| Message ID | 20230327094047.47215-23-yi.l.liu@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add vfio_device cdev for iommufd support | expand |
Nit, ATDETACH? [AT|DE]TACH? On Mon, 27 Mar 2023 02:40:45 -0700 Yi Liu <yi.l.liu@intel.com> wrote: > This adds ioctl for userspace to attach device cdev fd to and detach > from IOAS/hw_pagetable managed by iommufd. > > VFIO_DEVICE_ATTACH_IOMMUFD_PT: attach vfio device to IOAS, hw_pagetable > managed by iommufd. Attach can be > undo by VFIO_DEVICE_DETACH_IOMMUFD_PT > or device fd close. > VFIO_DEVICE_DETACH_IOMMUFD_PT: detach vfio device from the current attached > IOAS or hw_pagetable managed by iommufd. > > Reviewed-by: Kevin Tian <kevin.tian@intel.com> > Tested-by: Terrence Xu <terrence.xu@intel.com> > Tested-by: Nicolin Chen <nicolinc@nvidia.com> > Tested-by: Matthew Rosato <mjrosato@linux.ibm.com> > Signed-off-by: Yi Liu <yi.l.liu@intel.com> > --- > drivers/vfio/device_cdev.c | 85 ++++++++++++++++++++++++++++++++++++++ > drivers/vfio/vfio.h | 16 +++++++ > drivers/vfio/vfio_main.c | 8 ++++ > include/uapi/linux/vfio.h | 52 +++++++++++++++++++++++ > 4 files changed, 161 insertions(+) > > diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c > index 2b563bac50b9..b5de997bff6d 100644 > --- a/drivers/vfio/device_cdev.c > +++ b/drivers/vfio/device_cdev.c > @@ -197,6 +197,91 @@ long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, > return ret; > } > > +int vfio_ioctl_device_attach(struct vfio_device_file *df, > + struct vfio_device_attach_iommufd_pt __user *arg) > +{ > + struct vfio_device *device = df->device; > + struct vfio_device_attach_iommufd_pt attach; > + unsigned long minsz; > + int ret; > + > + static_assert(__same_type(arg->pt_id, attach.pt_id)); Same comment as previous, given these are the same field of the same structure, I don't understand how this could ever assert. > + > + minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); > + > + if (copy_from_user(&attach, arg, minsz)) > + return -EFAULT; > + > + if (attach.argsz < minsz || attach.flags) > + return -EINVAL; > + > + if (!device->ops->bind_iommufd) > + return -ENODEV; Same as previous, we already require this to enable cdev support, so this seems ultra paranoid. > + > + /* ATTACH only allowed for cdev fds */ > + if (df->group) > + return -EINVAL; > + > + mutex_lock(&device->dev_set->lock); > + /* noiommufd mode doesn't allow attach */ > + if (!df->iommufd) { > + ret = -EOPNOTSUPP; > + goto out_unlock; > + } > + > + ret = device->ops->attach_ioas(device, &attach.pt_id); > + if (ret) > + goto out_unlock; > + > + ret = copy_to_user(&arg->pt_id, &attach.pt_id, > + sizeof(attach.pt_id)) ? -EFAULT : 0; > + if (ret) > + goto out_detach; > + mutex_unlock(&device->dev_set->lock); > + > + return 0; > + > +out_detach: > + device->ops->detach_ioas(device); > +out_unlock: > + mutex_unlock(&device->dev_set->lock); > + return ret; > +} > + > +int vfio_ioctl_device_detach(struct vfio_device_file *df, > + struct vfio_device_detach_iommufd_pt __user *arg) > +{ > + struct vfio_device *device = df->device; > + struct vfio_device_detach_iommufd_pt detach; > + unsigned long minsz; > + > + minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); > + > + if (copy_from_user(&detach, arg, minsz)) > + return -EFAULT; > + > + if (detach.argsz < minsz || detach.flags) > + return -EINVAL; > + > + if (!device->ops->bind_iommufd) > + return -ENODEV; > + > + /* DETACH only allowed for cdev fds */ > + if (df->group) > + return -EINVAL; > + > + mutex_lock(&device->dev_set->lock); > + /* noiommufd mode doesn't support detach */ > + if (!df->iommufd) { > + mutex_unlock(&device->dev_set->lock); > + return -EOPNOTSUPP; > + } > + device->ops->detach_ioas(device); > + mutex_unlock(&device->dev_set->lock); > + > + return 0; > +} For both of these, can't a user trigger the WARN_ON(!vdev->iommufd_device) if they call either of these before VFIO_DEVICE_BIND_IOMMUFD? Thanks, Alex > + > static char *vfio_device_devnode(const struct device *dev, umode_t *mode) > { > return kasprintf(GFP_KERNEL, "vfio/devices/%s", dev_name(dev)); > diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h > index ace3d52b0928..c199e410db18 100644 > --- a/drivers/vfio/vfio.h > +++ b/drivers/vfio/vfio.h > @@ -284,6 +284,10 @@ int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep); > void vfio_device_cdev_close(struct vfio_device_file *df); > long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, > struct vfio_device_bind_iommufd __user *arg); > +int vfio_ioctl_device_attach(struct vfio_device_file *df, > + struct vfio_device_attach_iommufd_pt __user *arg); > +int vfio_ioctl_device_detach(struct vfio_device_file *df, > + struct vfio_device_detach_iommufd_pt __user *arg); > int vfio_cdev_init(struct class *device_class); > void vfio_cdev_cleanup(void); > #else > @@ -317,6 +321,18 @@ static inline long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, > return -EOPNOTSUPP; > } > > +static inline int vfio_ioctl_device_attach(struct vfio_device_file *df, > + struct vfio_device_attach_iommufd_pt __user *arg) > +{ > + return -EOPNOTSUPP; > +} > + > +static inline int vfio_ioctl_device_detach(struct vfio_device_file *df, > + struct vfio_device_detach_iommufd_pt __user *arg) > +{ > + return -EOPNOTSUPP; > +} > + > static inline int vfio_cdev_init(struct class *device_class) > { > return 0; > diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c > index 375086c8803f..896d8bb49585 100644 > --- a/drivers/vfio/vfio_main.c > +++ b/drivers/vfio/vfio_main.c > @@ -1150,6 +1150,14 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, > ret = vfio_ioctl_device_feature(device, (void __user *)arg); > break; > > + case VFIO_DEVICE_ATTACH_IOMMUFD_PT: > + ret = vfio_ioctl_device_attach(df, (void __user *)arg); > + break; > + > + case VFIO_DEVICE_DETACH_IOMMUFD_PT: > + ret = vfio_ioctl_device_detach(df, (void __user *)arg); > + break; > + > default: > if (unlikely(!device->ops->ioctl)) > ret = -EINVAL; > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > index 62b2f2497525..bf6c97e759c7 100644 > --- a/include/uapi/linux/vfio.h > +++ b/include/uapi/linux/vfio.h > @@ -231,6 +231,58 @@ struct vfio_device_bind_iommufd { > > #define VFIO_DEVICE_BIND_IOMMUFD _IO(VFIO_TYPE, VFIO_BASE + 19) > > +/* > + * VFIO_DEVICE_ATTACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 20, > + * struct vfio_device_attach_iommufd_pt) > + * > + * Attach a vfio device to an iommufd address space specified by IOAS > + * id or hw_pagetable (hwpt) id. > + * > + * Available only after a device has been bound to iommufd via > + * VFIO_DEVICE_BIND_IOMMUFD > + * > + * Undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. > + * > + * @argsz: user filled size of this data. > + * @flags: must be 0. > + * @pt_id: Input the target id which can represent an ioas or a hwpt > + * allocated via iommufd subsystem. > + * Output 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. > + * > + * Return: 0 on success, -errno on failure. > + */ > +struct vfio_device_attach_iommufd_pt { > + __u32 argsz; > + __u32 flags; > + __u32 pt_id; > +}; > + > +#define VFIO_DEVICE_ATTACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 20) > + > +/* > + * VFIO_DEVICE_DETACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 21, > + * struct vfio_device_detach_iommufd_pt) > + * > + * Detach a vfio device from the iommufd address space it has been > + * attached to. After it, device should be in a blocking DMA state. > + * > + * Available only after a device has been bound to iommufd via > + * VFIO_DEVICE_BIND_IOMMUFD. > + * > + * @argsz: user filled size of this data. > + * @flags: must be 0. > + * > + * Return: 0 on success, -errno on failure. > + */ > +struct vfio_device_detach_iommufd_pt { > + __u32 argsz; > + __u32 flags; > +}; > + > +#define VFIO_DEVICE_DETACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 21) > + > /** > * VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 7, > * struct vfio_device_info)
> From: Alex Williamson <alex.williamson@redhat.com> > Sent: Thursday, March 30, 2023 5:19 AM > > > Nit, ATDETACH? [AT|DE]TACH? [AT|DE]TACH
diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c index 2b563bac50b9..b5de997bff6d 100644 --- a/drivers/vfio/device_cdev.c +++ b/drivers/vfio/device_cdev.c @@ -197,6 +197,91 @@ long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, return ret; } +int vfio_ioctl_device_attach(struct vfio_device_file *df, + struct vfio_device_attach_iommufd_pt __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_attach_iommufd_pt attach; + unsigned long minsz; + int ret; + + static_assert(__same_type(arg->pt_id, attach.pt_id)); + + minsz = offsetofend(struct vfio_device_attach_iommufd_pt, pt_id); + + if (copy_from_user(&attach, arg, minsz)) + return -EFAULT; + + if (attach.argsz < minsz || attach.flags) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + /* ATTACH only allowed for cdev fds */ + if (df->group) + return -EINVAL; + + mutex_lock(&device->dev_set->lock); + /* noiommufd mode doesn't allow attach */ + if (!df->iommufd) { + ret = -EOPNOTSUPP; + goto out_unlock; + } + + ret = device->ops->attach_ioas(device, &attach.pt_id); + if (ret) + goto out_unlock; + + ret = copy_to_user(&arg->pt_id, &attach.pt_id, + sizeof(attach.pt_id)) ? -EFAULT : 0; + if (ret) + goto out_detach; + mutex_unlock(&device->dev_set->lock); + + return 0; + +out_detach: + device->ops->detach_ioas(device); +out_unlock: + mutex_unlock(&device->dev_set->lock); + return ret; +} + +int vfio_ioctl_device_detach(struct vfio_device_file *df, + struct vfio_device_detach_iommufd_pt __user *arg) +{ + struct vfio_device *device = df->device; + struct vfio_device_detach_iommufd_pt detach; + unsigned long minsz; + + minsz = offsetofend(struct vfio_device_detach_iommufd_pt, flags); + + if (copy_from_user(&detach, arg, minsz)) + return -EFAULT; + + if (detach.argsz < minsz || detach.flags) + return -EINVAL; + + if (!device->ops->bind_iommufd) + return -ENODEV; + + /* DETACH only allowed for cdev fds */ + if (df->group) + return -EINVAL; + + mutex_lock(&device->dev_set->lock); + /* noiommufd mode doesn't support detach */ + if (!df->iommufd) { + mutex_unlock(&device->dev_set->lock); + return -EOPNOTSUPP; + } + device->ops->detach_ioas(device); + mutex_unlock(&device->dev_set->lock); + + return 0; +} + static char *vfio_device_devnode(const struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "vfio/devices/%s", dev_name(dev)); diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index ace3d52b0928..c199e410db18 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -284,6 +284,10 @@ int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep); void vfio_device_cdev_close(struct vfio_device_file *df); long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, struct vfio_device_bind_iommufd __user *arg); +int vfio_ioctl_device_attach(struct vfio_device_file *df, + struct vfio_device_attach_iommufd_pt __user *arg); +int vfio_ioctl_device_detach(struct vfio_device_file *df, + struct vfio_device_detach_iommufd_pt __user *arg); int vfio_cdev_init(struct class *device_class); void