linux/drivers/firmware/efi/efi.c
Ard Biesheuvel c05f8f92b7 efivar/ssdt: Don't iterate over EFI vars if no SSDT override was specified
The kernel command line option efivar_ssdt= allows the name to be
specified of an EFI variable containing an ACPI SSDT table that should
be loaded into memory by the OS, and treated as if it was provided by
the firmware.

Currently, that code will always iterate over the EFI variables and
compare each name with the provided name, even if the command line
option wasn't set to begin with.

So bail early when no variable name was provided. This works around a
boot regression on the 2012 Mac Pro, as reported by Scott.

Tested-by: Scott Talbert <swt@techie.net>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org> # v4.9+
Cc: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: Dave Young <dyoung@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Matthew Garrett <mjg59@google.com>
Cc: Octavian Purdila <octavian.purdila@intel.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Cc: linux-integrity@vger.kernel.org
Fixes: 475fb4e8b2 ("efi / ACPI: load SSTDs from EFI variables")
Link: https://lkml.kernel.org/r/20191002165904.8819-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-07 15:24:35 +02:00

1079 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* efi.c - EFI subsystem
*
* Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
* Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
* Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
*
* This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
* allowing the efivarfs to be mounted or the efivars module to be loaded.
* The existance of /sys/firmware/efi may also be used by userspace to
* determine that the system supports EFI.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/efi.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/io.h>
#include <linux/kexec.h>
#include <linux/platform_device.h>
#include <linux/random.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/ucs2_string.h>
#include <linux/memblock.h>
#include <linux/security.h>
#include <asm/early_ioremap.h>
struct efi __read_mostly efi = {
.mps = EFI_INVALID_TABLE_ADDR,
.acpi = EFI_INVALID_TABLE_ADDR,
.acpi20 = EFI_INVALID_TABLE_ADDR,
.smbios = EFI_INVALID_TABLE_ADDR,
.smbios3 = EFI_INVALID_TABLE_ADDR,
.boot_info = EFI_INVALID_TABLE_ADDR,
.hcdp = EFI_INVALID_TABLE_ADDR,
.uga = EFI_INVALID_TABLE_ADDR,
.fw_vendor = EFI_INVALID_TABLE_ADDR,
.runtime = EFI_INVALID_TABLE_ADDR,
.config_table = EFI_INVALID_TABLE_ADDR,
.esrt = EFI_INVALID_TABLE_ADDR,
.properties_table = EFI_INVALID_TABLE_ADDR,
.mem_attr_table = EFI_INVALID_TABLE_ADDR,
.rng_seed = EFI_INVALID_TABLE_ADDR,
.tpm_log = EFI_INVALID_TABLE_ADDR,
.tpm_final_log = EFI_INVALID_TABLE_ADDR,
.mem_reserve = EFI_INVALID_TABLE_ADDR,
};
EXPORT_SYMBOL(efi);
struct mm_struct efi_mm = {
.mm_rb = RB_ROOT,
.mm_users = ATOMIC_INIT(2),
.mm_count = ATOMIC_INIT(1),
.mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
.page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
.mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
.cpu_bitmap = { [BITS_TO_LONGS(NR_CPUS)] = 0},
};
struct workqueue_struct *efi_rts_wq;
static bool disable_runtime;
static int __init setup_noefi(char *arg)
{
disable_runtime = true;
return 0;
}
early_param("noefi", setup_noefi);
bool efi_runtime_disabled(void)
{
return disable_runtime;
}
static int __init parse_efi_cmdline(char *str)
{
if (!str) {
pr_warn("need at least one option\n");
return -EINVAL;
}
if (parse_option_str(str, "debug"))
set_bit(EFI_DBG, &efi.flags);
if (parse_option_str(str, "noruntime"))
disable_runtime = true;
return 0;
}
early_param("efi", parse_efi_cmdline);
struct kobject *efi_kobj;
/*
* Let's not leave out systab information that snuck into
* the efivars driver
* Note, do not add more fields in systab sysfs file as it breaks sysfs
* one value per file rule!
