Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

Pull pile 2 of execve and kernel_thread unification work from Al Viro:
 "Stuff in there: kernel_thread/kernel_execve/sys_execve conversions for
  several more architectures plus assorted signal fixes and cleanups.

  There'll be more (in particular, real fixes for the alpha
  do_notify_resume() irq mess)..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (43 commits)
  alpha: don't open-code trace_report_syscall_{enter,exit}
  Uninclude linux/freezer.h
  m32r: trim masks
  avr32: trim masks
  tile: don't bother with SIGTRAP in setup_frame
  microblaze: don't bother with SIGTRAP in setup_rt_frame()
  mn10300: don't bother with SIGTRAP in setup_frame()
  frv: no need to raise SIGTRAP in setup_frame()
  x86: get rid of duplicate code in case of CONFIG_VM86
  unicore32: remove pointless test
  h8300: trim _TIF_WORK_MASK
  parisc: decide whether to go to slow path (tracesys) based on thread flags
  parisc: don't bother looping in do_signal()
  parisc: fix double restarts
  bury the rest of TIF_IRET
  sanitize tsk_is_polling()
  bury _TIF_RESTORE_SIGMASK
  unicore32: unobfuscate _TIF_WORK_MASK
  mips: NOTIFY_RESUME is not needed in TIF masks
  mips: merge the identical "return from syscall" per-ABI code
  ...

Conflicts:
	arch/arm/include/asm/thread_info.h

7 files changed, 57 insertions, 110 deletions

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index dae1e7e16a37..76fd6e2f71da 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -15,6 +15,7 @@ config M68K
         select FPU if MMU
         select ARCH_WANT_IPC_PARSE_VERSION
         select ARCH_USES_GETTIMEOFFSET if MMU && !COLDFIRE
+        select GENERIC_KERNEL_THREAD
 
 config RWSEM_GENERIC_SPINLOCK
         bool
diff --git a/arch/m68k/include/asm/processor.h b/arch/m68k/include/asm/processor.h
index f17c42aff7ff..ae700f49e51d 100644
--- a/arch/m68k/include/asm/processor.h
+++ b/arch/m68k/include/asm/processor.h
@@ -100,6 +100,16 @@ struct thread_struct {
         .fs     = __KERNEL_DS,                                          \
 }
 
+/*
+ * ColdFire stack format sbould be 0x4 for an aligned usp (will always be
+ * true on thread creation). We need to set this explicitly.
+ */
+#ifdef CONFIG_COLDFIRE
+#define setframeformat(_regs)   do { (_regs)->format = 0x4; } while(0)
+#else
+#define setframeformat(_regs)   do { } while (0)
+#endif
+
 #ifdef CONFIG_MMU
 /*
  * Do necessary setup to start up a newly executed thread.
@@ -109,6 +119,7 @@ static inline void start_thread(struct pt_regs * regs, unsigned long pc,
 {
         regs->pc = pc;
         regs->sr &= ~0x2000;
+        setframeformat(regs);
         wrusp(usp);
 }
 
@@ -116,21 +127,11 @@ extern int handle_kernel_fault(struct pt_regs *regs);
 
 #else
 
-/*
- * Coldfire stacks need to be re-aligned on trap exit, conventional
- * 68k can handle this case cleanly.
- */
-#ifdef CONFIG_COLDFIRE
-#define reformat(_regs)         do { (_regs)->format = 0x4; } while(0)
-#else
-#define reformat(_regs)         do { } while (0)
-#endif
-
 #define start_thread(_regs, _pc, _usp)                  \
 do {                                                    \
         (_regs)->pc = (_pc);                            \
         ((struct switch_stack *)(_regs))[-1].a6 = 0;    \
-        reformat(_regs);                                \
+        setframeformat(_regs);                          \
         if (current->mm)                                \
                 (_regs)->d5 = current->mm->start_data;  \
         (_regs)->sr &= ~0x2000;                         \
@@ -153,8 +154,6 @@ static inline void release_thread(struct task_struct *dead_task)
 {
 }
 
-extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
 /*
  * Free current thread data structures etc..
  */
diff --git a/arch/m68k/include/asm/ptrace.h b/arch/m68k/include/asm/ptrace.h
index 65322b17b6cf..5e08b597f012 100644
--- a/arch/m68k/include/asm/ptrace.h
+++ b/arch/m68k/include/asm/ptrace.h
@@ -85,6 +85,8 @@ struct switch_stack {
 #define user_mode(regs) (!((regs)->sr & PS_S))
 #define instruction_pointer(regs) ((regs)->pc)
 #define profile_pc(regs) instruction_pointer(regs)
+#define current_pt_regs() \
+        (struct pt_regs *)((char *)current_thread_info() + THREAD_SIZE) - 1
 
 #define arch_has_single_step()  (1)
 
diff --git a/arch/m68k/include/asm/unistd.h b/arch/m68k/include/asm/unistd.h
index 045cfd6a9e31..c702ad716791 100644
--- a/arch/m68k/include/asm/unistd.h
+++ b/arch/m68k/include/asm/unistd.h
@@ -382,6 +382,8 @@
 #define __ARCH_WANT_SYS_SIGPROCMASK
 #define __ARCH_WANT_SYS_RT_SIGACTION
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
+#define __ARCH_WANT_SYS_EXECVE
+#define __ARCH_WANT_KERNEL_EXECVE
 
 /*
  * "Conditional" syscalls
diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index 165ee9f9d5c9..946cb0187751 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -111,6 +111,22 @@ ENTRY(ret_from_fork)
         addql   #4,%sp
         jra     ret_from_exception
 
+ENTRY(ret_from_kernel_thread)
+        | a3 contains the kernel thread payload, d7 - its argument
+        movel   %d1,%sp@-
+        jsr     schedule_tail
+        GET_CURRENT(%d0)
+        movel   %d7,(%sp)
+        jsr     %a3@
+        addql   #4,%sp
+        movel   %d0,(%sp)
+        jra     sys_exit
+
+ENTRY(ret_from_kernel_execve)
+        movel   4(%sp), %sp
+        GET_CURRENT(%d0)
+        jra     ret_from_exception
+
 #if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)
 
 #ifdef TRAP_DBG_INTERRUPT
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c
index ac2892e49c7c..c51bb172e14d 100644
--- a/arch/m68k/kernel/process.c
+++ b/arch/m68k/kernel/process.c
@@ -35,6 +35,7 @@
 
 
 asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
 
 
 /*
@@ -123,51 +124,6 @@ void show_regs(struct pt_regs * regs)
                 printk("USP: %08lx\n", rdusp());
 }
 
-/*
- * Create a kernel thread
- */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
-        int pid;
-        mm_segment_t fs;
-
-        fs = get_fs();
-        set_fs (KERNEL_DS);
-
-        {
-        register long retval __asm__ ("d0");
-        register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;
-
-        retval = __NR_clone;
-        __asm__ __volatile__
-          ("clrl %%d2\n\t"
-           "trap #0\n\t"                /* Linux/m68k system call */
-           "tstl %0\n\t"                /* child or parent */
-           "jne 1f\n\t"                 /* parent - jump */
-#ifdef CONFIG_MMU
-           "lea %%sp@(%c7),%6\n\t"      /* reload current */
-           "movel %6@,%6\n\t"
-#endif
-           "movel %3,%%sp@-\n\t"        /* push argument */
-           "jsr %4@\n\t"                /* call fn */
-           "movel %0,%%d1\n\t"          /* pass exit value */
-           "movel %2,%%d0\n\t"          /* exit */
-           "trap #0\n"
-           "1:"
-           : "+d" (retval)
-           : "i" (__NR_clone), "i" (__NR_exit),
-             "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
-             "i" (-THREAD_SIZE)
-           : "d2");
-
-        pid = retval;
-        }
-
-        set_fs (fs);
-        return pid;
-}
-EXPORT_SYMBOL(kernel_thread);
-
 void flush_thread(void)
 {
         current->thread.fs = __USER_DS;
@@ -219,30 +175,18 @@ asmlinkage int m68k_clone(struct pt_regs *regs)
 }
 
