xref: /netbsd-src/sys/compat/linux/common/linux_file64.c (revision 1ffa7b76c40339c17a0fb2a09fac93f287cfc046)
1 /*	$NetBSD: linux_file64.c,v 1.19 2003/01/18 08:02:52 thorpej 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 1.19 2003/01/18 08:02:52 thorpej 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/vnode.h>
59 #include <sys/tty.h>
60 #include <sys/conf.h>
61 
62 #include <sys/sa.h>
63 #include <sys/syscallargs.h>
64 
65 #include <compat/linux/common/linux_types.h>
66 #include <compat/linux/common/linux_signal.h>
67 #include <compat/linux/common/linux_fcntl.h>
68 #include <compat/linux/common/linux_util.h>
69 #include <compat/linux/common/linux_machdep.h>
70 #include <compat/linux/common/linux_dirent.h>
71 
72 #include <compat/linux/linux_syscallargs.h>
73 
74 #ifndef alpha
75 
76 static void bsd_to_linux_stat __P((struct stat *, struct linux_stat64 *));
77 static int linux_do_stat64 __P((struct lwp *, void *, register_t *, int));
78 
79 /*
80  * Convert a NetBSD stat structure to a Linux stat structure.
81  * Only the order of the fields and the padding in the structure
82  * is different. linux_fakedev is a machine-dependent function
83  * which optionally converts device driver major/minor numbers
84  * (XXX horrible, but what can you do against code that compares
85  * things against constant major device numbers? sigh)
86  */
87 static void
88 bsd_to_linux_stat(bsp, lsp)
89 	struct stat *bsp;
90 	struct linux_stat64 *lsp;
91 {
92 	lsp->lst_dev     = linux_fakedev(bsp->st_dev, 0);
93 	lsp->lst_ino     = bsp->st_ino;
94 	lsp->lst_mode    = (linux_mode_t)bsp->st_mode;
95 	if (bsp->st_nlink >= (1 << 15))
96 		lsp->lst_nlink = (1 << 15) - 1;
97 	else
98 		lsp->lst_nlink = (linux_nlink_t)bsp->st_nlink;
99 	lsp->lst_uid     = bsp->st_uid;
100 	lsp->lst_gid     = bsp->st_gid;
101 	lsp->lst_rdev    = linux_fakedev(bsp->st_rdev, 1);
102 	lsp->lst_size    = bsp->st_size;
103 	lsp->lst_blksize = bsp->st_blksize;
104 	lsp->lst_blocks  = bsp->st_blocks;
105 	lsp->lst_atime   = bsp->st_atime;
106 	lsp->lst_mtime   = bsp->st_mtime;
107 	lsp->lst_ctime   = bsp->st_ctime;
108 #if LINUX_STAT64_HAS_BROKEN_ST_INO
109 	lsp->__lst_ino   = (linux_ino_t) bsp->st_ino;
110 #endif
111 }
112 
113 /*
114  * The stat functions below are plain sailing. stat and lstat are handled
115  * by one function to avoid code duplication.
116  */
117 int
118 linux_sys_fstat64(l, v, retval)
119 	struct lwp *l;
120 	void *v;
121 	register_t *retval;
122 {
123 	struct linux_sys_fstat64_args /* {
124 		syscallarg(int) fd;
125 		syscallarg(struct linux_stat64 *) sp;
126 	} */ *uap = v;
127 	struct proc *p = l->l_proc;
128 	struct sys___fstat13_args fsa;
129 	struct linux_stat64 tmplst;
130 	struct stat *st,tmpst;
131 	caddr_t sg;
132 	int error;
133 
134 	sg = stackgap_init(p, 0);
135 
136 	st = stackgap_alloc(p, &sg, sizeof (struct stat));
137 
138 	SCARG(&fsa, fd) = SCARG(uap, fd);
139 	SCARG(&fsa, sb) = st;
140 
141 	if ((error = sys___fstat13(l, &fsa, retval)))
142 		return error;
143 
144 	if ((error = copyin(st, &tmpst, sizeof tmpst)))
145 		return error;
146 
147 	bsd_to_linux_stat(&tmpst, &tmplst);
148 
149 	if ((error = copyout(&tmplst, SCARG(uap, sp), sizeof tmplst)))
150 		return error;
151 
152 	return 0;
153 }
154 
155 static int
156 linux_do_stat64(l, v, retval, dolstat)
157 	struct lwp *l;
158 	void *v;
159 	register_t *retval;
160 	int dolstat;
161 {
162 	struct proc *p = l->l_proc;
163 	struct sys___stat13_args sa;
164 	struct linux_stat64 tmplst;
165 	struct stat *st, tmpst;
166 	caddr_t sg;
167 	int error;
168 	struct linux_sys_stat64_args *uap = v;
169 
170 	sg = stackgap_init(p, 0);
171 	st = stackgap_alloc(p, &sg, sizeof (struct stat));
