xref: /openbmc/linux/arch/parisc/kernel/sys_parisc.c (revision e2c75e76)
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 static unsigned long mmap_upper_limit(void)
74 {
75 	unsigned long stack_base;
76 
77 	/* Limit stack size - see setup_arg_pages() in fs/exec.c */
78 	stack_base = rlimit_max(RLIMIT_STACK);
79 	if (stack_base > STACK_SIZE_MAX)
80 		stack_base = STACK_SIZE_MAX;
81 
82 	/* Add space for stack randomization. */
83 	stack_base += (STACK_RND_MASK << PAGE_SHIFT);
84 
85 	return PAGE_ALIGN(STACK_TOP - stack_base);
86 }
87 
88 
89 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
90 		unsigned long len, unsigned long pgoff, unsigned long flags)
91 {
92 	struct mm_struct *mm = current->mm;
93 	struct vm_area_struct *vma, *prev;
94 	unsigned long task_size = TASK_SIZE;
95 	int do_color_align, last_mmap;
96 	struct vm_unmapped_area_info info;
97 
98 	if (len > task_size)
99 		return -ENOMEM;
100 
101 	do_color_align = 0;
102 	if (filp || (flags & MAP_SHARED))
103 		do_color_align = 1;
104 	last_mmap = GET_LAST_MMAP(filp);
105 
106 	if (flags & MAP_FIXED) {
107 		if ((flags & MAP_SHARED) && last_mmap &&
108 		    (addr - shared_align_offset(last_mmap, pgoff))
109 				& (SHM_COLOUR - 1))
110 			return -EINVAL;
111 		goto found_addr;
112 	}
113 
114 	if (addr) {
115 		if (do_color_align && last_mmap)
116 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
117 		else
118 			addr = PAGE_ALIGN(addr);
119 
120 		vma = find_vma_prev(mm, addr, &prev);
121 		if (task_size - len >= addr &&
122 		    (!vma || addr + len <= vm_start_gap(vma)) &&
123 		    (!prev || addr >= vm_end_gap(prev)))
124 			goto found_addr;
125 	}
126 
127 	info.flags = 0;
128 	info.length = len;
129 	info.low_limit = mm->mmap_legacy_base;
130 	info.high_limit = mmap_upper_limit();
131 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
132 	info.align_offset = shared_align_offset(last_mmap, pgoff);
133 	addr = vm_unmapped_area(&info);
134 
135 found_addr:
136 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
137 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
138 
139 	return addr;
140 }
141 
142 unsigned long
143 arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
144 			  const unsigned long len, const unsigned long pgoff,
145 			  const unsigned long flags)
146 {
147 	struct vm_area_struct *vma, *prev;
148 	struct mm_struct *mm = current->mm;
149 	unsigned long addr = addr0;
150 	int do_color_align, last_mmap;
151 	struct vm_unmapped_area_info info;
152 
153 #ifdef CONFIG_64BIT
154 	/* This should only ever run for 32-bit processes.  */
155 	BUG_ON(!test_thread_flag(TIF_32BIT));
156 #endif
157 
158 	/* requested length too big for entire address space */
159 	if (len > TASK_SIZE)
160 		return -ENOMEM;
161 
162 	do_color_align = 0;
163 	if (filp || (flags & MAP_SHARED))
164 		do_color_align = 1;
165 	last_mmap = GET_LAST_MMAP(filp);
166 
167 	if (flags & MAP_FIXED) {
168 		if ((flags & MAP_SHARED) && last_mmap &&
169 		    (addr - shared_align_offset(last_mmap, pgoff))
170 			& (SHM_COLOUR - 1))
171 			return -EINVAL;
172 		goto found_addr;
173 	}
174 
175 	/* requesting a specific address */
176 	if (addr) {
177 		if (do_color_align && last_mmap)
178 			addr = COLOR_ALIGN(addr, last_mmap, pgoff);
179 		else
180 			addr = PAGE_ALIGN(addr);
181 
182 		vma = find_vma_prev(mm, addr, &prev);
183 		if (TASK_SIZE - len >= addr &&
184 		    (!vma || addr + len <= vm_start_gap(vma)) &&
185 		    (!prev || addr >= vm_end_gap(prev)))
186 			goto found_addr;
187 	}
188 
189 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
190 	info.length = len;
191 	info.low_limit = PAGE_SIZE;
192 	info.high_limit = mm->mmap_base;
193 	info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
194 	info.align_offset = shared_align_offset(last_mmap, pgoff);
195 	addr = vm_unmapped_area(&info);
196 	if (!(addr & ~PAGE_MASK))
197 		goto found_addr;
198 	VM_BUG_ON(addr != -ENOMEM);
199 
200 	/*
201 	 * A failed mmap() very likely causes application failure,
202 	 * so fall back to the bottom-up function here. This scenario
203 	 * can happen with large stack limits and large mmap()
204 	 * allocations.
205 	 */
206 	return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
207 
208 found_addr:
209 	if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
210 		SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
211 
212 	return addr;
213 }
214 
215 static int mmap_is_legacy(void)
216 {
217 	if (current->personality & ADDR_COMPAT_LAYOUT)
218 		return 1;
219 
220 	/* parisc stack always grows up - so a unlimited stack should
221 	 * not be an indicator to use the legacy memory layout.
