x86: ptrace_32 renamed
authorRoland McGrath <roland@redhat.com>
Wed, 30 Jan 2008 12:31:01 +0000 (13:31 +0100)
committerIngo Molnar <mingo@elte.hu>
Wed, 30 Jan 2008 12:31:01 +0000 (13:31 +0100)
This renames ptrace_32.c back to ptrace.c, in preparation
for merging the 32/64 versions of these files.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kernel/Makefile_32
arch/x86/kernel/ptrace.c [new file with mode: 0644]
arch/x86/kernel/ptrace_32.c [deleted file]

index 20e23c4c18b6abf0a80a6924d89635cf26764a63..b2d7aea4c82d46a8482f046c006e3d03feb7f4ba 100644 (file)
@@ -6,10 +6,11 @@ extra-y := head_32.o init_task.o vmlinux.lds
 CPPFLAGS_vmlinux.lds += -Ui386
 
 obj-y  := process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \
-               ptrace_32.o time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
+               time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
                pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
                quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o io_delay.o rtc.o
 
+obj-y                          += ptrace.o
 obj-y                          += tls.o
 obj-y                          += step.o
 obj-$(CONFIG_STACKTRACE)       += stacktrace.o
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
new file mode 100644 (file)
index 0000000..fed83d0
--- /dev/null
@@ -0,0 +1,484 @@
+/* By Ross Biro 1/23/92 */
+/*
+ * Pentium III FXSR, SSE support
+ *     Gareth Hughes <gareth@valinux.com>, May 2000
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/signal.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+#include <asm/debugreg.h>
+#include <asm/ldt.h>
+#include <asm/desc.h>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * Determines which flags the user has access to [1 = access, 0 = no access].
+ * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), NT(14), IOPL(12-13), IF(9).
+ * Also masks reserved bits (31-22, 15, 5, 3, 1).
+ */
+#define FLAG_MASK 0x00050dd5
+
+static long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
+{
+       BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
+       if (regno > FS)
+               --regno;
+       return &regs->bx + regno;
+}
+
+static int putreg(struct task_struct *child,
+       unsigned long regno, unsigned long value)
+{
+       struct pt_regs *regs = task_pt_regs(child);
+       regno >>= 2;
+       switch (regno) {
+       case GS:
+               if (value && (value & 3) != 3)
+                       return -EIO;
+               child->thread.gs = value;
+               if (child == current)
+                       /*
+                        * The user-mode %gs is not affected by
+                        * kernel entry, so we must update the CPU.
+                        */
+                       loadsegment(gs, value);
+               return 0;
+       case DS:
+       case ES:
+       case FS:
+               if (value && (value & 3) != 3)
+                       return -EIO;
+               value &= 0xffff;
+               break;
+       case SS:
+       case CS:
+               if ((value & 3) != 3)
+                       return -EIO;
+               value &= 0xffff;
+               break;
+       case EFL:
+               value &= FLAG_MASK;
+               /*
+                * If the user value contains TF, mark that
+                * it was not "us" (the debugger) that set it.
+                * If not, make sure it stays set if we had.
+                */
+               if (value & X86_EFLAGS_TF)
+                       clear_tsk_thread_flag(child, TIF_FORCED_TF);
+               else if (test_tsk_thread_flag(child, TIF_FORCED_TF))
+                       value |= X86_EFLAGS_TF;
+               value |= regs->flags & ~FLAG_MASK;
+               break;
+       }
+       *pt_regs_access(regs, regno) = value;
+       return 0;
+}
+
+static unsigned long getreg(struct task_struct *child, unsigned long regno)
+{
+       struct pt_regs *regs = task_pt_regs(child);
+       unsigned long retval = ~0UL;
+
+       regno >>= 2;
+       switch (regno) {
+       case EFL:
+               /*
+                * If the debugger set TF, hide it from the readout.
+                */
+               retval = regs->flags;
+               if (test_tsk_thread_flag(child, TIF_FORCED_TF))
+                       retval &= ~X86_EFLAGS_TF;
+               break;
+       case GS:
+               retval = child->thread.gs;
+               if (child == current)
+                       savesegment(gs, retval);
+               break;
+       case DS:
+       case ES:
+       case FS:
+       case SS:
+       case CS:
+               retval = 0xffff;
+               /* fall through */
+       default:
+               retval &= *pt_regs_access(regs, regno);
+       }
+       return retval;
+}
+
+/*
+ * This function is trivial and will be inlined by the compiler.
+ * Having it separates the implementation details of debug
+ * registers from the interface details of ptrace.
+ */
+static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
+{
+       switch (n) {
+       case 0:         return child->thread.debugreg0;
+       case 1:         return child->thread.debugreg1;
+       case 2:         return child->thread.debugreg2;
+       case 3:         return child->thread.debugreg3;
+       case 6:         return child->thread.debugreg6;
+       case 7:         return child->thread.debugreg7;
+       }
+       return 0;
+}
+
+static int ptrace_set_debugreg(struct task_struct *child,
+                              int n, unsigned long data)
+{
+       int i;
+
+       if (unlikely(n == 4 || n == 5))
+               return -EIO;
+
+       if (n < 4 && unlikely(data >= TASK_SIZE - 3))
+               return -EIO;
+
+       switch (n) {
+       case 0:         child->thread.debugreg0 = data; break;
+       case 1:         child->thread.debugreg1 = data; break;
+       case 2:         child->thread.debugreg2 = data; break;
+       case 3:         child->thread.debugreg3 = data; break;
+
+       case 6:
+               child->thread.debugreg6 = data;
+               break;
+
+       case 7:
+               /*
+                * Sanity-check data. Take one half-byte at once with
+                * check = (val >> (16 + 4*i)) & 0xf. It contains the
+                * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
+                * 2 and 3 are LENi. Given a list of invalid values,
+                * we do mask |= 1 << invalid_value, so that
+                * (mask >> check) & 1 is a correct test for invalid
+                * values.
+                *
+                * R/Wi contains the type of the breakpoint /
+                * watchpoint, LENi contains the length of the watched
+                * data in the watchpoint case.
+                *
+                * The invalid values are:
+                * - LENi == 0x10 (undefined), so mask |= 0x0f00.
+                * - R/Wi == 0x10 (break on I/O reads or writes), so
+                *   mask |= 0x4444.
+                * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
+                *   0x1110.
+                *
+                * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
+                *
+                * See the Intel Manual "System Programming Guide",
+                * 15.2.4
+                *
+                * Note that LENi == 0x10 is defined on x86_64 in long
+                * mode (i.e. even for 32-bit userspace software, but
+                * 64-bit kernel), so the x86_64 mask value is 0x5454.
+                * See the AMD manual no. 24593 (AMD64 System Programming)
+                */
+               data &= ~DR_CONTROL_RESERVED;
+               for (i = 0; i < 4; i++)
+                       if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
+                               return -EIO;
+               child->thread.debugreg7 = data;
+               if (data)
+                       set_tsk_thread_flag(child, TIF_DEBUG);
+               else
+                       clear_tsk_thread_flag(child, TIF_DEBUG);
+               break;
+       }
+
+       return 0;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure the single step bit is not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+       user_disable_single_step(child);
+       clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+}
+
+long arch_ptrace(struct task_struct *child, long request, long addr, long data)
+{
+       struct user * dummy = NULL;
+       int i, ret;
+       unsigned long __user *datap = (unsigned long __user *)data;
+
+       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:
+               ret = generic_ptrace_peekdata(child, addr, data);
+               break;
+
+       /* read the word at location addr in the USER area. */
+       case PTRACE_PEEKUSR: {
+               unsigned long tmp;
+
+               ret = -EIO;
+               if ((addr & 3) || addr < 0 ||
+                   addr > sizeof(struct user) - 3)
+                       break;
+
+               tmp = 0;  /* Default return condition */
+               if(addr < FRAME_SIZE*sizeof(long))
+                       tmp = getreg(child, addr);
+               if(addr >= (long) &dummy->u_debugreg[0] &&
+                  addr <= (long) &dummy->u_debugreg[7]){
+                       addr -= (long) &dummy->u_debugreg[0];
+                       addr = addr >> 2;
+                       tmp = ptrace_get_debugreg(child, addr);
+               }
+               ret = put_user(tmp, datap);
+               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 = generic_ptrace_pokedata(child, addr, data);
+               break;
+
+       case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
+               ret = -EIO;
+               if ((addr & 3) || addr < 0 ||
+                   addr > sizeof(struct user) - 3)
+                       break;
+
+               if (addr < FRAME_SIZE*sizeof(long)) {
