xref: /openbmc/linux/arch/parisc/kernel/sys_parisc.c (revision 11a163f2)
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  * Top of mmap area (just below the process stack).
58  */
59 
60 /*
61  * When called from arch_get_unmapped_area(), rlim_stack will be NULL,
62  * indicating that "current" should be used instead of a passed-in
63  * value from the exec bprm as done with arch_pick_mmap_layout().
64  */
65 static unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
66 {
67 	unsigned long stack_base;
68 
69 	/* Limit stack size - see setup_arg_pages() in fs/exec.c */
70 	stack_base = rlim_stack ? rlim_stack->rlim_max
71 				: rlimit_max(RLIMIT_STACK);
72 	if (stack_base > STACK_SIZE_MAX)
73 		stack_base = STACK_SIZE_MAX;
74 
75 	/* Add space for stack randomization. */
76 	if (current->flags & PF_RANDOMIZE)
77 		stack_base += (STACK_RND_MASK << PAGE_SHIFT);
78 
79 	return PAGE_ALIGN(STACK_TOP - stack_base);
80 }
81 
82 
83 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
84 		unsigned long len, unsigned long pgoff, unsigned long flags)
85 {
86 	struct mm_struct *mm = current->mm;
87 	struct vm_area_struct *vma, *prev;
88 	unsigned long task_size = TASK_SIZE;
89 	int do_color_align, last_mmap;
90 	struct vm_unmapped_area_info info;
91 
92 	if (len > task_size)
93 		return -ENOMEM;
94 
95 	do_color_align = 0;
96 	if (filp || (flags & MAP_SHARED))
97 		do_color_align = 1;
98 	last_mmap = GET_LAST_MMAP(filp);
99 
100 	if (flags & MAP_FIXED) {
101 		if ((flags & MAP_SHARED) && last_mmap &&
102 		    (addr - shared_align_offset(last_mmap, pgoff))
103 				& (SHM_COLOUR - 1))
104 			return -EINVAL;
105 		goto found_addr;
106 	}
107 
108 	if (addr) {
109 		if (do_color_align && last_mmap)
110 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
111 		else
112 			addr = PAGE_ALIGN(addr);
113 
114 		vma = find_vma_prev(mm, addr, &prev);
115 		if (task_size - len >= addr &&
116 		    (!vma || addr + len <= vm_start_gap(vma)) &&
117 		    (!prev || addr >= vm_end_gap(prev)))
118 			goto found_addr;
119 	}
120 
121 	info.flags = 0;
122 	info.length = len;
123 	info.low_limit = mm->mmap_legacy_base;
124 	info.high_limit = mmap_upper_limit(NULL);
125 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
126 	info.align_offset = shared_align_offset(last_mmap, pgoff);
127 	addr = vm_unmapped_area(&info);
128 
129 found_addr:
130 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
131 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
132 
133 	return addr;
134 }
135 
136 unsigned long
137 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
138 			  const unsigned long len, const unsigned long pgoff,
139 			  const unsigned long flags)
140 {
141 	struct vm_area_struct *vma, *prev;
142 	struct mm_struct *mm = current->mm;
143 	unsigned long addr = addr0;
144 	int do_color_align, last_mmap;
145 	struct vm_unmapped_area_info info;
146 
147 	/* requested length too big for entire address space */
148 	if (len > TASK_SIZE)
149 		return -ENOMEM;
150 
151 	do_color_align = 0;
152 	if (filp || (flags & MAP_SHARED))
153 		do_color_align = 1;
154 	last_mmap = GET_LAST_MMAP(filp);
155 
156 	if (flags & MAP_FIXED) {
157 		if ((flags & MAP_SHARED) && last_mmap &&
158 		    (addr - shared_align_offset(last_mmap, pgoff))
159 			& (SHM_COLOUR - 1))
160 			return -EINVAL;
161 		goto found_addr;
162 	}
163 
164 	/* requesting a specific address */
165 	if (addr) {
166 		if (do_color_align && last_mmap)
167 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
168 		else
169 			addr = PAGE_ALIGN(addr);
170 
171 		vma = find_vma_prev(mm, addr, &prev);
172 		if (TASK_SIZE - len >= addr &&
173 		    (!vma || addr + len <= vm_start_gap(vma)) &&
174 		    (!prev || addr >= vm_end_gap(prev)))
175 			goto found_addr;
176 	}
177 
178 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
179 	info.length = len;
180 	info.low_limit = PAGE_SIZE;
181 	info.high_limit = mm->mmap_base;
182 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
183 	info.align_offset = shared_align_offset(last_mmap, pgoff);
184 	addr = vm_unmapped_area(&info);
185 	if (!(addr & ~PAGE_MASK))
186 		goto found_addr;
187 	VM_BUG_ON(addr != -ENOMEM);
188 
189 	/*
190 	 * A failed mmap() very likely causes application failure,
191 	 * so fall back to the bottom-up function here. This scenario
192 	 * can happen with large stack limits and large mmap()
193 	 * allocations.
