8 files changed, 41 insertions, 100 deletions

diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig
index 983c859e40b7..45268b50c0c8 100644
--- a/arch/c6x/Kconfig
+++ b/arch/c6x/Kconfig
@@ -17,6 +17,7 @@ config C6X
         select OF
         select OF_EARLY_FLATTREE
         select GENERIC_CLOCKEVENTS
+        select GENERIC_KERNEL_THREAD
 
 config MMU
         def_bool n
diff --git a/arch/c6x/include/asm/processor.h b/arch/c6x/include/asm/processor.h
index c50af7ef1c96..b9eb3da7f278 100644
--- a/arch/c6x/include/asm/processor.h
+++ b/arch/c6x/include/asm/processor.h
@@ -92,8 +92,6 @@ static inline void release_thread(struct task_struct *dead_task)
 {
 }
 
-extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
 #define copy_segments(tsk, mm)          do { } while (0)
 #define release_segments(mm)            do { } while (0)
 
diff --git a/arch/c6x/include/asm/syscalls.h b/arch/c6x/include/asm/syscalls.h
index aed53da703c9..e7b8991dc07c 100644
--- a/arch/c6x/include/asm/syscalls.h
+++ b/arch/c6x/include/asm/syscalls.h
@@ -44,11 +44,6 @@ extern int sys_cache_sync(unsigned long s, unsigned long e);
 struct pt_regs;
 
 extern asmlinkage long sys_c6x_clone(struct pt_regs *regs);
-extern asmlinkage long sys_c6x_execve(const char __user *name,
-                                      const char __user *const __user *argv,
-                                      const char __user *const __user *envp,
-                                      struct pt_regs *regs);
-
 
 #include <asm-generic/syscalls.h>
 
diff --git a/arch/c6x/include/asm/thread_info.h b/arch/c6x/include/asm/thread_info.h
index 1710bcbb8d09..4c8dc562bd90 100644
--- a/arch/c6x/include/asm/thread_info.h
+++ b/arch/c6x/include/asm/thread_info.h
@@ -97,7 +97,6 @@ struct thread_info *current_thread_info(void)
 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
 #define TIF_RESTORE_SIGMASK     4       /* restore signal mask in do_signal() */
 
-#define TIF_POLLING_NRFLAG      16      /* true if polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE              17      /* OOM killer killed process */
 
 #define TIF_WORK_MASK           0x00007FFE /* work on irq/exception return */
diff --git a/arch/c6x/include/asm/unistd.h b/arch/c6x/include/asm/unistd.h
index ed2259043eec..4ff747d12dad 100644
--- a/arch/c6x/include/asm/unistd.h
+++ b/arch/c6x/include/asm/unistd.h
@@ -14,6 +14,9 @@
  *   more details.
  */
 
+#define __ARCH_WANT_KERNEL_EXECVE
+#define __ARCH_WANT_SYS_EXECVE
+
 /* Use the standard ABI for syscalls. */
 #include <asm-generic/unistd.h>
 
diff --git a/arch/c6x/kernel/asm-offsets.c b/arch/c6x/kernel/asm-offsets.c
index 759ad6d207b6..60f1e437745d 100644
--- a/arch/c6x/kernel/asm-offsets.c
+++ b/arch/c6x/kernel/asm-offsets.c
@@ -116,7 +116,6 @@ void foo(void)
         DEFINE(_TIF_NOTIFY_RESUME, (1<<TIF_NOTIFY_RESUME));
         DEFINE(_TIF_SIGPENDING, (1<<TIF_SIGPENDING));
         DEFINE(_TIF_NEED_RESCHED, (1<<TIF_NEED_RESCHED));
-        DEFINE(_TIF_POLLING_NRFLAG, (1<<TIF_POLLING_NRFLAG));
 
         DEFINE(_TIF_ALLWORK_MASK, TIF_ALLWORK_MASK);
         DEFINE(_TIF_WORK_MASK, TIF_WORK_MASK);
diff --git a/arch/c6x/kernel/entry.S b/arch/c6x/kernel/entry.S
index 30b37e5f4a61..5449c36018fe 100644
--- a/arch/c6x/kernel/entry.S
+++ b/arch/c6x/kernel/entry.S
@@ -400,6 +400,32 @@ ret_from_fork_2:
         STW     .D2T2   B0,*+SP(REGS_A4+8)
 ENDPROC(ret_from_fork)
 
+ENTRY(ret_from_kernel_thread)
+#ifdef CONFIG_C6X_BIG_KERNEL
+        MVKL    .S1     schedule_tail,A0
+        MVKH    .S1     schedule_tail,A0
+        B       .S2X    A0
+#else
+        B       .S2     schedule_tail
+#endif
+        LDW     .D2T2   *+SP(REGS_A0+8),B10 /* get fn  */
+        ADDKPC  .S2     0f,B3,3
+0:
+        B       .S2     B10                /* call fn */
+        LDW     .D2T1   *+SP(REGS_A1+8),A4 /* get arg */
+        MVKL    .S2     sys_exit,B11
+        MVKH    .S2     sys_exit,B11
+        ADDKPC  .S2     0f,B3,1
+0:
+        BNOP    .S2     B11,5   /* jump to sys_exit */
+ENDPROC(ret_from_kernel_thread)
+
+ENTRY(ret_from_kernel_execve)
+        GET_THREAD_INFO A12
+        BNOP    .S2     syscall_exit,4
+        ADD     .D2X    A4,-8,SP
+ENDPROC(ret_from_kernel_execve)
+
         ;;
         ;; These are the interrupt handlers, responsible for calling __do_IRQ()
         ;; int6 is used for syscalls (see _system_call entry)
@@ -593,13 +619,6 @@ ENTRY(sys_sigaltstack)
         NOP     4
 ENDPROC(sys_sigaltstack)
 
