xref: /linux/arch/sparc/kernel/sys_sparc_64.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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/signal.h>
11 #include <linux/sched/mm.h>
12 #include <linux/sched/debug.h>
13 #include <linux/fs.h>
14 #include <linux/file.h>
15 #include <linux/mm.h>
16 #include <linux/sem.h>
17 #include <linux/msg.h>
18 #include <linux/shm.h>
19 #include <linux/stat.h>
20 #include <linux/mman.h>
21 #include <linux/utsname.h>
22 #include <linux/smp.h>
23 #include <linux/slab.h>
24 #include <linux/syscalls.h>
25 #include <linux/ipc.h>
26 #include <linux/personality.h>
27 #include <linux/random.h>
28 #include <linux/export.h>
29 #include <linux/context_tracking.h>
30 
31 #include <linux/uaccess.h>
32 #include <asm/utrap.h>
33 #include <asm/unistd.h>
34 
35 #include "entry.h"
36 #include "kernel.h"
37 #include "systbls.h"
38 
39 /* #define DEBUG_UNIMP_SYSCALL */
40 
41 asmlinkage unsigned long sys_getpagesize(void)
42 {
43 	return PAGE_SIZE;
44 }
45 
46 /* Does addr --> addr+len fall within 4GB of the VA-space hole or
47  * overflow past the end of the 64-bit address space?
48  */
49 static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
50 {
51 	unsigned long va_exclude_start, va_exclude_end;
52 
53 	va_exclude_start = VA_EXCLUDE_START;
54 	va_exclude_end   = VA_EXCLUDE_END;
55 
56 	if (unlikely(len >= va_exclude_start))
57 		return 1;
58 
59 	if (unlikely((addr + len) < addr))
60 		return 1;
61 
62 	if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
63 		     ((addr + len) >= va_exclude_start &&
64 		      (addr + len) < va_exclude_end)))
65 		return 1;
66 
67 	return 0;
68 }
69 
70 /* These functions differ from the default implementations in
71  * mm/mmap.c in two ways:
72  *
73  * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
74  *    for fixed such mappings we just validate what the user gave us.
75  * 2) For 64-bit tasks we avoid mapping anything within 4GB of
76  *    the spitfire/niagara VA-hole.
77  */
78 
79 static inline unsigned long COLOR_ALIGN(unsigned long addr,
80 					 unsigned long pgoff)
81 {
82 	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
83 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
84 
85 	return base + off;
86 }
87 
88 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
89 {
90 	struct mm_struct *mm = current->mm;
91 	struct vm_area_struct * vma;
92 	unsigned long task_size = TASK_SIZE;
93 	int do_color_align;
94 	struct vm_unmapped_area_info info;
95 
96 	if (flags & MAP_FIXED) {
97 		/* We do not accept a shared mapping if it would violate
98 		 * cache aliasing constraints.
99 		 */
100 		if ((flags & MAP_SHARED) &&
101 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
102 			return -EINVAL;
103 		return addr;
104 	}
105 
106 	if (test_thread_flag(TIF_32BIT))
107 		task_size = STACK_TOP32;
108 	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
109 		return -ENOMEM;
110 
111 	do_color_align = 0;
112 	if (filp || (flags & MAP_SHARED))
113 		do_color_align = 1;
114 
115 	if (addr) {
116 		if (do_color_align)
117 			addr = COLOR_ALIGN(addr, pgoff);
118 		else
119 			addr = PAGE_ALIGN(addr);
120 
121 		vma = find_vma(mm, addr);
122 		if (task_size - len >= addr &&
123 		    (!vma || addr + len <= vma->vm_start))
124 			return addr;
125 	}
126 
127 	info.flags = 0;
128 	info.length = len;
129 	info.low_limit = TASK_UNMAPPED_BASE;
130 	info.high_limit = min(task_size, VA_EXCLUDE_START);
131 	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
132 	info.align_offset = pgoff << PAGE_SHIFT;
133 	addr = vm_unmapped_area(&info);
134 
135 	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
136 		VM_BUG_ON(addr != -ENOMEM);
137 		info.low_limit = VA_EXCLUDE_END;
138 		info.high_limit = task_size;
139 		addr = vm_unmapped_area(&info);
140 	}
141 
142 	return addr;
143 }
144 
145 unsigned long
146 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
147 			  const unsigned long len, const unsigned long pgoff,
148 			  const unsigned long flags)
149 {
150 	struct vm_area_struct *vma;
151 	struct mm_struct *mm = current->mm;
152 	unsigned long task_size = STACK_TOP32;
153 	unsigned long addr = addr0;
154 	int do_color_align;
155 	struct vm_unmapped_area_info info;
156 
157 	/* This should only ever run for 32-bit processes.  */
158 	BUG_ON(!test_thread_flag(TIF_32BIT));
159 
160 	if (flags & MAP_FIXED) {
161 		/* We do not accept a shared mapping if it would violate
162 		 * cache aliasing constraints.
