xref: /openbmc/linux/arch/s390/kernel/compat_linux.c (revision d0b73b48)
1 /*
2  *  S390 version
3  *    Copyright IBM Corp. 2000
4  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
5  *               Gerhard Tonn (ton@de.ibm.com)
6  *               Thomas Spatzier (tspat@de.ibm.com)
7  *
8  *  Conversion between 31bit and 64bit native syscalls.
9  *
10  * Heavily inspired by the 32-bit Sparc compat code which is
11  * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
12  * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
13  *
14  */
15 
16 
17 #include <linux/kernel.h>
18 #include <linux/sched.h>
19 #include <linux/fs.h>
20 #include <linux/mm.h>
21 #include <linux/file.h>
22 #include <linux/signal.h>
23 #include <linux/resource.h>
24 #include <linux/times.h>
25 #include <linux/smp.h>
26 #include <linux/sem.h>
27 #include <linux/msg.h>
28 #include <linux/shm.h>
29 #include <linux/uio.h>
30 #include <linux/quota.h>
31 #include <linux/module.h>
32 #include <linux/poll.h>
33 #include <linux/personality.h>
34 #include <linux/stat.h>
35 #include <linux/filter.h>
36 #include <linux/highmem.h>
37 #include <linux/highuid.h>
38 #include <linux/mman.h>
39 #include <linux/ipv6.h>
40 #include <linux/in.h>
41 #include <linux/icmpv6.h>
42 #include <linux/syscalls.h>
43 #include <linux/sysctl.h>
44 #include <linux/binfmts.h>
45 #include <linux/capability.h>
46 #include <linux/compat.h>
47 #include <linux/vfs.h>
48 #include <linux/ptrace.h>
49 #include <linux/fadvise.h>
50 #include <linux/ipc.h>
51 #include <linux/slab.h>
52 
53 #include <asm/types.h>
54 #include <asm/uaccess.h>
55 
56 #include <net/scm.h>
57 #include <net/sock.h>
58 
59 #include "compat_linux.h"
60 
61 u32 psw32_user_bits = PSW32_MASK_DAT | PSW32_MASK_IO | PSW32_MASK_EXT |
62 		      PSW32_DEFAULT_KEY | PSW32_MASK_BASE | PSW32_MASK_MCHECK |
63 		      PSW32_MASK_PSTATE | PSW32_ASC_HOME;
64 
65 /* For this source file, we want overflow handling. */
66 
67 #undef high2lowuid
68 #undef high2lowgid
69 #undef low2highuid
70 #undef low2highgid
71 #undef SET_UID16
72 #undef SET_GID16
73 #undef NEW_TO_OLD_UID
74 #undef NEW_TO_OLD_GID
75 #undef SET_OLDSTAT_UID
76 #undef SET_OLDSTAT_GID
77 #undef SET_STAT_UID
78 #undef SET_STAT_GID
79 
80 #define high2lowuid(uid) ((uid) > 65535) ? (u16)overflowuid : (u16)(uid)
81 #define high2lowgid(gid) ((gid) > 65535) ? (u16)overflowgid : (u16)(gid)
82 #define low2highuid(uid) ((uid) == (u16)-1) ? (uid_t)-1 : (uid_t)(uid)
83 #define low2highgid(gid) ((gid) == (u16)-1) ? (gid_t)-1 : (gid_t)(gid)
84 #define SET_UID16(var, uid)	var = high2lowuid(uid)
85 #define SET_GID16(var, gid)	var = high2lowgid(gid)
86 #define NEW_TO_OLD_UID(uid)	high2lowuid(uid)
87 #define NEW_TO_OLD_GID(gid)	high2lowgid(gid)
88 #define SET_OLDSTAT_UID(stat, uid)	(stat).st_uid = high2lowuid(uid)
89 #define SET_OLDSTAT_GID(stat, gid)	(stat).st_gid = high2lowgid(gid)
90 #define SET_STAT_UID(stat, uid)		(stat).st_uid = high2lowuid(uid)
91 #define SET_STAT_GID(stat, gid)		(stat).st_gid = high2lowgid(gid)
92 
93 asmlinkage long sys32_chown16(const char __user * filename, u16 user, u16 group)
94 {
95 	return sys_chown(filename, low2highuid(user), low2highgid(group));
96 }
97 
98 asmlinkage long sys32_lchown16(const char __user * filename, u16 user, u16 group)
99 {
100 	return sys_lchown(filename, low2highuid(user), low2highgid(group));
101 }
102 
103 asmlinkage long sys32_fchown16(unsigned int fd, u16 user, u16 group)
