xref: /openbmc/linux/arch/sparc/kernel/sys_sparc_64.c (revision 95e9fd10)
1 /* linux/arch/sparc64/kernel/sys_sparc.c
2  *
3  * This file contains various random system calls that
4  * have a non-standard calling sequence on the Linux/sparc
5  * platform.
6  */
7 
8 #include <linux/errno.h>
9 #include <linux/types.h>
10 #include <linux/sched.h>
11 #include <linux/fs.h>
12 #include <linux/file.h>
13 #include <linux/mm.h>
14 #include <linux/sem.h>
15 #include <linux/msg.h>
16 #include <linux/shm.h>
17 #include <linux/stat.h>
18 #include <linux/mman.h>
19 #include <linux/utsname.h>
20 #include <linux/smp.h>
21 #include <linux/slab.h>
22 #include <linux/syscalls.h>
23 #include <linux/ipc.h>
24 #include <linux/personality.h>
25 #include <linux/random.h>
26 #include <linux/export.h>
27 
28 #include <asm/uaccess.h>
29 #include <asm/utrap.h>
30 #include <asm/unistd.h>
31 
32 #include "entry.h"
33 #include "systbls.h"
34 
35 /* #define DEBUG_UNIMP_SYSCALL */
36 
37 asmlinkage unsigned long sys_getpagesize(void)
38 {
39 	return PAGE_SIZE;
40 }
41 
42 #define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL))
43 #define VA_EXCLUDE_END   (0xfffff80000000000UL + (1UL << 32UL))
44 
45 /* Does addr --> addr+len fall within 4GB of the VA-space hole or
46  * overflow past the end of the 64-bit address space?
47  */
48 static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
49 {
50 	unsigned long va_exclude_start, va_exclude_end;
51 
52 	va_exclude_start = VA_EXCLUDE_START;
53 	va_exclude_end   = VA_EXCLUDE_END;
54 
55 	if (unlikely(len >= va_exclude_start))
56 		return 1;
57 
58 	if (unlikely((addr + len) < addr))
59 		return 1;
60 
61 	if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
62 		     ((addr + len) >= va_exclude_start &&
63 		      (addr + len) < va_exclude_end)))
64 		return 1;
65 
66 	return 0;
67 }
68 
69 /* These functions differ from the default implementations in
70  * mm/mmap.c in two ways:
71  *
72  * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
73  *    for fixed such mappings we just validate what the user gave us.
74  * 2) For 64-bit tasks we avoid mapping anything within 4GB of
75  *    the spitfire/niagara VA-hole.
76  */
77 
78 static inline unsigned long COLOUR_ALIGN(unsigned long addr,
79 					 unsigned long pgoff)
80 {
81 	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
82 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
83 
84 	return base + off;
85 }
86 
87 static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr,
88 					      unsigned long pgoff)
89 {
90 	unsigned long base = addr & ~(SHMLBA-1);
91 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
92 
93 	if (base + off <= addr)
94 		return base + off;
95 	return base - off;
96 }
97 
98 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
99 {
100 	struct mm_struct *mm = current->mm;
101 	struct vm_area_struct * vma;
102 	unsigned long task_size = TASK_SIZE;
103 	unsigned long start_addr;
104 	int do_color_align;
105 
106 	if (flags & MAP_FIXED) {
107 		/* We do not accept a shared mapping if it would violate
108 		 * cache aliasing constraints.
