1 | /* $NetBSD: linux_file64.c,v 1.55 2013/12/27 14:17:11 njoly Exp $ */ |
2 | |
3 | /*- |
4 | * Copyright (c) 1995, 1998, 2000, 2008 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 | * |
19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
29 | * POSSIBILITY OF SUCH DAMAGE. |
30 | */ |
31 | |
32 | /* |
33 | * Linux 64bit filesystem calls. Used on 32bit archs, not used on 64bit ones. |
34 | */ |
35 | |
36 | #include <sys/cdefs.h> |
37 | __KERNEL_RCSID(0, "$NetBSD: linux_file64.c,v 1.55 2013/12/27 14:17:11 njoly Exp $" ); |
38 | |
39 | #include <sys/param.h> |
40 | #include <sys/systm.h> |
41 | #include <sys/namei.h> |
42 | #include <sys/proc.h> |
43 | #include <sys/dirent.h> |
44 | #include <sys/file.h> |
45 | #include <sys/stat.h> |
46 | #include <sys/filedesc.h> |
47 | #include <sys/ioctl.h> |
48 | #include <sys/kernel.h> |
49 | #include <sys/mount.h> |
50 | #include <sys/malloc.h> |
51 | #include <sys/namei.h> |
52 | #include <sys/vfs_syscalls.h> |
53 | #include <sys/vnode.h> |
54 | #include <sys/tty.h> |
55 | #include <sys/conf.h> |
56 | |
57 | #include <sys/syscallargs.h> |
58 | |
59 | #include <compat/linux/common/linux_types.h> |
60 | #include <compat/linux/common/linux_signal.h> |
61 | #include <compat/linux/common/linux_fcntl.h> |
62 | #include <compat/linux/common/linux_util.h> |
63 | #include <compat/linux/common/linux_machdep.h> |
64 | #include <compat/linux/common/linux_dirent.h> |
65 | #include <compat/linux/common/linux_ipc.h> |
66 | #include <compat/linux/common/linux_sem.h> |
67 | |
68 | #include <compat/linux/linux_syscallargs.h> |
69 | |
70 | static void bsd_to_linux_stat(struct stat *, struct linux_stat64 *); |
71 | |
72 | /* |
73 | * Convert a NetBSD stat structure to a Linux stat structure. |
74 | * Only the order of the fields and the padding in the structure |
75 | * is different. linux_fakedev is a machine-dependent function |
76 | * which optionally converts device driver major/minor numbers |
77 | * (XXX horrible, but what can you do against code that compares |
78 | * things against constant major device numbers? sigh) |
79 | */ |
80 | static void |
81 | bsd_to_linux_stat(struct stat *bsp, struct linux_stat64 *lsp) |
82 | { |
83 | lsp->lst_dev = linux_fakedev(bsp->st_dev, 0); |
84 | lsp->lst_ino = bsp->st_ino; |
85 | lsp->lst_mode = (linux_mode_t)bsp->st_mode; |
86 | if (bsp->st_nlink >= (1 << 15)) |
87 | lsp->lst_nlink = (1 << 15) - 1; |
88 | else |
89 | lsp->lst_nlink = (linux_nlink_t)bsp->st_nlink; |
90 | lsp->lst_uid = bsp->st_uid; |
91 | lsp->lst_gid = bsp->st_gid; |
92 | lsp->lst_rdev = linux_fakedev(bsp->st_rdev, 1); |
93 | lsp->lst_size = bsp->st_size; |
94 | lsp->lst_blksize = bsp->st_blksize; |
95 | lsp->lst_blocks = bsp->st_blocks; |
96 | lsp->lst_atime = bsp->st_atime; |
97 | lsp->lst_mtime = bsp->st_mtime; |
98 | lsp->lst_ctime = bsp->st_ctime; |
99 | # ifdef LINUX_STAT64_HAS_NSEC |
100 | lsp->lst_atime_nsec = bsp->st_atimensec; |
101 | lsp->lst_mtime_nsec = bsp->st_mtimensec; |
102 | lsp->lst_ctime_nsec = bsp->st_ctimensec; |
103 | # endif |
104 | # if LINUX_STAT64_HAS_BROKEN_ST_INO |
105 | lsp->__lst_ino = (linux_ino_t) bsp->st_ino; |
106 | # endif |
107 | } |
108 | |
109 | /* |
110 | * The stat functions below are plain sailing. stat and lstat are handled |
111 | * by one function to avoid code duplication. |
112 | */ |
113 | int |
114 | linux_sys_fstat64(struct lwp *l, const struct linux_sys_fstat64_args *uap, register_t *retval) |
115 | { |
116 | /* { |
117 | syscallarg(int) fd; |
118 | syscallarg(struct linux_stat64 *) sp; |
119 | } */ |
120 | struct linux_stat64 tmplst; |
121 | struct stat tmpst; |
122 | int error; |
123 | |
124 | error = do_sys_fstat(SCARG(uap, fd), &tmpst); |
125 | if (error != 0) |
126 | return error; |
127 | |
128 | bsd_to_linux_stat(&tmpst, &tmplst); |
129 | |
130 | return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); |
131 | } |
132 | |
133 | static int |
