We will be using the libstub static library also to build the EFI zboot
decompressor, which is a separate binary and does not carry all the
dependencies of efi-stub-helper.c, which is where efi_printk() currently
lives.
So split it off into printk.c so we can incorporate it separately.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
drivers/firmware/efi/libstub/Makefile | 2 +-
drivers/firmware/efi/libstub/efi-stub-helper.c | 141 -----------------
drivers/firmware/efi/libstub/printk.c | 158 ++++++++++++++++++++
3 files changed, 159 insertions(+), 142 deletions(-)
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index d0537573501e..475224be08e1 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -55,7 +55,7 @@ KCOV_INSTRUMENT := n
lib-y := efi-stub-helper.o gop.o secureboot.o tpm.o \
file.o mem.o random.o randomalloc.o pci.o \
skip_spaces.o lib-cmdline.o lib-ctype.o \
- alignedmem.o relocate.o vsprintf.o
+ alignedmem.o relocate.o vsprintf.o printk.o
# include the stub's generic dependencies from lib/ when building for ARM/arm64
efi-deps-y := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 3d972061c1b0..45910c834133 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -20,7 +20,6 @@
bool efi_nochunk;
bool efi_nokaslr = !IS_ENABLED(CONFIG_RANDOMIZE_BASE);
-int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
bool efi_novamap;
static bool efi_noinitrd;
@@ -32,146 +31,6 @@ bool __pure __efi_soft_reserve_enabled(void)
return !efi_nosoftreserve;
}
-/**
- * efi_char16_puts() - Write a UCS-2 encoded string to the console
- * @str: UCS-2 encoded string
- */
-void efi_char16_puts(efi_char16_t *str)
-{
- efi_call_proto(efi_table_attr(efi_system_table, con_out),
- output_string, str);
-}
-
-static
-u32 utf8_to_utf32(const u8 **s8)
-{
- u32 c32;
- u8 c0, cx;
- size_t clen, i;
-
- c0 = cx = *(*s8)++;
- /*
- * The position of the most-significant 0 bit gives us the length of
- * a multi-octet encoding.
- */
- for (clen = 0; cx & 0x80; ++clen)
- cx <<= 1;
- /*
- * If the 0 bit is in position 8, this is a valid single-octet
- * encoding. If the 0 bit is in position 7 or positions 1-3, the
- * encoding is invalid.
- * In either case, we just return the first octet.
- */
- if (clen < 2 || clen > 4)
- return c0;
- /* Get the bits from the first octet. */
- c32 = cx >> clen--;
- for (i = 0; i < clen; ++i) {
- /* Trailing octets must have 10 in most significant bits. */
- cx = (*s8)[i] ^ 0x80;
- if (cx & 0xc0)
- return c0;
- c32 = (c32 << 6) | cx;
- }
- /*
- * Check for validity:
- * - The character must be in the Unicode range.
- * - It must not be a surrogate.
- * - It must be encoded using the correct number of octets.
- */
- if (c32 > 0x10ffff ||
- (c32 & 0xf800) == 0xd800 ||
- clen != (c32 >= 0x80) + (c32 >= 0x800) + (c32 >= 0x10000))
- return c0;
- *s8 += clen;
- return c32;
-}
-
-/**
- * efi_puts() - Write a UTF-8 encoded string to the console
- * @str: UTF-8 encoded string
- */
-void efi_puts(const char *str)
-{
- efi_char16_t buf[128];
- size_t pos = 0, lim = ARRAY_SIZE(buf);
- const u8 *s8 = (const u8 *)str;
- u32 c32;
-
- while (*s8) {
- if (*s8 == '\n')
- buf[pos++] = L'\r';
- c32 = utf8_to_utf32(&s8);
- if (c32 < 0x10000) {
- /* Characters in plane 0 use a single word. */
- buf[pos++] = c32;
- } else {
- /*
- * Characters in other planes encode into a surrogate
- * pair.
- */
- buf[pos++] = (0xd800 - (0x10000 >> 10)) + (c32 >> 10);
- buf[pos++] = 0xdc00 + (c32 & 0x3ff);
- }
- if (*s8 == '\0' || pos >= lim - 2) {
- buf[pos] = L'\0';
- efi_char16_puts(buf);
- pos = 0;
- }
- }
-}
-
-/**
- * efi_printk() - Print a kernel message
- * @fmt: format string
- *
- * The first letter of the format string is used to determine the logging level
- * of the message. If the level is less then the current EFI logging level, the
- * message is suppressed. The message will be truncated to 255 bytes.
- *
- * Return: number of printed characters
- */
-int efi_printk(const char *fmt, ...)
-{
- char printf_buf[256];
- va_list args;
- int printed;
- int loglevel = printk_get_level(fmt);
-
- switch (loglevel) {
- case '0' ... '9':
- loglevel -= '0';
- break;
- default:
- /*
- * Use loglevel -1 for cases where we just want to print to
- * the screen.
