Commit db93f8b4 authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Three groups of fixes:

   1. Make sure we don't execute the early microcode patching if family
      < 6, since it would touch MSRs which don't exist on those
      families, causing crashes.

   2. The Xen partial emulation of HyperV can be dealt with more
      gracefully than just disabling the driver.

   3. More EFI variable space magic.  In particular, variables hidden
      from runtime code need to be taken into account too."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode: Verify the family before dispatching microcode patching
  x86, hyperv: Handle Xen emulation of Hyper-V more gracefully
  x86,efi: Implement efi_no_storage_paranoia parameter
  efi: Export efi_query_variable_store() for efivars.ko
  x86/Kconfig: Make EFI select UCS2_STRING
  efi: Distinguish between "remaining space" and actually used space
  efi: Pass boot services variable info to runtime code
  Move utf16 functions to kernel core and rename
  x86,efi: Check max_size only if it is non-zero.
  x86, efivars: firmware bug workarounds should be in platform code
parents 8c3a13c8 c0a9f451
......@@ -788,6 +788,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
efi_no_storage_paranoia [EFI; X86]
Using this parameter you can use more than 50% of
your efi variable storage. Use this parameter only if
you are really sure that your UEFI does sane gc and
fulfills the spec otherwise your board may brick.
eisa_irq_edge= [PARISC,HW]
See header of drivers/parisc/eisa.c.
......
......@@ -1549,6 +1549,7 @@ config X86_SMAP
config EFI
bool "EFI runtime service support"
depends on ACPI
select UCS2_STRING
---help---
This enables the kernel to use EFI runtime services that are
available (such as the EFI variable services).
......
......@@ -251,6 +251,51 @@ static void find_bits(unsigned long mask, u8 *pos, u8 *size)
*size = len;
}
static efi_status_t setup_efi_vars(struct boot_params *params)
{
struct setup_data *data;
struct efi_var_bootdata *efidata;
u64 store_size, remaining_size, var_size;
efi_status_t status;
if (!sys_table->runtime->query_variable_info)
return EFI_UNSUPPORTED;
data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
while (data && data->next)
data = (struct setup_data *)(unsigned long)data->next;
status = efi_call_phys4(sys_table->runtime->query_variable_info,
EFI_VARIABLE_NON_VOLATILE |
EFI_VARIABLE_BOOTSERVICE_ACCESS |
EFI_VARIABLE_RUNTIME_ACCESS, &store_size,
&remaining_size, &var_size);
if (status != EFI_SUCCESS)
return status;
status = efi_call_phys3(sys_table->boottime->allocate_pool,
EFI_LOADER_DATA, sizeof(*efidata), &efidata);
if (status != EFI_SUCCESS)
return status;
efidata->data.type = SETUP_EFI_VARS;
efidata->data.len = sizeof(struct efi_var_bootdata) -
sizeof(struct setup_data);
efidata->data.next = 0;
efidata->store_size = store_size;
efidata->remaining_size = remaining_size;
efidata->max_var_size = var_size;
if (data)
data->next = (unsigned long)efidata;
else
params->hdr.setup_data = (unsigned long)efidata;
}
static efi_status_t setup_efi_pci(struct boot_params *params)
{
efi_pci_io_protocol *pci;
......@@ -1157,6 +1202,8 @@ struct boot_params *efi_main(void *handle, efi_system_table_t *_table,
setup_graphics(boot_params);
setup_efi_vars(boot_params);
setup_efi_pci(boot_params);
status = efi_call_phys3(sys_table->boottime->allocate_pool,
......
......@@ -102,6 +102,13 @@ extern void efi_call_phys_epilog(void);
extern void efi_unmap_memmap(void);
extern void efi_memory_uc(u64 addr, unsigned long size);
struct efi_var_bootdata {
struct setup_data data;
u64 store_size;
u64 remaining_size;
u64 max_var_size;
};
#ifdef CONFIG_EFI
static inline bool efi_is_native(void)
......
......@@ -6,6 +6,7 @@
#define SETUP_E820_EXT 1
#define SETUP_DTB 2
#define SETUP_PCI 3
#define SETUP_EFI_VARS 4
/* ram_size flags */
#define RAMDISK_IMAGE_START_MASK 0x07FF
......
