diff options
author | H. Peter Anvin <hpa@linux.intel.com> | 2013-04-19 17:09:03 -0700 |
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committer | H. Peter Anvin <hpa@linux.intel.com> | 2013-04-19 17:09:03 -0700 |
commit | c0a9f451e4e7ecd2ad1a6c27ea5c31d0226bdddf (patch) | |
tree | dcb22c46c33a994db115ec8925093f91f6463f15 | |
parent | 74c3e3fcf350b2e7e3eaf9550528ee3f74e44b37 (diff) | |
parent | 8c58bf3eec3b8fc8162fe557e9361891c20758f2 (diff) | |
download | op-kernel-dev-c0a9f451e4e7ecd2ad1a6c27ea5c31d0226bdddf.zip op-kernel-dev-c0a9f451e4e7ecd2ad1a6c27ea5c31d0226bdddf.tar.gz |
Merge remote-tracking branch 'efi/urgent' into x86/urgent
Matt Fleming (1):
x86, efivars: firmware bug workarounds should be in platform
code
Matthew Garrett (3):
Move utf16 functions to kernel core and rename
efi: Pass boot services variable info to runtime code
efi: Distinguish between "remaining space" and actually used
space
Richard Weinberger (2):
x86,efi: Check max_size only if it is non-zero.
x86,efi: Implement efi_no_storage_paranoia parameter
Sergey Vlasov (2):
x86/Kconfig: Make EFI select UCS2_STRING
efi: Export efi_query_variable_store() for efivars.ko
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
-rw-r--r-- | Documentation/kernel-parameters.txt | 6 | ||||
-rw-r--r-- | arch/x86/Kconfig | 1 | ||||
-rw-r--r-- | arch/x86/boot/compressed/eboot.c | 47 | ||||
-rw-r--r-- | arch/x86/include/asm/efi.h | 7 | ||||
-rw-r--r-- | arch/x86/include/uapi/asm/bootparam.h | 1 | ||||
-rw-r--r-- | arch/x86/platform/efi/efi.c | 168 | ||||
-rw-r--r-- | drivers/firmware/Kconfig | 1 | ||||
-rw-r--r-- | drivers/firmware/efivars.c | 98 | ||||
-rw-r--r-- | include/linux/efi.h | 9 | ||||
-rw-r--r-- | include/linux/ucs2_string.h | 14 | ||||
-rw-r--r-- | lib/Kconfig | 3 | ||||
-rw-r--r-- | lib/Makefile | 2 | ||||
-rw-r--r-- | lib/ucs2_string.c | 51 |
13 files changed, 325 insertions, 83 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4609e81..d1cc3a9 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -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. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 70c0f3d..15b5cef 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -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). diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index c205035..8615f75 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -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, diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index 60c89f3..2fb5d58 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -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) diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h index c15ddaf..0874424 100644 --- a/arch/x86/include/uapi/asm/bootparam.h +++ b/arch/x86/include/uapi/asm/bootparam.h @@ -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 diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 5f2ecaf..e4a86a6 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -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); diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index 42c759a..3e53200 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -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 diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index 7acafb8..182ce94 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -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) diff --git a/include/linux/efi.h b/include/linux/efi.h index 9bf2f1f..3d7df3d 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -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 { diff --git a/include/linux/ucs2_string.h b/include/linux/ucs2_string.h new file mode 100644 index 0000000..cbb20af --- /dev/null +++ b/include/linux/ucs2_string.h @@ -0,0 +1,14 @@ +#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_ */ diff --git a/lib/Kconfig b/lib/Kconfig index 3958dc4..fe01d41 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -404,4 +404,7 @@ config OID_REGISTRY help Enable fast lookup object identifier registry. +config UCS2_STRING + tristate + endmenu diff --git a/lib/Makefile b/lib/Makefile index d7946ff..6e2cc56 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -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 diff --git a/lib/ucs2_string.c b/lib/ucs2_string.c new file mode 100644 index 0000000..6f500ef --- /dev/null +++ b/lib/ucs2_string.c @@ -0,0 +1,51 @@ +#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); |