109 		 */
110 		if ((flags & MAP_SHARED) &&
111 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
112 			return -EINVAL;
113 		return addr;
114 	}
115 
116 	if (test_thread_flag(TIF_32BIT))
117 		task_size = STACK_TOP32;
118 	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
119 		return -ENOMEM;
120 
121 	do_color_align = 0;
122 	if (filp || (flags & MAP_SHARED))
123 		do_color_align = 1;
124 
125 	if (addr) {
126 		if (do_color_align)
127 			addr = COLOUR_ALIGN(addr, pgoff);
128 		else
129 			addr = PAGE_ALIGN(addr);
130 
131 		vma = find_vma(mm, addr);
132 		if (task_size - len >= addr &&
133 		    (!vma || addr + len <= vma->vm_start))
134 			return addr;
135 	}
136 
137 	if (len > mm->cached_hole_size) {
138 	        start_addr = addr = mm->free_area_cache;
139 	} else {
140 	        start_addr = addr = TASK_UNMAPPED_BASE;
141 	        mm->cached_hole_size = 0;
142 	}
143 
144 	task_size -= len;
145 
146 full_search:
147 	if (do_color_align)
148 		addr = COLOUR_ALIGN(addr, pgoff);
149 	else
150 		addr = PAGE_ALIGN(addr);
151 
152 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
153 		/* At this point:  (!vma || addr < vma->vm_end). */
154 		if (addr < VA_EXCLUDE_START &&
155 		    (addr + len) >= VA_EXCLUDE_START) {
156 			addr = VA_EXCLUDE_END;
157 			vma = find_vma(mm, VA_EXCLUDE_END);
158 		}
159 		if (unlikely(task_size < addr)) {
160 			if (start_addr != TASK_UNMAPPED_BASE) {
161 				start_addr = addr = TASK_UNMAPPED_BASE;
162 				mm->cached_hole_size = 0;
163 				goto full_search;
164 			}
165 			return -ENOMEM;
166 		}
167 		if (likely(!vma || addr + len <= vma->vm_start)) {
168 			/*
169 			 * Remember the place where we stopped the search:
170 			 */
171 			mm->free_area_cache = addr + len;
172 			return addr;
173 		}
174 		if (addr + mm->cached_hole_size < vma->vm_start)
175 		        mm->cached_hole_size = vma->vm_start - addr;
176 
177 		addr = vma->vm_end;
178 		if (do_color_align)
179 			addr = COLOUR_ALIGN(addr, pgoff);
180 	}
181 }
182 
183 unsigned long
184 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
185 			  const unsigned long len, const unsigned long pgoff,
186 			  const unsigned long flags)
187 {
188 	struct vm_area_struct *vma;
189 	struct mm_struct *mm = current->mm;
190 	unsigned long task_size = STACK_TOP32;
191 	unsigned long addr = addr0;
192 	int do_color_align;
193 
194 	/* This should only ever run for 32-bit processes.  */
195 	BUG_ON(!test_thread_flag(TIF_32BIT));
196 
197 	if (flags & MAP_FIXED) {
198 		/* We do not accept a shared mapping if it would violate
199 		 * cache aliasing constraints.
200 		 */
201 		if ((flags & MAP_SHARED) &&
202 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
203 			return -EINVAL;
204 		return addr;
205 	}
206 
207 	if (unlikely(len > task_size))
208 		return -ENOMEM;
209 
210 	do_color_align = 0;
211 	if (filp || (flags & MAP_SHARED))
212 		do_color_align = 1;
213 
214 	/* requesting a specific address */
215 	if (addr) {
216 		if (do_color_align)
217 			addr = COLOUR_ALIGN(addr, pgoff);
218 		else
219 			addr = PAGE_ALIGN(addr);
220 
221 		vma = find_vma(mm, addr);
222 		if (task_size - len >= addr &&
223 		    (!vma || addr + len <= vma->vm_start))
224 			return addr;
225 	}
226 
227 	/* check if free_area_cache is useful for us */
228 	if (len <= mm->cached_hole_size) {
229  	        mm->cached_hole_size = 0;
