11 files changed, 39 insertions, 120 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index dba9390d37cf..4183e62f178c 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -40,6 +40,8 @@ config MIPS
         select HAVE_MOD_ARCH_SPECIFIC
         select MODULES_USE_ELF_REL
         select MODULES_USE_ELF_RELA if 64BIT
+        select GENERIC_KERNEL_THREAD
+        select GENERIC_KERNEL_EXECVE
 
 menu "Machine selection"
 
diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h
index 5e33fabe354d..d28c41e0887c 100644
--- a/arch/mips/include/asm/processor.h
+++ b/arch/mips/include/asm/processor.h
@@ -310,8 +310,6 @@ struct task_struct;
 /* Free all resources held by a thread. */
 #define release_thread(thread) do { } while(0)
 
-extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
-
 extern unsigned long thread_saved_pc(struct task_struct *tsk);
 
 /*
diff --git a/arch/mips/include/asm/ptrace.h b/arch/mips/include/asm/ptrace.h
index 4f5da948a777..cec5e125f7e4 100644
--- a/arch/mips/include/asm/ptrace.h
+++ b/arch/mips/include/asm/ptrace.h
@@ -61,4 +61,10 @@ static inline void die_if_kernel(const char *str, struct pt_regs *regs)
                 die(str, regs);
 }
 
+#define current_pt_regs()                                               \
+({                                                                      \
+        unsigned long sp = (unsigned long)__builtin_frame_address(0);   \
+        (struct pt_regs *)((sp | (THREAD_SIZE - 1)) + 1 - 32) - 1;      \
+})
+
 #endif /* _ASM_PTRACE_H */
diff --git a/arch/mips/include/asm/unistd.h b/arch/mips/include/asm/unistd.h
index 9e47cc11aa26..b306e2081cad 100644
--- a/arch/mips/include/asm/unistd.h
+++ b/arch/mips/include/asm/unistd.h
@@ -20,6 +20,7 @@
 #define __ARCH_OMIT_COMPAT_SYS_GETDENTS64
 #define __ARCH_WANT_OLD_READDIR
 #define __ARCH_WANT_SYS_ALARM
+#define __ARCH_WANT_SYS_EXECVE
 #define __ARCH_WANT_SYS_GETHOSTNAME
 #define __ARCH_WANT_SYS_IPC
 #define __ARCH_WANT_SYS_PAUSE
diff --git a/arch/mips/kernel/entry.S b/arch/mips/kernel/entry.S
index a6c133212003..3320cb4ac1d4 100644
--- a/arch/mips/kernel/entry.S
+++ b/arch/mips/kernel/entry.S
@@ -65,6 +65,12 @@ need_resched:
         b       need_resched
 #endif
 
+FEXPORT(ret_from_kernel_thread)
+        jal     schedule_tail           # a0 = struct task_struct *prev
+        move    a0, s1
+        jal     s0
+        j       syscall_exit
+
 FEXPORT(ret_from_fork)
         jal     schedule_tail           # a0 = struct task_struct *prev
 
diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c
index 3a21acedf882..8796dbc7e358 100644
--- a/arch/mips/kernel/linux32.c
+++ b/arch/mips/kernel/linux32.c
@@ -3,7 +3,6 @@
  *
  * Copyright (C) 2000 Silicon Graphics, Inc.
  * Written by Ulf Carlsson (ulfc@engr.sgi.com)
- * sys32_execve from ia64/ia32 code, Feb 2000, Kanoj Sarcar (kanoj@sgi.com)
  */
 #include <linux/compiler.h>
 #include <linux/mm.h>
@@ -77,26 +76,6 @@ out:
         return error;
 }
 
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage int sys32_execve(nabi_no_regargs struct pt_regs regs)
-{
-        int error;
-        struct filename *filename;
-
-        filename = getname(compat_ptr(regs.regs[4]));
-        error = PTR_ERR(filename);
-        if (IS_ERR(filename))
-                goto out;
-        error = compat_do_execve(filename->name, compat_ptr(regs.regs[5]),
-                                 compat_ptr(regs.regs[6]), &regs);
-        putname(filename);
-
-out:
-        return error;
-}
-
 #define RLIM_INFINITY32 0x7fffffff
 #define RESOURCE32(x) ((x > RLIM_INFINITY32) ? RLIM_INFINITY32 : x)
 
diff --git a/arch/mips/kernel/mips_ksyms.c b/arch/mips/kernel/mips_ksyms.c
index 3fc1691110dc..2d9304c2b54c 100644
--- a/arch/mips/kernel/mips_ksyms.c
+++ b/arch/mips/kernel/mips_ksyms.c
@@ -32,8 +32,6 @@ EXPORT_SYMBOL(memset);
 EXPORT_SYMBOL(memcpy);
 EXPORT_SYMBOL(memmove);
 