*/
static ssize_t systab_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
char *str = buf;
if (!kobj || !buf)
return -EINVAL;
if (efi.mps != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "MPS=0x%lx\n", efi.mps);
if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
if (efi.acpi != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
/*
* If both SMBIOS and SMBIOS3 entry points are implemented, the
* SMBIOS3 entry point shall be preferred, so we list it first to
* let applications stop parsing after the first match.
*/
if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
if (efi.smbios != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
if (efi.uga != EFI_INVALID_TABLE_ADDR)
str += sprintf(str, "UGA=0x%lx\n", efi.uga);
return str - buf;
}
static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
#define EFI_FIELD(var) efi.var
#define EFI_ATTR_SHOW(name) \
static ssize_t name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
}
EFI_ATTR_SHOW(fw_vendor);
EFI_ATTR_SHOW(runtime);
EFI_ATTR_SHOW(config_table);
static ssize_t fw_platform_size_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
}
static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
static struct kobj_attribute efi_attr_fw_platform_size =
__ATTR_RO(fw_platform_size);
static struct attribute *efi_subsys_attrs[] = {
&efi_attr_systab.attr,
&efi_attr_fw_vendor.attr,
&efi_attr_runtime.attr,
&efi_attr_config_table.attr,
&efi_attr_fw_platform_size.attr,
NULL,
};
static umode_t efi_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int n)
{
if (attr == &efi_attr_fw_vendor.attr) {
if (efi_enabled(EFI_PARAVIRT) ||
efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
return 0;
} else if (attr == &efi_attr_runtime.attr) {
if (efi.runtime == EFI_INVALID_TABLE_ADDR)
return 0;
} else if (attr == &efi_attr_config_table.attr) {
if (efi.config_table == EFI_INVALID_TABLE_ADDR)
return 0;
}
return attr->mode;
}
static const struct attribute_group efi_subsys_attr_group = {
.attrs = efi_subsys_attrs,
.is_visible = efi_attr_is_visible,
};
static struct efivars generic_efivars;
static struct efivar_operations generic_ops;
static int generic_ops_register(void)
{
generic_ops.get_variable = efi.get_variable;
generic_ops.set_variable = efi.set_variable;
generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
generic_ops.get_next_variable = efi.get_next_variable;
generic_ops.query_variable_store = efi_query_variable_store;
return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
}
static void generic_ops_unregister(void)
{
efivars_unregister(&generic_efivars);
}
#if IS_ENABLED(CONFIG_ACPI)
#define EFIVAR_SSDT_NAME_MAX 16
static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
static int __init efivar_ssdt_setup(char *str)
{
int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
if (ret)
return ret;
if (strlen(str) < sizeof(efivar_ssdt))
memcpy(efivar_ssdt, str, strlen(str));
else
pr_warn("efivar_ssdt: name too long: %s\n", str);
return 0;
}
__setup("efivar_ssdt=", efivar_ssdt_setup);
static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
unsigned long name_size, void *data)
{
struct efivar_entry *entry;
struct list_head *list = data;
char utf8_name[EFIVAR_SSDT_NAME_MAX];
int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
ucs2_as_utf8(utf8_name, name, limit - 1);
if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
return 0;
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
if (!entry)
return 0;
memcpy(entry->var.VariableName, name, name_size);
memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
efivar_entry_add(entry, list);
return 0;
}
static __init int efivar_ssdt_load(void)
{
LIST_HEAD(entries);
struct efivar_entry *entry, *aux;
unsigned long size;
void *data;
int ret;
if (!efivar_ssdt[0])
return 0;
ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
list_for_each_entry_safe(entry, aux, &entries, list) {
pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
&entry->var.VendorGuid);
list_del(&entry->list);
ret = efivar_entry_size(entry, &size);
if (ret) {
pr_err("failed to get var size\n");
goto free_entry;
}
data = kmalloc(size, GFP_KERNEL);
if (!data) {
ret = -ENOMEM;
goto free_entry;
}
ret = efivar_entry_get(entry, NULL, &size, data);
if (ret) {
pr_err("failed to get var data\n");
goto free_data;
}
ret = acpi_load_table(data);
if (ret) {
pr_err("failed to load table: %d\n", ret);
goto free_data;
}
goto free_entry;
free_data:
kfree(data);
free_entry:
kfree(entry);
}
return ret;
}
#else
static inline int efivar_ssdt_load(void) { return 0; }
#endif
/*
* We register the efi subsystem with the firmware subsystem and the
* efivars subsystem with the efi subsystem, if the system was booted with
* EFI.
