From 9d3918f7c0e516bb8782915cdb2f8cbdbf6c4f9b Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Thu, 28 Jul 2016 10:57:39 +0800 Subject: [PATCH] powerpc/ptrace: Enable support for NT_PPC_CVSX This patch enables support for TM checkpointed VSX register set ELF core note NT_PPC_CVSX based ptrace requests through PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved through adding a register set REGSET_CVSX 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 | 129 ++++++++++++++++++++++++++++ 2 files changed, 130 insertions(+) diff --git a/arch/powerpc/include/uapi/asm/elf.h b/arch/powerpc/include/uapi/asm/elf.h index ecb4e84cb22c..1549172aa258 100644 --- a/arch/powerpc/include/uapi/asm/elf.h +++ b/arch/powerpc/include/uapi/asm/elf.h @@ -92,6 +92,7 @@ #define ELF_NGREG 48 /* includes nip, msr, lr, etc. */ #define ELF_NFPREG 33 /* includes fpscr */ #define ELF_NVMX 34 /* includes all vector registers */ +#define ELF_NVSX 32 /* includes all VSX registers */ 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 6e42137c0175..df6afe7da4da 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -65,6 +65,7 @@ struct pt_regs_offset { #define REG_OFFSET_END {.name = NULL, .offset = 0} #define TVSO(f) (offsetof(struct thread_vr_state, f)) +#define TFSO(f) (offsetof(struct thread_fp_state, f)) static const struct pt_regs_offset regoffset_table[] = { GPR_OFFSET_NAME(0), @@ -1294,6 +1295,123 @@ static int tm_cvmx_set(struct task_struct *target, return ret; } + +/** + * tm_cvsx_active - get active number of registers in CVSX + * @target: The target task. + * @regset: The user regset structure. + * + * This function checks for the active number of available + * regisers in transaction checkpointed VSX category. + */ +static int tm_cvsx_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; + + flush_vsx_to_thread(target); + return target->thread.used_vsr ? regset->n : 0; +} + +/** + * tm_cvsx_get - get CVSX 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 in transaction checkpointed VSX registers. + * + * When the transaction is active 'fp_state' holds the checkpointed + * values for the current transaction to fall back on if it aborts + * in between. This function gets those checkpointed VSX registers. + * The userspace interface buffer layout is as follows. + * + * struct data { + * u64 vsx[32]; + *}; + */ +static int tm_cvsx_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + u64 buf[32]; + int ret, i; + + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + if (!MSR_TM_ACTIVE(target->thread.regs->msr)) + return -ENODATA; + + /* Flush the state */ + flush_fp_to_thread(target); + flush_altivec_to_thread(target); + flush_tmregs_to_thread(target); + flush_vsx_to_thread(target); + + for (i = 0; i < 32 ; i++) + buf[i] = target->thread.fp_state.fpr[i][TS_VSRLOWOFFSET]; + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + buf, 0, 32 * sizeof(double)); + + return ret; +} + +/** + * tm_cvsx_set - set CFPR 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 VSX registers. + * + * When the transaction is active 'fp_state' holds the checkpointed + * VSX register values for the current transaction to fall back on + * if it aborts in between. This function sets these checkpointed + * FPR registers. The userspace interface buffer layout is as follows. + * + * struct data { + * u64 vsx[32]; + *}; + */ +static int tm_cvsx_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + u64 buf[32]; + int ret, i; + + if (!cpu_has_feature(CPU_FTR_TM)) + return -ENODEV; + + if (!MSR_TM_ACTIVE(target->thread.regs->msr)) + return -ENODATA; + + /* Flush the state */ + flush_fp_to_thread(target); + flush_altivec_to_thread(target); + flush_tmregs_to_thread(target); + flush_vsx_to_thread(target); + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + buf, 0, 32 * sizeof(double)); + for (i = 0; i < 32 ; i++) + target->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i]; + + return ret; +} #endif /* @@ -1315,6 +1433,7 @@ enum powerpc_regset { REGSET_TM_CGPR, /* TM checkpointed GPR registers */ REGSET_TM_CFPR, /* TM checkpointed FPR registers */ REGSET_TM_CVMX, /* TM checkpointed VMX registers */ + REGSET_TM_CVSX, /* TM checkpointed VSX registers */ #endif }; @@ -1366,6 +1485,11 @@ static const struct user_regset native_regsets[] = { .size = sizeof(vector128), .align = sizeof(vector128), .active = tm_cvmx_active, .get = tm_cvmx_get, .set = tm_cvmx_set }, + [REGSET_TM_CVSX] = { + .core_note_type = NT_PPC_TM_CVSX, .n = ELF_NVSX, + .size = sizeof(double), .align = sizeof(double), + .active = tm_cvsx_active, .get = tm_cvsx_get, .set = tm_cvsx_set + }, #endif }; @@ -1608,6 +1732,11 @@ static const struct user_regset compat_regsets[] = { .size = sizeof(vector128), .align = sizeof(vector128), .active = tm_cvmx_active, .get = tm_cvmx_get, .set = tm_cvmx_set }, + [REGSET_TM_CVSX] = { + .core_note_type = NT_PPC_TM_CVSX, .n = ELF_NVSX, + .size = sizeof(double), .align = sizeof(double), + .active = tm_cvsx_active, .get = tm_cvsx_get, .set = tm_cvsx_set + }, #endif }; -- 2.20.1