From f2ce48024a9a6d3e92a023ded0f7b1e99da1cd16 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Sun, 14 Feb 2010 22:56:24 +0000 Subject: [PATCH] Blackfin: simplify PTRACE_{PEEK,POKE}USR in preperation for regset support Signed-off-by: Mike Frysinger --- arch/blackfin/include/asm/ptrace.h | 2 + arch/blackfin/kernel/ptrace.c | 118 +++++++++++++---------------- 2 files changed, 53 insertions(+), 67 deletions(-) diff --git a/arch/blackfin/include/asm/ptrace.h b/arch/blackfin/include/asm/ptrace.h index b33a4488f498..c1aebdb981c7 100644 --- a/arch/blackfin/include/asm/ptrace.h +++ b/arch/blackfin/include/asm/ptrace.h @@ -173,4 +173,6 @@ extern void show_regs(struct pt_regs *); #define PT_FDPIC_EXEC 232 #define PT_FDPIC_INTERP 236 +#define PT_LAST_PSEUDO PT_FDPIC_INTERP + #endif /* _BFIN_PTRACE_H */ diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c index 14118e40f18f..9536c1e2d1c7 100644 --- a/arch/blackfin/kernel/ptrace.c +++ b/arch/blackfin/kernel/ptrace.c @@ -25,7 +25,6 @@ #include #include -#define TEXT_OFFSET 0 /* * does not yet catch signals sent when the child dies. * in exit.c or in signal.c. @@ -43,7 +42,7 @@ * kernel stack will not be empty on entry to the kernel, so * ptracing these tasks will fail. */ -static inline struct pt_regs *get_user_regs(struct task_struct *task) +static inline struct pt_regs *task_pt_regs(struct task_struct *task) { return (struct pt_regs *) ((unsigned long)task_stack_page(task) + @@ -56,7 +55,7 @@ static inline struct pt_regs *get_user_regs(struct task_struct *task) static inline int ptrace_getregs(struct task_struct *tsk, void __user *uregs) { struct pt_regs regs; - memcpy(®s, get_user_regs(tsk), sizeof(regs)); + memcpy(®s, task_pt_regs(tsk), sizeof(regs)); regs.usp = tsk->thread.usp; return copy_to_user(uregs, ®s, sizeof(struct pt_regs)) ? -EFAULT : 0; } @@ -69,40 +68,49 @@ static inline int ptrace_getregs(struct task_struct *tsk, void __user *uregs) /* * Get contents of register REGNO in task TASK. */ -static inline long get_reg(struct task_struct *task, int regno) +static inline long +get_reg(struct task_struct *task, long regno, unsigned long __user *datap) { - unsigned char *reg_ptr; + long tmp; + struct pt_regs *regs = task_pt_regs(task); - struct pt_regs *regs = - (struct pt_regs *)((unsigned long)task_stack_page(task) + - (THREAD_SIZE - sizeof(struct pt_regs))); - reg_ptr = (char *)regs; + if (regno & 3 || regno > PT_LAST_PSEUDO || regno < 0) + return -EIO; switch (regno) { + case PT_TEXT_ADDR: + tmp = task->mm->start_code; + break; + case PT_TEXT_END_ADDR: + tmp = task->mm->end_code; + break; + case PT_DATA_ADDR: + tmp = task->mm->start_data; + break; case PT_USP: - return task->thread.usp; + tmp = task->thread.usp; + break; default: - if (regno <= 216) - return *(long *)(reg_ptr + regno); + if (regno < sizeof(*regs)) { + void *reg_ptr = regs; + tmp = *(long *)(reg_ptr + regno); + } else + return -EIO; } - /* slight mystery ... never seems to come here but kernel misbehaves without this code! */ - printk(KERN_WARNING "Request to get for unknown register %d\n", regno); - return 0; + return put_user(tmp, datap); } /* * Write