352 строки
11 KiB
C
352 строки
11 KiB
C
/*
|
|
* Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
|
|
*
|
|
* Modifications for ppc64:
|
|
* Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
|
|
*
|
|
* Copyright 2008 Michael Ellerman, IBM Corporation.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/init.h>
|
|
#include <asm/cputable.h>
|
|
#include <asm/code-patching.h>
|
|
|
|
|
|
struct fixup_entry {
|
|
unsigned long mask;
|
|
unsigned long value;
|
|
long start_off;
|
|
long end_off;
|
|
long alt_start_off;
|
|
long alt_end_off;
|
|
};
|
|
|
|
static unsigned int *calc_addr(struct fixup_entry *fcur, long offset)
|
|
{
|
|
/*
|
|
* We store the offset to the code as a negative offset from
|
|
* the start of the alt_entry, to support the VDSO. This
|
|
* routine converts that back into an actual address.
|
|
*/
|
|
return (unsigned int *)((unsigned long)fcur + offset);
|
|
}
|
|
|
|
static int patch_alt_instruction(unsigned int *src, unsigned int *dest,
|
|
unsigned int *alt_start, unsigned int *alt_end)
|
|
{
|
|
unsigned int instr;
|
|
|
|
instr = *src;
|
|
|
|
if (instr_is_relative_branch(*src)) {
|
|
unsigned int *target = (unsigned int *)branch_target(src);
|
|
|
|
/* Branch within the section doesn't need translating */
|
|
if (target < alt_start || target >= alt_end) {
|
|
instr = translate_branch(dest, src);
|
|
if (!instr)
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
patch_instruction(dest, instr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
|
|
{
|
|
unsigned int *start, *end, *alt_start, *alt_end, *src, *dest;
|
|
|
|
start = calc_addr(fcur, fcur->start_off);
|
|
end = calc_addr(fcur, fcur->end_off);
|
|
alt_start = calc_addr(fcur, fcur->alt_start_off);
|
|
alt_end = calc_addr(fcur, fcur->alt_end_off);
|
|
|
|
if ((alt_end - alt_start) > (end - start))
|
|
return 1;
|
|
|
|
if ((value & fcur->mask) == fcur->value)
|
|
return 0;
|
|
|
|
src = alt_start;
|
|
dest = start;
|
|
|
|
for (; src < alt_end; src++, dest++) {
|
|
if (patch_alt_instruction(src, dest, alt_start, alt_end))
|
|
return 1;
|
|
}
|
|
|
|
for (; dest < end; dest++)
|
|
patch_instruction(dest, PPC_NOP_INSTR);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
|
|
{
|
|
struct fixup_entry *fcur, *fend;
|
|
|
|
fcur = fixup_start;
|
|
fend = fixup_end;
|
|
|
|
for (; fcur < fend; fcur++) {
|
|
if (patch_feature_section(value, fcur)) {
|
|
WARN_ON(1);
|
|
printk("Unable to patch feature section at %p - %p" \
|
|
" with %p - %p\n",
|
|
calc_addr(fcur, fcur->start_off),
|
|
calc_addr(fcur, fcur->end_off),
|
|
calc_addr(fcur, fcur->alt_start_off),
|
|
calc_addr(fcur, fcur->alt_end_off));
|
|
}
|
|
}
|
|
}
|
|
|
|
void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
|
|
{
|
|
unsigned int *start, *end, *dest;
|
|
|
|
if (!(value & CPU_FTR_LWSYNC))
|
|
return ;
|
|
|
|
start = fixup_start;
|
|
end = fixup_end;
|
|
|
|
for (; start < end; start++) {
|
|
dest = (void *)start + *start;
|
|
patch_instruction(dest, PPC_LWSYNC_INSTR);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_FTR_FIXUP_SELFTEST
|
|
|
|
#define check(x) \
|
|
if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
|
|
|
|
/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
|
|
static struct fixup_entry fixup;
|
|
|
|
static long calc_offset(struct fixup_entry *entry, unsigned int *p)
|
|
{
|
|
return (unsigned long)p - (unsigned long)entry;
|
|
}
|
|
|
|
void test_basic_patching(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test1;
|
|
extern unsigned int end_ftr_fixup_test1;
|
|
extern unsigned int ftr_fixup_test1_orig;
|
|
extern unsigned int ftr_fixup_test1_expected;
|
|
int size = &end_ftr_fixup_test1 - &ftr_fixup_test1;
|
|
|
|
fixup.value = fixup.mask = 8;