*/
static int __init efisubsys_init(void)
{
int error;
if (!efi_enabled(EFI_BOOT))
return 0;
/*
* Since we process only one efi_runtime_service() at a time, an
* ordered workqueue (which creates only one execution context)
* should suffice all our needs.
*/
efi_rts_wq = alloc_ordered_workqueue("efi_rts_wq", 0);
if (!efi_rts_wq) {
pr_err("Creating efi_rts_wq failed, EFI runtime services disabled.\n");
clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
return 0;
}
/* We register the efi directory at /sys/firmware/efi */
efi_kobj = kobject_create_and_add("efi", firmware_kobj);
if (!efi_kobj) {
pr_err("efi: Firmware registration failed.\n");
return -ENOMEM;
}
error = generic_ops_register();
if (error)
goto err_put;
if (efi_enabled(EFI_RUNTIME_SERVICES))
efivar_ssdt_load();
error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
if (error) {
pr_err("efi: Sysfs attribute export failed with error %d.\n",
error);
goto err_unregister;
}
error = efi_runtime_map_init(efi_kobj);
if (error)
goto err_remove_group;
/* and the standard mountpoint for efivarfs */
error = sysfs_create_mount_point(efi_kobj, "efivars");
if (error) {
pr_err("efivars: Subsystem registration failed.\n");
goto err_remove_group;
}
return 0;
err_remove_group:
sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
err_unregister:
generic_ops_unregister();
err_put:
kobject_put(efi_kobj);
return error;
}
subsys_initcall(efisubsys_init);
/*
* Find the efi memory descriptor for a given physical address. Given a
* physical address, determine if it exists within an EFI Memory Map entry,
* and if so, populate the supplied memory descriptor with the appropriate
* data.
*/
int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
{
efi_memory_desc_t *md;
if (!efi_enabled(EFI_MEMMAP)) {
pr_err_once("EFI_MEMMAP is not enabled.\n");
return -EINVAL;
}
if (!out_md) {
pr_err_once("out_md is null.\n");
return -EINVAL;
}
for_each_efi_memory_desc(md) {
u64 size;
u64 end;
size = md->num_pages << EFI_PAGE_SHIFT;
end = md->phys_addr + size;
if (phys_addr >= md->phys_addr && phys_addr < end) {
memcpy(out_md, md, sizeof(*out_md));
return 0;
}
}
return -ENOENT;
}
/*
* Calculate the highest address of an efi memory descriptor.
*/
u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
{
u64 size = md->num_pages << EFI_PAGE_SHIFT;
u64 end = md->phys_addr + size;
return end;
}
void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
/**
* efi_mem_reserve - Reserve an EFI memory region
* @addr: Physical address to reserve
* @size: Size of reservation
*
* Mark a region as reserved from general kernel allocation and
* prevent it being released by efi_free_boot_services().
*
* This function should be called drivers once they've parsed EFI
* configuration tables to figure out where their data lives, e.g.
* efi_esrt_init().
