xref: /openbmc/linux/arch/sparc/kernel/sys_sparc_64.c (revision 12eb4683)
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 #include <linux/context_tracking.h>
28 
29 #include <asm/uaccess.h>
30 #include <asm/utrap.h>
31 #include <asm/unistd.h>
32 
33 #include "entry.h"
34 #include "systbls.h"
35 
36 /* #define DEBUG_UNIMP_SYSCALL */
37 
38 asmlinkage unsigned long sys_getpagesize(void)
39 {
40 	return PAGE_SIZE;
41 }
42 
43 /* Does addr --> addr+len fall within 4GB of the VA-space hole or
44  * overflow past the end of the 64-bit address space?
45  */
46 static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
47 {
48 	unsigned long va_exclude_start, va_exclude_end;
49 
50 	va_exclude_start = VA_EXCLUDE_START;
51 	va_exclude_end   = VA_EXCLUDE_END;
52 
53 	if (unlikely(len >= va_exclude_start))
54 		return 1;
55 
56 	if (unlikely((addr + len) < addr))
57 		return 1;
58 
59 	if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
60 		     ((addr + len) >= va_exclude_start &&
61 		      (addr + len) < va_exclude_end)))
62 		return 1;
63 
64 	return 0;
65 }
66 
67 /* These functions differ from the default implementations in
68  * mm/mmap.c in two ways:
69  *
70  * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
71  *    for fixed such mappings we just validate what the user gave us.
72  * 2) For 64-bit tasks we avoid mapping anything within 4GB of
73  *    the spitfire/niagara VA-hole.
74  */
75 
76 static inline unsigned long COLOR_ALIGN(unsigned long addr,
77 					 unsigned long pgoff)
78 {
79 	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
80 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
81 
82 	return base + off;
83 }
84 
85 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
86 {
87 	struct mm_struct *mm = current->mm;
88 	struct vm_area_struct * vma;
89 	unsigned long task_size = TASK_SIZE;
90 	int do_color_align;
91 	struct vm_unmapped_area_info info;
92 
93 	if (flags & MAP_FIXED) {
94 		/* We do not accept a shared mapping if it would violate
95 		 * cache aliasing constraints.
96 		 */
97 		if ((flags & MAP_SHARED) &&
98 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
99 			return -EINVAL;
100 		return addr;
101 	}
102 
103 	if (test_thread_flag(TIF_32BIT))
104 		task_size = STACK_TOP32;
105 	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
106 		return -ENOMEM;
107 
108 	do_color_align = 0;
109 	if (filp || (flags & MAP_SHARED))
110 		do_color_align = 1;
111 
112 	if (addr) {
113 		if (do_color_align)
114 			addr = COLOR_ALIGN(addr, pgoff);
115 		else
116 			addr = PAGE_ALIGN(addr);
117 
118 		vma = find_vma(mm, addr);
119 		if (task_size - len >= addr &&
120 		    (!vma || addr + len <= vma->vm_start))
121 			return addr;
122 	}
123 
124 	info.flags = 0;
125 	info.length = len;
126 	info.low_limit = TASK_UNMAPPED_BASE;
127 	info.high_limit = min(task_size, VA_EXCLUDE_START);
128 	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
129 	info.align_offset = pgoff << PAGE_SHIFT;
130 	addr = vm_unmapped_area(&info);
131 
132 	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
133 		VM_BUG_ON(addr != -ENOMEM);
134 		info.low_limit = VA_EXCLUDE_END;
135 		info.high_limit = task_size;
136 		addr = vm_unmapped_area(&info);
137 	}
138 
139 	return addr;
140 }
141 
142 unsigned long
143 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
144 			  const unsigned long len, const unsigned long pgoff,
145 			  const unsigned long flags)
146 {
147 	struct vm_area_struct *vma;
148 	struct mm_struct *mm = current->mm;
149 	unsigned long task_size = STACK_TOP32;
150 	unsigned long addr = addr0;
151 	int do_color_align;
152 	struct vm_unmapped_area_info info;
153 
154 	/* This should only ever run for 32-bit processes.  */
155 	BUG_ON(!test_thread_flag(TIF_32BIT));
156 
157 	if (flags & MAP_FIXED) {
158 		/* We do not accept a shared mapping if it would violate
159 		 * cache aliasing constraints.
