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 /include | |
| 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 'include')
| -rw-r--r-- | include/linux/mdev.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/mdev.h b/include/linux/mdev.h index 33674cb5ed5d..139d05b26f82 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -45,6 +45,7 @@ struct mdev_parent { struct rw_semaphore unreg_sem; struct mdev_type **types; unsigned int nr_types; + atomic_t available_instances; }; static inline struct mdev_device *to_mdev_device(struct device *dev) @@ -55,6 +56,7 @@ static inline struct mdev_device *to_mdev_device(struct device *dev) /** * struct mdev_driver - Mediated device driver * @device_api: string to return for the device_api sysfs + * @max_instances: maximum number of instances supported (optional) * @probe: called when new device created * @remove: called when device removed * @get_available: Return the max number of instances that can be created @@ -63,6 +65,7 @@ static inline struct mdev_device *to_mdev_device(struct device *dev) **/ struct mdev_driver { const char *device_api; + unsigned int max_instances; int (*probe)(struct mdev_device *dev); void (*remove)(struct mdev_device *dev); unsigned int (*get_available)(struct mdev_type *mtype); |