172 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
173 
174 	SCARG(&sa, ub) = st;
175 	SCARG(&sa, path) = SCARG(uap, path);
176 
177 	if ((error = (dolstat ? sys___lstat13(l, &sa, retval) :
178 				sys___stat13(l, &sa, retval))))
179 		return error;
180 
181 	if ((error = copyin(st, &tmpst, sizeof tmpst)))
182 		return error;
183 
184 	bsd_to_linux_stat(&tmpst, &tmplst);
185 
186 	if ((error = copyout(&tmplst, SCARG(uap, sp), sizeof tmplst)))
187 		return error;
188 
189 	return 0;
190 }
191 
192 int
193 linux_sys_stat64(l, v, retval)
194 	struct lwp *l;
195 	void *v;
196 	register_t *retval;
197 {
198 	struct linux_sys_stat64_args /* {
199 		syscallarg(const char *) path;
200 		syscallarg(struct linux_stat64 *) sp;
201 	} */ *uap = v;
202 
203 	return linux_do_stat64(l, uap, retval, 0);
204 }
205 
206 int
207 linux_sys_lstat64(l, v, retval)
208 	struct lwp *l;
209 	void *v;
210 	register_t *retval;
211 {
212 	struct linux_sys_lstat64_args /* {
213 		syscallarg(const char *) path;
214 		syscallarg(struct linux_stat64 *) sp;
215 	} */ *uap = v;
216 
217 	return linux_do_stat64(l, uap, retval, 1);
218 }
219 
220 int
221 linux_sys_truncate64(l, v, retval)
222 	struct lwp *l;
223 	void *v;
224 	register_t *retval;
225 {
226 	struct linux_sys_truncate64_args /* {
227 		syscallarg(const char *) path;
228 		syscallarg(off_t) length;
229 	} */ *uap = v;
230 	struct proc *p = l->l_proc;
231 	caddr_t sg = stackgap_init(p, 0);
232 
233 	CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
234 
235 	return sys_truncate(l, uap, retval);
236 }
237 
238 #if !defined(__m68k__)
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 proc *p = l->l_proc;
302 	struct sys_fcntl_args fca;
303 	struct linux_flock64 lfl;
304 	struct flock bfl, *bfp;
305 	int error;
306 	caddr_t sg;
307 	void *arg = SCARG(uap, arg);
308 	int cmd = SCARG(uap, cmd);
309 	int fd = SCARG(uap, fd);
310 
311 	switch (cmd) {
312 	case LINUX_F_GETLK64:
313 		sg = stackgap_init(p, 0);
314 		bfp = (struct flock *) stackgap_alloc(p, &sg, sizeof *bfp);
315 		if ((error = copyin(arg, &lfl, sizeof lfl)) != 0)
316 			return error;
317 		linux_to_bsd_flock64(&bfl, &lfl);
318 		if ((error = copyout(&bfl, bfp, sizeof bfl)) != 0)
319 			return error;
320 		SCARG(&fca, fd) = fd;
321 		SCARG(&fca, cmd) = F_GETLK;
322 		SCARG(&fca, arg) = bfp;
323 		if ((error = sys_fcntl(l, &fca, retval)) != 0)
324 			return error;
325 		if ((error = copyin(bfp, &bfl, sizeof bfl)) != 0)
326 			return error;
327 		bsd_to_linux_flock64(&lfl, &bfl);
328 		return copyout(&lfl, arg, sizeof lfl);
329 	case LINUX_F_SETLK64:
330 	case LINUX_F_SETLKW64:
331 		cmd = (cmd == LINUX_F_SETLK64 ? F_SETLK : F_SETLKW);
332 		if ((error = copyin(arg, &lfl, sizeof lfl)) != 0)
333 			return error;
334 		linux_to_bsd_flock64(&bfl, &lfl);
335 		sg = stackgap_init(p, 0);
336 		bfp = (struct flock *) stackgap_alloc(p, &sg, sizeof *bfp);
337 		if ((error = copyout(&bfl, bfp, sizeof bfl)) != 0)
338 			return error;
339 		SCARG(&fca, fd) = fd;
340 		SCARG(&fca, cmd) = cmd;
341 		SCARG(&fca, arg) = bfp;
342 		return sys_fcntl(l, &fca, retval);
343 	default:
344 		return linux_sys_fcntl(l, v, retval);
345 	}
346 }
347 #endif /* !m68k */
348 
349 #endif /* !alpha */
350 
351 /*
352  * Linux 'readdir' call. This code is mostly taken from the
353  * SunOS getdents call (see compat/sunos/sunos_misc.c), though
354  * an attempt has been made to keep it a little cleaner.
355  *
356  * The d_off field contains the offset of the next valid entry,
357  * unless the older Linux getdents(2), which used to have it set
358  * to the offset of the entry itself. This function also doesn't
359  * need to deal with the old count == 1 glibc problem.