*/
void __init efi_mem_reserve(phys_addr_t addr, u64 size)
{
if (!memblock_is_region_reserved(addr, size))
memblock_reserve(addr, size);
/*
* Some architectures (x86) reserve all boot services ranges
* until efi_free_boot_services() because of buggy firmware
* implementations. This means the above memblock_reserve() is
* superfluous on x86 and instead what it needs to do is
* ensure the @start, @size is not freed.
*/
efi_arch_mem_reserve(addr, size);
}
static __initdata efi_config_table_type_t common_tables[] = {
{ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
{ACPI_TABLE_GUID, "ACPI", &efi.acpi},
{HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
{MPS_TABLE_GUID, "MPS", &efi.mps},
{SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
{SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
{UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
{EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
{EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
{EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
{LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
{LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log},
{LINUX_EFI_TPM_FINAL_LOG_GUID, "TPMFinalLog", &efi.tpm_final_log},
{LINUX_EFI_MEMRESERVE_TABLE_GUID, "MEMRESERVE", &efi.mem_reserve},
#ifdef CONFIG_EFI_RCI2_TABLE
{DELLEMC_EFI_RCI2_TABLE_GUID, NULL, &rci2_table_phys},
#endif
{NULL_GUID, NULL, NULL},
};
static __init int match_config_table(efi_guid_t *guid,
unsigned long table,
efi_config_table_type_t *table_types)
{
int i;
if (table_types) {
for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
if (!efi_guidcmp(*guid, table_types[i].guid)) {
*(table_types[i].ptr) = table;
if (table_types[i].name)
pr_cont(" %s=0x%lx ",
table_types[i].name, table);
return 1;
}
}
}
return 0;
}
int __init efi_config_parse_tables(void *config_tables, int count, int sz,
efi_config_table_type_t *arch_tables)
{
void *tablep;
int i;
tablep = config_tables;
pr_info("");
for (i = 0; i < count; i++) {
efi_guid_t guid;
unsigned long table;
if (efi_enabled(EFI_64BIT)) {
u64 table64;
guid = ((efi_config_table_64_t *)tablep)->guid;
table64 = ((efi_config_table_64_t *)tablep)->table;
table = table64;
#ifndef CONFIG_64BIT
if (table64 >> 32) {
pr_cont("\n");
pr_err("Table located above 4GB, disabling EFI.\n");
return -EINVAL;
}
#endif
} else {
guid = ((efi_config_table_32_t *)tablep)->guid;
table = ((efi_config_table_32_t *)tablep)->table;
}
if (!match_config_table(&guid, table, common_tables))
match_config_table(&guid, table, arch_tables);
tablep += sz;
}
pr_cont("\n");
set_bit(EFI_CONFIG_TABLES, &efi.flags);
if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
struct linux_efi_random_seed *seed;
u32 size = 0;
seed = early_memremap(efi.rng_seed, sizeof(*seed));
if (seed != NULL) {
size = seed->size;
early_memunmap(seed, sizeof(*seed));
} else {
pr_err("Could not map UEFI random seed!\n");
}
if (size > 0) {
seed = early_memremap(efi.rng_seed,
sizeof(*seed) + size);
if (seed != NULL) {
pr_notice("seeding entropy pool\n");
add_device_randomness(seed->bits, seed->size);
early_memunmap(seed, sizeof(*seed) + size);
} else {
pr_err("Could not map UEFI random seed!\n");
}
}
}
if (efi_enabled(EFI_MEMMAP))
efi_memattr_init();
efi_tpm_eventlog_init();
/* Parse the EFI Properties table if it exists */
if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
efi_properties_table_t *tbl;
tbl = early_memremap(efi.properties_table, sizeof(*tbl));
if (tbl == NULL) {
pr_err("Could not map Properties table!\n");
return -ENOMEM;
}
if (tbl->memory_protection_attribute &
EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
set_bit(EFI_NX_PE_DATA, &efi.flags);
early_memunmap(tbl, sizeof(*tbl));
}
if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) {
unsigned long prsv = efi.mem_reserve;
while (prsv) {
struct linux_efi_memreserve *rsv;
u8 *p;
int i;
/*
* Just map a full page: that is what we will get
* anyway, and it permits us to map the entire entry
* before knowing its size.