+                       ret = putreg(child, addr, data);
+                       break;
+               }
+               /* We need to be very careful here.  We implicitly
+                  want to modify a portion of the task_struct, and we
+                  have to be selective about what portions we allow someone
+                  to modify. */
+
+                 ret = -EIO;
+                 if(addr >= (long) &dummy->u_debugreg[0] &&
+                    addr <= (long) &dummy->u_debugreg[7]){
+                         addr -= (long) &dummy->u_debugreg;
+                         addr = addr >> 2;
+                         ret = ptrace_set_debugreg(child, addr, data);
+                 }
+                 break;
+
+       case PTRACE_GETREGS: { /* Get all gp regs from the child. */
+               if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) {
+                       ret = -EIO;
+                       break;
+               }
+               for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+                       __put_user(getreg(child, i), datap);
+                       datap++;
+               }
+               ret = 0;
+               break;
+       }
+
+       case PTRACE_SETREGS: { /* Set all gp regs in the child. */
+               unsigned long tmp;
+               if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) {
+                       ret = -EIO;
+                       break;
+               }
+               for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+                       __get_user(tmp, datap);
+                       putreg(child, i, tmp);
+                       datap++;
+               }
+               ret = 0;
+               break;
+       }
+
+       case PTRACE_GETFPREGS: { /* Get the child FPU state. */
+               if (!access_ok(VERIFY_WRITE, datap,
+                              sizeof(struct user_i387_struct))) {
+                       ret = -EIO;
+                       break;
+               }
+               ret = 0;
+               if (!tsk_used_math(child))
+                       init_fpu(child);
+               get_fpregs((struct user_i387_struct __user *)data, child);
+               break;
+       }
+
+       case PTRACE_SETFPREGS: { /* Set the child FPU state. */
+               if (!access_ok(VERIFY_READ, datap,
+                              sizeof(struct user_i387_struct))) {
+                       ret = -EIO;
+                       break;
+               }
+               set_stopped_child_used_math(child);
+               set_fpregs(child, (struct user_i387_struct __user *)data);
+               ret = 0;
+               break;
+       }
+
+       case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
+               if (!access_ok(VERIFY_WRITE, datap,
+                              sizeof(struct user_fxsr_struct))) {
+                       ret = -EIO;
+                       break;
+               }
+               if (!tsk_used_math(child))
+                       init_fpu(child);
+               ret = get_fpxregs((struct user_fxsr_struct __user *)data, child);
+               break;
+       }
+
+       case PTRACE_SETFPXREGS: { /* Set the child extended FPU state. */
+               if (!access_ok(VERIFY_READ, datap,
+                              sizeof(struct user_fxsr_struct))) {
+                       ret = -EIO;
+                       break;
+               }
+               set_stopped_child_used_math(child);
+               ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
+               break;
+       }
+
+       case PTRACE_GET_THREAD_AREA:
+               if (addr < 0)
+                       return -EIO;
+               ret = do_get_thread_area(child, addr,
+                                        (struct user_desc __user *) data);
+               break;
+
+       case PTRACE_SET_THREAD_AREA:
+               if (addr < 0)
+                       return -EIO;
+               ret = do_set_thread_area(child, addr,
+                                        (struct user_desc __user *) data, 0);
+               break;
+
+       default:
+               ret = ptrace_request(child, request, addr, data);
+               break;
+       }
+
+       return ret;
+}
+
+void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
+{
+       struct siginfo info;
+
+       tsk->thread.trap_no = 1;
+       tsk->thread.error_code = error_code;
+
+       memset(&info, 0, sizeof(info));
+       info.si_signo = SIGTRAP;
+       info.si_code = TRAP_BRKPT;
+
+       /* User-mode ip? */
+       info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
+
+       /* Send us the fake SIGTRAP */
+       force_sig_info(SIGTRAP, &info, tsk);
+}
+
+/* notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+__attribute__((regparm(3)))
+int do_syscall_trace(struct pt_regs *regs, int entryexit)
+{
+       int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
+       /*
+        * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
+        * interception
+        */
+       int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
+       int ret = 0;
+
+       /* do the secure computing check first */
+       if (!entryexit)
+               secure_computing(regs->orig_ax);
+
+       if (unlikely(current->audit_context)) {
+               if (entryexit)
+                       audit_syscall_exit(AUDITSC_RESULT(regs->ax),
+                                               regs->ax);
+               /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
+                * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
+                * not used, entry.S will call us only on syscall exit, not
+                * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
+                * calling send_sigtrap() on syscall entry.
