xref: /openbmc/linux/arch/sparc/kernel/sys_sparc_64.c (revision 4800cd83)
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/module.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 /* Does start,end straddle the VA-space hole?  */
70 static inline int straddles_64bit_va_hole(unsigned long start, unsigned long end)
71 {
72 	unsigned long va_exclude_start, va_exclude_end;
73 
74 	va_exclude_start = VA_EXCLUDE_START;
75 	va_exclude_end   = VA_EXCLUDE_END;
76 
77 	if (likely(start < va_exclude_start && end < va_exclude_start))
78 		return 0;
79 
80 	if (likely(start >= va_exclude_end && end >= va_exclude_end))
81 		return 0;
82 
83 	return 1;
84 }
85 
86 /* These functions differ from the default implementations in
87  * mm/mmap.c in two ways:
88  *
89  * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
90  *    for fixed such mappings we just validate what the user gave us.
91  * 2) For 64-bit tasks we avoid mapping anything within 4GB of
92  *    the spitfire/niagara VA-hole.
93  */
94 
95 static inline unsigned long COLOUR_ALIGN(unsigned long addr,
96 					 unsigned long pgoff)
97 {
98 	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
99 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
100 
101 	return base + off;
102 }
103 
104 static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr,
105 					      unsigned long pgoff)
106 {
107 	unsigned long base = addr & ~(SHMLBA-1);
108 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
109 
110 	if (base + off <= addr)
111 		return base + off;
112 	return base - off;
113 }
114 
115 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
116 {
117 	struct mm_struct *mm = current->mm;
118 	struct vm_area_struct * vma;
119 	unsigned long task_size = TASK_SIZE;
120 	unsigned long start_addr;
121 	int do_color_align;
122 
123 	if (flags & MAP_FIXED) {
124 		/* We do not accept a shared mapping if it would violate
125 		 * cache aliasing constraints.
126 		 */
127 		if ((flags & MAP_SHARED) &&
128 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
129 			return -EINVAL;
130 		return addr;
131 	}
132 
133 	if (test_thread_flag(TIF_32BIT))
134 		task_size = STACK_TOP32;
135 	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
136 		return -ENOMEM;
137 
138 	do_color_align = 0;
139 	if (filp || (flags & MAP_SHARED))
140 		do_color_align = 1;
141 
142 	if (addr) {
143 		if (do_color_align)
144 			addr = COLOUR_ALIGN(addr, pgoff);
145 		else
146 			addr = PAGE_ALIGN(addr);
147 
148 		vma = find_vma(mm, addr);
149 		if (task_size - len >= addr &&
150 		    (!vma || addr + len <= vma->vm_start))
151 			return addr;
152 	}
153 
154 	if (len > mm->cached_hole_size) {
155 	        start_addr = addr = mm->free_area_cache;
156 	} else {
157 	        start_addr = addr = TASK_UNMAPPED_BASE;
158 	        mm->cached_hole_size = 0;
159 	}
160 
161 	task_size -= len;
162 
163 full_search:
164 	if (do_color_align)
165 		addr = COLOUR_ALIGN(addr, pgoff);
166 	else
167 		addr = PAGE_ALIGN(addr);
168 
169 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
170 		/* At this point:  (!vma || addr < vma->vm_end). */
171 		if (addr < VA_EXCLUDE_START &&
172 		    (addr + len) >= VA_EXCLUDE_START) {
173 			addr = VA_EXCLUDE_END;
174 			vma = find_vma(mm, VA_EXCLUDE_END);
175 		}
176 		if (unlikely(task_size < addr)) {
177 			if (start_addr != TASK_UNMAPPED_BASE) {
178 				start_addr = addr = TASK_UNMAPPED_BASE;
179 				mm->cached_hole_size = 0;
180 				goto full_search;
181 			}
182 			return -ENOMEM;
183 		}
184 		if (likely(!vma || addr + len <= vma->vm_start)) {
185 			/*
186 			 * Remember the place where we stopped the search:
187 			 */
188 			mm->free_area_cache = addr + len;
189 			return addr;
190 		}
191 		if (addr + mm->cached_hole_size < vma->vm_start)
192 		        mm->cached_hole_size = vma->vm_start - addr;
193 
194 		addr = vma->vm_end;
195 		if (do_color_align)
196 			addr = COLOUR_ALIGN(addr, pgoff);
197 	}
198 }
199 
200 unsigned long
201 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
202 			  const unsigned long len, const unsigned long pgoff,
203 			  const unsigned long flags)
204 {
205 	struct vm_area_struct *vma;
206 	struct mm_struct *mm = current->mm;
207 	unsigned long task_size = STACK_TOP32;
208 	unsigned long addr = addr0;
209 	int do_color_align;
210 
211 	/* This should only ever run for 32-bit processes.  */
212 	BUG_ON(!test_thread_flag(TIF_32BIT));
213 
214 	if (flags & MAP_FIXED) {
215 		/* We do not accept a shared mapping if it would violate
216 		 * cache aliasing constraints.
