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authorRamachandra Rao Gajula <rama@fastorsystems.com>2013-05-11 15:19:31 -0700
committerMatthew Wilcox <matthew.r.wilcox@intel.com>2013-05-31 11:45:52 -0400
commitfa08a396647767abd24a9e7015cb177121d0cf15 (patch)
tree3447b579447e68d3c1a1f888d0123610eb9db7d7 /drivers
parentcf9f123b38345b2c2777e642eb9bb561f4b7de91 (diff)
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NVMe: Add MSI support
Some devices only have support for MSI, not MSI-X. While MSI is more limited, it still provides better performance than line-based interrupts. Signed-off-by: Ramachandra Gajula <rama@fastorsystems.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/block/nvme-core.c40
1 files changed, 32 insertions, 8 deletions
diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index a57d3bcec803..ce79a590b45b 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1637,7 +1637,8 @@ static int set_queue_count(struct nvme_dev *dev, int count)
static int nvme_setup_io_queues(struct nvme_dev *dev)
{
- int result, cpu, i, nr_io_queues, db_bar_size, q_depth;
+ struct pci_dev *pdev = dev->pci_dev;
+ int result, cpu, i, nr_io_queues, db_bar_size, q_depth, q_count;
nr_io_queues = num_online_cpus();
result = set_queue_count(dev, nr_io_queues);
@@ -1646,14 +1647,14 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
if (result < nr_io_queues)
nr_io_queues = result;
+ q_count = nr_io_queues;
/* Deregister the admin queue's interrupt */
free_irq(dev->entry[0].vector, dev->queues[0]);
db_bar_size = 4096 + ((nr_io_queues + 1) << (dev->db_stride + 3));
if (db_bar_size > 8192) {
iounmap(dev->bar);
- dev->bar = ioremap(pci_resource_start(dev->pci_dev, 0),
- db_bar_size);
+ dev->bar = ioremap(pci_resource_start(pdev, 0), db_bar_size);
dev->dbs = ((void __iomem *)dev->bar) + 4096;
dev->queues[0]->q_db = dev->dbs;
}
@@ -1661,19 +1662,36 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
for (i = 0; i < nr_io_queues; i++)
dev->entry[i].entry = i;
for (;;) {
- result = pci_enable_msix(dev->pci_dev, dev->entry,
- nr_io_queues);
+ result = pci_enable_msix(pdev, dev->entry, nr_io_queues);
if (result == 0) {
break;
} else if (result > 0) {
nr_io_queues = result;
continue;
} else {
- nr_io_queues = 1;
+ nr_io_queues = 0;
break;
}
}
+ if (nr_io_queues == 0) {
+ nr_io_queues = q_count;
+ for (;;) {
+ result = pci_enable_msi_block(pdev, nr_io_queues);
+ if (result == 0) {
+ for (i = 0; i < nr_io_queues; i++)
+ dev->entry[i].vector = i + pdev->irq;
+ break;
+ } else if (result > 0) {
+ nr_io_queues = result;
+ continue;
+ } else {
+ nr_io_queues = 1;
+ break;
+ }
+ }
+ }
+
result = queue_request_irq(dev, dev->queues[0], "nvme admin");
/* XXX: handle failure here */
@@ -1854,7 +1872,10 @@ static void nvme_free_dev(struct kref *kref)
{
struct nvme_dev *dev = container_of(kref, struct nvme_dev, kref);
nvme_dev_remove(dev);
- pci_disable_msix(dev->pci_dev);
+ if (dev->pci_dev->msi_enabled)
+ pci_disable_msi(dev->pci_dev);
+ else if (dev->pci_dev->msix_enabled)
+ pci_disable_msix(dev->pci_dev);
iounmap(dev->bar);
nvme_release_instance(dev);
nvme_release_prp_pools(dev);
@@ -1987,7 +2008,10 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
unmap:
iounmap(dev->bar);
disable_msix:
- pci_disable_msix(pdev);
+ if (dev->pci_dev->msi_enabled)
+ pci_disable_msi(dev->pci_dev);
+ else if (dev->pci_dev->msix_enabled)
+ pci_disable_msix(dev->pci_dev);
nvme_release_instance(dev);
nvme_release_prp_pools(dev);
disable: