From 08e1c01d6aedf00af04d9571a0a5d5867298b719 Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Thu, 28 Jul 2016 10:57:40 +0800 Subject: [PATCH] powerpc/ptrace: Enable support for TM SPR state This patch enables support for TM SPR state related ELF core note NT_PPC_TM_SPR based ptrace requests through PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved through adding a register set REGSET_TM_SPR in powerpc corresponding to the ELF core note section added. It implements the get, set and active functions for this new register set added. Signed-off-by: Anshuman Khandual Signed-off-by: Simon Guo Signed-off-by: Michael Ellerman --- arch/powerpc/include/uapi/asm/elf.h | 1 + arch/powerpc/kernel/ptrace.c | 143 +++++++++++++++++++++++++++- 2 files changed, 143 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/uapi/asm/elf.h b/arch/powerpc/include/uapi/asm/elf.h index 1549172aa258..e703c646163b 100644 --- a/arch/powerpc/include/uapi/asm/elf.h +++ b/arch/powerpc/include/uapi/asm/elf.h @@ -93,6 +93,7 @@ #define ELF_NFPREG 33 /* includes fpscr */ #define ELF_NVMX 34 /* includes all vector registers */ #define ELF_NVSX 32 /* includes all VSX registers */ +#define ELF_NTMSPRREG 3 /* include tfhar, tfiar, texasr */ typedef unsigned long elf_greg_t64; typedef elf_greg_t64 elf_gregset_t64[ELF_NGREG]; diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index df6afe7da4da..f654224d2653 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -66,6 +66,7 @@ struct pt_regs_offset { #define TVSO(f) (offsetof(struct thread_vr_state, f)) #define TFSO(f) (offsetof(struct thread_fp_state, f)) +#define TSO(f) (offsetof(struct thread_struct, f)) static const struct pt_regs_offset regoffset_table[] = { GPR_OFFSET_NAME(0), @@ -1412,7 +1413,136 @@ static int tm_cvsx_set(struct task_struct *target, return ret; } -#endif + +/** + * tm_spr_active - get active number of registers in TM SPR + * @target: The target task. + * @regset: The user regset structure. + * + * This function checks the active number of available + * regisers in the transactional memory SPR category. + */ +static int tm_spr_active(struct task_struct *target, + const struct user_regset *regset) +{ + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + return regset->n; +} + +/** + * tm_spr_get - get the TM related SPR registers + * @target: The target task. + * @regset: The user regset structure. + * @pos: The buffer position. + * @count: Number of bytes to copy. + * @kbuf: Kernel buffer to copy from. + * @ubuf: User buffer to copy into. + * + * This function gets transactional memory related SPR registers. + * The userspace interface buffer layout is as follows. + * + * struct { + * u64 tm_tfhar; + * u64 tm_texasr; + * u64 tm_tfiar; + * }; + */ +static int tm_spr_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + int ret; + + /* Build tests */ + BUILD_BUG_ON(TSO(tm_tfhar) + sizeof(u64) != TSO(tm_texasr)); + BUILD_BUG_ON(TSO(tm_texasr) + sizeof(u64) != TSO(tm_tfiar)); + BUILD_BUG_ON(TSO(tm_tfiar) + sizeof(u64) != TSO(ckpt_regs)); + + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + /* Flush the states */ + flush_fp_to_thread(target); + flush_altivec_to_thread(target); + flush_tmregs_to_thread(target); + + /* TFHAR register */ + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.tm_tfhar, 0, sizeof(u64)); + + /* TEXASR register */ + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.tm_texasr, sizeof(u64), + 2 * sizeof(u64)); + + /* TFIAR register */ + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.tm_tfiar, + 2 * sizeof(u64), 3 * sizeof(u64)); + return ret; +} + +/** + * tm_spr_set - set the TM related SPR registers + * @target: The target task. + * @regset: The user regset structure. + * @pos: The buffer position. + * @count: Number of bytes to copy. + * @kbuf: Kernel buffer to copy into. + * @ubuf: User buffer to copy from. + * + * This function sets transactional memory related SPR registers. + * The userspace interface buffer layout is as follows. + * + * struct { + * u64 tm_tfhar; + * u64 tm_texasr; + * u64 tm_tfiar; + * }; + */ +static int tm_spr_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + + /* Build tests */ + BUILD_BUG_ON(TSO(tm_tfhar) + sizeof(u64) != TSO(tm_texasr)); + BUILD_BUG_ON(TSO(tm_texasr) + sizeof(u64) != TSO(tm_tfiar)); + BUILD_BUG_ON(TSO(tm_tfiar) + sizeof(u64) != TSO(ckpt_regs)); + + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + /* Flush the states */ + flush_fp_to_thread(target); + flush_altivec_to_thread(target); + flush_tmregs_to_thread(target); + + /* TFHAR register */ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.tm_tfhar, 0, sizeof(u64)); + + /* TEXASR register */ + if (!ret) + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.tm_texasr, sizeof(u64), + 2 * sizeof(u64)); + + /* TFIAR register */ + if (!ret) + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.tm_tfiar, + 2 * sizeof(u64), 3 * sizeof(u64)); + return ret; +} +#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ /* * These are our native regset flavors. @@ -1434,6 +1564,7 @@ enum powerpc_regset { REGSET_TM_CFPR, /* TM checkpointed FPR registers */ REGSET_TM_CVMX, /* TM checkpointed VMX registers */ REGSET_TM_CVSX, /* TM checkpointed VSX registers */ + REGSET_TM_SPR, /* TM specific SPR registers */ #endif }; @@ -1490,6 +1621,11 @@ static const struct user_regset native_regsets[] = { .size = sizeof(double), .align = sizeof(double), .active = tm_cvsx_active, .get = tm_cvsx_get, .set = tm_cvsx_set }, + [REGSET_TM_SPR] = { + .core_note_type = NT_PPC_TM_SPR, .n = ELF_NTMSPRREG, + .size = sizeof(u64), .align = sizeof(u64), + .active = tm_spr_active, .get = tm_spr_get, .set = tm_spr_set + }, #endif }; @@ -1737,6 +1873,11 @@ static const struct user_regset compat_regsets[] = { .size = sizeof(double), .align = sizeof(double), .active = tm_cvsx_active, .get = tm_cvsx_get, .set = tm_cvsx_set }, + [REGSET_TM_SPR] = { + .core_note_type = NT_PPC_TM_SPR, .n = ELF_NTMSPRREG, + .size = sizeof(u64), .align = sizeof(u64), + .active = tm_spr_active, .get = tm_spr_get, .set = tm_spr_set + }, #endif };