NVMe: Add a character device for each nvme device
Registers a miscellaneous device for each nvme controller probed. This
creates character device files as /dev/nvmeN, where N is the device
instance, and supports nvme admin ioctl commands so devices without
namespaces can be managed.
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-core.c b/drivers/block/nvme-core.c
index dbd2103..40908a0 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1647,6 +1647,56 @@
spin_unlock(&dev_list_lock);
}
+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);
+ iounmap(dev->bar);
+ nvme_release_instance(dev);
+ nvme_release_prp_pools(dev);
+ pci_disable_device(dev->pci_dev);
+ pci_release_regions(dev->pci_dev);
+ kfree(dev->queues);
+ kfree(dev->entry);
+ kfree(dev);
+}
+
+static int nvme_dev_open(struct inode *inode, struct file *f)
+{
+ struct nvme_dev *dev = container_of(f->private_data, struct nvme_dev,
+ miscdev);
+ kref_get(&dev->kref);
+ f->private_data = dev;
+ return 0;
+}
+
+static int nvme_dev_release(struct inode *inode, struct file *f)
+{
+ struct nvme_dev *dev = f->private_data;
+ kref_put(&dev->kref, nvme_free_dev);
+ return 0;
+}
+
+static long nvme_dev_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+{
+ struct nvme_dev *dev = f->private_data;
+ switch (cmd) {
+ case NVME_IOCTL_ADMIN_CMD:
+ return nvme_user_admin_cmd(dev, (void __user *)arg);
+ default:
+ return -ENOTTY;
+ }
+}
+
+static const struct file_operations nvme_dev_fops = {
+ .owner = THIS_MODULE,
+ .open = nvme_dev_open,
+ .release = nvme_dev_release,
+ .unlocked_ioctl = nvme_dev_ioctl,
+ .compat_ioctl = nvme_dev_ioctl,
+};
+
static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
int bars, result = -ENOMEM;
@@ -1705,8 +1755,20 @@
if (result)
goto delete;
+ scnprintf(dev->name, sizeof(dev->name), "nvme%d", dev->instance);
+ dev->miscdev.minor = MISC_DYNAMIC_MINOR;
+ dev->miscdev.parent = &pdev->dev;
+ dev->miscdev.name = dev->name;
+ dev->miscdev.fops = &nvme_dev_fops;
+ result = misc_register(&dev->miscdev);
+ if (result)
+ goto remove;
+
+ kref_init(&dev->kref);
return 0;
+ remove:
+ nvme_dev_remove(dev);
delete:
spin_lock(&dev_list_lock);
list_del(&dev->node);
@@ -1732,16 +1794,8 @@
static void nvme_remove(struct pci_dev *pdev)
{
struct nvme_dev *dev = pci_get_drvdata(pdev);
- nvme_dev_remove(dev);
- pci_disable_msix(pdev);
- iounmap(dev->bar);
- nvme_release_instance(dev);
- nvme_release_prp_pools(dev);
- pci_disable_device(pdev);
- pci_release_regions(pdev);
- kfree(dev->queues);
- kfree(dev->entry);
- kfree(dev);
+ misc_deregister(&dev->miscdev);
+ kref_put(&dev->kref, nvme_free_dev);
}
/* These functions are yet to be implemented */
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 7ae7ecf..9b6fba8 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -507,6 +507,8 @@
#ifdef __KERNEL__
#include <linux/pci.h>
+#include <linux/miscdevice.h>
+#include <linux/kref.h>
#define NVME_IO_TIMEOUT (5 * HZ)
@@ -527,6 +529,9 @@
struct msix_entry *entry;
struct nvme_bar __iomem *bar;
struct list_head namespaces;
+ struct kref kref;
+ struct miscdevice miscdev;
+ char name[12];
char serial[20];
char model[40];
char firmware_rev[8];