230  		mm->free_area_cache = mm->mmap_base;
231  	}
232 
233 	/* either no address requested or can't fit in requested address hole */
234 	addr = mm->free_area_cache;
235 	if (do_color_align) {
236 		unsigned long base = COLOUR_ALIGN_DOWN(addr-len, pgoff);
237 
238 		addr = base + len;
239 	}
240 
241 	/* make sure it can fit in the remaining address space */
242 	if (likely(addr > len)) {
243 		vma = find_vma(mm, addr-len);
244 		if (!vma || addr <= vma->vm_start) {
245 			/* remember the address as a hint for next time */
246 			return (mm->free_area_cache = addr-len);
247 		}
248 	}
249 
250 	if (unlikely(mm->mmap_base < len))
251 		goto bottomup;
252 
253 	addr = mm->mmap_base-len;
254 	if (do_color_align)
255 		addr = COLOUR_ALIGN_DOWN(addr, pgoff);
256 
257 	do {
258 		/*
259 		 * Lookup failure means no vma is above this address,
260 		 * else if new region fits below vma->vm_start,
261 		 * return with success:
262 		 */
263 		vma = find_vma(mm, addr);
264 		if (likely(!vma || addr+len <= vma->vm_start)) {
265 			/* remember the address as a hint for next time */
266 			return (mm->free_area_cache = addr);
267 		}
268 
269  		/* remember the largest hole we saw so far */
270  		if (addr + mm->cached_hole_size < vma->vm_start)
271  		        mm->cached_hole_size = vma->vm_start - addr;
272 
273 		/* try just below the current vma->vm_start */
274 		addr = vma->vm_start-len;
275 		if (do_color_align)
276 			addr = COLOUR_ALIGN_DOWN(addr, pgoff);
277 	} while (likely(len < vma->vm_start));
278 
279 bottomup:
280 	/*
281 	 * A failed mmap() very likely causes application failure,
282 	 * so fall back to the bottom-up function here. This scenario
283 	 * can happen with large stack limits and large mmap()
284 	 * allocations.
285 	 */
286 	mm->cached_hole_size = ~0UL;
287   	mm->free_area_cache = TASK_UNMAPPED_BASE;
288 	addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
289 	/*
290 	 * Restore the topdown base:
291 	 */
292 	mm->free_area_cache = mm->mmap_base;
293 	mm->cached_hole_size = ~0UL;
294 
295 	return addr;
296 }
297 
298 /* Try to align mapping such that we align it as much as possible. */
299 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
300 {
301 	unsigned long align_goal, addr = -ENOMEM;
302 	unsigned long (*get_area)(struct file *, unsigned long,
303 				  unsigned long, unsigned long, unsigned long);
304 
305 	get_area = current->mm->get_unmapped_area;
306 
307 	if (flags & MAP_FIXED) {
308 		/* Ok, don't mess with it. */
309 		return get_area(NULL, orig_addr, len, pgoff, flags);
310 	}
311 	flags &= ~MAP_SHARED;
312 
313 	align_goal = PAGE_SIZE;
314 	if (len >= (4UL * 1024 * 1024))
315 		align_goal = (4UL * 1024 * 1024);
316 	else if (len >= (512UL * 1024))
317 		align_goal = (512UL * 1024);
318 	else if (len >= (64UL * 1024))
319 		align_goal = (64UL * 1024);
320 
321 	do {
322 		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
323 		if (!(addr & ~PAGE_MASK)) {
324 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
325 			break;
326 		}
327 
328 		if (align_goal == (4UL * 1024 * 1024))
329 			align_goal = (512UL * 1024);
330 		else if (align_goal == (512UL * 1024))
331 			align_goal = (64UL * 1024);
332 		else
333 			align_goal = PAGE_SIZE;
334 	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
335 
336 	/* Mapping is smaller than 64K or larger areas could not
337 	 * be obtained.
