Re: [PATCH RFC v2 17/18] tools/testing/cxl: Add DC Regions to mock mem data

[Dave Jiang]

On 8/28/23 22:21, Ira Weiny wrote:
> To test DC regions the mock memory devices will need to store
> information about the regions and manage fake extent data.
>
> Define mock_dc_region information within the mock memory data.  Add
> sysfs entries on the mock device to inject and delete extents.
>
> The inject format is <start>:<length>:<tag>
> The delete format is <start>
>
> Add DC mailbox commands to the CEL and implement those commands.
>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>

Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
>   tools/testing/cxl/test/mem.c | 449 +++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 449 insertions(+)
>
> diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
> index 6a036c8d215d..d6041a2145c5 100644
> --- a/tools/testing/cxl/test/mem.c
> +++ b/tools/testing/cxl/test/mem.c
> @@ -18,6 +18,7 @@
>   #define FW_SLOTS 3
>   #define DEV_SIZE SZ_2G
>   #define EFFECT(x) (1U << x)
> +#define BASE_DYNAMIC_CAP_DPA DEV_SIZE
>   
>   #define MOCK_INJECT_DEV_MAX 8
>   #define MOCK_INJECT_TEST_MAX 128
> @@ -89,6 +90,22 @@ static struct cxl_cel_entry mock_cel[] = {
>   		.effect = cpu_to_le16(EFFECT(CONF_CHANGE_COLD_RESET) |
>   				      EFFECT(CONF_CHANGE_IMMEDIATE)),
>   	},
> +	{
> +		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_DC_CONFIG),
> +		.effect = CXL_CMD_EFFECT_NONE,
> +	},
> +	{
> +		.opcode = cpu_to_le16(CXL_MBOX_OP_GET_DC_EXTENT_LIST),
> +		.effect = CXL_CMD_EFFECT_NONE,
> +	},
> +	{
> +		.opcode = cpu_to_le16(CXL_MBOX_OP_ADD_DC_RESPONSE),
> +		.effect = cpu_to_le16(EFFECT(CONF_CHANGE_IMMEDIATE)),
> +	},
> +	{
> +		.opcode = cpu_to_le16(CXL_MBOX_OP_RELEASE_DC),
> +		.effect = cpu_to_le16(EFFECT(CONF_CHANGE_IMMEDIATE)),
> +	},
>   };
>   
>   /* See CXL 2.0 Table 181 Get Health Info Output Payload */
> @@ -147,6 +164,7 @@ struct mock_event_store {
>   	u32 ev_status;
>   };
>   
> +#define NUM_MOCK_DC_REGIONS 2
>   struct cxl_mockmem_data {
>   	void *lsa;
>   	void *fw;
> @@ -161,6 +179,10 @@ struct cxl_mockmem_data {
>   	struct mock_event_store mes;
>   	u8 event_buf[SZ_4K];
>   	u64 timestamp;
> +	struct cxl_dc_region_config dc_regions[NUM_MOCK_DC_REGIONS];
> +	u32 dc_ext_generation;
> +	struct xarray dc_extents;
> +	struct xarray dc_accepted_exts;
>   };
>   
>   static struct mock_event_log *event_find_log(struct device *dev, int log_type)
> @@ -529,6 +551,98 @@ static void cxl_mock_event_trigger(struct device *dev)
>   	cxl_mem_get_event_records(mes->mds, mes->ev_status);
>   }
>   
> +static int devm_add_extent(struct device *dev, u64 start, u64 length,
> +			   const char *tag)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	struct cxl_dc_extent_data *extent;
> +
> +	extent = devm_kzalloc(dev, sizeof(*extent), GFP_KERNEL);
> +	if (!extent) {
> +		dev_dbg(dev, "Failed to allocate extent\n");
> +		return -ENOMEM;
> +	}
> +	extent->dpa_start = start;
> +	extent->length = length;
> +	memcpy(extent->tag, tag, min(sizeof(extent->tag), strlen(tag)));
> +
> +	if (xa_insert(&mdata->dc_extents, start, extent, GFP_KERNEL)) {
> +		devm_kfree(dev, extent);
> +		dev_err(dev, "Failed xarry insert %llx\n", start);
> +		return -EINVAL;
> +	}
> +	mdata->dc_ext_generation++;
> +
> +	return 0;
> +}
> +
> +static int dc_accept_extent(struct device *dev, u64 start)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +
> +	dev_dbg(dev, "Accepting extent 0x%llx\n", start);
> +	return xa_insert(&mdata->dc_accepted_exts, start, (void *)start,
> +			 GFP_KERNEL);
> +}
> +
> +static void release_dc_ext(void *md)