+                *
+                * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
+                * is_singlestep is false, despite his name, so we will still do
+                * the correct thing.
+                */
+               else if (is_singlestep)
+                       goto out;
+       }
+
+       if (!(current->ptrace & PT_PTRACED))
+               goto out;
+
+       /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
+        * and then is resumed with SYSEMU_SINGLESTEP, it will come in
+        * here. We have to check this and return */
+       if (is_sysemu && entryexit)
+               return 0;
+
+       /* Fake a debug trap */
+       if (is_singlestep)
+               send_sigtrap(current, regs, 0);
+
+       if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
+               goto out;
+
+       /* the 0x80 provides a way for the tracing parent to distinguish
+          between a syscall stop and SIGTRAP delivery */
+       /* Note that the debugger could change the result of test_thread_flag!*/
+       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;
+       }
+       ret = is_sysemu;
+out:
+       if (unlikely(current->audit_context) && !entryexit)
+               audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
+                                   regs->bx, regs->cx, regs->dx, regs->si);
+       if (ret == 0)
+               return 0;
+
+       regs->orig_ax = -1; /* force skip of syscall restarting */
+       if (unlikely(current->audit_context))
+               audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
+       return 1;
+}
diff --git a/arch/x86/kernel/ptrace_32.c b/arch/x86/kernel/ptrace_32.c
deleted file mode 100644 (file)
index fed83d0..0000000
+++ /dev/null
@@ -1,484 +0,0 @@
-/* By Ross Biro 1/23/92 */
-/*
- * Pentium III FXSR, SSE support
- *     Gareth Hughes <gareth@valinux.com>, May 2000
- */
-
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/errno.h>
-#include <linux/ptrace.h>
-#include <linux/user.h>
-#include <linux/security.h>
-#include <linux/audit.h>
-#include <linux/seccomp.h>
-#include <linux/signal.h>
-
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
-#include <asm/processor.h>
-#include <asm/i387.h>
-#include <asm/debugreg.h>
-#include <asm/ldt.h>
-#include <asm/desc.h>
-
-/*
- * does not yet catch signals sent when the child dies.
- * in exit.c or in signal.c.
- */
-
-/*
- * Determines which flags the user has access to [1 = access, 0 = no access].
- * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), NT(14), IOPL(12-13), IF(9).
- * Also masks reserved bits (31-22, 15, 5, 3, 1).
- */
-#define FLAG_MASK 0x00050dd5
-
-static long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
-{
-       BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
-       if (regno > FS)
-               --regno;
-       return &regs->bx + regno;
-}
-
-static int putreg(struct task_struct *child,
-       unsigned long regno, unsigned long value)
-{
-       struct pt_regs *regs = task_pt_regs(child);
-       regno >>= 2;
-       switch (regno) {
-       case GS:
-               if (value && (value & 3) != 3)
-                       return -EIO;
-               child->thread.gs = value;
-               if (child == current)
-                       /*
-                        * The user-mode %gs is not affected by
-                        * kernel entry, so we must update the CPU.
