From 9a0be7abb62ff2a7dc3360ab45c31f29b3faf642 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 26 Nov 2015 11:09:06 +0100 Subject: [PATCH] nvme: refactor set_queue_count Split out a helper that just issues the Set Features and interprets the result which can go to common code, and document why we are ignoring non-timeout error returns in the PCIe driver. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/nvme/host/core.c | 16 ++++++++++++++++ drivers/nvme/host/nvme.h | 1 + drivers/nvme/host/pci.c | 34 +++++++++++++--------------------- 3 files changed, 30 insertions(+), 21 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 9c7dfd1476a7..c61bde9921d2 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -327,6 +327,22 @@ int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log) return error; } +int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count) +{ + u32 q_count = (*count - 1) | ((*count - 1) << 16); + u32 result; + int status, nr_io_queues; + + status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, 0, + &result); + if (status) + return status; + + nr_io_queues = min(result & 0xffff, result >> 16) + 1; + *count = min(*count, nr_io_queues); + return 0; +} + static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio) { struct nvme_user_io io; diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 93378be874e1..b75d41e5c378 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -232,6 +232,7 @@ int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid, dma_addr_t dma_addr, u32 *result); int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11, dma_addr_t dma_addr, u32 *result); +int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count); extern spinlock_t dev_list_lock; diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 87ad57bcc7ed..a64d0baacc58 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1559,23 +1559,6 @@ static void nvme_create_io_queues(struct nvme_dev *dev) } } -static int set_queue_count(struct nvme_dev *dev, int count) -{ - int status; - u32 result; - u32 q_count = (count - 1) | ((count - 1) << 16); - - status = nvme_set_features(&dev->ctrl, NVME_FEAT_NUM_QUEUES, q_count, 0, - &result); - if (status < 0) - return status; - if (status > 0) { - dev_err(dev->dev, "Could not set queue count (%d)\n", status); - return 0; - } - return min(result & 0xffff, result >> 16) + 1; -} - static void __iomem *nvme_map_cmb(struct nvme_dev *dev) { u64 szu, size, offset; @@ -1640,11 +1623,20 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) int result, i, vecs, nr_io_queues, size; nr_io_queues = num_possible_cpus(); - result = set_queue_count(dev, nr_io_queues); - if (result <= 0) + result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues); + if (result < 0) return result; - if (result < nr_io_queues) - nr_io_queues = result; + + /* + * Degraded controllers might return an error when setting the queue + * count. We still want to be able to bring them online and offer + * access to the admin queue, as that might be only way to fix them up. + */ + if (result > 0) { + dev_err(dev->dev, "Could not set queue count (%d)\n", result); + nr_io_queues = 0; + result = 0; + } if (dev->cmb && NVME_CMB_SQS(dev->cmbsz)) { result = nvme_cmb_qdepth(dev, nr_io_queues,