-        ;; kernel_execve
-ENTRY(kernel_execve)
-        MVK     .S2     __NR_execve,B0
-        SWE
-        BNOP    .S2     B3,5
-ENDPROC(kernel_execve)
-
         ;;
         ;; Special system calls
         ;; return address is in B3
@@ -628,29 +647,6 @@ ENTRY(sys_rt_sigreturn)
 #endif
 ENDPROC(sys_rt_sigreturn)
 
-ENTRY(sys_execve)
-        ADDAW   .D2     SP,2,B6         ; put regs addr in 4th parameter
-                                        ; & adjust regs stack addr
-        LDW     .D2T2   *+SP(REGS_B4+8),B4
-
-        ;; c6x_execve(char *name, char **argv,
-        ;;            char **envp, struct pt_regs *regs)
-#ifdef CONFIG_C6X_BIG_KERNEL
- ||     MVKL    .S1     sys_c6x_execve,A0
-        MVKH    .S1     sys_c6x_execve,A0
-        B       .S2X    A0
-#else
- ||     B       .S2     sys_c6x_execve
-#endif
-        STW     .D2T2   B3,*SP--[2]
-        ADDKPC  .S2     ret_from_c6x_execve,B3,3
-
-ret_from_c6x_execve:
-        LDW     .D2T2   *++SP[2],B3
-        NOP     4
-        BNOP    .S2     B3,5
-ENDPROC(sys_execve)
-
 ENTRY(sys_pread_c6x)
         MV      .D2X    A8,B7
 #ifdef CONFIG_C6X_BIG_KERNEL
diff --git a/arch/c6x/kernel/process.c b/arch/c6x/kernel/process.c
index 45e924a636a0..2770d9a9a84e 100644
--- a/arch/c6x/kernel/process.c
+++ b/arch/c6x/kernel/process.c
@@ -25,6 +25,7 @@ void	(*c6x_restart)(void);
 void    (*c6x_halt)(void);
 
 extern asmlinkage void ret_from_fork(void);
+extern asmlinkage void ret_from_kernel_thread(void);
 
 /*
  * power off function, if any
@@ -103,37 +104,6 @@ void machine_power_off(void)
         halt_loop();
 }
 
-static void kernel_thread_helper(int dummy, void *arg, int (*fn)(void *))
-{
-        do_exit(fn(arg));
-}
-
-/*
- * Create a kernel thread
- */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
-        struct pt_regs regs;
-
-        /*
-         * copy_thread sets a4 to zero (child return from fork)
-         * so we can't just set things up to directly return to
-         * fn.
-         */
-        memset(&regs, 0, sizeof(regs));
-        regs.b4 = (unsigned long) arg;
-        regs.a6 = (unsigned long) fn;
-        regs.pc = (unsigned long) kernel_thread_helper;
-        local_save_flags(regs.csr);
-        regs.csr |= 1;
-        regs.tsr = 5; /* Set GEE and GIE in TSR */
-
-        /* Ok, create the new process.. */
-        return do_fork(flags | CLONE_VM | CLONE_UNTRACED, -1, &regs,
-                       0, NULL, NULL);
-}
-EXPORT_SYMBOL(kernel_thread);
-
 void flush_thread(void)
 {
 }
@@ -191,22 +161,24 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
         childregs = task_pt_regs(p);
 
-        *childregs = *regs;
-        childregs->a4 = 0;
-
-        if (usp == -1)
+        if (!regs) {
                 /* case of  __kernel_thread: we return to supervisor space */
+                memset(childregs, 0, sizeof(struct pt_regs));
                 childregs->sp = (unsigned long)(childregs + 1);
-        else
+                p->thread.pc = (unsigned long) ret_from_kernel_thread;
+                childregs->a0 = usp;            /* function */
+                childregs->a1 = ustk_size;      /* argument */
+        } else {
                 /* Otherwise use the given stack */
+                *childregs = *regs;
                 childregs->sp = usp;
+                p->thread.pc = (unsigned long) ret_from_fork;
+        }
 
         /* Set usp/ksp */
         p->thread.usp = childregs->sp;
-        /* switch_to uses stack to save/restore 14 callee-saved regs */
         thread_saved_ksp(p) = (unsigned long)childregs - 8;
-        p->thread.pc = (unsigned int) ret_from_fork;
-        p->thread.wchan = (unsigned long) ret_from_fork;
+        p->thread.wchan = p->thread.pc;
 #ifdef __DSBT__
         {
                 unsigned long dp;
@@ -221,28 +193,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
         return 0;
 }
 
-/*
- * c6x_execve() executes a new program.
- */
-SYSCALL_DEFINE4(c6x_execve, const char __user *, name,
-                const char __user *const __user *, argv,
-                const char __user *const __user *, envp,
-                struct pt_regs *, regs)
-{
-        int error;
-        char *filename;
-
-        filename = getname(name);
-        error = PTR_ERR(filename);
-        if (IS_ERR(filename))
-                goto out;
-
-        error = do_execve(filename, argv, envp, regs);
-        putname(filename);
-out:
-        return error;
-}
-
 unsigned long get_wchan(struct task_struct *p)
 {
         return p->thread.wchan;