Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754786AbbDTUVr (ORCPT ); Mon, 20 Apr 2015 16:21:47 -0400 Received: from mail-qg0-f53.google.com ([209.85.192.53]:36455 "EHLO mail-qg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753750AbbDTUTw (ORCPT ); Mon, 20 Apr 2015 16:19:52 -0400 From: David Long To: linux-arm-kernel@lists.infradead.org, Russell King Cc: sandeepa.s.prabhu@gmail.com, William Cohen , Steve Capper , Catalin Marinas , Will Deacon , "Jon Medhurst (Tixy)" , Masami Hiramatsu , Ananth N Mavinakayanahalli , Anil S Keshavamurthy , , linux-kernel@vger.kernel.org Subject: [PATCH v6 1/6] arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature Date: Mon, 20 Apr 2015 16:19:42 -0400 Message-Id: <1429561187-3661-2-git-send-email-dave.long@linaro.org> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1429561187-3661-1-git-send-email-dave.long@linaro.org> References: <1429561187-3661-1-git-send-email-dave.long@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7529 Lines: 258 From: "David A. Long" Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64. Signed-off-by: David A. Long --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/ptrace.h | 29 +++++++++ arch/arm64/include/uapi/asm/ptrace.h | 36 +++++++++++ arch/arm64/kernel/ptrace.c | 116 +++++++++++++++++++++++++++++++++++ 4 files changed, 182 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1b8e973..987a681 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -65,6 +65,7 @@ config ARM64 select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RCU_TABLE_FREE select HAVE_SYSCALL_TRACEPOINTS select IRQ_DOMAIN diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index d6dd9fd..655620e 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -118,6 +118,8 @@ struct pt_regs { u64 syscallno; }; +#define MAX_REG_OFFSET (sizeof(struct user_pt_regs) - sizeof(u64)) + #define arch_has_single_step() (1) #ifdef CONFIG_COMPAT @@ -146,11 +148,38 @@ struct pt_regs { #define user_stack_pointer(regs) \ (!compat_user_mode(regs) ? (regs)->sp : (regs)->compat_sp) +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset number of the register. + * + * regs_get_register returns the value of a register whose offset from @regs. + * The @offset is the offset of the register in struct pt_regs. + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. + */ +static inline u64 regs_get_register(struct pt_regs *regs, + unsigned int offset) +{ + if (unlikely(offset > MAX_REG_OFFSET)) + return 0; + return *(u64 *)((u64)regs + offset); +} + +/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->ARM_sp; +} + static inline unsigned long regs_return_value(struct pt_regs *regs) { return regs->regs[0]; } +extern int regs_query_register_offset(const char *name); +extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, + unsigned int n); + /* * Are the current registers suitable for user mode? (used to maintain * security in signal handlers) diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h index 6913643..58c0223 100644 --- a/arch/arm64/include/uapi/asm/ptrace.h +++ b/arch/arm64/include/uapi/asm/ptrace.h @@ -61,6 +61,42 @@ #ifndef __ASSEMBLY__ +#define ARM_pstate pstate +#define ARM_pc pc +#define ARM_sp sp +#define ARM_lr regs[30] +#define ARM_fp regs[29] +#define ARM_x28 regs[28] +#define ARM_x27 regs[27] +#define ARM_x26 regs[26] +#define ARM_x25 regs[25] +#define ARM_x24 regs[24] +#define ARM_x23 regs[23] +#define ARM_x22 regs[22] +#define ARM_x21 regs[21] +#define ARM_x20 regs[20] +#define ARM_x19 regs[19] +#define ARM_x18 regs[18] +#define ARM_ip1 regs[17] +#define ARM_ip0 regs[16] +#define ARM_x15 regs[15] +#define ARM_x14 regs[14] +#define ARM_x13 regs[13] +#define ARM_x12 regs[12] +#define ARM_x11 regs[11] +#define ARM_x10 regs[10] +#define ARM_x9 