 int copy_thread(unsigned long clone_flags, unsigned long usp,
-                 unsigned long unused,
+                 unsigned long arg,
                  struct task_struct * p, struct pt_regs * regs)
 {
         struct pt_regs * childregs;
-        struct switch_stack * childstack, *stack;
-        unsigned long *retp;
+        struct switch_stack *childstack;
 
         childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
-
-        *childregs = *regs;
-        childregs->d0 = 0;
-
-        retp = ((unsigned long *) regs);
-        stack = ((struct switch_stack *) retp) - 1;
-
         childstack = ((struct switch_stack *) childregs) - 1;
-        *childstack = *stack;
-        childstack->retpc = (unsigned long)ret_from_fork;
 
         p->thread.usp = usp;
         p->thread.ksp = (unsigned long)childstack;
-
-        if (clone_flags & CLONE_SETTLS)
-                task_thread_info(p)->tp_value = regs->d5;
+        p->thread.esp0 = (unsigned long)childregs;
 
         /*
          * Must save the current SFC/DFC value, NOT the value when
@@ -250,6 +194,26 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
          */
         p->thread.fs = get_fs().seg;
 
+        if (unlikely(!regs)) {
+                /* kernel thread */
+                memset(childstack, 0,
+                        sizeof(struct switch_stack) + sizeof(struct pt_regs));
+                childregs->sr = PS_S;
+                childstack->a3 = usp; /* function */
+                childstack->d7 = arg;
+                childstack->retpc = (unsigned long)ret_from_kernel_thread;
+                p->thread.usp = 0;
+                return 0;
+        }
+        *childregs = *regs;
+        childregs->d0 = 0;
+
+        *childstack = ((struct switch_stack *) regs)[-1];
+        childstack->retpc = (unsigned long)ret_from_fork;
+
+        if (clone_flags & CLONE_SETTLS)
+                task_thread_info(p)->tp_value = regs->d5;
+
 #ifdef CONFIG_FPU
         if (!FPU_IS_EMU) {
                 /* Copy the current fpu state */
@@ -337,26 +301,6 @@ int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
 EXPORT_SYMBOL(dump_fpu);
 #endif /* CONFIG_FPU */
 
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage int sys_execve(const char __user *name,
-                          const char __user *const __user *argv,
-                          const char __user *const __user *envp)
-{
-        int error;
-        char * filename;
-        struct pt_regs *regs = (struct pt_regs *) &name;
-
-        filename = getname(name);
-        error = PTR_ERR(filename);
-        if (IS_ERR(filename))
-                return error;
-        error = do_execve(filename, argv, envp, regs);
-        putname(filename);
-        return error;
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
         unsigned long fp, pc;
diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c
index 9a5932ec3689..3a480b3df0d6 100644
--- a/arch/m68k/kernel/sys_m68k.c
+++ b/arch/m68k/kernel/sys_m68k.c
@@ -549,23 +549,6 @@ asmlinkage int sys_getpagesize(void)
         return PAGE_SIZE;
 }
 
-/*
- * Do a system call from kernel instead of calling sys_execve so we
- * end up with proper pt_regs.
- */
-int kernel_execve(const char *filename,
-                  const char *const argv[],
-                  const char *const envp[])
-{
-        register long __res asm ("%d0") = __NR_execve;
-        register long __a asm ("%d1") = (long)(filename);
-        register long __b asm ("%d2") = (long)(argv);
-        register long __c asm ("%d3") = (long)(envp);
-        asm volatile ("trap  #0" : "+d" (__res)
-                        : "d" (__a), "d" (__b), "d" (__c));
-        return __res;
-}
-
 asmlinkage unsigned long sys_get_thread_area(void)
 {
         return current_thread_info()->tp_value;