1 files changed, 777 insertions, 0 deletions

diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
new file mode 100644
index 00000000..3ee51f18
--- /dev/null
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -0,0 +1,777 @@
+/* linux/arch/sparc64/kernel/sys_sparc.c
+ *
+ * This file contains various random system calls that
+ * have a non-standard calling sequence on the Linux/sparc
+ * platform.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/mm.h>
+#include <linux/sem.h>
+#include <linux/msg.h>
+#include <linux/shm.h>
+#include <linux/stat.h>
+#include <linux/mman.h>
+#include <linux/utsname.h>
+#include <linux/smp.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/ipc.h>
+#include <linux/personality.h>
+#include <linux/random.h>
+#include <linux/export.h>
+
+#include <asm/uaccess.h>
+#include <asm/utrap.h>
+#include <asm/unistd.h>
+
+#include "entry.h"
+#include "systbls.h"
+
+/* #define DEBUG_UNIMP_SYSCALL */
+
+asmlinkage unsigned long sys_getpagesize(void)
+{
+	return PAGE_SIZE;
+}
+
+#define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL))
+#define VA_EXCLUDE_END   (0xfffff80000000000UL + (1UL << 32UL))
+
+/* Does addr --> addr+len fall within 4GB of the VA-space hole or
+ * overflow past the end of the 64-bit address space?
+ */
+static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
+{
+	unsigned long va_exclude_start, va_exclude_end;
+
+	va_exclude_start = VA_EXCLUDE_START;
+	va_exclude_end   = VA_EXCLUDE_END;
+
+	if (unlikely(len >= va_exclude_start))
+		return 1;
+
+	if (unlikely((addr + len) < addr))
+		return 1;
+
+	if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
+		     ((addr + len) >= va_exclude_start &&
+		      (addr + len) < va_exclude_end)))
+		return 1;
+
+	return 0;
+}
+
+/* Does start,end straddle the VA-space hole?  */
+static inline int straddles_64bit_va_hole(unsigned long start, unsigned long end)
+{
+	unsigned long va_exclude_start, va_exclude_end;
+
+	va_exclude_start = VA_EXCLUDE_START;
+	va_exclude_end   = VA_EXCLUDE_END;
+
+	if (likely(start < va_exclude_start && end < va_exclude_start))
+		return 0;
+
+	if (likely(start >= va_exclude_end && end >= va_exclude_end))
+		return 0;
+
+	return 1;
+}
+
+/* These functions differ from the default implementations in
+ * mm/mmap.c in two ways:
+ *
+ * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
+ *    for fixed such mappings we just validate what the user gave us.
+ * 2) For 64-bit tasks we avoid mapping anything within 4GB of
+ *    the spitfire/niagara VA-hole.
+ */
+
+static inline unsigned long COLOUR_ALIGN(unsigned long addr,
+					 unsigned long pgoff)
+{
+	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
+	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
+
+	return base + off;
+}
+
+static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr,
+					      unsigned long pgoff)
+{
+	unsigned long base = addr & ~(SHMLBA-1);
+	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
+
+	if (base + off <= addr)
+		return base + off;
+	return base - off;
+}
+
+unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct * vma;
+	unsigned long task_size = TASK_SIZE;
+	unsigned long start_addr;
+	int do_color_align;
+
+	if (flags & MAP_FIXED) {
+		/* We do not accept a shared mapping if it would violate
+		 * cache aliasing constraints.