163 		 */
164 		if ((flags & MAP_SHARED) &&
165 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
166 			return -EINVAL;
167 		return addr;
168 	}
169 
170 	if (unlikely(len > task_size))
171 		return -ENOMEM;
172 
173 	do_color_align = 0;
174 	if (filp || (flags & MAP_SHARED))
175 		do_color_align = 1;
176 
177 	/* requesting a specific address */
178 	if (addr) {
179 		if (do_color_align)
180 			addr = COLOR_ALIGN(addr, pgoff);
181 		else
182 			addr = PAGE_ALIGN(addr);
183 
184 		vma = find_vma(mm, addr);
185 		if (task_size - len >= addr &&
186 		    (!vma || addr + len <= vma->vm_start))
187 			return addr;
188 	}
189 
190 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
191 	info.length = len;
192 	info.low_limit = PAGE_SIZE;
193 	info.high_limit = mm->mmap_base;
194 	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
195 	info.align_offset = pgoff << PAGE_SHIFT;
196 	addr = vm_unmapped_area(&info);
197 
198 	/*
199 	 * A failed mmap() very likely causes application failure,
200 	 * so fall back to the bottom-up function here. This scenario
201 	 * can happen with large stack limits and large mmap()
202 	 * allocations.
203 	 */
204 	if (addr & ~PAGE_MASK) {
205 		VM_BUG_ON(addr != -ENOMEM);
206 		info.flags = 0;
207 		info.low_limit = TASK_UNMAPPED_BASE;
208 		info.high_limit = STACK_TOP32;
209 		addr = vm_unmapped_area(&info);
210 	}
211 
212 	return addr;
213 }
214 
215 /* Try to align mapping such that we align it as much as possible. */
216 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
217 {
218 	unsigned long align_goal, addr = -ENOMEM;
219 	unsigned long (*get_area)(struct file *, unsigned long,
220 				  unsigned long, unsigned long, unsigned long);
221 
222 	get_area = current->mm->get_unmapped_area;
223 
224 	if (flags & MAP_FIXED) {
225 		/* Ok, don't mess with it. */
226 		return get_area(NULL, orig_addr, len, pgoff, flags);
227 	}
228 	flags &= ~MAP_SHARED;
229 
230 	align_goal = PAGE_SIZE;
231 	if (len >= (4UL * 1024 * 1024))
232 		align_goal = (4UL * 1024 * 1024);
233 	else if (len >= (512UL * 1024))
234 		align_goal = (512UL * 1024);
235 	else if (len >= (64UL * 1024))
236 		align_goal = (64UL * 1024);
237 
238 	do {
239 		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
240 		if (!(addr & ~PAGE_MASK)) {
241 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
242 			break;
243 		}
244 
245 		if (align_goal == (4UL * 1024 * 1024))
246 			align_goal = (512UL * 1024);
247 		else if (align_goal == (512UL * 1024))
248 			align_goal = (64UL * 1024);
249 		else
250 			align_goal = PAGE_SIZE;
251 	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
252 
253 	/* Mapping is smaller than 64K or larger areas could not
254 	 * be obtained.
