diff options
| author | Jens Axboe <axboe@fb.com> | 2015-11-03 20:37:26 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-11-07 10:40:47 -0700 |
| commit | a0fa9647a54e81883abd57c5c865d1747f68a577 (patch) | |
| tree | f017a7459fd6e0cc36b0e004c7d4a059b5a04c15 /drivers/nvme | |
| parent | 05229beeddf7e75e2e616ddaad4b70e7fca9528d (diff) | |
| download | lwn-a0fa9647a54e81883abd57c5c865d1747f68a577.tar.gz lwn-a0fa9647a54e81883abd57c5c865d1747f68a577.zip | |
NVMe: add blk polling support
Add nvme_poll(), which will check a specific completion queue for
command completions. Wire that up to the new block layer poll
mechanism.
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Diffstat (limited to 'drivers/nvme')
| -rw-r--r-- | drivers/nvme/host/pci.c | 32 |
1 files changed, 28 insertions, 4 deletions
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index e878590e71b6..4a715f49f5db 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -90,7 +90,7 @@ static struct class *nvme_class; static int __nvme_reset(struct nvme_dev *dev); static int nvme_reset(struct nvme_dev *dev); -static int nvme_process_cq(struct nvme_queue *nvmeq); +static void nvme_process_cq(struct nvme_queue *nvmeq); static void nvme_dead_ctrl(struct nvme_dev *dev); struct async_cmd_info { @@ -935,7 +935,7 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx, return BLK_MQ_RQ_QUEUE_BUSY; } -static int nvme_process_cq(struct nvme_queue *nvmeq) +static void __nvme_process_cq(struct nvme_queue *nvmeq, unsigned int *tag) { u16 head, phase; @@ -953,6 +953,8 @@ static int nvme_process_cq(struct nvme_queue *nvmeq) head = 0; phase = !phase; } + if (tag && *tag == cqe.command_id) + *tag = -1; ctx = nvme_finish_cmd(nvmeq, cqe.command_id, &fn); fn(nvmeq, ctx, &cqe); } @@ -964,14 +966,18 @@ static int nvme_process_cq(struct nvme_queue *nvmeq) * a big problem. */ if (head == nvmeq->cq_head && phase == nvmeq->cq_phase) - return 0; + return; writel(head, nvmeq->q_db + nvmeq->dev->db_stride); nvmeq->cq_head = head; nvmeq->cq_phase = phase; nvmeq->cqe_seen = 1; - return 1; +} + +static void nvme_process_cq(struct nvme_queue *nvmeq) +{ + __nvme_process_cq(nvmeq, NULL); } static irqreturn_t nvme_irq(int irq, void *data) @@ -995,6 +1001,23 @@ static irqreturn_t nvme_irq_check(int irq, void *data) return IRQ_WAKE_THREAD; } +static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag) +{ + struct nvme_queue *nvmeq = hctx->driver_data; + + if ((le16_to_cpu(nvmeq->cqes[nvmeq->cq_head].status) & 1) == + nvmeq->cq_phase) { + spin_lock_irq(&nvmeq->q_lock); + __nvme_process_cq(nvmeq, &tag); + spin_unlock_irq(&nvmeq->q_lock); + + if (tag == -1) + return 1; + } + + return 0; +} + /* * Returns 0 on success. If the result is negative, it's a Linux error code; * if the result is positive, it's an NVM Express status code @@ -1654,6 +1677,7 @@ static struct blk_mq_ops nvme_mq_ops = { .init_hctx = nvme_init_hctx, .init_request = nvme_init_request, .timeout = nvme_timeout, + .poll = nvme_poll, }; static void nvme_dev_remove_admin(struct nvme_dev *dev) |