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-rw-r--r--arch/mips/kernel/ptrace.c338
1 files changed, 338 insertions, 0 deletions
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
new file mode 100644
index 000000000000..a166954a70b3
--- /dev/null
+++ b/arch/mips/kernel/ptrace.c
@@ -0,0 +1,338 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1992 Ross Biro
+ * Copyright (C) Linus Torvalds
+ * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
+ * Copyright (C) 1996 David S. Miller
+ * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 1999 MIPS Technologies, Inc.
+ * Copyright (C) 2000 Ulf Carlsson
+ *
+ * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
+ * binaries.
+ */
+#include <linux/config.h>
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/audit.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/audit.h>
+
+#include <asm/cpu.h>
+#include <asm/fpu.h>
+#include <asm/mipsregs.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/bootinfo.h>
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ /* Nothing to do.. */
+}
+
+asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+{
+ struct task_struct *child;
+ int ret;
+
+#if 0
+ printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n",
+ (int) request, (int) pid, (unsigned long) addr,
+ (unsigned long) data);
+#endif
+ lock_kernel();
+ ret = -EPERM;
+ if (request == PTRACE_TRACEME) {
+ /* are we already being traced? */
+ if (current->ptrace & PT_PTRACED)
+ goto out;
+ if ((ret = security_ptrace(current->parent, current)))
+ goto out;
+ /* set the ptrace bit in the process flags. */
+ current->ptrace |= PT_PTRACED;
+ ret = 0;
+ goto out;
+ }
+ ret = -ESRCH;
+ read_lock(&tasklist_lock);
+ child = find_task_by_pid(pid);
+ if (child)
+ get_task_struct(child);
+ read_unlock(&tasklist_lock);
+ if (!child)
+ goto out;
+
+ ret = -EPERM;
+ if (pid == 1) /* you may not mess with init */
+ goto out_tsk;
+
+ if (request == PTRACE_ATTACH) {
+ ret = ptrace_attach(child);
+ goto out_tsk;
+ }
+
+ ret = ptrace_check_attach(child, request == PTRACE_KILL);
+ if (ret < 0)
+ goto out_tsk;
+
+ switch (request) {
+ /* when I and D space are separate, these will need to be fixed. */
+ case PTRACE_PEEKTEXT: /* read word at location addr. */
+ case PTRACE_PEEKDATA: {
+ unsigned long tmp;
+ int copied;
+
+ copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+ ret = -EIO;
+ 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: {
+ struct pt_regs *regs;
+ unsigned long tmp = 0;
+
+ regs = (struct pt_regs *) ((unsigned long) child->thread_info +
+ THREAD_SIZE - 32 - sizeof(struct pt_regs));
+ ret = 0; /* Default return value. */
+
+ switch (addr) {
+ case 0 ... 31:
+ tmp = regs->regs[addr];
+ break;
+ case FPR_BASE ... FPR_BASE + 31:
+ if (tsk_used_math(child)) {
+ fpureg_t *fregs = get_fpu_regs(child);
+
+#ifdef CONFIG_MIPS32
+ /*
+ * The odd registers are actually the high
+ * order bits of the values stored in the even
+ * registers - unless we're using r2k_switch.S.
+ */
+ if (addr & 1)
+ tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32);
+ else
+ tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff);
+#endif
+#ifdef CONFIG_MIPS64
+ tmp = fregs[addr - FPR_BASE];
+#endif
+ } else {
+ tmp = -1; /* FP not yet used */
+ }
+ break;
+ case PC:
+ tmp = regs->cp0_epc;
+ break;
+ case CAUSE:
+ tmp = regs->cp0_cause;
+ break;
+ case BADVADDR:
+ tmp = regs->cp0_badvaddr;
+ break;
+ case MMHI:
+ tmp = regs->hi;
+ break;
+ case MMLO:
+ tmp = regs->lo;
+ break;
+ case FPC_CSR:
+ if (cpu_has_fpu)
+ tmp = child->thread.fpu.hard.fcr31;
+ else
+ tmp = child->thread.fpu.soft.fcr31;
+ break;
+ case FPC_EIR: { /* implementation / version register */
+ unsigned int flags;
+
+ if (!cpu_has_fpu)
+ break;
+
+ flags = read_c0_status();
+ __enable_fpu();
+ __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
+ write_c0_status(flags);
+ break;
+ }
+ default:
+ tmp = 0;
+ ret = -EIO;
+ goto out_tsk;
+ }
+ ret = put_user(tmp, (unsigned long *) data);
+ break;
+ }
+
+ /* when I and D space are separate, this will have to be fixed. */
+ case PTRACE_POKETEXT: /* write the word at location addr. */
+ case PTRACE_POKEDATA:
+ ret = 0;
+ if (access_process_vm(child, addr, &data, sizeof(data), 1)
+ == sizeof(data))
+ break;
+ ret = -EIO;
+ break;
+
+ case PTRACE_POKEUSR: {
+ struct pt_regs *regs;
+ ret = 0;
+ regs = (struct pt_regs *) ((unsigned long) child->thread_info +
+ THREAD_SIZE - 32 - sizeof(struct pt_regs));
+
+ switch (addr) {
+ case 0 ... 31:
+ regs->regs[addr] = data;
+ break;
+ case FPR_BASE ... FPR_BASE + 31: {
+ fpureg_t *fregs = get_fpu_regs(child);
+
+ if (!tsk_used_math(child)) {
+ /* FP not yet used */
+ memset(&child->thread.fpu.hard, ~0,
+ sizeof(child->thread.fpu.hard));
+ child->thread.fpu.hard.fcr31 = 0;
+ }
+#ifdef CONFIG_MIPS32
+ /*
+ * The odd registers are actually the high order bits
+ * of the values stored in the even registers - unless
+ * we're using r2k_switch.S.
+ */
+ if (addr & 1) {
+ fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff;
+ fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32;
+ } else {
+ fregs[addr - FPR_BASE] &= ~0xffffffffLL;
+ fregs[addr - FPR_BASE] |= data;
+ }
+#endif
+#ifdef CONFIG_MIPS64
+ fregs[addr - FPR_BASE] = data;
+#endif
+ break;
+ }
+ case PC:
+ regs->cp0_epc = data;
+ break;
+ case MMHI:
+ regs->hi = data;
+ break;
+ case MMLO:
+ regs->lo = data;
+ break;
+ case FPC_CSR:
+ if (cpu_has_fpu)
+ child->thread.fpu.hard.fcr31 = data;
+ else
+ child->thread.fpu.soft.fcr31 = data;
+ break;
+ default:
+ /* The rest are not allowed. */
+ ret = -EIO;
+ break;
+ }
+ break;
+ }
+
+ case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+ case PTRACE_CONT: { /* restart after signal. */
+ ret = -EIO;
+ if ((unsigned long) data > _NSIG)
+ 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;
+ 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;
+ wake_up_process(child);
+ break;
+
+ case PTRACE_DETACH: /* detach a process that was attached. */
+ ret = ptrace_detach(child, data);
+ break;
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+out_tsk:
+ put_task_struct(child);
+out:
+ unlock_kernel();
+ return ret;
+}
+
+/*
+ * Notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
+{
+ if (unlikely(current->audit_context)) {
+ if (!entryexit)
+ audit_syscall_entry(current, regs->regs[2],
+ regs->regs[4], regs->regs[5],
+ regs->regs[6], regs->regs[7]);
+ else
+ audit_syscall_exit(current, regs->regs[2]);
+ }
+
+ 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;
+ }
+}
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