xref: /netbsd-src/sys/compat/linux/common/linux_file64.c (revision 0df165c04d0a9ca1adde9ed2b890344c937954a6)
1 /*	$NetBSD: linux_file64.c,v 1.41 2007/11/26 19:01:31 pooka 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 1.41 2007/11/26 19:01:31 pooka 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 #include <compat/linux/common/linux_ipc.h>
73 #include <compat/linux/common/linux_sem.h>
74 
75 #include <compat/linux/linux_syscallargs.h>
76 
77 #ifndef alpha
78 
79 # ifndef COMPAT_LINUX32
80 
81 static void bsd_to_linux_stat __P((struct stat *, struct linux_stat64 *));
82 static int linux_do_stat64 __P((struct lwp *, void *, register_t *, int));
83 
84 /*
85  * Convert a NetBSD stat structure to a Linux stat structure.
86  * Only the order of the fields and the padding in the structure
87  * is different. linux_fakedev is a machine-dependent function
88  * which optionally converts device driver major/minor numbers
89  * (XXX horrible, but what can you do against code that compares
90  * things against constant major device numbers? sigh)
91  */
92 static void
93 bsd_to_linux_stat(bsp, lsp)
94 	struct stat *bsp;
95 	struct linux_stat64 *lsp;
96 {
97 	lsp->lst_dev     = linux_fakedev(bsp->st_dev, 0);
98 	lsp->lst_ino     = bsp->st_ino;
99 	lsp->lst_mode    = (linux_mode_t)bsp->st_mode;
100 	if (bsp->st_nlink >= (1 << 15))
101 		lsp->lst_nlink = (1 << 15) - 1;
102 	else
103 		lsp->lst_nlink = (linux_nlink_t)bsp->st_nlink;
104 	lsp->lst_uid     = bsp->st_uid;
105 	lsp->lst_gid     = bsp->st_gid;
106 	lsp->lst_rdev    = linux_fakedev(bsp->st_rdev, 1);
107 	lsp->lst_size    = bsp->st_size;
108 	lsp->lst_blksize = bsp->st_blksize;
109 	lsp->lst_blocks  = bsp->st_blocks;
110 	lsp->lst_atime   = bsp->st_atime;
111 	lsp->lst_mtime   = bsp->st_mtime;
112 	lsp->lst_ctime   = bsp->st_ctime;
113 #  ifdef LINUX_STAT64_HAS_NSEC
114 	lsp->lst_atime_nsec   = bsp->st_atimensec;
115 	lsp->lst_mtime_nsec   = bsp->st_mtimensec;
116 	lsp->lst_ctime_nsec   = bsp->st_ctimensec;
117 #  endif
118 #  if LINUX_STAT64_HAS_BROKEN_ST_INO
119 	lsp->__lst_ino   = (linux_ino_t) bsp->st_ino;
120 #  endif
121 }
122 
123 /*
124  * The stat functions below are plain sailing. stat and lstat are handled
125  * by one function to avoid code duplication.
