From 2f18d46683cb3047c41229d57cf7c6e2ee48676f Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Wed, 4 Apr 2018 10:15:38 +0200 Subject: [PATCH] rbd: refactor rbd_wait_state_locked() In preparation for lock_timeout option, make rbd_wait_state_locked() return error codes. Signed-off-by: Ilya Dryomov --- drivers/block/rbd.c | 43 ++++++++++++++++++++++++++----------------- 1 file changed, 26 insertions(+), 17 deletions(-) diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 07dc5419bd63..f4b1b91e6d4d 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -3533,9 +3533,21 @@ static int rbd_obj_method_sync(struct rbd_device *rbd_dev, /* * lock_rwsem must be held for read */ -static void rbd_wait_state_locked(struct rbd_device *rbd_dev) +static int rbd_wait_state_locked(struct rbd_device *rbd_dev, bool may_acquire) { DEFINE_WAIT(wait); + int ret = 0; + + if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) + return -EBLACKLISTED; + + if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) + return 0; + + if (!may_acquire) { + rbd_warn(rbd_dev, "exclusive lock required"); + return -EROFS; + } do { /* @@ -3549,10 +3561,14 @@ static void rbd_wait_state_locked(struct rbd_device *rbd_dev) up_read(&rbd_dev->lock_rwsem); schedule(); down_read(&rbd_dev->lock_rwsem); - } while (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED && - !test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)); + if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { + ret = -EBLACKLISTED; + break; + } + } while (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED); finish_wait(&rbd_dev->lock_waitq, &wait); + return ret; } static void rbd_queue_workfn(struct work_struct *work) @@ -3638,19 +3654,10 @@ static void rbd_queue_workfn(struct work_struct *work) (op_type != OBJ_OP_READ || rbd_dev->opts->lock_on_read); if (must_be_locked) { down_read(&rbd_dev->lock_rwsem); - if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED && - !test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { - if (rbd_dev->opts->exclusive) { - rbd_warn(rbd_dev, "exclusive lock required"); - result = -EROFS; - goto err_unlock; - } - rbd_wait_state_locked(rbd_dev); - } - if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { - result = -EBLACKLISTED; + result = rbd_wait_state_locked(rbd_dev, + !rbd_dev->opts->exclusive); + if (result) goto err_unlock; - } } img_request = rbd_img_request_create(rbd_dev, op_type, snapc); @@ -5216,6 +5223,8 @@ static void rbd_dev_image_unlock(struct rbd_device *rbd_dev) static int rbd_add_acquire_lock(struct rbd_device *rbd_dev) { + int ret; + if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) { rbd_warn(rbd_dev, "exclusive-lock feature is not enabled"); return -EINVAL; @@ -5223,9 +5232,9 @@ static int rbd_add_acquire_lock(struct rbd_device *rbd_dev) /* FIXME: "rbd map --exclusive" should be in interruptible */ down_read(&rbd_dev->lock_rwsem); - rbd_wait_state_locked(rbd_dev); + ret = rbd_wait_state_locked(rbd_dev, true); up_read(&rbd_dev->lock_rwsem); - if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { + if (ret) { rbd_warn(rbd_dev, "failed to acquire exclusive lock"); return -EROFS; } -- 2.30.2