On 5/23/26 2:42 AM, Anisa Su wrote:
> From: Ira Weiny <[email protected]>
>
> Device partitions have an implied order which is made more complex by
> the addition of a dynamic partition.
>
> Remove the ram special case information calls in favor of generic calls
> with a check ahead of time to ensure the preservation of the implied
> partition order.
>
> Signed-off-by: Ira Weiny <[email protected]>
>
> ---
> Changes::
> [anisa: rebase]
> [davidlohr: core/hdm.c: return -EINVAL instead of 0 in cxl_dpa_setup
> if partitions are out of order]
> ---
> drivers/cxl/core/hdm.c | 11 ++++++++++-
> drivers/cxl/core/memdev.c | 32 +++++++++-----------------------
> drivers/cxl/cxlmem.h | 9 +++------
> drivers/cxl/mem.c | 2 +-
> 4 files changed, 23 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
> index 28974adaab75..7a5812971f8f 100644
> --- a/drivers/cxl/core/hdm.c
> +++ b/drivers/cxl/core/hdm.c
> @@ -464,6 +464,7 @@ static const char *cxl_mode_name(enum cxl_partition_mode
> mode)
> int cxl_dpa_setup(struct cxl_dev_state *cxlds, const struct cxl_dpa_info
> *info)
> {
> struct device *dev = cxlds->dev;
> + int i;
>
> guard(rwsem_write)(&cxl_rwsem.dpa);
>
> @@ -476,9 +477,17 @@ int cxl_dpa_setup(struct cxl_dev_state *cxlds, const
> struct cxl_dpa_info *info)
> return 0;
> }
>
> + /* Verify partitions are in expected order. */
> + for (i = 1; i < info->nr_partitions; i++) {
> + if (cxlds->part[i].mode < cxlds->part[i-1].mode) {
I think we need to check info->part[i].mode and not cxlds here. cxlds mode is
assigned later in this function.
DJ
> + dev_err(dev, "Partition order mismatch\n");
> + return -EINVAL;
> + }
> + }
> +
> cxlds->dpa_res = DEFINE_RES_MEM(0, info->size);
>
> - for (int i = 0; i < info->nr_partitions; i++) {
> + for (i = 0; i < info->nr_partitions; i++) {
> const struct cxl_dpa_part_info *part = &info->part[i];
> int rc;
>
> diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
> index 80e65690eb77..71602820f896 100644
> --- a/drivers/cxl/core/memdev.c
> +++ b/drivers/cxl/core/memdev.c
> @@ -75,20 +75,12 @@ 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)
> {
> struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> struct cxl_dev_state *cxlds = cxlmd->cxlds;
> - unsigned long long len = cxl_ram_size(cxlds);
> + unsigned long long len = cxl_part_size(cxlds, CXL_PARTMODE_RAM);
>
> return sysfs_emit(buf, "%#llx\n", len);
> }
> @@ -101,7 +93,7 @@ static ssize_t pmem_size_show(struct device *dev, struct
> device_attribute *attr,
> {
> struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> struct cxl_dev_state *cxlds = cxlmd->cxlds;
> - unsigned long long len = cxl_pmem_size(cxlds);
> + unsigned long long len = cxl_part_size(cxlds, CXL_PARTMODE_PMEM);
>
> return sysfs_emit(buf, "%#llx\n", len);
> }
> @@ -424,10 +416,11 @@ static struct attribute *cxl_memdev_attributes[] = {
> NULL,
> };
>
> -static struct cxl_dpa_perf *to_pmem_perf(struct cxl_dev_state *cxlds)
> +static struct cxl_dpa_perf *part_perf(struct cxl_dev_state *cxlds,
> + enum cxl_partition_mode mode)
> {
> for (int i = 0; i < cxlds->nr_partitions; i++)
> - if (cxlds->part[i].mode == CXL_PARTMODE_PMEM)
> + if (cxlds->part[i].mode == mode)
> return &cxlds->part[i].perf;
> return NULL;
> }
> @@ -438,7 +431,7 @@ static ssize_t pmem_qos_class_show(struct device *dev,
> struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> struct cxl_dev_state *cxlds = cxlmd->cxlds;
>
> - return sysfs_emit(buf, "%d\n", to_pmem_perf(cxlds)->qos_class);
> + return sysfs_emit(buf, "%d\n", part_perf(cxlds,
> CXL_PARTMODE_PMEM)->qos_class);
> }
>
> static struct device_attribute dev_attr_pmem_qos_class =
> @@ -450,20 +443,13 @@ 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)
> {
> struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> struct cxl_dev_state *cxlds = cxlmd->cxlds;
>
> - return sysfs_emit(buf, "%d\n", to_ram_perf(cxlds)->qos_class);
> + return sysfs_emit(buf, "%d\n", part_perf(cxlds,
> CXL_PARTMODE_RAM)->qos_class);
> }
>
> static struct device_attribute dev_attr_ram_qos_class =
> @@ -499,7 +485,7 @@ static umode_t cxl_ram_visible(struct kobject *kobj,
> struct attribute *a, int n)
> {
> struct device *dev = kobj_to_dev(kobj);
> struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> - struct cxl_dpa_perf *perf = to_ram_perf(cxlmd->cxlds);
> + struct cxl_dpa_perf *perf = part_perf(cxlmd->cxlds, CXL_PARTMODE_RAM);
>
> if (a == &dev_attr_ram_qos_class.attr &&
> (!perf || perf->qos_class == CXL_QOS_CLASS_INVALID))
> @@ -518,7 +504,7 @@ static umode_t cxl_pmem_visible(struct kobject *kobj,
> struct attribute *a, int n
> {
> struct device *dev = kobj_to_dev(kobj);
> struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
> - struct cxl_dpa_perf *perf = to_pmem_perf(cxlmd->cxlds);
> + struct cxl_dpa_perf *perf = part_perf(cxlmd->cxlds, CXL_PARTMODE_PMEM);
>
> if (a == &dev_attr_pmem_qos_class.attr &&
> (!perf || perf->qos_class == CXL_QOS_CLASS_INVALID))
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index cee936fb3d03..10175ca3b7ee 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -383,14 +383,11 @@ struct cxl_security_state {
>
> #define CXL_MAX_DC_PARTITIONS 8
>
> -static inline resource_size_t cxl_pmem_size(struct cxl_dev_state *cxlds)
> +static inline resource_size_t cxl_part_size(struct cxl_dev_state *cxlds,
> + enum cxl_partition_mode mode)
> {
> - /*
> - * Static PMEM may be at partition index 0 when there is no static RAM
> - * capacity.
> - */
> for (int i = 0; i < cxlds->nr_partitions; i++)
> - if (cxlds->part[i].mode == CXL_PARTMODE_PMEM)
> + if (cxlds->part[i].mode == mode)
> return resource_size(&cxlds->part[i].res);
> return 0;
> }
> diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
> index fcffe24dcb42..f19e08279ec7 100644
> --- a/drivers/cxl/mem.c
> +++ b/drivers/cxl/mem.c
> @@ -114,7 +114,7 @@ static int cxl_mem_probe(struct device *dev)
> return -ENXIO;
> }
>
> - if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) {
> + if (cxl_part_size(cxlds, CXL_PARTMODE_PMEM) &&
> IS_ENABLED(CONFIG_CXL_PMEM)) {
> rc = devm_cxl_add_nvdimm(dev, parent_port, cxlmd);
> if (rc) {
> if (rc == -ENODEV)
