vserver 1.9.3

[linux-2.6.git] / arch / s390 / kernel / process.c

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 73cb6ba..5d56e77 100644 (file)
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -58,14 +58,11 @@ asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
  */
 unsigned long thread_saved_pc(struct task_struct *tsk)
 {
-       unsigned long bc;
+       struct stack_frame *sf;
 
-       bc = *((unsigned long *) tsk->thread.ksp);
-#ifndef CONFIG_ARCH_S390X
-       return *((unsigned long *) (bc+56));
-#else
-       return *((unsigned long *) (bc+112));
-#endif
+       sf = (struct stack_frame *) tsk->thread.ksp;
+       sf = (struct stack_frame *) sf->back_chain;
+       return sf->gprs[8];
 }
 
 /*
@@ -186,41 +183,20 @@ void show_regs(struct pt_regs *regs)
 
 extern void kernel_thread_starter(void);
 
-#ifndef CONFIG_ARCH_S390X
-
 __asm__(".align 4\n"
        "kernel_thread_starter:\n"
-       "    l     15,0(8)\n"
-       "    sr    15,7\n"
-       "    stosm 24(15),3\n"
-       "    lr    2,10\n"
+       "    la    2,0(10)\n"
        "    basr  14,9\n"
-       "    sr    2,2\n"
+       "    la    2,0\n"
        "    br    11\n");
 
-#else /* CONFIG_ARCH_S390X */
-
-__asm__(".align 4\n"
-       "kernel_thread_starter:\n"
-       "    lg    15,0(8)\n"
-       "    sgr   15,7\n"
-       "    stosm 48(15),3\n"
-       "    lgr   2,10\n"
-       "    basr  14,9\n"
-       "    sgr   2,2\n"
-       "    br    11\n");
-
-#endif /* CONFIG_ARCH_S390X */
-
 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
 {
        struct pt_regs regs;
 
        memset(&regs, 0, sizeof(regs));
-       regs.psw.mask = PSW_KERNEL_BITS;
+       regs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
        regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
-       regs.gprs[7] = STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
-       regs.gprs[8] = __LC_KERNEL_STACK;
        regs.gprs[9] = (unsigned long) fn;
        regs.gprs[10] = (unsigned long) arg;
        regs.gprs[11] = (unsigned long) do_exit;
@@ -253,20 +229,13 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,
        unsigned long unused,
         struct task_struct * p, struct pt_regs * regs)
 {
-        struct stack_frame
+        struct fake_frame
           {
-            unsigned long back_chain;
-            unsigned long eos;
-            unsigned long glue1;
-            unsigned long glue2;
-            unsigned long scratch[2];
-            unsigned long gprs[10];    /* gprs 6 -15                       */
-            unsigned int  fprs[4];     /* fpr 4 and 6                      */
-            unsigned int  empty[4];
+           struct stack_frame sf;
             struct pt_regs childregs;
           } *frame;
 
-        frame = ((struct stack_frame *)
+        frame = ((struct fake_frame *)
                 (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
         p->thread.ksp = (unsigned long) frame;
        p->set_child_tid = p->clear_child_tid = NULL;
@@ -274,13 +243,13 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp,
         frame->childregs = *regs;
        frame->childregs.gprs[2] = 0;   /* child returns 0 on fork. */
         frame->childregs.gprs[15] = new_stackp;
-        frame->back_chain = frame->eos = 0;
+        frame->sf.back_chain = 0;
 
         /* new return point is ret_from_fork */
-        frame->gprs[8] = (unsigned long) ret_from_fork;
+        frame->sf.gprs[8] = (unsigned long) ret_from_fork;
 
         /* fake return stack for resume(), don't go back to schedule */
-        frame->gprs[9] = (unsigned long) frame;
+        frame->sf.gprs[9] = (unsigned long) frame;
 
        /* Save access registers to new thread structure. */
        save_access_regs(&p->thread.acrs[0]);
@@ -336,7 +305,7 @@ asmlinkage long sys_clone(struct pt_regs regs)
        child_tidptr = (int __user *) regs.gprs[5];
         if (!newsp)
                 newsp = regs.gprs[15];
-        return do_fork(clone_flags & ~CLONE_IDLETASK, newsp, &regs, 0,
+        return do_fork(clone_flags, newsp, &regs, 0,
                       parent_tidptr, child_tidptr);
 }
 
@@ -423,30 +392,26 @@ void dump_thread(struct pt_regs * regs, struct user * dump)
 
 unsigned long get_wchan(struct task_struct *p)
 {
-       unsigned long r14, r15, bc;
-       unsigned long stack_page;
-       int count = 0;
-       if (!p || p == current || p->state == TASK_RUNNING)
+       struct stack_frame *sf, *low, *high;
+       unsigned long return_address;
+       int count;
+
+       if (!p || p == current || p->state == TASK_RUNNING || !p->thread_info)
                return 0;
-       stack_page = (unsigned long) p->thread_info;
-       r15 = p->thread.ksp;
-       if (!stack_page || r15 < stack_page ||
-           r15 >= THREAD_SIZE - sizeof(unsigned long) + stack_page)
+       low = (struct stack_frame *) p->thread_info;
+       high = (struct stack_frame *)
+               ((unsigned long) p->thread_info + THREAD_SIZE) - 1;
+       sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN);
+       if (sf <= low || sf > high)
                return 0;
-       bc = (*(unsigned long *) r15) & PSW_ADDR_INSN;
-       do {
-               if (bc < stack_page ||
-                   bc >= THREAD_SIZE - sizeof(unsigned long) + stack_page)
+       for (count = 0; count < 16; count++) {
+               sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN);
+               if (sf <= low || sf > high)
                        return 0;
-#ifndef CONFIG_ARCH_S390X
-               r14 = (*(unsigned long *) (bc+56)) & PSW_ADDR_INSN;
-#else
-               r14 = *(unsigned long *) (bc+112);
-#endif
-               if (!in_sched_functions(r14))
-                       return r14;
-               bc = (*(unsigned long *) bc) & PSW_ADDR_INSN;
-       } while (count++ < 16);
+               return_address = sf->gprs[8] & PSW_ADDR_INSN;
+               if (!in_sched_functions(return_address))
+                       return return_address;
+       }
        return 0;
 }