+		 */
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
+			return -EINVAL;
+		return addr;
+	}
+
+	if (test_thread_flag(TIF_32BIT))
+		task_size = STACK_TOP32;
+	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
+		return -ENOMEM;
+
+	do_color_align = 0;
+	if (filp || (flags & MAP_SHARED))
+		do_color_align = 1;
+
+	if (addr) {
+		if (do_color_align)
+			addr = COLOUR_ALIGN(addr, pgoff);
+		else
+			addr = PAGE_ALIGN(addr);
+
+		vma = find_vma(mm, addr);
+		if (task_size - len >= addr &&
+		    (!vma || addr + len <= vma->vm_start))
+			return addr;
+	}
+
+	if (len > mm->cached_hole_size) {
+	        start_addr = addr = mm->free_area_cache;
+	} else {
+	        start_addr = addr = TASK_UNMAPPED_BASE;
+	        mm->cached_hole_size = 0;
+	}
+
+	task_size -= len;
+
+full_search:
+	if (do_color_align)
+		addr = COLOUR_ALIGN(addr, pgoff);
+	else
+		addr = PAGE_ALIGN(addr);
+
+	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+		/* At this point:  (!vma || addr < vma->vm_end). */
+		if (addr < VA_EXCLUDE_START &&
+		    (addr + len) >= VA_EXCLUDE_START) {
+			addr = VA_EXCLUDE_END;
+			vma = find_vma(mm, VA_EXCLUDE_END);
+		}
+		if (unlikely(task_size < addr)) {
+			if (start_addr != TASK_UNMAPPED_BASE) {
+				start_addr = addr = TASK_UNMAPPED_BASE;
+				mm->cached_hole_size = 0;
+				goto full_search;
+			}
+			return -ENOMEM;
+		}
+		if (likely(!vma || addr + len <= vma->vm_start)) {
+			/*
+			 * Remember the place where we stopped the search:
+			 */
+			mm->free_area_cache = addr + len;
+			return addr;
+		}
+		if (addr + mm->cached_hole_size < vma->vm_start)
+		        mm->cached_hole_size = vma->vm_start - addr;
+
+		addr = vma->vm_end;
+		if (do_color_align)
+			addr = COLOUR_ALIGN(addr, pgoff);
+	}
+}
+
+unsigned long
+arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
+			  const unsigned long len, const unsigned long pgoff,
+			  const unsigned long flags)
+{
+	struct vm_area_struct *vma;
+	struct mm_struct *mm = current->mm;
+	unsigned long task_size = STACK_TOP32;
+	unsigned long addr = addr0;
+	int do_color_align;
+
+	/* This should only ever run for 32-bit processes.  */
+	BUG_ON(!test_thread_flag(TIF_32BIT));
+
+	if (flags & MAP_FIXED) {
+		/* We do not accept a shared mapping if it would violate
+		 * cache aliasing constraints.
+		 */
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
+			return -EINVAL;
+		return addr;
+	}
+
+	if (unlikely(len > task_size))
+		return -ENOMEM;
+
+	do_color_align = 0;
+	if (filp || (flags & MAP_SHARED))
+		do_color_align = 1;
+
+	/* requesting a specific address */
+	if (addr) {
+		if (do_color_align)
+			addr = COLOUR_ALIGN(addr, pgoff);
+		else
+			addr = PAGE_ALIGN(addr);
+
+		vma = find_vma(mm, addr);
+		if (task_size - len >= addr &&
+		    (!vma || addr + len <= vma->vm_start))
+			return addr;
+	}
+
+	/* check if free_area_cache is useful for us */
+	if (len <= mm->cached_hole_size) {
+ 	        mm->cached_hole_size = 0;
+ 		mm->free_area_cache = mm->mmap_base;
+ 	}
+
+	/* either no address requested or can't fit in requested address hole */
+	addr = mm->free_area_cache;
+	if (do_color_align) {
+		unsigned long base = COLOUR_ALIGN_DOWN(addr-len, pgoff);
+
+		addr = base + len;
+	}
+
+	/* make sure it can fit in the remaining address space */
+	if (likely(addr > len)) {
+		vma = find_vma(mm, addr-len);
+		if (!vma || addr <= vma->vm_start) {
+			/* remember the address as a hint for next time */
+			return (mm->free_area_cache = addr-len);
+		}
+	}
+
+	if (unlikely(mm->mmap_base < len))
+		goto bottomup;
+
+	addr = mm->mmap_base-len;
+	if (do_color_align)
+		addr = COLOUR_ALIGN_DOWN(addr, pgoff);
+
+	do {
+		/*
+		 * Lookup failure means no vma is above this address,
+		 * else if new region fits below vma->vm_start,
+		 * return with success:
+		 */
+		vma = find_vma(mm, addr);
+		if (likely(!vma || addr+len <= vma->vm_start)) {
+			/* remember the address as a hint for next time */
+			return (mm->free_area_cache = addr);
+		}
+
+ 		/* remember the largest hole we saw so far */
+ 		if (addr + mm->cached_hole_size < vma->vm_start)
+ 		        mm->cached_hole_size = vma->vm_start - addr;
+
+		/* try just below the current vma->vm_start */
+		addr = vma->vm_start-len;
+		if (do_color_align)
+			addr = COLOUR_ALIGN_DOWN(addr, pgoff);
+	} while (likely(len < vma->vm_start));
+
+bottomup:
+	/*
+	 * A failed mmap() very likely causes application failure,
+	 * so fall back to the bottom-up function here. This scenario
+	 * can happen with large stack limits and large mmap()
+	 * allocations.
