Subject: + efi-export-efi-runtime-memory-mapping-to-sysfs.patch added to -mm tree
To: dyoung@xxxxxxxxxx,James.Bottomley@xxxxxxxxxxxxxxxxxxxxx,bp@xxxxxxx,ebiederm@xxxxxxxxxxxx,greg@xxxxxxxxx,horms@xxxxxxxxxxxx,hpa@xxxxxxxxx,matt@xxxxxxxxxxxxxxxxx,mingo@xxxxxxx,mjg59@xxxxxxxxxxxxx,tglx@xxxxxxxxxxxxx,toshi.kani@xxxxxx,vgoyal@xxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Tue, 10 Dec 2013 15:23:18 -0800
The patch titled
Subject: efi: export efi runtime memory mapping to sysfs
has been added to the -mm tree. Its filename is
efi-export-efi-runtime-memory-mapping-to-sysfs.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/efi-export-efi-runtime-memory-mapping-to-sysfs.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/efi-export-efi-runtime-memory-mapping-to-sysfs.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Dave Young <dyoung@xxxxxxxxxx>
Subject: efi: export efi runtime memory mapping to sysfs
kexec kernel will need exactly same mapping for efi runtime memory ranges.
Thus here export the runtime ranges mapping to sysfs, kexec-tools will
assemble them and pass to 2nd kernel via setup_data.
Introduce a new directory /sys/firmware/efi/runtime-map Just like
/sys/firmware/memmap. Containing below attribute in each file of that
directory: attribute num_pages phys_addr type virt_addr
Signed-off-by: Dave Young <dyoung@xxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Greg KH <greg@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxx>
Cc: Matthew Garrett <mjg59@xxxxxxxxxxxxx>
Cc: Simon Horman <horms@xxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Toshi Kani <toshi.kani@xxxxxx>
Cc: Vivek Goyal <vgoyal@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-firmware-efi-runtime-map | 36 ++
arch/x86/platform/efi/efi.c | 28 +
drivers/firmware/efi/Kconfig | 11
drivers/firmware/efi/Makefile | 1
drivers/firmware/efi/efi.c | 4
drivers/firmware/efi/runtime-map.c | 176 ++++++++++
include/linux/efi.h | 6
7 files changed, 261 insertions(+), 1 deletion(-)
diff -puN /dev/null Documentation/ABI/testing/sysfs-firmware-efi-runtime-map
--- /dev/null
+++ a/Documentation/ABI/testing/sysfs-firmware-efi-runtime-map
@@ -0,0 +1,36 @@
+What: /sys/firmware/efi/runtime-map/
+Date: December 2013
+Contact: Dave Young <dyoung@xxxxxxxxxx>
+Description:
+ Switching efi runtime services to virtual mode requires
+ that all efi memory ranges which have the runtime attribute
+ bit set to be mapped to virtual addresses.
+
+ The efi runtime services can only be switched to virtual
+ mode once without rebooting. The kexec kernel must maintain
+ the same physical to virtual address mappings as the first
+ kernel. The mappings are exported to sysfs so userspace tools
+ can reassemble them and pass them into the kexec kernel.
+
+ /sys/firmware/efi/runtime-map/ is the directory the kernel
+ exports that information in.
+
+ subdirectories are named with the number of the memory range:
+
+ /sys/firmware/efi/runtime-map/0
+ /sys/firmware/efi/runtime-map/1
+ /sys/firmware/efi/runtime-map/2
+ /sys/firmware/efi/runtime-map/3
+ ...
+
+ Each subdirectory contains five files:
+
+ attribute : The attributes of the memory range.
+ num_pages : The size of the memory range in pages.
+ phys_addr : The physical address of the memory range.
+ type : The type of the memory range.
+ virt_addr : The virtual address of the memory range.
+
+ Above values are all hexadecimal numbers with the '0x' prefix.