......@@ -35,13 +35,6 @@ static bool __init ms_hyperv_platform(void)
if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
return false;
/*
* Xen emulates Hyper-V to support enlightened Windows.
* Check to see first if we are on a Xen Hypervisor.
*/
if (xen_cpuid_base())
return false;
cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS,
&eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]);
......@@ -82,12 +75,6 @@ static void __init ms_hyperv_init_platform(void)
if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE)
clocksource_register_hz(&hyperv_cs, NSEC_PER_SEC/100);
#if IS_ENABLED(CONFIG_HYPERV)
/*
* Setup the IDT for hypervisor callback.
*/
alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, hyperv_callback_vector);
#endif
}
const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = {
......@@ -103,6 +90,11 @@ static irq_handler_t vmbus_isr;
void hv_register_vmbus_handler(int irq, irq_handler_t handler)
{
/*
* Setup the IDT for hypervisor callback.
*/
alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, hyperv_callback_vector);
vmbus_irq = irq;
vmbus_isr = handler;
}
......
......@@ -45,9 +45,6 @@ static int __cpuinit x86_vendor(void)
u32 eax = 0x00000000;
u32 ebx, ecx = 0, edx;
if (!have_cpuid_p())
return X86_VENDOR_UNKNOWN;
native_cpuid(&eax, &ebx, &ecx, &edx);
if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
......@@ -59,18 +56,45 @@ static int __cpuinit x86_vendor(void)
return X86_VENDOR_UNKNOWN;
}
static int __cpuinit x86_family(void)
{
u32 eax = 0x00000001;
u32 ebx, ecx = 0, edx;
int x86;
native_cpuid(&eax, &ebx, &ecx, &edx);
x86 = (eax >> 8) & 0xf;
if (x86 == 15)
x86 += (eax >> 20) & 0xff;
return x86;
}
void __init load_ucode_bsp(void)
{
int vendor = x86_vendor();
int vendor, x86;
if (!have_cpuid_p())
return;
if (vendor == X86_VENDOR_INTEL)
vendor = x86_vendor();
x86 = x86_family();
if (vendor == X86_VENDOR_INTEL && x86 >= 6)
load_ucode_intel_bsp();
}
void __cpuinit load_ucode_ap(void)
{
int vendor = x86_vendor();
int vendor, x86;
if (!have_cpuid_p())
return;
vendor = x86_vendor();
x86 = x86_family();
if (vendor == X86_VENDOR_INTEL)
if (vendor == X86_VENDOR_INTEL && x86 >= 6)
load_ucode_intel_ap();
}
......@@ -41,6 +41,7 @@
#include <linux/io.h>
#include <linux/reboot.h>
#include <linux/bcd.h>
#include <linux/ucs2_string.h>
#include <asm/setup.h>
#include <asm/efi.h>
......@@ -51,6 +52,13 @@
#define EFI_DEBUG 1
/*
* There's some additional metadata associated with each
* variable. Intel's reference implementation is 60 bytes - bump that
* to account for potential alignment constraints
*/
#define VAR_METADATA_SIZE 64
struct efi __read_mostly efi = {
.mps = EFI_INVALID_TABLE_ADDR,
.acpi = EFI_INVALID_TABLE_ADDR,
......@@ -69,6 +77,13 @@ struct efi_memory_map memmap;
static struct efi efi_phys __initdata;
static efi_system_table_t efi_systab __initdata;
static u64 efi_var_store_size;
static u64 efi_var_remaining_size;
static u64 efi_var_max_var_size;
static u64 boot_used_size;
static u64 boot_var_size;
static u64 active_size;
unsigned long x86_efi_facility;
/*
......@@ -98,6 +113,15 @@ static int __init setup_add_efi_memmap(char *arg)
}
early_param("add_efi_memmap", setup_add_efi_memmap);
static bool efi_no_storage_paranoia;
static int __init setup_storage_paranoia(char *arg)
{
efi_no_storage_paranoia = true;
return 0;
}
early_param("efi_no_storage_paranoia", setup_storage_paranoia);
