xref: /netbsd-src/sys/compat/linux/common/linux_file64.c (revision bfb6cb13d599546df69c7e4d20d70e22e15a549d)
1 /*	$NetBSD: linux_file64.c,v 1.39 2007/05/12 23:02:49 dsl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1998, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank van der Linden and Eric Haszlakiewicz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Linux 64bit filesystem calls. Used on 32bit archs, not used on 64bit ones.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: linux_file64.c,v 1.39 2007/05/12 23:02:49 dsl Exp $");
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/namei.h>
49 #include <sys/proc.h>
50 #include <sys/dirent.h>
51 #include <sys/file.h>
52 #include <sys/stat.h>
53 #include <sys/filedesc.h>
54 #include <sys/ioctl.h>
55 #include <sys/kernel.h>
56 #include <sys/mount.h>
57 #include <sys/malloc.h>
58 #include <sys/namei.h>
59 #include <sys/vfs_syscalls.h>
60 #include <sys/vnode.h>
61 #include <sys/tty.h>
62 #include <sys/conf.h>
63 
64 #include <sys/syscallargs.h>
65 
66 #include <compat/linux/common/linux_types.h>
67 #include <compat/linux/common/linux_signal.h>
68 #include <compat/linux/common/linux_fcntl.h>
69 #include <compat/linux/common/linux_util.h>
70 #include <compat/linux/common/linux_machdep.h>
71 #include <compat/linux/common/linux_dirent.h>
72 
73 #include <compat/linux/linux_syscallargs.h>
74 
75 #ifndef alpha
76 
77 # ifndef COMPAT_LINUX32
78 
79 static void bsd_to_linux_stat __P((struct stat *, struct linux_stat64 *));
80 static int linux_do_stat64 __P((struct lwp *, void *, register_t *, int));
81 
82 /*
83  * Convert a NetBSD stat structure to a Linux stat structure.
84  * Only the order of the fields and the padding in the structure
85  * is different. linux_fakedev is a machine-dependent function
86  * which optionally converts device driver major/minor numbers
87  * (XXX horrible, but what can you do against code that compares
88  * things against constant major device numbers? sigh)
89  */
90 static void
91 bsd_to_linux_stat(bsp, lsp)
92 	struct stat *bsp;
93 	struct linux_stat64 *lsp;
94 {
95 	lsp->lst_dev     = linux_fakedev(bsp->st_dev, 0);
96 	lsp->lst_ino     = bsp->st_ino;
97 	lsp->lst_mode    = (linux_mode_t)bsp->st_mode;
98 	if (bsp->st_nlink >= (1 << 15))
99 		lsp->lst_nlink = (1 << 15) - 1;
100 	else
101 		lsp->lst_nlink = (linux_nlink_t)bsp->st_nlink;
102 	lsp->lst_uid     = bsp->st_uid;
103 	lsp->lst_gid     = bsp->st_gid;
104 	lsp->lst_rdev    = linux_fakedev(bsp->st_rdev, 1);
105 	lsp->lst_size    = bsp->st_size;
106 	lsp->lst_blksize = bsp->st_blksize;
107 	lsp->lst_blocks  = bsp->st_blocks;
108 	lsp->lst_atime   = bsp->st_atime;
109 	lsp->lst_mtime   = bsp->st_mtime;
110 	lsp->lst_ctime   = bsp->st_ctime;
111 #  ifdef LINUX_STAT64_HAS_NSEC
112 	lsp->lst_atime_nsec   = bsp->st_atimensec;
113 	lsp->lst_mtime_nsec   = bsp->st_mtimensec;
114 	lsp->lst_ctime_nsec   = bsp->st_ctimensec;
115 #  endif
116 #  if LINUX_STAT64_HAS_BROKEN_ST_INO
117 	lsp->__lst_ino   = (linux_ino_t) bsp->st_ino;
118 #  endif
119 }
120 
121 /*
122  * The stat functions below are plain sailing. stat and lstat are handled
123  * by one function to avoid code duplication.
