diff options
| author | Jason Gunthorpe <jgg@nvidia.com> | 2022-09-23 11:26:52 +0200 |
|---|---|---|
| committer | Alex Williamson <alex.williamson@redhat.com> | 2022-10-04 12:06:58 -0600 |
| commit | 9c799c224d6ebc5be51065bd3217a2d7eea23b8f (patch) | |
| tree | d09166f170afc9fc32ecfe8205964a6257b81990 /samples/vfio-mdev | |
| parent | 685a1537f4c603cfcaf4b9be56ff6a571f7ddd08 (diff) | |
vfio/mdev: add mdev available instance checking to the core
Many of the mdev drivers use a simple counter for keeping track of the
available instances. Move this code to the core code and store the counter
in the mdev_parent. Implement it using correct locking, fixing mdpy.
Drivers just provide the value in the mdev_driver at registration time
and the core code takes care of maintaining it and exposing the value in
sysfs.
[hch: count instances per-parent instead of per-type, use an atomic_t
to avoid taking mdev_list_lock in the show method]
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/20220923092652.100656-15-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'samples/vfio-mdev')
| -rw-r--r-- | samples/vfio-mdev/mdpy.c | 22 |
1 files changed, 4 insertions, 18 deletions
diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c index a7cf59246ddd..946e8cfde6fd 100644 --- a/samples/vfio-mdev/mdpy.c +++ b/samples/vfio-mdev/mdpy.c @@ -42,11 +42,6 @@ MODULE_LICENSE("GPL v2"); -static int max_devices = 4; -module_param_named(count, max_devices, int, 0444); -MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices"); - - #define MDPY_TYPE_1 "vga" #define MDPY_TYPE_2 "xga" #define MDPY_TYPE_3 "hd" @@ -93,7 +88,6 @@ static struct class *mdpy_class; static struct cdev mdpy_cdev; static struct device mdpy_dev; static struct mdev_parent mdpy_parent; -static u32 mdpy_count; static const struct vfio_device_ops mdpy_dev_ops; /* State of each mdev device */ @@ -235,9 +229,6 @@ static int mdpy_init_dev(struct vfio_device *vdev) u32 fbsize; int ret = -ENOMEM; - if (mdpy_count >= max_devices) - return ret; - mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL); if (!mdev_state->vconfig) return ret; @@ -257,8 +248,6 @@ static int mdpy_init_dev(struct vfio_device *vdev) dev_info(vdev->dev, "%s: %s (%dx%d)\n", __func__, type->type.pretty_name, type->width, type->height); - - mdpy_count++; return 0; out_vconfig: @@ -292,7 +281,6 @@ static void mdpy_release_dev(struct vfio_device *vdev) struct mdev_state *mdev_state = container_of(vdev, struct mdev_state, vdev); - mdpy_count--; vfree(mdev_state->memblk); kfree(mdev_state->vconfig); vfio_free_device(vdev); @@ -669,11 +657,6 @@ static ssize_t mdpy_show_description(struct mdev_type *mtype, char *buf) type->width, type->height); } -static unsigned int mdpy_get_available(struct mdev_type *mtype) -{ - return max_devices - mdpy_count; -} - static const struct vfio_device_ops mdpy_dev_ops = { .init = mdpy_init_dev, .release = mdpy_release_dev, @@ -685,6 +668,7 @@ static const struct vfio_device_ops mdpy_dev_ops = { static struct mdev_driver mdpy_driver = { .device_api = VFIO_DEVICE_API_PCI_STRING, + .max_instances = 4, .driver = { .name = "mdpy", .owner = THIS_MODULE, @@ -693,7 +677,6 @@ static struct mdev_driver mdpy_driver = { }, .probe = mdpy_probe, .remove = mdpy_remove, - .get_available = mdpy_get_available, .show_description = mdpy_show_description, }; @@ -770,5 +753,8 @@ static void __exit mdpy_dev_exit(void) mdpy_class = NULL; } +module_param_named(count, mdpy_driver.max_instances, int, 0444); +MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices"); + module_init(mdpy_dev_init) module_exit(mdpy_dev_exit) |