xref: /openbmc/linux/arch/sparc/kernel/sys_sparc_64.c (revision 293d5b43)
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 "kernel.h"
35 #include "systbls.h"
36 
37 /* #define DEBUG_UNIMP_SYSCALL */
38 
39 asmlinkage unsigned long sys_getpagesize(void)
40 {
41 	return PAGE_SIZE;
42 }
43 
44 /* Does addr --> addr+len fall within 4GB of the VA-space hole or
45  * overflow past the end of the 64-bit address space?
46  */
47 static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
48 {
49 	unsigned long va_exclude_start, va_exclude_end;
50 
51 	va_exclude_start = VA_EXCLUDE_START;
52 	va_exclude_end   = VA_EXCLUDE_END;
53 
54 	if (unlikely(len >= va_exclude_start))
55 		return 1;
56 
57 	if (unlikely((addr + len) < addr))
58 		return 1;
59 
60 	if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) ||
61 		     ((addr + len) >= va_exclude_start &&
62 		      (addr + len) < va_exclude_end)))
63 		return 1;
64 
65 	return 0;
66 }
67 
68 /* These functions differ from the default implementations in
69  * mm/mmap.c in two ways:
70  *
71  * 1) For file backed MAP_SHARED mmap()'s we D-cache color align,
72  *    for fixed such mappings we just validate what the user gave us.
73  * 2) For 64-bit tasks we avoid mapping anything within 4GB of
74  *    the spitfire/niagara VA-hole.
75  */
76 
77 static inline unsigned long COLOR_ALIGN(unsigned long addr,
78 					 unsigned long pgoff)
79 {
80 	unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1);
81 	unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1);
82 
83 	return base + off;
84 }
85 
86 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
87 {
88 	struct mm_struct *mm = current->mm;
89 	struct vm_area_struct * vma;
90 	unsigned long task_size = TASK_SIZE;
91 	int do_color_align;
92 	struct vm_unmapped_area_info info;
93 
94 	if (flags & MAP_FIXED) {
95 		/* We do not accept a shared mapping if it would violate
96 		 * cache aliasing constraints.
97 		 */
98 		if ((flags & MAP_SHARED) &&
99 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
100 			return -EINVAL;
101 		return addr;
102 	}
103 
104 	if (test_thread_flag(TIF_32BIT))
105 		task_size = STACK_TOP32;
106 	if (unlikely(len > task_size || len >= VA_EXCLUDE_START))
107 		return -ENOMEM;
108 
109 	do_color_align = 0;
110 	if (filp || (flags & MAP_SHARED))
111 		do_color_align = 1;
112 
113 	if (addr) {
114 		if (do_color_align)
115 			addr = COLOR_ALIGN(addr, pgoff);
116 		else
117 			addr = PAGE_ALIGN(addr);
118 
119 		vma = find_vma(mm, addr);
120 		if (task_size - len >= addr &&
121 		    (!vma || addr + len <= vma->vm_start))
122 			return addr;
123 	}
124 
125 	info.flags = 0;
126 	info.length = len;
127 	info.low_limit = TASK_UNMAPPED_BASE;
128 	info.high_limit = min(task_size, VA_EXCLUDE_START);
129 	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
130 	info.align_offset = pgoff << PAGE_SHIFT;
131 	addr = vm_unmapped_area(&info);
132 
133 	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
134 		VM_BUG_ON(addr != -ENOMEM);
135 		info.low_limit = VA_EXCLUDE_END;
136 		info.high_limit = task_size;
137 		addr = vm_unmapped_area(&info);
138 	}
139 
140 	return addr;
141 }
142 
143 unsigned long
144 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
145 			  const unsigned long len, const unsigned long pgoff,
146 			  const unsigned long flags)
147 {
148 	struct vm_area_struct *vma;
149 	struct mm_struct *mm = current->mm;
150 	unsigned long task_size = STACK_TOP32;
151 	unsigned long addr = addr0;
152 	int do_color_align;
153 	struct vm_unmapped_area_info info;
154 
155 	/* This should only ever run for 32-bit processes.  */
156 	BUG_ON(!test_thread_flag(TIF_32BIT));
157 
158 	if (flags & MAP_FIXED) {
159 		/* We do not accept a shared mapping if it would violate
160 		 * cache aliasing constraints.
