Add an nvdimm bridge object representation internal to libcxl. A bridge object is tied to its parent memdev object, and this patch adds its first interface, which checks whether a bridge is 'active' - i.e. implying the label space on the memdev is owned by the kernel.
Cc: Dan Williams <[email protected]> Reviewed-by: Dan Williams <[email protected]> Signed-off-by: Vishal Verma <[email protected]> --- cxl/lib/private.h | 8 +++++ cxl/lib/libcxl.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++ cxl/libcxl.h | 1 + cxl/lib/libcxl.sym | 1 + 4 files changed, 83 insertions(+) diff --git a/cxl/lib/private.h b/cxl/lib/private.h index c4ed741..525c41e 100644 --- a/cxl/lib/private.h +++ b/cxl/lib/private.h @@ -10,6 +10,13 @@ #define CXL_EXPORT __attribute__ ((visibility("default"))) +struct cxl_nvdimm_bridge { + int id; + void *dev_buf; + size_t buf_len; + char *dev_path; +}; + struct cxl_memdev { int id, major, minor; void *dev_buf; @@ -23,6 +30,7 @@ struct cxl_memdev { int payload_max; size_t lsa_size; struct kmod_module *module; + struct cxl_nvdimm_bridge *bridge; }; enum cxl_cmd_query_status { diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c index def3a97..60ed646 100644 --- a/cxl/lib/libcxl.c +++ b/cxl/lib/libcxl.c @@ -45,11 +45,19 @@ struct cxl_ctx { void *private_data; }; +static void free_bridge(struct cxl_nvdimm_bridge *bridge) +{ + free(bridge->dev_buf); + free(bridge->dev_path); + free(bridge); +} + static void free_memdev(struct cxl_memdev *memdev, struct list_head *head) { if (head) list_del_from(head, &memdev->list); kmod_module_unref(memdev->module); + free_bridge(memdev->bridge); free(memdev->firmware_version); free(memdev->dev_buf); free(memdev->dev_path); @@ -205,6 +213,40 @@ CXL_EXPORT void cxl_set_log_priority(struct cxl_ctx *ctx, int priority) ctx->ctx.log_priority = priority; } +static void *add_cxl_bridge(void *parent, int id, const char *br_base) +{ + const char *devname = devpath_to_devname(br_base); + struct cxl_memdev *memdev = parent; + struct cxl_ctx *ctx = memdev->ctx; + struct cxl_nvdimm_bridge *bridge; + + dbg(ctx, "%s: bridge_base: \'%s\'\n", devname, br_base); + + bridge = calloc(1, sizeof(*bridge)); + if (!bridge) + goto err_dev; + bridge->id = id; + + bridge->dev_path = strdup(br_base); + if (!bridge->dev_path) + goto err_read; + + bridge->dev_buf = calloc(1, strlen(br_base) + 50); + if (!bridge->dev_buf) + goto err_read; + bridge->buf_len = strlen(br_base) + 50; + + memdev->bridge = bridge; + return bridge; + + err_read: + free(bridge->dev_buf); + free(bridge->dev_path); + free(bridge); + err_dev: + return NULL; +} + static void *add_cxl_memdev(void *parent, int id, const char *cxlmem_base) { const char *devname = devpath_to_devname(cxlmem_base); @@ -271,6 +313,8 @@ static void *add_cxl_memdev(void *parent, int id, const char *cxlmem_base) goto err_read; memdev->buf_len = strlen(cxlmem_base) + 50; + sysfs_device_parse(ctx, cxlmem_base, "pmem", memdev, add_cxl_bridge); + cxl_memdev_foreach(ctx, memdev_dup) if (memdev_dup->id == memdev->id) { free_memdev(memdev, NULL); @@ -362,6 +406,35 @@ CXL_EXPORT size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev) return memdev->lsa_size; } +static int is_enabled(const char *drvpath) +{ + struct stat st; + + if (lstat(drvpath, &st) < 0 || !S_ISLNK(st.st_mode)) + return 0; + else + return 1; +} + +CXL_EXPORT int cxl_memdev_nvdimm_bridge_active(struct cxl_memdev *memdev) +{ + struct cxl_ctx *ctx = cxl_memdev_get_ctx(memdev); + struct cxl_nvdimm_bridge *bridge = memdev->bridge; + char *path = bridge->dev_buf; + int len = bridge->buf_len; + + if (!bridge) + return 0; + + if (snprintf(path, len, "%s/driver", bridge->dev_path) >= len) { + err(ctx, "%s: nvdimm bridge buffer too small!\n", + cxl_memdev_get_devname(memdev)); + return 0; + } + + return is_enabled(path); +} + CXL_EXPORT void cxl_cmd_unref(struct cxl_cmd *cmd) { if (!cmd) diff --git a/cxl/libcxl.h b/cxl/libcxl.h index d3b97a1..535e349 100644 --- a/cxl/libcxl.h +++ b/cxl/libcxl.h @@ -43,6 +43,7 @@ unsigned long long cxl_memdev_get_pmem_size(struct cxl_memdev *memdev); unsigned long long cxl_memdev_get_ram_size(struct cxl_memdev *memdev); const char *cxl_memdev_get_firmware_verison(struct cxl_memdev *memdev); size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev); +int cxl_memdev_nvdimm_bridge_active(struct cxl_memdev *memdev); #define cxl_memdev_foreach(ctx, memdev) \ for (memdev = cxl_memdev_get_first(ctx); \ diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym index 858e953..f3b0c63 100644 --- a/cxl/lib/libcxl.sym +++ b/cxl/lib/libcxl.sym @@ -65,6 +65,7 @@ global: cxl_cmd_new_read_label; cxl_cmd_read_label_get_payload; cxl_memdev_get_label_size; + cxl_memdev_nvdimm_bridge_active; local: *; }; -- 2.31.1
