From 2d1b8cea119ca2bb0eec8ebb2dfb1b6c4d844ddd Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@intel.com>
Date: Sun, 23 Jan 2022 16:52:36 -0800
Subject: [PATCH 095/217] cxl/list: Emit device serial numbers

Starting with the v5.17 kernel the CXL driver emits the mandatory device
serial number for each memory device. Include it in the memory device
listing.

Link: https://lore.kernel.org/r/164298555630.3021641.3246226448369816200.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
 Documentation/cxl/cxl-list.txt | 15 +++++++++------
 cxl/json.c                     | 11 ++++++++++-
 cxl/lib/libcxl.c               | 11 +++++++++++
 cxl/lib/libcxl.sym             |  5 +++++
 cxl/lib/private.h              |  1 +
 cxl/libcxl.h                   |  1 +
 6 files changed, 37 insertions(+), 7 deletions(-)

diff --git a/Documentation/cxl/cxl-list.txt b/Documentation/cxl/cxl-list.txt
index 4d409ba..bd0207e 100644
--- a/Documentation/cxl/cxl-list.txt
+++ b/Documentation/cxl/cxl-list.txt
@@ -41,22 +41,25 @@ OPTIONS
   "ram_size":0,
 }
 
-# cxl list -m "0 mem1 2"
+# cxl list -M --memdev="0 mem3 5"
 [
   {
     "memdev":"mem0",
     "pmem_size":268435456,
-    "ram_size":0
+    "ram_size":0,
+    "serial":0
   },
   {
-    "memdev":"mem2",
+    "memdev":"mem3",
     "pmem_size":268435456,
-    "ram_size":268435456
+    "ram_size":268435456,
+    "serial":2
   },
   {
-    "memdev":"mem1",
+    "memdev":"mem5",
     "pmem_size":268435456,
-    "ram_size":268435456
+    "ram_size":268435456,
+    "serial":4
   }
 ]
 ----
diff --git a/cxl/json.c b/cxl/json.c
index 3ef9f76..d8e65df 100644
--- a/cxl/json.c
+++ b/cxl/json.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2015-2020 Intel Corporation. All rights reserved.
+// Copyright (C) 2015-2021 Intel Corporation. All rights reserved.
+#include <limits.h>
 #include <util/json.h>
 #include <uuid/uuid.h>
 #include <cxl/libcxl.h>
@@ -188,6 +189,7 @@ struct json_object *util_cxl_memdev_to_json(struct cxl_memdev *memdev,
 {
 	const char *devname = cxl_memdev_get_devname(memdev);
 	struct json_object *jdev, *jobj;
+	unsigned long long serial;
 
 	jdev = json_object_new_object();
 	if (!jdev)
@@ -210,5 +212,12 @@ struct json_object *util_cxl_memdev_to_json(struct cxl_memdev *memdev,
 		if (jobj)
 			json_object_object_add(jdev, "health", jobj);
 	}
+
+	serial = cxl_memdev_get_serial(memdev);
+	if (serial < ULLONG_MAX) {
+		jobj = util_json_object_hex(serial, flags);
+		if (jobj)
+			json_object_object_add(jdev, "serial", jobj);
+	}
 	return jdev;
 }
diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
index 3390eb9..8d3cf80 100644
--- a/cxl/lib/libcxl.c
+++ b/cxl/lib/libcxl.c
@@ -296,6 +296,12 @@ static void *add_cxl_memdev(void *parent, int id, const char *cxlmem_base)
 	if (memdev->lsa_size == ULLONG_MAX)
 		goto err_read;
 
+	sprintf(path, "%s/serial", cxlmem_base);
+	if (sysfs_read_attr(ctx, path, buf) < 0)
+		memdev->serial = ULLONG_MAX;
+	else
+		memdev->serial = strtoull(buf, NULL, 0);
+
 	memdev->dev_path = strdup(cxlmem_base);
 	if (!memdev->dev_path)
 		goto err_read;
@@ -371,6 +377,11 @@ CXL_EXPORT int cxl_memdev_get_id(struct cxl_memdev *memdev)
 	return memdev->id;
 }
 
+CXL_EXPORT unsigned long long cxl_memdev_get_serial(struct cxl_memdev *memdev)
+{
+	return memdev->serial;
+}
+
 CXL_EXPORT const char *cxl_memdev_get_devname(struct cxl_memdev *memdev)
 {
 	return devpath_to_devname(memdev->dev_path);
diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym
index 077d104..4411035 100644
--- a/cxl/lib/libcxl.sym
+++ b/cxl/lib/libcxl.sym
@@ -73,3 +73,8 @@ global:
 local:
         *;
 };
+
+LIBCXL_2 {
+global:
+	cxl_memdev_get_serial;
+} LIBCXL_1;
diff --git a/cxl/lib/private.h b/cxl/lib/private.h
index a1b8b50..28f7e16 100644
--- a/cxl/lib/private.h
+++ b/cxl/lib/private.h
@@ -31,6 +31,7 @@ struct cxl_memdev {
 	size_t lsa_size;
 	struct kmod_module *module;
 	struct cxl_nvdimm_bridge *bridge;
+	unsigned long long serial;
 };
 
 enum cxl_cmd_query_status {
diff --git a/cxl/libcxl.h b/cxl/libcxl.h
index 89d35ba..bcdede8 100644
--- a/cxl/libcxl.h
+++ b/cxl/libcxl.h
@@ -35,6 +35,7 @@ struct cxl_memdev;
 struct cxl_memdev *cxl_memdev_get_first(struct cxl_ctx *ctx);
 struct cxl_memdev *cxl_memdev_get_next(struct cxl_memdev *memdev);
 int cxl_memdev_get_id(struct cxl_memdev *memdev);
+unsigned long long cxl_memdev_get_serial(struct cxl_memdev *memdev);
 const char *cxl_memdev_get_devname(struct cxl_memdev *memdev);
 int cxl_memdev_get_major(struct cxl_memdev *memdev);
 int cxl_memdev_get_minor(struct cxl_memdev *memdev);
-- 
2.27.0