cxl: Cleanup partition size and perf helpers

Now that the 'struct cxl_dpa_partition' array contains both size and
performance information, all paths that iterate over that information
can use a loop rather than hard-code 'ram' and 'pmem' lookups.

Remove, or reduce the scope of the temporary helpers that bridged the
pre-'struct cxl_dpa_partition' state of the code to the post-'struct
cxl_dpa_partition' state.

- to_{ram,pmem}_perf(): scope reduced to just sysfs_emit + is_visible()
  helpers

- to_{ram,pmem}_res(): fold into their only users cxl_{ram,pmem}_size()

- cxl_ram_size(): scope reduced to ram_size_show() (Note,
  cxl_pmem_size() also used to gate nvdimm registration)

In short, memdev sysfs ABI already made the promise that 0-sized
partitions will show for memdevs, but that can be avoided for future
partitions by using dynamic sysfs group visibility (new relative to when
the partition ABI first shipped upstream).

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alejandro Lucero <alucerop@amd.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Alejandro Lucero <alucerop@amd.com>
Link: https://patch.msgid.link/173864307519.668823.10800104022426067621.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index 615cbd861f66..63c6c681125d 100644
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -75,6 +75,14 @@ static ssize_t label_storage_size_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(label_storage_size);
 
+static resource_size_t cxl_ram_size(struct cxl_dev_state *cxlds)
+{
+	/* Static RAM is only expected at partition 0. */
+	if (cxlds->part[0].mode != CXL_PARTMODE_RAM)
+		return 0;
+	return resource_size(&cxlds->part[0].res);
+}
+
 static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr,
 			     char *buf)
 {
@@ -399,6 +407,14 @@ static struct attribute *cxl_memdev_attributes[] = {
 	NULL,
 };
 
+static struct cxl_dpa_perf *to_pmem_perf(struct cxl_dev_state *cxlds)
+{
+	for (int i = 0; i < cxlds->nr_partitions; i++)
+		if (cxlds->part[i].mode == CXL_PARTMODE_PMEM)
+			return &cxlds->part[i].perf;
+	return NULL;
+}
+
 static ssize_t pmem_qos_class_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
@@ -417,6 +433,13 @@ static struct attribute *cxl_memdev_pmem_attributes[] = {
 	NULL,
 };
 
+static struct cxl_dpa_perf *to_ram_perf(struct cxl_dev_state *cxlds)
+{
+	if (cxlds->part[0].mode != CXL_PARTMODE_RAM)
+		return NULL;
+	return &cxlds->part[0].perf;
+}
+
 static ssize_t ram_qos_class_show(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {