summaryrefslogtreecommitdiffstats
path: root/drivers/firmware/efi/libstub/intrinsics.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/firmware/efi/libstub/intrinsics.c')
-rw-r--r--drivers/firmware/efi/libstub/intrinsics.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/intrinsics.c b/drivers/firmware/efi/libstub/intrinsics.c
index 965e734f6f98..418cd2e6dccc 100644
--- a/drivers/firmware/efi/libstub/intrinsics.c
+++ b/drivers/firmware/efi/libstub/intrinsics.c
@@ -15,8 +15,31 @@ void *__memmove(void *__dest, const void *__src, size_t count) __alias(memmove);
void *__memset(void *s, int c, size_t count) __alias(memset);
#endif
+static void *efistub_memmove(u8 *dst, const u8 *src, size_t len)
+{
+ if (src > dst || dst >= (src + len))
+ for (size_t i = 0; i < len; i++)
+ dst[i] = src[i];
+ else
+ for (ssize_t i = len - 1; i >= 0; i--)
+ dst[i] = src[i];
+
+ return dst;
+}
+
+static void *efistub_memset(void *dst, int c, size_t len)
+{
+ for (u8 *d = dst; len--; d++)
+ *d = c;
+
+ return dst;
+}
+
void *memcpy(void *dst, const void *src, size_t len)
{
+ if (efi_table_attr(efi_system_table, boottime) == NULL)
+ return efistub_memmove(dst, src, len);
+
efi_bs_call(copy_mem, dst, src, len);
return dst;
}
@@ -25,6 +48,9 @@ extern void *memmove(void *dst, const void *src, size_t len) __alias(memcpy);
void *memset(void *dst, int c, size_t len)
{
+ if (efi_table_attr(efi_system_table, boottime) == NULL)
+ return efistub_memset(dst, c, len);
+
efi_bs_call(set_mem, dst, len, c & U8_MAX);
return dst;
}