contents of register REGNO in task TASK. */ static inline int -put_reg(struct task_struct *task, int regno, unsigned long data) +put_reg(struct task_struct *task, long regno, unsigned long data) { - char *reg_ptr; + struct pt_regs *regs = task_pt_regs(task); - struct pt_regs *regs = - (struct pt_regs *)((unsigned long)task_stack_page(task) + - (THREAD_SIZE - sizeof(struct pt_regs))); - reg_ptr = (char *)regs; + if (regno & 3 || regno > PT_LAST_PSEUDO || regno < 0) + return -EIO; switch (regno) { case PT_PC: @@ -119,10 +127,18 @@ put_reg(struct task_struct *task, int regno, unsigned long data) regs->usp = data; task->thread.usp = data; break; + case PT_SYSCFG: /* don't let userspace screw with this */ + if ((data & ~1) != 0x6) + pr_warning("ptrace: ignore syscfg write of %#lx\n", data); + break; /* regs->syscfg = data; break; */ default: - if (regno <= 216) - *(long *)(reg_ptr + regno) = data; + if (regno < sizeof(*regs)) { + void *reg_offset = regs; + *(long *)(reg_offset + regno) = data; + } + /* Ignore writes to pseudo registers */ } + return 0; } @@ -231,40 +247,6 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) break; } - /* read the word at location addr in the USER area. */ - case PTRACE_PEEKUSR: - { - unsigned long tmp; - ret = -EIO; - tmp = 0; - if ((addr & 3) || (addr > (sizeof(struct pt_regs) + 16))) { - printk(KERN_WARNING "ptrace error : PEEKUSR : temporarily returning " - "0 - %x sizeof(pt_regs) is %lx\n", - (int)addr, sizeof(struct pt_regs)); - break; - } - if (addr == sizeof(struct pt_regs)) { - /* PT_TEXT_ADDR */ - tmp = child->mm->start_code + TEXT_OFFSET; - } else if (addr == (sizeof(struct pt_regs) + 4)) { - /* PT_TEXT_END_ADDR */ - tmp = child->mm->end_code; - } else if (addr == (sizeof(struct pt_regs) + 8)) { - /* PT_DATA_ADDR */ - tmp = child->mm->start_data; -#ifdef CONFIG_BINFMT_ELF_FDPIC - } else if (addr == (sizeof(struct pt_regs) + 12)) { - goto case_PTRACE_GETFDPIC_EXEC; - } else if (addr == (sizeof(struct pt_regs) + 16)) { - goto case_PTRACE_GETFDPIC_INTERP; -#endif - } else { - tmp = get_reg(child, addr); - } - ret = put_user(tmp, datap); - break; - } - #ifdef CONFIG_BINFMT_ELF_FDPIC case PTRACE_GETFDPIC: { unsigned long tmp = 0; @@ -327,19 +309,21 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) break; } - case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ - ret = -EIO; - if ((addr & 3) || (addr > (sizeof(struct pt_regs) + 16))) { - printk(KERN_WARNING "ptrace error : POKEUSR: temporarily returning 0\n"); - break; + case PTRACE_PEEKUSR: + switch (addr) { +#ifdef CONFIG_BINFMT_ELF_FDPIC /* backwards compat */ + case PT_FDPIC_EXEC: goto case_PTRACE_GETFDPIC_EXEC; + case PT_FDPIC_INTERP: goto case_PTRACE_GETFDPIC_INTERP; +#endif + default: + ret = get_reg(child, addr, datap); } + pr_debug("ptrace: PEEKUSR reg %li with %#lx = %i\n", addr, data, ret); + break; - /* Ignore writes to SYSCFG and other pseudo regs */ - if (addr >= PT_SYSCFG) { - ret = 0; - break; - } + case PTRACE_POKEUSR: ret = put_reg(child, addr, data); + pr_debug("ptrace: POKEUSR reg %li with %li = %i\n", addr, data, ret); break; case PTRACE_GETREGS: