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-rw-r--r--arch/blackfin/kernel/ptrace.c430
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diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c
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+/*
+ * File: arch/blackfin/kernel/ptrace.c
+ * Based on: Taken from linux/kernel/ptrace.c
+ * Author: linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
+ *
+ * Created: 1/23/92
+ * Description:
+ *
+ * Modified:
+ * Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs: Enter bugs at http://blackfin.uclinux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/signal.h>
+
+#include <asm/uaccess.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/asm-offsets.h>
+#include <asm/dma.h>
+
+#define MAX_SHARED_LIBS 3
+#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->thread_info +
+ (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 = get_user_regs(tsk);
+ return copy_to_user(uregs, regs, 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)
+{
+ unsigned char *reg_ptr;
+
+ struct pt_regs *regs =
+ (struct pt_regs *)((unsigned long)task->thread_info +
+ (THREAD_SIZE - sizeof(struct pt_regs)));
+ reg_ptr = (char *)regs;
+
+ switch (regno) {
+ case PT_USP:
+ return task->thread.usp;
+ default:
+ if (regno <= 216)
+ return *(long *)(reg_ptr + regno);
+ }
+ /* 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;
+}
+
+/*
+ * Write contents of register REGNO in task TASK.
+ */
+static inline int
+put_reg(struct task_struct *task, int regno, unsigned long data)
+{
+ char * reg_ptr;
+
+ struct pt_regs *regs =
+ (struct pt_regs *)((unsigned long)task->thread_info +
+ (THREAD_SIZE - sizeof(struct pt_regs)));
+ reg_ptr = (char *)regs;
+
+ switch (regno) {
+ case PT_PC:
+ /*********************************************************************/
+ /* At this point the kernel is most likely in exception. */
+ /* The RETX register will be used to populate the pc of the process. */
+ /*********************************************************************/
+ regs->retx = data;
+ regs->pc = data;
+ break;
+ case PT_RETX:
+ break; /* regs->retx = data; break; */
+ case PT_USP:
+ regs->usp = data;
+ task->thread.usp = data;
+ break;
+ default:
+ if (regno <= 216)
+ *(long *)(reg_ptr + regno) = data;
+ }
+ return 0;
+}
+
+/*
+ * check that an address falls within the bounds of the target process's memory mappings
+ */
+static inline int is_user_addr_valid(struct task_struct *child,
+ unsigned long start, unsigned long len)
+{
+ struct vm_list_struct *vml;
+ struct sram_list_struct *sraml;
+
+ for (vml = child->mm->context.vmlist; vml; vml = vml->next)
+ if (start >= vml->vma->vm_start && start + len <= vml->vma->vm_end)
+ return 0;
+
+ for (sraml = child->mm->context.sram_list; sraml; sraml = sraml->next)
+ if (start >= (unsigned long)sraml->addr
+ && start + len <= (unsigned long)sraml->addr + sraml->length)
+ return 0;
+
+ return -EIO;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure the single step bit is not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ unsigned long tmp;
+ /* make sure the single step bit is not set. */
+ tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
+ put_reg(child, PT_SR, tmp);
+}
+
+long arch_ptrace(struct task_struct *child, long request, long addr, long data)
+{
+ int ret;
+ int add = 0;
+
+ switch (request) {
+ /* when I and D space are separate, these will need to be fixed. */
+ case PTRACE_PEEKDATA:
+ pr_debug("ptrace: PEEKDATA\n");
+ add = MAX_SHARED_LIBS * 4; /* space between text and data */
+ /* fall through */
+ case PTRACE_PEEKTEXT: /* read word at location addr. */
+ {
+ unsigned long tmp = 0;
+ int copied;