-                        */
-                       loadsegment(gs, value);
-               return 0;
-       case DS:
-       case ES:
-       case FS:
-               if (value && (value & 3) != 3)
-                       return -EIO;
-               value &= 0xffff;
-               break;
-       case SS:
-       case CS:
-               if ((value & 3) != 3)
-                       return -EIO;
-               value &= 0xffff;
-               break;
-       case EFL:
-               value &= FLAG_MASK;
-               /*
-                * If the user value contains TF, mark that
-                * it was not "us" (the debugger) that set it.
-                * If not, make sure it stays set if we had.
-                */
-               if (value & X86_EFLAGS_TF)
-                       clear_tsk_thread_flag(child, TIF_FORCED_TF);
-               else if (test_tsk_thread_flag(child, TIF_FORCED_TF))
-                       value |= X86_EFLAGS_TF;
-               value |= regs->flags & ~FLAG_MASK;
-               break;
-       }
-       *pt_regs_access(regs, regno) = value;
-       return 0;
-}
-
-static unsigned long getreg(struct task_struct *child, unsigned long regno)
-{
-       struct pt_regs *regs = task_pt_regs(child);
-       unsigned long retval = ~0UL;
-
-       regno >>= 2;
-       switch (regno) {
-       case EFL:
-               /*
-                * If the debugger set TF, hide it from the readout.
-                */
-               retval = regs->flags;
-               if (test_tsk_thread_flag(child, TIF_FORCED_TF))
-                       retval &= ~X86_EFLAGS_TF;
-               break;
-       case GS:
-               retval = child->thread.gs;
-               if (child == current)
-                       savesegment(gs, retval);
-               break;
-       case DS:
-       case ES:
-       case FS:
-       case SS:
-       case CS:
-               retval = 0xffff;
-               /* fall through */
-       default:
-               retval &= *pt_regs_access(regs, regno);
-       }
-       return retval;
-}
-
-/*
- * This function is trivial and will be inlined by the compiler.
- * Having it separates the implementation details of debug
- * registers from the interface details of ptrace.
- */
-static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
-{
-       switch (n) {
-       case 0:         return child->thread.debugreg0;
-       case 1:         return child->thread.debugreg1;
-       case 2:         return child->thread.debugreg2;
-       case 3:         return child->thread.debugreg3;
-       case 6:         return child->thread.debugreg6;
-       case 7:         return child->thread.debugreg7;
-       }
-       return 0;
-}
-
-static int ptrace_set_debugreg(struct task_struct *child,
-                              int n, unsigned long data)
-{
-       int i;
-
-       if (unlikely(n == 4 || n == 5))
-               return -EIO;
-
-       if (n < 4 && unlikely(data >= TASK_SIZE - 3))
-               return -EIO;
-
-       switch (n) {
-       case 0:         child->thread.debugreg0 = data; break;
-       case 1:         child->thread.debugreg1 = data; break;
-       case 2:         child->thread.debugreg2 = data; break;
-       case 3:         child->thread.debugreg3 = data; break;
-
-       case 6:
-               child->thread.debugreg6 = data;
-               break;
-
-       case 7:
-               /*
-                * Sanity-check data. Take one half-byte at once with
-                * check = (val >> (16 + 4*i)) & 0xf. It contains the
-                * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
-                * 2 and 3 are LENi. Given a list of invalid values,
-                * we do mask |= 1 << invalid_value, so that
-                * (mask >> check) & 1 is a correct test for invalid
-                * values.
-                *
-                * R/Wi contains the type of the breakpoint /
-                * watchpoint, LENi contains the length of the watched
-                * data in the watchpoint case.
-                *
-                * The invalid values are:
-                * - LENi == 0x10 (undefined), so mask |= 0x0f00.
-                * - R/Wi == 0x10 (break on I/O reads or writes), so
-                *   mask |= 0x4444.
-                * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
-                *   0x1110.
-                *
-                * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
-                *
-                * See the Intel Manual "System Programming Guide",
-                * 15.2.4
-                *
-                * Note that LENi == 0x10 is defined on x86_64 in long
-                * mode (i.e. even for 32-bit userspace software, but
-                * 64-bit kernel), so the x86_64 mask value is 0x5454.
