On 2024/10/14 23:49, Alex Williamson wrote:
On Sat, 12 Oct 2024 21:49:05 +0800 Yi Liu yi.l.liu@intel.com wrote:
On 2024/10/1 20:11, Jason Gunthorpe wrote:
On Mon, Sep 30, 2024 at 07:55:08AM +0000, Tian, Kevin wrote:
+struct vfio_device_pasid_attach_iommufd_pt {
- __u32 argsz;
- __u32 flags;
- __u32 pasid;
- __u32 pt_id;
+};
+#define VFIO_DEVICE_PASID_ATTACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 21)
Not sure whether this was discussed before. Does it make sense to reuse the existing VFIO_DEVICE_ATTACH_IOMMUFD_PT by introducing a new pasid field and a new flag bit?
Maybe? I don't have a strong feeling either way.
There is somewhat less code if you reuse the ioctl at least
I had a rough memory that I was suggested to add a separate ioctl for PASID. Let's see Alex's opinion.
I don't recall any previous arguments for separate ioctls, but it seems to make a lot of sense to me to extend the existing ioctls with a flag to indicate pasid cscope and id. Thanks,
thanks for the confirmation. How about the below?
diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c index bb1817bd4ff3..c78533bce3c6 100644 --- a/drivers/vfio/device_cdev.c +++ b/drivers/vfio/device_cdev.c @@ -162,21 +162,34 @@ void vfio_df_unbind_iommufd(struct vfio_device_file *df) int vfio_df_ioctl_attach_pt(struct vfio_device_file *df, struct vfio_device_attach_iommufd_pt __user *arg) { - struct vfio_device *device = df->device; + unsigned long minsz = offsetofend( + struct vfio_device_attach_iommufd_pt, pt_id); struct vfio_device_attach_iommufd_pt attach; - unsigned long minsz; + struct vfio_device *device = df->device; + u32 user_size; int ret;
- minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); + ret = get_user(user_size, (u32 __user *)arg); + if (ret) + return ret;
- if (copy_from_user(&attach, arg, minsz)) - return -EFAULT; + ret = copy_struct_from_user(&attach, sizeof(attach), arg, user_size); + if (ret) + return ret;
- if (attach.argsz < minsz || attach.flags) + if (attach.argsz < minsz || attach.flags & (~VFIO_DEVICE_ATTACH_PASID)) return -EINVAL;
+ if ((attach.flags & VFIO_DEVICE_ATTACH_PASID) && + !device->ops->pasid_attach_ioas) + return -EOPNOTSUPP; + mutex_lock(&device->dev_set->lock); - ret = device->ops->attach_ioas(device, &attach.pt_id); + if (attach.flags & VFIO_DEVICE_ATTACH_PASID) + ret = device->ops->pasid_attach_ioas(device, attach.pasid, + &attach.pt_id); + else + ret = device->ops->attach_ioas(device, &attach.pt_id); if (ret) goto out_unlock;
@@ -198,20 +211,33 @@ int vfio_df_ioctl_attach_pt(struct vfio_device_file *df, int vfio_df_ioctl_detach_pt(struct vfio_device_file *df, struct vfio_device_detach_iommufd_pt __user *arg) { - struct vfio_device *device = df->device; + unsigned long minsz = + offsetofend(struct vfio_device_detach_iommufd_pt, flags); struct vfio_device_detach_iommufd_pt detach; - unsigned long minsz; + struct vfio_device *device = df->device; + u32 user_size; + int ret;
- minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); + ret = get_user(user_size, (u32 __user *)arg); + if (ret) + return ret;
- if (copy_from_user(&detach, arg, minsz)) - return -EFAULT; + ret = copy_struct_from_user(&detach, sizeof(detach), arg, user_size); + if (ret) + return ret;
- if (detach.argsz < minsz || detach.flags) + if (detach.argsz < minsz || detach.flags & (~VFIO_DEVICE_DETACH_PASID)) return -EINVAL;
+ if ((detach.flags & VFIO_DEVICE_DETACH_PASID) && + !device->ops->pasid_detach_ioas) + return -EOPNOTSUPP; + mutex_lock(&device->dev_set->lock); - device->ops->detach_ioas(device); + if (detach.flags & VFIO_DEVICE_DETACH_PASID) + device->ops->pasid_detach_ioas(device, detach.pasid); + else + device->ops->detach_ioas(device); mutex_unlock(&device->dev_set->lock);
return 0; diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 2b68e6cdf190..40b414e642f5 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -931,29 +931,34 @@ struct vfio_device_bind_iommufd { * VFIO_DEVICE_ATTACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 19, * struct vfio_device_attach_iommufd_pt) * @argsz: User filled size of this data. - * @flags: Must be 0. + * @flags: Flags for attach. * @pt_id: Input the target id which can represent an ioas or a hwpt * allocated via iommufd subsystem. * Output the input ioas id or the attached hwpt id which could * be the specified hwpt itself or a hwpt automatically created * for the specified ioas by kernel during the attachment. + * @pasid: The pasid to be attached, only meaningful when + * VFIO_DEVICE_ATTACH_PASID is set in @flags * * Associate the device with an address space within the bound iommufd. * Undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. This is only * allowed on cdev fds. * - * If a vfio device is currently attached to a valid hw_pagetable, without doing - * a VFIO_DEVICE_DETACH_IOMMUFD_PT, a second VFIO_DEVICE_ATTACH_IOMMUFD_PT ioctl - * passing in another hw_pagetable (hwpt) id is allowed. This action, also known - * as a hw_pagetable replacement, will replace the device's currently attached - * hw_pagetable with a new hw_pagetable corresponding to the given pt_id. + * If a vfio device or a pasid of this device is currently attached to a valid + * hw_pagetable (hwpt), without doing a VFIO_DEVICE_DETACH_IOMMUFD_PT, a second + * VFIO_DEVICE_ATTACH_IOMMUFD_PT ioctl passing in another hwpt id is allowed. + * This action, also known as a hw_pagetable replacement, will replace the + * currently attached hwpt of the device or the pasid of this device with a new + * hwpt corresponding to the given pt_id. * * Return: 0 on success, -errno on failure. */ struct vfio_device_attach_iommufd_pt { __u32 argsz; __u32 flags; +#define VFIO_DEVICE_ATTACH_PASID (1 << 0) __u32 pt_id; + __u32 pasid; };
#define VFIO_DEVICE_ATTACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 19) @@ -962,17 +967,21 @@ struct vfio_device_attach_iommufd_pt { * VFIO_DEVICE_DETACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 20, * struct vfio_device_detach_iommufd_pt) * @argsz: User filled size of this data. - * @flags: Must be 0. + * @flags: Flags for detach. + * @pasid: The pasid to be detached, only meaningful when + * VFIO_DEVICE_DETACH_PASID is set in @flags * - * Remove the association of the device and its current associated address - * space. After it, the device should be in a blocking DMA state. This is only - * allowed on cdev fds. + * Remove the association of the device or a pasid of the device and its current + * associated address space. After it, the device or the pasid should be in a + * blocking DMA state. This is only allowed on cdev fds. * * Return: 0 on success, -errno on failure. */ struct vfio_device_detach_iommufd_pt { __u32 argsz; __u32 flags; +#define VFIO_DEVICE_DETACH_PASID (1 << 0) + __u32 pasid; };
#define VFIO_DEVICE_DETACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 20)