124  */
125 int
126 linux_sys_fstat64(l, v, retval)
127 	struct lwp *l;
128 	void *v;
129 	register_t *retval;
130 {
131 	struct linux_sys_fstat64_args /* {
132 		syscallarg(int) fd;
133 		syscallarg(struct linux_stat64 *) sp;
134 	} */ *uap = v;
135 	struct linux_stat64 tmplst;
136 	struct stat tmpst;
137 	int error;
138 
139 	error = do_sys_fstat(l,  SCARG(uap, fd), &tmpst);
140 	if (error != 0)
141 		return error;
142 
143 	bsd_to_linux_stat(&tmpst, &tmplst);
144 
145 	return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst);
146 }
147 
148 static int
149 linux_do_stat64(l, v, retval, flags)
150 	struct lwp *l;
151 	void *v;
152 	register_t *retval;
153 	int flags;
154 {
155 	struct linux_stat64 tmplst;
156 	struct stat tmpst;
157 	int error;
158 	struct linux_sys_stat64_args *uap = v;
159 
160 	error = do_sys_stat(l, SCARG(uap, path), flags, &tmpst);
161 	if (error != 0)
162 		return error;
163 
164 	bsd_to_linux_stat(&tmpst, &tmplst);
165 
166 	return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst);
167 }
168 
169 int
170 linux_sys_stat64(l, v, retval)
171 	struct lwp *l;
172 	void *v;
173 	register_t *retval;
174 {
175 	struct linux_sys_stat64_args /* {
176 		syscallarg(const char *) path;
177 		syscallarg(struct linux_stat64 *) sp;
178 	} */ *uap = v;
179 
180 	return linux_do_stat64(l, uap, retval, FOLLOW);
181 }
182 
183 int
184 linux_sys_lstat64(l, v, retval)
185 	struct lwp *l;
186 	void *v;
187 	register_t *retval;
188 {
189 	struct linux_sys_lstat64_args /* {
190 		syscallarg(const char *) path;
191 		syscallarg(struct linux_stat64 *) sp;
192 	} */ *uap = v;
193 
194 	return linux_do_stat64(l, uap, retval, NOFOLLOW);
195 }
196 
197 int
198 linux_sys_truncate64(l, v, retval)
199 	struct lwp *l;
200 	void *v;
201 	register_t *retval;
202 {
203 	struct linux_sys_truncate64_args /* {
204 		syscallarg(const char *) path;
205 		syscallarg(off_t) length;
206 	} */ *uap = v;
207 	struct sys_truncate_args ta;
208 
209 	/* Linux doesn't have the 'pad' pseudo-parameter */
210 	SCARG(&ta, path) = SCARG(uap, path);
211 	SCARG(&ta, pad) = 0;
212 	SCARG(&ta, length) = SCARG(uap, length);
213 
214 	return sys_truncate(l, &ta, retval);
215 }
216 
217 int
218 linux_sys_ftruncate64(l, v, retval)
219 	struct lwp *l;
220 	void *v;
221 	register_t *retval;
222 {
223 	struct linux_sys_ftruncate64_args /* {
224 		syscallarg(unsigned int) fd;
225 		syscallarg(off_t) length;
226 	} */ *uap = v;
227 	struct sys_ftruncate_args ta;
228 
229 	/* Linux doesn't have the 'pad' pseudo-parameter */
230 	SCARG(&ta, fd) = SCARG(uap, fd);
231 	SCARG(&ta, pad) = 0;
232 	SCARG(&ta, length) = SCARG(uap, length);
233 
234 	return sys_ftruncate(l, &ta, retval);
235 }
236 # endif /* !COMPAT_LINUX32 */
237 
238 # if !defined(__m68k__) && (!defined(__amd64__) || defined(COMPAT_LINUX32))
239 static void bsd_to_linux_flock64 __P((struct linux_flock64 *,
240     const struct flock *));
