xref: /openbmc/linux/arch/parisc/kernel/sys_parisc.c (revision f519f0be)
1 
2 /*
3  *    PARISC specific syscalls
4  *
5  *    Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
6  *    Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
7  *    Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
8  *    Copyright (C) 1999-2014 Helge Deller <deller@gmx.de>
9  *
10  *
11  *    This program is free software; you can redistribute it and/or modify
12  *    it under the terms of the GNU General Public License as published by
13  *    the Free Software Foundation; either version 2 of the License, or
14  *    (at your option) any later version.
15  *
16  *    This program is distributed in the hope that it will be useful,
17  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
18  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  *    GNU General Public License for more details.
20  *
21  *    You should have received a copy of the GNU General Public License
22  *    along with this program; if not, write to the Free Software
23  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
24  */
25 
26 #include <linux/uaccess.h>
27 #include <asm/elf.h>
28 #include <linux/file.h>
29 #include <linux/fs.h>
30 #include <linux/linkage.h>
31 #include <linux/mm.h>
32 #include <linux/mman.h>
33 #include <linux/sched/signal.h>
34 #include <linux/sched/mm.h>
35 #include <linux/shm.h>
36 #include <linux/syscalls.h>
37 #include <linux/utsname.h>
38 #include <linux/personality.h>
39 #include <linux/random.h>
40 
41 /* we construct an artificial offset for the mapping based on the physical
42  * address of the kernel mapping variable */
43 #define GET_LAST_MMAP(filp)		\
44 	(filp ? ((unsigned long) filp->f_mapping) >> 8 : 0UL)
45 #define SET_LAST_MMAP(filp, val)	\
46 	 { /* nothing */ }
47 
48 static int get_offset(unsigned int last_mmap)
49 {
50 	return (last_mmap & (SHM_COLOUR-1)) >> PAGE_SHIFT;
51 }
52 
53 static unsigned long shared_align_offset(unsigned int last_mmap,
54 					 unsigned long pgoff)
55 {
56 	return (get_offset(last_mmap) + pgoff) << PAGE_SHIFT;
57 }
58 
59 static inline unsigned long COLOR_ALIGN(unsigned long addr,
60 			 unsigned int last_mmap, unsigned long pgoff)
61 {
62 	unsigned long base = (addr+SHM_COLOUR-1) & ~(SHM_COLOUR-1);
63 	unsigned long off  = (SHM_COLOUR-1) &
64 		(shared_align_offset(last_mmap, pgoff) << PAGE_SHIFT);
65 
66 	return base + off;
67 }
68 
69 /*
70  * Top of mmap area (just below the process stack).
71  */
72 
73 /*
74  * When called from arch_get_unmapped_area(), rlim_stack will be NULL,
75  * indicating that "current" should be used instead of a passed-in
76  * value from the exec bprm as done with arch_pick_mmap_layout().
77  */
78 static unsigned long mmap_upper_limit(struct rlimit *rlim_stack)
79 {
80 	unsigned long stack_base;
81 
82 	/* Limit stack size - see setup_arg_pages() in fs/exec.c */
83 	stack_base = rlim_stack ? rlim_stack->rlim_max
84 				: rlimit_max(RLIMIT_STACK);
85 	if (stack_base > STACK_SIZE_MAX)
86 		stack_base = STACK_SIZE_MAX;
87 
88 	/* Add space for stack randomization. */
89 	if (current->flags & PF_RANDOMIZE)
90 		stack_base += (STACK_RND_MASK << PAGE_SHIFT);
91 
92 	return PAGE_ALIGN(STACK_TOP - stack_base);
93 }
94 
95 
96 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
97 		unsigned long len, unsigned long pgoff, unsigned long flags)
98 {
99 	struct mm_struct *mm = current->mm;
100 	struct vm_area_struct *vma, *prev;
101 	unsigned long task_size = TASK_SIZE;
102 	int do_color_align, last_mmap;
103 	struct vm_unmapped_area_info info;
104 
105 	if (len > task_size)
