[Qemu-devel] [PATCH v4 09/16] vfio: ccw: realize VFIO_DEVICE_GET_REGION_INFO ioctl

[Dong Jia Shi]

Introduce device information about vfio-ccw: VFIO_DEVICE_FLAGS_CCW.
Realize VFIO_DEVICE_GET_REGION_INFO ioctl for vfio-ccw.

Reviewed-by: Pierre Morel <address@hidden>
Signed-off-by: Dong Jia Shi <address@hidden>
---
 drivers/s390/cio/vfio_ccw_ops.c | 78 +++++++++++++++++++++++++++++++++++++++++
 include/uapi/linux/vfio.h       | 11 ++++++
 2 files changed, 89 insertions(+)

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 878c882..f3300dd 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -188,6 +188,83 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device 
*mdev,
        return count;
 }
 
+static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info)
+{
+       info->flags = VFIO_DEVICE_FLAGS_CCW;
+       info->num_regions = VFIO_CCW_NUM_REGIONS;
+       info->num_irqs = 0;
+
+       return 0;
+}
+
+static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info,
+                                        u16 *cap_type_id,
+                                        void **cap_type)
+{
+       switch (info->index) {
+       case VFIO_CCW_CONFIG_REGION_INDEX:
+               info->offset = 0;
+               info->size = sizeof(struct ccw_io_region);
+               info->flags = VFIO_REGION_INFO_FLAG_READ
+                             | VFIO_REGION_INFO_FLAG_WRITE;
+               return 0;
+       default:
+               return -EINVAL;
+       }
+}
+
+static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
+                                  unsigned int cmd,
+                                  unsigned long arg)
+{
+       int ret = 0;
+       unsigned long minsz;
+
+       switch (cmd) {
+       case VFIO_DEVICE_GET_INFO:
+       {
+               struct vfio_device_info info;
+
+               minsz = offsetofend(struct vfio_device_info, num_irqs);
+
+               if (copy_from_user(&info, (void __user *)arg, minsz))
+                       return -EFAULT;
+
+               if (info.argsz < minsz)
+                       return -EINVAL;
+
+               ret = vfio_ccw_mdev_get_device_info(&info);
+               if (ret)
+                       return ret;
+
+               return copy_to_user((void __user *)arg, &info, minsz);
+       }
+       case VFIO_DEVICE_GET_REGION_INFO:
+       {
+               struct vfio_region_info info;
+               u16 cap_type_id = 0;
+               void *cap_type = NULL;
+
+               minsz = offsetofend(struct vfio_region_info, offset);
+
+               if (copy_from_user(&info, (void __user *)arg, minsz))
+                       return -EFAULT;
+
+               if (info.argsz < minsz)
+                       return -EINVAL;
+
+               ret = vfio_ccw_mdev_get_region_info(&info, &cap_type_id,
+                                                   &cap_type);
+               if (ret)
+                       return ret;
+
+               return copy_to_user((void __user *)arg, &info, minsz);
+       }
+       default:
+               return -ENOTTY;
+       }
+}
+
 static const struct mdev_parent_ops vfio_ccw_mdev_ops = {
        .owner                  = THIS_MODULE,
        .supported_type_groups  = mdev_type_groups,
@@ -197,6 +274,7 @@ static const struct mdev_parent_ops vfio_ccw_mdev_ops = {
        .release                = vfio_ccw_mdev_release,
        .read                   = vfio_ccw_mdev_read,
        .write                  = vfio_ccw_mdev_write,
+       .ioctl                  = vfio_ccw_mdev_ioctl,
 };
 
 int vfio_ccw_mdev_reg(struct subchannel *sch)
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 6183789..3fd70ff 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -198,6 +198,7 @@ struct vfio_device_info {
 #define VFIO_DEVICE_FLAGS_PCI  (1 << 1)        /* vfio-pci device */
 #define VFIO_DEVICE_FLAGS_PLATFORM (1 << 2)    /* vfio-platform device */
 #define VFIO_DEVICE_FLAGS_AMBA  (1 << 3)       /* vfio-amba device */
+#define VFIO_DEVICE_FLAGS_CCW  (1 << 4)        /* vfio-ccw device */
        __u32   num_regions;    /* Max region index + 1 */
        __u32   num_irqs;       /* Max IRQ index + 1 */
 };
@@ -447,6 +448,16 @@ enum {
        VFIO_PCI_NUM_IRQS
 };
 
+/*
+ * The vfio-ccw bus driver makes use of the following fixed region.
+ * Unimplemented regions return a size of zero.
+ */
+
+enum {
+       VFIO_CCW_CONFIG_REGION_INDEX,
+       VFIO_CCW_NUM_REGIONS
+};
+
 /**
  * VFIO_DEVICE_GET_PCI_HOT_RESET_INFO - _IORW(VFIO_TYPE, VFIO_BASE + 12,
  *                                           struct vfio_pci_hot_reset_info)
-- 
2.8.4