diff options
Diffstat (limited to 'arch/powerpc/include/asm/code-patching.h')
| -rw-r--r-- | arch/powerpc/include/asm/code-patching.h | 133 |
1 files changed, 91 insertions, 42 deletions
diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h index 898b54262881..0e29ccf903d0 100644 --- a/arch/powerpc/include/asm/code-patching.h +++ b/arch/powerpc/include/asm/code-patching.h @@ -11,6 +11,7 @@ #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); @@ -21,34 +22,79 @@ #define BRANCH_SET_LINK 0x1 #define BRANCH_ABSOLUTE 0x2 -bool is_offset_in_branch_range(long offset); -unsigned int create_branch(const unsigned int *addr, - unsigned long target, int flags); -unsigned int create_cond_branch(const unsigned int *addr, - unsigned long target, int flags); -int patch_branch(unsigned int *addr, unsigned long target, int flags); -int patch_instruction(unsigned int *addr, unsigned int instr); -int raw_patch_instruction(unsigned int *addr, unsigned int instr); +/* + * 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, unsigned int instr) +static inline int patch_instruction_site(s32 *site, ppc_inst_t instr) { - return patch_instruction((unsigned int *)patch_site_addr(site), 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((unsigned int *)patch_site_addr(site), target, 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, (*addr & ~clr) | set); + return patch_instruction(addr, ppc_inst((*addr & ~clr) | set)); } static inline int modify_instruction_site(s32 *site, unsigned int clr, unsigned int set) @@ -56,29 +102,36 @@ static inline int modify_instruction_site(s32 *site, unsigned int clr, unsigned return modify_instruction((unsigned int *)patch_site_addr(site), clr, set); } -int instr_is_relative_branch(unsigned int instr); -int instr_is_relative_link_branch(unsigned int instr); -int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr); -unsigned long branch_target(const unsigned int *instr); -unsigned int translate_branch(const unsigned int *dest, - const unsigned int *src); -extern bool is_conditional_branch(unsigned int 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 +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 0x3c020000UL -#define ADDIS_R2_R12 0x3c4c0000UL -#define ADDI_R2_R2 0x38420000UL +#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 PPC64_ELF_ABI_v2 +#ifdef CONFIG_PPC64_ELF_ABI_V2 u32 *insn = func; /* @@ -103,13 +156,13 @@ static inline unsigned long ppc_function_entry(void *func) return (unsigned long)(insn + 2); else return (unsigned long)func; -#elif defined(PPC64_ELF_ABI_v1) +#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 ((func_descr_t *)func)->entry; + return ((struct func_desc *)func)->addr; #else return (unsigned long)func; #endif @@ -117,7 +170,7 @@ static inline unsigned long ppc_function_entry(void *func) static inline unsigned long ppc_global_function_entry(void *func) { -#ifdef PPC64_ELF_ABI_v2 +#ifdef CONFIG_PPC64_ELF_ABI_V2 /* PPC64 ABIv2 the global entry point is at the address */ return (unsigned long)func; #else @@ -134,7 +187,7 @@ static inline unsigned long ppc_global_function_entry(void *func) static inline unsigned long ppc_kallsyms_lookup_name(const char *name) { unsigned long addr; -#ifdef PPC64_ELF_ABI_v1 +#ifdef CONFIG_PPC64_ELF_ABI_V1 /* check for dot variant */ char dot_name[1 + KSYM_NAME_LEN]; bool dot_appended = false; @@ -155,7 +208,7 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *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) +#elif defined(CONFIG_PPC64_ELF_ABI_V2) addr = kallsyms_lookup_name(name); if (addr) addr = ppc_function_entry((void *)addr); @@ -165,25 +218,21 @@ static inline unsigned long ppc_kallsyms_lookup_name(const char *name) 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 +#ifdef CONFIG_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) +#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_INST_STD | ___PPC_RS(__REG_R0) | \ - ___PPC_RA(__REG_R1) | PPC_LR_STKOFF) -#endif /* CONFIG_PPC64 */ +#define PPC_INST_STD_LR PPC_RAW_STD(_R0, _R1, PPC_LR_STKOFF) #endif /* _ASM_POWERPC_CODE_PATCHING_H */ |