241 static void linux_to_bsd_flock64 __P((struct flock *,
242     const struct linux_flock64 *));
243 
244 static void
245 bsd_to_linux_flock64(lfp, bfp)
246 	struct linux_flock64 *lfp;
247 	const struct flock *bfp;
248 {
249 
250 	lfp->l_start = bfp->l_start;
251 	lfp->l_len = bfp->l_len;
252 	lfp->l_pid = bfp->l_pid;
253 	lfp->l_whence = bfp->l_whence;
254 	switch (bfp->l_type) {
255 	case F_RDLCK:
256 		lfp->l_type = LINUX_F_RDLCK;
257 		break;
258 	case F_UNLCK:
259 		lfp->l_type = LINUX_F_UNLCK;
260 		break;
261 	case F_WRLCK:
262 		lfp->l_type = LINUX_F_WRLCK;
263 		break;
264 	}
265 }
266 
267 static void
268 linux_to_bsd_flock64(bfp, lfp)
269 	struct flock *bfp;
270 	const struct linux_flock64 *lfp;
271 {
272 
273 	bfp->l_start = lfp->l_start;
274 	bfp->l_len = lfp->l_len;
275 	bfp->l_pid = lfp->l_pid;
276 	bfp->l_whence = lfp->l_whence;
277 	switch (lfp->l_type) {
278 	case LINUX_F_RDLCK:
279 		bfp->l_type = F_RDLCK;
280 		break;
281 	case LINUX_F_UNLCK:
282 		bfp->l_type = F_UNLCK;
283 		break;
284 	case LINUX_F_WRLCK:
285 		bfp->l_type = F_WRLCK;
286 		break;
287 	}
288 }
289 
290 int
291 linux_sys_fcntl64(l, v, retval)
292 	struct lwp *l;
293 	void *v;
294 	register_t *retval;
295 {
296 	struct linux_sys_fcntl64_args /* {
297 		syscallarg(int) fd;
298 		syscallarg(int) cmd;
299 		syscallarg(void *) arg;
300 	} */ *uap = v;
301 	struct linux_flock64 lfl;
302 	struct flock bfl;
303 	int error;
304 	void *arg = SCARG(uap, arg);
305 	int cmd = SCARG(uap, cmd);
306 	int fd = SCARG(uap, fd);
307 
308 	switch (cmd) {
309 	case LINUX_F_GETLK64:
310 		if ((error = copyin(arg, &lfl, sizeof lfl)) != 0)
311 			return error;
312 		linux_to_bsd_flock64(&bfl, &lfl);
313 		error = do_fcntl_lock(l, fd, F_GETLK, &bfl);
314 		if (error != 0)
315 			return error;
316 		bsd_to_linux_flock64(&lfl, &bfl);
317 		return copyout(&lfl, arg, sizeof lfl);
318 	case LINUX_F_SETLK64:
319 	case LINUX_F_SETLKW64:
320 		cmd = (cmd == LINUX_F_SETLK64 ? F_SETLK : F_SETLKW);
321 		if ((error = copyin(arg, &lfl, sizeof lfl)) != 0)
322 			return error;
323 		linux_to_bsd_flock64(&bfl, &lfl);
324 		return do_fcntl_lock(l, fd, cmd, &bfl);
325 	default:
326 		return linux_sys_fcntl(l, v, retval);
327 	}
328 }
329 # endif /* !m69k && !amd64  && !COMPAT_LINUX32 */
330 
331 #endif /* !alpha */
332 
333 /*
334  * Linux 'readdir' call. This code is mostly taken from the
335  * SunOS getdents call (see compat/sunos/sunos_misc.c), though
336  * an attempt has been made to keep it a little cleaner.
337  *
338  * The d_off field contains the offset of the next valid entry,
339  * unless the older Linux getdents(2), which used to have it set
340  * to the offset of the entry itself. This function also doesn't
341  * need to deal with the old count == 1 glibc problem.
342  *
343  * Read in BSD-style entries, convert them, and copy them out.
344  *
345  * Note that this doesn't handle union-mounted filesystems.