104 {
105 	return sys_fchown(fd, low2highuid(user), low2highgid(group));
106 }
107 
108 asmlinkage long sys32_setregid16(u16 rgid, u16 egid)
109 {
110 	return sys_setregid(low2highgid(rgid), low2highgid(egid));
111 }
112 
113 asmlinkage long sys32_setgid16(u16 gid)
114 {
115 	return sys_setgid((gid_t)gid);
116 }
117 
118 asmlinkage long sys32_setreuid16(u16 ruid, u16 euid)
119 {
120 	return sys_setreuid(low2highuid(ruid), low2highuid(euid));
121 }
122 
123 asmlinkage long sys32_setuid16(u16 uid)
124 {
125 	return sys_setuid((uid_t)uid);
126 }
127 
128 asmlinkage long sys32_setresuid16(u16 ruid, u16 euid, u16 suid)
129 {
130 	return sys_setresuid(low2highuid(ruid), low2highuid(euid),
131 		low2highuid(suid));
132 }
133 
134 asmlinkage long sys32_getresuid16(u16 __user *ruidp, u16 __user *euidp, u16 __user *suidp)
135 {
136 	const struct cred *cred = current_cred();
137 	int retval;
138 	u16 ruid, euid, suid;
139 
140 	ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
141 	euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
142 	suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
143 
144 	if (!(retval   = put_user(ruid, ruidp)) &&
145 	    !(retval   = put_user(euid, euidp)))
146 		retval = put_user(suid, suidp);
147 
148 	return retval;
149 }
150 
151 asmlinkage long sys32_setresgid16(u16 rgid, u16 egid, u16 sgid)
152 {
153 	return sys_setresgid(low2highgid(rgid), low2highgid(egid),
154 		low2highgid(sgid));
155 }
156 
157 asmlinkage long sys32_getresgid16(u16 __user *rgidp, u16 __user *egidp, u16 __user *sgidp)
158 {
159 	const struct cred *cred = current_cred();
160 	int retval;
161 	u16 rgid, egid, sgid;
162 
163 	rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
164 	egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
165 	sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
166 
167 	if (!(retval   = put_user(rgid, rgidp)) &&
168 	    !(retval   = put_user(egid, egidp)))
169 		retval = put_user(sgid, sgidp);
170 
171 	return retval;
172 }
173 
174 asmlinkage long sys32_setfsuid16(u16 uid)
175 {
176 	return sys_setfsuid((uid_t)uid);
177 }
178 
179 asmlinkage long sys32_setfsgid16(u16 gid)
180 {
181 	return sys_setfsgid((gid_t)gid);
182 }
183 
184 static int groups16_to_user(u16 __user *grouplist, struct group_info *group_info)
185 {
186 	struct user_namespace *user_ns = current_user_ns();
187 	int i;
188 	u16 group;
189 	kgid_t kgid;
190 
191 	for (i = 0; i < group_info->ngroups; i++) {
192 		kgid = GROUP_AT(group_info, i);
193 		group = (u16)from_kgid_munged(user_ns, kgid);
194 		if (put_user(group, grouplist+i))
195 			return -EFAULT;
196 	}
197 
198 	return 0;
199 }
200 
201 static int groups16_from_user(struct group_info *group_info, u16 __user *grouplist)
202 {
203 	struct user_namespace *user_ns = current_user_ns();
204 	int i;
205 	u16 group;
206 	kgid_t kgid;
207 
208 	for (i = 0; i < group_info->ngroups; i++) {
209 		if (get_user(group, grouplist+i))
210 			return  -EFAULT;
211 
212 		kgid = make_kgid(user_ns, (gid_t)group);
213 		if (!gid_valid(kgid))
214 			return -EINVAL;
215 
216 		GROUP_AT(group_info, i) = kgid;
217 	}
218 
219 	return 0;
220 }
221 
222 asmlinkage long sys32_getgroups16(int gidsetsize, u16 __user *grouplist)
223 {
224 	int i;
225 
226 	if (gidsetsize < 0)
227 		return -EINVAL;
228 
229 	get_group_info(current->cred->group_info);
230 	i = current->cred->group_info->ngroups;
231 	if (gidsetsize) {
