diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/powerpc/lib/code-patching.c')
| -rw-r--r-- | ANDROID_3.4.5/arch/powerpc/lib/code-patching.c | 449 |
1 files changed, 0 insertions, 449 deletions
diff --git a/ANDROID_3.4.5/arch/powerpc/lib/code-patching.c b/ANDROID_3.4.5/arch/powerpc/lib/code-patching.c deleted file mode 100644 index 7c975d43..00000000 --- a/ANDROID_3.4.5/arch/powerpc/lib/code-patching.c +++ /dev/null @@ -1,449 +0,0 @@ -/* - * 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/vmalloc.h> -#include <linux/init.h> -#include <linux/mm.h> -#include <asm/page.h> -#include <asm/code-patching.h> - - -void patch_instruction(unsigned int *addr, unsigned int instr) -{ - *addr = instr; - asm ("dcbst 0, %0; sync; icbi 0,%0; sync; isync" : : "r" (addr)); -} - -void patch_branch(unsigned int *addr, unsigned long target, int flags) -{ - patch_instruction(addr, create_branch(addr, target, flags)); -} - -unsigned int create_branch(const unsigned int *addr, - unsigned long target, int flags) -{ - unsigned int instruction; - 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 < -0x2000000 || offset > 0x1fffffc || offset & 0x3) - return 0; - - /* Mask out the flags and target, so they don't step on each other. */ - instruction = 0x48000000 | (flags & 0x3) | (offset & 0x03FFFFFC); - - return instruction; -} - -unsigned int create_cond_branch(const unsigned int *addr, - unsigned long target, int flags) -{ - unsigned int instruction; - 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 0; - - /* Mask out the flags and target, so they don't step on each other. */ - instruction = 0x40000000 | (flags & 0x3FF0003) | (offset & 0xFFFC); - - return instruction; -} - -static unsigned int branch_opcode(unsigned int instr) -{ - return (instr >> 26) & 0x3F; -} - -static int instr_is_branch_iform(unsigned int instr) -{ - return branch_opcode(instr) == 18; -} - -static int instr_is_branch_bform(unsigned int instr) -{ - return branch_opcode(instr) == 16; -} - -int instr_is_relative_branch(unsigned int instr) -{ - if (instr & BRANCH_ABSOLUTE) - return 0; - - return instr_is_branch_iform(instr) || instr_is_branch_bform(instr); -} - -static unsigned long branch_iform_target(const unsigned int *instr) -{ - signed long imm; - - imm = *instr & 0x3FFFFFC; - - /* If the top bit of the immediate value is set this is negative */ - if (imm & 0x2000000) - imm -= 0x4000000; - - if ((*instr & BRANCH_ABSOLUTE) == 0) - imm += (unsigned long)instr; - - return (unsigned long)imm; -} - -static unsigned long branch_bform_target(const unsigned int *instr) -{ - signed long imm; - - imm = *instr & 0xFFFC; - - /* If the top bit of the immediate value is set this is negative */ - if (imm & 0x8000) - imm -= 0x10000; - - if ((*instr & BRANCH_ABSOLUTE) == 0) - imm += (unsigned long)instr; - - return (unsigned long)imm; -} - -unsigned long branch_target(const unsigned int *instr) -{ - if (instr_is_branch_iform(*instr)) - return branch_iform_target(instr); - else if (instr_is_branch_bform(*instr)) - return branch_bform_target(instr); - - return 0; -} - -int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr) -{ - if (instr_is_branch_iform(*instr) || instr_is_branch_bform(*instr)) - return branch_target(instr) == addr; - - return 0; -} - -unsigned int translate_branch(const unsigned int *dest, const unsigned int *src) -{ - unsigned long target; - - target = branch_target(src); - - if (instr_is_branch_iform(*src)) - return create_branch(dest, target, *src); - else if (instr_is_branch_bform(*src)) - return create_cond_branch(dest, target, *src); - - return 0; -} - - -#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) -{ - unsigned int instr; - unsigned long addr; - - addr = (unsigned long)&instr; - - /* The simplest case, branch to self, no flags */ - check(instr_is_branch_iform(0x48000000)); - /* All