338 	 */
339 	if (addr & ~PAGE_MASK)
340 		addr = get_area(NULL, orig_addr, len, pgoff, flags);
341 
342 	return addr;
343 }
344 EXPORT_SYMBOL(get_fb_unmapped_area);
345 
346 /* Essentially the same as PowerPC.  */
347 static unsigned long mmap_rnd(void)
348 {
349 	unsigned long rnd = 0UL;
350 
351 	if (current->flags & PF_RANDOMIZE) {
352 		unsigned long val = get_random_int();
353 		if (test_thread_flag(TIF_32BIT))
354 			rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
355 		else
356 			rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
357 	}
358 	return rnd << PAGE_SHIFT;
359 }
360 
361 void arch_pick_mmap_layout(struct mm_struct *mm)
362 {
363 	unsigned long random_factor = mmap_rnd();
364 	unsigned long gap;
365 
366 	/*
367 	 * Fall back to the standard layout if the personality
368 	 * bit is set, or if the expected stack growth is unlimited:
369 	 */
370 	gap = rlimit(RLIMIT_STACK);
371 	if (!test_thread_flag(TIF_32BIT) ||
372 	    (current->personality & ADDR_COMPAT_LAYOUT) ||
373 	    gap == RLIM_INFINITY ||
374 	    sysctl_legacy_va_layout) {
375 		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
376 		mm->get_unmapped_area = arch_get_unmapped_area;
377 		mm->unmap_area = arch_unmap_area;
378 	} else {
379 		/* We know it's 32-bit */
380 		unsigned long task_size = STACK_TOP32;
381 
382 		if (gap < 128 * 1024 * 1024)
383 			gap = 128 * 1024 * 1024;
384 		if (gap > (task_size / 6 * 5))
385 			gap = (task_size / 6 * 5);
386 
387 		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
388 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
389 		mm->unmap_area = arch_unmap_area_topdown;
390 	}
391 }
392 
393 /*
394  * sys_pipe() is the normal C calling standard for creating
395  * a pipe. It's not the way unix traditionally does this, though.
396  */
397 SYSCALL_DEFINE1(sparc_pipe_real, struct pt_regs *, regs)
398 {
399 	int fd[2];
400 	int error;
401 
402 	error = do_pipe_flags(fd, 0);
403 	if (error)
404 		goto out;
405 	regs->u_regs[UREG_I1] = fd[1];
406 	error = fd[0];
407 out:
408 	return error;
409 }
410 
411 /*
412  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
413  *
414  * This is really horribly ugly.
415  */
416 
417 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
418 		unsigned long, third, void __user *, ptr, long, fifth)
419 {
420 	long err;
421 
422 	/* No need for backward compatibility. We can start fresh... */
423 	if (call <= SEMCTL) {
424 		switch (call) {
425 		case SEMOP:
426 			err = sys_semtimedop(first, ptr,
427 					     (unsigned)second, NULL);
428 			goto out;
429 		case SEMTIMEDOP:
430 			err = sys_semtimedop(first, ptr, (unsigned)second,
431 				(const struct timespec __user *)
432 					     (unsigned long) fifth);
433 			goto out;
434 		case SEMGET:
435 			err = sys_semget(first, (int)second, (int)third);
436 			goto out;
437 		case SEMCTL: {
438 			err = sys_semctl(first, second,
439 					 (int)third | IPC_64,
440 					 (union semun) ptr);
441 			goto out;
442 		}
443 		default:
444 			err = -ENOSYS;
445 			goto out;
446 		}
447 	}
448 	if (call <= MSGCTL) {
449 		switch (call) {
450 		case MSGSND:
451 			err = sys_msgsnd(first, ptr, (size_t)second,
452 					 (int)third);
453 			goto out;
454 		case MSGRCV:
455 			err = sys_msgrcv(first, ptr, (size_t)second, fifth,
456 					 (int)third);
457 			goto out;
458 		case MSGGET:
459 			err = sys_msgget((key_t)first, (int)second);
460 			goto out;
461 		case MSGCTL:
462 			err = sys_msgctl(first, (int)second | IPC_64, ptr);
463 			goto out;
464 		default:
465 			err = -ENOSYS;
466 			goto out;
467 		}
468 	}
469 	if (call <= SHMCTL) {
470 		switch (call) {
471 		case SHMAT: {
472 			ulong raddr;
473 			err = do_shmat(first, ptr, (int)second, &raddr, SHMLBA);
