xref: /openbmc/linux/arch/parisc/kernel/sys_parisc.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 /*
4  *    PARISC specific syscalls
5  *
6  *    Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
7  *    Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
8  *    Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
9  *    Copyright (C) 1999-2020 Helge Deller <deller@gmx.de>
10  */
11 
12 #include <linux/uaccess.h>
13 #include <asm/elf.h>
14 #include <linux/file.h>
15 #include <linux/fs.h>
16 #include <linux/linkage.h>
17 #include <linux/mm.h>
18 #include <linux/mman.h>
19 #include <linux/sched/signal.h>
20 #include <linux/sched/mm.h>
21 #include <linux/shm.h>
22 #include <linux/syscalls.h>
23 #include <linux/utsname.h>
24 #include <linux/personality.h>
25 #include <linux/random.h>
26 #include <linux/compat.h>
27 
28 /* we construct an artificial offset for the mapping based on the physical
29  * address of the kernel mapping variable */
30 #define GET_LAST_MMAP(filp)		\
31 	(filp ? ((unsigned long) filp->f_mapping) >> 8 : 0UL)
32 #define SET_LAST_MMAP(filp, val)	\
33 	 { /* nothing */ }
34 
35 static int get_offset(unsigned int last_mmap)
36 {
37 	return (last_mmap & (SHM_COLOUR-1)) >> PAGE_SHIFT;
38 }
39 
40 static unsigned long shared_align_offset(unsigned int last_mmap,
41 					 unsigned long pgoff)
42 {
43 	return (get_offset(last_mmap) + pgoff) << PAGE_SHIFT;
44 }
45 
46 static inline unsigned long COLOR_ALIGN(unsigned long addr,
47 			 unsigned int last_mmap, unsigned long pgoff)
48 {
49 	unsigned long base = (addr+SHM_COLOUR-1) & ~(SHM_COLOUR-1);
50 	unsigned long off  = (SHM_COLOUR-1) &
51 		(shared_align_offset(last_mmap, pgoff) << PAGE_SHIFT);
52 
53 	return base + off;
54 }
55 
56 
57 #define STACK_SIZE_DEFAULT (USER_WIDE_MODE			\
58 			? (1 << 30)	/* 1 GB */		\
59 			: (CONFIG_STACK_MAX_DEFAULT_SIZE_MB*1024*1024))
60 
61 unsigned long calc_max_stack_size(unsigned long stack_max)
62 {
63 #ifdef CONFIG_COMPAT
64 	if (!USER_WIDE_MODE && (stack_max == COMPAT_RLIM_INFINITY))
65 		stack_max = STACK_SIZE_DEFAULT;
66 	else
67 #endif
68 	if (stack_max == RLIM_INFINITY)
69 		stack_max = STACK_SIZE_DEFAULT;
70 
71 	return stack_max;
72 }
73 
74 
75 /*
76  * Top of mmap area (just below the process stack).
77  */
78 
79 /*
80  * When called from arch_get_unmapped_area(), rlim_stack will be NULL,
81  * indicating that "current" should be used instead of a passed-in
82  * value from the exec bprm as done with arch_pick_mmap_layout().