> +{
> +	struct cxl_mockmem_data *mdata = md;
> +
> +	xa_destroy(&mdata->dc_extents);
> +	xa_destroy(&mdata->dc_accepted_exts);
> +}
> +
> +static int cxl_mock_dc_region_setup(struct device *dev)
> +{
> +#define DUMMY_EXT_OFFSET SZ_256M
> +#define DUMMY_EXT_LENGTH SZ_256M
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	u64 base_dpa = BASE_DYNAMIC_CAP_DPA;
> +	u32 dsmad_handle = 0xFADE;
> +	u64 decode_length = SZ_2G;
> +	u64 block_size = SZ_512;
> +	/* For testing make this smaller than decode length */
> +	u64 length = SZ_1G;
> +	int rc;
> +
> +	xa_init(&mdata->dc_extents);
> +	xa_init(&mdata->dc_accepted_exts);
> +
> +	rc = devm_add_action_or_reset(dev, release_dc_ext, mdata);
> +	if (rc)
> +		return rc;
> +
> +	for (int i = 0; i < NUM_MOCK_DC_REGIONS; i++) {
> +		struct cxl_dc_region_config *conf = &mdata->dc_regions[i];
> +
> +		dev_dbg(dev, "Creating DC region DC%d DPA:%llx LEN:%llx\n",
> +			i, base_dpa, length);
> +
> +		conf->region_base = cpu_to_le64(base_dpa);
> +		conf->region_decode_length = cpu_to_le64(decode_length /
> +						CXL_CAPACITY_MULTIPLIER);
> +		conf->region_length = cpu_to_le64(length);
> +		conf->region_block_size = cpu_to_le64(block_size);
> +		conf->region_dsmad_handle = cpu_to_le32(dsmad_handle);
> +		dsmad_handle++;
> +
> +		/* Pretend we have some previous accepted extents */
> +		rc = devm_add_extent(dev, base_dpa + DUMMY_EXT_OFFSET,
> +				     DUMMY_EXT_LENGTH, "CXL-TEST");
> +		if (rc)
> +			return rc;
> +
> +		rc = dc_accept_extent(dev, base_dpa + DUMMY_EXT_OFFSET);
> +		if (rc)
> +			return rc;
> +
> +		base_dpa += decode_length;
> +	}
> +
> +	return 0;
> +}
> +
>   static int mock_gsl(struct cxl_mbox_cmd *cmd)
>   {
>   	if (cmd->size_out < sizeof(mock_gsl_payload))
> @@ -1315,6 +1429,148 @@ static int mock_activate_fw(struct cxl_mockmem_data *mdata,
>   	return -EINVAL;
>   }
>   
> +static int mock_get_dc_config(struct device *dev,
> +			      struct cxl_mbox_cmd *cmd)
> +{
> +	struct cxl_mbox_get_dc_config *dc_config = cmd->payload_in;
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	u8 region_requested, region_start_idx, region_ret_cnt;
> +	struct cxl_mbox_dynamic_capacity *resp;
> +
> +	region_requested = dc_config->region_count;
> +	if (NUM_MOCK_DC_REGIONS < region_requested)
> +		region_requested = NUM_MOCK_DC_REGIONS;
> +
> +	if (cmd->size_out < struct_size(resp, region, region_requested))
> +		return -EINVAL;
> +
> +	memset(cmd->payload_out, 0, cmd->size_out);
> +	resp = cmd->payload_out;
> +
> +	region_start_idx = dc_config->start_region_index;
> +	region_ret_cnt = 0;
> +	for (int i = 0; i < NUM_MOCK_DC_REGIONS; i++) {
> +		if (i >= region_start_idx) {
> +			memcpy(&resp->region[region_ret_cnt],
> +				&mdata->dc_regions[i],
> +				sizeof(resp->region[region_ret_cnt]));
> +			region_ret_cnt++;
> +		}
> +	}
> +	resp->avail_region_count = region_ret_cnt;
> +
> +	dev_dbg(dev, "Returning %d dc regions\n", region_ret_cnt);
> +	return 0;
> +}
> +
> +
> +static int mock_get_dc_extent_list(struct device *dev,
> +				   struct cxl_mbox_cmd *cmd)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	struct cxl_mbox_get_dc_extent *get = cmd->payload_in;
> +	struct cxl_mbox_dc_extents *resp = cmd->payload_out;
> +	u32 total_avail = 0, total_ret = 0;
> +	struct cxl_dc_extent_data *ext;
> +	u32 ext_count, start_idx;
> +	unsigned long i;
> +
> +	ext_count = le32_to_cpu(get->extent_cnt);
> +	start_idx = le32_to_cpu(get->start_extent_index);
> +
> +	memset(resp, 0, sizeof(*resp));
> +
> +	/*
> +	 * Total available needs to be calculated and returned regardless of
> +	 * how many can actually be returned.
> +	 */
> +	xa_for_each(&mdata->dc_extents, i, ext)
> +		total_avail++;
> +
> +	if (start_idx > total_avail)
> +		return -EINVAL;
> +
> +	xa_for_each(&mdata->dc_extents, i, ext) {
> +		if (total_ret >= ext_count)
> +			break;
> +
> +		if (total_ret >= start_idx) {
> +			resp->extent[total_ret].start_dpa =
> +						cpu_to_le64(ext->dpa_start);
> +			resp->extent[total_ret].length =
> +						cpu_to_le64(ext->length);
> +			memcpy(&resp->extent[total_ret].tag, ext->tag,
> +					sizeof(resp->extent[total_ret]));
> +			resp->extent[total_ret].shared_extn_seq =
> +					cpu_to_le16(ext->shared_extent_seq);
> +			total_ret++;
> +		}
> +	}
> +
> +	resp->ret_extent_cnt = cpu_to_le32(total_ret);
> +	resp->total_extent_cnt = cpu_to_le32(total_avail);
> +	resp->extent_list_num = cpu_to_le32(mdata->dc_ext_generation);
> +
> +	dev_dbg(dev, "Returning %d extents of %d total\n",
> +		total_ret, total_avail);
> +
> +	return 0;
> +}
> +
> +static int mock_add_dc_response(struct device *dev,
> +				struct cxl_mbox_cmd *cmd)
> +{
> +	struct cxl_mbox_dc_response *req = cmd->payload_in;
> +	u32 list_size = le32_to_cpu(req->extent_list_size);
> +
> +	for (int i = 0; i < list_size; i++) {
> +		u64 start = le64_to_cpu(req->extent_list[i].dpa_start);
> +		int rc;
> +
> +		dev_dbg(dev, "Extent 0x%llx accepted by HOST\n", start);
> +		rc = dc_accept_extent(dev, start);
> +		if (rc)
> +			return rc;
> +	}
> +
> +	return 0;
> +}
> +
> +static int dc_delete_extent(struct device *dev, unsigned long long start)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	void *ext;
> +
> +	dev_dbg(dev, "Deleting extent at %llx\n", start);
> +
> +	ext = xa_erase(&mdata->dc_extents, start);
> +	if (!ext) {
> +		dev_err(dev, "No extent found at %llx\n", start);
> +		return -EINVAL;
> +	}
> +	devm_kfree(dev, ext);
> +	mdata->dc_ext_generation++;
> +
> +	return 0;
> +}
> +
> +static int mock_dc_release(struct device *dev,
> +			   struct cxl_mbox_cmd *cmd)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	struct cxl_mbox_dc_response *req = cmd->payload_in;
> +	u32 list_size = le32_to_cpu(req->extent_list_size);
> +
> +	for (int i = 0; i < list_size; i++) {
> +		u64 start = le64_to_cpu(req->extent_list[i].dpa_start);
> +
> +		dev_dbg(dev, "Extent 0x%llx released by HOST\n", start);
> +		xa_erase(&mdata->dc_accepted_exts, start);
> +	}
> +
> +	return 0;
> +}
> +
>   static int cxl_mock_mbox_send(struct cxl_memdev_state *mds,
>   			      struct cxl_mbox_cmd *cmd)
>   {
> @@ -1399,6 +1655,18 @@ static int cxl_mock_mbox_send(struct cxl_memdev_state *mds,
>   	case CXL_MBOX_OP_ACTIVATE_FW:
>   		rc = mock_activate_fw(mdata, cmd);
>   		break;
> +	case CXL_MBOX_OP_GET_DC_CONFIG:
> +		rc = mock_get_dc_config(dev, cmd);
> +		break;
> +	case CXL_MBOX_OP_GET_DC_EXTENT_LIST:
> +		rc = mock_get_dc_extent_list(dev, cmd);
> +		break;
> +	case CXL_MBOX_OP_ADD_DC_RESPONSE:
> +		rc = mock_add_dc_response(dev, cmd);
> +		break;
> +	case CXL_MBOX_OP_RELEASE_DC:
> +		rc = mock_dc_release(dev, cmd);
> +		break;
>   	default:
>   		break;
