From b1a3b5c61d27299799a61e50e08f507b2e9a8a75 Mon Sep 17 00:00:00 2001 From: Yi Liu Date: Tue, 18 Jul 2023 06:55:26 -0700 Subject: [PATCH] vfio: Allocate per device file structure This is preparation for adding vfio device cdev support. vfio device cdev requires: 1) A per device file memory to store the kvm pointer set by KVM. It will be propagated to vfio_device:kvm after the device cdev file is bound to an iommufd. 2) A mechanism to block device access through device cdev fd before it is bound to an iommufd. To address the above requirements, this adds a per device file structure named vfio_device_file. For now, it's only a wrapper of struct vfio_device pointer. Other fields will be added to this per file structure in future commits. Reviewed-by: Kevin Tian Reviewed-by: Eric Auger Reviewed-by: Jason Gunthorpe Tested-by: Terrence Xu Tested-by: Nicolin Chen Tested-by: Matthew Rosato Tested-by: Yanting Jiang Tested-by: Shameer Kolothum Tested-by: Zhenzhong Duan Signed-off-by: Yi Liu Link: https://lore.kernel.org/r/20230718135551.6592-2-yi.l.liu@intel.com Signed-off-by: Alex Williamson --- drivers/vfio/group.c | 13 +++++++++++-- drivers/vfio/vfio.h | 6 ++++++ drivers/vfio/vfio_main.c | 31 ++++++++++++++++++++++++++----- 3 files changed, 43 insertions(+), 7 deletions(-) diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index fc75c10..fbba9fc 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -218,19 +218,26 @@ void vfio_device_group_close(struct vfio_device *device) static struct file *vfio_device_open_file(struct vfio_device *device) { + struct vfio_device_file *df; struct file *filep; int ret; + df = vfio_allocate_device_file(device); + if (IS_ERR(df)) { + ret = PTR_ERR(df); + goto err_out; + } + ret = vfio_device_group_open(device); if (ret) - goto err_out; + goto err_free; /* * We can't use anon_inode_getfd() because we need to modify * the f_mode flags directly to allow more than just ioctls */ filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops, - device, O_RDWR); + df, O_RDWR); if (IS_ERR(filep)) { ret = PTR_ERR(filep); goto err_close_device; @@ -254,6 +261,8 @@ static struct file *vfio_device_open_file(struct vfio_device *device) err_close_device: vfio_device_group_close(device); +err_free: + kfree(df); err_out: return ERR_PTR(ret); } diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index 7b19c62..87d3dd6 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -16,11 +16,17 @@ struct iommufd_ctx; struct iommu_group; struct vfio_container; +struct vfio_device_file { + struct vfio_device *device; +}; + void vfio_device_put_registration(struct vfio_device *device); bool vfio_device_try_get_registration(struct vfio_device *device); int vfio_device_open(struct vfio_device *device, struct iommufd_ctx *iommufd); void vfio_device_close(struct vfio_device *device, struct iommufd_ctx *iommufd); +struct vfio_device_file * +vfio_allocate_device_file(struct vfio_device *device); extern const struct file_operations vfio_device_fops; diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index ab4f3a7..39c1158 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -419,6 +419,20 @@ static bool vfio_assert_device_open(struct vfio_device *device) return !WARN_ON_ONCE(!READ_ONCE(device->open_count)); } +struct vfio_device_file * +vfio_allocate_device_file(struct vfio_device *device) +{ + struct vfio_device_file *df; + + df = kzalloc(sizeof(*df), GFP_KERNEL_ACCOUNT); + if (!df) + return ERR_PTR(-ENOMEM); + + df->device = device; + + return df; +} + static int vfio_device_first_open(struct vfio_device *device, struct iommufd_ctx *iommufd) { @@ -532,12 +546,15 @@ static inline void vfio_device_pm_runtime_put(struct vfio_device *device) */ static int vfio_device_fops_release(struct inode *inode, struct file *filep) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; vfio_device_group_close(device); vfio_device_put_registration(device); + kfree(df); + return 0; } @@ -1102,7 +1119,8 @@ static int vfio_ioctl_device_feature(struct vfio_device *device, static long vfio_device_fops_unl_ioctl(struct file *filep, unsigned int cmd, unsigned long arg) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; int ret; ret = vfio_device_pm_runtime_get(device); @@ -1129,7 +1147,8 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf, size_t count, loff_t *ppos) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; if (unlikely(!device->ops->read)) return -EINVAL; @@ -1141,7 +1160,8 @@ static ssize_t vfio_device_fops_write(struct file *filep, const char __user *buf, size_t count, loff_t *ppos) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; if (unlikely(!device->ops->write)) return -EINVAL; @@ -1151,7 +1171,8 @@ static ssize_t vfio_device_fops_write(struct file *filep, static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma) { - struct vfio_device *device = filep->private_data; + struct vfio_device_file *df = filep->private_data; + struct vfio_device *device = df->device; if (unlikely(!device->ops->mmap)) return -EINVAL; -- 2.7.4