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

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

On 6/16/21 2:26 PM, Xia, Chenbo wrote:
> Hi Maxime,
> 
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Sent: Tuesday, June 8, 2021 10:14 PM
>> To: dev@dpdk.org; Xia, Chenbo <chenbo.xia@intel.com>; amorenoz@redhat.com;
>> david.marchand@redhat.com
>> Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Subject: [PATCH 2/3] net/virtio: add device config support to vDPA
>>
>> 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");
> 
> No need to add '\n'. And same for below three 'PMD_DRV_LOG'

Yes, it is unecessary.

>> +		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",
> 
> Better add '0x' here as it will be friendly to user 😊

Indeed, fixing it in v2.

>> 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);
> 
> Ditto


Fixed in v2.

Thanks,
Maxime

> Thanks,
> Chenbo
> 
>> +		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
>