232 		if (i > gidsetsize) {
233 			i = -EINVAL;
234 			goto out;
235 		}
236 		if (groups16_to_user(grouplist, current->cred->group_info)) {
237 			i = -EFAULT;
238 			goto out;
239 		}
240 	}
241 out:
242 	put_group_info(current->cred->group_info);
243 	return i;
244 }
245 
246 asmlinkage long sys32_setgroups16(int gidsetsize, u16 __user *grouplist)
247 {
248 	struct group_info *group_info;
249 	int retval;
250 
251 	if (!capable(CAP_SETGID))
252 		return -EPERM;
253 	if ((unsigned)gidsetsize > NGROUPS_MAX)
254 		return -EINVAL;
255 
256 	group_info = groups_alloc(gidsetsize);
257 	if (!group_info)
258 		return -ENOMEM;
259 	retval = groups16_from_user(group_info, grouplist);
260 	if (retval) {
261 		put_group_info(group_info);
262 		return retval;
263 	}
264 
265 	retval = set_current_groups(group_info);
266 	put_group_info(group_info);
267 
268 	return retval;
269 }
270 
271 asmlinkage long sys32_getuid16(void)
272 {
273 	return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
274 }
275 
276 asmlinkage long sys32_geteuid16(void)
277 {
278 	return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
279 }
280 
281 asmlinkage long sys32_getgid16(void)
282 {
283 	return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
284 }
285 
286 asmlinkage long sys32_getegid16(void)
287 {
288 	return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
289 }
290 
291 /*
292  * sys32_ipc() is the de-multiplexer for the SysV IPC calls in 32bit emulation.
293  *
294  * This is really horribly ugly.
295  */
296 #ifdef CONFIG_SYSVIPC
297 asmlinkage long sys32_ipc(u32 call, int first, int second, int third, u32 ptr)
298 {
299 	if (call >> 16)		/* hack for backward compatibility */
300 		return -EINVAL;
301 	switch (call) {
302 	case SEMTIMEDOP:
303 		return compat_sys_semtimedop(first, compat_ptr(ptr),
304 					     second, compat_ptr(third));
305 	case SEMOP:
306 		/* struct sembuf is the same on 32 and 64bit :)) */
307 		return sys_semtimedop(first, compat_ptr(ptr),
308 				      second, NULL);
309 	case SEMGET:
310 		return sys_semget(first, second, third);
311 	case SEMCTL:
312 		return compat_sys_semctl(first, second, third,
313 					 compat_ptr(ptr));
314 	case MSGSND:
315 		return compat_sys_msgsnd(first, second, third,
316 					 compat_ptr(ptr));
317 	case MSGRCV:
318 		return compat_sys_msgrcv(first, second, 0, third,
319 					 0, compat_ptr(ptr));
320 	case MSGGET:
321 		return sys_msgget((key_t) first, second);
322 	case MSGCTL:
323 		return compat_sys_msgctl(first, second, compat_ptr(ptr));
324 	case SHMAT:
325 		return compat_sys_shmat(first, second, third,
326 					0, compat_ptr(ptr));
327 	case SHMDT:
328 		return sys_shmdt(compat_ptr(ptr));
329 	case SHMGET:
330 		return sys_shmget(first, (unsigned)second, third);
331 	case SHMCTL:
332 		return compat_sys_shmctl(first, second, compat_ptr(ptr));
333 	}
334 
335 	return -ENOSYS;
336 }
337 #endif
338 
339 asmlinkage long sys32_truncate64(const char __user * path, unsigned long high, unsigned long low)
340 {
341 	if ((int)high < 0)
342 		return -EINVAL;
343 	else
344 		return sys_truncate(path, (high << 32) | low);
345 }
346 
347 asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long high, unsigned long low)
348 {
349 	if ((int)high < 0)
350 		return -EINVAL;
351 	else
352 		return sys_ftruncate(fd, (high << 32) | low);
353 }
354 
355 asmlinkage long sys32_sched_rr_get_interval(compat_pid_t pid,
