Re: [PATCH 3/3] cxl/mem: Add partition information to sysfs

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Thu, 10 Jun 2021 17:22:24 -0700
<ira.weiny@intel.com> wrote:

> From: Ira Weiny <ira.weiny@intel.com>
> 
> Partitionable space is added to the ram and pmem size sysfs attributes
> but this does not show the entire story.
> 
> Add full partition information about the device under <sysfs>/partition.
> 
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> ---
>  drivers/cxl/pci.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 49 insertions(+)
> 
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index bcc2829e4475..7e4e9605e4ed 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -1226,6 +1226,42 @@ static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr,
>  static struct device_attribute dev_attr_pmem_size =
>  	__ATTR(size, 0444, pmem_size_show, NULL);
>  
> +static ssize_t part_vo_show(struct device *dev, struct device_attribute *attr,
> +			     char *buf)
> +{
> +	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> +	struct cxl_mem *cxlm = cxlmd->cxlm;
> +
> +	return sysfs_emit(buf, "%#llx\n", cxlm->volatile_cap_bytes);
> +}
> +
> +static struct device_attribute dev_attr_part_vo =
> +	__ATTR(volatile_only, 0444, part_vo_show, NULL);

With a bit of tweaking could we use DEVICE_ATTR_RO for these and have even less
boilerplate? 


> +
> +static ssize_t part_po_show(struct device *dev, struct device_attribute *attr,
> +			     char *buf)
> +{
> +	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> +	struct cxl_mem *cxlm = cxlmd->cxlm;
> +
> +	return sysfs_emit(buf, "%#llx\n", cxlm->persistent_cap_bytes);
> +}
> +
> +static struct device_attribute dev_attr_part_po =
> +	__ATTR(persistent_only, 0444, part_po_show, NULL);
> +
> +static ssize_t part_total_show(struct device *dev, struct device_attribute *attr,
> +			     char *buf)
> +{
> +	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> +	struct cxl_mem *cxlm = cxlmd->cxlm;
> +
> +	return sysfs_emit(buf, "%#llx\n", cxlm->total_cap_bytes);
> +}
> +
> +static struct device_attribute dev_attr_part_total =
> +	__ATTR(total, 0444, part_total_show, NULL);
> +
>  static struct attribute *cxl_memdev_attributes[] = {
>  	&dev_attr_firmware_version.attr,
>  	&dev_attr_payload_max.attr,
> @@ -1243,6 +1279,13 @@ static struct attribute *cxl_memdev_ram_attributes[] = {
>  	NULL,
>  };
>  
> +static struct attribute *cxl_memdev_part_attributes[] = {
> +	&dev_attr_part_vo.attr,
> +	&dev_attr_part_po.attr,
> +	&dev_attr_part_total.attr,
> +	NULL,
> +};
> +
>  static struct attribute_group cxl_memdev_attribute_group = {
>  	.attrs = cxl_memdev_attributes,
>  };
> @@ -1257,10 +1300,16 @@ static struct attribute_group cxl_memdev_pmem_attribute_group = {
>  	.attrs = cxl_memdev_pmem_attributes,
>  };
>  
> +static struct attribute_group cxl_memdev_part_attribute_group = {
> +	.name = "partition",
> +	.attrs = cxl_memdev_part_attributes,
> +};
> +
>  static const struct attribute_group *cxl_memdev_attribute_groups[] = {
>  	&cxl_memdev_attribute_group,
>  	&cxl_memdev_ram_attribute_group,
>  	&cxl_memdev_pmem_attribute_group,
> +	&cxl_memdev_part_attribute_group,
>  	NULL,
>  };
>