83  */
84 static unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
85 {
86 	unsigned long stack_base;
87 
88 	/* Limit stack size - see setup_arg_pages() in fs/exec.c */
89 	stack_base = rlim_stack ? rlim_stack->rlim_max
90 				: rlimit_max(RLIMIT_STACK);
91 
92 	stack_base = calc_max_stack_size(stack_base);
93 
94 	/* Add space for stack randomization. */
95 	if (current->flags & PF_RANDOMIZE)
96 		stack_base += (STACK_RND_MASK << PAGE_SHIFT);
97 
98 	return PAGE_ALIGN(STACK_TOP - stack_base);
99 }
100 
101 
102 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
103 		unsigned long len, unsigned long pgoff, unsigned long flags)
104 {
105 	struct mm_struct *mm = current->mm;
106 	struct vm_area_struct *vma, *prev;
107 	unsigned long task_size = TASK_SIZE;
108 	int do_color_align, last_mmap;
109 	struct vm_unmapped_area_info info;
110 
111 	if (len > task_size)
112 		return -ENOMEM;
113 
114 	do_color_align = 0;
115 	if (filp || (flags & MAP_SHARED))
116 		do_color_align = 1;
117 	last_mmap = GET_LAST_MMAP(filp);
118 
119 	if (flags & MAP_FIXED) {
120 		if ((flags & MAP_SHARED) && last_mmap &&
121 		    (addr - shared_align_offset(last_mmap, pgoff))
122 				& (SHM_COLOUR - 1))
123 			return -EINVAL;
124 		goto found_addr;
125 	}
126 
127 	if (addr) {
128 		if (do_color_align && last_mmap)
129 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
130 		else
131 			addr = PAGE_ALIGN(addr);
132 
133 		vma = find_vma_prev(mm, addr, &prev);
134 		if (task_size - len >= addr &&
135 		    (!vma || addr + len <= vm_start_gap(vma)) &&
136 		    (!prev || addr >= vm_end_gap(prev)))
137 			goto found_addr;
138 	}
139 
140 	info.flags = 0;
141 	info.length = len;
142 	info.low_limit = mm->mmap_legacy_base;
143 	info.high_limit = mmap_upper_limit(NULL);
144 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
145 	info.align_offset = shared_align_offset(last_mmap, pgoff);
146 	addr = vm_unmapped_area(&info);
147 
148 found_addr:
149 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
150 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
151 
152 	return addr;
153 }
154 
155 unsigned long
156 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
157 			  const unsigned long len, const unsigned long pgoff,
158 			  const unsigned long flags)
159 {
160 	struct vm_area_struct *vma, *prev;
161 	struct mm_struct *mm = current->mm;
162 	unsigned long addr = addr0;
163 	int do_color_align, last_mmap;
164 	struct vm_unmapped_area_info info;
165 
166 	/* requested length too big for entire address space */
167 	if (len > TASK_SIZE)
168 		return -ENOMEM;
169 
170 	do_color_align = 0;
171 	if (filp || (flags & MAP_SHARED))
172 		do_color_align = 1;
173 	last_mmap = GET_LAST_MMAP(filp);
174 
175 	if (flags & MAP_FIXED) {
176 		if ((flags & MAP_SHARED) && last_mmap &&
177 		    (addr - shared_align_offset(last_mmap, pgoff))
178 			& (SHM_COLOUR - 1))
179 			return -EINVAL;
180 		goto found_addr;
181 	}
182 
183 	/* requesting a specific address */
184 	if (addr) {
185 		if (do_color_align && last_mmap)
186 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
187 		else
188 			addr = PAGE_ALIGN(addr);
189 
190 		vma = find_vma_prev(mm, addr, &prev);
191 		if (TASK_SIZE - len >= addr &&
192 		    (!vma || addr + len <= vm_start_gap(vma)) &&
193 		    (!prev || addr >= vm_end_gap(prev)))
194 			goto found_addr;
195 	}
196 
197 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
198 	info.length = len;
199 	info.low_limit = PAGE_SIZE;
200 	info.high_limit = mm->mmap_base;
201 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
202 	info.align_offset = shared_align_offset(last_mmap, pgoff);
203 	addr = vm_unmapped_area(&info);
204 	if (!(addr & ~PAGE_MASK))
205 		goto found_addr;
206 	VM_BUG_ON(addr != -ENOMEM);
207 
208 	/*
209 	 * A failed mmap() very likely causes application failure,
210 	 * so fall back to the bottom-up function here. This scenario
211 	 * can happen with large stack limits and large mmap()
212 	 * allocations.