161 		 */
162 		if ((flags & MAP_SHARED) &&
163 		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
164 			return -EINVAL;
165 		return addr;
166 	}
167 
168 	if (unlikely(len > task_size))
169 		return -ENOMEM;
170 
171 	do_color_align = 0;
172 	if (filp || (flags & MAP_SHARED))
173 		do_color_align = 1;
174 
175 	/* requesting a specific address */
176 	if (addr) {
177 		if (do_color_align)
178 			addr = COLOR_ALIGN(addr, pgoff);
179 		else
180 			addr = PAGE_ALIGN(addr);
181 
182 		vma = find_vma(mm, addr);
183 		if (task_size - len >= addr &&
184 		    (!vma || addr + len <= vma->vm_start))
185 			return addr;
186 	}
187 
188 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
189 	info.length = len;
190 	info.low_limit = PAGE_SIZE;
191 	info.high_limit = mm->mmap_base;
192 	info.align_mask = do_color_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
193 	info.align_offset = pgoff << PAGE_SHIFT;
194 	addr = vm_unmapped_area(&info);
195 
196 	/*
197 	 * A failed mmap() very likely causes application failure,
198 	 * so fall back to the bottom-up function here. This scenario
199 	 * can happen with large stack limits and large mmap()
200 	 * allocations.
201 	 */
202 	if (addr & ~PAGE_MASK) {
203 		VM_BUG_ON(addr != -ENOMEM);
204 		info.flags = 0;
205 		info.low_limit = TASK_UNMAPPED_BASE;
206 		info.high_limit = STACK_TOP32;
207 		addr = vm_unmapped_area(&info);
208 	}
209 
210 	return addr;
211 }
212 
213 /* Try to align mapping such that we align it as much as possible. */
214 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
215 {
216 	unsigned long align_goal, addr = -ENOMEM;
217 	unsigned long (*get_area)(struct file *, unsigned long,
218 				  unsigned long, unsigned long, unsigned long);
219 
220 	get_area = current->mm->get_unmapped_area;
221 
222 	if (flags & MAP_FIXED) {
223 		/* Ok, don't mess with it. */
224 		return get_area(NULL, orig_addr, len, pgoff, flags);
225 	}
226 	flags &= ~MAP_SHARED;
227 
228 	align_goal = PAGE_SIZE;
229 	if (len >= (4UL * 1024 * 1024))
230 		align_goal = (4UL * 1024 * 1024);
231 	else if (len >= (512UL * 1024))
232 		align_goal = (512UL * 1024);
233 	else if (len >= (64UL * 1024))
234 		align_goal = (64UL * 1024);
235 
236 	do {
237 		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
238 		if (!(addr & ~PAGE_MASK)) {
239 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
240 			break;
241 		}
242 
243 		if (align_goal == (4UL * 1024 * 1024))
244 			align_goal = (512UL * 1024);
245 		else if (align_goal == (512UL * 1024))
246 			align_goal = (64UL * 1024);
247 		else
248 			align_goal = PAGE_SIZE;
249 	} while ((addr & ~PAGE_MASK) && align_goal > PAGE_SIZE);
250 
251 	/* Mapping is smaller than 64K or larger areas could not
252 	 * be obtained.
