Commit | Line | Data |
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da7c5cc6 | 1 | /* |
eb668bc6 KM |
2 | * Copyright (c) 1982, 1986, 1989 Regents of the University of California. |
3 | * All rights reserved. | |
da7c5cc6 | 4 | * |
eb668bc6 KM |
5 | * Redistribution and use in source and binary forms are permitted |
6 | * provided that the above copyright notice and this paragraph are | |
7 | * duplicated in all such forms and that any documentation, | |
8 | * advertising materials, and other materials related to such | |
9 | * distribution and use acknowledge that the software was developed | |
10 | * by the University of California, Berkeley. The name of the | |
11 | * University may not be used to endorse or promote products derived | |
12 | * from this software without specific prior written permission. | |
13 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR | |
14 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED | |
15 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. | |
16 | * | |
366f2ef0 | 17 | * @(#)vfs_vnops.c 7.9 (Berkeley) %G% |
da7c5cc6 | 18 | */ |
961945a8 | 19 | |
94368568 JB |
20 | #include "param.h" |
21 | #include "systm.h" | |
94368568 | 22 | #include "user.h" |
eb668bc6 | 23 | #include "kernel.h" |
94368568 | 24 | #include "file.h" |
eb668bc6 KM |
25 | #include "stat.h" |
26 | #include "buf.h" | |
27 | #include "proc.h" | |
28 | #include "uio.h" | |
94368568 JB |
29 | #include "socket.h" |
30 | #include "socketvar.h" | |
eb668bc6 KM |
31 | #include "mount.h" |
32 | #include "vnode.h" | |
33 | #include "../ufs/inode.h" | |
34 | #include "../ufs/fs.h" | |
35 | #include "../ufs/quota.h" | |
36 | #include "ioctl.h" | |
37 | #include "tty.h" | |
fc96c615 | 38 | |
eb668bc6 KM |
39 | int vn_read(), vn_write(), vn_ioctl(), vn_select(), vn_close(); |
40 | struct fileops vnops = | |
41 | { vn_read, vn_write, vn_ioctl, vn_select, vn_close }; | |
d301d150 | 42 | |
fc96c615 | 43 | /* |
eb668bc6 KM |
44 | * Common code for vnode open operations. |
45 | * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. | |
fc96c615 | 46 | */ |
eb668bc6 KM |
47 | vn_open(ndp, fmode, cmode) |
48 | register struct nameidata *ndp; | |
49 | int fmode, cmode; | |
50 | { | |
51 | register struct vnode *vp; | |
52 | struct vattr vat; | |
53 | struct vattr *vap = &vat; | |
54 | int error; | |
55 | ||
56 | if (fmode & FCREAT) { | |
57 | ndp->ni_nameiop = CREATE | LOCKPARENT | LOCKLEAF; | |
58 | if ((fmode & FEXCL) == 0) | |
59 | ndp->ni_nameiop |= FOLLOW; | |
60 | if (error = namei(ndp)) | |
61 | return (error); | |
62 | if (ndp->ni_vp == NULL) { | |
63 | vattr_null(vap); | |
64 | vap->va_type = VREG; | |
65 | vap->va_mode = cmode; | |
66 | if (error = VOP_CREATE(ndp, vap)) | |
67 | return (error); | |
68 | fmode &= ~FTRUNC; | |
69 | vp = ndp->ni_vp; | |
70 | } else { | |
71 | vp = ndp->ni_vp; | |
72 | ndp->ni_vp = 0; | |
73 | VOP_ABORTOP(ndp); | |
74 | ndp->ni_vp = vp; | |
75 | if (fmode & FEXCL) { | |
76 | error = EEXIST; | |
77 | goto bad; | |
78 | } | |