194 	 */
195 	return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
196 
197 found_addr:
198 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
199 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
200 
201 	return addr;
202 }
203 
204 static int mmap_is_legacy(void)
205 {
206 	if (current->personality & ADDR_COMPAT_LAYOUT)
207 		return 1;
208 
209 	/* parisc stack always grows up - so a unlimited stack should
210 	 * not be an indicator to use the legacy memory layout.
211 	 * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
212 	 *	return 1;
213 	 */
214 
215 	return sysctl_legacy_va_layout;
216 }
217 
218 static unsigned long mmap_rnd(void)
219 {
220 	unsigned long rnd = 0;
221 
222 	if (current->flags & PF_RANDOMIZE)
223 		rnd = get_random_int() & MMAP_RND_MASK;
224 
225 	return rnd << PAGE_SHIFT;
226 }
227 
228 unsigned long arch_mmap_rnd(void)
229 {
230 	return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
231 }
232 
233 static unsigned long mmap_legacy_base(void)
234 {
235 	return TASK_UNMAPPED_BASE + mmap_rnd();
236 }
237 
238 /*
239  * This function, called very early during the creation of a new
240  * process VM image, sets up which VM layout function to use:
241  */
242 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
243 {
244 	mm->mmap_legacy_base = mmap_legacy_base();
245 	mm->mmap_base = mmap_upper_limit(rlim_stack);
246 
247 	if (mmap_is_legacy()) {
248 		mm->mmap_base = mm->mmap_legacy_base;
249 		mm->get_unmapped_area = arch_get_unmapped_area;
250 	} else {
251 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
252 	}
253 }
254 
255 
256 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
257 	unsigned long prot, unsigned long flags, unsigned long fd,
258 	unsigned long pgoff)
259 {
260 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
261 	   we have. */
262 	return ksys_mmap_pgoff(addr, len, prot, flags, fd,
263 			       pgoff >> (PAGE_SHIFT - 12));
264 }
265 
266 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
267 		unsigned long prot, unsigned long flags, unsigned long fd,
268 		unsigned long offset)
269 {
270 	if (!(offset & ~PAGE_MASK)) {
271 		return ksys_mmap_pgoff(addr, len, prot, flags, fd,
272 					offset >> PAGE_SHIFT);
273 	} else {
274 		return -EINVAL;
275 	}
276 }
277 
278 /* Fucking broken ABI */
279 
280 #ifdef CONFIG_64BIT
281 asmlinkage long parisc_truncate64(const char __user * path,
282 					unsigned int high, unsigned int low)
283 {
284 	return ksys_truncate(path, (long)high << 32 | low);
285 }
286 
287 asmlinkage long parisc_ftruncate64(unsigned int fd,
288 					unsigned int high, unsigned int low)
289 {
290 	return ksys_ftruncate(fd, (long)high << 32 | low);
291 }
292 
293 /* stubs for the benefit of the syscall_table since truncate64 and truncate
294  * are identical on LP64 */
295 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
296 {
297 	return ksys_truncate(path, length);
298 }
299 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
300 {
301 	return ksys_ftruncate(fd, length);
302 }
303 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
304 {
305 	return sys_fcntl(fd, cmd, arg);
306 }
307 #else
308 
309 asmlinkage long parisc_truncate64(const char __user * path,
310 					unsigned int high, unsigned int low)
311 {
312 	return ksys_truncate(path, (loff_t)high << 32 | low);
313 }
314 
315 asmlinkage long parisc_ftruncate64(unsigned int fd,
316 					unsigned int high, unsigned int low)
317 {
318 	return sys_ftruncate64(fd, (loff_t)high << 32 | low);
319 }
320 #endif
321 
322 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
323 					unsigned int high, unsigned int low)
324 {