356 				struct compat_timespec __user *interval)
357 {
358 	struct timespec t;
359 	int ret;
360 	mm_segment_t old_fs = get_fs ();
361 
362 	set_fs (KERNEL_DS);
363 	ret = sys_sched_rr_get_interval(pid,
364 					(struct timespec __force __user *) &t);
365 	set_fs (old_fs);
366 	if (put_compat_timespec(&t, interval))
367 		return -EFAULT;
368 	return ret;
369 }
370 
371 asmlinkage long sys32_rt_sigprocmask(int how, compat_sigset_t __user *set,
372 			compat_sigset_t __user *oset, size_t sigsetsize)
373 {
374 	sigset_t s;
375 	compat_sigset_t s32;
376 	int ret;
377 	mm_segment_t old_fs = get_fs();
378 
379 	if (set) {
380 		if (copy_from_user (&s32, set, sizeof(compat_sigset_t)))
381 			return -EFAULT;
382 		s.sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
383 	}
384 	set_fs (KERNEL_DS);
385 	ret = sys_rt_sigprocmask(how,
386 				 set ? (sigset_t __force __user *) &s : NULL,
387 				 oset ? (sigset_t __force __user *) &s : NULL,
388 				 sigsetsize);
389 	set_fs (old_fs);
390 	if (ret) return ret;
391 	if (oset) {
392 		s32.sig[1] = (s.sig[0] >> 32);
393 		s32.sig[0] = s.sig[0];
394 		if (copy_to_user (oset, &s32, sizeof(compat_sigset_t)))
395 			return -EFAULT;
396 	}
397 	return 0;
398 }
399 
400 asmlinkage long sys32_rt_sigpending(compat_sigset_t __user *set,
401 				size_t sigsetsize)
402 {
403 	sigset_t s;
404 	compat_sigset_t s32;
405 	int ret;
406 	mm_segment_t old_fs = get_fs();
407 
408 	set_fs (KERNEL_DS);
409 	ret = sys_rt_sigpending((sigset_t __force __user *) &s, sigsetsize);
410 	set_fs (old_fs);
411 	if (!ret) {
412 		s32.sig[1] = (s.sig[0] >> 32);
413 		s32.sig[0] = s.sig[0];
414 		if (copy_to_user (set, &s32, sizeof(compat_sigset_t)))
415 			return -EFAULT;
416 	}
417 	return ret;
418 }
419 
420 asmlinkage long
421 sys32_rt_sigqueueinfo(int pid, int sig, compat_siginfo_t __user *uinfo)
422 {
423 	siginfo_t info;
424 	int ret;
425 	mm_segment_t old_fs = get_fs();
426 
427 	if (copy_siginfo_from_user32(&info, uinfo))
428 		return -EFAULT;
429 	set_fs (KERNEL_DS);
430 	ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __force __user *) &info);
431 	set_fs (old_fs);
432 	return ret;
433 }
434 
435 asmlinkage long sys32_pread64(unsigned int fd, char __user *ubuf,
436 				size_t count, u32 poshi, u32 poslo)
437 {
438 	if ((compat_ssize_t) count < 0)
439 		return -EINVAL;
440 	return sys_pread64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
441 }
442 
443 asmlinkage long sys32_pwrite64(unsigned int fd, const char __user *ubuf,
444 				size_t count, u32 poshi, u32 poslo)
445 {
446 	if ((compat_ssize_t) count < 0)
447 		return -EINVAL;
448 	return sys_pwrite64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
449 }
450 
451 asmlinkage compat_ssize_t sys32_readahead(int fd, u32 offhi, u32 offlo, s32 count)
452 {
453 	return sys_readahead(fd, ((loff_t)AA(offhi) << 32) | AA(offlo), count);
454 }
455 
456 asmlinkage long sys32_sendfile(int out_fd, int in_fd, compat_off_t __user *offset, size_t count)
457 {
458 	mm_segment_t old_fs = get_fs();
459 	int ret;
460 	off_t of;
461 
462 	if (offset && get_user(of, offset))
463 		return -EFAULT;
464 
465 	set_fs(KERNEL_DS);
466 	ret = sys_sendfile(out_fd, in_fd,
467 			   offset ? (off_t __force __user *) &of : NULL, count);
468 	set_fs(old_fs);
469 
470 	if (offset && put_user(of, offset))
471 		return -EFAULT;
472 
473 	return ret;
474 }
475 
476 asmlinkage long sys32_sendfile64(int out_fd, int in_fd,