213 	 */
214 	return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
215 
216 found_addr:
217 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
218 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
219 
220 	return addr;
221 }
222 
223 static int mmap_is_legacy(void)
224 {
225 	if (current->personality & ADDR_COMPAT_LAYOUT)
226 		return 1;
227 
228 	/* parisc stack always grows up - so a unlimited stack should
229 	 * not be an indicator to use the legacy memory layout.
230 	 * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
231 	 *	return 1;
232 	 */
233 
234 	return sysctl_legacy_va_layout;
235 }
236 
237 static unsigned long mmap_rnd(void)
238 {
239 	unsigned long rnd = 0;
240 
241 	if (current->flags & PF_RANDOMIZE)
242 		rnd = get_random_int() & MMAP_RND_MASK;
243 
244 	return rnd << PAGE_SHIFT;
245 }
246 
247 unsigned long arch_mmap_rnd(void)
248 {
249 	return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
250 }
251 
252 static unsigned long mmap_legacy_base(void)
253 {
254 	return TASK_UNMAPPED_BASE + mmap_rnd();
255 }
256 
257 /*
258  * This function, called very early during the creation of a new
259  * process VM image, sets up which VM layout function to use:
260  */
261 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
262 {
263 	mm->mmap_legacy_base = mmap_legacy_base();
264 	mm->mmap_base = mmap_upper_limit(rlim_stack);
265 
266 	if (mmap_is_legacy()) {
267 		mm->mmap_base = mm->mmap_legacy_base;
268 		mm->get_unmapped_area = arch_get_unmapped_area;
269 	} else {
270 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
271 	}
272 }
273 
274 
275 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
276 	unsigned long prot, unsigned long flags, unsigned long fd,
277 	unsigned long pgoff)
278 {
279 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
280 	   we have. */
281 	return ksys_mmap_pgoff(addr, len, prot, flags, fd,
282 			       pgoff >> (PAGE_SHIFT - 12));
283 }
284 
285 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
286 		unsigned long prot, unsigned long flags, unsigned long fd,
287 		unsigned long offset)
288 {
289 	if (!(offset & ~PAGE_MASK)) {
290 		return ksys_mmap_pgoff(addr, len, prot, flags, fd,
291 					offset >> PAGE_SHIFT);
292 	} else {
293 		return -EINVAL;
294 	}
295 }
296 
297 /* Fucking broken ABI */
298 
299 #ifdef CONFIG_64BIT
300 asmlinkage long parisc_truncate64(const char __user * path,
301 					unsigned int high, unsigned int low)
302 {
303 	return ksys_truncate(path, (long)high << 32 | low);
304 }
305 
306 asmlinkage long parisc_ftruncate64(unsigned int fd,
307 					unsigned int high, unsigned int low)
308 {
309 	return ksys_ftruncate(fd, (long)high << 32 | low);
310 }
311 
312 /* stubs for the benefit of the syscall_table since truncate64 and truncate
313  * are identical on LP64 */
314 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
315 {
316 	return ksys_truncate(path, length);
317 }
318 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
319 {
320 	return ksys_ftruncate(fd, length);
321 }
322 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
323 {
324 	return sys_fcntl(fd, cmd, arg);
325 }
326 #else
327 
328 asmlinkage long parisc_truncate64(const char __user * path,
329 					unsigned int high, unsigned int low)
330 {
331 	return ksys_truncate(path, (loff_t)high << 32 | low);
332 }
333 
334 asmlinkage long parisc_ftruncate64(unsigned int fd,
335 					unsigned int high, unsigned int low)
336 {
337 	return sys_ftruncate64(fd, (loff_t)high << 32 | low);
338 }
339 #endif
340 
341 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
342 					unsigned int high, unsigned int low)
343 {
