From 2fd585f4ed9de9b9259e95affdd7d8cde06b48c3 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 5 Aug 2021 22:19:00 -0300 Subject: vfio: Provide better generic support for open/release vfio_device_ops Currently the driver ops have an open/release pair that is called once each time a device FD is opened or closed. Add an additional set of open/close_device() ops which are called when the device FD is opened for the first time and closed for the last time. An analysis shows that all of the drivers require this semantic. Some are open coding it as part of their reflck implementation, and some are just buggy and miss it completely. To retain the current semantics PCI and FSL depend on, introduce the idea of a "device set" which is a grouping of vfio_device's that share the same lock around opening. The device set is established by providing a 'set_id' pointer. All vfio_device's that provide the same pointer will be joined to the same singleton memory and lock across the whole set. This effectively replaces the oddly named reflck. After conversion the set_id will be sourced from: - A struct device from a fsl_mc_device (fsl) - A struct pci_slot (pci) - A struct pci_bus (pci) - The struct vfio_device (everything) The design ensures that the above pointers are live as long as the vfio_device is registered, so they form reliable unique keys to group vfio_devices into sets. This implementation uses xarray instead of searching through the driver core structures, which simplifies the somewhat tricky locking in this area. Following patches convert all the drivers. Signed-off-by: Yishai Hadas Reviewed-by: Cornelia Huck Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/4-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- include/linux/mdev.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/mdev.h') diff --git a/include/linux/mdev.h b/include/linux/mdev.h index 3a38598c2605..cb5b7ed1d7c3 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -111,6 +111,8 @@ struct mdev_parent_ops { int (*create)(struct mdev_device *mdev); int (*remove)(struct mdev_device *mdev); + int (*open_device)(struct mdev_device *mdev); + void (*close_device)(struct mdev_device *mdev); int (*open)(struct mdev_device *mdev); void (*release)(struct mdev_device *mdev); ssize_t (*read)(struct mdev_device *mdev, char __user *buf, -- cgit v1.2.3 From eb24c1007e6852e024dc33b0dd9617b8500a1291 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Thu, 5 Aug 2021 22:19:10 -0300 Subject: vfio: Remove struct vfio_device_ops open/release Nothing uses this anymore, delete it. Signed-off-by: Yishai Hadas Reviewed-by: Christoph Hellwig Signed-off-by: Jason Gunthorpe Reviewed-by: Cornelia Huck Link: https://lore.kernel.org/r/14-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com Signed-off-by: Alex Williamson --- drivers/vfio/mdev/vfio_mdev.c | 22 ---------------------- drivers/vfio/vfio.c | 14 +------------- include/linux/mdev.h | 7 ------- include/linux/vfio.h | 4 ---- 4 files changed, 1 insertion(+), 46 deletions(-) (limited to 'include/linux/mdev.h') diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c index e12196ffd487..7a9883048216 100644 --- a/drivers/vfio/mdev/vfio_mdev.c +++ b/drivers/vfio/mdev/vfio_mdev.c @@ -37,26 +37,6 @@ static void vfio_mdev_close_device(struct vfio_device *core_vdev) parent->ops->close_device(mdev); } -static int vfio_mdev_open(struct vfio_device *core_vdev) -{ - struct mdev_device *mdev = to_mdev_device(core_vdev->dev); - struct mdev_parent *parent = mdev->type->parent; - - if (unlikely(!parent->ops->open)) - return 0; - - return parent->ops->open(mdev); -} - -static void vfio_mdev_release(struct vfio_device *core_vdev) -{ - struct mdev_device *mdev = to_mdev_device(core_vdev->dev); - struct mdev_parent *parent = mdev->type->parent; - - if (likely(parent->ops->release)) - parent->ops->release(mdev); -} - static long vfio_mdev_unlocked_ioctl(struct vfio_device *core_vdev, unsigned int cmd, unsigned long arg) { @@ -122,8 +102,6 @@ static const struct vfio_device_ops vfio_mdev_dev_ops = { .name = "vfio-mdev", .open_device = vfio_mdev_open_device, .close_device = vfio_mdev_close_device, - .open = vfio_mdev_open, - .release = vfio_mdev_release, .ioctl = vfio_mdev_unlocked_ioctl, .read = vfio_mdev_read, .write = vfio_mdev_write, diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 9cc17768c425..3c034fe14ccb 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1470,19 +1470,13 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf) } mutex_unlock(&device->dev_set->lock); - if (device->ops->open) { - ret = device->ops->open(device); - if (ret) - goto err_close_device; - } - /* * We can't use anon_inode_getfd() because we need to modify * the f_mode flags directly to allow more than just ioctls */ fdno = ret = get_unused_fd_flags(O_CLOEXEC); if (ret < 0) - goto err_release; + goto err_close_device; filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops, device, O_RDWR); @@ -1509,9 +1503,6 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf) err_fd: put_unused_fd(fdno); -err_release: - if (device->ops->release) - device->ops->release(device); err_close_device: mutex_lock(&device->dev_set->lock); if (device->open_count == 1 && device->ops->close_device) @@ -1659,9 +1650,6 @@ static int vfio_device_fops_release(struct inode *inode, struct file *filep) { struct vfio_device *device = filep->private_data; - if (device->ops->release) - device->ops->release(device); - mutex_lock(&device->dev_set->lock); if (!--device->open_count && device->ops->close_device) device->ops->close_device(device); diff --git a/include/linux/mdev.h b/include/linux/mdev.h index cb5b7ed1d7c3..68427e8fadeb 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -72,11 +72,6 @@ struct device *mtype_get_parent_dev(struct mdev_type *mtype); * @mdev: mdev_device device structure which is being * destroyed * Returns integer: success (0) or error (< 0) - * @open: Open mediated device. - * @mdev: mediated device. - * Returns integer: success (0) or error (< 0) - * @release: release mediated device - * @mdev: mediated device. * @read: Read emulation callback * @mdev: mediated device structure * @buf: read buffer @@ -113,8 +108,6 @@ struct mdev_parent_ops { int (*remove)(struct mdev_device *mdev); int (*open_device)(struct mdev_device *mdev); void (*close_device)(struct mdev_device *mdev); - int (*open)(struct mdev_device *mdev); - void (*release)(struct mdev_device *mdev); ssize_t (*read)(struct mdev_device *mdev, char __user *buf, size_t count, loff_t *ppos); ssize_t (*write)(struct mdev_device *mdev, const char __user *buf, diff --git a/include/linux/vfio.h b/include/linux/vfio.h index f0e6a72875e4..b53a9557884a 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -46,8 +46,6 @@ struct vfio_device { * * @open_device: Called when the first file descriptor is opened for this device * @close_device: Opposite of open_device - * @open: Called when userspace creates new file descriptor for device - * @release: Called when userspace releases file descriptor for device * @read: Perform read(2) on device file descriptor * @write: Perform write(2) on device file descriptor * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_* @@ -62,8 +60,6 @@ struct vfio_device_ops { char *name; int (*open_device)(struct vfio_device *vdev); void (*close_device)(struct vfio_device *vdev); - int (*open)(struct vfio_device *vdev); - void (*release)(struct vfio_device *vdev); ssize_t (*read)(struct vfio_device *vdev, char __user *buf, size_t count, loff_t *ppos); ssize_t (*write)(struct vfio_device *vdev, const char __user *buf, -- cgit v1.2.3