efi: move utf16 string functions to efi.h

There are currently two implementations of the utf16 string functions.
Somewhat confusingly, they've got different names.

Centralise the functions in efi.h.

Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: Mike Waychison <mikew@google.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

1 files changed, 4 insertions, 15 deletions

diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c
index 91ddf0f7a1b9..c409a7577afc 100644
--- a/drivers/firmware/google/gsmi.c
+++ b/drivers/firmware/google/gsmi.c
@@ -288,17 +288,6 @@ static int gsmi_exec(u8 func, u8 sub)
         return rc;
 }
 
-/* Return the number of unicode characters in data */
-static size_t
-utf16_strlen(efi_char16_t *data, unsigned long maxlength)
-{
-        unsigned long length = 0;
-
-        while (*data++ != 0 && length < maxlength)
-                length++;
-        return length;
-}
-
 static efi_status_t gsmi_get_variable(efi_char16_t *name,
                                       efi_guid_t *vendor, u32 *attr,
                                       unsigned long *data_size,
@@ -311,7 +300,7 @@ static efi_status_t gsmi_get_variable(efi_char16_t *name,
         };
         efi_status_t ret = EFI_SUCCESS;
         unsigned long flags;
-        size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2);
+        size_t name_len = utf16_strnlen(name, GSMI_BUF_SIZE / 2);
         int rc;
 
         if (name_len >= GSMI_BUF_SIZE / 2)
@@ -380,7 +369,7 @@ static efi_status_t gsmi_get_next_variable(unsigned long *name_size,
                 return EFI_BAD_BUFFER_SIZE;
 
         /* Let's make sure the thing is at least null-terminated */
-        if (utf16_strlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2)
+        if (utf16_strnlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2)
                 return EFI_INVALID_PARAMETER;
 
         spin_lock_irqsave(&gsmi_dev.lock, flags);
@@ -408,7 +397,7 @@ static efi_status_t gsmi_get_next_variable(unsigned long *name_size,
 
                 /* Copy the name back */
                 memcpy(name, gsmi_dev.name_buf->start, GSMI_BUF_SIZE);
-                *name_size = utf16_strlen(name, GSMI_BUF_SIZE / 2) * 2;
+                *name_size = utf16_strnlen(name, GSMI_BUF_SIZE / 2) * 2;
 
                 /* copy guid to return buffer */
                 memcpy(vendor, &param.guid, sizeof(param.guid));
@@ -434,7 +423,7 @@ static efi_status_t gsmi_set_variable(efi_char16_t *name,
                               EFI_VARIABLE_BOOTSERVICE_ACCESS |
                               EFI_VARIABLE_RUNTIME_ACCESS,
         };
-        size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2);
+        size_t name_len = utf16_strnlen(name, GSMI_BUF_SIZE / 2);
         efi_status_t ret = EFI_SUCCESS;
         int rc;
         unsigned long flags;