344 	return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low);
345 }
346 
347 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
348 			size_t count, unsigned int high, unsigned int low)
349 {
350 	return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
351 }
352 
353 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
354 		                    size_t count)
355 {
356 	return ksys_readahead(fd, (loff_t)high << 32 | low, count);
357 }
358 
359 asmlinkage long parisc_fadvise64_64(int fd,
360 			unsigned int high_off, unsigned int low_off,
361 			unsigned int high_len, unsigned int low_len, int advice)
362 {
363 	return ksys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
364 			(loff_t)high_len << 32 | low_len, advice);
365 }
366 
367 asmlinkage long parisc_sync_file_range(int fd,
368 			u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
369 			unsigned int flags)
370 {
371 	return ksys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
372 			(loff_t)hi_nbytes << 32 | lo_nbytes, flags);
373 }
374 
375 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
376 				u32 lenhi, u32 lenlo)
377 {
378 	return ksys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
379 			      ((u64)lenhi << 32) | lenlo);
380 }
381 
382 long parisc_personality(unsigned long personality)
383 {
384 	long err;
385 
386 	if (personality(current->personality) == PER_LINUX32
387 	    && personality(personality) == PER_LINUX)
388 		personality = (personality & ~PER_MASK) | PER_LINUX32;
389 
390 	err = sys_personality(personality);
391 	if (personality(err) == PER_LINUX32)
392 		err = (err & ~PER_MASK) | PER_LINUX;
393 
394 	return err;
395 }
396 
397 /*
398  * Up to kernel v5.9 we defined O_NONBLOCK as 000200004,
399  * since then O_NONBLOCK is defined as 000200000.
400  *
401  * The following wrapper functions mask out the old
402  * O_NDELAY bit from calls which use O_NONBLOCK.
403  *
404  * XXX: Remove those in year 2022 (or later)?
405  */
406 
407 #define O_NONBLOCK_OLD		000200004
408 #define O_NONBLOCK_MASK_OUT	(O_NONBLOCK_OLD & ~O_NONBLOCK)
409 
410 static int FIX_O_NONBLOCK(int flags)
411 {
412 	if (flags & O_NONBLOCK_MASK_OUT) {
413 		struct task_struct *tsk = current;
414 		pr_warn_once("%s(%d) uses a deprecated O_NONBLOCK value.\n",
415 			tsk->comm, tsk->pid);
416 	}
417 	return flags & ~O_NONBLOCK_MASK_OUT;
418 }
419 
420 asmlinkage long parisc_timerfd_create(int clockid, int flags)
421 {
422 	flags = FIX_O_NONBLOCK(flags);
423 	return sys_timerfd_create(clockid, flags);
424 }
425 
426 asmlinkage long parisc_signalfd4(int ufd, sigset_t __user *user_mask,
427 	size_t sizemask, int flags)
428 {
429 	flags = FIX_O_NONBLOCK(flags);
430 	return sys_signalfd4(ufd, user_mask, sizemask, flags);
431 }
432 
433 #ifdef CONFIG_COMPAT
434 asmlinkage long parisc_compat_signalfd4(int ufd,
435 	compat_sigset_t __user *user_mask,
436 	compat_size_t sizemask, int flags)
437 {
438 	flags = FIX_O_NONBLOCK(flags);
439 	return compat_sys_signalfd4(ufd, user_mask, sizemask, flags);
440 }
441 #endif
442 
443 asmlinkage long parisc_eventfd2(unsigned int count, int flags)
444 {
445 	flags = FIX_O_NONBLOCK(flags);
446 	return sys_eventfd2(count, flags);
447 }
448 
449 asmlinkage long parisc_userfaultfd(int flags)
450 {
451 	flags = FIX_O_NONBLOCK(flags);
452 	return sys_userfaultfd(flags);
453 }
454 
455 asmlinkage long parisc_pipe2(int __user *fildes, int flags)
456 {
457 	flags = FIX_O_NONBLOCK(flags);
458 	return sys_pipe2(fildes, flags);
459 }
460 
461 asmlinkage long parisc_inotify_init1(int flags)
462 {
463 	flags = FIX_O_NONBLOCK(flags);
464 	return sys_inotify_init1(flags);
465 }
466