From 5f3874c2a2310d9bd6969ca6764961d27a843b9d Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Tue, 24 Mar 2020 09:28:25 -0600 Subject: vfio: Include optional device match in vfio_device_ops callbacks Allow bus drivers to provide their own callback to match a device to the user provided string. Reviewed-by: Cornelia Huck Reviewed-by: Kevin Tian Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 20 ++++++++++++++++---- include/linux/vfio.h | 4 ++++ 2 files changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index c8482624ca34..0bd77d6ea691 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -875,11 +875,23 @@ EXPORT_SYMBOL_GPL(vfio_device_get_from_dev); static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group, char *buf) { - struct vfio_device *it, *device = NULL; + struct vfio_device *it, *device = ERR_PTR(-ENODEV); mutex_lock(&group->device_lock); list_for_each_entry(it, &group->device_list, group_next) { - if (!strcmp(dev_name(it->dev), buf)) { + int ret; + + if (it->ops->match) { + ret = it->ops->match(it->device_data, buf); + if (ret < 0) { + device = ERR_PTR(ret); + break; + } + } else { + ret = !strcmp(dev_name(it->dev), buf); + } + + if (ret) { device = it; vfio_device_get(device); break; @@ -1430,8 +1442,8 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf) return -EPERM; device = vfio_device_get_from_name(group, buf); - if (!device) - return -ENODEV; + if (IS_ERR(device)) + return PTR_ERR(device); ret = device->ops->open(device->device_data); if (ret) { diff --git a/include/linux/vfio.h b/include/linux/vfio.h index e42a711a2800..029694b977f2 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -26,6 +26,9 @@ * operations documented below * @mmap: Perform mmap(2) on a region of the device file descriptor * @request: Request for the bus driver to release the device + * @match: Optional device name match callback (return: 0 for no-match, >0 for + * match, -errno for abort (ex. match with insufficient or incorrect + * additional args) */ struct vfio_device_ops { char *name; @@ -39,6 +42,7 @@ struct vfio_device_ops { unsigned long arg); int (*mmap)(void *device_data, struct vm_area_struct *vma); void (*request)(void *device_data, unsigned int count); + int (*match)(void *device_data, char *buf); }; extern struct iommu_group *vfio_iommu_group_get(struct device *dev); -- cgit v1.2.3-59-g8ed1b