- */
- loglevel = -1;
- break;
- }
-
- if (loglevel >= efi_loglevel)
- return 0;
-
- if (loglevel >= 0)
- efi_puts("EFI stub: ");
-
- fmt = printk_skip_level(fmt);
-
- va_start(args, fmt);
- printed = vsnprintf(printf_buf, sizeof(printf_buf), fmt, args);
- va_end(args);
-
- efi_puts(printf_buf);
- if (printed >= sizeof(printf_buf)) {
- efi_puts("[Message truncated]\n");
- return -1;
- }
-
- return printed;
-}
-
/**
* efi_parse_options() - Parse EFI command line options
* @cmdline: kernel command line
diff --git a/drivers/firmware/efi/libstub/printk.c b/drivers/firmware/efi/libstub/printk.c
new file mode 100644
index 000000000000..ec09bf895c1a
--- /dev/null
+++ b/drivers/firmware/efi/libstub/printk.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ */
+
+#include <linux/ctype.h>
+#include <linux/efi.h>
+#include <linux/kernel.h>
+#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+
+/**
+ * efi_char16_puts() - Write a UCS-2 encoded string to the console
+ * @str: UCS-2 encoded string
+ */
+void efi_char16_puts(efi_char16_t *str)
+{
+ efi_call_proto(efi_table_attr(efi_system_table, con_out),
+ output_string, str);
+}
+
+static
+u32 utf8_to_utf32(const u8 **s8)
+{
+ u32 c32;
+ u8 c0, cx;
+ size_t clen, i;
+
+ c0 = cx = *(*s8)++;
+ /*
+ * The position of the most-significant 0 bit gives us the length of
+ * a multi-octet encoding.
+ */
+ for (clen = 0; cx & 0x80; ++clen)
+ cx <<= 1;
+ /*
+ * If the 0 bit is in position 8, this is a valid single-octet
+ * encoding. If the 0 bit is in position 7 or positions 1-3, the
+ * encoding is invalid.
+ * In either case, we just return the first octet.
+ */
+ if (clen < 2 || clen > 4)
+ return c0;
+ /* Get the bits from the first octet. */
+ c32 = cx >> clen--;
+ for (i = 0; i < clen; ++i) {
+ /* Trailing octets must have 10 in most significant bits. */
+ cx = (*s8)[i] ^ 0x80;
+ if (cx & 0xc0)
+ return c0;
+ c32 = (c32 << 6) | cx;
+ }
+ /*
+ * Check for validity:
+ * - The character must be in the Unicode range.
+ * - It must not be a surrogate.
+ * - It must be encoded using the correct number of octets.
+ */
+ if (c32 > 0x10ffff ||
+ (c32 & 0xf800) == 0xd800 ||
+ clen != (c32 >= 0x80) + (c32 >= 0x800) + (c32 >= 0x10000))
+ return c0;
+ *s8 += clen;
+ return c32;
+}
+
+/**
+ * efi_puts() - Write a UTF-8 encoded string to the console
+ * @str: UTF-8 encoded string
+ */
+void efi_puts(const char *str)
+{
+ efi_char16_t buf[128];
+ size_t pos = 0, lim = ARRAY_SIZE(buf);
+ const u8 *s8 = (const u8 *)str;
+ u32 c32;
+
+ while (*s8) {
+ if (*s8 == '\n')
+ buf[pos++] = L'\r';
+ c32 = utf8_to_utf32(&s8);
+ if (c32 < 0x10000) {
+ /* Characters in plane 0 use a single word. */
+ buf[pos++] = c32;
+ } else {
+ /*
+ * Characters in other planes encode into a surrogate
+ * pair.
+ */
+ buf[pos++] = (0xd800 - (0x10000 >> 10)) + (c32 >> 10);
+ buf[pos++] = 0xdc00 + (c32 & 0x3ff);
+ }
+ if (*s8 == '\0' || pos >= lim - 2) {
+ buf[pos] = L'\0';
+ efi_char16_puts(buf);
+ pos = 0;
+ }
+ }
+}
+
+/**
+ * efi_printk() - Print a kernel message
+ * @fmt: format string
+ *
+ * The first letter of the format string is used to determine the logging level
+ * of the message. If the level is less then the current EFI logging level, the
+ * message is suppressed. The message will be truncated to 255 bytes.
+ *
+ * Return: number of printed characters
+ */
+int efi_printk(const char *fmt, ...)
+{
+ char printf_buf[256];
+ va_list args;
+ int printed;
+ int loglevel = printk_get_level(fmt);
+
+ switch (loglevel) {
+ case '0' ... '9':
+ loglevel -= '0';
+ break;
+ default:
+ /*
+ * Use loglevel -1 for cases where we just want to print to
+ * the screen.
+ */
+ loglevel = -1;
+ break;
+ }
+
+ if (loglevel >= efi_loglevel)
+ return 0;
+
+ if (loglevel >= 0)
+ efi_puts("EFI stub: ");
+
+ fmt = printk_skip_level(fmt);
+
+ va_start(args, fmt);
+ printed = vsnprintf(printf_buf, sizeof(printf_buf), fmt, args);
+ va_end(args);
+
+ efi_puts(printf_buf);
+ if (printed >= sizeof(printf_buf)) {
+ efi_puts("[Message truncated]\n");
+ return -1;
+ }
+
+ return printed;
+}
--
2.35.1