253 	 */
254 	if (addr & ~PAGE_MASK)
255 		addr = get_area(NULL, orig_addr, len, pgoff, flags);
256 
257 	return addr;
258 }
259 EXPORT_SYMBOL(get_fb_unmapped_area);
260 
261 /* Essentially the same as PowerPC.  */
262 static unsigned long mmap_rnd(void)
263 {
264 	unsigned long rnd = 0UL;
265 
266 	if (current->flags & PF_RANDOMIZE) {
267 		unsigned long val = get_random_long();
268 		if (test_thread_flag(TIF_32BIT))
269 			rnd = (val % (1UL << (23UL-PAGE_SHIFT)));
270 		else
271 			rnd = (val % (1UL << (30UL-PAGE_SHIFT)));
272 	}
273 	return rnd << PAGE_SHIFT;
274 }
275 
276 void arch_pick_mmap_layout(struct mm_struct *mm)
277 {
278 	unsigned long random_factor = mmap_rnd();
279 	unsigned long gap;
280 
281 	/*
282 	 * Fall back to the standard layout if the personality
283 	 * bit is set, or if the expected stack growth is unlimited:
284 	 */
285 	gap = rlimit(RLIMIT_STACK);
286 	if (!test_thread_flag(TIF_32BIT) ||
287 	    (current->personality & ADDR_COMPAT_LAYOUT) ||
288 	    gap == RLIM_INFINITY ||
289 	    sysctl_legacy_va_layout) {
290 		mm->mmap_base = TASK_UNMAPPED_BASE + random_factor;
291 		mm->get_unmapped_area = arch_get_unmapped_area;
292 	} else {
293 		/* We know it's 32-bit */
294 		unsigned long task_size = STACK_TOP32;
295 
296 		if (gap < 128 * 1024 * 1024)
297 			gap = 128 * 1024 * 1024;
298 		if (gap > (task_size / 6 * 5))
299 			gap = (task_size / 6 * 5);
300 
301 		mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor);
302 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
303 	}
304 }
305 
306 /*
307  * sys_pipe() is the normal C calling standard for creating
308  * a pipe. It's not the way unix traditionally does this, though.
309  */
310 SYSCALL_DEFINE1(sparc_pipe_real, struct pt_regs *, regs)
311 {
312 	int fd[2];
313 	int error;
314 
315 	error = do_pipe_flags(fd, 0);
316 	if (error)
317 		goto out;
318 	regs->u_regs[UREG_I1] = fd[1];
319 	error = fd[0];
320 out:
321 	return error;
322 }
323 
324 /*
325  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
326  *
327  * This is really horribly ugly.
328  */
329 
330 SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second,
331 		unsigned long, third, void __user *, ptr, long, fifth)
332 {
333 	long err;
334 
335 	/* No need for backward compatibility. We can start fresh... */
336 	if (call <= SEMTIMEDOP) {
337 		switch (call) {
338 		case SEMOP:
339 			err = sys_semtimedop(first, ptr,
340 					     (unsigned int)second, NULL);
341 			goto out;
342 		case SEMTIMEDOP:
343 			err = sys_semtimedop(first, ptr, (unsigned int)second,
344 				(const struct timespec __user *)
345 					     (unsigned long) fifth);
346 			goto out;
347 		case SEMGET:
348 			err = sys_semget(first, (int)second, (int)third);
349 			goto out;
350 		case SEMCTL: {
351 			err = sys_semctl(first, second,
352 					 (int)third | IPC_64,
353 					 (unsigned long) ptr);
354 			goto out;
355 		}
356 		default:
357 			err = -ENOSYS;
358 			goto out;
359 		}
360 	}
361 	if (call <= MSGCTL) {
362 		switch (call) {
363 		case MSGSND:
364 			err = sys_msgsnd(first, ptr, (size_t)second,
365 					 (int)third);
366 			goto out;
367 		case MSGRCV:
368 			err = sys_msgrcv(first, ptr, (size_t)second, fifth,
369 					 (int)third);
370 			goto out;
371 		case MSGGET:
372 			err = sys_msgget((key_t)first, (int)second);
373 			goto out;
374 		case MSGCTL:
375 			err = sys_msgctl(first, (int)second | IPC_64, ptr);
376 			goto out;
377 		default:
378 			err = -ENOSYS;
379 			goto out;
380 		}
381 	}