+	 */
+	mm->cached_hole_size = ~0UL;
+  	mm->free_area_cache = TASK_UNMAPPED_BASE;
+	addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
+	/*
+	 * Restore the topdown base:
+	 */
+	mm->free_area_cache = mm->mmap_base;
+	mm->cached_hole_size = ~0UL;
+
+	return addr;
+}
+
+/* Try to align mapping such that we align it as much as possible. */
+unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+	unsigned long align_goal, addr = -ENOMEM;
+	unsigned long (*get_area)(struct file *, unsigned long,
+				  unsigned long, unsigned long, unsigned long);
+
+	get_area = current->mm->get_unmapped_area;
+
+	if (flags & MAP_FIXED) {
+		/* Ok, don't mess with it. */
+		return get_area(NULL, orig_addr, len, pgoff, flags);
+	}
+	flags &= ~MAP_SHARED;
+
+	align_goal = PAGE_SIZE;
+	if (len >= (4UL * 1024 * 1024))
+		align_goal = (4UL * 1024 * 1024);
+	else if (len >= (512UL * 1024))
+		align_goal = (512UL * 1024);
+	else if (len >= (64UL * 1024))
+		align_goal = (64UL * 1024);
+
+	do {
+		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
+		if (!(addr & ~PAGE_MASK)) {
+			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
+			break;
+		}
+
+		if (align_goal == (4UL * 1024 * 1024))
+			align_goal = (512UL * 1024);
+		else if (align_goal == (512UL * 1024))
+			align_goal = (64UL * 1024);
+		else
+			align_goal = PAGE_SIZE;
+	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
+
+	/* Mapping is smaller than 64K or larger areas could not
+	 * be obtained.
+	 */
+	if (addr & ~PAGE_MASK)
+		addr = get_area(NULL, orig_addr, len, pgoff, flags);
+
+	return addr;
+}
+EXPORT_SYMBOL(get_fb_unmapped_area);
+
+/* Essentially the same as PowerPC.  */
+static unsigned long mmap_rnd(void)
+{
+	unsigned long rnd = 0UL;
+
+	if (current->flags & PF_RANDOMIZE) {
+		unsigned long val = get_random_int();
+		if (test_thread_flag(TIF_32BIT))
+			rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
+		else
+			rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
+	}
+	return rnd << PAGE_SHIFT;
+}
+
+void arch_pick_mmap_layout(struct mm_struct *mm)
+{
+	unsigned long random_factor = mmap_rnd();
+	unsigned long gap;
+
+	/*
+	 * Fall back to the standard layout if the personality
+	 * bit is set, or if the expected stack growth is unlimited:
+	 */
+	gap = rlimit(RLIMIT_STACK);
+	if (!test_thread_flag(TIF_32BIT) ||
+	    (current->personality & ADDR_COMPAT_LAYOUT) ||
+	    gap == RLIM_INFINITY ||
+	    sysctl_legacy_va_layout) {
+		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
+		mm->get_unmapped_area = arch_get_unmapped_area;
+		mm->unmap_area = arch_unmap_area;
+	} else {
+		/* We know it's 32-bit */
+		unsigned long task_size = STACK_TOP32;
+
+		if (gap < 128 * 1024 * 1024)
+			gap = 128 * 1024 * 1024;
+		if (gap > (task_size / 6 * 5))
+			gap = (task_size / 6 * 5);
+
+		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
+		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
+		mm->unmap_area = arch_unmap_area_topdown;
+	}
+}
+
+/*
+ * sys_pipe() is the normal C calling standard for creating
+ * a pipe. It's not the way unix traditionally does this, though.
+ */
+SYSCALL_DEFINE1(sparc_pipe_real, struct pt_regs *, regs)
+{
+	int fd[2];
+	int error;
+
+	error = do_pipe_flags(fd, 0);
+	if (error)
+		goto out;
+	regs->u_regs[UREG_I1] = fd[1];
+	error = fd[0];
+out:
+	return error;
+}
+
+/*
+ * sys_ipc() is the de-multiplexer for the SysV IPC calls..
+ *
+ * This is really horribly ugly.
