[PATCH 03/10] vDPA: report virtio-block block-size to user space

[Zhu Lingshan <lingshan.zhu@intel.com>]

This commit allows reporting the block size of a
virtio-block device to user space.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vdpa/vdpa.c       | 18 ++++++++++++++++++
 include/uapi/linux/vdpa.h |  1 +
 2 files changed, 19 insertions(+)

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index ee1472d32b0d..cc8f41d24c9c 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -970,6 +970,21 @@ vdpa_dev_blk_seg_size_config_fill(struct sk_buff *msg, u64 features,
 	return nla_put_u32(msg, VDPA_ATTR_DEV_BLK_CFG_SEG_SIZE, val_u32);
 }
 
+/* fill the block size*/
+static int
+vdpa_dev_blk_block_size_config_fill(struct sk_buff *msg, u64 features,
+				    const struct virtio_blk_config *config)
+{
+	u32 val_u32;
+
+	if ((features & BIT_ULL(VIRTIO_BLK_F_BLK_SIZE)) == 0)
+		return 0;
+
+	val_u32 = __virtio32_to_cpu(true, config->blk_size);
+
+	return nla_put_u32(msg, VDPA_ATTR_DEV_BLK_CFG_BLK_SIZE, val_u32);
+}
+
 static int vdpa_dev_blk_config_fill(struct vdpa_device *vdev,
 				    struct sk_buff *msg)
 {
@@ -990,6 +1005,9 @@ static int vdpa_dev_blk_config_fill(struct vdpa_device *vdev,
 	if (vdpa_dev_blk_seg_size_config_fill(msg, features_device, &config))
 		return -EMSGSIZE;
 
+	if (vdpa_dev_blk_block_size_config_fill(msg, features_device, &config))
+		return -EMSGSIZE;
+
 	return 0;
 }
 
diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h
index 586bce3c906a..f3baf7ea7d6d 100644
--- a/include/uapi/linux/vdpa.h
+++ b/include/uapi/linux/vdpa.h
@@ -58,6 +58,7 @@ enum vdpa_attr {
 
 	VDPA_ATTR_DEV_BLK_CFG_CAPACITY,		/* u64 */
 	VDPA_ATTR_DEV_BLK_CFG_SEG_SIZE,		/* u32 */
+	VDPA_ATTR_DEV_BLK_CFG_BLK_SIZE,		/* u32 */
 
 	/* new attributes must be added above here */
 	VDPA_ATTR_MAX,
-- 
2.39.3