134 | linux_do_stat64(struct lwp *l, const struct linux_sys_stat64_args *uap, register_t *retval, int flags) |
135 | { |
136 | struct linux_stat64 tmplst; |
137 | struct stat tmpst; |
138 | int error; |
139 | |
140 | error = do_sys_stat(SCARG(uap, path), flags, &tmpst); |
141 | if (error != 0) |
142 | return error; |
143 | |
144 | bsd_to_linux_stat(&tmpst, &tmplst); |
145 | |
146 | return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); |
147 | } |
148 | |
149 | int |
150 | linux_sys_stat64(struct lwp *l, const struct linux_sys_stat64_args *uap, register_t *retval) |
151 | { |
152 | /* { |
153 | syscallarg(const char *) path; |
154 | syscallarg(struct linux_stat64 *) sp; |
155 | } */ |
156 | |
157 | return linux_do_stat64(l, uap, retval, FOLLOW); |
158 | } |
159 | |
160 | int |
161 | linux_sys_lstat64(struct lwp *l, const struct linux_sys_lstat64_args *uap, register_t *retval) |
162 | { |
163 | /* { |
164 | syscallarg(const char *) path; |
165 | syscallarg(struct linux_stat64 *) sp; |
166 | } */ |
167 | |
168 | return linux_do_stat64(l, (const void *)uap, retval, NOFOLLOW); |
169 | } |
170 | |
171 | int |
172 | linux_sys_fstatat64(struct lwp *l, const struct linux_sys_fstatat64_args *uap, register_t *retval) |
173 | { |
174 | /* { |
175 | syscallarg(int) fd; |
176 | syscallarg(const char *) path; |
177 | syscallarg(struct linux_stat64 *) sp; |
178 | syscallarg(int) flag; |
179 | } */ |
180 | struct linux_stat64 tmplst; |
181 | struct stat tmpst; |
182 | int error, nd_flag; |
183 | |
184 | if (SCARG(uap, flag) & LINUX_AT_SYMLINK_NOFOLLOW) |
185 | nd_flag = NOFOLLOW; |
186 | else |
187 | nd_flag = FOLLOW; |
188 | |
189 | error = do_sys_statat(l, SCARG(uap, fd), SCARG(uap, path), nd_flag, &tmpst); |
190 | if (error != 0) |
191 | return error; |
192 | |
193 | bsd_to_linux_stat(&tmpst, &tmplst); |
194 | |
195 | return copyout(&tmplst, SCARG(uap, sp), sizeof tmplst); |
196 | } |
197 | |
198 | #ifndef __alpha__ |
199 | int |
200 | linux_sys_truncate64(struct lwp *l, const struct linux_sys_truncate64_args *uap, register_t *retval) |
201 | { |
202 | /* { |
203 | syscallarg(const char *) path; |
204 | syscallarg(off_t) length; |
205 | } */ |
206 | struct sys_truncate_args ta; |
207 | |
208 | /* Linux doesn't have the 'pad' pseudo-parameter */ |
209 | SCARG(&ta, path) = SCARG(uap, path); |
210 | SCARG(&ta, PAD) = 0; |
211 | SCARG(&ta, length) = SCARG(uap, length); |
212 | |
213 | return sys_truncate(l, &ta, retval); |
214 | } |
215 | |
216 | int |
217 | linux_sys_ftruncate64(struct lwp *l, const struct linux_sys_ftruncate64_args *uap, register_t *retval) |
218 | { |
219 | /* { |
220 | syscallarg(unsigned int) fd; |
221 | syscallarg(off_t) length; |
222 | } */ |
223 | struct sys_ftruncate_args ta; |
224 | |
225 | /* Linux doesn't have the 'pad' pseudo-parameter */ |
226 | SCARG(&ta, fd) = SCARG(uap, fd); |
227 | SCARG(&ta, PAD) = 0; |
228 | SCARG(&ta, length) = SCARG(uap, length); |
229 | |
230 | return sys_ftruncate(l, &ta, retval); |
231 | } |
232 | #endif /* __alpha__ */ |
233 | |
234 | /* |
235 | * Linux 'readdir' call. This code is mostly taken from the |
236 | * SunOS getdents call (see compat/sunos/sunos_misc.c), though |
237 | * an attempt has been made to keep it a little cleaner. |
238 | * |
239 | * The d_off field contains the offset of the next valid entry, |
240 | * unless the older Linux getdents(2), which used to have it set |
241 | * to the offset of the entry itself. This function also doesn't |
242 | * need to deal with the old count == 1 glibc problem. |
243 | * |
244 | * Read in BSD-style entries, convert them, and copy them out. |
245 | * |
246 | * Note that this doesn't handle union-mounted filesystems. |
247 | */ |
248 | int |
249 | linux_sys_getdents64(struct lwp *l, const struct linux_sys_getdents64_args *uap, register_t *retval) |
250 | { |
251 | /* { |
252 | syscallarg(int) fd; |
253 | syscallarg(struct linux_dirent64 *) dent; |
254 | syscallarg(unsigned int) count; |
255 | } */ |