382 	if (call <= SHMCTL) {
383 		switch (call) {
384 		case SHMAT: {
385 			ulong raddr;
386 			err = do_shmat(first, ptr, (int)second, &raddr, SHMLBA);
387 			if (!err) {
388 				if (put_user(raddr,
389 					     (ulong __user *) third))
390 					err = -EFAULT;
391 			}
392 			goto out;
393 		}
394 		case SHMDT:
395 			err = sys_shmdt(ptr);
396 			goto out;
397 		case SHMGET:
398 			err = sys_shmget(first, (size_t)second, (int)third);
399 			goto out;
400 		case SHMCTL:
401 			err = sys_shmctl(first, (int)second | IPC_64, ptr);
402 			goto out;
403 		default:
404 			err = -ENOSYS;
405 			goto out;
406 		}
407 	} else {
408 		err = -ENOSYS;
409 	}
410 out:
411 	return err;
412 }
413 
414 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
415 {
416 	long ret;
417 
418 	if (personality(current->personality) == PER_LINUX32 &&
419 	    personality(personality) == PER_LINUX)
420 		personality |= PER_LINUX32;
421 	ret = sys_personality(personality);
422 	if (personality(ret) == PER_LINUX32)
423 		ret &= ~PER_LINUX32;
424 
425 	return ret;
426 }
427 
428 int sparc_mmap_check(unsigned long addr, unsigned long len)
429 {
430 	if (test_thread_flag(TIF_32BIT)) {
431 		if (len >= STACK_TOP32)
432 			return -EINVAL;
433 
434 		if (addr > STACK_TOP32 - len)
435 			return -EINVAL;
436 	} else {
437 		if (len >= VA_EXCLUDE_START)
438 			return -EINVAL;
439 
440 		if (invalid_64bit_range(addr, len))
441 			return -EINVAL;
442 	}
443 
444 	return 0;
445 }
446 
447 /* Linux version of mmap */
448 SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
449 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
450 		unsigned long, off)
451 {
452 	unsigned long retval = -EINVAL;
453 
454 	if ((off + PAGE_ALIGN(len)) < off)
455 		goto out;
456 	if (off & ~PAGE_MASK)
457 		goto out;
458 	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
459 out:
460 	return retval;
461 }
462 
463 SYSCALL_DEFINE2(64_munmap, unsigned long, addr, size_t, len)
464 {
465 	if (invalid_64bit_range(addr, len))
466 		return -EINVAL;
467 
468 	return vm_munmap(addr, len);
469 }
470 
471 SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
472 		unsigned long, new_len, unsigned long, flags,
473 		unsigned long, new_addr)
474 {
475 	if (test_thread_flag(TIF_32BIT))
476 		return -EINVAL;
477 	return sys_mremap(addr, old_len, new_len, flags, new_addr);
478 }
479 
480 /* we come to here via sys_nis_syscall so it can setup the regs argument */
481 asmlinkage unsigned long c_sys_nis_syscall(struct pt_regs *regs)
482 {
483 	static int count;
484 
485 	/* Don't make the system unusable, if someone goes stuck */
486 	if (count++ > 5)
487 		return -ENOSYS;
488 
489 	printk ("Unimplemented SPARC system call %ld\n",regs->u_regs[1]);
490 #ifdef DEBUG_UNIMP_SYSCALL
491 	show_regs (regs);
492 #endif
493 
494 	return -ENOSYS;
495 }
496 
497 /* #define DEBUG_SPARC_BREAKPOINT */
498 
499 asmlinkage void sparc_breakpoint(struct pt_regs *regs)
500 {
501 	enum ctx_state prev_state = exception_enter();
502 	siginfo_t info;
503 
504 	if (test_thread_flag(TIF_32BIT)) {
505 		regs->tpc &= 0xffffffff;
506 		regs->tnpc &= 0xffffffff;
507 	}
508 #ifdef DEBUG_SPARC_BREAKPOINT
509         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
510 #endif
511 	info.si_signo = SIGTRAP;
512 	info.si_errno = 0;
513 	info.si_code = TRAP_BRKPT;
514 	info.si_addr = (void __user *)regs->tpc;
515 	info.si_trapno = 0;
516 	force_sig_info(SIGTRAP, &info, current);
517 #ifdef DEBUG_SPARC_BREAKPOINT
518 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
