Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-27 22:51:35 +00:00
Code Issues Packages Projects Releases Wiki Activity
50428fdc53
linux/arch/powerpc/lib/code-patching.c
Mike Rapoport e31cf2f4ca mm: don't include asm/pgtable.h if linux/mm.h is already included 
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include <linux/mm.h>") ; do
		sed -i -e '/include <asm\/pgtable.h>/ d' $f
	done

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00

744 lines
20 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2008 Michael Ellerman, IBM Corporation.
*/
#include <linux/kernel.h>
#include <linux/kprobes.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/cpuhotplug.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <asm/tlbflush.h>
#include <asm/page.h>
#include <asm/code-patching.h>
#include <asm/setup.h>
#include <asm/inst.h>
static int __patch_instruction(struct ppc_inst *exec_addr, struct ppc_inst instr,
struct ppc_inst *patch_addr)
{
int err = 0;
if (!ppc_inst_prefixed(instr)) {
__put_user_asm(ppc_inst_val(instr), patch_addr, err, "stw");
} else {
__put_user_asm(ppc_inst_as_u64(instr), patch_addr, err, "std");
}
if (err)
return err;
asm ("dcbst 0, %0; sync; icbi 0,%1; sync; isync" :: "r" (patch_addr),
"r" (exec_addr));
return 0;
}
int raw_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
{
return __patch_instruction(addr, instr, addr);
}
#ifdef CONFIG_STRICT_KERNEL_RWX
static DEFINE_PER_CPU(struct vm_struct *, text_poke_area);
static int text_area_cpu_up(unsigned int cpu)
{
struct vm_struct *area;
area = get_vm_area(PAGE_SIZE, VM_ALLOC);
if (!area) {
WARN_ONCE(1, "Failed to create text area for cpu %d\n",
cpu);
return -1;
}
this_cpu_write(text_poke_area, area);
return 0;
}
static int text_area_cpu_down(unsigned int cpu)
{
free_vm_area(this_cpu_read(text_poke_area));
return 0;
}
/*
* Run as a late init call. This allows all the boot time patching to be done
* simply by patching the code, and then we're called here prior to
* mark_rodata_ro(), which happens after all init calls are run. Although
* BUG_ON() is rude, in this case it should only happen if ENOMEM, and we judge
* it as being preferable to a kernel that will crash later when someone tries
* to use patch_instruction().
*/
static int __init setup_text_poke_area(void)
{
BUG_ON(!cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
"powerpc/text_poke:online", text_area_cpu_up,
text_area_cpu_down));
return 0;
}
late_initcall(setup_text_poke_area);
/*
* This can be called for kernel text or a module.
*/
static int map_patch_area(void *addr, unsigned long text_poke_addr)
{
unsigned long pfn;
int err;
if (is_vmalloc_addr(addr))
pfn = vmalloc_to_pfn(addr);
else
pfn = __pa_symbol(addr) >> PAGE_SHIFT;
err = map_kernel_page(text_poke_addr, (pfn << PAGE_SHIFT), PAGE_KERNEL);
pr_devel("Mapped addr %lx with pfn %lx:%d\n", text_poke_addr, pfn, err);
if (err)
return -1;
return 0;
}
static inline int unmap_patch_area(unsigned long addr)
{
pte_t *ptep;
pmd_t *pmdp;
pud_t *pudp;
p4d_t *p4dp;
pgd_t *pgdp;
pgdp = pgd_offset_k(addr);
if (unlikely(!pgdp))
return -EINVAL;
p4dp = p4d_offset(pgdp, addr);
if (unlikely(!p4dp))
return -EINVAL;
pudp = pud_offset(p4dp, addr);
if (unlikely(!pudp))
return -EINVAL;
pmdp = pmd_offset(pudp, addr);
if (unlikely(!pmdp))
return -EINVAL;
ptep = pte_offset_kernel(pmdp, addr);
if (unlikely(!ptep))
return -EINVAL;
pr_devel("clearing mm %p, pte %p, addr %lx\n", &init_mm, ptep, addr);
/*
* In hash, pte_clear flushes the tlb, in radix, we have to
*/
pte_clear(&init_mm, addr, ptep);
flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
return 0;
}
static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
{
int err;
struct ppc_inst *patch_addr = NULL;
unsigned long flags;
unsigned long text_poke_addr;
unsigned long kaddr = (unsigned long)addr;
/*
* During early early boot patch_instruction is called