vfio_cdev_cleanup(void); #else @@ -317,6 +321,18 @@ static inline long vfio_device_ioctl_bind_iommufd(struct vfio_device_file *df, return -EOPNOTSUPP; } +static inline int vfio_ioctl_device_attach(struct vfio_device_file *df, + struct vfio_device_attach_iommufd_pt __user *arg) +{ + return -EOPNOTSUPP; +} + +static inline int vfio_ioctl_device_detach(struct vfio_device_file *df, + struct vfio_device_detach_iommufd_pt __user *arg) +{ + return -EOPNOTSUPP; +} + static inline int vfio_cdev_init(struct class *device_class) { return 0; diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 375086c8803f..896d8bb49585 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -1150,6 +1150,14 @@ static long vfio_device_fops_unl_ioctl(struct file *filep, ret = vfio_ioctl_device_feature(device, (void __user *)arg); break; + case VFIO_DEVICE_ATTACH_IOMMUFD_PT: + ret = vfio_ioctl_device_attach(df, (void __user *)arg); + break; + + case VFIO_DEVICE_DETACH_IOMMUFD_PT: + ret = vfio_ioctl_device_detach(df, (void __user *)arg); + break; + default: if (unlikely(!device->ops->ioctl)) ret = -EINVAL; diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 62b2f2497525..bf6c97e759c7 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -231,6 +231,58 @@ struct vfio_device_bind_iommufd { #define VFIO_DEVICE_BIND_IOMMUFD _IO(VFIO_TYPE, VFIO_BASE + 19) +/* + * VFIO_DEVICE_ATTACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 20, + * struct vfio_device_attach_iommufd_pt) + * + * Attach a vfio device to an iommufd address space specified by IOAS + * id or hw_pagetable (hwpt) id. + * + * Available only after a device has been bound to iommufd via + * VFIO_DEVICE_BIND_IOMMUFD + * + * Undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * @pt_id: Input the target id which can represent an ioas or a hwpt + * allocated via iommufd subsystem. + * Output 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. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_attach_iommufd_pt { + __u32 argsz; + __u32 flags; + __u32 pt_id; +}; + +#define VFIO_DEVICE_ATTACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 20) + +/* + * VFIO_DEVICE_DETACH_IOMMUFD_PT - _IOW(VFIO_TYPE, VFIO_BASE + 21, + * struct vfio_device_detach_iommufd_pt) + * + * Detach a vfio device from the iommufd address space it has been + * attached to. After it, device should be in a blocking DMA state. + * + * Available only after a device has been bound to iommufd via + * VFIO_DEVICE_BIND_IOMMUFD. + * + * @argsz: user filled size of this data. + * @flags: must be 0. + * + * Return: 0 on success, -errno on failure. + */ +struct vfio_device_detach_iommufd_pt { + __u32 argsz; + __u32 flags; +}; + +#define VFIO_DEVICE_DETACH_IOMMUFD_PT _IO(VFIO_TYPE, VFIO_BASE + 21) + /** * VFIO_DEVICE_GET_INFO - _IOR(VFIO_TYPE, VFIO_BASE + 7, * struct vfio_device_info)
This adds ioctl for userspace to attach device cdev fd to and detach from IOAS/hw_pagetable managed by iommufd. VFIO_DEVICE_ATTACH_IOMMUFD_PT: attach vfio device to IOAS, hw_pagetable managed by iommufd. Attach can be undo by VFIO_DEVICE_DETACH_IOMMUFD_PT or device fd close. VFIO_DEVICE_DETACH_IOMMUFD_PT: detach vfio device from the current attached IOAS or hw_pagetable managed by iommufd. Reviewed-by: Kevin Tian <kevin.tian@intel.com> Tested-by: Terrence Xu <terrence.xu@intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Tested-by: Matthew Rosato <mjrosato@linux.ibm.com> Signed-off-by: Yi Liu <yi.l.liu@intel.com> --- drivers/vfio/device_cdev.c | 85 ++++++++++++++++++++++++++++++++++++++ drivers/vfio/vfio.h | 16 +++++++ drivers/vfio/vfio_main.c | 8 ++++ include/uapi/linux/vfio.h | 52 +++++++++++++++++++++++ 4 files changed, 161 insertions(+)