+ */
+
+SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
+		unsigned long, third, void __user *, ptr, long, fifth)
+{
+	long err;
+
+	/* No need for backward compatibility. We can start fresh... */
+	if (call <= SEMCTL) {
+		switch (call) {
+		case SEMOP:
+			err = sys_semtimedop(first, ptr,
+					     (unsigned)second, NULL);
+			goto out;
+		case SEMTIMEDOP:
+			err = sys_semtimedop(first, ptr, (unsigned)second,
+				(const struct timespec __user *)
+					     (unsigned long) fifth);
+			goto out;
+		case SEMGET:
+			err = sys_semget(first, (int)second, (int)third);
+			goto out;
+		case SEMCTL: {
+			err = sys_semctl(first, second,
+					 (int)third | IPC_64,
+					 (union semun) ptr);
+			goto out;
+		}
+		default:
+			err = -ENOSYS;
+			goto out;
+		}
+	}
+	if (call <= MSGCTL) {
+		switch (call) {
+		case MSGSND:
+			err = sys_msgsnd(first, ptr, (size_t)second,
+					 (int)third);
+			goto out;
+		case MSGRCV:
+			err = sys_msgrcv(first, ptr, (size_t)second, fifth,
+					 (int)third);
+			goto out;
+		case MSGGET:
+			err = sys_msgget((key_t)first, (int)second);
+			goto out;
+		case MSGCTL:
+			err = sys_msgctl(first, (int)second | IPC_64, ptr);
+			goto out;
+		default:
+			err = -ENOSYS;
+			goto out;
+		}
+	}
+	if (call <= SHMCTL) {
+		switch (call) {
+		case SHMAT: {
+			ulong raddr;
+			err = do_shmat(first, ptr, (int)second, &raddr);
+			if (!err) {
+				if (put_user(raddr,
+					     (ulong __user *) third))
+					err = -EFAULT;
+			}
+			goto out;
+		}
+		case SHMDT:
+			err = sys_shmdt(ptr);
+			goto out;
+		case SHMGET:
+			err = sys_shmget(first, (size_t)second, (int)third);
+			goto out;
+		case SHMCTL:
+			err = sys_shmctl(first, (int)second | IPC_64, ptr);
+			goto out;
+		default:
+			err = -ENOSYS;
+			goto out;
+		}
+	} else {
+		err = -ENOSYS;
+	}
+out:
+	return err;
+}
+
+SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
+{
+	int ret;
+
+	if (current->personality == PER_LINUX32 &&
+	    personality == PER_LINUX)
+		personality = PER_LINUX32;
+	ret = sys_personality(personality);
+	if (ret == PER_LINUX32)
+		ret = PER_LINUX;
+
+	return ret;
+}
+
+int sparc_mmap_check(unsigned long addr, unsigned long len)
+{
+	if (test_thread_flag(TIF_32BIT)) {
+		if (len >= STACK_TOP32)
+			return -EINVAL;
+
+		if (addr > STACK_TOP32 - len)
+			return -EINVAL;
+	} else {
+		if (len >= VA_EXCLUDE_START)
+			return -EINVAL;
+
+		if (invalid_64bit_range(addr, len))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* Linux version of mmap */
+SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
+		unsigned long, prot, unsigned long, flags, unsigned long, fd,
+		unsigned long, off)
+{
+	unsigned long retval = -EINVAL;
+
+	if ((off + PAGE_ALIGN(len)) < off)
+		goto out;
+	if (off & ~PAGE_MASK)
+		goto out;
+	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
+out:
+	return retval;
+}
+
+SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
+{
+	if (invalid_64bit_range(addr, len))
+		return -EINVAL;
+
+	return vm_munmap(addr, len);
+}
+
+extern unsigned long do_mremap(unsigned long addr,
+	unsigned long old_len, unsigned long new_len,
+	unsigned long flags, unsigned long new_addr);
+                
+SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
+		unsigned long, new_len, unsigned long, flags,
+		unsigned long, new_addr)
+{
+	unsigned long ret = -EINVAL;
+
+	if (test_thread_flag(TIF_32BIT))
+		goto out;
+
+	down_write(&current->mm->mmap_sem);
+	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
+	up_write(&current->mm->mmap_sem);
+out:
+	return ret;       
+}
+
+/* we come to here via sys_nis_syscall so it can setup the regs argument */
+asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
+{
+	static int count;
+	
+	/* Don't make the system unusable, if someone goes stuck */
+	if (count++ > 5)
+		return -ENOSYS;
+
+	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
+#ifdef DEBUG_UNIMP_SYSCALL	
+	show_regs (regs);
+#endif