160 		 */
161 		if ((flags & MAP_SHARED) &&
162 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
163 			return -EINVAL;
164 		return addr;
165 	}
166 
167 	if (unlikely(len > task_size))
168 		return -ENOMEM;
169 
170 	do_color_align = 0;
171 	if (filp || (flags & MAP_SHARED))
172 		do_color_align = 1;
173 
174 	/* requesting a specific address */
175 	if (addr) {
176 		if (do_color_align)
177 			addr = COLOR_ALIGN(addr, pgoff);
178 		else
179 			addr = PAGE_ALIGN(addr);
180 
181 		vma = find_vma(mm, addr);
182 		if (task_size - len >= addr &&
183 		    (!vma || addr + len <= vma->vm_start))
184 			return addr;
185 	}
186 
187 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
188 	info.length = len;
189 	info.low_limit = PAGE_SIZE;
190 	info.high_limit = mm->mmap_base;
191 	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
192 	info.align_offset = pgoff << PAGE_SHIFT;
193 	addr = vm_unmapped_area(&info);
194 
195 	/*
196 	 * A failed mmap() very likely causes application failure,
197 	 * so fall back to the bottom-up function here. This scenario
198 	 * can happen with large stack limits and large mmap()
199 	 * allocations.
200 	 */
201 	if (addr & ~PAGE_MASK) {
202 		VM_BUG_ON(addr != -ENOMEM);
203 		info.flags = 0;
204 		info.low_limit = TASK_UNMAPPED_BASE;
205 		info.high_limit = STACK_TOP32;
206 		addr = vm_unmapped_area(&info);
207 	}
208 
209 	return addr;
210 }
211 
212 /* Try to align mapping such that we align it as much as possible. */
213 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
214 {
215 	unsigned long align_goal, addr = -ENOMEM;
216 	unsigned long (*get_area)(struct file *, unsigned long,
217 				  unsigned long, unsigned long, unsigned long);
218 
219 	get_area = current->mm->get_unmapped_area;
220 
221 	if (flags & MAP_FIXED) {
222 		/* Ok, don't mess with it. */
223 		return get_area(NULL, orig_addr, len, pgoff, flags);
224 	}
225 	flags &= ~MAP_SHARED;
226 
227 	align_goal = PAGE_SIZE;
228 	if (len >= (4UL * 1024 * 1024))
229 		align_goal = (4UL * 1024 * 1024);
230 	else if (len >= (512UL * 1024))
231 		align_goal = (512UL * 1024);
232 	else if (len >= (64UL * 1024))
233 		align_goal = (64UL * 1024);
234 
235 	do {
236 		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
237 		if (!(addr & ~PAGE_MASK)) {
238 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
239 			break;
240 		}
241 
242 		if (align_goal == (4UL * 1024 * 1024))
243 			align_goal = (512UL * 1024);
244 		else if (align_goal == (512UL * 1024))
245 			align_goal = (64UL * 1024);
246 		else
247 			align_goal = PAGE_SIZE;
248 	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
249 
250 	/* Mapping is smaller than 64K or larger areas could not
251 	 * be obtained.
252 	 */
253 	if (addr & ~PAGE_MASK)
254 		addr = get_area(NULL, orig_addr, len, pgoff, flags);
255 
256 	return addr;
257 }
258 EXPORT_SYMBOL(get_fb_unmapped_area);
259 
260 /* Essentially the same as PowerPC.  */
261 static unsigned long mmap_rnd(void)
262 {
263 	unsigned long rnd = 0UL;
264 
265 	if (current->flags & PF_RANDOMIZE) {
266 		unsigned long val = get_random_int();
267 		if (test_thread_flag(TIF_32BIT))
268 			rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
269 		else
270 			rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
271 	}
272 	return rnd << PAGE_SHIFT;
273 }
274 
275 void arch_pick_mmap_layout(struct mm_struct *mm)
276 {
277 	unsigned long random_factor = mmap_rnd();
278 	unsigned long gap;
279 
280 	/*
281 	 * Fall back to the standard layout if the personality
282 	 * bit is set, or if the expected stack growth is unlimited:
283 	 */
284 	gap = rlimit(RLIMIT_STACK);
285 	if (!test_thread_flag(TIF_32BIT) ||
286 	    (current->personality & ADDR_COMPAT_LAYOUT) ||
287 	    gap == RLIM_INFINITY ||
288 	    sysctl_legacy_va_layout) {
289 		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
290 		mm->get_unmapped_area = arch_get_unmapped_area;
291 	} else {
292 		/* We know it's 32-bit */
293 		unsigned long task_size = STACK_TOP32;
294 
295 		if (gap < 128 * 1024 * 1024)
296 			gap = 128 * 1024 * 1024;
297 		if (gap > (task_size / 6 * 5))
298 			gap = (task_size / 6 * 5);
299 
300 		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
301 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
302 	}
303 }
304 
305 /*
306  * sys_pipe() is the normal C calling standard for creating
307  * a pipe. It's not the way unix traditionally does this, though.