474 			if (!err) {
475 				if (put_user(raddr,
476 					     (ulong __user *) third))
477 					err = -EFAULT;
478 			}
479 			goto out;
480 		}
481 		case SHMDT:
482 			err = sys_shmdt(ptr);
483 			goto out;
484 		case SHMGET:
485 			err = sys_shmget(first, (size_t)second, (int)third);
486 			goto out;
487 		case SHMCTL:
488 			err = sys_shmctl(first, (int)second | IPC_64, ptr);
489 			goto out;
490 		default:
491 			err = -ENOSYS;
492 			goto out;
493 		}
494 	} else {
495 		err = -ENOSYS;
496 	}
497 out:
498 	return err;
499 }
500 
501 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
502 {
503 	int ret;
504 
505 	if (personality(current->personality) == PER_LINUX32 &&
506 	    personality(personality) == PER_LINUX)
507 		personality |= PER_LINUX32;
508 	ret = sys_personality(personality);
509 	if (personality(ret) == PER_LINUX32)
510 		ret &= ~PER_LINUX32;
511 
512 	return ret;
513 }
514 
515 int sparc_mmap_check(unsigned long addr, unsigned long len)
516 {
517 	if (test_thread_flag(TIF_32BIT)) {
518 		if (len >= STACK_TOP32)
519 			return -EINVAL;
520 
521 		if (addr > STACK_TOP32 - len)
522 			return -EINVAL;
523 	} else {
524 		if (len >= VA_EXCLUDE_START)
525 			return -EINVAL;
526 
527 		if (invalid_64bit_range(addr, len))
528 			return -EINVAL;
529 	}
530 
531 	return 0;
532 }
533 
534 /* Linux version of mmap */
535 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
536 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
537 		unsigned long, off)
538 {
539 	unsigned long retval = -EINVAL;
540 
541 	if ((off + PAGE_ALIGN(len)) < off)
542 		goto out;
543 	if (off & ~PAGE_MASK)
544 		goto out;
545 	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
546 out:
547 	return retval;
548 }
549 
550 SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
551 {
552 	if (invalid_64bit_range(addr, len))
553 		return -EINVAL;
554 
555 	return vm_munmap(addr, len);
556 }
557 
558 extern unsigned long do_mremap(unsigned long addr,
559 	unsigned long old_len, unsigned long new_len,
560 	unsigned long flags, unsigned long new_addr);
561 
562 SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
563 		unsigned long, new_len, unsigned long, flags,
564 		unsigned long, new_addr)
565 {
566 	if (test_thread_flag(TIF_32BIT))
567 		return -EINVAL;
568 	return sys_mremap(addr, old_len, new_len, flags, new_addr);
569 }
570 
571 /* we come to here via sys_nis_syscall so it can setup the regs argument */
572 asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
573 {
574 	static int count;
575 
576 	/* Don't make the system unusable, if someone goes stuck */
577 	if (count++ > 5)
578 		return -ENOSYS;
579 
580 	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
581 #ifdef DEBUG_UNIMP_SYSCALL
582 	show_regs (regs);
583 #endif
584 
585 	return -ENOSYS;
586 }
587 
588 /* #define DEBUG_SPARC_BREAKPOINT */
589 
590 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
591 {
592 	siginfo_t info;
593 
594 	if (test_thread_flag(TIF_32BIT)) {
595 		regs->tpc &= 0xffffffff;
596 		regs->tnpc &= 0xffffffff;
597 	}
598 #ifdef DEBUG_SPARC_BREAKPOINT
599         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
600 #endif
601 	info.si_signo = SIGTRAP;
602 	info.si_errno = 0;
603 	info.si_code = TRAP_BRKPT;
604 	info.si_addr = (void __user *)regs->tpc;
605 	info.si_trapno = 0;
606 	force_sig_info(SIGTRAP, &info, current);
607 #ifdef DEBUG_SPARC_BREAKPOINT
608 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
609 #endif
610 }
611 
612 extern void check_pending(int signum);
613 
614 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
615 {
616         int nlen, err;
617 
618 	if (len < 0)
619 		return -EINVAL;
620 
621  	down_read(&uts_sem);
622 
623 	nlen = strlen(utsname()->domainname) + 1;
