From: Jason Gunthorpe <jgg@nvidia.com>
Date: Fri, 7 Nov 2025 17:41:34 +0000 (-0400)
Subject: vfio/ccw: Convert to get_region_info_caps
X-Git-Tag: v6.19-rc1~132^2~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=973af0c40eaf5cf201d22f1cf6b50587d0138703;p=thirdparty%2Fkernel%2Flinux.git

vfio/ccw: Convert to get_region_info_caps

Remove the duplicate code and flatten the call chain.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/18-v2-2a9e24d62f1b+e10a-vfio_get_region_info_op_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
---

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 6d46e0bc76df1..a596f6013019c 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -313,10 +313,12 @@ static int vfio_ccw_mdev_get_device_info(struct vfio_ccw_private *private,
 	return 0;
 }
 
-static int vfio_ccw_mdev_get_region_info(struct vfio_ccw_private *private,
-					 struct vfio_region_info *info,
-					 unsigned long arg)
+static int vfio_ccw_mdev_ioctl_get_region_info(struct vfio_device *vdev,
+					       struct vfio_region_info *info,
+					       struct vfio_info_cap *caps)
 {
+	struct vfio_ccw_private *private =
+		container_of(vdev, struct vfio_ccw_private, vdev);
 	int i;
 
 	switch (info->index) {
@@ -328,7 +330,6 @@ static int vfio_ccw_mdev_get_region_info(struct vfio_ccw_private *private,
 		return 0;
 	default: /* all other regions are handled via capability chain */
 	{
-		struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
 		struct vfio_region_info_cap_type cap_type = {
 			.header.id = VFIO_REGION_INFO_CAP_TYPE,
 			.header.version = 1 };
@@ -351,27 +352,10 @@ static int vfio_ccw_mdev_get_region_info(struct vfio_ccw_private *private,
 		cap_type.type = private->region[i].type;
 		cap_type.subtype = private->region[i].subtype;
 
-		ret = vfio_info_add_capability(&caps, &cap_type.header,
+		ret = vfio_info_add_capability(caps, &cap_type.header,
 					       sizeof(cap_type));
 		if (ret)
 			return ret;
-
-		info->flags |= VFIO_REGION_INFO_FLAG_CAPS;
-		if (info->argsz < sizeof(*info) + caps.size) {
-			info->argsz = sizeof(*info) + caps.size;
-			info->cap_offset = 0;
-		} else {
-			vfio_info_cap_shift(&caps, sizeof(*info));
-			if (copy_to_user((void __user *)arg + sizeof(*info),
-					 caps.buf, caps.size)) {
-				kfree(caps.buf);
-				return -EFAULT;
-			}
-			info->cap_offset = sizeof(*info);
-		}
-
-		kfree(caps.buf);
-
 	}
 	}
 	return 0;
@@ -504,31 +488,6 @@ void vfio_ccw_unregister_dev_regions(struct vfio_ccw_private *private)
 	private->region = NULL;
 }
 
-static int
-vfio_ccw_mdev_ioctl_get_region_info(struct vfio_device *vdev,
-				    struct vfio_region_info __user *arg)
-{
-	struct vfio_ccw_private *private =
-		container_of(vdev, struct vfio_ccw_private, vdev);
-	struct vfio_region_info info;
-	unsigned long minsz;
-	int ret;
-
-	minsz = offsetofend(struct vfio_region_info, offset);
-
-	if (copy_from_user(&info, arg, minsz))
-		return -EFAULT;
-
-	if (info.argsz < minsz)
-		return -EINVAL;
-
-	ret = vfio_ccw_mdev_get_region_info(private, &info, arg);
-	if (ret)
-		return ret;
-
-	return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
-}
-
 static ssize_t vfio_ccw_mdev_ioctl(struct vfio_device *vdev,
 				   unsigned int cmd,
 				   unsigned long arg)
@@ -634,7 +593,7 @@ static const struct vfio_device_ops vfio_ccw_dev_ops = {
 	.read = vfio_ccw_mdev_read,
 	.write = vfio_ccw_mdev_write,
 	.ioctl = vfio_ccw_mdev_ioctl,
-	.get_region_info = vfio_ccw_mdev_ioctl_get_region_info,
+	.get_region_info_caps = vfio_ccw_mdev_ioctl_get_region_info,
 	.request = vfio_ccw_mdev_request,
 	.dma_unmap = vfio_ccw_dma_unmap,
 	.bind_iommufd = vfio_iommufd_emulated_bind,