106 		return -ENOMEM;
107 
108 	do_color_align = 0;
109 	if (filp || (flags & MAP_SHARED))
110 		do_color_align = 1;
111 	last_mmap = GET_LAST_MMAP(filp);
112 
113 	if (flags & MAP_FIXED) {
114 		if ((flags & MAP_SHARED) && last_mmap &&
115 		    (addr - shared_align_offset(last_mmap, pgoff))
116 				& (SHM_COLOUR - 1))
117 			return -EINVAL;
118 		goto found_addr;
119 	}
120 
121 	if (addr) {
122 		if (do_color_align && last_mmap)
123 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
124 		else
125 			addr = PAGE_ALIGN(addr);
126 
127 		vma = find_vma_prev(mm, addr, &prev);
128 		if (task_size - len >= addr &&
129 		    (!vma || addr + len <= vm_start_gap(vma)) &&
130 		    (!prev || addr >= vm_end_gap(prev)))
131 			goto found_addr;
132 	}
133 
134 	info.flags = 0;
135 	info.length = len;
136 	info.low_limit = mm->mmap_legacy_base;
137 	info.high_limit = mmap_upper_limit(NULL);
138 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
139 	info.align_offset = shared_align_offset(last_mmap, pgoff);
140 	addr = vm_unmapped_area(&info);
141 
142 found_addr:
143 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
144 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
145 
146 	return addr;
147 }
148 
149 unsigned long
150 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
151 			  const unsigned long len, const unsigned long pgoff,
152 			  const unsigned long flags)
153 {
154 	struct vm_area_struct *vma, *prev;
155 	struct mm_struct *mm = current->mm;
156 	unsigned long addr = addr0;
157 	int do_color_align, last_mmap;
158 	struct vm_unmapped_area_info info;
159 
160 	/* requested length too big for entire address space */
161 	if (len > TASK_SIZE)
162 		return -ENOMEM;
163 
164 	do_color_align = 0;
165 	if (filp || (flags & MAP_SHARED))
166 		do_color_align = 1;
167 	last_mmap = GET_LAST_MMAP(filp);
168 
169 	if (flags & MAP_FIXED) {
170 		if ((flags & MAP_SHARED) && last_mmap &&
171 		    (addr - shared_align_offset(last_mmap, pgoff))
172 			& (SHM_COLOUR - 1))
173 			return -EINVAL;
174 		goto found_addr;
175 	}
176 
177 	/* requesting a specific address */
178 	if (addr) {
179 		if (do_color_align && last_mmap)
180 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
181 		else
182 			addr = PAGE_ALIGN(addr);
183 
184 		vma = find_vma_prev(mm, addr, &prev);
185 		if (TASK_SIZE - len >= addr &&
186 		    (!vma || addr + len <= vm_start_gap(vma)) &&
187 		    (!prev || addr >= vm_end_gap(prev)))
188 			goto found_addr;
189 	}
190 
191 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
192 	info.length = len;
193 	info.low_limit = PAGE_SIZE;
194 	info.high_limit = mm->mmap_base;
195 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
196 	info.align_offset = shared_align_offset(last_mmap, pgoff);
197 	addr = vm_unmapped_area(&info);
198 	if (!(addr & ~PAGE_MASK))
199 		goto found_addr;
200 	VM_BUG_ON(addr != -ENOMEM);
201 
202 	/*
203 	 * A failed mmap() very likely causes application failure,
204 	 * so fall back to the bottom-up function here. This scenario
205 	 * can happen with large stack limits and large mmap()
206 	 * allocations.
207 	 */
208 	return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
209 
210 found_addr:
211 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
212 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
213 
214 	return addr;
215 }
216 
217 static int mmap_is_legacy(void)
218 {
219 	if (current->personality & ADDR_COMPAT_LAYOUT)
220 		return 1;
221 
222 	/* parisc stack always grows up - so a unlimited stack should
223 	 * not be an indicator to use the legacy memory layout.
