]> err.no Git - linux-2.6/blobdiff - arch/ia64/kernel/ptrace.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6.25
[linux-2.6] / arch / ia64 / kernel / ptrace.c
index 9d2591423eb7dd0ae987aa5a3529e66ece4549e5..ab784ec4319dbd2eea568a5a6cbc566e829eb358 100644 (file)
@@ -697,52 +697,6 @@ thread_matches (struct task_struct *thread, unsigned long addr)
        return 1;       /* looks like we've got a winner */
 }
 
-/*
- * GDB apparently wants to be able to read the register-backing store
- * of any thread when attached to a given process.  If we are peeking
- * or poking an address that happens to reside in the kernel-backing
- * store of another thread, we need to attach to that thread, because
- * otherwise we end up accessing stale data.
- *
- * task_list_lock must be read-locked before calling this routine!
- */
-static struct task_struct *
-find_thread_for_addr (struct task_struct *child, unsigned long addr)
-{
-       struct task_struct *p;
-       struct mm_struct *mm;
-       struct list_head *this, *next;
-       int mm_users;
-
-       if (!(mm = get_task_mm(child)))
-               return child;
-
-       /* -1 because of our get_task_mm(): */
-       mm_users = atomic_read(&mm->mm_users) - 1;
-       if (mm_users <= 1)
-               goto out;               /* not multi-threaded */
-
-       /*
-        * Traverse the current process' children list.  Every task that
-        * one attaches to becomes a child.  And it is only attached children
-        * of the debugger that are of interest (ptrace_check_attach checks
-        * for this).
-        */
-       list_for_each_safe(this, next, &current->children) {
-               p = list_entry(this, struct task_struct, sibling);
-               if (p->tgid != child->tgid)
-                       continue;
-               if (thread_matches(p, addr)) {
-                       child = p;
-                       goto out;
-               }
-       }
-
-  out:
-       mmput(mm);
-       return child;
-}
-
 /*
  * Write f32-f127 back to task->thread.fph if it has been modified.
  */
@@ -826,14 +780,14 @@ convert_to_non_syscall (struct task_struct *child, struct pt_regs  *pt,
                if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
                    < IA64_PT_REGS_SIZE) {
                        dprintk("ptrace.%s: ran off the top of the kernel "
-                               "stack\n", __FUNCTION__);
+                               "stack\n", __func__);
                        return;
                }
                if (unw_get_pr (&prev_info, &pr) < 0) {
                        unw_get_rp(&prev_info, &ip);
                        dprintk("ptrace.%s: failed to read "
                                "predicate register (ip=0x%lx)\n",
-                               __FUNCTION__, ip);
+                               __func__, ip);
                        return;
                }
                if (unw_is_intr_frame(&info)
@@ -1011,14 +965,9 @@ access_uarea (struct task_struct *child, unsigned long addr,
                         * the kernel was entered.
                         *
                         * Furthermore, when changing the contents of
-                        * PT_AR_BSP (or PT_CFM) we MUST copy any
-                        * users-level stacked registers that are
-                        * stored on the kernel stack back to
-                        * user-space because otherwise, we might end
-                        * up clobbering kernel stacked registers.
-                        * Also, if this happens while the task is
-                        * blocked in a system call, which convert the
-                        * state such that the non-system-call exit
+                        * PT_AR_BSP (or PT_CFM) while the task is
+                        * blocked in a system call, convert the state
+                        * so that the non-system-call exit
                         * path is used.  This ensures that the proper
                         * state will be picked up when resuming
                         * execution.  However, it *also* means that
@@ -1035,10 +984,6 @@ access_uarea (struct task_struct *child, unsigned long addr,
                        urbs_end = ia64_get_user_rbs_end(child, pt, &cfm);
                        if (write_access) {
                                if (*data != urbs_end) {
-                                       if (ia64_sync_user_rbs(child, sw,
-                                                              pt->ar_bspstore,
-                                                              urbs_end) < 0)
-                                               return -1;
                                        if (in_syscall(pt))
                                                convert_to_non_syscall(child,
                                                                       pt,
@@ -1058,10 +1003,6 @@ access_uarea (struct task_struct *child, unsigned long addr,
                        urbs_end = ia64_get_user_rbs_end(child, pt, &cfm);
                        if (write_access) {
                                if (((cfm ^ *data) & PFM_MASK) != 0) {
-                                       if (ia64_sync_user_rbs(child, sw,
-                                                              pt->ar_bspstore,
-                                                              urbs_end) < 0)
-                                               return -1;
                                        if (in_syscall(pt))
                                                convert_to_non_syscall(child,
                                                                       pt,
@@ -1513,207 +1454,97 @@ ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
        return ret;
 }
 
