd_dev) +{ + rbd_assert(list_empty(&rbd_dev->running_list)); + + rbd_unlock(rbd_dev); +} + /* * lock_rwsem must be held for write */ @@ -3445,7 +3515,7 @@ static void rbd_release_lock(struct rbd_device *rbd_dev) if (!rbd_quiesce_lock(rbd_dev)) return; - rbd_unlock(rbd_dev); + __rbd_release_lock(rbd_dev); /* * Give others a chance to grab the lock - we would re-acquire @@ -3819,7 +3889,7 @@ static void rbd_reacquire_lock(struct rbd_device *rbd_dev) * Lock cookie cannot be updated on older OSDs, so do * a manual release and queue an acquire. */ - rbd_unlock(rbd_dev); + __rbd_release_lock(rbd_dev); queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0); } else { __rbd_lock(rbd_dev, cookie); @@ -4085,9 +4155,12 @@ static void rbd_queue_workfn(struct work_struct *work) if (result) goto err_img_request; - rbd_img_handle_request(img_request, 0); - if (must_be_locked) + if (must_be_locked) { + rbd_lock_add_request(img_request); up_read(&rbd_dev->lock_rwsem); + } + + rbd_img_handle_request(img_request, 0); return; err_img_request: @@ -4761,6 +4834,9 @@ static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc, INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock); INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock); INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work); + spin_lock_init(&rbd_dev->lock_lists_lock); + INIT_LIST_HEAD(&rbd_dev->running_list); + init_completion(&rbd_dev->releasing_wait); init_waitqueue_head(&rbd_dev->lock_waitq); rbd_dev->dev.bus = &rbd_bus_type; @@ -5777,7 +5853,7 @@ static void rbd_dev_image_unlock(struct rbd_device *rbd_dev) { down_write(&rbd_dev->lock_rwsem); if (__rbd_is_lock_owner(rbd_dev)) - rbd_unlock(rbd_dev); + __rbd_release_lock(rbd_dev); up_write(&rbd_dev->lock_rwsem); } |