>   	}
> @@ -1467,6 +1735,10 @@ static int __cxl_mock_mem_probe(struct platform_device *pdev)
>   		return -ENOMEM;
>   	dev_set_drvdata(dev, mdata);
>   
> +	rc = cxl_mock_dc_region_setup(dev);
> +	if (rc)
> +		return rc;
> +
>   	mdata->lsa = vmalloc(LSA_SIZE);
>   	if (!mdata->lsa)
>   		return -ENOMEM;
> @@ -1515,6 +1787,10 @@ static int __cxl_mock_mem_probe(struct platform_device *pdev)
>   	if (rc)
>   		return rc;
>   
> +	rc = cxl_dev_dynamic_capacity_identify(mds);
> +	if (rc)
> +		return rc;
> +
>   	rc = cxl_mem_create_range_info(mds);
>   	if (rc)
>   		return rc;
> @@ -1528,6 +1804,10 @@ static int __cxl_mock_mem_probe(struct platform_device *pdev)
>   	if (IS_ERR(cxlmd))
>   		return PTR_ERR(cxlmd);
>   
> +	rc = cxl_dev_get_dynamic_capacity_extents(mds);
> +	if (rc)
> +		return rc;
> +
>   	rc = cxl_memdev_setup_fw_upload(mds);
>   	if (rc)
>   		return rc;
> @@ -1669,10 +1949,179 @@ static ssize_t fw_buf_checksum_show(struct device *dev,
>   
>   static DEVICE_ATTR_RO(fw_buf_checksum);
>   
> +/* Returns if the proposed extent is valid */
> +static bool new_extent_valid(struct device *dev, size_t new_start,
> +			     size_t new_len)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	struct cxl_dc_extent_data *extent;
> +	size_t new_end, i;
> +
> +	if (!new_len)
> +		return -EINVAL;
> +
> +	new_end = new_start + new_len;
> +
> +	dev_dbg(dev, "New extent %zx-%zx\n", new_start, new_end);
> +
> +	/* Overlap with other extent? */
> +	xa_for_each(&mdata->dc_extents, i, extent) {
> +		size_t ext_end = extent->dpa_start + extent->length;
> +
> +		if (extent->dpa_start <= new_start && new_start < ext_end) {
> +			dev_err(dev, "Extent overlap: Start %llu ?<= %zx ?<= %zx\n",
> +				extent->dpa_start, new_start, ext_end);
> +			return false;
> +		}
> +		if (extent->dpa_start <= new_end && new_end < ext_end) {
> +			dev_err(dev, "Extent overlap: End %llx ?<= %zx ?<= %zx\n",
> +				extent->dpa_start, new_end, ext_end);
> +			return false;
> +		}
> +	}
> +
> +	/* Ensure it is in a region and is valid for that regions block size */
> +	for (int i = 0; i < NUM_MOCK_DC_REGIONS; i++) {
> +		struct cxl_dc_region_config *dc_region = &mdata->dc_regions[i];
> +		size_t reg_start, reg_end;
> +
> +		reg_start = le64_to_cpu(dc_region->region_base);
> +		reg_end = le64_to_cpu(dc_region->region_length);
> +		reg_end += reg_start;
> +
> +		dev_dbg(dev, "Region %d: %zx-%zx\n", i, reg_start, reg_end);
> +
> +		if (reg_start >= new_start && new_end < reg_end) {
> +			u64 block_size = le64_to_cpu(dc_region->region_block_size);
> +
> +			if (new_start % block_size || new_len % block_size) {
> +				dev_err(dev, "Extent not aligned to block size: start %zx; len %zx; block_size 0x%llx\n",
> +					new_start, new_len, block_size);
> +				return false;
> +			}
> +
> +			dev_dbg(dev, "Extent in region %d\n", i);
> +			return true;
> +		}
> +	}
> +
> +	return false;
> +}
> +
> +/*
> + * Format <start>:<length>:<tag>
> + *
> + * start and length must be a multiple of the configured region block size.