* when text_poke_area is not ready, but we still need
* to allow patching. We just do the plain old patching
*/
if (!this_cpu_read(text_poke_area))
return raw_patch_instruction(addr, instr);
local_irq_save(flags);
text_poke_addr = (unsigned long)__this_cpu_read(text_poke_area)->addr;
if (map_patch_area(addr, text_poke_addr)) {
err = -1;
goto out;
}
patch_addr = (struct ppc_inst *)(text_poke_addr + (kaddr & ~PAGE_MASK));
__patch_instruction(addr, instr, patch_addr);
err = unmap_patch_area(text_poke_addr);
if (err)
pr_warn("failed to unmap %lx\n", text_poke_addr);
out:
local_irq_restore(flags);
return err;
}
#else /* !CONFIG_STRICT_KERNEL_RWX */
static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
{
return raw_patch_instruction(addr, instr);
}
#endif /* CONFIG_STRICT_KERNEL_RWX */
int patch_instruction(struct ppc_inst *addr, struct ppc_inst instr)
{
/* Make sure we aren't patching a freed init section */
if (init_mem_is_free && init_section_contains(addr, 4)) {
pr_debug("Skipping init section patching addr: 0x%px\n", addr);
return 0;
}
return do_patch_instruction(addr, instr);
}
NOKPROBE_SYMBOL(patch_instruction);
int patch_branch(struct ppc_inst *addr, unsigned long target, int flags)
{
struct ppc_inst instr;
create_branch(&instr, addr, target, flags);
return patch_instruction(addr, instr);
}
bool is_offset_in_branch_range(long offset)
{
/*
* Powerpc branch instruction is :
*
* 0 6 30 31
* +---------+----------------+---+---+
* | opcode | LI |AA |LK |
* +---------+----------------+---+---+
* Where AA = 0 and LK = 0
*
* LI is a signed 24 bits integer. The real branch offset is computed
* by: imm32 = SignExtend(LI:'0b00', 32);
*
* So the maximum forward branch should be:
* (0x007fffff << 2) = 0x01fffffc = 0x1fffffc
* The maximum backward branch should be:
* (0xff800000 << 2) = 0xfe000000 = -0x2000000
*/
return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3));
}
/*
* Helper to check if a given instruction is a conditional branch
* Derived from the conditional checks in analyse_instr()
*/
bool is_conditional_branch(struct ppc_inst instr)
{
unsigned int opcode = ppc_inst_primary_opcode(instr);
if (opcode == 16) /* bc, bca, bcl, bcla */
return true;
if (opcode == 19) {
switch ((ppc_inst_val(instr) >> 1) & 0x3ff) {
case 16: /* bclr, bclrl */
case 528: /* bcctr, bcctrl */
case 560: /* bctar, bctarl */
return true;
}
}
return false;
}
NOKPROBE_SYMBOL(is_conditional_branch);
int create_branch(struct ppc_inst *instr,
const struct ppc_inst *addr,
unsigned long target, int flags)
{
long offset;
*instr = ppc_inst(0);
offset = target;
if (! (flags & BRANCH_ABSOLUTE))
offset = offset - (unsigned long)addr;
/* Check we can represent the target in the instruction format */
if (!is_offset_in_branch_range(offset))
return 1;
/* Mask out the flags and target, so they don't step on each other. */
*instr = ppc_inst(0x48000000 | (flags & 0x3) | (offset & 0x03FFFFFC));
return 0;
}
int create_cond_branch(struct ppc_inst *instr, const struct ppc_inst *addr,
unsigned long target, int flags)
{
long offset;
offset = target;
if (! (flags & BRANCH_ABSOLUTE))
offset = offset - (unsigned long)addr;
/* Check we can represent the target in the instruction format */
if (offset < -0x8000 || offset > 0x7FFF || offset & 0x3)
return 1;
/* Mask out the flags and target, so they don't step on each other. */
*instr = ppc_inst(0x40000000 | (flags & 0x3FF0003) | (offset & 0xFFFC));
return 0;
}
static unsigned int branch_opcode(struct ppc_inst instr)
{
return ppc_inst_primary_opcode(instr) & 0x3F;
}
static int instr_is_branch_iform(struct ppc_inst instr)
{
return branch_opcode(instr) == 18;
}
static int instr_is_branch_bform(struct ppc_inst instr)
{
return branch_opcode(instr) == 16;
}
int instr_is_relative_branch(struct ppc_inst instr)
{
if (ppc_inst_val(instr) & BRANCH_ABSOLUTE)
return 0;