bits of target set, and flags */ - check(instr_is_branch_iform(0x4bffffff)); - /* High bit of opcode set, which is wrong */ - check(!instr_is_branch_iform(0xcbffffff)); - /* Middle bits of opcode set, which is wrong */ - check(!instr_is_branch_iform(0x7bffffff)); - - /* Simplest case, branch to self with link */ - check(instr_is_branch_iform(0x48000001)); - /* All bits of targets set */ - check(instr_is_branch_iform(0x4bfffffd)); - /* Some bits of targets set */ - check(instr_is_branch_iform(0x4bff00fd)); - /* Must be a valid branch to start with */ - check(!instr_is_branch_iform(0x7bfffffd)); - - /* Absolute branch to 0x100 */ - instr = 0x48000103; - check(instr_is_branch_to_addr(&instr, 0x100)); - /* Absolute branch to 0x420fc */ - instr = 0x480420ff; - check(instr_is_branch_to_addr(&instr, 0x420fc)); - /* Maximum positive relative branch, + 20MB - 4B */ - instr = 0x49fffffc; - check(instr_is_branch_to_addr(&instr, addr + 0x1FFFFFC)); - /* Smallest negative relative branch, - 4B */ - instr = 0x4bfffffc; - check(instr_is_branch_to_addr(&instr, addr - 4)); - /* Largest negative relative branch, - 32 MB */ - instr = 0x4a000000; - check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); - - /* Branch to self, with link */ - instr = create_branch(&instr, addr, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr)); - - /* Branch to self - 0x100, with link */ - instr = create_branch(&instr, addr - 0x100, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr - 0x100)); - - /* Branch to self + 0x100, no link */ - instr = create_branch(&instr, addr + 0x100, 0); - check(instr_is_branch_to_addr(&instr, addr + 0x100)); - - /* Maximum relative negative offset, - 32 MB */ - instr = create_branch(&instr, addr - 0x2000000, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); - - /* Out of range relative negative offset, - 32 MB + 4*/ - instr = create_branch(&instr, addr - 0x2000004, BRANCH_SET_LINK); - check(instr == 0); - - /* Out of range relative positive offset, + 32 MB */ - instr = create_branch(&instr, addr + 0x2000000, BRANCH_SET_LINK); - check(instr == 0); - - /* Unaligned target */ - instr = create_branch(&instr, addr + 3, BRANCH_SET_LINK); - check(instr == 0); - - /* Check flags are masked correctly */ - instr = create_branch(&instr, addr, 0xFFFFFFFC); - check(instr_is_branch_to_addr(&instr, addr)); - check(instr == 0x48000000); -} - -static void __init test_create_function_call(void) -{ - unsigned int *iptr; - unsigned long dest; - - /* Check we can create a function call */ - iptr = (unsigned int *)ppc_function_entry(test_trampoline); - dest = ppc_function_entry(test_create_function_call); - patch_instruction(iptr, create_branch(iptr, dest, BRANCH_SET_LINK)); - check(instr_is_branch_to_addr(iptr, dest)); -} - -static void __init test_branch_bform(void) -{ - unsigned long addr; - unsigned int *iptr, instr, flags; - - iptr = &instr; - addr = (unsigned long)iptr; - - /* The simplest case, branch to self, no flags */ - check(instr_is_branch_bform(0x40000000)); - /* All bits of target set, and flags */ - check(instr_is_branch_bform(0x43ffffff)); - /* High bit of opcode set, which is wrong */ - check(!instr_is_branch_bform(0xc3ffffff)); - /* Middle bits of opcode set, which is wrong */ - check(!instr_is_branch_bform(0x7bffffff)); - - /* Absolute conditional branch to 0x100 */ - instr = 0x43ff0103; - check(instr_is_branch_to_addr(&instr, 0x100)); - /* Absolute conditional branch to 0x20fc */ - instr = 0x43ff20ff; - check(instr_is_branch_to_addr(&instr, 0x20fc)); - /* Maximum positive relative conditional branch, + 32 KB - 4B */ - instr = 0x43ff7ffc; - check(instr_is_branch_to_addr(&instr, addr + 0x7FFC)); - /* Smallest negative relative conditional branch, - 4B */ - instr = 0x43fffffc; - check(instr_is_branch_to_addr(&instr, addr - 4)); - /* Largest