[dpdk-dev] [PATCH 2/3] net/virtio: add device config support to vDPA

[Maxime Coquelin <maxime.coquelin@redhat.com>]

This patch introduces two virtio-user callbacks to get
and set device's config, and implements it for vDPA
backends.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 drivers/net/virtio/virtio_user/vhost.h      |  3 +
 drivers/net/virtio/virtio_user/vhost_vdpa.c | 69 +++++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/drivers/net/virtio/virtio_user/vhost.h b/drivers/net/virtio/virtio_user/vhost.h
index c49e88036d..dfbf6be033 100644
--- a/drivers/net/virtio/virtio_user/vhost.h
+++ b/drivers/net/virtio/virtio_user/vhost.h
@@ -79,6 +79,9 @@ struct virtio_user_backend_ops {
 	int (*set_vring_addr)(struct virtio_user_dev *dev, struct vhost_vring_addr *addr);
 	int (*get_status)(struct virtio_user_dev *dev, uint8_t *status);
 	int (*set_status)(struct virtio_user_dev *dev, uint8_t status);
+	int (*get_config)(struct virtio_user_dev *dev, uint8_t *data, uint32_t off, uint32_t len);
+	int (*set_config)(struct virtio_user_dev *dev, const uint8_t *data, uint32_t off,
+			uint32_t len);
 	int (*enable_qp)(struct virtio_user_dev *dev, uint16_t pair_idx, int enable);
 	int (*dma_map)(struct virtio_user_dev *dev, void *addr, uint64_t iova, size_t len);
 	int (*dma_unmap)(struct virtio_user_dev *dev, void *addr, uint64_t iova, size_t len);
diff --git a/drivers/net/virtio/virtio_user/vhost_vdpa.c b/drivers/net/virtio/virtio_user/vhost_vdpa.c
index e2d6d3504d..59bc712d48 100644
--- a/drivers/net/virtio/virtio_user/vhost_vdpa.c
+++ b/drivers/net/virtio/virtio_user/vhost_vdpa.c
@@ -41,6 +41,8 @@ struct vhost_vdpa_data {
 #define VHOST_VDPA_GET_DEVICE_ID _IOR(VHOST_VIRTIO, 0x70, __u32)
 #define VHOST_VDPA_GET_STATUS _IOR(VHOST_VIRTIO, 0x71, __u8)
 #define VHOST_VDPA_SET_STATUS _IOW(VHOST_VIRTIO, 0x72, __u8)
+#define VHOST_VDPA_GET_CONFIG _IOR(VHOST_VIRTIO, 0x73, struct vhost_vdpa_config)
+#define VHOST_VDPA_SET_CONFIG _IOW(VHOST_VIRTIO, 0x74, struct vhost_vdpa_config)
 #define VHOST_VDPA_SET_VRING_ENABLE _IOW(VHOST_VIRTIO, 0x75, struct vhost_vring_state)
 #define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
 #define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
@@ -65,6 +67,12 @@ struct vhost_iotlb_msg {
 
 #define VHOST_IOTLB_MSG_V2 0x2
 
+struct vhost_vdpa_config {
+	uint32_t off;
+	uint32_t len;
+	uint8_t buf[0];
+};
+
 struct vhost_msg {
 	uint32_t type;
 	uint32_t reserved;
@@ -440,6 +448,65 @@ vhost_vdpa_set_status(struct virtio_user_dev *dev, uint8_t status)
 	return vhost_vdpa_ioctl(data->vhostfd, VHOST_VDPA_SET_STATUS, &status);
 }
 
+static int
+vhost_vdpa_get_config(struct virtio_user_dev *dev, uint8_t *data, uint32_t off, uint32_t len)
+{
+	struct vhost_vdpa_data *vdpa_data = dev->backend_data;
+	struct vhost_vdpa_config *config;
+	int ret = 0;
+
+	config = malloc(sizeof(*config) + len);
+	if (!config) {
+		PMD_DRV_LOG(ERR, "Failed to allocate vDPA config data\n");
+		return -1;
+	}
+
+	config->off = off;
+	config->len = len;
+
+	ret = vhost_vdpa_ioctl(vdpa_data->vhostfd, VHOST_VDPA_GET_CONFIG, config);
+	if (ret) {
+		PMD_DRV_LOG(ERR, "Failed to get vDPA config (offset %x, len %x)\n", off, len);
+		ret = -1;
+		goto out;
+	}
+
+	memcpy(data, config->buf, len);
+out:
+	free(config);
+
+	return ret;
+}
+
+static int
+vhost_vdpa_set_config(struct virtio_user_dev *dev, const uint8_t *data, uint32_t off, uint32_t len)
+{
+	struct vhost_vdpa_data *vdpa_data = dev->backend_data;
+	struct vhost_vdpa_config *config;
+	int ret = 0;
+
+	config = malloc(sizeof(*config) + len);
+	if (!config) {
+		PMD_DRV_LOG(ERR, "Failed to allocate vDPA config data\n");
+		return -1;
+	}
+
+	config->off = off;
+	config->len = len;
+
+	memcpy(config->buf, data, len);
+
+	ret = vhost_vdpa_ioctl(vdpa_data->vhostfd, VHOST_VDPA_SET_CONFIG, config);
+	if (ret) {
+		PMD_DRV_LOG(ERR, "Failed to set vDPA config (offset %x, len %x)\n", off, len);
+		ret = -1;
+	}
+
+	free(config);
+
+	return ret;
+}
+
 /**
  * Set up environment to talk with a vhost vdpa backend.
  *
@@ -559,6 +626,8 @@ struct virtio_user_backend_ops virtio_ops_vdpa = {
 	.set_vring_addr = vhost_vdpa_set_vring_addr,
 	.get_status = vhost_vdpa_get_status,
 	.set_status = vhost_vdpa_set_status,
+	.get_config = vhost_vdpa_get_config,
+	.set_config = vhost_vdpa_set_config,
 	.enable_qp = vhost_vdpa_enable_queue_pair,
 	.dma_map = vhost_vdpa_dma_map_batch,
 	.dma_unmap = vhost_vdpa_dma_unmap_batch,
-- 
2.31.1