308  */
309 SYSCALL_DEFINE1(sparc_pipe_real, struct pt_regs *, regs)
310 {
311 	int fd[2];
312 	int error;
313 
314 	error = do_pipe_flags(fd, 0);
315 	if (error)
316 		goto out;
317 	regs->u_regs[UREG_I1] = fd[1];
318 	error = fd[0];
319 out:
320 	return error;
321 }
322 
323 /*
324  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
325  *
326  * This is really horribly ugly.
327  */
328 
329 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
330 		unsigned long, third, void __user *, ptr, long, fifth)
331 {
332 	long err;
333 
334 	/* No need for backward compatibility. We can start fresh... */
335 	if (call <= SEMCTL) {
336 		switch (call) {
337 		case SEMOP:
338 			err = sys_semtimedop(first, ptr,
339 					     (unsigned)second, NULL);
340 			goto out;
341 		case SEMTIMEDOP:
342 			err = sys_semtimedop(first, ptr, (unsigned)second,
343 				(const struct timespec __user *)
344 					     (unsigned long) fifth);
345 			goto out;
346 		case SEMGET:
347 			err = sys_semget(first, (int)second, (int)third);
348 			goto out;
349 		case SEMCTL: {
350 			err = sys_semctl(first, second,
351 					 (int)third | IPC_64,
352 					 (unsigned long) ptr);
353 			goto out;
354 		}
355 		default:
356 			err = -ENOSYS;
357 			goto out;
358 		}
359 	}
360 	if (call <= MSGCTL) {
361 		switch (call) {
362 		case MSGSND:
363 			err = sys_msgsnd(first, ptr, (size_t)second,
364 					 (int)third);
365 			goto out;
366 		case MSGRCV:
367 			err = sys_msgrcv(first, ptr, (size_t)second, fifth,
368 					 (int)third);
369 			goto out;
370 		case MSGGET:
371 			err = sys_msgget((key_t)first, (int)second);
372 			goto out;
373 		case MSGCTL:
374 			err = sys_msgctl(first, (int)second | IPC_64, ptr);
375 			goto out;
376 		default:
377 			err = -ENOSYS;
378 			goto out;
379 		}
380 	}
381 	if (call <= SHMCTL) {
382 		switch (call) {
383 		case SHMAT: {
384 			ulong raddr;
385 			err = do_shmat(first, ptr, (int)second, &raddr, SHMLBA);
386 			if (!err) {
387 				if (put_user(raddr,
388 					     (ulong __user *) third))
389 					err = -EFAULT;
390 			}
391 			goto out;
392 		}
393 		case SHMDT:
394 			err = sys_shmdt(ptr);
395 			goto out;
396 		case SHMGET:
397 			err = sys_shmget(first, (size_t)second, (int)third);
398 			goto out;
399 		case SHMCTL:
400 			err = sys_shmctl(first, (int)second | IPC_64, ptr);
401 			goto out;
402 		default:
403 			err = -ENOSYS;
404 			goto out;
405 		}
406 	} else {
407 		err = -ENOSYS;
408 	}
409 out:
410 	return err;
411 }
412 
413 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
414 {
415 	int ret;
416 
417 	if (personality(current->personality) == PER_LINUX32 &&
418 	    personality(personality) == PER_LINUX)
419 		personality |= PER_LINUX32;
420 	ret = sys_personality(personality);
421 	if (personality(ret) == PER_LINUX32)
422 		ret &= ~PER_LINUX32;
423 
424 	return ret;
425 }
426 
427 int sparc_mmap_check(unsigned long addr, unsigned long len)
428 {
429 	if (test_thread_flag(TIF_32BIT)) {
430 		if (len >= STACK_TOP32)
431 			return -EINVAL;
432 
433 		if (addr > STACK_TOP32 - len)
434 			return -EINVAL;
435 	} else {
436 		if (len >= VA_EXCLUDE_START)
437 			return -EINVAL;
438 
439 		if (invalid_64bit_range(addr, len))
440 			return -EINVAL;
441 	}
442 
443 	return 0;
444 }
445 
446 /* Linux version of mmap */
447 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
448 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
449 		unsigned long, off)
450 {
451 	unsigned long retval = -EINVAL;
452 
453 	if ((off + PAGE_ALIGN(len)) < off)
454 		goto out;
455 	if (off & ~PAGE_MASK)
456 		goto out;
457 	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
458 out:
459 	return retval;
460 }
461 
462 SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
463 {
464 	if (invalid_64bit_range(addr, len))
465 		return -EINVAL;
466 
467 	return vm_munmap(addr, len);
468 }
469 
470 SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
471 		unsigned long, new_len, unsigned long, flags,
472 		unsigned long, new_addr)
473 {
474 	if (test_thread_flag(TIF_32BIT))
475 		return -EINVAL;
476 	return sys_mremap(addr, old_len, new_len, flags, new_addr);
477 }
478 
479 /* we come to here via sys_nis_syscall so it can setup the regs argument */
480 asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
481 {
482 	static int count;
483 
484 	/* Don't make the system unusable, if someone goes stuck */