return instr_is_branch_iform(instr) || instr_is_branch_bform(instr);
}
int instr_is_relative_link_branch(struct ppc_inst instr)
{
return instr_is_relative_branch(instr) && (ppc_inst_val(instr) & BRANCH_SET_LINK);
}
static unsigned long branch_iform_target(const struct ppc_inst *instr)
{
signed long imm;
imm = ppc_inst_val(*instr) & 0x3FFFFFC;
/* If the top bit of the immediate value is set this is negative */
if (imm & 0x2000000)
imm -= 0x4000000;
if ((ppc_inst_val(*instr) & BRANCH_ABSOLUTE) == 0)
imm += (unsigned long)instr;
return (unsigned long)imm;
}
static unsigned long branch_bform_target(const struct ppc_inst *instr)
{
signed long imm;
imm = ppc_inst_val(*instr) & 0xFFFC;
/* If the top bit of the immediate value is set this is negative */
if (imm & 0x8000)
imm -= 0x10000;
if ((ppc_inst_val(*instr) & BRANCH_ABSOLUTE) == 0)
imm += (unsigned long)instr;
return (unsigned long)imm;
}
unsigned long branch_target(const struct ppc_inst *instr)
{
if (instr_is_branch_iform(ppc_inst_read(instr)))
return branch_iform_target(instr);
else if (instr_is_branch_bform(ppc_inst_read(instr)))
return branch_bform_target(instr);
return 0;
}
int instr_is_branch_to_addr(const struct ppc_inst *instr, unsigned long addr)
{
if (instr_is_branch_iform(ppc_inst_read(instr)) ||
instr_is_branch_bform(ppc_inst_read(instr)))
return branch_target(instr) == addr;
return 0;
}
int translate_branch(struct ppc_inst *instr, const struct ppc_inst *dest,
const struct ppc_inst *src)
{
unsigned long target;
target = branch_target(src);
if (instr_is_branch_iform(ppc_inst_read(src)))
return create_branch(instr, dest, target,
ppc_inst_val(ppc_inst_read(src)));
else if (instr_is_branch_bform(ppc_inst_read(src)))
return create_cond_branch(instr, dest, target,
ppc_inst_val(ppc_inst_read(src)));
return 1;
}
#ifdef CONFIG_PPC_BOOK3E_64
void __patch_exception(int exc, unsigned long addr)
{
extern unsigned int interrupt_base_book3e;
unsigned int *ibase = &interrupt_base_book3e;
/* Our exceptions vectors start with a NOP and -then- a branch
* to deal with single stepping from userspace which stops on
* the second instruction. Thus we need to patch the second
* instruction of the exception, not the first one
*/
patch_branch((struct ppc_inst *)(ibase + (exc / 4) + 1), addr, 0);
}
#endif
#ifdef CONFIG_CODE_PATCHING_SELFTEST
static void __init test_trampoline(void)
{
asm ("nop;\n");
}
#define check(x) \
if (!(x)) printk("code-patching: test failed at line %d\n", __LINE__);
static void __init test_branch_iform(void)
{
int err;
struct ppc_inst instr;
unsigned long addr;
addr = (unsigned long)&instr;
/* The simplest case, branch to self, no flags */
check(instr_is_branch_iform(ppc_inst(0x48000000)));
/* All bits of target set, and flags */
check(instr_is_branch_iform(ppc_inst(0x4bffffff)));
/* High bit of opcode set, which is wrong */
check(!instr_is_branch_iform(ppc_inst(0xcbffffff)));
/* Middle bits of opcode set, which is wrong */
check(!instr_is_branch_iform(ppc_inst(0x7bffffff)));
/* Simplest case, branch to self with link */
check(instr_is_branch_iform(ppc_inst(0x48000001)));
/* All bits of targets set */
check(instr_is_branch_iform(ppc_inst(0x4bfffffd)));
/* Some bits of targets set */
check(instr_is_branch_iform(ppc_inst(0x4bff00fd)));
/* Must be a valid branch to start with */
check(!instr_is_branch_iform(ppc_inst(0x7bfffffd)));
/* Absolute branch to 0x100 */
instr = ppc_inst(0x48000103);
check(instr_is_branch_to_addr(&instr, 0x100));
/* Absolute branch to 0x420fc */
instr = ppc_inst(0x480420ff);
check(instr_is_branch_to_addr(&instr, 0x420fc));
/* Maximum positive relative branch, + 20MB - 4B */
instr = ppc_inst(0x49fffffc);
check(instr_is_branch_to_addr(&instr, addr + 0x1FFFFFC));
/* Smallest negative relative branch, - 4B */
instr = ppc_inst(0x4bfffffc);
check(instr_is_branch_to_addr(&instr, addr - 4));
/* Largest negative relative branch, - 32 MB */
