mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
190 lines
5.5 KiB
190 lines
5.5 KiB
/* SPDX-License-Identifier: GPL-2.0-or-later */ |
|
#ifndef _ASM_POWERPC_CODE_PATCHING_H |
|
#define _ASM_POWERPC_CODE_PATCHING_H |
|
|
|
/* |
|
* Copyright 2008, Michael Ellerman, IBM Corporation. |
|
*/ |
|
|
|
#include <asm/types.h> |
|
#include <asm/ppc-opcode.h> |
|
#include <linux/string.h> |
|
#include <linux/kallsyms.h> |
|
#include <asm/asm-compat.h> |
|
#include <asm/inst.h> |
|
|
|
/* Flags for create_branch: |
|
* "b" == create_branch(addr, target, 0); |
|
* "ba" == create_branch(addr, target, BRANCH_ABSOLUTE); |
|
* "bl" == create_branch(addr, target, BRANCH_SET_LINK); |
|
* "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK); |
|
*/ |
|
#define BRANCH_SET_LINK 0x1 |
|
#define BRANCH_ABSOLUTE 0x2 |
|
|
|
bool is_offset_in_branch_range(long offset); |
|
int create_branch(struct ppc_inst *instr, const struct ppc_inst *addr, |
|
unsigned long target, int flags); |
|
int create_cond_branch(struct ppc_inst *instr, const struct ppc_inst *addr, |
|
unsigned long target, int flags); |
|
int patch_branch(struct ppc_inst *addr, unsigned long target, int flags); |
|
int patch_instruction(struct ppc_inst *addr, struct ppc_inst instr); |
|
int raw_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr); |
|
|
|
static inline unsigned long patch_site_addr(s32 *site) |
|
{ |
|
return (unsigned long)site + *site; |
|
} |
|
|
|
static inline int patch_instruction_site(s32 *site, struct ppc_inst instr) |
|
{ |
|
return patch_instruction((struct ppc_inst *)patch_site_addr(site), instr); |
|
} |
|
|
|
static inline int patch_branch_site(s32 *site, unsigned long target, int flags) |
|
{ |
|
return patch_branch((struct ppc_inst *)patch_site_addr(site), target, flags); |
|
} |
|
|
|
static inline int modify_instruction(unsigned int *addr, unsigned int clr, |
|
unsigned int set) |
|
{ |
|
return patch_instruction((struct ppc_inst *)addr, ppc_inst((*addr & ~clr) | set)); |
|
} |
|
|
|
static inline int modify_instruction_site(s32 *site, unsigned int clr, unsigned int set) |
|
{ |
|
return modify_instruction((unsigned int *)patch_site_addr(site), clr, set); |
|
} |
|
|
|
int instr_is_relative_branch(struct ppc_inst instr); |
|
int instr_is_relative_link_branch(struct ppc_inst instr); |
|
int instr_is_branch_to_addr(const struct ppc_inst *instr, unsigned long addr); |
|
unsigned long branch_target(const struct ppc_inst *instr); |
|
int translate_branch(struct ppc_inst *instr, const struct ppc_inst *dest, |
|
const struct ppc_inst *src); |
|
extern bool is_conditional_branch(struct ppc_inst instr); |
|
#ifdef CONFIG_PPC_BOOK3E_64 |
|
void __patch_exception(int exc, unsigned long addr); |
|
#define patch_exception(exc, name) do { \ |
|
extern unsigned int name; \ |
|
__patch_exception((exc), (unsigned long)&name); \ |
|
} while (0) |
|
#endif |
|
|
|
#define OP_RT_RA_MASK 0xffff0000UL |
|
#define LIS_R2 0x3c400000UL |
|
#define ADDIS_R2_R12 0x3c4c0000UL |
|
#define ADDI_R2_R2 0x38420000UL |
|
|
|
static inline unsigned long ppc_function_entry(void *func) |
|
{ |
|
#ifdef PPC64_ELF_ABI_v2 |
|
u32 *insn = func; |