-                * See the AMD manual no. 24593 (AMD64 System Programming)
-                */
-               data &= ~DR_CONTROL_RESERVED;
-               for (i = 0; i < 4; i++)
-                       if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
-                               return -EIO;
-               child->thread.debugreg7 = data;
-               if (data)
-                       set_tsk_thread_flag(child, TIF_DEBUG);
-               else
-                       clear_tsk_thread_flag(child, TIF_DEBUG);
-               break;
-       }
-
-       return 0;
-}
-
-/*
- * Called by kernel/ptrace.c when detaching..
- *
- * Make sure the single step bit is not set.
- */
-void ptrace_disable(struct task_struct *child)
-{
-       user_disable_single_step(child);
-       clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
-}
-
-long arch_ptrace(struct task_struct *child, long request, long addr, long data)
-{
-       struct user * dummy = NULL;
-       int i, ret;
-       unsigned long __user *datap = (unsigned long __user *)data;
-
-       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:
-               ret = generic_ptrace_peekdata(child, addr, data);
-               break;
-
-       /* read the word at location addr in the USER area. */
-       case PTRACE_PEEKUSR: {
-               unsigned long tmp;
-
-               ret = -EIO;
-               if ((addr & 3) || addr < 0 ||
-                   addr > sizeof(struct user) - 3)
-                       break;
-
-               tmp = 0;  /* Default return condition */
-               if(addr < FRAME_SIZE*sizeof(long))
-                       tmp = getreg(child, addr);
-               if(addr >= (long) &dummy->u_debugreg[0] &&
-                  addr <= (long) &dummy->u_debugreg[7]){
-                       addr -= (long) &dummy->u_debugreg[0];
-                       addr = addr >> 2;
-                       tmp = ptrace_get_debugreg(child, addr);
-               }
-               ret = put_user(tmp, datap);
-               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 = generic_ptrace_pokedata(child, addr, data);
-               break;
-
-       case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
-               ret = -EIO;
-               if ((addr & 3) || addr < 0 ||
-                   addr > sizeof(struct user) - 3)
-                       break;
-
-               if (addr < FRAME_SIZE*sizeof(long)) {
-                       ret = putreg(child, addr, data);
-                       break;
-               }
-               /* We need to be very careful here.  We implicitly
-                  want to modify a portion of the task_struct, and we
-                  have to be selective about what portions we allow someone
-                  to modify. */
-
-                 ret = -EIO;
-                 if(addr >= (long) &dummy->u_debugreg[0] &&
-                    addr <= (long) &dummy->u_debugreg[7]){
-                         addr -= (long) &dummy->u_debugreg;
-                         addr = addr >> 2;
-                         ret = ptrace_set_debugreg(child, addr, data);
-                 }
-                 break;
-
-       case PTRACE_GETREGS: { /* Get all gp regs from the child. */
-               if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) {
-                       ret = -EIO;
-                       break;
-               }
-               for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
-                       __put_user(getreg(child, i), datap);
-                       datap++;
-               }
-               ret = 0;
-               break;
-       }
-
-       case PTRACE_SETREGS: { /* Set all gp regs in the child. */
-               unsigned long tmp;
-               if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) {
-                       ret = -EIO;
-                       break;
-               }
-               for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
-                       __get_user(tmp, datap);
-                       putreg(child, i, tmp);
-                       datap++;
-               }
-               ret = 0;
-               break;
-       }
-
-       case PTRACE_GETFPREGS: { /* Get the child FPU state. */
-               if (!access_ok(VERIFY_WRITE, datap,
-                              sizeof(struct user_i387_struct))) {
-                       ret = -EIO;
-                       break;
-               }
-               ret = 0;
-               if (!tsk_used_math(child))
-                       init_fpu(child);
-               get_fpregs((struct user_i387_struct __user *)data, child);
-               break;
-       }
-
-       case PTRACE_SETFPREGS: { /* Set the child FPU state. */
-               if (!access_ok(VERIFY_READ, datap,
-                              sizeof(struct user_i387_struct))) {
-                       ret = -EIO;
-                       break;
-               }