256 | struct dirent *bdp; |
257 | struct vnode *vp; |
258 | char *inp, *tbuf; /* BSD-format */ |
259 | int len, reclen; /* BSD-format */ |
260 | char *outp; /* Linux-format */ |
261 | int resid, linux_reclen = 0; /* Linux-format */ |
262 | file_t *fp; |
263 | struct uio auio; |
264 | struct iovec aiov; |
265 | struct linux_dirent64 idb; |
266 | off_t off; /* true file offset */ |
267 | int buflen, error, eofflag, nbytes; |
268 | struct vattr va; |
269 | off_t *cookiebuf = NULL, *cookie; |
270 | int ncookies; |
271 | |
272 | /* fd_getvnode() will use the descriptor for us */ |
273 | if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0) |
274 | return (error); |
275 | |
276 | if ((fp->f_flag & FREAD) == 0) { |
277 | error = EBADF; |
278 | goto out1; |
279 | } |
280 | |
281 | vp = (struct vnode *)fp->f_data; |
282 | if (vp->v_type != VDIR) { |
283 | error = ENOTDIR; |
284 | goto out1; |
285 | } |
286 | |
287 | vn_lock(vp, LK_SHARED | LK_RETRY); |
288 | error = VOP_GETATTR(vp, &va, l->l_cred); |
289 | VOP_UNLOCK(vp); |
290 | if (error) |
291 | goto out1; |
292 | |
293 | nbytes = SCARG(uap, count); |
294 | buflen = min(MAXBSIZE, nbytes); |
295 | if (buflen < va.va_blocksize) |
296 | buflen = va.va_blocksize; |
297 | tbuf = malloc(buflen, M_TEMP, M_WAITOK); |
298 | |
299 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
300 | off = fp->f_offset; |
301 | again: |
302 | aiov.iov_base = tbuf; |
303 | aiov.iov_len = buflen; |
304 | auio.uio_iov = &aiov; |
305 | auio.uio_iovcnt = 1; |
306 | auio.uio_rw = UIO_READ; |
307 | auio.uio_resid = buflen; |
308 | auio.uio_offset = off; |
309 | UIO_SETUP_SYSSPACE(&auio); |
310 | /* |
311 | * First we read into the malloc'ed buffer, then |
312 | * we massage it into user space, one record at a time. |
313 | */ |
314 | error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf, |
315 | &ncookies); |
316 | if (error) |
317 | goto out; |
318 | |
319 | inp = tbuf; |
320 | outp = (void *)SCARG(uap, dent); |
321 | resid = nbytes; |
322 | if ((len = buflen - auio.uio_resid) == 0) |
323 | goto eof; |
324 | |
325 | for (cookie = cookiebuf; len > 0; len -= reclen) { |
326 | bdp = (struct dirent *)inp; |
327 | reclen = bdp->d_reclen; |
328 | if (reclen & 3) |
329 | panic("linux_readdir" ); |
330 | if (bdp->d_fileno == 0) { |
331 | inp += reclen; /* it is a hole; squish it out */ |
332 | if (cookie) |
333 | off = *cookie++; |
334 | else |
335 | off += reclen; |
336 | continue; |
337 | } |
338 | linux_reclen = LINUX_RECLEN(&idb, bdp->d_namlen); |
339 | if (reclen > len || resid < linux_reclen) { |
340 | /* entry too big for buffer, so just stop */ |
341 | outp++; |
342 | break; |
343 | } |
344 | if (cookie) |
345 | off = *cookie++; /* each entry points to next */ |
346 | else |
347 | off += reclen; |
348 | /* |
349 | * Massage in place to make a Linux-shaped dirent (otherwise |
350 | * we have to worry about touching user memory outside of |
351 | * the copyout() call). |
352 | */ |
353 | idb.d_ino = bdp->d_fileno; |
354 | idb.d_type = bdp->d_type; |
355 | idb.d_off = off; |
356 | idb.d_reclen = (u_short)linux_reclen; |
357 | strcpy(idb.d_name, bdp->d_name); |
358 | if ((error = copyout((void *)&idb, outp, linux_reclen))) |
359 | goto out; |
360 | /* advance past this real entry */ |
361 | inp += reclen; |
362 | /* advance output past Linux-shaped entry */ |
363 | outp += linux_reclen; |
364 | resid -= linux_reclen; |
365 | } |
366 | |
367 | /* if we squished out the whole block, try again */ |
368 | if (outp == (void *)SCARG(uap, dent)) { |
369 | if (cookiebuf) |
370 | free(cookiebuf, M_TEMP); |
371 | cookiebuf = NULL; |
372 | goto again; |
373 | } |
374 | fp->f_offset = off; /* update the vnode offset */ |
375 | |
376 | eof: |
377 | *retval = nbytes - resid; |
378 | out: |
379 | VOP_UNLOCK(vp); |
380 | if (cookiebuf) |
381 | free(cookiebuf, M_TEMP); |
382 | free(tbuf, M_TEMP); |
383 | out1: |
384 | fd_putfile(SCARG(uap, fd)); |
385 | return error; |
386 | } |
387 | |