519 #endif
520 	exception_exit(prev_state);
521 }
522 
523 extern void check_pending(int signum);
524 
525 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
526 {
527         int nlen, err;
528 
529 	if (len < 0)
530 		return -EINVAL;
531 
532  	down_read(&uts_sem);
533 
534 	nlen = strlen(utsname()->domainname) + 1;
535 	err = -EINVAL;
536 	if (nlen > len)
537 		goto out;
538 
539 	err = -EFAULT;
540 	if (!copy_to_user(name, utsname()->domainname, nlen))
541 		err = 0;
542 
543 out:
544 	up_read(&uts_sem);
545 	return err;
546 }
547 
548 SYSCALL_DEFINE5(utrap_install, utrap_entry_t, type,
549 		utrap_handler_t, new_p, utrap_handler_t, new_d,
550 		utrap_handler_t __user *, old_p,
551 		utrap_handler_t __user *, old_d)
552 {
553 	if (type < UT_INSTRUCTION_EXCEPTION || type > UT_TRAP_INSTRUCTION_31)
554 		return -EINVAL;
555 	if (new_p == (utrap_handler_t)(long)UTH_NOCHANGE) {
556 		if (old_p) {
557 			if (!current_thread_info()->utraps) {
558 				if (put_user(NULL, old_p))
559 					return -EFAULT;
560 			} else {
561 				if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
562 					return -EFAULT;
563 			}
564 		}
565 		if (old_d) {
566 			if (put_user(NULL, old_d))
567 				return -EFAULT;
568 		}
569 		return 0;
570 	}
571 	if (!current_thread_info()->utraps) {
572 		current_thread_info()->utraps =
573 			kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL);
574 		if (!current_thread_info()->utraps)
575 			return -ENOMEM;
576 		current_thread_info()->utraps[0] = 1;
577 	} else {
578 		if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p &&
579 		    current_thread_info()->utraps[0] > 1) {
580 			unsigned long *p = current_thread_info()->utraps;
581 
582 			current_thread_info()->utraps =
583 				kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long),
584 					GFP_KERNEL);
585 			if (!current_thread_info()->utraps) {
586 				current_thread_info()->utraps = p;
587 				return -ENOMEM;
588 			}
589 			p[0]--;
590 			current_thread_info()->utraps[0] = 1;
591 			memcpy(current_thread_info()->utraps+1, p+1,
592 			       UT_TRAP_INSTRUCTION_31*sizeof(long));
593 		}
594 	}
595 	if (old_p) {
596 		if (put_user((utrap_handler_t)(current_thread_info()->utraps[type]), old_p))
597 			return -EFAULT;
598 	}
599 	if (old_d) {
600 		if (put_user(NULL, old_d))
601 			return -EFAULT;
602 	}
603 	current_thread_info()->utraps[type] = (long)new_p;
604 
605 	return 0;
606 }
607 
608 asmlinkage long sparc_memory_ordering(unsigned long model,
609 				      struct pt_regs *regs)
610 {
611 	if (model >= 3)
612 		return -EINVAL;
613 	regs->tstate = (regs->tstate & ~TSTATE_MM) | (model << 14);
614 	return 0;
615 }
616 
617 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
618 		struct sigaction __user *, oact, void __user *, restorer,
619 		size_t, sigsetsize)
620 {
621 	struct k_sigaction new_ka, old_ka;
622 	int ret;
623 
624 	/* XXX: Don't preclude handling different sized sigset_t's.  */
625 	if (sigsetsize != sizeof(sigset_t))
626 		return -EINVAL;
627 
628 	if (act) {
629 		new_ka.ka_restorer = restorer;
630 		if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
631 			return -EFAULT;
632 	}
633 
634 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
635 
636 	if (!ret && oact) {
637 		if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
638 			return -EFAULT;
639 	}
640 
641 	return ret;
642 }
643 
644 asmlinkage long sys_kern_features(void)
645 {
646 	return KERN_FEATURE_MIXED_MODE_STACK;
647 }
648