-/*
- * Called by kernel/ptrace.c when detaching..
- *
- * Make sure the single step bit is not set.
- */
 void
-ptrace_disable (struct task_struct *child)
+user_enable_single_step (struct task_struct *child)
 {
        struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
 
-       /* make sure the single step/taken-branch trap bits are not set: */
-       clear_tsk_thread_flag(child, TIF_SINGLESTEP);
-       child_psr->ss = 0;
-       child_psr->tb = 0;
+       set_tsk_thread_flag(child, TIF_SINGLESTEP);
+       child_psr->ss = 1;
 }
 
-asmlinkage long
-sys_ptrace (long request, pid_t pid, unsigned long addr, unsigned long data)
+void
+user_enable_block_step (struct task_struct *child)
 {
-       struct pt_regs *pt;
-       unsigned long peek_or_poke;
-       struct task_struct *child;
-       struct switch_stack *sw;
-       long ret;
+       struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
 
-       lock_kernel();
-       ret = -EPERM;
-       if (request == PTRACE_TRACEME) {
-               ret = ptrace_traceme();
-               goto out;
-       }
+       set_tsk_thread_flag(child, TIF_SINGLESTEP);
+       child_psr->tb = 1;
+}
 
-       peek_or_poke = (request == PTRACE_PEEKTEXT
-                       || request == PTRACE_PEEKDATA
-                       || request == PTRACE_POKETEXT
-                       || request == PTRACE_POKEDATA);
-       ret = -ESRCH;
-       read_lock(&tasklist_lock);
-       {
-               child = find_task_by_pid(pid);
-               if (child) {
-                       if (peek_or_poke)
-                               child = find_thread_for_addr(child, addr);
-                       get_task_struct(child);
-               }
-       }
-       read_unlock(&tasklist_lock);
-       if (!child)
-               goto out;
-       ret = -EPERM;
-       if (pid == 1)           /* no messing around with init! */
-               goto out_tsk;
-
-       if (request == PTRACE_ATTACH) {
-               ret = ptrace_attach(child);
-               if (!ret)
-                       arch_ptrace_attach(child);
-               goto out_tsk;
-       }
+void
+user_disable_single_step (struct task_struct *child)
+{
+       struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
 
-       ret = ptrace_check_attach(child, request == PTRACE_KILL);
-       if (ret < 0)
-               goto out_tsk;
+       /* make sure the single step/taken-branch trap bits are not set: */
+       clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+       child_psr->ss = 0;
+       child_psr->tb = 0;
+}
 
-       pt = task_pt_regs(child);
-       sw = (struct switch_stack *) (child->thread.ksp + 16);
+/*
+ * 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);
+}
 
+long
+arch_ptrace (struct task_struct *child, long request, long addr, long data)
+{
        switch (request) {
-             case PTRACE_PEEKTEXT:
-             case PTRACE_PEEKDATA:
+       case PTRACE_PEEKTEXT:
+       case PTRACE_PEEKDATA:
                /* read word at location addr */
                if (access_process_vm(child, addr, &data, sizeof(data), 0)
-                   != sizeof(data)) {
-                       ret = -EIO;
-                       goto out_tsk;
-               }
-               ret = data;
-               /* ensure "ret" is not mistaken as an error code */
+                   != sizeof(data))
+                       return -EIO;
+               /* ensure return value is not mistaken for error code */
                force_successful_syscall_return();
-               goto out_tsk;
+               return data;
 
        /* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
         * by the generic ptrace_request().
         */
 