+
+	return -ENOSYS;
+}
+
+/* #define DEBUG_SPARC_BREAKPOINT */
+
+asmlinkage void sparc_breakpoint(struct pt_regs *regs)
+{
+	siginfo_t info;
+
+	if (test_thread_flag(TIF_32BIT)) {
+		regs->tpc &= 0xffffffff;
+		regs->tnpc &= 0xffffffff;
+	}
+#ifdef DEBUG_SPARC_BREAKPOINT
+        printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
+#endif
+	info.si_signo = SIGTRAP;
+	info.si_errno = 0;
+	info.si_code = TRAP_BRKPT;
+	info.si_addr = (void __user *)regs->tpc;
+	info.si_trapno = 0;
+	force_sig_info(SIGTRAP, &info, current);
+#ifdef DEBUG_SPARC_BREAKPOINT
+	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
+#endif
+}
+
+extern void check_pending(int signum);
+
+SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
+{
+        int nlen, err;
+
+	if (len < 0)
+		return -EINVAL;
+
+ 	down_read(&uts_sem);
+ 	
+	nlen = strlen(utsname()->domainname) + 1;
+	err = -EINVAL;
+	if (nlen > len)
+		goto out;
+
+	err = -EFAULT;
+	if (!copy_to_user(name, utsname()->domainname, nlen))
+		err = 0;
+
+out:
+	up_read(&uts_sem);
+	return err;
+}
+
+SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
+		utrap_handler_t, new_p, utrap_handler_t, new_d,
+		utrap_handler_t __user *, old_p,
+		utrap_handler_t __user *, old_d)
+{
+	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
+		return -EINVAL;
+	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
+		if (old_p) {
+			if (!current_thread_info()->utraps) {
+				if (put_user(NULL, old_p))
+					return -EFAULT;
+			} else {
+				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
+					return -EFAULT;
+			}
+		}
+		if (old_d) {
+			if (put_user(NULL, old_d))
+				return -EFAULT;
+		}
+		return 0;
+	}
+	if (!current_thread_info()->utraps) {
+		current_thread_info()->utraps =
+			kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL);
+		if (!current_thread_info()->utraps)
+			return -ENOMEM;
+		current_thread_info()->utraps[0] = 1;
+	} else {
+		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
+		    current_thread_info()->utraps[0] > 1) {
+			unsigned long *p = current_thread_info()->utraps;
+
+			current_thread_info()->utraps =
+				kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long),
+					GFP_KERNEL);
+			if (!current_thread_info()->utraps) {
+				current_thread_info()->utraps = p;
+				return -ENOMEM;
+			}
+			p[0]--;
+			current_thread_info()->utraps[0] = 1;
+			memcpy(current_thread_info()->utraps+1, p+1,
+			       UT_TRAP_INSTRUCTION_31*sizeof(long));
+		}
+	}
+	if (old_p) {
+		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
+			return -EFAULT;
+	}
+	if (old_d) {
+		if (put_user(NULL, old_d))
+			return -EFAULT;
+	}
+	current_thread_info()->utraps[type] = (long)new_p;
+
+	return 0;
+}
+
+asmlinkage long sparc_memory_ordering(unsigned long model,
+				      struct pt_regs *regs)
+{
+	if (model >= 3)
+		return -EINVAL;
+	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
+	return 0;
+}
+
+SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
+		struct sigaction __user *, oact, void __user *, restorer,
+		size_t, sigsetsize)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (act) {
+		new_ka.ka_restorer = restorer;
+		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
+			return -EFAULT;
+	}
+
+	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+	if (!ret && oact) {
+		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
+			return -EFAULT;
+	}
+
+	return ret;
+}
+
+/*
+ * 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[])
+{
+	long __res;
+	register long __g1 __asm__ ("g1") = __NR_execve;
+	register long __o0 __asm__ ("o0") = (long)(filename);
+	register long __o1 __asm__ ("o1") = (long)(argv);
+	register long __o2 __asm__ ("o2") = (long)(envp);
+	asm volatile ("t 0x6d\n\t"
+		      "sub %%g0, %%o0, %0\n\t"
+		      "movcc %%xcc, %%o0, %0\n\t"
+		      : "=r" (__res), "=&r" (__o0)
+		      : "1" (__o0), "r" (__o1), "r" (__o2), "r" (__g1)
+		      : "cc");
+	return __res;
+}