325 	return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low);
326 }
327 
328 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
329 			size_t count, unsigned int high, unsigned int low)
330 {
331 	return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
332 }
333 
334 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
335 		                    size_t count)
336 {
337 	return ksys_readahead(fd, (loff_t)high << 32 | low, count);
338 }
339 
340 asmlinkage long parisc_fadvise64_64(int fd,
341 			unsigned int high_off, unsigned int low_off,
342 			unsigned int high_len, unsigned int low_len, int advice)
343 {
344 	return ksys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
345 			(loff_t)high_len << 32 | low_len, advice);
346 }
347 
348 asmlinkage long parisc_sync_file_range(int fd,
349 			u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
350 			unsigned int flags)
351 {
352 	return ksys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
353 			(loff_t)hi_nbytes << 32 | lo_nbytes, flags);
354 }
355 
356 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
357 				u32 lenhi, u32 lenlo)
358 {
359 	return ksys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
360 			      ((u64)lenhi << 32) | lenlo);
361 }
362 
363 long parisc_personality(unsigned long personality)
364 {
365 	long err;
366 
367 	if (personality(current->personality) == PER_LINUX32
368 	    && personality(personality) == PER_LINUX)
369 		personality = (personality & ~PER_MASK) | PER_LINUX32;
370 
371 	err = sys_personality(personality);
372 	if (personality(err) == PER_LINUX32)
373 		err = (err & ~PER_MASK) | PER_LINUX;
374 
375 	return err;
376 }
377 
378 /*
379  * Up to kernel v5.9 we defined O_NONBLOCK as 000200004,
380  * since then O_NONBLOCK is defined as 000200000.
381  *
382  * The following wrapper functions mask out the old
383  * O_NDELAY bit from calls which use O_NONBLOCK.
384  *
385  * XXX: Remove those in year 2022 (or later)?
386  */
387 
388 #define O_NONBLOCK_OLD		000200004
389 #define O_NONBLOCK_MASK_OUT	(O_NONBLOCK_OLD & ~O_NONBLOCK)
390 
391 static int FIX_O_NONBLOCK(int flags)
392 {
393 	if (flags & O_NONBLOCK_MASK_OUT) {
394 		struct task_struct *tsk = current;
395 		pr_warn_once("%s(%d) uses a deprecated O_NONBLOCK value.\n",
396 			tsk->comm, tsk->pid);
397 	}
398 	return flags & ~O_NONBLOCK_MASK_OUT;
399 }
400 
401 asmlinkage long parisc_timerfd_create(int clockid, int flags)
402 {
403 	flags = FIX_O_NONBLOCK(flags);
404 	return sys_timerfd_create(clockid, flags);
405 }
406 
407 asmlinkage long parisc_signalfd4(int ufd, sigset_t __user *user_mask,
408 	size_t sizemask, int flags)
409 {
410 	flags = FIX_O_NONBLOCK(flags);
411 	return sys_signalfd4(ufd, user_mask, sizemask, flags);
412 }
413 
414 #ifdef CONFIG_COMPAT
415 asmlinkage long parisc_compat_signalfd4(int ufd,
416 	compat_sigset_t __user *user_mask,
417 	compat_size_t sizemask, int flags)
418 {
419 	flags = FIX_O_NONBLOCK(flags);
420 	return compat_sys_signalfd4(ufd, user_mask, sizemask, flags);
421 }
422 #endif
423 
424 asmlinkage long parisc_eventfd2(unsigned int count, int flags)
425 {
426 	flags = FIX_O_NONBLOCK(flags);
427 	return sys_eventfd2(count, flags);
428 }
429 
430 asmlinkage long parisc_userfaultfd(int flags)
431 {
432 	flags = FIX_O_NONBLOCK(flags);
433 	return sys_userfaultfd(flags);
434 }
435 
436 asmlinkage long parisc_pipe2(int __user *fildes, int flags)
437 {
438 	flags = FIX_O_NONBLOCK(flags);
439 	return sys_pipe2(fildes, flags);
440 }
441 
442 asmlinkage long parisc_inotify_init1(int flags)
443 {
444 	flags = FIX_O_NONBLOCK(flags);
445 	return sys_inotify_init1(flags);
446 }
447