126  */
127 int
128 linux_sys_fstat64(l, v, retval)
129 	struct lwp *l;
130 	void *v;
131 	register_t *retval;
132 {
133 	struct linux_sys_fstat64_args /* {
134 		syscallarg(int) fd;
135 		syscallarg(struct linux_stat64 *) sp;
136 	} */ *uap = v;
137 	struct linux_stat64 tmplst;
138 	struct stat tmpst;
139 	int error;
140 
141 	error = do_sys_fstat(l,  SCARG(uap, fd), &tmpst);
142 	if (error != 0)
143 		return error;
144 
145 	bsd_to_linux_stat(&tmpst, &tmplst);
146 
147 	return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst);
148 }
149 
150 static int
151 linux_do_stat64(l, v, retval, flags)
152 	struct lwp *l;
153 	void *v;
154 	register_t *retval;
155 	int flags;
156 {
157 	struct linux_stat64 tmplst;
158 	struct stat tmpst;
159 	int error;
160 	struct linux_sys_stat64_args *uap = v;
161 
162 	error = do_sys_stat(l, SCARG(uap, path), flags, &tmpst);
163 	if (error != 0)
164 		return error;
165 
166 	bsd_to_linux_stat(&tmpst, &tmplst);
167 
168 	return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst);
169 }
170 
171 int
172 linux_sys_stat64(l, v, retval)
173 	struct lwp *l;
174 	void *v;
175 	register_t *retval;
176 {
177 	struct linux_sys_stat64_args /* {
178 		syscallarg(const char *) path;
179 		syscallarg(struct linux_stat64 *) sp;
180 	} */ *uap = v;
181 
182 	return linux_do_stat64(l, uap, retval, FOLLOW);
183 }
184 
185 int
186 linux_sys_lstat64(l, v, retval)
187 	struct lwp *l;
188 	void *v;
189 	register_t *retval;
190 {
191 	struct linux_sys_lstat64_args /* {
192 		syscallarg(const char *) path;
193 		syscallarg(struct linux_stat64 *) sp;
194 	} */ *uap = v;
195 
196 	return linux_do_stat64(l, uap, retval, NOFOLLOW);
197 }
198 
199 int
200 linux_sys_truncate64(l, v, retval)
201 	struct lwp *l;
202 	void *v;
203 	register_t *retval;
204 {
205 	struct linux_sys_truncate64_args /* {
206 		syscallarg(const char *) path;
207 		syscallarg(off_t) length;
208 	} */ *uap = v;
209 	struct sys_truncate_args ta;
210 
211 	/* Linux doesn't have the 'pad' pseudo-parameter */
212 	SCARG(&ta, path) = SCARG(uap, path);
213 	SCARG(&ta, pad) = 0;
214 	SCARG(&ta, length) = SCARG(uap, length);
215 
216 	return sys_truncate(l, &ta, retval);
217 }
218 
219 int
220 linux_sys_ftruncate64(l, v, retval)
221 	struct lwp *l;
222 	void *v;
223 	register_t *retval;
224 {
225 	struct linux_sys_ftruncate64_args /* {
226 		syscallarg(unsigned int) fd;
227 		syscallarg(off_t) length;
228 	} */ *uap = v;
229 	struct sys_ftruncate_args ta;
230 
231 	/* Linux doesn't have the 'pad' pseudo-parameter */
232 	SCARG(&ta, fd) = SCARG(uap, fd);
233 	SCARG(&ta, pad) = 0;
234 	SCARG(&ta, length) = SCARG(uap, length);
235 
236 	return sys_ftruncate(l, &ta, retval);
237 }
238 # endif /* !COMPAT_LINUX32 */
239 
240 # if !defined(__m68k__) && (!defined(__amd64__) || defined(COMPAT_LINUX32))
241 static void bsd_to_linux_flock64 __P((struct linux_flock64 *,
242     const struct flock *));
