From: Anshuman Khandual Date: Thu, 28 Jul 2016 02:57:36 +0000 (+0800) Subject: powerpc/ptrace: Enable support for NT_PPC_CGPR X-Git-Tag: v4.8-rc1~30^2~11 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=25847fb195ae09ba28896184d361acc73aaa2fb1;p=linux.git powerpc/ptrace: Enable support for NT_PPC_CGPR This patch enables support for TM checkpointed GPR register set ELF core note NT_PPC_CGPR based ptrace requests through PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved through adding a register set REGSET_CGPR 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 --- diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 83cd0a18fec9..ce853c72fc74 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -181,6 +181,26 @@ static int set_user_msr(struct task_struct *task, unsigned long msr) return 0; } +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +static unsigned long get_user_ckpt_msr(struct task_struct *task) +{ + return task->thread.ckpt_regs.msr | task->thread.fpexc_mode; +} + +static int set_user_ckpt_msr(struct task_struct *task, unsigned long msr) +{ + task->thread.ckpt_regs.msr &= ~MSR_DEBUGCHANGE; + task->thread.ckpt_regs.msr |= msr & MSR_DEBUGCHANGE; + return 0; +} + +static int set_user_ckpt_trap(struct task_struct *task, unsigned long trap) +{ + task->thread.ckpt_regs.trap = trap & 0xfff0; + return 0; +} +#endif + #ifdef CONFIG_PPC64 static int get_user_dscr(struct task_struct *task, unsigned long *data) { @@ -847,6 +867,172 @@ static int evr_set(struct task_struct *target, const struct user_regset *regset, } #endif /* CONFIG_SPE */ +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +/** + * tm_cgpr_active - get active number of registers in CGPR + * @target: The target task. + * @regset: The user regset structure. + * + * This function checks for the active number of available + * regisers in transaction checkpointed GPR category. + */ +static int tm_cgpr_active(struct task_struct *target, + const struct user_regset *regset) +{ + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + if (!MSR_TM_ACTIVE(target->thread.regs->msr)) + return 0; + + return regset->n; +} + +/** + * tm_cgpr_get - get CGPR 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 transaction checkpointed GPR registers. + * + * When the transaction is active, 'ckpt_regs' holds all the checkpointed + * GPR register values for the current transaction to fall back on if it + * aborts in between. This function gets those checkpointed GPR registers. + * The userspace interface buffer layout is as follows. + * + * struct data { + * struct pt_regs ckpt_regs; + * }; + */ +static int tm_cgpr_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + int ret; + + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + if (!MSR_TM_ACTIVE(target->thread.regs->msr)) + return -ENODATA; + + flush_fp_to_thread(target); + flush_altivec_to_thread(target); + flush_tmregs_to_thread(target); + + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.ckpt_regs, + 0, offsetof(struct pt_regs, msr)); + if (!ret) { + unsigned long msr = get_user_ckpt_msr(target); + + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &msr, + offsetof(struct pt_regs, msr), + offsetof(struct pt_regs, msr) + + sizeof(msr)); + } + + BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) != + offsetof(struct pt_regs, msr) + sizeof(long)); + + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread.ckpt_regs.orig_gpr3, + offsetof(struct pt_regs, orig_gpr3), + sizeof(struct pt_regs)); + if (!ret) + ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, + sizeof(struct pt_regs), -1); + + return ret; +} + +/* + * tm_cgpr_set - set the CGPR 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 in transaction checkpointed GPR registers. + * + * When the transaction is active, 'ckpt_regs' holds the checkpointed + * GPR register values for the current transaction to fall back on if it + * aborts in between. This function sets those checkpointed GPR registers. + * The userspace interface buffer layout is as follows. + * + * struct data { + * struct pt_regs ckpt_regs; + * }; + */ +static int tm_cgpr_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + unsigned long reg; + int ret; + + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + if (!MSR_TM_ACTIVE(target->thread.regs->msr)) + return -ENODATA; + + flush_fp_to_thread(target); + flush_altivec_to_thread(target); + flush_tmregs_to_thread(target); + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.ckpt_regs, + 0, PT_MSR * sizeof(reg)); + + if (!ret && count > 0) { + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, ®, + PT_MSR * sizeof(reg), + (PT_MSR + 1) * sizeof(reg)); + if (!ret) + ret = set_user_ckpt_msr(target, reg); + } + + BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) != + offsetof(struct pt_regs, msr) + sizeof(long)); + + if (!ret) + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread.ckpt_regs.orig_gpr3, + PT_ORIG_R3 * sizeof(reg), + (PT_MAX_PUT_REG + 1) * sizeof(reg)); + + if (PT_MAX_PUT_REG + 1 < PT_TRAP && !ret) + ret = user_regset_copyin_ignore( + &pos, &count, &kbuf, &ubuf, + (PT_MAX_PUT_REG + 1) * sizeof(reg), + PT_TRAP * sizeof(reg)); + + if (!ret && count > 0) { + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, ®, + PT_TRAP * sizeof(reg), + (PT_TRAP + 1) * sizeof(reg)); + if (!ret) + ret = set_user_ckpt_trap(target, reg); + } + + if (!ret) + ret = user_regset_copyin_ignore( + &pos, &count, &kbuf, &ubuf, + (PT_TRAP + 1) * sizeof(reg), -1); + + return ret; +} +#endif /* * These are our native regset flavors. @@ -863,6 +1049,9 @@ enum powerpc_regset { #ifdef CONFIG_SPE REGSET_SPE, #endif +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + REGSET_TM_CGPR, /* TM checkpointed GPR registers */ +#endif }; static const struct user_regset native_regsets[] = { @@ -897,6 +1086,13 @@ static const struct user_regset native_regsets[] = { .active = evr_active, .get = evr_get, .set = evr_set }, #endif +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + [REGSET_TM_CGPR] = { + .core_note_type = NT_PPC_TM_CGPR, .n = ELF_NGREG, + .size = sizeof(long), .align = sizeof(long), + .active = tm_cgpr_active, .get = tm_cgpr_get, .set = tm_cgpr_set + }, +#endif }; static const struct user_regset_view user_ppc_native_view = { @@ -1059,6 +1255,24 @@ static int gpr32_set_common(struct task_struct *target, (PT_TRAP + 1) * sizeof(reg), -1); } +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM +static int tm_cgpr32_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + return gpr32_get_common(target, regset, pos, count, kbuf, ubuf, 1); +} + +static int tm_cgpr32_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + return gpr32_set_common(target, regset, pos, count, kbuf, ubuf, 1); +} +#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ + static int gpr32_get(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, @@ -1103,6 +1317,14 @@ static const struct user_regset compat_regsets[] = { .active = evr_active, .get = evr_get, .set = evr_set }, #endif +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + [REGSET_TM_CGPR] = { + .core_note_type = NT_PPC_TM_CGPR, .n = ELF_NGREG, + .size = sizeof(long), .align = sizeof(long), + .active = tm_cgpr_active, + .get = tm_cgpr32_get, .set = tm_cgpr32_set + }, +#endif }; static const struct user_regset_view user_ppc_compat_view = {