222 	 * if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
223 	 *	return 1;
224 	 */
225 
226 	return sysctl_legacy_va_layout;
227 }
228 
229 static unsigned long mmap_rnd(void)
230 {
231 	unsigned long rnd = 0;
232 
233 	if (current->flags & PF_RANDOMIZE)
234 		rnd = get_random_int() & MMAP_RND_MASK;
235 
236 	return rnd << PAGE_SHIFT;
237 }
238 
239 unsigned long arch_mmap_rnd(void)
240 {
241 	return (get_random_int() & MMAP_RND_MASK) << PAGE_SHIFT;
242 }
243 
244 static unsigned long mmap_legacy_base(void)
245 {
246 	return TASK_UNMAPPED_BASE + mmap_rnd();
247 }
248 
249 /*
250  * This function, called very early during the creation of a new
251  * process VM image, sets up which VM layout function to use:
252  */
253 void arch_pick_mmap_layout(struct mm_struct *mm)
254 {
255 	mm->mmap_legacy_base = mmap_legacy_base();
256 	mm->mmap_base = mmap_upper_limit();
257 
258 	if (mmap_is_legacy()) {
259 		mm->mmap_base = mm->mmap_legacy_base;
260 		mm->get_unmapped_area = arch_get_unmapped_area;
261 	} else {
262 		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
263 	}
264 }
265 
266 
267 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
268 	unsigned long prot, unsigned long flags, unsigned long fd,
269 	unsigned long pgoff)
270 {
271 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
272 	   we have. */
273 	return sys_mmap_pgoff(addr, len, prot, flags, fd,
274 			      pgoff >> (PAGE_SHIFT - 12));
275 }
276 
277 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
278 		unsigned long prot, unsigned long flags, unsigned long fd,
279 		unsigned long offset)
280 {
281 	if (!(offset & ~PAGE_MASK)) {
282 		return sys_mmap_pgoff(addr, len, prot, flags, fd,
283 					offset >> PAGE_SHIFT);
284 	} else {
285 		return -EINVAL;
286 	}
287 }
288 
289 /* Fucking broken ABI */
290 
291 #ifdef CONFIG_64BIT
292 asmlinkage long parisc_truncate64(const char __user * path,
293 					unsigned int high, unsigned int low)
294 {
295 	return sys_truncate(path, (long)high << 32 | low);
296 }
297 
298 asmlinkage long parisc_ftruncate64(unsigned int fd,
299 					unsigned int high, unsigned int low)
300 {
301 	return sys_ftruncate(fd, (long)high << 32 | low);
302 }
303 
304 /* stubs for the benefit of the syscall_table since truncate64 and truncate
305  * are identical on LP64 */
306 asmlinkage long sys_truncate64(const char __user * path, unsigned long length)
307 {
308 	return sys_truncate(path, length);
309 }
310 asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length)
311 {
312 	return sys_ftruncate(fd, length);
313 }
314 asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
315 {
316 	return sys_fcntl(fd, cmd, arg);
317 }
318 #else
319 
320 asmlinkage long parisc_truncate64(const char __user * path,
321 					unsigned int high, unsigned int low)
322 {
323 	return sys_truncate64(path, (loff_t)high << 32 | low);
324 }
325 
326 asmlinkage long parisc_ftruncate64(unsigned int fd,
327 					unsigned int high, unsigned int low)
328 {
329 	return sys_ftruncate64(fd, (loff_t)high << 32 | low);
330 }
331 #endif
332 
333 asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,
334 					unsigned int high, unsigned int low)
335 {
336 	return sys_pread64(fd, buf, count, (loff_t)high << 32 | low);
337 }
338 
339 asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,
340 			size_t count, unsigned int high, unsigned int low)
341 {
342 	return sys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);
343 }
344 
345 asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,
346 		                    size_t count)
347 {
348 	return sys_readahead(fd, (loff_t)high << 32 | low, count);
349 }
350 
351 asmlinkage long parisc_fadvise64_64(int fd,
352 			unsigned int high_off, unsigned int low_off,
353 			unsigned int high_len, unsigned int low_len, int advice)
354 {
355 	return sys_fadvise64_64(fd, (loff_t)high_off << 32 | low_off,
356 			(loff_t)high_len << 32 | low_len, advice);
357 }
358 
359 asmlinkage long parisc_sync_file_range(int fd,
360 			u32 hi_off, u32 lo_off, u32 hi_nbytes, u32 lo_nbytes,
361 			unsigned int flags)
362 {
363 	return sys_sync_file_range(fd, (loff_t)hi_off << 32 | lo_off,
364 			(loff_t)hi_nbytes << 32 | lo_nbytes, flags);
365 }
366 
367 asmlinkage long parisc_fallocate(int fd, int mode, u32 offhi, u32 offlo,
368 				u32 lenhi, u32 lenlo)
369 {
370         return sys_fallocate(fd, mode, ((u64)offhi << 32) | offlo,
371                              ((u64)lenhi << 32) | lenlo);
372 }
373 
374 long parisc_personality(unsigned long personality)
375 {
376 	long err;
377 
378 	if (personality(current->personality) == PER_LINUX32
379 	    && personality(personality) == PER_LINUX)
380 		personality = (personality & ~PER_MASK) | PER_LINUX32;
381 
382 	err = sys_personality(personality);
383 	if (personality(err) == PER_LINUX32)
384 		err = (err & ~PER_MASK) | PER_LINUX;
385 
386 	return err;
387 }
388