485 	if (count++ > 5)
486 		return -ENOSYS;
487 
488 	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
489 #ifdef DEBUG_UNIMP_SYSCALL
490 	show_regs (regs);
491 #endif
492 
493 	return -ENOSYS;
494 }
495 
496 /* #define DEBUG_SPARC_BREAKPOINT */
497 
498 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
499 {
500 	enum ctx_state prev_state = exception_enter();
501 	siginfo_t info;
502 
503 	if (test_thread_flag(TIF_32BIT)) {
504 		regs->tpc &= 0xffffffff;
505 		regs->tnpc &= 0xffffffff;
506 	}
507 #ifdef DEBUG_SPARC_BREAKPOINT
508         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
509 #endif
510 	info.si_signo = SIGTRAP;
511 	info.si_errno = 0;
512 	info.si_code = TRAP_BRKPT;
513 	info.si_addr = (void __user *)regs->tpc;
514 	info.si_trapno = 0;
515 	force_sig_info(SIGTRAP, &info, current);
516 #ifdef DEBUG_SPARC_BREAKPOINT
517 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
518 #endif
519 	exception_exit(prev_state);
520 }
521 
522 extern void check_pending(int signum);
523 
524 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
525 {
526         int nlen, err;
527 
528 	if (len < 0)
529 		return -EINVAL;
530 
531  	down_read(&uts_sem);
532 
533 	nlen = strlen(utsname()->domainname) + 1;
534 	err = -EINVAL;
535 	if (nlen > len)
536 		goto out;
537 
538 	err = -EFAULT;
539 	if (!copy_to_user(name, utsname()->domainname, nlen))
540 		err = 0;
541 
542 out:
543 	up_read(&uts_sem);
544 	return err;
545 }
546 
547 SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
548 		utrap_handler_t, new_p, utrap_handler_t, new_d,
549 		utrap_handler_t __user *, old_p,
550 		utrap_handler_t __user *, old_d)
551 {
552 	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
553 		return -EINVAL;
554 	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
555 		if (old_p) {
556 			if (!current_thread_info()->utraps) {
557 				if (put_user(NULL, old_p))
558 					return -EFAULT;
559 			} else {
560 				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
561 					return -EFAULT;
562 			}
563 		}
564 		if (old_d) {
565 			if (put_user(NULL, old_d))
566 				return -EFAULT;
567 		}
568 		return 0;
569 	}
570 	if (!current_thread_info()->utraps) {
571 		current_thread_info()->utraps =
572 			kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL);
573 		if (!current_thread_info()->utraps)
574 			return -ENOMEM;
575 		current_thread_info()->utraps[0] = 1;
576 	} else {
577 		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
578 		    current_thread_info()->utraps[0] > 1) {
579 			unsigned long *p = current_thread_info()->utraps;
580 
581 			current_thread_info()->utraps =
582 				kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long),
583 					GFP_KERNEL);
584 			if (!current_thread_info()->utraps) {
585 				current_thread_info()->utraps = p;
586 				return -ENOMEM;
587 			}
588 			p[0]--;
589 			current_thread_info()->utraps[0] = 1;
590 			memcpy(current_thread_info()->utraps+1, p+1,
591 			       UT_TRAP_INSTRUCTION_31*sizeof(long));
592 		}
593 	}
594 	if (old_p) {
595 		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
596 			return -EFAULT;
597 	}
598 	if (old_d) {
599 		if (put_user(NULL, old_d))
600 			return -EFAULT;
601 	}
602 	current_thread_info()->utraps[type] = (long)new_p;
603 
604 	return 0;
605 }
606 
607 asmlinkage long sparc_memory_ordering(unsigned long model,
608 				      struct pt_regs *regs)
609 {
610 	if (model >= 3)
611 		return -EINVAL;
612 	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
613 	return 0;
614 }
615 
616 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
617 		struct sigaction __user *, oact, void __user *, restorer,
618 		size_t, sigsetsize)
619 {
620 	struct k_sigaction new_ka, old_ka;
621 	int ret;
622 
623 	/* XXX: Don't preclude handling different sized sigset_t's.  */
624 	if (sigsetsize != sizeof(sigset_t))
625 		return -EINVAL;
626 
627 	if (act) {
628 		new_ka.ka_restorer = restorer;
629 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
630 			return -EFAULT;
631 	}
632 
633 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
634 
635 	if (!ret && oact) {
636 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
637 			return -EFAULT;
638 	}
639 
640 	return ret;
641 }
642 
643 asmlinkage long sys_kern_features(void)
644 {
645 	return KERN_FEATURE_MIXED_MODE_STACK;
646 }
647