static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
{
......@@ -162,8 +186,53 @@ static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
efi_char16_t *name,
efi_guid_t *vendor)
{
return efi_call_virt3(get_next_variable,
name_size, name, vendor);
efi_status_t status;
static bool finished = false;
static u64 var_size;
status = efi_call_virt3(get_next_variable,
name_size, name, vendor);
if (status == EFI_NOT_FOUND) {
finished = true;
if (var_size < boot_used_size) {
boot_var_size = boot_used_size - var_size;
active_size += boot_var_size;
} else {
printk(KERN_WARNING FW_BUG "efi: Inconsistent initial sizes\n");
}
}
if (boot_used_size && !finished) {
unsigned long size;
u32 attr;
efi_status_t s;
void *tmp;
s = virt_efi_get_variable(name, vendor, &attr, &size, NULL);
if (s != EFI_BUFFER_TOO_SMALL || !size)
return status;
tmp = kmalloc(size, GFP_ATOMIC);
if (!tmp)
return status;
s = virt_efi_get_variable(name, vendor, &attr, &size, tmp);
if (s == EFI_SUCCESS && (attr & EFI_VARIABLE_NON_VOLATILE)) {
var_size += size;
var_size += ucs2_strsize(name, 1024);
active_size += size;
active_size += VAR_METADATA_SIZE;
active_size += ucs2_strsize(name, 1024);
}
kfree(tmp);
}
return status;
}
static efi_status_t virt_efi_set_variable(efi_char16_t *name,
......@@ -172,9 +241,34 @@ static efi_status_t virt_efi_set_variable(efi_char16_t *name,
unsigned long data_size,
void *data)
{
return efi_call_virt5(set_variable,
name, vendor, attr,
data_size, data);
efi_status_t status;
u32 orig_attr = 0;
unsigned long orig_size = 0;
status = virt_efi_get_variable(name, vendor, &orig_attr, &orig_size,
NULL);
if (status != EFI_BUFFER_TOO_SMALL)
orig_size = 0;
status = efi_call_virt5(set_variable,
name, vendor, attr,
data_size, data);
if (status == EFI_SUCCESS) {
if (orig_size) {
active_size -= orig_size;
active_size -= ucs2_strsize(name, 1024);
active_size -= VAR_METADATA_SIZE;
}
if (data_size) {
active_size += data_size;
active_size += ucs2_strsize(name, 1024);
active_size += VAR_METADATA_SIZE;
}
}
return status;
}
static efi_status_t virt_efi_query_variable_info(u32 attr,
......@@ -682,6 +776,9 @@ void __init efi_init(void)
char vendor[100] = "unknown";
int i = 0;
void *tmp;
struct setup_data *data;
struct efi_var_bootdata *efi_var_data;
u64 pa_data;
#ifdef CONFIG_X86_32
if (boot_params.efi_info.efi_systab_hi ||
......@@ -699,6 +796,22 @@ void __init efi_init(void)
if (efi_systab_init(efi_phys.systab))
return;
pa_data = boot_params.hdr.setup_data;
while (pa_data) {
data = early_ioremap(pa_data, sizeof(*efi_var_data));
if (data->type == SETUP_EFI_VARS) {
efi_var_data = (struct efi_var_bootdata *)data;
efi_var_store_size = efi_var_data->store_size;
efi_var_remaining_size = efi_var_data->remaining_size;
efi_var_max_var_size = efi_var_data->max_var_size;
}
pa_data = data->next;
early_iounmap(data, sizeof(*efi_var_data));
}
boot_used_size = efi_var_store_size - efi_var_remaining_size;
set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
/*
......@@ -999,3 +1112,48 @@ u64 efi_mem_attributes(unsigned long phys_addr)
}
return 0;
}
/*
* Some firmware has serious problems when using more than 50% of the EFI
* variable store, i.e. it triggers bugs that can brick machines. Ensure that
* we never use more than this safe limit.
*
* Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
* store.