negative relative conditional branch, - 32 KB */ - instr = 0x43ff8000; - check(instr_is_branch_to_addr(&instr, addr - 0x8000)); - - /* All condition code bits set & link */ - flags = 0x3ff000 | BRANCH_SET_LINK; - - /* Branch to self */ - instr = create_cond_branch(iptr, addr, flags); - check(instr_is_branch_to_addr(&instr, addr)); - - /* Branch to self - 0x100 */ - instr = create_cond_branch(iptr, addr - 0x100, flags); - check(instr_is_branch_to_addr(&instr, addr - 0x100)); - - /* Branch to self + 0x100 */ - instr = create_cond_branch(iptr, addr + 0x100, flags); - check(instr_is_branch_to_addr(&instr, addr + 0x100)); - - /* Maximum relative negative offset, - 32 KB */ - instr = create_cond_branch(iptr, addr - 0x8000, flags); - check(instr_is_branch_to_addr(&instr, addr - 0x8000)); - - /* Out of range relative negative offset, - 32 KB + 4*/ - instr = create_cond_branch(iptr, addr - 0x8004, flags); - check(instr == 0); - - /* Out of range relative positive offset, + 32 KB */ - instr = create_cond_branch(iptr, addr + 0x8000, flags); - check(instr == 0); - - /* Unaligned target */ - instr = create_cond_branch(iptr, addr + 3, flags); - check(instr == 0); - - /* Check flags are masked correctly */ - instr = create_cond_branch(iptr, addr, 0xFFFFFFFC); - check(instr_is_branch_to_addr(&instr, addr)); - check(instr == 0x43FF0000); -} - -static void __init test_translate_branch(void) -{ - unsigned long addr; - unsigned int *p, *q; - 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 + 1; - patch_instruction(q, translate_branch(q, p)); - 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; - patch_instruction(q, translate_branch(q, p)); - check(instr_is_branch_to_addr(p, addr)); - check(instr_is_branch_to_addr(q, addr)); - check(*q == 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; - patch_instruction(q, translate_branch(q, p)); - check(instr_is_branch_to_addr(p, addr)); - check(instr_is_branch_to_addr(q, addr)); - check(*q == 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; - patch_instruction(q, translate_branch(q, p)); - 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; - patch_instruction(q, translate_branch(q, p)); - 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; - patch_instruction(p, create_cond_branch(p, addr, 0)); - check(instr_is_branch_to_addr(p, addr)); - q = p + 1; - patch_instruction(q, translate_branch(q, p)); - check(instr_is_branch_to_addr(q, addr)); - - /* Maximum negative case, move b . to addr + 32 KB */ - p = buf; - addr = (unsigned long)p; - patch_instruction(p, create_cond_branch(p, addr, 0xFFFFFFFC)); - q = buf + 0x8000; - patch_instruction(q, translate_branch(q, p)); - check(instr_is_branch_to_addr(p, addr)); - check(instr_is_branch_to_addr(q, addr)); - check(*q == 0x43ff8000); - - /* Maximum positive case, move x to x - 32 KB + 4 */ - p = buf + 0x8000; - addr = (unsigned long)p; - patch_instruction(p, create_cond_branch(p, addr, 0xFFFFFFFC)); - q = buf + 4; - patch_instruction(q, translate_branch(q, p)); - check(instr_is_branch_to_addr(p, addr)); - check(instr_is_branch_to_addr(q, addr)); - check(*q == 0x43ff7ffc); - - /* Jump to x + 12 KB moved to x + 20 KB */ - p = buf; - addr = 0x3000 + (unsigned long)buf; - patch_instruction(p, create_cond_branch(p, addr, BRANCH_SET_LINK)); - q = buf + 0x5000; - patch_instruction(q, translate_branch(q, p)); - 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; - patch_instruction(p, create_cond_branch(p, addr, 0)); - q = buf + 4; - patch_instruction(q, translate_branch(q, p)); - check(instr_is_branch_to_addr(p, addr)); - check(instr_is_branch_to_addr(q, addr)); - - /* Free the buffer we were using */ - vfree(buf); -} - -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(); - - return 0; -} -late_initcall(test_code_patching); - -#endif /* CONFIG_CODE_PATCHING_SELFTEST */ |