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Diffstat (limited to 'arch/powerpc/include/asm/code-patching.h')
| -rw-r--r-- | arch/powerpc/include/asm/code-patching.h | 238 |
1 files changed, 0 insertions, 238 deletions
diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h deleted file mode 100644 index 0e29ccf903d0..000000000000 --- a/arch/powerpc/include/asm/code-patching.h +++ /dev/null @@ -1,238 +0,0 @@ -/* 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 - -/* - * 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 - */ -static inline bool is_offset_in_branch_range(long offset) -{ - return (offset >= -0x2000000 && offset <= 0x1fffffc && !(offset & 0x3)); -} - -static inline bool is_offset_in_cond_branch_range(long offset) -{ - return offset >= -0x8000 && offset <= 0x7fff && !(offset & 0x3); -} - -static inline int create_branch(ppc_inst_t *instr, const u32 *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(ppc_inst_t *instr, const u32 *addr, - unsigned long target, int flags); -int patch_branch(u32 *addr, unsigned long target, int flags); -int patch_instruction(u32 *addr, ppc_inst_t instr); -int raw_patch_instruction(u32 *addr, ppc_inst_t instr); -int patch_instructions(u32 *addr, u32 *code, size_t len, bool repeat_instr); - -static inline unsigned long patch_site_addr(s32 *site) -{ - return (unsigned long)site + *site; -} - -static inline int patch_instruction_site(s32 *site, ppc_inst_t instr) -{ - return patch_instruction((u32 *)patch_site_addr(site), instr); -} - -static inline int patch_branch_site(s32 *site, unsigned long target, int flags) -{ - return patch_branch((u32 *)patch_site_addr(site), target, flags); -} - -static inline int modify_instruction(unsigned int *addr, unsigned int clr, - unsigned int set) -{ - return patch_instruction(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); -} - -static inline unsigned int branch_opcode(ppc_inst_t instr) -{ - return ppc_inst_primary_opcode(instr) & 0x3F; -} - -static inline int instr_is_branch_iform(ppc_inst_t instr) -{ - return branch_opcode(instr) == 18; -} - -static inline int instr_is_branch_bform(ppc_inst_t instr) -{ - return branch_opcode(instr) == 16; -} - -int instr_is_relative_branch(ppc_inst_t instr); -int instr_is_relative_link_branch(ppc_inst_t instr); -unsigned long branch_target(const u32 *instr); -int translate_branch(ppc_inst_t *instr, const u32 *dest, const u32 *src); -bool is_conditional_branch(ppc_inst_t instr); - -#define OP_RT_RA_MASK 0xffff0000UL -#define LIS_R2 (PPC_RAW_LIS(_R2, 0)) -#define ADDIS_R2_R12 (PPC_RAW_ADDIS(_R2, _R12, 0)) -#define ADDI_R2_R2 (PPC_RAW_ADDI(_R2, _R2, 0)) - - -static inline unsigned long ppc_function_entry(void *func) -{ -#ifdef CONFIG_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(CONFIG_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 ((struct func_desc *)func)->addr; -#else - return (unsigned long)func; -#endif -} - -static inline unsigned long ppc_global_function_entry(void *func) -{ -#ifdef CONFIG_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 CONFIG_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(CONFIG_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; -} - -/* - * 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 CONFIG_PPC64_ELF_ABI_V2 -#define R2_STACK_OFFSET 24 -#else -#define R2_STACK_OFFSET 40 -#endif - -#define PPC_INST_LD_TOC PPC_RAW_LD(_R2, _R1, R2_STACK_OFFSET) - -/* usually preceded by a mflr r0 */ -#define PPC_INST_STD_LR PPC_RAW_STD(_R0, _R1, PPC_LR_STKOFF) - -#endif /* _ASM_POWERPC_CODE_PATCHING_H */ |