-             case PTRACE_PEEKUSR:
+       case PTRACE_PEEKUSR:
                /* read the word at addr in the USER area */
-               if (access_uarea(child, addr, &data, 0) < 0) {
-                       ret = -EIO;
-                       goto out_tsk;
-               }
-               ret = data;
-               /* ensure "ret" is not mistaken as an error code */
+               if (access_uarea(child, addr, &data, 0) < 0)
+                       return -EIO;
+               /* ensure return value is not mistaken for error code */
                force_successful_syscall_return();
-               goto out_tsk;
+               return data;
 
-             case PTRACE_POKEUSR:
+       case PTRACE_POKEUSR:
                /* write the word at addr in the USER area */
-               if (access_uarea(child, addr, &data, 1) < 0) {
-                       ret = -EIO;
-                       goto out_tsk;
-               }
-               ret = 0;
-               goto out_tsk;
+               if (access_uarea(child, addr, &data, 1) < 0)
+                       return -EIO;
+               return 0;
 
-             case PTRACE_OLD_GETSIGINFO:
+       case PTRACE_OLD_GETSIGINFO:
                /* for backwards-compatibility */
-               ret = ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
-               goto out_tsk;
+               return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
 
-             case PTRACE_OLD_SETSIGINFO:
+       case PTRACE_OLD_SETSIGINFO:
                /* for backwards-compatibility */
-               ret = ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
-               goto out_tsk;
-
-             case PTRACE_SYSCALL:
-               /* continue and stop at next (return from) syscall */
-             case PTRACE_CONT:
-               /* restart after signal. */
-               ret = -EIO;
-               if (!valid_signal(data))
-                       goto out_tsk;
-               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;
+               return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
 
-               /*
-                * Make sure the single step/taken-branch trap bits
-                * are not set:
-                */
-               clear_tsk_thread_flag(child, TIF_SINGLESTEP);
-               ia64_psr(pt)->ss = 0;
-               ia64_psr(pt)->tb = 0;
+       case PTRACE_GETREGS:
+               return ptrace_getregs(child,
+                                     (struct pt_all_user_regs __user *) data);
 
-               wake_up_process(child);
-               ret = 0;
-               goto out_tsk;
+       case PTRACE_SETREGS:
+               return ptrace_setregs(child,
+                                     (struct pt_all_user_regs __user *) data);
 
-             case PTRACE_KILL:
-               /*
-                * 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.
-                */
-               if (child->exit_state == EXIT_ZOMBIE)
-                       /* already dead */
-                       goto out_tsk;
-               child->exit_code = SIGKILL;
-
-               ptrace_disable(child);
-               wake_up_process(child);
-               ret = 0;
-               goto out_tsk;
-
-             case PTRACE_SINGLESTEP:
-               /* let child execute for one instruction */
-             case PTRACE_SINGLEBLOCK:
-               ret = -EIO;
-               if (!valid_signal(data))
-                       goto out_tsk;
-
-               clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
-               set_tsk_thread_flag(child, TIF_SINGLESTEP);
-               if (request == PTRACE_SINGLESTEP) {
-                       ia64_psr(pt)->ss = 1;
-               } else {
-                       ia64_psr(pt)->tb = 1;
-               }
-               child->exit_code = data;
-
-               /* give it a chance to run. */
-               wake_up_process(child);
-               ret = 0;
-               goto out_tsk;
-
-             case PTRACE_DETACH:
-               /* detach a process that was attached. */
-               ret = ptrace_detach(child, data);
-               goto out_tsk;
-
-             case PTRACE_GETREGS:
-               ret = ptrace_getregs(child,
-                                    (struct pt_all_user_regs __user *) data);
-               goto out_tsk;
-
-             case PTRACE_SETREGS:
-               ret = ptrace_setregs(child,
-                                    (struct pt_all_user_regs __user *) data);
-               goto out_tsk;
-
-             default:
-               ret = ptrace_request(child, request, addr, data);
-               goto out_tsk;
+       default:
+               return ptrace_request(child, request, addr, data);
        }
-  out_tsk:
-       put_task_struct(child);
-  out:
-       unlock_kernel();
-       return ret;
 }