[PATCH -v7 2/3] x86 boot: boot parameters export via sysfs

From: Huang, Ying
Date: Tue Oct 23 2007 - 04:04:49 EST


This patch export the boot parameters via sysfs. This can be used for
debugging and kexec.

Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx>

---

Makefile_32 | 1
Makefile_64 | 1
ksysfs.c | 236 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
setup64.c | 2
setup_32.c | 2
5 files changed, 240 insertions(+), 2 deletions(-)

Index: linux-2.6/arch/x86/kernel/Makefile_64
===================================================================
--- linux-2.6.orig/arch/x86/kernel/Makefile_64 2007-10-22 09:18:08.000000000 +0800
+++ linux-2.6/arch/x86/kernel/Makefile_64 2007-10-22 14:12:53.000000000 +0800
@@ -37,6 +37,7 @@
obj-$(CONFIG_X86_VSMP) += vsmp_64.o
obj-$(CONFIG_K8_NB) += k8.o
obj-$(CONFIG_AUDIT) += audit_64.o
+obj-$(CONFIG_SYSFS) += ksysfs.o

obj-$(CONFIG_MODULES) += module_64.o
obj-$(CONFIG_PCI) += early-quirks.o
Index: linux-2.6/arch/x86/kernel/setup64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/setup64.c 2007-10-22 09:18:08.000000000 +0800
+++ linux-2.6/arch/x86/kernel/setup64.c 2007-10-22 14:12:14.000000000 +0800
@@ -24,7 +24,7 @@
#include <asm/sections.h>
#include <asm/setup.h>

-struct boot_params __initdata boot_params;
+struct boot_params boot_params;

cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE;