217 		 */
218 		if ((flags & MAP_SHARED) &&
219 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
220 			return -EINVAL;
221 		return addr;
222 	}
223 
224 	if (unlikely(len > task_size))
225 		return -ENOMEM;
226 
227 	do_color_align = 0;
228 	if (filp || (flags & MAP_SHARED))
229 		do_color_align = 1;
230 
231 	/* requesting a specific address */
232 	if (addr) {
233 		if (do_color_align)
234 			addr = COLOUR_ALIGN(addr, pgoff);
235 		else
236 			addr = PAGE_ALIGN(addr);
237 
238 		vma = find_vma(mm, addr);
239 		if (task_size - len >= addr &&
240 		    (!vma || addr + len <= vma->vm_start))
241 			return addr;
242 	}
243 
244 	/* check if free_area_cache is useful for us */
245 	if (len <= mm->cached_hole_size) {
246  	        mm->cached_hole_size = 0;
247  		mm->free_area_cache = mm->mmap_base;
248  	}
249 
250 	/* either no address requested or can't fit in requested address hole */
251 	addr = mm->free_area_cache;
252 	if (do_color_align) {
253 		unsigned long base = COLOUR_ALIGN_DOWN(addr-len, pgoff);
254 
255 		addr = base + len;
256 	}
257 
258 	/* make sure it can fit in the remaining address space */
259 	if (likely(addr > len)) {
260 		vma = find_vma(mm, addr-len);
261 		if (!vma || addr <= vma->vm_start) {
262 			/* remember the address as a hint for next time */
263 			return (mm->free_area_cache = addr-len);
264 		}
265 	}
266 
267 	if (unlikely(mm->mmap_base < len))
268 		goto bottomup;
269 
270 	addr = mm->mmap_base-len;
271 	if (do_color_align)
272 		addr = COLOUR_ALIGN_DOWN(addr, pgoff);
273 
274 	do {
275 		/*
276 		 * Lookup failure means no vma is above this address,
277 		 * else if new region fits below vma->vm_start,
278 		 * return with success:
279 		 */
280 		vma = find_vma(mm, addr);
281 		if (likely(!vma || addr+len <= vma->vm_start)) {
282 			/* remember the address as a hint for next time */
283 			return (mm->free_area_cache = addr);
284 		}
285 
286  		/* remember the largest hole we saw so far */
287  		if (addr + mm->cached_hole_size < vma->vm_start)
288  		        mm->cached_hole_size = vma->vm_start - addr;
289 
290 		/* try just below the current vma->vm_start */
291 		addr = vma->vm_start-len;
292 		if (do_color_align)
293 			addr = COLOUR_ALIGN_DOWN(addr, pgoff);
294 	} while (likely(len < vma->vm_start));
295 
296 bottomup:
297 	/*
298 	 * A failed mmap() very likely causes application failure,
299 	 * so fall back to the bottom-up function here. This scenario
300 	 * can happen with large stack limits and large mmap()
301 	 * allocations.
302 	 */
303 	mm->cached_hole_size = ~0UL;
304   	mm->free_area_cache = TASK_UNMAPPED_BASE;
305 	addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
306 	/*
307 	 * Restore the topdown base:
308 	 */
309 	mm->free_area_cache = mm->mmap_base;
310 	mm->cached_hole_size = ~0UL;
311 
312 	return addr;
313 }
314 
315 /* Try to align mapping such that we align it as much as possible. */
316 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
317 {
318 	unsigned long align_goal, addr = -ENOMEM;
319 	unsigned long (*get_area)(struct file *, unsigned long,
320 				  unsigned long, unsigned long, unsigned long);
321 
322 	get_area = current->mm->get_unmapped_area;
323 
324 	if (flags & MAP_FIXED) {
325 		/* Ok, don't mess with it. */
326 		return get_area(NULL, orig_addr, len, pgoff, flags);
327 	}
328 	flags &= ~MAP_SHARED;
329 
330 	align_goal = PAGE_SIZE;
331 	if (len >= (4UL * 1024 * 1024))
332 		align_goal = (4UL * 1024 * 1024);
333 	else if (len >= (512UL * 1024))
334 		align_goal = (512UL * 1024);
335 	else if (len >= (64UL * 1024))
336 		align_goal = (64UL * 1024);
337 
338 	do {
339 		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
340 		if (!(addr & ~PAGE_MASK)) {
341 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
342 			break;
343 		}
344 
345 		if (align_goal == (4UL * 1024 * 1024))
346 			align_goal = (512UL * 1024);
347 		else if (align_goal == (512UL * 1024))
348 			align_goal = (64UL * 1024);
349 		else
350 			align_goal = PAGE_SIZE;
351 	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
352 
353 	/* Mapping is smaller than 64K or larger areas could not
354 	 * be obtained.