|
|
fixup.start_off = calc_offset(&fixup, &ftr_fixup_test1 + 1);
|
|
fixup.end_off = calc_offset(&fixup, &ftr_fixup_test1 + 2);
|
|
fixup.alt_start_off = fixup.alt_end_off = 0;
|
|
|
|
/* Sanity check */
|
|
check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
|
|
|
|
/* Check we don't patch if the value matches */
|
|
patch_feature_section(8, &fixup);
|
|
check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
|
|
|
|
/* Check we do patch if the value doesn't match */
|
|
patch_feature_section(0, &fixup);
|
|
check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0);
|
|
|
|
/* Check we do patch if the mask doesn't match */
|
|
memcpy(&ftr_fixup_test1, &ftr_fixup_test1_orig, size);
|
|
check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0);
|
|
patch_feature_section(~8, &fixup);
|
|
check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_patching(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test2;
|
|
extern unsigned int end_ftr_fixup_test2;
|
|
extern unsigned int ftr_fixup_test2_orig;
|
|
extern unsigned int ftr_fixup_test2_alt;
|
|
extern unsigned int ftr_fixup_test2_expected;
|
|
int size = &end_ftr_fixup_test2 - &ftr_fixup_test2;
|
|
|
|
fixup.value = fixup.mask = 0xF;
|
|
fixup.start_off = calc_offset(&fixup, &ftr_fixup_test2 + 1);
|
|
fixup.end_off = calc_offset(&fixup, &ftr_fixup_test2 + 2);
|
|
fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test2_alt);
|
|
fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test2_alt + 1);
|
|
|
|
/* Sanity check */
|
|
check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
|
|
|
|
/* Check we don't patch if the value matches */
|
|
patch_feature_section(0xF, &fixup);
|
|
check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
|
|
|
|
/* Check we do patch if the value doesn't match */
|
|
patch_feature_section(0, &fixup);
|
|
check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0);
|
|
|
|
/* Check we do patch if the mask doesn't match */
|
|
memcpy(&ftr_fixup_test2, &ftr_fixup_test2_orig, size);
|
|
check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0);
|
|
patch_feature_section(~0xF, &fixup);
|
|
check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_too_big(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test3;
|
|
extern unsigned int end_ftr_fixup_test3;
|
|
extern unsigned int ftr_fixup_test3_orig;
|
|
extern unsigned int ftr_fixup_test3_alt;
|
|
int size = &end_ftr_fixup_test3 - &ftr_fixup_test3;
|
|
|
|
fixup.value = fixup.mask = 0xC;
|
|
fixup.start_off = calc_offset(&fixup, &ftr_fixup_test3 + 1);
|
|
fixup.end_off = calc_offset(&fixup, &ftr_fixup_test3 + 2);
|
|
fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test3_alt);
|
|
fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test3_alt + 2);
|
|
|
|
/* Sanity check */
|
|
check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
|
|
|
|
/* Expect nothing to be patched, and the error returned to us */
|
|
check(patch_feature_section(0xF, &fixup) == 1);
|
|
check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
|
|
check(patch_feature_section(0, &fixup) == 1);
|
|
check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
|
|
check(patch_feature_section(~0xF, &fixup) == 1);
|
|
check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_too_small(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test4;
|
|
extern unsigned int end_ftr_fixup_test4;
|
|
extern unsigned int ftr_fixup_test4_orig;
|
|
extern unsigned int ftr_fixup_test4_alt;
|
|
extern unsigned int ftr_fixup_test4_expected;
|
|
int size = &end_ftr_fixup_test4 - &ftr_fixup_test4;
|
|
unsigned long flag;
|
|
|
|
/* Check a high-bit flag */
|
|
flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