224 	 * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
225 	 *	return 1;
226 	 */
227 
228 	return sysctl_legacy_va_layout;
229 }
230 
231 static unsigned long mmap_rnd(void)
232 {
233 	unsigned long rnd = 0;
234 
235 	if (current->flags & PF_RANDOMIZE)
236 		rnd = get_random_int() & MMAP_RND_MASK;
237 
238 	return rnd << PAGE_SHIFT;
239 }
240 
241 unsigned long arch_mmap_rnd(void)
242 {
243 	return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
244 }
245 
246 static unsigned long mmap_legacy_base(void)
247 {
248 	return TASK_UNMAPPED_BASE + mmap_rnd();
249 }
250 
251 /*
252  * This function, called very early during the creation of a new
253  * process VM image, sets up which VM layout function to use:
254  */
255 void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
256 {
257 	mm->mmap_legacy_base = mmap_legacy_base();
258 	mm->mmap_base = mmap_upper_limit(rlim_stack);
259 
260 	if (mmap_is_legacy()) {
261 		mm->mmap_base = mm->mmap_legacy_base;
262 		mm->get_unmapped_area = arch_get_unmapped_area;
263 	} else {
264 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
265 	}
266 }
267 
268 
269 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
270 	unsigned long prot, unsigned long flags, unsigned long fd,
271 	unsigned long pgoff)
272 {
273 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
274 	   we have. */
275 	return ksys_mmap_pgoff(addr, len, prot, flags, fd,
276 			       pgoff >> (PAGE_SHIFT - 12));
277 }
278 
279 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
280 		unsigned long prot, unsigned long flags, unsigned long fd,
281 		unsigned long offset)
282 {
283 	if (!(offset & ~PAGE_MASK)) {
284 		return ksys_mmap_pgoff(addr, len, prot, flags, fd,
285 					offset >> PAGE_SHIFT);
286 	} else {
287 		return -EINVAL;
288 	}
289 }
290 
291 /* Fucking broken ABI */
292 
293 #ifdef CONFIG_64BIT
294 asmlinkage long parisc_truncate64(const char __user * path,
295 					unsigned int high, unsigned int low)
296 {
297 	return ksys_truncate(path, (long)high << 32 | low);
298 }
299 
300 asmlinkage long parisc_ftruncate64(unsigned int fd,
301 					unsigned int high, unsigned int low)
302 {
303 	return ksys_ftruncate(fd, (long)high << 32 | low);
304 }
305 
306 /* stubs for the benefit of the syscall_table since truncate64 and truncate
307  * are identical on LP64 */
308 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
309 {
310 	return ksys_truncate(path, length);
311 }
312 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
313 {
314 	return ksys_ftruncate(fd, length);
315 }
316 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
317 {
318 	return sys_fcntl(fd, cmd, arg);
319 }
320 #else
321 
322 asmlinkage long parisc_truncate64(const char __user * path,
323 					unsigned int high, unsigned int low)
324 {
325 	return ksys_truncate(path, (loff_t)high << 32 | low);
326 }
327 
328 asmlinkage long parisc_ftruncate64(unsigned int fd,
329 					unsigned int high, unsigned int low)
330 {
331 	return sys_ftruncate64(fd, (loff_t)high << 32 | low);
332 }
333 #endif
334 
335 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
336 					unsigned int high, unsigned int low)
337 {
338 	return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low);
339 }
340 
341 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
342 			size_t count, unsigned int high, unsigned int low)
343 {
344 	return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
345 }
346 
347 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
348 		                    size_t count)
349 {
350 	return ksys_readahead(fd, (loff_t)high << 32 | low, count);
351 }
352 
353 asmlinkage long parisc_fadvise64_64(int fd,
354 			unsigned int high_off, unsigned int low_off,
355 			unsigned int high_len, unsigned int low_len, int advice)
356 {
357 	return ksys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
358 			(loff_t)high_len << 32 | low_len, advice);
359 }
360 
361 asmlinkage long parisc_sync_file_range(int fd,
362 			u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
363 			unsigned int flags)
364 {
365 	return ksys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
366 			(loff_t)hi_nbytes << 32 | lo_nbytes, flags);
367 }
368 
369 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
370 				u32 lenhi, u32 lenlo)
371 {
372 	return ksys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
373 			      ((u64)lenhi << 32) | lenlo);
374 }
375 
376 long parisc_personality(unsigned long personality)
377 {
378 	long err;
379 
380 	if (personality(current->personality) == PER_LINUX32
381 	    && personality(personality) == PER_LINUX)
382 		personality = (personality & ~PER_MASK) | PER_LINUX32;
383 
384 	err = sys_personality(personality);
385 	if (personality(err) == PER_LINUX32)
386 		err = (err & ~PER_MASK) | PER_LINUX;
387 
388 	return err;
389 }
390