*/
efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
{
efi_status_t status;
u64 storage_size, remaining_size, max_size;
status = efi.query_variable_info(attributes, &storage_size,
&remaining_size, &max_size);
if (status != EFI_SUCCESS)
return status;
if (!max_size && remaining_size > size)
printk_once(KERN_ERR FW_BUG "Broken EFI implementation"
" is returning MaxVariableSize=0\n");
/*
* Some firmware implementations refuse to boot if there's insufficient
* space in the variable store. We account for that by refusing the
* write if permitting it would reduce the available space to under
* 50%. However, some firmware won't reclaim variable space until
* after the used (not merely the actively used) space drops below
* a threshold. We can approximate that case with the value calculated
* above. If both the firmware and our calculations indicate that the
* available space would drop below 50%, refuse the write.
*/
if (!storage_size || size > remaining_size ||
(max_size && size > max_size))
return EFI_OUT_OF_RESOURCES;
if (!efi_no_storage_paranoia &&
((active_size + size + VAR_METADATA_SIZE > storage_size / 2) &&
(remaining_size - size < storage_size / 2)))
return EFI_OUT_OF_RESOURCES;
return EFI_SUCCESS;
}
EXPORT_SYMBOL_GPL(efi_query_variable_store);
......@@ -39,6 +39,7 @@ config FIRMWARE_MEMMAP
config EFI_VARS
tristate "EFI Variable Support via sysfs"
depends on EFI
select UCS2_STRING
default n
help
If you say Y here, you are able to get EFI (Extensible Firmware
......
......@@ -80,6 +80,7 @@
#include <linux/slab.h>
#include <linux/pstore.h>
#include <linux/ctype.h>
#include <linux/ucs2_string.h>
#include <linux/fs.h>
#include <linux/ramfs.h>
......@@ -172,51 +173,6 @@ static void efivar_update_sysfs_entries(struct work_struct *);
static DECLARE_WORK(efivar_work, efivar_update_sysfs_entries);
static bool efivar_wq_enabled = true;
/* Return the number of unicode characters in data */
static unsigned long
utf16_strnlen(efi_char16_t *s, size_t maxlength)
{
unsigned long length = 0;
while (*s++ != 0 && length < maxlength)
length++;
return length;
}
static inline unsigned long
utf16_strlen(efi_char16_t *s)
{
return utf16_strnlen(s, ~0UL);
}
/*
* Return the number of bytes is the length of this string
* Note: this is NOT the same as the number of unicode characters
*/
static inline unsigned long
utf16_strsize(efi_char16_t *data, unsigned long maxlength)
{
return utf16_strnlen(data, maxlength/sizeof(efi_char16_t)) * sizeof(efi_char16_t);
}
static inline int
utf16_strncmp(const efi_char16_t *a, const efi_char16_t *b, size_t len)
{
while (1) {
if (len == 0)
return 0;
if (*a < *b)
return -1;
if (*a > *b)
return 1;
if (*a == 0) /* implies *b == 0 */
return 0;
a++;
b++;
len--;
}
}
static bool
validate_device_path(struct efi_variable *var, int match, u8 *buffer,
unsigned long len)
......@@ -268,7 +224,7 @@ validate_load_option(struct efi_variable *var, int match, u8 *buffer,
u16 filepathlength;
int i, desclength = 0, namelen;
namelen = utf16_strnlen(var->VariableName, sizeof(var->VariableName));
namelen = ucs2_strnlen(var->VariableName, sizeof(var->VariableName));
/* Either "Boot" or "Driver" followed by four digits of hex */
for (i = match; i < match+4; i++) {
......@@ -291,7 +247,7 @@ validate_load_option(struct efi_variable *var, int match, u8 *buffer,
* There's no stored length for the description, so it has to be
* found by hand
*/
desclength = utf16_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2;
desclength = ucs2_strsize((efi_char16_t *)(buffer + 6), len - 6) + 2;
/* Each boot entry must have a descriptor */
if (!desclength)
......@@ -436,24 +392,12 @@ static efi_status_t
check_var_size_locked(struct efivars *efivars, u32 attributes,
unsigned long size)
{
u64 storage_size, remaining_size, max_size;
efi_status_t status;
const struct efivar_operations *fops = efivars->ops;
if (!efivars->ops->query_variable_info)
if (!efivars->ops->query_variable_store)
return EFI_UNSUPPORTED;
status = fops->query_variable_info(attributes, &storage_size,
&remaining_size, &max_size);
if (status != EFI_SUCCESS)
return status;
if (!storage_size || size > remaining_size || size > max_size ||
(remaining_size - size) < (storage_size / 2))
return EFI_OUT_OF_RESOURCES;
return status;
return fops->query_variable_store(attributes, size);
}
......@@ -593,7 +537,7 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
spin_lock_irq(&efivars->lock);
status = check_var_size_locked(efivars, new_var->Attributes,
new_var->DataSize + utf16_strsize(new_var->VariableName, 1024));
new_var->DataSize + ucs2_strsize(new_var->VariableName, 1024));
if (status == EFI_SUCCESS || status == EFI_UNSUPPORTED)
status = efivars->ops->set_variable(new_var->VariableName,
......@@ -771,7 +715,7 @@ static ssize_t efivarfs_file_write(struct file *file,
* QueryVariableInfo() isn't supported by the firmware.