+
+Users: Kexec
diff -puN arch/x86/platform/efi/efi.c~efi-export-efi-runtime-memory-mapping-to-sysfs arch/x86/platform/efi/efi.c
--- a/arch/x86/platform/efi/efi.c~efi-export-efi-runtime-memory-mapping-to-sysfs
+++ a/arch/x86/platform/efi/efi.c
@@ -76,6 +76,9 @@ static __initdata efi_config_table_type_
{NULL_GUID, NULL, NULL},
};
+void *efi_runtime_map;
+int nr_efi_runtime_map;
+
/*
* Returns 1 if 'facility' is enabled, 0 otherwise.
*/
@@ -810,6 +813,19 @@ static void __init efi_merge_regions(voi
}
}
+static int __init save_runtime_map(efi_memory_desc_t *md, int idx)
+{
+ void *p;
+ p = krealloc(efi_runtime_map, (idx + 1) * memmap.desc_size, GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ efi_runtime_map = p;
+ memcpy(efi_runtime_map + idx * memmap.desc_size, md, memmap.desc_size);
+
+ return 0;
+}
+
/*
* Map efi memory ranges for runtime serivce and update new_memmap with virtual
* addresses.
@@ -820,6 +836,7 @@ static void * __init efi_map_regions(int
void *p, *tmp, *new_memmap = NULL;
unsigned long size;
u64 end, systab;
+ int err = 0;
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
@@ -848,10 +865,21 @@ static void * __init efi_map_regions(int
new_memmap = tmp;
memcpy(new_memmap + (*count * memmap.desc_size), md,
memmap.desc_size);
+ if (md->type != EFI_BOOT_SERVICES_CODE &&
+ md->type != EFI_BOOT_SERVICES_DATA) {
+ err = save_runtime_map(md, nr_efi_runtime_map);
+ if (err)
+ goto out_save_runtime;
+ nr_efi_runtime_map++;
+ }
(*count)++;
}
return new_memmap;
+out_save_runtime:
+ kfree(efi_runtime_map);
+ nr_efi_runtime_map = 0;
+ efi_runtime_map = NULL;
out_krealloc:
kfree(new_memmap);
return NULL;
diff -puN drivers/firmware/efi/Kconfig~efi-export-efi-runtime-memory-mapping-to-sysfs drivers/firmware/efi/Kconfig
--- a/drivers/firmware/efi/Kconfig~efi-export-efi-runtime-memory-mapping-to-sysfs
+++ a/drivers/firmware/efi/Kconfig
@@ -39,4 +39,15 @@ config EFI_VARS_PSTORE_DEFAULT_DISABLE
config UEFI_CPER
def_bool n
+config EFI_RUNTIME_MAP
+ bool "Export efi runtime maps to sysfs" if EXPERT
+ depends on X86 && EFI && KEXEC
+ default y
+ help
+ Export efi runtime memory maps to /sys/firmware/efi/runtime-map.
+ That memory map is used for example by kexec to set up efi virtual
+ mapping the 2nd kernel, but can also be used for debugging purposes.
+
+ See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map.
+
endmenu
diff -puN drivers/firmware/efi/Makefile~efi-export-efi-runtime-memory-mapping-to-sysfs drivers/firmware/efi/Makefile
--- a/drivers/firmware/efi/Makefile~efi-export-efi-runtime-memory-mapping-to-sysfs
+++ a/drivers/firmware/efi/Makefile
@@ -5,3 +5,4 @@ obj-y += efi.o vars.o
obj-$(CONFIG_EFI_VARS) += efivars.o
obj-$(CONFIG_EFI_VARS_PSTORE) += efi-pstore.o
obj-$(CONFIG_UEFI_CPER) += cper.o
+obj-$(CONFIG_EFI_RUNTIME_MAP) += runtime-map.o
diff -puN drivers/firmware/efi/efi.c~efi-export-efi-runtime-memory-mapping-to-sysfs drivers/firmware/efi/efi.c
--- a/drivers/firmware/efi/efi.c~efi-export-efi-runtime-memory-mapping-to-sysfs
+++ a/drivers/firmware/efi/efi.c
@@ -38,7 +38,8 @@ struct efi __read_mostly efi = {
};
EXPORT_SYMBOL(efi);
-static struct kobject *efi_kobj;
+struct kobject *efi_kobj;
+EXPORT_SYMBOL_GPL(efi_kobj);
static struct kobject *efivars_kobj;
/*
@@ -183,6 +184,7 @@ err_unregister:
generic_ops_unregister();
err_put:
kobject_put(efi_kobj);
+ efi_kobj = NULL;
return error;
}
diff -puN /dev/null drivers/firmware/efi/runtime-map.c
--- /dev/null
+++ a/drivers/firmware/efi/runtime-map.c
@@ -0,0 +1,176 @@
+/*
+ * linux/drivers/efi/runtime-map.c
+ * Copyright (C) 2013 Red Hat, Inc., Dave Young <dyoung@xxxxxxxxxx>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/efi.h>
+#include <linux/slab.h>
+
+#include <asm/setup.h>
+
+struct efi_runtime_map_entry {
+ efi_memory_desc_t md;
+ struct kobject kobj; /* kobject for each entry */
+};
+
+static struct efi_runtime_map_entry **map_entries;
+
+struct map_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct efi_runtime_map_entry *entry, char *buf);
+};
+
+static inline struct map_attribute *to_map_attr(struct attribute *attr)
+{
+ return container_of(attr, struct map_attribute, attr);
+}
+
+static ssize_t type_show(struct efi_runtime_map_entry *entry, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "0x%x\n", entry->md.type);
+}
+
+#define EFI_RUNTIME_FIELD(var) entry->md.var
+
+#define EFI_RUNTIME_U64_ATTR_SHOW(name) \
+static ssize_t name##_show(struct efi_runtime_map_entry *entry, char *buf) \
+{ \
+ return snprintf(buf, PAGE_SIZE, "0x%llx\n", EFI_RUNTIME_FIELD(name)); \
+}
+
+EFI_RUNTIME_U64_ATTR_SHOW(phys_addr);
+EFI_RUNTIME_U64_ATTR_SHOW(virt_addr);
+EFI_RUNTIME_U64_ATTR_SHOW(num_pages);
+EFI_RUNTIME_U64_ATTR_SHOW(attribute);
+
+static inline struct efi_runtime_map_entry *to_map_entry(struct kobject *kobj)
+{
+ return container_of(kobj, struct efi_runtime_map_entry, kobj);
+}
+
+static ssize_t map_attr_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ struct efi_runtime_map_entry *entry = to_map_entry(kobj);
+ struct map_attribute *map_attr = to_map_attr(attr);
+
+ return map_attr->show(entry, buf);
+}
+
+static struct map_attribute map_type_attr = __ATTR_RO(type);
+static struct map_attribute map_phys_addr_attr = __ATTR_RO(phys_addr);
+static struct map_attribute map_virt_addr_attr = __ATTR_RO(virt_addr);
+static struct map_attribute map_num_pages_attr = __ATTR_RO(num_pages);
+static struct map_attribute map_attribute_attr = __ATTR_RO(attribute);
+
+/*
+ * These are default attributes that are added for every memmap entry.