477 				compat_loff_t __user *offset, s32 count)
478 {
479 	mm_segment_t old_fs = get_fs();
480 	int ret;
481 	loff_t lof;
482 
483 	if (offset && get_user(lof, offset))
484 		return -EFAULT;
485 
486 	set_fs(KERNEL_DS);
487 	ret = sys_sendfile64(out_fd, in_fd,
488 			     offset ? (loff_t __force __user *) &lof : NULL,
489 			     count);
490 	set_fs(old_fs);
491 
492 	if (offset && put_user(lof, offset))
493 		return -EFAULT;
494 
495 	return ret;
496 }
497 
498 struct stat64_emu31 {
499 	unsigned long long  st_dev;
500 	unsigned int    __pad1;
501 #define STAT64_HAS_BROKEN_ST_INO        1
502 	u32             __st_ino;
503 	unsigned int    st_mode;
504 	unsigned int    st_nlink;
505 	u32             st_uid;
506 	u32             st_gid;
507 	unsigned long long  st_rdev;
508 	unsigned int    __pad3;
509 	long            st_size;
510 	u32             st_blksize;
511 	unsigned char   __pad4[4];
512 	u32             __pad5;     /* future possible st_blocks high bits */
513 	u32             st_blocks;  /* Number 512-byte blocks allocated. */
514 	u32             st_atime;
515 	u32             __pad6;
516 	u32             st_mtime;
517 	u32             __pad7;
518 	u32             st_ctime;
519 	u32             __pad8;     /* will be high 32 bits of ctime someday */
520 	unsigned long   st_ino;
521 };
522 
523 static int cp_stat64(struct stat64_emu31 __user *ubuf, struct kstat *stat)
524 {
525 	struct stat64_emu31 tmp;
526 
527 	memset(&tmp, 0, sizeof(tmp));
528 
529 	tmp.st_dev = huge_encode_dev(stat->dev);
530 	tmp.st_ino = stat->ino;
531 	tmp.__st_ino = (u32)stat->ino;
532 	tmp.st_mode = stat->mode;
533 	tmp.st_nlink = (unsigned int)stat->nlink;
534 	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
535 	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
536 	tmp.st_rdev = huge_encode_dev(stat->rdev);
537 	tmp.st_size = stat->size;
538 	tmp.st_blksize = (u32)stat->blksize;
539 	tmp.st_blocks = (u32)stat->blocks;
540 	tmp.st_atime = (u32)stat->atime.tv_sec;
541 	tmp.st_mtime = (u32)stat->mtime.tv_sec;
542 	tmp.st_ctime = (u32)stat->ctime.tv_sec;
543 
544 	return copy_to_user(ubuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
545 }
546 
547 asmlinkage long sys32_stat64(const char __user * filename, struct stat64_emu31 __user * statbuf)
548 {
549 	struct kstat stat;
550 	int ret = vfs_stat(filename, &stat);
551 	if (!ret)
552 		ret = cp_stat64(statbuf, &stat);
553 	return ret;
554 }
555 
556 asmlinkage long sys32_lstat64(const char __user * filename, struct stat64_emu31 __user * statbuf)
557 {
558 	struct kstat stat;
559 	int ret = vfs_lstat(filename, &stat);
560 	if (!ret)
561 		ret = cp_stat64(statbuf, &stat);
562 	return ret;
563 }
564 
565 asmlinkage long sys32_fstat64(unsigned long fd, struct stat64_emu31 __user * statbuf)
566 {
567 	struct kstat stat;
568 	int ret = vfs_fstat(fd, &stat);
569 	if (!ret)
570 		ret = cp_stat64(statbuf, &stat);
571 	return ret;
572 }
573 
574 asmlinkage long sys32_fstatat64(unsigned int dfd, const char __user *filename,
575 				struct stat64_emu31 __user* statbuf, int flag)
576 {
577 	struct kstat stat;
578 	int error;
579 
580 	error = vfs_fstatat(dfd, filename, &stat, flag);
581 	if (error)
582 		return error;
583 	return cp_stat64(statbuf, &stat);
584 }
585 
586 /*
587  * Linux/i386 didn't use to be able to handle more than
588  * 4 system call parameters, so these system calls used a memory
589  * block for parameter passing..
