linux/drivers/firmware/efi/efi-bgrt.c
Jan Beulich 6de47a5e37 efi/bgrt: Use efi_mem_type()
Avoid effectively open-coding the function.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:33 +02:00

92 lines
2.2 KiB
C

/*
* Copyright 2012 Intel Corporation
* Author: Josh Triplett <josh@joshtriplett.org>
*
* Based on the bgrt driver:
* Copyright 2012 Red Hat, Inc <mjg@redhat.com>
* Author: Matthew Garrett
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/efi.h>
#include <linux/efi-bgrt.h>
struct acpi_table_bgrt bgrt_tab;
size_t __initdata bgrt_image_size;
struct bmp_header {
u16 id;
u32 size;
} __packed;
void __init efi_bgrt_init(struct acpi_table_header *table)
{
void *image;
struct bmp_header bmp_header;
struct acpi_table_bgrt *bgrt = &bgrt_tab;
if (acpi_disabled)
return;
if (!efi_enabled(EFI_MEMMAP))
return;
if (table->length < sizeof(bgrt_tab)) {
pr_notice("Ignoring BGRT: invalid length %u (expected %zu)\n",
table->length, sizeof(bgrt_tab));
return;
}
*bgrt = *(struct acpi_table_bgrt *)table;
if (bgrt->version != 1) {
pr_notice("Ignoring BGRT: invalid version %u (expected 1)\n",
bgrt->version);
goto out;
}
if (bgrt->status & 0xfe) {
pr_notice("Ignoring BGRT: reserved status bits are non-zero %u\n",
bgrt->status);
goto out;
}
if (bgrt->image_type != 0) {
pr_notice("Ignoring BGRT: invalid image type %u (expected 0)\n",
bgrt->image_type);
goto out;
}
if (!bgrt->image_address) {
pr_notice("Ignoring BGRT: null image address\n");
goto out;
}
if (efi_mem_type(bgrt->image_address) != EFI_BOOT_SERVICES_DATA) {
pr_notice("Ignoring BGRT: invalid image address\n");
goto out;
}
image = early_memremap(bgrt->image_address, sizeof(bmp_header));
if (!image) {
pr_notice("Ignoring BGRT: failed to map image header memory\n");
goto out;
}
memcpy(&bmp_header, image, sizeof(bmp_header));
early_memunmap(image, sizeof(bmp_header));
if (bmp_header.id != 0x4d42) {
pr_notice("Ignoring BGRT: Incorrect BMP magic number 0x%x (expected 0x4d42)\n",
bmp_header.id);
goto out;
}
bgrt_image_size = bmp_header.size;
efi_mem_reserve(bgrt->image_address, bgrt_image_size);
return;
out:
memset(bgrt, 0, sizeof(bgrt_tab));
}