355 	 */
356 	if (addr & ~PAGE_MASK)
357 		addr = get_area(NULL, orig_addr, len, pgoff, flags);
358 
359 	return addr;
360 }
361 EXPORT_SYMBOL(get_fb_unmapped_area);
362 
363 /* Essentially the same as PowerPC... */
364 void arch_pick_mmap_layout(struct mm_struct *mm)
365 {
366 	unsigned long random_factor = 0UL;
367 	unsigned long gap;
368 
369 	if (current->flags & PF_RANDOMIZE) {
370 		random_factor = get_random_int();
371 		if (test_thread_flag(TIF_32BIT))
372 			random_factor &= ((1 * 1024 * 1024) - 1);
373 		else
374 			random_factor = ((random_factor << PAGE_SHIFT) &
375 					 0xffffffffUL);
376 	}
377 
378 	/*
379 	 * Fall back to the standard layout if the personality
380 	 * bit is set, or if the expected stack growth is unlimited:
381 	 */
382 	gap = rlimit(RLIMIT_STACK);
383 	if (!test_thread_flag(TIF_32BIT) ||
384 	    (current->personality & ADDR_COMPAT_LAYOUT) ||
385 	    gap == RLIM_INFINITY ||
386 	    sysctl_legacy_va_layout) {
387 		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
388 		mm->get_unmapped_area = arch_get_unmapped_area;
389 		mm->unmap_area = arch_unmap_area;
390 	} else {
391 		/* We know it's 32-bit */
392 		unsigned long task_size = STACK_TOP32;
393 
394 		if (gap < 128 * 1024 * 1024)
395 			gap = 128 * 1024 * 1024;
396 		if (gap > (task_size / 6 * 5))
397 			gap = (task_size / 6 * 5);
398 
399 		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
400 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
401 		mm->unmap_area = arch_unmap_area_topdown;
402 	}
403 }
404 
405 /*
406  * sys_pipe() is the normal C calling standard for creating
407  * a pipe. It's not the way unix traditionally does this, though.
408  */
409 SYSCALL_DEFINE1(sparc_pipe_real, struct pt_regs *, regs)
410 {
411 	int fd[2];
412 	int error;
413 
414 	error = do_pipe_flags(fd, 0);
415 	if (error)
416 		goto out;
417 	regs->u_regs[UREG_I1] = fd[1];
418 	error = fd[0];
419 out:
420 	return error;
421 }
422 
423 /*
424  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
425  *
426  * This is really horribly ugly.