243 static void linux_to_bsd_flock64 __P((struct flock *,
244     const struct linux_flock64 *));
245 
246 static void
247 bsd_to_linux_flock64(lfp, bfp)
248 	struct linux_flock64 *lfp;
249 	const struct flock *bfp;
250 {
251 
252 	lfp->l_start = bfp->l_start;
253 	lfp->l_len = bfp->l_len;
254 	lfp->l_pid = bfp->l_pid;
255 	lfp->l_whence = bfp->l_whence;
256 	switch (bfp->l_type) {
257 	case F_RDLCK:
258 		lfp->l_type = LINUX_F_RDLCK;
259 		break;
260 	case F_UNLCK:
261 		lfp->l_type = LINUX_F_UNLCK;
262 		break;
263 	case F_WRLCK:
264 		lfp->l_type = LINUX_F_WRLCK;
265 		break;
266 	}
267 }
268 
269 static void
270 linux_to_bsd_flock64(bfp, lfp)
271 	struct flock *bfp;
272 	const struct linux_flock64 *lfp;
273 {
274 
275 	bfp->l_start = lfp->l_start;
276 	bfp->l_len = lfp->l_len;
277 	bfp->l_pid = lfp->l_pid;
278 	bfp->l_whence = lfp->l_whence;
279 	switch (lfp->l_type) {
280 	case LINUX_F_RDLCK:
281 		bfp->l_type = F_RDLCK;
282 		break;
283 	case LINUX_F_UNLCK:
284 		bfp->l_type = F_UNLCK;
285 		break;
286 	case LINUX_F_WRLCK:
287 		bfp->l_type = F_WRLCK;
288 		break;
289 	}
290 }
291 
292 int
293 linux_sys_fcntl64(l, v, retval)
294 	struct lwp *l;
295 	void *v;
296 	register_t *retval;
297 {
298 	struct linux_sys_fcntl64_args /* {
299 		syscallarg(int) fd;
300 		syscallarg(int) cmd;
301 		syscallarg(void *) arg;
302 	} */ *uap = v;
303 	struct linux_flock64 lfl;
304 	struct flock bfl;
305 	int error;
306 	void *arg = SCARG(uap, arg);
307 	int cmd = SCARG(uap, cmd);
308 	int fd = SCARG(uap, fd);
309 
310 	switch (cmd) {
311 	case LINUX_F_GETLK64:
312 		if ((error = copyin(arg, &lfl, sizeof lfl)) != 0)
313 			return error;
314 		linux_to_bsd_flock64(&bfl, &lfl);
315 		error = do_fcntl_lock(l, fd, F_GETLK, &bfl);
316 		if (error != 0)
317 			return error;
318 		bsd_to_linux_flock64(&lfl, &bfl);
319 		return copyout(&lfl, arg, sizeof lfl);
320 	case LINUX_F_SETLK64:
321 	case LINUX_F_SETLKW64:
322 		cmd = (cmd == LINUX_F_SETLK64 ? F_SETLK : F_SETLKW);
323 		if ((error = copyin(arg, &lfl, sizeof lfl)) != 0)
324 			return error;
325 		linux_to_bsd_flock64(&bfl, &lfl);
326 		return do_fcntl_lock(l, fd, cmd, &bfl);
327 	default:
328 		return linux_sys_fcntl(l, v, retval);
329 	}
330 }
331 # endif /* !m69k && !amd64  && !COMPAT_LINUX32 */
332 
333 #endif /* !alpha */
334 
335 /*
336  * Linux 'readdir' call. This code is mostly taken from the
337  * SunOS getdents call (see compat/sunos/sunos_misc.c), though
338  * an attempt has been made to keep it a little cleaner.
339  *
340  * The d_off field contains the offset of the next valid entry,
341  * unless the older Linux getdents(2), which used to have it set
342  * to the offset of the entry itself. This function also doesn't
343  * need to deal with the old count == 1 glibc problem.
344  *
345  * Read in BSD-style entries, convert them, and copy them out.
346  *
347  * Note that this doesn't handle union-mounted filesystems.