346  */
347 #ifndef COMPAT_LINUX32
348 int
349 linux_sys_getdents64(l, v, retval)
350 	struct lwp *l;
351 	void *v;
352 	register_t *retval;
353 {
354 	struct linux_sys_getdents_args /* {
355 		syscallarg(int) fd;
356 		syscallarg(struct linux_dirent64 *) dent;
357 		syscallarg(unsigned int) count;
358 	} */ *uap = v;
359 	struct dirent *bdp;
360 	struct vnode *vp;
361 	char *inp, *tbuf;		/* BSD-format */
362 	int len, reclen;		/* BSD-format */
363 	char *outp;			/* Linux-format */
364 	int resid, linux_reclen = 0;	/* Linux-format */
365 	struct file *fp;
366 	struct uio auio;
367 	struct iovec aiov;
368 	struct linux_dirent64 idb;
369 	off_t off;		/* true file offset */
370 	int buflen, error, eofflag, nbytes;
371 	struct vattr va;
372 	off_t *cookiebuf = NULL, *cookie;
373 	int ncookies;
374 
375 	/* getvnode() will use the descriptor for us */
376 	if ((error = getvnode(l->l_proc->p_fd, SCARG(uap, fd), &fp)) != 0)
377 		return (error);
378 
379 	if ((fp->f_flag & FREAD) == 0) {
380 		error = EBADF;
381 		goto out1;
382 	}
383 
384 	vp = (struct vnode *)fp->f_data;
385 	if (vp->v_type != VDIR) {
386 		error = EINVAL;
387 		goto out1;
388 	}
389 
390 	if ((error = VOP_GETATTR(vp, &va, l->l_cred, l)))
391 		goto out1;
392 
393 	nbytes = SCARG(uap, count);
394 	buflen = min(MAXBSIZE, nbytes);
395 	if (buflen < va.va_blocksize)
396 		buflen = va.va_blocksize;
397 	tbuf = malloc(buflen, M_TEMP, M_WAITOK);
398 
399 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
400 	off = fp->f_offset;
401 again:
402 	aiov.iov_base = tbuf;
403 	aiov.iov_len = buflen;
404 	auio.uio_iov = &aiov;
405 	auio.uio_iovcnt = 1;
406 	auio.uio_rw = UIO_READ;
407 	auio.uio_resid = buflen;
408 	auio.uio_offset = off;
409 	UIO_SETUP_SYSSPACE(&auio);
410 	/*
411          * First we read into the malloc'ed buffer, then
412          * we massage it into user space, one record at a time.
413          */
414 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
415 	    &ncookies);
416 	if (error)
417 		goto out;
418 
419 	inp = tbuf;
420 	outp = (void *)SCARG(uap, dent);
421 	resid = nbytes;
422 	if ((len = buflen - auio.uio_resid) == 0)
423 		goto eof;
424 
425 	for (cookie = cookiebuf; len > 0; len -= reclen) {
426 		bdp = (struct dirent *)inp;
427 		reclen = bdp->d_reclen;
428 		if (reclen & 3)
429 			panic("linux_readdir");
430 		if (bdp->d_fileno == 0) {
431 			inp += reclen;	/* it is a hole; squish it out */
432 			if (cookie)
433 				off = *cookie++;
434 			else
435 				off += reclen;
436 			continue;
437 		}
438 		linux_reclen = LINUX_RECLEN(&idb, bdp->d_namlen);
439 		if (reclen > len || resid < linux_reclen) {
440 			/* entry too big for buffer, so just stop */
441 			outp++;
442 			break;
443 		}
444 		if (cookie)
445 			off = *cookie++;	/* each entry points to next */
446 		else
447 			off += reclen;
448 		/*
449 		 * Massage in place to make a Linux-shaped dirent (otherwise
450 		 * we have to worry about touching user memory outside of
451 		 * the copyout() call).
452 		 */
453 		idb.d_ino = bdp->d_fileno;
454 		idb.d_type = bdp->d_type;
455 		idb.d_off = off;
456 		idb.d_reclen = (u_short)linux_reclen;
457 		strcpy(idb.d_name, bdp->d_name);
458 		if ((error = copyout((void *)&idb, outp, linux_reclen)))
459 			goto out;
460 		/* advance past this real entry */
461 		inp += reclen;
462 		/* advance output past Linux-shaped entry */
463 		outp += linux_reclen;
464 		resid -= linux_reclen;
465 	}
466 
467 	/* if we squished out the whole block, try again */
468 	if (outp == (void *)SCARG(uap, dent))
469 		goto again;
470 	fp->f_offset = off;	/* update the vnode offset */
471 
472 eof:
473 	*retval = nbytes - resid;
474 out:
475 	VOP_UNLOCK(vp, 0);
476 	if (cookiebuf)
477 		free(cookiebuf, M_TEMP);
478 	free(tbuf, M_TEMP);
479 out1:
480 	FILE_UNUSE(fp, l);
481 	return error;
482 }
483 #endif /* !COMPAT_LINUX32 */
484