Index: linux-2.6/arch/x86/kernel/ksysfs.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6/arch/x86/kernel/ksysfs.c 2007-10-22 14:12:14.000000000 +0800
@@ -0,0 +1,236 @@
+/*
+ * arch/i386/ksysfs.c - architecture specific sysfs attributes in /sys/kernel
+ *
+ * Copyright (C) 2007, Intel Corp.
+ * Huang Ying <ying.huang@xxxxxxxxx>
+ *
+ * This file is released under the GPLv2
+ */
+
+#include <linux/kobject.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/init.h>
+#include <linux/stat.h>
+#include <linux/mm.h>
+
+#include <asm/setup.h>
+
+static ssize_t boot_params_version_show(struct kset *kset, char *page)
+{
+ return sprintf(page, "0x%x\n", boot_params.hdr.version);
+}
+
+static struct subsys_attribute boot_params_version_attr = {
+ .attr = {
+ .name = "version",
+ .mode = S_IRUGO,
+ },
+ .show = boot_params_version_show,
+};
+
+static struct attribute *boot_params_attrs[] = {
+ &boot_params_version_attr.attr,
+ NULL
+};
+
+static struct attribute_group boot_params_attr_group = {
+ .attrs = boot_params_attrs,
+};
+
+static ssize_t boot_params_data_read(struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t count)
+{
+ memcpy(buf, (void *)&boot_params + off, count);
+ return count;
+}
+
+static struct bin_attribute boot_params_data_attr = {
+ .attr = {
+ .name = "data",
+ .mode = S_IRUGO,
+ },
+ .read = boot_params_data_read,
+ .size = sizeof(boot_params),
+};
+
+struct setup_data_kobj
+{
+ struct kobject kobj;
+ struct setup_data *setup_data;
+ struct bin_attribute *data_attr;
+};
+
+struct setup_data_attribute {
+ struct attribute attr;
+ ssize_t (*show) (struct setup_data_kobj *setup_data_kobj, char *buf);
+};
+
+static ssize_t setup_data_type_show(struct setup_data_kobj *setup_data_kobj,
+ char *page)
+{
+ return sprintf(page, "0x%x\n", setup_data_kobj->setup_data->type);
+}
+
+static struct setup_data_attribute setup_data_type_attr = {
+ .attr = {
+ .name = "type",
+ .mode = S_IRUGO,
+ },
+ .show = setup_data_type_show,
+};
+
+static ssize_t setup_data_attr_show(struct kobject *kobj,
+ struct attribute *attr,
+ char *buf)
+{
+ struct setup_data_kobj *setup_data_kobj =
+ (struct setup_data_kobj *)kobj;
+ struct setup_data_attribute *setup_data_attr =
+ (struct setup_data_attribute *)attr;
+ ssize_t error = -EIO;
+
+ if (setup_data_attr->show)
+ error = setup_data_attr->show(setup_data_kobj, buf);
+ return error;
+}
+
+static void setup_data_kobj_release(struct kobject *kobj)
+{
+ struct setup_data_kobj *setup_data_kobj =
+ (struct setup_data_kobj *)kobj;
+ kfree(setup_data_kobj->data_attr);
+ kfree(setup_data_kobj);
+}
+
+static struct sysfs_ops setup_data_attr_ops = {
+ .show = setup_data_attr_show,
+};
+
+static struct attribute *setup_data_default_attrs[] = {
+ &setup_data_type_attr.attr,
+ NULL,
+};
+
+static struct kobj_type ktype_setup_data = {
+ .release = &setup_data_kobj_release,
+ .sysfs_ops = &setup_data_attr_ops,
+ .default_attrs = setup_data_default_attrs,
+};
+
+static ssize_t setup_data_data_read(struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct setup_data_kobj *setup_data_kobj =
+ (struct setup_data_kobj *)kobj;
+ memcpy(buf, setup_data_kobj->setup_data->data + off, count);
+ return count;
+}
+
+decl_subsys(boot_params, NULL, NULL);
+decl_subsys(setup_data, &ktype_setup_data, NULL);
+
+static int __init setup_data_create_kobj(struct setup_data *setup_data,
+ const char *name)
+{
+ struct setup_data_kobj *setup_data_kobj;
+ struct bin_attribute *data_attr;
+ int error;
+
+ setup_data_kobj = kzalloc(sizeof(struct setup_data_kobj), GFP_KERNEL);
+ if (!setup_data_kobj) {
+ error = -ENOMEM;
+ goto err_return;
+ }
+ setup_data_kobj->setup_data = setup_data;
+ kobject_set_name(&setup_data_kobj->kobj, "%s", name);
+ kobj_set_kset_s(setup_data_kobj, setup_data_subsys);
+ error = kobject_register(&setup_data_kobj->kobj);
+ if (error) {
+ kfree(setup_data_kobj);
+ goto err_return;
+ }
+ data_attr = kzalloc(sizeof(struct bin_attribute), GFP_KERNEL);
+ if (!data_attr) {
+ error = -ENOMEM;
+ goto err_unregister;
+ }
+ setup_data_kobj->data_attr = data_attr;
+ data_attr->attr.name = "data";
+ data_attr->attr.mode = S_IRUGO;
+ data_attr->read = setup_data_data_read;
+ data_attr->size = setup_data->len;
+ error = sysfs_create_bin_file(&setup_data_kobj->kobj,
+ data_attr);
+ if (error)
+ goto err_unregister;
+ return 0;
+err_unregister:
+ kobject_unregister(&setup_data_kobj->kobj);
+err_return:
+ return error;
+}
+
+static void __init setup_data_kobjs_del(void)
+{
+ struct kobject *kobj;
+
+ spin_lock(&setup_data_subsys.list_lock);
+ list_for_each_entry(kobj, &setup_data_subsys.list, entry)
+ kobject_unregister(kobj);
+ spin_unlock(&setup_data_subsys.list_lock);
+}
+
+static int __init boot_params_ksysfs_init(void)
+{
+ int error;
+ struct setup_data *setup_data;
+ int n = 0;
+ char buf[8];
+
+ kobj_set_kset_s(&boot_params_subsys, kernel_subsys);
+ error = subsystem_register(&boot_params_subsys);
+ if (error)
+ goto err_return;
+ error = sysfs_create_group(&boot_params_subsys.kobj,
+ &boot_params_attr_group);
+ if (error)
+ goto err_boot_params_subsys_unregister;
+ error = sysfs_create_bin_file(&boot_params_subsys.kobj,
+ &boot_params_data_attr);
+ if (error)
+ goto err_boot_params_subsys_unregister;
+ kobj_set_kset_s(&setup_data_subsys, boot_params_subsys);
+ error = subsystem_register(&setup_data_subsys);
+ if (error)
+ goto err_boot_params_subsys_unregister;
+ for (setup_data = __va(boot_params.hdr.setup_data);
+ setup_data != __va(0);
+ setup_data = __va(setup_data->next)) {
+ sprintf(buf, "%d", n++);
+ error = setup_data_create_kobj(setup_data, buf);
+ if (error)
+ goto err_setup_data_kobjs_del;
+ }
+ return 0;
+err_setup_data_kobjs_del:
+ setup_data_kobjs_del();
+ subsystem_unregister(&setup_data_subsys);
+err_boot_params_subsys_unregister:
+ subsystem_unregister(&boot_params_subsys);
+err_return:
+ return error;
+}
+
+static int __init arch_ksysfs_init(void)
+{
+ int error;
+
+ error = boot_params_ksysfs_init();
+
+ return error;
+}
+
+arch_initcall(arch_ksysfs_init);
Index: linux-2.6/arch/x86/kernel/Makefile_32
===================================================================
--- linux-2.6.orig/arch/x86/kernel/Makefile_32 2007-10-22 09:18:08.000000000 +0800
+++ linux-2.6/arch/x86/kernel/Makefile_32 2007-10-22 14:13:06.000000000 +0800
@@ -41,6 +41,7 @@
obj-$(CONFIG_HPET_TIMER) += hpet.o
obj-$(CONFIG_K8_NB) += k8.o
obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o
+obj-$(CONFIG_SYSFS) += ksysfs.o

obj-$(CONFIG_VMI) += vmi_32.o vmiclock_32.o
obj-$(CONFIG_PARAVIRT) += paravirt_32.o
Index: linux-2.6/arch/x86/kernel/setup_32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/setup_32.c 2007-10-22 14:09:25.000000000 +0800
+++ linux-2.6/arch/x86/kernel/setup_32.c 2007-10-22 14:12:14.000000000 +0800
@@ -125,7 +125,7 @@

static char __initdata command_line[COMMAND_LINE_SIZE];

-struct boot_params __initdata boot_params;
+struct boot_params boot_params;

#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
struct edd edd;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/