255 	 */
256 	if (addr & ~PAGE_MASK)
257 		addr = get_area(NULL, orig_addr, len, pgoff, flags);
258 
259 	return addr;
260 }
261 EXPORT_SYMBOL(get_fb_unmapped_area);
262 
263 /* Essentially the same as PowerPC.  */
264 static unsigned long mmap_rnd(void)
265 {
266 	unsigned long rnd = 0UL;
267 
268 	if (current->flags & PF_RANDOMIZE) {
269 		unsigned long val = get_random_long();
270 		if (test_thread_flag(TIF_32BIT))
271 			rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
272 		else
273 			rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
274 	}
275 	return rnd << PAGE_SHIFT;
276 }
277 
278 void arch_pick_mmap_layout(struct mm_struct *mm)
279 {
280 	unsigned long random_factor = mmap_rnd();
281 	unsigned long gap;
282 
283 	/*
284 	 * Fall back to the standard layout if the personality
285 	 * bit is set, or if the expected stack growth is unlimited:
286 	 */
287 	gap = rlimit(RLIMIT_STACK);
288 	if (!test_thread_flag(TIF_32BIT) ||
289 	    (current->personality & ADDR_COMPAT_LAYOUT) ||
290 	    gap == RLIM_INFINITY ||
291 	    sysctl_legacy_va_layout) {
292 		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
293 		mm->get_unmapped_area = arch_get_unmapped_area;
294 	} else {
295 		/* We know it's 32-bit */
296 		unsigned long task_size = STACK_TOP32;
297 
298 		if (gap < 128 * 1024 * 1024)
299 			gap = 128 * 1024 * 1024;
300 		if (gap > (task_size / 6 * 5))
301 			gap = (task_size / 6 * 5);
302 
303 		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
304 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
305 	}
306 }
307 
308 /*
309  * sys_pipe() is the normal C calling standard for creating
310  * a pipe. It's not the way unix traditionally does this, though.
311  */
312 SYSCALL_DEFINE1(sparc_pipe_real, struct pt_regs *, regs)
313 {
314 	int fd[2];
315 	int error;
316 
317 	error = do_pipe_flags(fd, 0);
318 	if (error)
319 		goto out;
320 	regs->u_regs[UREG_I1] = fd[1];
321 	error = fd[0];
322 out:
323 	return error;
324 }
325 
326 /*
327  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
328  *
329  * This is really horribly ugly.
330  */
331 
332 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
333 		unsigned long, third, void __user *, ptr, long, fifth)
334 {
335 	long err;
336 
337 	/* No need for backward compatibility. We can start fresh... */
338 	if (call <= SEMTIMEDOP) {
339 		switch (call) {
340 		case SEMOP:
341 			err = sys_semtimedop(first, ptr,
342 					     (unsigned int)second, NULL);
343 			goto out;
344 		case SEMTIMEDOP:
345 			err = sys_semtimedop(first, ptr, (unsigned int)second,
346 				(const struct timespec __user *)
347 					     (unsigned long) fifth);
348 			goto out;
349 		case SEMGET:
350 			err = sys_semget(first, (int)second, (int)third);
351 			goto out;
352 		case SEMCTL: {
353 			err = sys_semctl(first, second,
354 					 (int)third | IPC_64,
355 					 (unsigned long) ptr);
356 			goto out;
357 		}
358 		default:
359 			err = -ENOSYS;
360 			goto out;
361 		}
362 	}
363 	if (call <= MSGCTL) {
364 		switch (call) {
365 		case MSGSND:
366 			err = sys_msgsnd(first, ptr, (size_t)second,
367 					 (int)third);
368 			goto out;
369 		case MSGRCV:
370 			err = sys_msgrcv(first, ptr, (size_t)second, fifth,
371 					 (int)third);
372 			goto out;
373 		case MSGGET:
374 			err = sys_msgget((key_t)first, (int)second);
375 			goto out;
376 		case MSGCTL:
377 			err = sys_msgctl(first, (int)second | IPC_64, ptr);
378 			goto out;
379 		default:
380 			err = -ENOSYS;