> + * Tag can be any string up to 16 bytes.
> + *
> + * Extents must be exclusive of other extents
> + */
> +static ssize_t dc_inject_extent_store(struct device *dev,
> +				      struct device_attribute *attr,
> +				      const char *buf, size_t count)
> +{
> +	char *start_str __free(kfree) = kstrdup(buf, GFP_KERNEL);
> +	unsigned long long start, length;
> +	char *len_str, *tag_str;
> +	size_t buf_len = count;
> +	int rc;
> +
> +	if (!start_str)
> +		return -ENOMEM;
> +
> +	len_str = strnchr(start_str, buf_len, ':');
> +	if (!len_str) {
> +		dev_err(dev, "Extent failed to find len_str: %s\n", start_str);
> +		return -EINVAL;
> +	}
> +
> +	*len_str = '\0';
> +	len_str += 1;
> +	buf_len -= strlen(start_str);
> +
> +	tag_str = strnchr(len_str, buf_len, ':');
> +	if (!tag_str) {
> +		dev_err(dev, "Extent failed to find tag_str: %s\n", len_str);
> +		return -EINVAL;
> +	}
> +	*tag_str = '\0';
> +	tag_str += 1;
> +
> +	if (kstrtoull(start_str, 0, &start)) {
> +		dev_err(dev, "Extent failed to parse start: %s\n", start_str);
> +		return -EINVAL;
> +	}
> +	if (kstrtoull(len_str, 0, &length)) {
> +		dev_err(dev, "Extent failed to parse length: %s\n", len_str);
> +		return -EINVAL;
> +	}
> +
> +	if (!new_extent_valid(dev, start, length))
> +		return -EINVAL;
> +
> +	rc = devm_add_extent(dev, start, length, tag_str);
> +	if (rc)
> +		return rc;
> +
> +	return count;
> +}
> +static DEVICE_ATTR_WO(dc_inject_extent);
> +
> +static ssize_t dc_del_extent_store(struct device *dev,
> +				   struct device_attribute *attr,
> +				   const char *buf, size_t count)
> +{
> +	unsigned long long start;
> +	int rc;
> +
> +	if (kstrtoull(buf, 0, &start)) {
> +		dev_err(dev, "Extent failed to parse start value\n");
> +		return -EINVAL;
> +	}
> +
> +	rc = dc_delete_extent(dev, start);
> +	if (rc)
> +		return rc;
> +
> +	return count;
> +}
> +static DEVICE_ATTR_WO(dc_del_extent);
> +
> +static ssize_t dc_force_del_extent_store(struct device *dev,
> +					 struct device_attribute *attr,
> +					 const char *buf, size_t count)
> +{
> +	struct cxl_mockmem_data *mdata = dev_get_drvdata(dev);
> +	unsigned long long start;
> +	void *ext;
> +	int rc;
> +
> +	if (kstrtoull(buf, 0, &start)) {
> +		dev_err(dev, "Extent failed to parse start value\n");
> +		return -EINVAL;
> +	}
> +
> +	ext = xa_erase(&mdata->dc_accepted_exts, start);
> +	if (ext)
> +		dev_dbg(dev, "Forcing remove of accepted extent: %llx\n",
> +			start);
> +
> +	dev_dbg(dev, "Forcing delete of extent at %llx\n", start);
> +	rc = dc_delete_extent(dev, start);
> +	if (rc)
> +		return rc;
> +
> +	return count;
> +}
> +static DEVICE_ATTR_WO(dc_force_del_extent);
> +
>   static struct attribute *cxl_mock_mem_attrs[] = {
>   	&dev_attr_security_lock.attr,
>   	&dev_attr_event_trigger.attr,
>   	&dev_attr_fw_buf_checksum.attr,
> +	&dev_attr_dc_inject_extent.attr,
> +	&dev_attr_dc_del_extent.attr,
> +	&dev_attr_dc_force_del_extent.attr,
>   	NULL
>   };
>   ATTRIBUTE_GROUPS(cxl_mock_mem);