*/
p = early_memremap(ALIGN_DOWN(prsv, PAGE_SIZE),
PAGE_SIZE);
if (p == NULL) {
pr_err("Could not map UEFI memreserve entry!\n");
return -ENOMEM;
}
rsv = (void *)(p + prsv % PAGE_SIZE);
/* reserve the entry itself */
memblock_reserve(prsv, EFI_MEMRESERVE_SIZE(rsv->size));
for (i = 0; i < atomic_read(&rsv->count); i++) {
memblock_reserve(rsv->entry[i].base,
rsv->entry[i].size);
}
prsv = rsv->next;
early_memunmap(p, PAGE_SIZE);
}
}
return 0;
}
int __init efi_config_init(efi_config_table_type_t *arch_tables)
{
void *config_tables;
int sz, ret;
if (efi.systab->nr_tables == 0)
return 0;
if (efi_enabled(EFI_64BIT))
sz = sizeof(efi_config_table_64_t);
else
sz = sizeof(efi_config_table_32_t);
/*
* Let's see what config tables the firmware passed to us.
*/
config_tables = early_memremap(efi.systab->tables,
efi.systab->nr_tables * sz);
if (config_tables == NULL) {
pr_err("Could not map Configuration table!\n");
return -ENOMEM;
}
ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
arch_tables);
early_memunmap(config_tables, efi.systab->nr_tables * sz);
return ret;
}
#ifdef CONFIG_EFI_VARS_MODULE
static int __init efi_load_efivars(void)
{
struct platform_device *pdev;
if (!efi_enabled(EFI_RUNTIME_SERVICES))
return 0;
pdev = platform_device_register_simple("efivars", 0, NULL, 0);
return PTR_ERR_OR_ZERO(pdev);
}
device_initcall(efi_load_efivars);
#endif
#ifdef CONFIG_EFI_PARAMS_FROM_FDT
#define UEFI_PARAM(name, prop, field) \
{ \
{ name }, \
{ prop }, \
offsetof(struct efi_fdt_params, field), \
FIELD_SIZEOF(struct efi_fdt_params, field) \
}
struct params {
const char name[32];
const char propname[32];
int offset;
int size;
};
static __initdata struct params fdt_params[] = {
UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
};
static __initdata struct params xen_fdt_params[] = {
UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
};
#define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params)
static __initdata struct {
const char *uname;
const char *subnode;
struct params *params;
} dt_params[] = {
{ "hypervisor", "uefi", xen_fdt_params },
{ "chosen", NULL, fdt_params },
};
struct param_info {
int found;
void *params;
const char *missing;
};
static int __init __find_uefi_params(unsigned long node,
struct param_info *info,
struct params *params)
{
const void *prop;
void *dest;
u64 val;
int i, len;
for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
prop = of_get_flat_dt_prop(node, params[i].propname, &len);
if (!prop) {
info->missing = params[i].name;
return 0;
}
dest = info->params + params[i].offset;
info->found++;
val = of_read_number(prop, len / sizeof(u32));
if (params[i].size == sizeof(u32))
*(u32 *)dest = val;
else
*(u64 *)dest = val;
if (efi_enabled(EFI_DBG))
pr_info(" %s: 0x%0*llx\n", params[i].name,
params[i].size * 2, val);
}
return 1;
}
static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
int depth, void *data)
{
struct param_info *info = data;
int i;
for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
const char *subnode = dt_params[i].subnode;