381 			goto out;
382 		}
383 	}
384 	if (call <= SHMCTL) {
385 		switch (call) {
386 		case SHMAT: {
387 			ulong raddr;
388 			err = do_shmat(first, ptr, (int)second, &raddr, SHMLBA);
389 			if (!err) {
390 				if (put_user(raddr,
391 					     (ulong __user *) third))
392 					err = -EFAULT;
393 			}
394 			goto out;
395 		}
396 		case SHMDT:
397 			err = sys_shmdt(ptr);
398 			goto out;
399 		case SHMGET:
400 			err = sys_shmget(first, (size_t)second, (int)third);
401 			goto out;
402 		case SHMCTL:
403 			err = sys_shmctl(first, (int)second | IPC_64, ptr);
404 			goto out;
405 		default:
406 			err = -ENOSYS;
407 			goto out;
408 		}
409 	} else {
410 		err = -ENOSYS;
411 	}
412 out:
413 	return err;
414 }
415 
416 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
417 {
418 	long ret;
419 
420 	if (personality(current->personality) == PER_LINUX32 &&
421 	    personality(personality) == PER_LINUX)
422 		personality |= PER_LINUX32;
423 	ret = sys_personality(personality);
424 	if (personality(ret) == PER_LINUX32)
425 		ret &= ~PER_LINUX32;
426 
427 	return ret;
428 }
429 
430 int sparc_mmap_check(unsigned long addr, unsigned long len)
431 {
432 	if (test_thread_flag(TIF_32BIT)) {
433 		if (len >= STACK_TOP32)
434 			return -EINVAL;
435 
436 		if (addr > STACK_TOP32 - len)
437 			return -EINVAL;
438 	} else {
439 		if (len >= VA_EXCLUDE_START)
440 			return -EINVAL;
441 
442 		if (invalid_64bit_range(addr, len))
443 			return -EINVAL;
444 	}
445 
446 	return 0;
447 }
448 
449 /* Linux version of mmap */
450 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
451 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
452 		unsigned long, off)
453 {
454 	unsigned long retval = -EINVAL;
455 
456 	if ((off + PAGE_ALIGN(len)) < off)
457 		goto out;
458 	if (off & ~PAGE_MASK)
459 		goto out;
460 	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
461 out:
462 	return retval;
463 }
464 
465 SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
466 {
467 	if (invalid_64bit_range(addr, len))
468 		return -EINVAL;
469 
470 	return vm_munmap(addr, len);
471 }
472 
473 SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
474 		unsigned long, new_len, unsigned long, flags,
475 		unsigned long, new_addr)
476 {
477 	if (test_thread_flag(TIF_32BIT))
478 		return -EINVAL;
479 	return sys_mremap(addr, old_len, new_len, flags, new_addr);
480 }
481 
482 /* we come to here via sys_nis_syscall so it can setup the regs argument */
483 asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
484 {
485 	static int count;
486 
487 	/* Don't make the system unusable, if someone goes stuck */
488 	if (count++ > 5)
489 		return -ENOSYS;
490 
491 	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
492 #ifdef DEBUG_UNIMP_SYSCALL
493 	show_regs (regs);
494 #endif
495 
496 	return -ENOSYS;
497 }
498 
499 /* #define DEBUG_SPARC_BREAKPOINT */
500 
501 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
502 {
503 	enum ctx_state prev_state = exception_enter();
504 	siginfo_t info;
505 
506 	if (test_thread_flag(TIF_32BIT)) {
507 		regs->tpc &= 0xffffffff;
508 		regs->tnpc &= 0xffffffff;
509 	}
510 #ifdef DEBUG_SPARC_BREAKPOINT
511         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
512 #endif
513 	info.si_signo = SIGTRAP;
514 	info.si_errno = 0;
515 	info.si_code = TRAP_BRKPT;
516 	info.si_addr = (void __user *)regs->tpc;
517 	info.si_trapno = 0;
518 	force_sig_info(SIGTRAP, &info, current);
519 #ifdef DEBUG_SPARC_BREAKPOINT
