diff options
Diffstat (limited to 'arch/blackfin/kernel/ptrace.c')
-rw-r--r-- | arch/blackfin/kernel/ptrace.c | 389 |
1 files changed, 172 insertions, 217 deletions
diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c index 65567dc..6ec7768 100644 --- a/arch/blackfin/kernel/ptrace.c +++ b/arch/blackfin/kernel/ptrace.c @@ -1,6 +1,6 @@ /* * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds - * these modifications are Copyright 2004-2009 Analog Devices Inc. + * these modifications are Copyright 2004-2010 Analog Devices Inc. * * Licensed under the GPL-2 */ @@ -9,10 +9,13 @@ #include <linux/sched.h> #include <linux/mm.h> #include <linux/smp.h> +#include <linux/elf.h> #include <linux/errno.h> #include <linux/ptrace.h> #include <linux/user.h> +#include <linux/regset.h> #include <linux/signal.h> +#include <linux/tracehook.h> #include <linux/uaccess.h> #include <asm/page.h> @@ -25,90 +28,57 @@ #include <asm/cacheflush.h> #include <asm/mem_map.h> -#define TEXT_OFFSET 0 /* * does not yet catch signals sent when the child dies. * in exit.c or in signal.c. */ -/* determines which bits in the SYSCFG reg the user has access to. */ -/* 1 = access 0 = no access */ -#define SYSCFG_MASK 0x0007 /* SYSCFG reg */ -/* sets the trace bits. */ -#define TRACE_BITS 0x0001 - -/* Find the stack offset for a register, relative to thread.esp0. */ -#define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg) - -/* - * Get the address of the live pt_regs for the specified task. - * These are saved onto the top kernel stack when the process - * is not running. - * - * Note: if a user thread is execve'd from kernel space, the - * 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) -{ - return (struct pt_regs *) - ((unsigned long)task_stack_page(task) + - (THREAD_SIZE - sizeof(struct pt_regs))); -} - -/* - * Get all user integer registers. - */ -static inline int ptrace_getregs(struct task_struct *tsk, void __user *uregs) -{ - struct pt_regs regs; - memcpy(®s, get_user_regs(tsk), sizeof(regs)); - regs.usp = tsk->thread.usp; - return copy_to_user(uregs, ®s, sizeof(struct pt_regs)) ? -EFAULT : 0; -} - -/* Mapping from PT_xxx to the stack offset at which the register is - * saved. Notice that usp has no stack-slot and needs to be treated - * specially (see get_reg/put_reg below). - */ - /* * 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: @@ -125,10 +95,18 @@ 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; } @@ -160,24 +138,98 @@ static inline int is_user_addr_valid(struct task_struct *child, return -EIO; } -void ptrace_enable(struct task_struct *child) +/* + * retrieve the contents of Blackfin userspace general registers + */ +static int genregs_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + struct pt_regs *regs = task_pt_regs(target); + int ret; + + /* This sucks ... */ + regs->usp = target->thread.usp; + + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + regs, 0, sizeof(*regs)); + if (ret < 0) + return ret; + + return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, + sizeof(*regs), -1); +} + +/* + * update the contents of the Blackfin userspace general registers + */ +static int genregs_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 tmp; - tmp = get_reg(child, PT_SYSCFG) | (TRACE_BITS); - put_reg(child, PT_SYSCFG, tmp); + struct pt_regs *regs = task_pt_regs(target); + int ret; + + /* Don't let people set SYSCFG (it's at the end of pt_regs) */ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + regs, 0, PT_SYSCFG); + if (ret < 0) + return ret; + + /* This sucks ... */ + target->thread.usp = regs->usp; + /* regs->retx = regs->pc; */ + + return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, + PT_SYSCFG, -1); } /* - * Called by kernel/ptrace.c when detaching.. - * - * Make sure the single step bit is not set. + * Define the register sets available on the Blackfin under Linux */ -void ptrace_disable(struct task_struct *child) +enum bfin_regset { + REGSET_GENERAL, +}; + +static const struct user_regset bfin_regsets[] = { + [REGSET_GENERAL] = { + .core_note_type = NT_PRSTATUS, + .n = sizeof(struct pt_regs) / sizeof(long), + .size = sizeof(long), + .align = sizeof(long), + .get = genregs_get, + .set = genregs_set, + }, +}; + +static const struct user_regset_view user_bfin_native_view = { + .name = "Blackfin", + .e_machine = EM_BLACKFIN, + .regsets = bfin_regsets, + .n = ARRAY_SIZE(bfin_regsets), +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &user_bfin_native_view; +} + +void user_enable_single_step(struct task_struct *child) +{ + struct pt_regs *regs = task_pt_regs(child); + regs->syscfg |= SYSCFG_SSSTEP; + + set_tsk_thread_flag(child, TIF_SINGLESTEP); +} + +void