instr = ppc_inst(0x4a000000);
check(instr_is_branch_to_addr(&instr, addr - 0x2000000));
/* Branch to self, with link */
err = create_branch(&instr, &instr, addr, BRANCH_SET_LINK);
check(instr_is_branch_to_addr(&instr, addr));
/* Branch to self - 0x100, with link */
err = create_branch(&instr, &instr, addr - 0x100, BRANCH_SET_LINK);
check(instr_is_branch_to_addr(&instr, addr - 0x100));
/* Branch to self + 0x100, no link */
err = create_branch(&instr, &instr, addr + 0x100, 0);
check(instr_is_branch_to_addr(&instr, addr + 0x100));
/* Maximum relative negative offset, - 32 MB */
err = create_branch(&instr, &instr, addr - 0x2000000, BRANCH_SET_LINK);
check(instr_is_branch_to_addr(&instr, addr - 0x2000000));
/* Out of range relative negative offset, - 32 MB + 4*/
err = create_branch(&instr, &instr, addr - 0x2000004, BRANCH_SET_LINK);
check(err);
/* Out of range relative positive offset, + 32 MB */
err = create_branch(&instr, &instr, addr + 0x2000000, BRANCH_SET_LINK);
check(err);
/* Unaligned target */
err = create_branch(&instr, &instr, addr + 3, BRANCH_SET_LINK);
check(err);
/* Check flags are masked correctly */
err = create_branch(&instr, &instr, addr, 0xFFFFFFFC);
check(instr_is_branch_to_addr(&instr, addr));
check(ppc_inst_equal(instr, ppc_inst(0x48000000)));
}
static void __init test_create_function_call(void)
{
struct ppc_inst *iptr;
unsigned long dest;
struct ppc_inst instr;
/* Check we can create a function call */
iptr = (struct ppc_inst *)ppc_function_entry(test_trampoline);
dest = ppc_function_entry(test_create_function_call);
create_branch(&instr, iptr, dest, BRANCH_SET_LINK);
patch_instruction(iptr, instr);
check(instr_is_branch_to_addr(iptr, dest));
}
static void __init test_branch_bform(void)
{
int err;
unsigned long addr;
struct ppc_inst *iptr, instr;
unsigned int flags;
iptr = &instr;
addr = (unsigned long)iptr;
/* The simplest case, branch to self, no flags */
check(instr_is_branch_bform(ppc_inst(0x40000000)));
/* All bits of target set, and flags */
check(instr_is_branch_bform(ppc_inst(0x43ffffff)));
/* High bit of opcode set, which is wrong */
check(!instr_is_branch_bform(ppc_inst(0xc3ffffff)));
/* Middle bits of opcode set, which is wrong */
check(!instr_is_branch_bform(ppc_inst(0x7bffffff)));
/* Absolute conditional branch to 0x100 */
instr = ppc_inst(0x43ff0103);
check(instr_is_branch_to_addr(&instr, 0x100));
/* Absolute conditional branch to 0x20fc */
instr = ppc_inst(0x43ff20ff);
check(instr_is_branch_to_addr(&instr, 0x20fc));
/* Maximum positive relative conditional branch, + 32 KB - 4B */
instr = ppc_inst(0x43ff7ffc);
check(instr_is_branch_to_addr(&instr, addr + 0x7FFC));
/* Smallest negative relative conditional branch, - 4B */
instr = ppc_inst(0x43fffffc);
check(instr_is_branch_to_addr(&instr, addr - 4));
/* Largest negative relative conditional branch, - 32 KB */
instr = ppc_inst(0x43ff8000);
check(instr_is_branch_to_addr(&instr, addr - 0x8000));
/* All condition code bits set & link */
flags = 0x3ff000 | BRANCH_SET_LINK;
/* Branch to self */
err = create_cond_branch(&instr, iptr, addr, flags);
check(instr_is_branch_to_addr(&instr, addr));
/* Branch to self - 0x100 */
err = create_cond_branch(&instr, iptr, addr - 0x100, flags);
check(instr_is_branch_to_addr(&instr, addr - 0x100));
/* Branch to self + 0x100 */
err = create_cond_branch(&instr, iptr, addr + 0x100, flags);
check(instr_is_branch_to_addr(&instr, addr + 0x100));
/* Maximum relative negative offset, - 32 KB */
err = create_cond_branch(&instr, iptr, addr - 0x8000, flags);
check(instr_is_branch_to_addr(&instr, addr - 0x8000));
/* Out of range relative negative offset, - 32 KB + 4*/
err = create_cond_branch(&instr, iptr, addr - 0x8004, flags);
check(err);
/* Out of range relative positive offset, + 32 KB */
err = create_cond_branch(&instr, iptr, addr + 0x8000, flags);
check(err);