520 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
521 #endif
522 	exception_exit(prev_state);
523 }
524 
525 extern void check_pending(int signum);
526 
527 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
528 {
529         int nlen, err;
530 
531 	if (len < 0)
532 		return -EINVAL;
533 
534  	down_read(&uts_sem);
535 
536 	nlen = strlen(utsname()->domainname) + 1;
537 	err = -EINVAL;
538 	if (nlen > len)
539 		goto out;
540 
541 	err = -EFAULT;
542 	if (!copy_to_user(name, utsname()->domainname, nlen))
543 		err = 0;
544 
545 out:
546 	up_read(&uts_sem);
547 	return err;
548 }
549 
550 SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
551 		utrap_handler_t, new_p, utrap_handler_t, new_d,
552 		utrap_handler_t __user *, old_p,
553 		utrap_handler_t __user *, old_d)
554 {
555 	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
556 		return -EINVAL;
557 	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
558 		if (old_p) {
559 			if (!current_thread_info()->utraps) {
560 				if (put_user(NULL, old_p))
561 					return -EFAULT;
562 			} else {
563 				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
564 					return -EFAULT;
565 			}
566 		}
567 		if (old_d) {
568 			if (put_user(NULL, old_d))
569 				return -EFAULT;
570 		}
571 		return 0;
572 	}
573 	if (!current_thread_info()->utraps) {
574 		current_thread_info()->utraps =
575 			kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL);
576 		if (!current_thread_info()->utraps)
577 			return -ENOMEM;
578 		current_thread_info()->utraps[0] = 1;
579 	} else {
580 		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
581 		    current_thread_info()->utraps[0] > 1) {
582 			unsigned long *p = current_thread_info()->utraps;
583 
584 			current_thread_info()->utraps =
585 				kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long),
586 					GFP_KERNEL);
587 			if (!current_thread_info()->utraps) {
588 				current_thread_info()->utraps = p;
589 				return -ENOMEM;
590 			}
591 			p[0]--;
592 			current_thread_info()->utraps[0] = 1;
593 			memcpy(current_thread_info()->utraps+1, p+1,
594 			       UT_TRAP_INSTRUCTION_31*sizeof(long));
595 		}
596 	}
597 	if (old_p) {
598 		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
599 			return -EFAULT;
600 	}
601 	if (old_d) {
602 		if (put_user(NULL, old_d))
603 			return -EFAULT;
604 	}
605 	current_thread_info()->utraps[type] = (long)new_p;
606 
607 	return 0;
608 }
609 
610 asmlinkage long sparc_memory_ordering(unsigned long model,
611 				      struct pt_regs *regs)
612 {
613 	if (model >= 3)
614 		return -EINVAL;
615 	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
616 	return 0;
617 }
618 
619 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
620 		struct sigaction __user *, oact, void __user *, restorer,
621 		size_t, sigsetsize)
622 {
623 	struct k_sigaction new_ka, old_ka;
624 	int ret;
625 
626 	/* XXX: Don't preclude handling different sized sigset_t's.  */
627 	if (sigsetsize != sizeof(sigset_t))
628 		return -EINVAL;
629 
630 	if (act) {
631 		new_ka.ka_restorer = restorer;
632 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
633 			return -EFAULT;
634 	}
635 
636 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
637 
638 	if (!ret && oact) {
639 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
640 			return -EFAULT;
641 	}
642 
643 	return ret;
644 }
645 
646 asmlinkage long sys_kern_features(void)
647 {
648 	return KERN_FEATURE_MIXED_MODE_STACK;
649 }
650