From: Gautam Dawar <gautam.dawar@xilinx.com>
Date: Wed, 30 Mar 2022 23:33:51 +0530
Subject: vhost-vdpa: introduce uAPI to get the number of virtqueue groups
Patch-mainline: v5.19-rc1
Git-commit: 3ace88bd37436abc84906312146fe5158a469142
References: jsc#PED-1549

Follows the vDPA support for multiple address spaces, this patch
introduce uAPI for the userspace to know the number of virtqueue
groups supported by the vDPA device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-12-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/vhost/vdpa.c       |    4 ++++
 include/uapi/linux/vhost.h |    4 +++-
 2 files changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -559,6 +559,10 @@ static long vhost_vdpa_unlocked_ioctl(st
 	case VHOST_VDPA_GET_VRING_NUM:
 		r = vhost_vdpa_get_vring_num(v, argp);
 		break;
+	case VHOST_VDPA_GET_GROUP_NUM:
+		r = copy_to_user(argp, &v->vdpa->ngroups,
+				 sizeof(v->vdpa->ngroups));
+		break;
 	case VHOST_SET_LOG_BASE:
 	case VHOST_SET_LOG_FD:
 		r = -ENOIOCTLCMD;
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -145,11 +145,13 @@
 /* Get the valid iova range */
 #define VHOST_VDPA_GET_IOVA_RANGE	_IOR(VHOST_VIRTIO, 0x78, \
 					     struct vhost_vdpa_iova_range)
-
 /* Get the config size */
 #define VHOST_VDPA_GET_CONFIG_SIZE	_IOR(VHOST_VIRTIO, 0x79, __u32)
 
 /* Get the count of all virtqueues */
 #define VHOST_VDPA_GET_VQS_COUNT	_IOR(VHOST_VIRTIO, 0x80, __u32)
 
+/* Get the number of virtqueue groups. */
+#define VHOST_VDPA_GET_GROUP_NUM	_IOR(VHOST_VIRTIO, 0x81, __u32)
+
 #endif