348  */
349 #ifndef COMPAT_LINUX32
350 int
351 linux_sys_getdents64(l, v, retval)
352 	struct lwp *l;
353 	void *v;
354 	register_t *retval;
355 {
356 	struct linux_sys_getdents_args /* {
357 		syscallarg(int) fd;
358 		syscallarg(struct linux_dirent64 *) dent;
359 		syscallarg(unsigned int) count;
360 	} */ *uap = v;
361 	struct dirent *bdp;
362 	struct vnode *vp;
363 	char *inp, *tbuf;		/* BSD-format */
364 	int len, reclen;		/* BSD-format */
365 	char *outp;			/* Linux-format */
366 	int resid, linux_reclen = 0;	/* Linux-format */
367 	struct file *fp;
368 	struct uio auio;
369 	struct iovec aiov;
370 	struct linux_dirent64 idb;
371 	off_t off;		/* true file offset */
372 	int buflen, error, eofflag, nbytes;
373 	struct vattr va;
374 	off_t *cookiebuf = NULL, *cookie;
375 	int ncookies;
376 
377 	/* getvnode() will use the descriptor for us */
378 	if ((error = getvnode(l->l_proc->p_fd, SCARG(uap, fd), &fp)) != 0)
379 		return (error);
380 
381 	if ((fp->f_flag & FREAD) == 0) {
382 		error = EBADF;
383 		goto out1;
384 	}
385 
386 	vp = (struct vnode *)fp->f_data;
387 	if (vp->v_type != VDIR) {
388 		error = EINVAL;
389 		goto out1;
390 	}
391 
392 	if ((error = VOP_GETATTR(vp, &va, l->l_cred)))
393 		goto out1;
394 
395 	nbytes = SCARG(uap, count);
396 	buflen = min(MAXBSIZE, nbytes);
397 	if (buflen < va.va_blocksize)
398 		buflen = va.va_blocksize;
399 	tbuf = malloc(buflen, M_TEMP, M_WAITOK);
400 
401 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
402 	off = fp->f_offset;
403 again:
404 	aiov.iov_base = tbuf;
405 	aiov.iov_len = buflen;
406 	auio.uio_iov = &aiov;
407 	auio.uio_iovcnt = 1;
408 	auio.uio_rw = UIO_READ;
409 	auio.uio_resid = buflen;
410 	auio.uio_offset = off;
411 	UIO_SETUP_SYSSPACE(&auio);
412 	/*
413          * First we read into the malloc'ed buffer, then
414          * we massage it into user space, one record at a time.
415          */
416 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
417 	    &ncookies);
418 	if (error)
419 		goto out;
420 
421 	inp = tbuf;
422 	outp = (void *)SCARG(uap, dent);
423 	resid = nbytes;
424 	if ((len = buflen - auio.uio_resid) == 0)
425 		goto eof;
426 
427 	for (cookie = cookiebuf; len > 0; len -= reclen) {
428 		bdp = (struct dirent *)inp;
429 		reclen = bdp->d_reclen;
430 		if (reclen & 3)
431 			panic("linux_readdir");
432 		if (bdp->d_fileno == 0) {
433 			inp += reclen;	/* it is a hole; squish it out */
434 			if (cookie)
435 				off = *cookie++;
436 			else
437 				off += reclen;
438 			continue;
439 		}
440 		linux_reclen = LINUX_RECLEN(&idb, bdp->d_namlen);
441 		if (reclen > len || resid < linux_reclen) {
442 			/* entry too big for buffer, so just stop */
443 			outp++;
444 			break;
445 		}
446 		if (cookie)
447 			off = *cookie++;	/* each entry points to next */
448 		else
449 			off += reclen;
450 		/*
451 		 * Massage in place to make a Linux-shaped dirent (otherwise
452 		 * we have to worry about touching user memory outside of
453 		 * the copyout() call).
454 		 */
455 		idb.d_ino = bdp->d_fileno;
456 		idb.d_type = bdp->d_type;
457 		idb.d_off = off;
458 		idb.d_reclen = (u_short)linux_reclen;
459 		strcpy(idb.d_name, bdp->d_name);
460 		if ((error = copyout((void *)&idb, outp, linux_reclen)))
461 			goto out;
462 		/* advance past this real entry */
463 		inp += reclen;
464 		/* advance output past Linux-shaped entry */
465 		outp += linux_reclen;
466 		resid -= linux_reclen;
467 	}
468 
469 	/* if we squished out the whole block, try again */
470 	if (outp == (void *)SCARG(uap, dent))
471 		goto again;
472 	fp->f_offset = off;	/* update the vnode offset */
473 
474 eof:
475 	*retval = nbytes - resid;
476 out:
477 	VOP_UNLOCK(vp, 0);
478 	if (cookiebuf)
479 		free(cookiebuf, M_TEMP);
480 	free(tbuf, M_TEMP);
481 out1:
482 	FILE_UNUSE(fp, l);
483 	return error;
484 }
485 #endif /* !COMPAT_LINUX32 */
486