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 or 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.
Tested-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
Tested-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
Tested-by: Yanting Jiang <yanting.jiang@xxxxxxxxx>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx>
Tested-by: Terrence Xu <terrence.xu@xxxxxxxxx>
Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
drivers/vfio/device_cdev.c | 58 ++++++++++++++++++++++++++++++++++++++
drivers/vfio/vfio.h | 5 ++++
drivers/vfio/vfio_main.c | 15 +++++++++-
include/uapi/linux/vfio.h | 44 +++++++++++++++++++++++++++++
4 files changed, 121 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/device_cdev.c b/drivers/vfio/device_cdev.c
index f40784dd5561..e75da0a70d1f 100644
--- a/drivers/vfio/device_cdev.c
+++ b/drivers/vfio/device_cdev.c
@@ -152,6 +152,64 @@ void vfio_df_unbind_iommufd(struct vfio_device_file *df)
vfio_device_unblock_group(device);
}
+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;
+ struct vfio_device_attach_iommufd_pt attach;
+ unsigned long minsz;
+ int ret;
+
+ 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;
+
+ mutex_lock(&device->dev_set->lock);
+ ret = device->ops->attach_ioas(device, &attach.pt_id);
+ if (ret)
+ goto out_unlock;
+
+ if (copy_to_user(&arg->pt_id, &attach.pt_id, sizeof(attach.pt_id))) {
+ ret = -EFAULT;
+ 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_df_ioctl_detach_pt(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;
+
+ mutex_lock(&device->dev_set->lock);
+ 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 137d3e9ca798..1493bf8f4086 100644
--- a/drivers/vfio/vfio.h
+++ b/drivers/vfio/vfio.h
@@ -266,6 +266,11 @@ vfio_iommufd_compat_attach_ioas(struct vfio_device *device,
}
#endif
+int vfio_df_ioctl_attach_pt(struct vfio_device_file *df,
+ struct vfio_device_attach_iommufd_pt __user *arg);
+int vfio_df_ioctl_detach_pt(struct vfio_device_file *df,
+ struct vfio_device_detach_iommufd_pt __user *arg);
+
#if IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV)
void vfio_init_device_cdev(struct vfio_device *device);
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 9fdf93ff17cf..ba1d84afe081 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -1162,6 +1162,19 @@ static long vfio_device_fops_unl_ioctl(struct file *filep,
if (ret)
return ret;
+ /* cdev only ioctls */
+ if (IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV) && !df->group) {
+ switch (cmd) {
+ case VFIO_DEVICE_ATTACH_IOMMUFD_PT:
+ ret = vfio_df_ioctl_attach_pt(df, uptr);
+ goto out;
+
+ case VFIO_DEVICE_DETACH_IOMMUFD_PT:
+ ret = vfio_df_ioctl_detach_pt(df, uptr);
+ goto out;
+ }
+ }
+
switch (cmd) {
case VFIO_DEVICE_FEATURE:
ret = vfio_ioctl_device_feature(device, uptr);
@@ -1174,7 +1187,7 @@ static long vfio_device_fops_unl_ioctl(struct file *filep,
ret = device->ops->ioctl(device, cmd, arg);
break;
}
-
+out:
vfio_device_pm_runtime_put(device);
return ret;
}
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 098946b23e86..fa06e3eb4955 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -924,6 +924,50 @@ struct vfio_device_bind_iommufd {
#define VFIO_DEVICE_BIND_IOMMUFD _IO(VFIO_TYPE, VFIO_BASE + 18)
+/*
+ * 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.
+ * @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.
+ *
+ * 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.
+ *
+ * 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 + 19)
+
+/*
+ * 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.
+ *
+ * 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.
+ *
+ * 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 + 20)
+
/*
* Provide support for setting a PCI VF Token, which is used as a shared
* secret between PF and VF drivers. This feature may only be set on a
--
2.34.1