|
|
|
/* |
|
* A PPC64 ABIv2 function may have a local and a global entry |
|
* point. We need to use the local entry point when patching |
|
* functions, so identify and step over the global entry point |
|
* sequence. |
|
* |
|
* The global entry point sequence is always of the form: |
|
* |
|
* addis r2,r12,XXXX |
|
* addi r2,r2,XXXX |
|
* |
|
* A linker optimisation may convert the addis to lis: |
|
* |
|
* lis r2,XXXX |
|
* addi r2,r2,XXXX |
|
*/ |
|
if ((((*insn & OP_RT_RA_MASK) == ADDIS_R2_R12) || |
|
((*insn & OP_RT_RA_MASK) == LIS_R2)) && |
|
((*(insn+1) & OP_RT_RA_MASK) == ADDI_R2_R2)) |
|
return (unsigned long)(insn + 2); |
|
else |
|
return (unsigned long)func; |
|
#elif defined(PPC64_ELF_ABI_v1) |
|
/* |
|
* On PPC64 ABIv1 the function pointer actually points to the |
|
* function's descriptor. The first entry in the descriptor is the |
|
* address of the function text. |
|
*/ |
|
return ((func_descr_t *)func)->entry; |
|
#else |
|
return (unsigned long)func; |
|
#endif |
|
} |
|
|
|
static inline unsigned long ppc_global_function_entry(void *func) |
|
{ |
|
#ifdef PPC64_ELF_ABI_v2 |
|
/* PPC64 ABIv2 the global entry point is at the address */ |
|
return (unsigned long)func; |
|
#else |
|
/* All other cases there is no change vs ppc_function_entry() */ |
|
return ppc_function_entry(func); |
|
#endif |
|
} |
|
|
|
/* |
|
* Wrapper around kallsyms_lookup() to return function entry address: |
|
* - For ABIv1, we lookup the dot variant. |
|
* - For ABIv2, we return the local entry point. |
|
*/ |
|
static inline unsigned long ppc_kallsyms_lookup_name(const char *name) |
|
{ |
|
unsigned long addr; |
|
#ifdef PPC64_ELF_ABI_v1 |
|
/* check for dot variant */ |
|
char dot_name[1 + KSYM_NAME_LEN]; |
|
bool dot_appended = false; |
|
|
|
if (strnlen(name, KSYM_NAME_LEN) >= KSYM_NAME_LEN) |
|
return 0; |
|
|
|
if (name[0] != '.') { |
|
dot_name[0] = '.'; |
|
dot_name[1] = '\0'; |
|
strlcat(dot_name, name, sizeof(dot_name)); |
|
dot_appended = true; |
|
} else { |
|
dot_name[0] = '\0'; |
|
strlcat(dot_name, name, sizeof(dot_name)); |
|
} |
|
addr = kallsyms_lookup_name(dot_name); |
|
if (!addr && dot_appended) |
|
/* Let's try the original non-dot symbol lookup */ |
|
addr = kallsyms_lookup_name(name); |
|
#elif defined(PPC64_ELF_ABI_v2) |
|
addr = kallsyms_lookup_name(name); |
|
if (addr) |
|
addr = ppc_function_entry((void *)addr); |
|
#else |
|
addr = kallsyms_lookup_name(name); |
|
#endif |
|
return addr; |
|
} |
|
|
|
#ifdef CONFIG_PPC64 |
|
/* |
|
* Some instruction encodings commonly used in dynamic ftracing |
|
* and function live patching. |
|
*/ |
|
|
|
/* This must match the definition of STK_GOT in <asm/ppc_asm.h> */ |
|
#ifdef PPC64_ELF_ABI_v2 |
|
#define R2_STACK_OFFSET 24 |
|
#else |
|
#define R2_STACK_OFFSET 40 |
|
#endif |
|
|
|
#define PPC_INST_LD_TOC (PPC_INST_LD | ___PPC_RT(__REG_R2) | \ |
|
___PPC_RA(__REG_R1) | R2_STACK_OFFSET) |
|
|
|
/* usually preceded by a mflr r0 */ |
|
#define PPC_INST_STD_LR (PPC_INST_STD | ___PPC_RS(__REG_R0) | \ |
|
___PPC_RA(__REG_R1) | PPC_LR_STKOFF) |
|
#endif /* CONFIG_PPC64 */ |
|
|
|
#endif /* _ASM_POWERPC_CODE_PATCHING_H */
|
|
|