|
|
fixup.value = fixup.mask = flag;
|
|
fixup.start_off = calc_offset(&fixup, &ftr_fixup_test4 + 1);
|
|
fixup.end_off = calc_offset(&fixup, &ftr_fixup_test4 + 5);
|
|
fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test4_alt);
|
|
fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test4_alt + 2);
|
|
|
|
/* Sanity check */
|
|
check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
|
|
|
|
/* Check we don't patch if the value matches */
|
|
patch_feature_section(flag, &fixup);
|
|
check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
|
|
|
|
/* Check we do patch if the value doesn't match */
|
|
patch_feature_section(0, &fixup);
|
|
check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0);
|
|
|
|
/* Check we do patch if the mask doesn't match */
|
|
memcpy(&ftr_fixup_test4, &ftr_fixup_test4_orig, size);
|
|
check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0);
|
|
patch_feature_section(~flag, &fixup);
|
|
check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_with_branch(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test5;
|
|
extern unsigned int end_ftr_fixup_test5;
|
|
extern unsigned int ftr_fixup_test5_expected;
|
|
int size = &end_ftr_fixup_test5 - &ftr_fixup_test5;
|
|
|
|
check(memcmp(&ftr_fixup_test5, &ftr_fixup_test5_expected, size) == 0);
|
|
}
|
|
|
|
static void test_alternative_case_with_external_branch(void)
|
|
{
|
|
extern unsigned int ftr_fixup_test6;
|
|
extern unsigned int end_ftr_fixup_test6;
|
|
extern unsigned int ftr_fixup_test6_expected;
|
|
int size = &end_ftr_fixup_test6 - &ftr_fixup_test6;
|
|
|
|
check(memcmp(&ftr_fixup_test6, &ftr_fixup_test6_expected, size) == 0);
|
|
}
|
|
|
|
static void test_cpu_macros(void)
|
|
{
|
|
extern void ftr_fixup_test_FTR_macros;
|
|
extern void ftr_fixup_test_FTR_macros_expected;
|
|
unsigned long size = &ftr_fixup_test_FTR_macros_expected -
|
|
&ftr_fixup_test_FTR_macros;
|
|
|
|
/* The fixups have already been done for us during boot */
|
|
check(memcmp(&ftr_fixup_test_FTR_macros,
|
|
&ftr_fixup_test_FTR_macros_expected, size) == 0);
|
|
}
|
|
|
|
static void test_fw_macros(void)
|
|
{
|
|
#ifdef CONFIG_PPC64
|
|
extern void ftr_fixup_test_FW_FTR_macros;
|
|
extern void ftr_fixup_test_FW_FTR_macros_expected;
|
|
unsigned long size = &ftr_fixup_test_FW_FTR_macros_expected -
|
|
&ftr_fixup_test_FW_FTR_macros;
|
|
|
|
/* The fixups have already been done for us during boot */
|
|
check(memcmp(&ftr_fixup_test_FW_FTR_macros,
|
|
&ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
|
|
#endif
|
|
}
|
|
|
|
static void test_lwsync_macros(void)
|
|
{
|
|
extern void lwsync_fixup_test;
|
|
extern void end_lwsync_fixup_test;
|
|
extern void lwsync_fixup_test_expected_LWSYNC;
|
|
extern void lwsync_fixup_test_expected_SYNC;
|
|
unsigned long size = &end_lwsync_fixup_test -
|
|
&lwsync_fixup_test;
|
|
|
|
/* The fixups have already been done for us during boot */
|
|
if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
|
|
check(memcmp(&lwsync_fixup_test,
|
|
&lwsync_fixup_test_expected_LWSYNC, size) == 0);
|
|
} else {
|
|
check(memcmp(&lwsync_fixup_test,
|
|
&lwsync_fixup_test_expected_SYNC, size) == 0);
|
|
}
|
|
}
|
|
|
|
static int __init test_feature_fixups(void)
|
|
{
|
|
printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
|
|
|
|
test_basic_patching();
|
|
test_alternative_patching();
|
|
test_alternative_case_too_big();
|
|
test_alternative_case_too_small();
|
|
test_alternative_case_with_branch();
|
|
test_alternative_case_with_external_branch();
|
|
test_cpu_macros();
|
|
test_fw_macros();
|
|
test_lwsync_macros();
|
|
|
|
return 0;
|
|
}
|
|
late_initcall(test_feature_fixups);
|
|
|
|
#endif /* CONFIG_FTR_FIXUP_SELFTEST */
|