427  */
428 
429 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
430 		unsigned long, third, void __user *, ptr, long, fifth)
431 {
432 	long err;
433 
434 	/* No need for backward compatibility. We can start fresh... */
435 	if (call <= SEMCTL) {
436 		switch (call) {
437 		case SEMOP:
438 			err = sys_semtimedop(first, ptr,
439 					     (unsigned)second, NULL);
440 			goto out;
441 		case SEMTIMEDOP:
442 			err = sys_semtimedop(first, ptr, (unsigned)second,
443 				(const struct timespec __user *)
444 					     (unsigned long) fifth);
445 			goto out;
446 		case SEMGET:
447 			err = sys_semget(first, (int)second, (int)third);
448 			goto out;
449 		case SEMCTL: {
450 			err = sys_semctl(first, second,
451 					 (int)third | IPC_64,
452 					 (union semun) ptr);
453 			goto out;
454 		}
455 		default:
456 			err = -ENOSYS;
457 			goto out;
458 		};
459 	}
460 	if (call <= MSGCTL) {
461 		switch (call) {
462 		case MSGSND:
463 			err = sys_msgsnd(first, ptr, (size_t)second,
464 					 (int)third);
465 			goto out;
466 		case MSGRCV:
467 			err = sys_msgrcv(first, ptr, (size_t)second, fifth,
468 					 (int)third);
469 			goto out;
470 		case MSGGET:
471 			err = sys_msgget((key_t)first, (int)second);
472 			goto out;
473 		case MSGCTL:
474 			err = sys_msgctl(first, (int)second | IPC_64, ptr);
475 			goto out;
476 		default:
477 			err = -ENOSYS;
478 			goto out;
479 		};
480 	}
481 	if (call <= SHMCTL) {
482 		switch (call) {
483 		case SHMAT: {
484 			ulong raddr;
485 			err = do_shmat(first, ptr, (int)second, &raddr);
486 			if (!err) {
487 				if (put_user(raddr,
488 					     (ulong __user *) third))
489 					err = -EFAULT;
490 			}
491 			goto out;
492 		}
493 		case SHMDT:
494 			err = sys_shmdt(ptr);
495 			goto out;
496 		case SHMGET:
497 			err = sys_shmget(first, (size_t)second, (int)third);
498 			goto out;
499 		case SHMCTL:
500 			err = sys_shmctl(first, (int)second | IPC_64, ptr);
501 			goto out;
502 		default:
503 			err = -ENOSYS;
504 			goto out;
505 		};
506 	} else {
507 		err = -ENOSYS;
508 	}
509 out:
510 	return err;
511 }
512 
513 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
514 {
515 	int ret;
516 
517 	if (current->personality == PER_LINUX32 &&
518 	    personality == PER_LINUX)
519 		personality = PER_LINUX32;
520 	ret = sys_personality(personality);
521 	if (ret == PER_LINUX32)
522 		ret = PER_LINUX;
523 
524 	return ret;
525 }
526 
527 int sparc_mmap_check(unsigned long addr, unsigned long len)
528 {
529 	if (test_thread_flag(TIF_32BIT)) {
530 		if (len >= STACK_TOP32)
531 			return -EINVAL;
532 
533 		if (addr > STACK_TOP32 - len)
534 			return -EINVAL;
535 	} else {
536 		if (len >= VA_EXCLUDE_START)
537 			return -EINVAL;
538 
539 		if (invalid_64bit_range(addr, len))
540 			return -EINVAL;
541 	}
542 
543 	return 0;
544 }
545 
546 /* Linux version of mmap */
547 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
548 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
549 		unsigned long, off)
550 {
551 	unsigned long retval = -EINVAL;
552 
553 	if ((off + PAGE_ALIGN(len)) < off)
554 		goto out;
555 	if (off & ~PAGE_MASK)
556 		goto out;
557 	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
558 out:
559 	return retval;
560 }
561 
562 SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
563 {
564 	long ret;
565 
566 	if (invalid_64bit_range(addr, len))
567 		return -EINVAL;
568 
569 	down_write(&current->mm->mmap_sem);
570 	ret = do_munmap(current->mm, addr, len);
571 	up_write(&current->mm->mmap_sem);
572 	return ret;
573 }
574 
575 extern unsigned long do_mremap(unsigned long addr,
576 	unsigned long old_len, unsigned long new_len,
577 	unsigned long flags, unsigned long new_addr);
578 
579 SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
580 		unsigned long, new_len, unsigned long, flags,
581 		unsigned long, new_addr)
582 {
583 	unsigned long ret = -EINVAL;
584 
585 	if (test_thread_flag(TIF_32BIT))
586 		goto out;
587 
588 	down_write(&current->mm->mmap_sem);
589 	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
590 	up_write(&current->mm->mmap_sem);
591 out:
592 	return ret;
593 }
594 
595 /* we come to here via sys_nis_syscall so it can setup the regs argument */
596 asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
597 {
598 	static int count;
599 
600 	/* Don't make the system unusable, if someone goes stuck */
601 	if (count++ > 5)
602 		return -ENOSYS;
603 
604 	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
605 #ifdef DEBUG_UNIMP_SYSCALL
606 	show_regs (regs);
607 #endif
608 
609 	return -ENOSYS;
610 }
611 
612 /* #define DEBUG_SPARC_BREAKPOINT */
613 