+
+ ret = -EIO;
+ pr_debug("ptrace: PEEKTEXT at addr 0x%08lx + add %d %ld\n", addr, add,
+ sizeof(data));
+ if (is_user_addr_valid(child, addr + add, sizeof(tmp)) < 0)
+ break;
+ pr_debug("ptrace: user address is valid\n");
+
+#if L1_CODE_LENGTH != 0
+ if (addr + add >= L1_CODE_START
+ && addr + add + sizeof(tmp) <= L1_CODE_START + L1_CODE_LENGTH) {
+ safe_dma_memcpy (&tmp, (const void *)(addr + add), sizeof(tmp));
+ copied = sizeof(tmp);
+ } else
+#endif
+ copied =
+ access_process_vm(child, addr + add, &tmp,
+ sizeof(tmp), 0);
+ pr_debug("ptrace: copied size %d [0x%08lx]\n", copied, tmp);
+ if (copied != sizeof(tmp))
+ break;
+ ret = put_user(tmp, (unsigned 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)) {
+ tmp = child->mm->context.exec_fdpic_loadmap;
+ } else if (addr == (sizeof(struct pt_regs) + 16)) {
+ tmp = child->mm->context.interp_fdpic_loadmap;
+#endif
+ } else {
+ tmp = get_reg(child, addr);
+ }
+ ret = put_user(tmp, (unsigned long *)data);
+ break;
+ }
+
+ /* when I and D space are separate, this will have to be fixed. */
+ case PTRACE_POKEDATA:
+ printk(KERN_NOTICE "ptrace: PTRACE_PEEKDATA\n");
+ /* fall through */
+ case PTRACE_POKETEXT: /* write the word at location addr. */
+ {
+ int copied;
+
+ ret = -EIO;
+ pr_debug("ptrace: POKETEXT at addr 0x%08lx + add %d %ld bytes %lx\n",
+ addr, add, sizeof(data), data);
+ if (is_user_addr_valid(child, addr + add, sizeof(data)) < 0)
+ break;
+ pr_debug("ptrace: user address is valid\n");
+
+#if L1_CODE_LENGTH != 0
+ if (addr + add >= L1_CODE_START
+ && addr + add + sizeof(data) <= L1_CODE_START + L1_CODE_LENGTH) {
+ safe_dma_memcpy ((void *)(addr + add), &data, sizeof(data));
+ copied = sizeof(data);
+ } else
+#endif
+ copied =
+ access_process_vm(child, addr + add, &data,
+ sizeof(data), 1);
+ pr_debug("ptrace: copied size %d\n", copied);
+ if (copied != sizeof(data))
+ break;
+ ret = 0;
+ 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);
+ }
+ ret = put_reg(child, addr, data);
+ break;
+
+ case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+ case PTRACE_CONT:
+ { /* restart after signal. */
+ long tmp;
+
+ pr_debug("ptrace_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;
+ /* make sure the single step bit is not set. */
+ tmp = get_reg(child, PT_SYSCFG) & ~(TRACE_BITS);
+ put_reg(child, PT_SYSCFG, tmp);
+ pr_debug("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:
+ {
+ long tmp;
+ ret = 0;
+ if (child->exit_state == EXIT_ZOMBIE) /* already dead */
+ break;
+ child->exit_code = SIGKILL;
+ /* make sure the single step bit is not set. */
+ tmp = get_reg(child, PT_SYSCFG) & ~(TRACE_BITS);
+ put_reg(child, PT_SYSCFG, tmp);
+ wake_up_process(child);
+ break;
+ }
+
+ case PTRACE_SINGLESTEP:
+ { /* set the trap flag. */
+ long tmp;
+
+ pr_debug("single step\n");
+ ret = -EIO;
+ if (!valid_signal(data))
+ break;
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+
+ tmp = get_reg(child, PT_SYSCFG) | (TRACE_BITS);
+ put_reg(child, PT_SYSCFG, tmp);
+
+ child->exit_code = data;
+ /* give it a chance to run. */
+ wake_up_process(child);
+ ret = 0;
+ break;
+ }
+
+ case PTRACE_DETACH:
+ { /* detach a process that was attached. */
+ ret = ptrace_detach(child, data);
+ break;
+ }
+
+ case PTRACE_GETREGS:
+ {
+
+ /* Get all gp regs from the child. */
+ ret = ptrace_getregs(child, (void __user *)data);
+ break;
+ }
+
+ case PTRACE_SETREGS:
+ {
+ printk(KERN_NOTICE
+ "ptrace: SETREGS: **** NOT IMPLEMENTED ***\n");
+ /* Set all gp regs in the child. */
+ ret = 0;
+ break;
+ }
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+asmlinkage void syscall_trace(void)
+{
+
+ 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;
+ }
+}