if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
info->missing = dt_params[i].params[0].name;
continue;
}
if (subnode) {
int err = of_get_flat_dt_subnode_by_name(node, subnode);
if (err < 0)
return 0;
node = err;
}
return __find_uefi_params(node, info, dt_params[i].params);
}
return 0;
}
int __init efi_get_fdt_params(struct efi_fdt_params *params)
{
struct param_info info;
int ret;
pr_info("Getting EFI parameters from FDT:\n");
info.found = 0;
info.params = params;
ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
if (!info.found)
pr_info("UEFI not found.\n");
else if (!ret)
pr_err("Can't find '%s' in device tree!\n",
info.missing);
return ret;
}
#endif /* CONFIG_EFI_PARAMS_FROM_FDT */
static __initdata char memory_type_name[][20] = {
"Reserved",
"Loader Code",
"Loader Data",
"Boot Code",
"Boot Data",
"Runtime Code",
"Runtime Data",
"Conventional Memory",
"Unusable Memory",
"ACPI Reclaim Memory",
"ACPI Memory NVS",
"Memory Mapped I/O",
"MMIO Port Space",
"PAL Code",
"Persistent Memory",
};
char * __init efi_md_typeattr_format(char *buf, size_t size,
const efi_memory_desc_t *md)
{
char *pos;
int type_len;
u64 attr;
pos = buf;
if (md->type >= ARRAY_SIZE(memory_type_name))
type_len = snprintf(pos, size, "[type=%u", md->type);
else
type_len = snprintf(pos, size, "[%-*s",
(int)(sizeof(memory_type_name[0]) - 1),
memory_type_name[md->type]);
if (type_len >= size)
return buf;
pos += type_len;
size -= type_len;
attr = md->attribute;
if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
EFI_MEMORY_NV |
EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
snprintf(pos, size, "|attr=0x%016llx]",
(unsigned long long)attr);
else
snprintf(pos, size,
"|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
attr & EFI_MEMORY_NV ? "NV" : "",
attr & EFI_MEMORY_XP ? "XP" : "",
attr & EFI_MEMORY_RP ? "RP" : "",
attr & EFI_MEMORY_WP ? "WP" : "",
attr & EFI_MEMORY_RO ? "RO" : "",
attr & EFI_MEMORY_UCE ? "UCE" : "",
attr & EFI_MEMORY_WB ? "WB" : "",
attr & EFI_MEMORY_WT ? "WT" : "",
attr & EFI_MEMORY_WC ? "WC" : "",
attr & EFI_MEMORY_UC ? "UC" : "");
return buf;
}
/*
* IA64 has a funky EFI memory map that doesn't work the same way as
* other architectures.
*/
#ifndef CONFIG_IA64
/*
* efi_mem_attributes - lookup memmap attributes for physical address
* @phys_addr: the physical address to lookup
*
* Search in the EFI memory map for the region covering
* @phys_addr. Returns the EFI memory attributes if the region
* was found in the memory map, 0 otherwise.
*/
u64 efi_mem_attributes(unsigned long phys_addr)
{
efi_memory_desc_t *md;
if (!efi_enabled(EFI_MEMMAP))
return 0;
for_each_efi_memory_desc(md) {
if ((md->phys_addr <= phys_addr) &&
(phys_addr < (md->phys_addr +
(md->num_pages << EFI_PAGE_SHIFT))))
return md->attribute;
}
return 0;
}
/*
* efi_mem_type - lookup memmap type for physical address
* @phys_addr: the physical address to lookup
*
* Search in the EFI memory map for the region covering @phys_addr.
* Returns the EFI memory type if the region was found in the memory
* map, EFI_RESERVED_TYPE (zero) otherwise.