*/
varsize = datasize + utf16_strsize(var->var.VariableName, 1024);
varsize = datasize + ucs2_strsize(var->var.VariableName, 1024);
status = check_var_size(efivars, attributes, varsize);
if (status != EFI_SUCCESS) {
......@@ -1223,7 +1167,7 @@ static int efivarfs_fill_super(struct super_block *sb, void *data, int silent)
inode = NULL;
len = utf16_strlen(entry->var.VariableName);
len = ucs2_strlen(entry->var.VariableName);
/* name, plus '-', plus GUID, plus NUL*/
name = kmalloc(len + 1 + GUID_LEN + 1, GFP_ATOMIC);
......@@ -1481,8 +1425,8 @@ static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
if (efi_guidcmp(entry->var.VendorGuid, vendor))
continue;
if (utf16_strncmp(entry->var.VariableName, efi_name,
utf16_strlen(efi_name))) {
if (ucs2_strncmp(entry->var.VariableName, efi_name,
ucs2_strlen(efi_name))) {
/*
* Check if an old format,
* which doesn't support holding
......@@ -1494,8 +1438,8 @@ static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
for (i = 0; i < DUMP_NAME_LEN; i++)
efi_name_old[i] = name_old[i];
if (utf16_strncmp(entry->var.VariableName, efi_name_old,
utf16_strlen(efi_name_old)))
if (ucs2_strncmp(entry->var.VariableName, efi_name_old,
ucs2_strlen(efi_name_old)))
continue;
}
......@@ -1573,8 +1517,8 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
* Does this variable already exist?
*/
list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024);
strsize2 = utf16_strsize(new_var->VariableName, 1024);
strsize1 = ucs2_strsize(search_efivar->var.VariableName, 1024);
strsize2 = ucs2_strsize(new_var->VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(&(search_efivar->var.VariableName),
new_var->VariableName, strsize1) &&
......@@ -1590,7 +1534,7 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
}
status = check_var_size_locked(efivars, new_var->Attributes,
new_var->DataSize + utf16_strsize(new_var->VariableName, 1024));
new_var->DataSize + ucs2_strsize(new_var->VariableName, 1024));
if (status && status != EFI_UNSUPPORTED) {
spin_unlock_irq(&efivars->lock);
......@@ -1614,7 +1558,7 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
/* Create the entry in sysfs. Locking is not required here */
status = efivar_create_sysfs_entry(efivars,
utf16_strsize(new_var->VariableName,
ucs2_strsize(new_var->VariableName,
1024),
new_var->VariableName,
&new_var->VendorGuid);
......@@ -1644,8 +1588,8 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
* Does this variable already exist?