614 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
615 {
616 	siginfo_t info;
617 
618 	if (test_thread_flag(TIF_32BIT)) {
619 		regs->tpc &= 0xffffffff;
620 		regs->tnpc &= 0xffffffff;
621 	}
622 #ifdef DEBUG_SPARC_BREAKPOINT
623         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
624 #endif
625 	info.si_signo = SIGTRAP;
626 	info.si_errno = 0;
627 	info.si_code = TRAP_BRKPT;
628 	info.si_addr = (void __user *)regs->tpc;
629 	info.si_trapno = 0;
630 	force_sig_info(SIGTRAP, &info, current);
631 #ifdef DEBUG_SPARC_BREAKPOINT
632 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
633 #endif
634 }
635 
636 extern void check_pending(int signum);
637 
638 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
639 {
640         int nlen, err;
641 
642 	if (len < 0)
643 		return -EINVAL;
644 
645  	down_read(&uts_sem);
646 
647 	nlen = strlen(utsname()->domainname) + 1;
648 	err = -EINVAL;
649 	if (nlen > len)
650 		goto out;
651 
652 	err = -EFAULT;
653 	if (!copy_to_user(name, utsname()->domainname, nlen))
654 		err = 0;
655 
656 out:
657 	up_read(&uts_sem);
658 	return err;
659 }
660 
661 SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
662 		utrap_handler_t, new_p, utrap_handler_t, new_d,
663 		utrap_handler_t __user *, old_p,
664 		utrap_handler_t __user *, old_d)
665 {
666 	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
667 		return -EINVAL;
668 	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
669 		if (old_p) {
670 			if (!current_thread_info()->utraps) {
671 				if (put_user(NULL, old_p))
672 					return -EFAULT;
673 			} else {
674 				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
675 					return -EFAULT;
676 			}
677 		}
678 		if (old_d) {
679 			if (put_user(NULL, old_d))
680 				return -EFAULT;
681 		}
682 		return 0;
683 	}
684 	if (!current_thread_info()->utraps) {
685 		current_thread_info()->utraps =
686 			kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL);
687 		if (!current_thread_info()->utraps)
688 			return -ENOMEM;
689 		current_thread_info()->utraps[0] = 1;
690 	} else {
691 		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
692 		    current_thread_info()->utraps[0] > 1) {
693 			unsigned long *p = current_thread_info()->utraps;
694 
695 			current_thread_info()->utraps =
696 				kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long),
697 					GFP_KERNEL);
698 			if (!current_thread_info()->utraps) {
699 				current_thread_info()->utraps = p;
700 				return -ENOMEM;
701 			}
702 			p[0]--;
703 			current_thread_info()->utraps[0] = 1;
704 			memcpy(current_thread_info()->utraps+1, p+1,
705 			       UT_TRAP_INSTRUCTION_31*sizeof(long));
706 		}
707 	}
708 	if (old_p) {
709 		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
710 			return -EFAULT;
711 	}
712 	if (old_d) {
713 		if (put_user(NULL, old_d))
714 			return -EFAULT;
715 	}
716 	current_thread_info()->utraps[type] = (long)new_p;
717 
718 	return 0;
719 }
720 
721 asmlinkage long sparc_memory_ordering(unsigned long model,
722 				      struct pt_regs *regs)
723 {
724 	if (model >= 3)
725 		return -EINVAL;
726 	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
727 	return 0;
728 }
729 
730 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
731 		struct sigaction __user *, oact, void __user *, restorer,
732 		size_t, sigsetsize)
733 {
734 	struct k_sigaction new_ka, old_ka;
735 	int ret;
736 
737 	/* XXX: Don't preclude handling different sized sigset_t's.  */
738 	if (sigsetsize != sizeof(sigset_t))
739 		return -EINVAL;
740 
741 	if (act) {
742 		new_ka.ka_restorer = restorer;
743 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
744 			return -EFAULT;
745 	}
746 
747 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
748 
749 	if (!ret && oact) {
750 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
751 			return -EFAULT;
752 	}
753 
754 	return ret;
755 }
756 
757 /*
758  * Do a system call from kernel instead of calling sys_execve so we
759  * end up with proper pt_regs.
760  */
761 int kernel_execve(const char *filename,
762 		  const char *const argv[],
763 		  const char *const envp[])
764 {
765 	long __res;
766 	register long __g1 __asm__ ("g1") = __NR_execve;
767 	register long __o0 __asm__ ("o0") = (long)(filename);
768 	register long __o1 __asm__ ("o1") = (long)(argv);
769 	register long __o2 __asm__ ("o2") = (long)(envp);
770 	asm volatile ("t 0x6d\n\t"
771 		      "sub %%g0, %%o0, %0\n\t"
772 		      "movcc %%xcc, %%o0, %0\n\t"
773 		      : "=r" (__res), "=&r" (__o0)
774 		      : "1" (__o0), "r" (__o1), "r" (__o2), "r" (__g1)
775 		      : "cc");
776 	return __res;
777 }
778