regs[9] +#define ARM_x8 regs[8] +#define ARM_x7 regs[7] +#define ARM_x6 regs[6] +#define ARM_x5 regs[5] +#define ARM_x4 regs[4] +#define ARM_x3 regs[3] +#define ARM_x2 regs[2] +#define ARM_x1 regs[1] +#define ARM_x0 regs[0] +#define ARM_ORIG_x0 orig_x0 + /* * User structures for general purpose, floating point and debug registers. */ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index d882b83..a889f79 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -48,6 +48,122 @@ #define CREATE_TRACE_POINTS #include +struct pt_regs_offset { + const char *name; + int offset; +}; + +#define REG_OFFSET_NAME(r) \ + {.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)} +#define REG_OFFSET_END {.name = NULL, .offset = 0} + +static const struct pt_regs_offset regoffset_table[] = { + REG_OFFSET_NAME(x0), + REG_OFFSET_NAME(x1), + REG_OFFSET_NAME(x2), + REG_OFFSET_NAME(x3), + REG_OFFSET_NAME(x4), + REG_OFFSET_NAME(x5), + REG_OFFSET_NAME(x6), + REG_OFFSET_NAME(x7), + REG_OFFSET_NAME(x8), + REG_OFFSET_NAME(x9), + REG_OFFSET_NAME(x10), + REG_OFFSET_NAME(x11), + REG_OFFSET_NAME(x12), + REG_OFFSET_NAME(x13), + REG_OFFSET_NAME(x14), + REG_OFFSET_NAME(x15), + REG_OFFSET_NAME(ip0), + REG_OFFSET_NAME(ip1), + REG_OFFSET_NAME(x18), + REG_OFFSET_NAME(x19), + REG_OFFSET_NAME(x20), + REG_OFFSET_NAME(x21), + REG_OFFSET_NAME(x22), + REG_OFFSET_NAME(x23), + REG_OFFSET_NAME(x24), + REG_OFFSET_NAME(x25), + REG_OFFSET_NAME(x26), + REG_OFFSET_NAME(x27), + REG_OFFSET_NAME(x28), + REG_OFFSET_NAME(fp), + REG_OFFSET_NAME(lr), + REG_OFFSET_NAME(sp), + REG_OFFSET_NAME(pc), + REG_OFFSET_NAME(pstate), + REG_OFFSET_NAME(ORIG_x0), + REG_OFFSET_END, +}; + +/** + * regs_query_register_offset() - query register offset from its name + * @name: the name of a register + * + * regs_query_register_offset() returns the offset of a register in struct + * pt_regs from its name. If the name is invalid, this returns -EINVAL; + */ +int regs_query_register_offset(const char *name) +{ + const struct pt_regs_offset *roff; + + for (roff = regoffset_table; roff->name != NULL; roff++) + if (!strcmp(roff->name, name)) + return roff->offset; + return -EINVAL; +} + +/** + * regs_query_register_name() - query register name from its offset + * @offset: the offset of a register in struct pt_regs. + * + * regs_query_register_name() returns the name of a register from its + * offset in struct pt_regs. If the @offset is invalid, this returns NULL; + */ +const char *regs_query_register_name(unsigned int offset) +{ + const struct pt_regs_offset *roff; + + for (roff = regoffset_table; roff->name != NULL; roff++) + if (roff->offset == offset) + return roff->name; + return NULL; +} + +/** + * regs_within_kernel_stack() - check the address in the stack + * @regs: pt_regs which contains kernel stack pointer. + * @addr: address which is checked. + * + * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). + * If @addr is within the kernel stack, it returns true. If not, returns false. + */ +bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) +{ + return ((addr & ~(THREAD_SIZE - 1)) == + (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))); +} + +/** + * regs_get_kernel_stack_nth() - get Nth entry of the stack + * @regs: pt_regs which contains kernel stack pointer. + * @n: stack entry number. + * + * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which + * is specified by @regs. If the @n th entry is NOT in the kernel stack, + * this returns 0. + */ +unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); + + addr += n; + if (regs_within_kernel_stack(regs, (unsigned long)addr)) + return *addr; + else + return 0; +} + /* * TODO: does not yet catch signals sent when the child dies. * in exit.c or in signal.c. -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/