user_disable_single_step(struct task_struct *child) { - unsigned long tmp; - /* make sure the single step bit is not set. */ - tmp = get_reg(child, PT_SYSCFG) & ~TRACE_BITS; - put_reg(child, PT_SYSCFG, tmp); + struct pt_regs *regs = task_pt_regs(child); + regs->syscfg &= ~SYSCFG_SSSTEP; + + clear_tsk_thread_flag(child, TIF_SINGLESTEP); } long arch_ptrace(struct task_struct *child, long request, long addr, long data) @@ -240,62 +292,6 @@ 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; - - switch (addr) { - case_PTRACE_GETFDPIC_EXEC: - case PTRACE_GETFDPIC_EXEC: - tmp = child->mm->context.exec_fdpic_loadmap; - break; - case_PTRACE_GETFDPIC_INTERP: - case PTRACE_GETFDPIC_INTERP: - tmp = child->mm->context.interp_fdpic_loadmap; - break; - default: - break; - } - - ret = put_user(tmp, datap); - break; - } -#endif - /* when I and D space are separate, this will have to be fixed. */ case PTRACE_POKEDATA: pr_debug("ptrace: PTRACE_PEEKDATA\n"); @@ -336,79 +332,44 @@ 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; - } - - if (addr >= (sizeof(struct pt_regs))) { - ret = 0; - break; - } - if (addr == PT_SYSCFG) { - data &= SYSCFG_MASK; - data |= get_reg(child, PT_SYSCFG); + case PTRACE_PEEKUSR: + switch (addr) { +#ifdef CONFIG_BINFMT_ELF_FDPIC /* backwards compat */ + case PT_FDPIC_EXEC: + request = PTRACE_GETFDPIC; + addr = PTRACE_GETFDPIC_EXEC; + goto case_default; + case PT_FDPIC_INTERP: + request = PTRACE_GETFDPIC; + addr = PTRACE_GETFDPIC_INTERP; + goto case_default; +#endif + default: + ret = get_reg(child, addr, datap); } - ret = put_reg(child, addr, data); - break; - - case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ - case PTRACE_CONT: /* restart after signal. */ - pr_debug("ptrace: syscall/cont\n"); - - ret = -EIO; - if (!valid_signal(data)) - break; - if (request == PTRACE_SYSCALL) - set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - else - clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - child->exit_code = data; - ptrace_disable(child); - pr_debug("ptrace: before wake_up_process\n"); - wake_up_process(child); - ret = 0; - break; - - /* - * make the child exit. Best I can do is send it a sigkill. - * perhaps it should be put in the status that it wants to - * exit. - */ - case PTRACE_KILL: - ret = 0; - if (child->exit_state == EXIT_ZOMBIE) /* already dead */ - break; - child->exit_code = SIGKILL; - ptrace_disable(child); - wake_up_process(child); + pr_debug("ptrace: PEEKUSR reg %li with %#lx = %i\n", addr, data, ret); break; - case PTRACE_SINGLESTEP: /* set the trap flag. */ - pr_debug("ptrace: single step\n"); - ret = -EIO; - if (!valid_signal(data)) - break; - clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); - ptrace_enable(child); - child->exit_code = data; - wake_up_process(child); - ret = 0; + 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: - /* Get all gp regs from the child. */ - ret = ptrace_getregs(child, datap); - break; + pr_debug("ptrace: PTRACE_GETREGS\n"); + return copy_regset_to_user(child, &user_bfin_native_view, + REGSET_GENERAL, + 0, sizeof(struct pt_regs), + (void __user *)data); case PTRACE_SETREGS: - printk(KERN_WARNING "ptrace: SETREGS: **** NOT IMPLEMENTED ***\n"); - /* Set all gp regs in the child. */ - ret = 0; - break; + pr_debug("ptrace: PTRACE_SETREGS\n"); + return copy_regset_from_user(child, &user_bfin_native_view, + REGSET_GENERAL, + 0, sizeof(struct pt_regs), + (const void __user *)data); + case_default: default: ret = ptrace_request(child, request, addr, data); break; @@ -417,27 +378,21 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) return ret; } -asmlinkage void syscall_trace(void) +asmlinkage int syscall_trace_enter(struct pt_regs *regs) { - if (!test_thread_flag(TIF_SYSCALL_TRACE)) - return; - - if (!(current->ptrace & PT_PTRACED)) - return; - - /* the 0x80 provides a way for the tracing parent to distinguish - * between a syscall stop and SIGTRAP delivery - */ - ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) - ? 0x80 : 0)); - - /* - * this isn't the same as continuing with a signal, but it will do - * for normal use. strace only continues with a signal if the - * stopping signal is not SIGTRAP. -brl - */ - if (current->exit_code) { - send_sig(current->exit_code, current, 1); - current->exit_code = 0; - } + int ret = 0; + + if (test_thread_flag(TIF_SYSCALL_TRACE)) + ret = tracehook_report_syscall_entry(regs); + + return ret; +} + +asmlinkage void syscall_trace_leave(struct pt_regs *regs) +{ + int step; + + step = test_thread_flag(TIF_SINGLESTEP); + if (step || test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall_exit(regs, step); } |