*/
list_for_each_entry_safe(search_efivar, n, &efivars->list, list) {
strsize1 = utf16_strsize(search_efivar->var.VariableName, 1024);
strsize2 = utf16_strsize(del_var->VariableName, 1024);
strsize1 = ucs2_strsize(search_efivar->var.VariableName, 1024);
strsize2 = ucs2_strsize(del_var->VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(&(search_efivar->var.VariableName),
del_var->VariableName, strsize1) &&
......@@ -1691,9 +1635,9 @@ static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor)
unsigned long strsize1, strsize2;
bool found = false;
strsize1 = utf16_strsize(variable_name, 1024);
strsize1 = ucs2_strsize(variable_name, 1024);
list_for_each_entry_safe(entry, n, &efivars->list, list) {
strsize2 = utf16_strsize(entry->var.VariableName, 1024);
strsize2 = ucs2_strsize(entry->var.VariableName, 1024);
if (strsize1 == strsize2 &&
!memcmp(variable_name, &(entry->var.VariableName),
strsize2) &&
......@@ -2131,7 +2075,7 @@ efivars_init(void)
ops.get_variable = efi.get_variable;
ops.set_variable = efi.set_variable;
ops.get_next_variable = efi.get_next_variable;
ops.query_variable_info = efi.query_variable_info;
ops.query_variable_store = efi_query_variable_store;
error = register_efivars(&__efivars, &ops, efi_kobj);
if (error)
......
......@@ -333,6 +333,7 @@ typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
unsigned long count,
u64 *max_size,
int *reset_type);
typedef efi_status_t efi_query_variable_store_t(u32 attributes, unsigned long size);
/*
* EFI Configuration Table and GUID definitions
......@@ -575,9 +576,15 @@ extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if pos
#ifdef CONFIG_X86
extern void efi_late_init(void);
extern void efi_free_boot_services(void);
extern efi_status_t efi_query_variable_store(u32 attributes, unsigned long size);
#else
static inline void efi_late_init(void) {}
static inline void efi_free_boot_services(void) {}
static inline efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
{
return EFI_SUCCESS;
}
#endif
extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr);
extern u64 efi_get_iobase (void);
......@@ -731,7 +738,7 @@ struct efivar_operations {
efi_get_variable_t *get_variable;
efi_get_next_variable_t *get_next_variable;
efi_set_variable_t *set_variable;
efi_query_variable_info_t *query_variable_info;
efi_query_variable_store_t *query_variable_store;
};
struct efivars {
......
#ifndef _LINUX_UCS2_STRING_H_
#define _LINUX_UCS2_STRING_H_
#include <linux/types.h> /* for size_t */
#include <linux/stddef.h> /* for NULL */
typedef u16 ucs2_char_t;
unsigned long ucs2_strnlen(const ucs2_char_t *s, size_t maxlength);
unsigned long ucs2_strlen(const ucs2_char_t *s);
unsigned long ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength);
int ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len);
#endif /* _LINUX_UCS2_STRING_H_ */
......@@ -404,4 +404,7 @@ config OID_REGISTRY
help
Enable fast lookup object identifier registry.
config UCS2_STRING
tristate
endmenu
......@@ -174,3 +174,5 @@ quiet_cmd_build_OID_registry = GEN $@
cmd_build_OID_registry = perl $(srctree)/$(src)/build_OID_registry $< $@
clean-files += oid_registry_data.c
obj-$(CONFIG_UCS2_STRING) += ucs2_string.o
#include <linux/ucs2_string.h>
#include <linux/module.h>
/* Return the number of unicode characters in data */
unsigned long
ucs2_strnlen(const ucs2_char_t *s, size_t maxlength)
{
unsigned long length = 0;
while (*s++ != 0 && length < maxlength)
length++;
return length;
}
EXPORT_SYMBOL(ucs2_strnlen);
unsigned long
ucs2_strlen(const ucs2_char_t *s)
{
return ucs2_strnlen(s, ~0UL);
}
EXPORT_SYMBOL(ucs2_strlen);
/*
* Return the number of bytes is the length of this string
* Note: this is NOT the same as the number of unicode characters
*/
unsigned long
ucs2_strsize(const ucs2_char_t *data, unsigned long maxlength)
{
return ucs2_strnlen(data, maxlength/sizeof(ucs2_char_t)) * sizeof(ucs2_char_t);
}
EXPORT_SYMBOL(ucs2_strsize);
int
ucs2_strncmp(const ucs2_char_t *a, const ucs2_char_t *b, size_t len)
{
while (1) {
if (len == 0)
return 0;
if (*a < *b)
return -1;
if (*a > *b)
return 1;
if (*a == 0) /* implies *b == 0 */
return 0;
a++;
b++;
len--;
}
}
EXPORT_SYMBOL(ucs2_strncmp);
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