+ */
+static struct attribute *def_attrs[] = {
+ &map_type_attr.attr,
+ &map_phys_addr_attr.attr,
+ &map_virt_addr_attr.attr,
+ &map_num_pages_attr.attr,
+ &map_attribute_attr.attr,
+ NULL
+};
+
+static const struct sysfs_ops map_attr_ops = {
+ .show = map_attr_show,
+};
+
+static void map_release(struct kobject *kobj)
+{
+ struct efi_runtime_map_entry *entry;
+
+ entry = to_map_entry(kobj);
+ kfree(entry);
+}
+
+static struct kobj_type __refdata map_ktype = {
+ .sysfs_ops = &map_attr_ops,
+ .default_attrs = def_attrs,
+ .release = map_release,
+};
+
+static struct kset *map_kset;
+
+static struct efi_runtime_map_entry *add_sysfs_runtime_map_entry(int nr)
+{
+ int ret;
+ struct efi_runtime_map_entry *entry;
+ struct efi_info *e = &boot_params.efi_info;
+
+ if (!map_kset) {
+ map_kset = kset_create_and_add("runtime-map", NULL,
+ efi_kobj);
+ if (!map_kset)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ kset_unregister(map_kset);
+ return entry;
+ }
+
+ memcpy(&entry->md, efi_runtime_map + nr * e->efi_memdesc_size,
+ sizeof(efi_memory_desc_t));
+
+ kobject_init(&entry->kobj, &map_ktype);
+ entry->kobj.kset = map_kset;
+ ret = kobject_add(&entry->kobj, NULL, "%d", nr);
+ if (ret) {
+ kobject_put(&entry->kobj);
+ kset_unregister(map_kset);
+ return ERR_PTR(ret);
+ }
+
+ return entry;
+}
+
+static int __init efi_runtime_map_init(void)
+{
+ int i, j, ret = 0;
+ struct efi_runtime_map_entry *entry;
+
+ if (!efi_kobj)
+ return 0;
+
+ if (!efi_runtime_map)
+ return 0;
+
+ map_entries = kzalloc(nr_efi_runtime_map * sizeof(entry), GFP_KERNEL);
+ if (!map_entries) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ for (i = 0; i < nr_efi_runtime_map; i++) {
+ entry = add_sysfs_runtime_map_entry(i);
+ if (IS_ERR(entry)) {
+ ret = PTR_ERR(entry);
+ goto out_add_entry;
+ }
+ *(map_entries + i) = entry;
+ }
+
+ return 0;
+out_add_entry:
+ for (j = i - 1; j > 0; j--) {
+ entry = *(map_entries + j);
+ kobject_put(&entry->kobj);
+ }
+ if (map_kset)
+ kset_unregister(map_kset);
+out:
+ return ret;
+}
+
+subsys_initcall(efi_runtime_map_init);
diff -puN include/linux/efi.h~efi-export-efi-runtime-memory-mapping-to-sysfs include/linux/efi.h
--- a/include/linux/efi.h~efi-export-efi-runtime-memory-mapping-to-sysfs
+++ a/include/linux/efi.h
@@ -876,4 +876,10 @@ int efivars_sysfs_init(void);
#endif /* CONFIG_EFI_VARS */
+#ifdef CONFIG_EFI_RUNTIME_MAP
+extern void *efi_runtime_map;
+extern int nr_efi_runtime_map;
+extern struct kobject *efi_kobj;
+#endif
+
#endif /* _LINUX_EFI_H */
_
Patches currently in -mm which might be from dyoung@xxxxxxxxxx are
kexec-migrate-to-reboot-cpu.patch
x86-mm-sparse-warning-fix-for-early_memremap.patch
efi-use-early_memremap-and-early_memunmap.patch
efi-remove-unused-variables-in-__map_region.patch
efi-add-a-wrapper-function-efi_map_region_fixed.patch
efi-reserve-boot-service-fix.patch
efi-cleanup-efi_enter_virtual_mode-function.patch
efi-export-more-efi-table-variable-to-sysfs.patch
efi-export-efi-runtime-memory-mapping-to-sysfs.patch
efi-pass-kexec-necessary-efi-data-via-setup_data.patch
efi-only-print-saved-efi-runtime-maps-instead-of-all-memmap-ranges-for-kexec.patch
x86-add-xloadflags-bit-for-efi-runtime-support-on-kexec.patch
x86-export-x86-boot_params-to-sysfs.patch
x86-reserve-setup_data-ranges-late-after-parsing-memmap-cmdline.patch
x86-kdebugfs-do-not-use-__va-for-getting-setup_data-virt-addr.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