360  *
361  * Read in BSD-style entries, convert them, and copy them out.
362  *
363  * Note that this doesn't handle union-mounted filesystems.
364  */
365 int
366 linux_sys_getdents64(l, v, retval)
367 	struct lwp *l;
368 	void *v;
369 	register_t *retval;
370 {
371 	struct linux_sys_getdents_args /* {
372 		syscallarg(int) fd;
373 		syscallarg(struct linux_dirent64 *) dent;
374 		syscallarg(unsigned int) count;
375 	} */ *uap = v;
376 	struct proc *p = l->l_proc;
377 	struct dirent *bdp;
378 	struct vnode *vp;
379 	caddr_t	inp, buf;		/* BSD-format */
380 	int len, reclen;		/* BSD-format */
381 	caddr_t outp;			/* Linux-format */
382 	int resid, linux_reclen = 0;	/* Linux-format */
383 	struct file *fp;
384 	struct uio auio;
385 	struct iovec aiov;
386 	struct linux_dirent64 idb;
387 	off_t off;		/* true file offset */
388 	int buflen, error, eofflag, nbytes;
389 	struct vattr va;
390 	off_t *cookiebuf = NULL, *cookie;
391 	int ncookies;
392 
393 	/* getvnode() will use the descriptor for us */
394 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
395 		return (error);
396 
397 	if ((fp->f_flag & FREAD) == 0) {
398 		error = EBADF;
399 		goto out1;
400 	}
401 
402 	vp = (struct vnode *)fp->f_data;
403 	if (vp->v_type != VDIR) {
404 		error = EINVAL;
405 		goto out1;
406 	}
407 
408 	if ((error = VOP_GETATTR(vp, &va, p->p_ucred, p)))
409 		goto out1;
410 
411 	nbytes = SCARG(uap, count);
412 	buflen = min(MAXBSIZE, nbytes);
413 	if (buflen < va.va_blocksize)
414 		buflen = va.va_blocksize;
415 	buf = malloc(buflen, M_TEMP, M_WAITOK);
416 
417 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
418 	off = fp->f_offset;
419 again:
420 	aiov.iov_base = buf;
421 	aiov.iov_len = buflen;
422 	auio.uio_iov = &aiov;
423 	auio.uio_iovcnt = 1;
424 	auio.uio_rw = UIO_READ;
425 	auio.uio_segflg = UIO_SYSSPACE;
426 	auio.uio_procp = p;
427 	auio.uio_resid = buflen;
428 	auio.uio_offset = off;
429 	/*
430          * First we read into the malloc'ed buffer, then
431          * we massage it into user space, one record at a time.
432          */
433 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf,
434 	    &ncookies);
435 	if (error)
436 		goto out;
437 
438 	inp = buf;
439 	outp = (caddr_t)SCARG(uap, dent);
440 	resid = nbytes;
441 	if ((len = buflen - auio.uio_resid) == 0)
442 		goto eof;
443 
444 	for (cookie = cookiebuf; len > 0; len -= reclen) {
445 		bdp = (struct dirent *)inp;
446 		reclen = bdp->d_reclen;
447 		if (reclen & 3)
448 			panic("linux_readdir");
449 		if (bdp->d_fileno == 0) {
450 			inp += reclen;	/* it is a hole; squish it out */
451 			off = *cookie++;
452 			continue;
453 		}
454 		linux_reclen = LINUX_RECLEN(&idb, bdp->d_namlen);
455 		if (reclen > len || resid < linux_reclen) {
456 			/* entry too big for buffer, so just stop */
457 			outp++;
458 			break;
459 		}
460 		off = *cookie++;	/* each entry points to next */
461 		/*
462 		 * Massage in place to make a Linux-shaped dirent (otherwise
463 		 * we have to worry about touching user memory outside of
464 		 * the copyout() call).
465 		 */
466 		idb.d_ino = bdp->d_fileno;
467 		idb.d_type = bdp->d_type;
468 		idb.d_off = off;
469 		idb.d_reclen = (u_short)linux_reclen;
470 		strcpy(idb.d_name, bdp->d_name);
471 		if ((error = copyout((caddr_t)&idb, outp, linux_reclen)))
472 			goto out;
473 		/* advance past this real entry */
474 		inp += reclen;
475 		/* advance output past Linux-shaped entry */
476 		outp += linux_reclen;
477 		resid -= linux_reclen;
478 	}
479 
480 	/* if we squished out the whole block, try again */
481 	if (outp == (caddr_t)SCARG(uap, dent))
482 		goto again;
483 	fp->f_offset = off;	/* update the vnode offset */
484 
485 eof:
486 	*retval = nbytes - resid;
487 out:
488 	VOP_UNLOCK(vp, 0);
489 	if (cookiebuf)
490 		free(cookiebuf, M_TEMP);
491 	free(buf, M_TEMP);
492 out1:
493 	FILE_UNUSE(fp, p);
494 	return error;
495 }
496