590  */
591 
592 struct mmap_arg_struct_emu31 {
593 	compat_ulong_t addr;
594 	compat_ulong_t len;
595 	compat_ulong_t prot;
596 	compat_ulong_t flags;
597 	compat_ulong_t fd;
598 	compat_ulong_t offset;
599 };
600 
601 asmlinkage unsigned long old32_mmap(struct mmap_arg_struct_emu31 __user *arg)
602 {
603 	struct mmap_arg_struct_emu31 a;
604 
605 	if (copy_from_user(&a, arg, sizeof(a)))
606 		return -EFAULT;
607 	if (a.offset & ~PAGE_MASK)
608 		return -EINVAL;
609 	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
610 			      a.offset >> PAGE_SHIFT);
611 }
612 
613 asmlinkage long sys32_mmap2(struct mmap_arg_struct_emu31 __user *arg)
614 {
615 	struct mmap_arg_struct_emu31 a;
616 
617 	if (copy_from_user(&a, arg, sizeof(a)))
618 		return -EFAULT;
619 	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
620 }
621 
622 asmlinkage long sys32_read(unsigned int fd, char __user * buf, size_t count)
623 {
624 	if ((compat_ssize_t) count < 0)
625 		return -EINVAL;
626 
627 	return sys_read(fd, buf, count);
628 }
629 
630 asmlinkage long sys32_write(unsigned int fd, const char __user * buf, size_t count)
631 {
632 	if ((compat_ssize_t) count < 0)
633 		return -EINVAL;
634 
635 	return sys_write(fd, buf, count);
636 }
637 
638 /*
639  * 31 bit emulation wrapper functions for sys_fadvise64/fadvise64_64.
640  * These need to rewrite the advise values for POSIX_FADV_{DONTNEED,NOREUSE}
641  * because the 31 bit values differ from the 64 bit values.
642  */
643 
644 asmlinkage long
645 sys32_fadvise64(int fd, loff_t offset, size_t len, int advise)
646 {
647 	if (advise == 4)
648 		advise = POSIX_FADV_DONTNEED;
649 	else if (advise == 5)
650 		advise = POSIX_FADV_NOREUSE;
651 	return sys_fadvise64(fd, offset, len, advise);
652 }
653 
654 struct fadvise64_64_args {
655 	int fd;
656 	long long offset;
657 	long long len;
658 	int advice;
659 };
660 
661 asmlinkage long
662 sys32_fadvise64_64(struct fadvise64_64_args __user *args)
663 {
664 	struct fadvise64_64_args a;
665 
666 	if ( copy_from_user(&a, args, sizeof(a)) )
667 		return -EFAULT;
668 	if (a.advice == 4)
669 		a.advice = POSIX_FADV_DONTNEED;
670 	else if (a.advice == 5)
671 		a.advice = POSIX_FADV_NOREUSE;
672 	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
673 }
674