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| author | Keith Busch <keith.busch@intel.com> | 2014-05-13 10:32:46 -0600 |
|---|---|---|
| committer | Matthew Wilcox <matthew.r.wilcox@intel.com> | 2014-06-03 22:58:34 -0400 |
| commit | a51afb54339c5e9ee72df66ae0f2ac5aacfed365 (patch) | |
| tree | fcaf5e2e3ccc53195f844954cff0713053803dd4 /drivers | |
| parent | de672b9748f78dcbc663e12ea44cb24dc287baf0 (diff) | |
| download | linux-a51afb54339c5e9ee72df66ae0f2ac5aacfed365.tar.gz linux-a51afb54339c5e9ee72df66ae0f2ac5aacfed365.tar.bz2 linux-a51afb54339c5e9ee72df66ae0f2ac5aacfed365.zip | |
NVMe: Fix nvme get/put queue semantics
The routines to get and lock nvme queues required the caller to "put"
or "unlock" them even if getting one returned NULL. This patch fixes that.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/block/nvme-core.c | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index 12c57eb7c915..29a3e85873b5 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -285,9 +285,17 @@ static struct nvme_queue *raw_nvmeq(struct nvme_dev *dev, int qid) static struct nvme_queue *get_nvmeq(struct nvme_dev *dev) __acquires(RCU) { + struct nvme_queue *nvmeq; unsigned queue_id = get_cpu_var(*dev->io_queue); + rcu_read_lock(); - return rcu_dereference(dev->queues[queue_id]); + nvmeq = rcu_dereference(dev->queues[queue_id]); + if (nvmeq) + return nvmeq; + + rcu_read_unlock(); + put_cpu_var(*dev->io_queue); + return NULL; } static void put_nvmeq(struct nvme_queue *nvmeq) __releases(RCU) @@ -299,8 +307,15 @@ static void put_nvmeq(struct nvme_queue *nvmeq) __releases(RCU) static struct nvme_queue *lock_nvmeq(struct nvme_dev *dev, int q_idx) __acquires(RCU) { + struct nvme_queue *nvmeq; + rcu_read_lock(); - return rcu_dereference(dev->queues[q_idx]); + nvmeq = rcu_dereference(dev->queues[q_idx]); + if (nvmeq) + return nvmeq; + + rcu_read_unlock(); + return NULL; } static void unlock_nvmeq(struct nvme_queue *nvmeq) __releases(RCU) @@ -809,7 +824,6 @@ static void nvme_make_request(struct request_queue *q, struct bio *bio) int result = -EBUSY; if (!nvmeq) { - put_nvmeq(NULL); bio_endio(bio, -EIO); return; } @@ -884,10 +898,8 @@ static int nvme_submit_sync_cmd(struct nvme_dev *dev, int q_idx, struct nvme_queue *nvmeq; nvmeq = lock_nvmeq(dev, q_idx); - if (!nvmeq) { - unlock_nvmeq(nvmeq); + if (!nvmeq) return -ENODEV; - } cmdinfo.task = current; cmdinfo.status = -EINTR; @@ -912,9 +924,10 @@ static int nvme_submit_sync_cmd(struct nvme_dev *dev, int q_idx, if (cmdinfo.status == -EINTR) { nvmeq = lock_nvmeq(dev, q_idx); - if (nvmeq) + if (nvmeq) { nvme_abort_command(nvmeq, cmdid); - unlock_nvmeq(nvmeq); + unlock_nvmeq(nvmeq); + } return -EINTR; } |