/* Unaligned target */
err = create_cond_branch(&instr, iptr, addr + 3, flags);
check(err);
/* Check flags are masked correctly */
err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC);
check(instr_is_branch_to_addr(&instr, addr));
check(ppc_inst_equal(instr, ppc_inst(0x43FF0000)));
}
static void __init test_translate_branch(void)
{
unsigned long addr;
void *p, *q;
struct ppc_inst instr;
void *buf;
buf = vmalloc(PAGE_ALIGN(0x2000000 + 1));
check(buf);
if (!buf)
return;
/* Simple case, branch to self moved a little */
p = buf;
addr = (unsigned long)p;
patch_branch(p, addr, 0);
check(instr_is_branch_to_addr(p, addr));
q = p + 4;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(q, addr));
/* Maximum negative case, move b . to addr + 32 MB */
p = buf;
addr = (unsigned long)p;
patch_branch(p, addr, 0);
q = buf + 0x2000000;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x4a000000)));
/* Maximum positive case, move x to x - 32 MB + 4 */
p = buf + 0x2000000;
addr = (unsigned long)p;
patch_branch(p, addr, 0);
q = buf + 4;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x49fffffc)));
/* Jump to x + 16 MB moved to x + 20 MB */
p = buf;
addr = 0x1000000 + (unsigned long)buf;
patch_branch(p, addr, BRANCH_SET_LINK);
q = buf + 0x1400000;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
/* Jump to x + 16 MB moved to x - 16 MB + 4 */
p = buf + 0x1000000;
addr = 0x2000000 + (unsigned long)buf;
patch_branch(p, addr, 0);
q = buf + 4;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
/* Conditional branch tests */
/* Simple case, branch to self moved a little */
p = buf;
addr = (unsigned long)p;
create_cond_branch(&instr, p, addr, 0);
patch_instruction(p, instr);
check(instr_is_branch_to_addr(p, addr));
q = buf + 4;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(q, addr));
/* Maximum negative case, move b . to addr + 32 KB */
p = buf;
addr = (unsigned long)p;
create_cond_branch(&instr, p, addr, 0xFFFFFFFC);
patch_instruction(p, instr);
q = buf + 0x8000;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff8000)));
/* Maximum positive case, move x to x - 32 KB + 4 */
p = buf + 0x8000;
addr = (unsigned long)p;
create_cond_branch(&instr, p, addr, 0xFFFFFFFC);
patch_instruction(p, instr);
q = buf + 4;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff7ffc)));
/* Jump to x + 12 KB moved to x + 20 KB */
p = buf;
addr = 0x3000 + (unsigned long)buf;
create_cond_branch(&instr, p, addr, BRANCH_SET_LINK);
patch_instruction(p, instr);
q = buf + 0x5000;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
/* Jump to x + 8 KB moved to x - 8 KB + 4 */
p = buf + 0x2000;
addr = 0x4000 + (unsigned long)buf;
create_cond_branch(&instr, p, addr, 0);
patch_instruction(p, instr);
q = buf + 4;
translate_branch(&instr, q, p);
patch_instruction(q, instr);
check(instr_is_branch_to_addr(p, addr));
check(instr_is_branch_to_addr(q, addr));
/* Free the buffer we were using */
vfree(buf);
}
#ifdef CONFIG_PPC64
static void __init test_prefixed_patching(void)
{
extern unsigned int code_patching_test1[];
extern unsigned int code_patching_test1_expected[];
extern unsigned int end_code_patching_test1[];
__patch_instruction((struct ppc_inst *)code_patching_test1,
ppc_inst_prefix(OP_PREFIX << 26, 0x00000000),
(struct ppc_inst *)code_patching_test1);
check(!memcmp(code_patching_test1,
code_patching_test1_expected,
sizeof(unsigned int) *
(end_code_patching_test1 - code_patching_test1)));
}
#else
static inline void test_prefixed_patching(void) {}
#endif
static int __init test_code_patching(void)
{
printk(KERN_DEBUG "Running code patching self-tests ...\n");
test_branch_iform();
test_branch_bform();
test_create_function_call();
test_translate_branch();
test_prefixed_patching();
return 0;
}
late_initcall(test_code_patching);
#endif /* CONFIG_CODE_PATCHING_SELFTEST */
Reference in New Issue View Git Blame Copy Permalink