-EXPORT_SYMBOL(kernel_thread);
-
 /*
  * Functions that operate on entire pages.  Mostly used by memory management.
  */
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index e9a5fd7277f4..d13720ac656f 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -84,6 +84,7 @@ void __noreturn cpu_idle(void)
 }
 
 asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
 
 void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
 {
@@ -113,7 +114,7 @@ void flush_thread(void)
 }
 
 int copy_thread(unsigned long clone_flags, unsigned long usp,
-        unsigned long unused, struct task_struct *p, struct pt_regs *regs)
+        unsigned long arg, struct task_struct *p, struct pt_regs *regs)
 {
         struct thread_info *ti = task_thread_info(p);
         struct pt_regs *childregs;
@@ -136,19 +137,30 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
         childregs = (struct pt_regs *) childksp - 1;
         /*  Put the stack after the struct pt_regs.  */
         childksp = (unsigned long) childregs;
+        p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
+        if (unlikely(p->flags & PF_KTHREAD)) {
+                unsigned long status = p->thread.cp0_status;
+                memset(childregs, 0, sizeof(struct pt_regs));
+                ti->addr_limit = KERNEL_DS;
+                p->thread.reg16 = usp; /* fn */
+                p->thread.reg17 = arg;
+                p->thread.reg29 = childksp;
+                p->thread.reg31 = (unsigned long) ret_from_kernel_thread;
+#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
+                status = (status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) |
+                         ((status & (ST0_KUC | ST0_IEC)) << 2);
+#else
+                status |= ST0_EXL;
+#endif
+                childregs->cp0_status = status;
+                return 0;
+        }
         *childregs = *regs;
         childregs->regs[7] = 0; /* Clear error flag */
-
         childregs->regs[2] = 0; /* Child gets zero as return value */
+        childregs->regs[29] = usp;
+        ti->addr_limit = USER_DS;
 
-        if (childregs->cp0_status & ST0_CU0) {
-                childregs->regs[28] = (unsigned long) ti;
-                childregs->regs[29] = childksp;
-                ti->addr_limit = KERNEL_DS;
-        } else {
-                childregs->regs[29] = usp;
-                ti->addr_limit = USER_DS;
-        }
         p->thread.reg29 = (unsigned long) childregs;
         p->thread.reg31 = (unsigned long) ret_from_fork;
 
@@ -156,7 +168,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
          * New tasks lose permission to use the fpu. This accelerates context
          * switching for most programs since they don't use the fpu.
          */
-        p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
         childregs->cp0_status &= ~(ST0_CU2|ST0_CU1);
 
 #ifdef CONFIG_MIPS_MT_SMTC
@@ -222,35 +233,6 @@ int dump_task_fpu(struct task_struct *t, elf_fpregset_t *fpr)
 }
 
 /*
- * Create a kernel thread
- */
-static void __noreturn kernel_thread_helper(void *arg, int (*fn)(void *))
-{
-        do_exit(fn(arg));
-}
-
-long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
-{
-        struct pt_regs regs;
-
-        memset(&regs, 0, sizeof(regs));
-
-        regs.regs[4] = (unsigned long) arg;
-        regs.regs[5] = (unsigned long) fn;
-        regs.cp0_epc = (unsigned long) kernel_thread_helper;
-        regs.cp0_status = read_c0_status();
-#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
-        regs.cp0_status = (regs.cp0_status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) |
-                          ((regs.cp0_status & (ST0_KUC | ST0_IEC)) << 2);
-#else
-        regs.cp0_status |= ST0_EXL;
-#endif
-
-        /* Ok, create the new process.. */
-        return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
-}
-
-/*
  *
  */
 struct mips_frame_info {
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index f6ba8381ee01..d27ca340d46d 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -167,7 +167,7 @@ EXPORT(sysn32_call_table)
         PTR     sys_getsockopt
         PTR     sys_clone                       /* 6055 */
         PTR     sys_fork
-        PTR     sys32_execve
+        PTR     compat_sys_execve
         PTR     sys_exit
         PTR     compat_sys_wait4
         PTR     sys_kill                        /* 6060 */
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index 53c2d7245764..9601be6afa3d 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -203,7 +203,7 @@ sys_call_table:
         PTR     sys_creat
         PTR     sys_link
         PTR     sys_unlink                      /* 4010 */
-        PTR     sys32_execve
+        PTR     compat_sys_execve
         PTR     sys_chdir
         PTR     compat_sys_time
         PTR     sys_mknod
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index 2bd561bc05ae..c611e2df7767 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -127,28 +127,6 @@ _sys_clone(nabi_no_regargs struct pt_regs regs)
                        parent_tidptr, child_tidptr);
 }
 
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
-{
-        int error;
-        struct filename *filename;
-
-        filename = getname((const char __user *) (long)regs.regs[4]);
-        error = PTR_ERR(filename);
-        if (IS_ERR(filename))
-                goto out;
-        error = do_execve(filename->name,
-                          (const char __user *const __user *) (long)regs.regs[5],
-                          (const char __user *const __user *) (long)regs.regs[6],
-                          &regs);
-        putname(filename);
-
-out:
-        return error;
-}
-
 SYSCALL_DEFINE1(set_thread_area, unsigned long, addr)
 {
         struct thread_info *ti = task_thread_info(current);
@@ -313,34 +291,3 @@ asmlinkage void bad_stack(void)
 {
         do_exit(SIGSEGV);
 }
-
-/*
- * 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 unsigned long __a0 asm("$4") = (unsigned long) filename;
-        register unsigned long __a1 asm("$5") = (unsigned long) argv;
-        register unsigned long __a2 asm("$6") = (unsigned long) envp;
-        register unsigned long __a3 asm("$7");
-        unsigned long __v0;
-
-        __asm__ volatile ("                                     \n"
-        "       .set    noreorder                               \n"
-        "       li      $2, %5          # __NR_execve           \n"
-        "       syscall                                         \n"
-        "       move    %0, $2                                  \n"
-        "       .set    reorder                                 \n"
-        : "=&r" (__v0), "=r" (__a3)
-        : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
-        : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
-          "memory");
-
-        if (__a3 == 0)
-                return __v0;
-
-        return -__v0;
-}