-               set_stopped_child_used_math(child);
-               set_fpregs(child, (struct user_i387_struct __user *)data);
-               ret = 0;
-               break;
-       }
-
-       case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
-               if (!access_ok(VERIFY_WRITE, datap,
-                              sizeof(struct user_fxsr_struct))) {
-                       ret = -EIO;
-                       break;
-               }
-               if (!tsk_used_math(child))
-                       init_fpu(child);
-               ret = get_fpxregs((struct user_fxsr_struct __user *)data, child);
-               break;
-       }
-
-       case PTRACE_SETFPXREGS: { /* Set the child extended FPU state. */
-               if (!access_ok(VERIFY_READ, datap,
-                              sizeof(struct user_fxsr_struct))) {
-                       ret = -EIO;
-                       break;
-               }
-               set_stopped_child_used_math(child);
-               ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
-               break;
-       }
-
-       case PTRACE_GET_THREAD_AREA:
-               if (addr < 0)
-                       return -EIO;
-               ret = do_get_thread_area(child, addr,
-                                        (struct user_desc __user *) data);
-               break;
-
-       case PTRACE_SET_THREAD_AREA:
-               if (addr < 0)
-                       return -EIO;
-               ret = do_set_thread_area(child, addr,
-                                        (struct user_desc __user *) data, 0);
-               break;
-
-       default:
-               ret = ptrace_request(child, request, addr, data);
-               break;
-       }
-
-       return ret;
-}
-
-void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
-{
-       struct siginfo info;
-
-       tsk->thread.trap_no = 1;
-       tsk->thread.error_code = error_code;
-
-       memset(&info, 0, sizeof(info));
-       info.si_signo = SIGTRAP;
-       info.si_code = TRAP_BRKPT;
-
-       /* User-mode ip? */
-       info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
-
-       /* Send us the fake SIGTRAP */
-       force_sig_info(SIGTRAP, &info, tsk);
-}
-
-/* notification of system call entry/exit
- * - triggered by current->work.syscall_trace
- */
-__attribute__((regparm(3)))
-int do_syscall_trace(struct pt_regs *regs, int entryexit)
-{
-       int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
-       /*
-        * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
-        * interception
-        */
-       int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
-       int ret = 0;
-
-       /* do the secure computing check first */
-       if (!entryexit)
-               secure_computing(regs->orig_ax);
-
-       if (unlikely(current->audit_context)) {
-               if (entryexit)
-                       audit_syscall_exit(AUDITSC_RESULT(regs->ax),
-                                               regs->ax);
-               /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
-                * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
-                * not used, entry.S will call us only on syscall exit, not
-                * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
-                * calling send_sigtrap() on syscall entry.
-                *
-                * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
-                * is_singlestep is false, despite his name, so we will still do
-                * the correct thing.
-                */
-               else if (is_singlestep)
-                       goto out;
-       }
-
-       if (!(current->ptrace & PT_PTRACED))
-               goto out;
-
-       /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
-        * and then is resumed with SYSEMU_SINGLESTEP, it will come in
-        * here. We have to check this and return */
-       if (is_sysemu && entryexit)
-               return 0;
-
-       /* Fake a debug trap */
-       if (is_singlestep)
-               send_sigtrap(current, regs, 0);
-
-       if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
-               goto out;
-
-       /* the 0x80 provides a way for the tracing parent to distinguish
-          between a syscall stop and SIGTRAP delivery */
-       /* Note that the debugger could change the result of test_thread_flag!*/
-       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;
-       }
-       ret = is_sysemu;
-out:
-       if (unlikely(current->audit_context) && !entryexit)
-               audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
-                                   regs->bx, regs->cx, regs->dx, regs->si);
-       if (ret == 0)
-               return 0;
-
-       regs->orig_ax = -1; /* force skip of syscall restarting */
-       if (unlikely(current->audit_context))
-               audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
-       return 1;
-}