NVMe: Do not set IO queue depth beyond device max
Set the depth for IO queues to the device's maximum supported queue
entries if the requested depth exceeds the device's capabilities.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c
index 11951fa..af1ef39 100644
--- a/drivers/block/nvme.c
+++ b/drivers/block/nvme.c
@@ -893,7 +893,8 @@
int depth, int vector)
{
struct device *dmadev = &dev->pci_dev->dev;
- unsigned extra = (depth / 8) + (depth * sizeof(struct nvme_cmd_info));
+ unsigned extra = DIV_ROUND_UP(depth, 8) + (depth *
+ sizeof(struct nvme_cmd_info));
struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq) + extra, GFP_KERNEL);
if (!nvmeq)
return NULL;
@@ -1391,7 +1392,7 @@
static int __devinit nvme_setup_io_queues(struct nvme_dev *dev)
{
- int result, cpu, i, nr_io_queues, db_bar_size;
+ int result, cpu, i, nr_io_queues, db_bar_size, q_depth;
nr_io_queues = num_online_cpus();
result = set_queue_count(dev, nr_io_queues);
@@ -1437,9 +1438,10 @@
cpu = cpumask_next(cpu, cpu_online_mask);
}
+ q_depth = min_t(int, NVME_CAP_MQES(readq(&dev->bar->cap)) + 1,
+ NVME_Q_DEPTH);
for (i = 0; i < nr_io_queues; i++) {
- dev->queues[i + 1] = nvme_create_queue(dev, i + 1,
- NVME_Q_DEPTH, i);
+ dev->queues[i + 1] = nvme_create_queue(dev, i + 1, q_depth, i);
if (IS_ERR(dev->queues[i + 1]))
return PTR_ERR(dev->queues[i + 1]);
dev->queue_count++;
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 8c71d20..c25ccca 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -35,6 +35,7 @@
__u64 acq; /* Admin CQ Base Address */
};
+#define NVME_CAP_MQES(cap) ((cap) & 0xffff)
#define NVME_CAP_TIMEOUT(cap) (((cap) >> 24) & 0xff)
#define NVME_CAP_STRIDE(cap) (((cap) >> 32) & 0xf)
#define NVME_CAP_MPSMIN(cap) (((cap) >> 48) & 0xf)