624 	err = -EINVAL;
625 	if (nlen > len)
626 		goto out;
627 
628 	err = -EFAULT;
629 	if (!copy_to_user(name, utsname()->domainname, nlen))
630 		err = 0;
631 
632 out:
633 	up_read(&uts_sem);
634 	return err;
635 }
636 
637 SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
638 		utrap_handler_t, new_p, utrap_handler_t, new_d,
639 		utrap_handler_t __user *, old_p,
640 		utrap_handler_t __user *, old_d)
641 {
642 	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
643 		return -EINVAL;
644 	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
645 		if (old_p) {
646 			if (!current_thread_info()->utraps) {
647 				if (put_user(NULL, old_p))
648 					return -EFAULT;
649 			} else {
650 				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
651 					return -EFAULT;
652 			}
653 		}
654 		if (old_d) {
655 			if (put_user(NULL, old_d))
656 				return -EFAULT;
657 		}
658 		return 0;
659 	}
660 	if (!current_thread_info()->utraps) {
661 		current_thread_info()->utraps =
662 			kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL);
663 		if (!current_thread_info()->utraps)
664 			return -ENOMEM;
665 		current_thread_info()->utraps[0] = 1;
666 	} else {
667 		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
668 		    current_thread_info()->utraps[0] > 1) {
669 			unsigned long *p = current_thread_info()->utraps;
670 
671 			current_thread_info()->utraps =
672 				kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long),
673 					GFP_KERNEL);
674 			if (!current_thread_info()->utraps) {
675 				current_thread_info()->utraps = p;
676 				return -ENOMEM;
677 			}
678 			p[0]--;
679 			current_thread_info()->utraps[0] = 1;
680 			memcpy(current_thread_info()->utraps+1, p+1,
681 			       UT_TRAP_INSTRUCTION_31*sizeof(long));
682 		}
683 	}
684 	if (old_p) {
685 		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
686 			return -EFAULT;
687 	}
688 	if (old_d) {
689 		if (put_user(NULL, old_d))
690 			return -EFAULT;
691 	}
692 	current_thread_info()->utraps[type] = (long)new_p;
693 
694 	return 0;
695 }
696 
697 asmlinkage long sparc_memory_ordering(unsigned long model,
698 				      struct pt_regs *regs)
699 {
700 	if (model >= 3)
701 		return -EINVAL;
702 	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
703 	return 0;
704 }
705 
706 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
707 		struct sigaction __user *, oact, void __user *, restorer,
708 		size_t, sigsetsize)
709 {
710 	struct k_sigaction new_ka, old_ka;
711 	int ret;
712 
713 	/* XXX: Don't preclude handling different sized sigset_t's.  */
714 	if (sigsetsize != sizeof(sigset_t))
715 		return -EINVAL;
716 
717 	if (act) {
718 		new_ka.ka_restorer = restorer;
719 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
720 			return -EFAULT;
721 	}
722 
723 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
724 
725 	if (!ret && oact) {
726 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
727 			return -EFAULT;
728 	}
729 
730 	return ret;
731 }
732 
733 /*
734  * Do a system call from kernel instead of calling sys_execve so we
735  * end up with proper pt_regs.
736  */
737 int kernel_execve(const char *filename,
738 		  const char *const argv[],
739 		  const char *const envp[])
740 {
741 	long __res;
742 	register long __g1 __asm__ ("g1") = __NR_execve;
743 	register long __o0 __asm__ ("o0") = (long)(filename);
744 	register long __o1 __asm__ ("o1") = (long)(argv);
745 	register long __o2 __asm__ ("o2") = (long)(envp);
746 	asm volatile ("t 0x6d\n\t"
747 		      "sub %%g0, %%o0, %0\n\t"
748 		      "movcc %%xcc, %%o0, %0\n\t"
749 		      : "=r" (__res), "=&r" (__o0)
750 		      : "1" (__o0), "r" (__o1), "r" (__o2), "r" (__g1)
751 		      : "cc");
752 	return __res;
753 }
754