*/
int efi_mem_type(unsigned long phys_addr)
{
const efi_memory_desc_t *md;
if (!efi_enabled(EFI_MEMMAP))
return -ENOTSUPP;
for_each_efi_memory_desc(md) {
if ((md->phys_addr <= phys_addr) &&
(phys_addr < (md->phys_addr +
(md->num_pages << EFI_PAGE_SHIFT))))
return md->type;
}
return -EINVAL;
}
#endif
int efi_status_to_err(efi_status_t status)
{
int err;
switch (status) {
case EFI_SUCCESS:
err = 0;
break;
case EFI_INVALID_PARAMETER:
err = -EINVAL;
break;
case EFI_OUT_OF_RESOURCES:
err = -ENOSPC;
break;
case EFI_DEVICE_ERROR:
err = -EIO;
break;
case EFI_WRITE_PROTECTED:
err = -EROFS;
break;
case EFI_SECURITY_VIOLATION:
err = -EACCES;
break;
case EFI_NOT_FOUND:
err = -ENOENT;
break;
case EFI_ABORTED:
err = -EINTR;
break;
default:
err = -EINVAL;
}
return err;
}
static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init;
static int __init efi_memreserve_map_root(void)
{
if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR)
return -ENODEV;
efi_memreserve_root = memremap(efi.mem_reserve,
sizeof(*efi_memreserve_root),
MEMREMAP_WB);
if (WARN_ON_ONCE(!efi_memreserve_root))
return -ENOMEM;
return 0;
}
int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size)
{
struct linux_efi_memreserve *rsv;
unsigned long prsv;
int rc, index;
if (efi_memreserve_root == (void *)ULONG_MAX)
return -ENODEV;
if (!efi_memreserve_root) {
rc = efi_memreserve_map_root();
if (rc)
return rc;
}
/* first try to find a slot in an existing linked list entry */
for (prsv = efi_memreserve_root->next; prsv; prsv = rsv->next) {
rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
index = atomic_fetch_add_unless(&rsv->count, 1, rsv->size);
if (index < rsv->size) {
rsv->entry[index].base = addr;
rsv->entry[index].size = size;
memunmap(rsv);
return 0;
}
memunmap(rsv);
}
/* no slot found - allocate a new linked list entry */
rsv = (struct linux_efi_memreserve *)__get_free_page(GFP_ATOMIC);
if (!rsv)
return -ENOMEM;
/*
* The memremap() call above assumes that a linux_efi_memreserve entry
* never crosses a page boundary, so let's ensure that this remains true
* even when kexec'ing a 4k pages kernel from a >4k pages kernel, by
* using SZ_4K explicitly in the size calculation below.
*/
rsv->size = EFI_MEMRESERVE_COUNT(SZ_4K);
atomic_set(&rsv->count, 1);
rsv->entry[0].base = addr;
rsv->entry[0].size = size;
spin_lock(&efi_mem_reserve_persistent_lock);
rsv->next = efi_memreserve_root->next;
efi_memreserve_root->next = __pa(rsv);
spin_unlock(&efi_mem_reserve_persistent_lock);
return 0;
}
static int __init efi_memreserve_root_init(void)
{
if (efi_memreserve_root)
return 0;
if (efi_memreserve_map_root())
efi_memreserve_root = (void *)ULONG_MAX;
return 0;
}
early_initcall(efi_memreserve_root_init);
#ifdef CONFIG_KEXEC
static int update_efi_random_seed(struct notifier_block *nb,
unsigned long code, void *unused)
{
struct linux_efi_random_seed *seed;
u32 size = 0;
if (!kexec_in_progress)
return NOTIFY_DONE;
seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
if (seed != NULL) {
size = min(seed->size, EFI_RANDOM_SEED_SIZE);
memunmap(seed);
} else {
pr_err("Could not map UEFI random seed!\n");
}
if (size > 0) {
seed = memremap(efi.rng_seed, sizeof(*seed) + size,
MEMREMAP_WB);
if (seed != NULL) {
seed->size = size;
get_random_bytes(seed->bits, seed->size);
memunmap(seed);
} else {
pr_err("Could not map UEFI random seed!\n");
}
}
return NOTIFY_DONE;
}
static struct notifier_block efi_random_seed_nb = {
.notifier_call = update_efi_random_seed,
};
static int register_update_efi_random_seed(void)
{
if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
return 0;
return register_reboot_notifier(&efi_random_seed_nb);
}
late_initcall(register_update_efi_random_seed);
#endif