79 | fmode &= ~FCREAT; | |
80 | } | |
81 | } else { | |
82 | ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF; | |
83 | if (error = namei(ndp)) | |
84 | return (error); | |
85 | vp = ndp->ni_vp; | |
86 | } | |
87 | if (vp->v_type == VSOCK) { | |
88 | error = EOPNOTSUPP; | |
89 | goto bad; | |
90 | } | |
91 | if ((fmode & FCREAT) == 0) { | |
92 | if (fmode & FREAD) { | |
cd811e9a | 93 | if (error = VOP_ACCESS(vp, VREAD, ndp->ni_cred)) |
eb668bc6 KM |
94 | goto bad; |
95 | } | |
96 | if (fmode & (FWRITE|FTRUNC)) { | |
eb668bc6 KM |
97 | if (vp->v_type == VDIR) { |
98 | error = EISDIR; | |
99 | goto bad; | |
100 | } | |
cd811e9a KM |
101 | if ((error = vn_writechk(vp)) || |
102 | (error = VOP_ACCESS(vp, VWRITE, ndp->ni_cred))) | |
103 | goto bad; | |
eb668bc6 KM |
104 | } |
105 | } | |
106 | if (fmode & FTRUNC) { | |
107 | vattr_null(vap); | |
108 | vap->va_size = 0; | |
109 | if (error = VOP_SETATTR(vp, vap, ndp->ni_cred)) | |
110 | goto bad; | |
111 | } | |
112 | VOP_UNLOCK(vp); | |
113 | if (setjmp(&u.u_qsave)) { | |
114 | if (error == 0) | |
115 | error = EINTR; | |
116 | return (error); | |
117 | } | |
d099f49b KM |
118 | error = VOP_OPEN(vp, fmode, ndp->ni_cred); |
119 | if (error) | |
120 | vrele(vp); | |
121 | return (error); | |
eb668bc6 KM |
122 | |
123 | bad: | |
124 | vput(vp); | |
125 | return(error); | |
126 | } | |
127 | ||
128 | /* | |
cd811e9a KM |
129 | * Check for write permissions on the specified vnode. |
130 | * The read-only status of the file system is checked. | |
131 | * Also, prototype text segments cannot be written. | |
eb668bc6 | 132 | */ |
cd811e9a | 133 | vn_writechk(vp) |
eb668bc6 | 134 | register struct vnode *vp; |
fc96c615 | 135 | { |
fc96c615 | 136 | |
cd811e9a KM |
137 | /* |
138 | * Disallow write attempts on read-only file systems; | |
139 | * unless the file is a socket or a block or character | |
140 | * device resident on the file system. | |
141 | */ | |
142 | if ((vp->v_mount->m_flag & M_RDONLY) && vp->v_type != VCHR && | |
143 | vp->v_type != VBLK && vp->v_type != VSOCK) | |
144 | return (EROFS); | |
145 | /* | |
146 | * If there's shared text associated with | |
147 | * the vnode, try to free it up once. If | |
148 | * we fail, we can't allow writing. | |
149 | */ | |
150 | if (vp->v_flag & VTEXT) | |
151 | xrele(vp); | |
152 | if (vp->v_flag & VTEXT) | |
153 | return (ETXTBSY); | |
154 | return (0); | |
eb668bc6 KM |
155 | } |
156 | ||
157 | /* | |
158 | * Vnode version of rdwri() for calls on file systems. | |
159 | */ | |
160 | vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid) | |
161 | enum uio_rw rw; | |
162 | struct vnode *vp; | |
163 | caddr_t base; | |
164 | int len; | |
165 | off_t offset; | |
166 | enum uio_seg segflg; | |
167 | int ioflg; | |
168 | struct ucred *cred; | |
169 | int *aresid; | |
170 | { | |
171 | struct uio auio; | |
172 | struct iovec aiov; | |
173 | int error; | |
174 | ||
175 | auio.uio_iov = &aiov; | |
176 | auio.uio_iovcnt = 1; | |
177 | aiov.iov_base = base; | |
178 | aiov.iov_len = len; | |
179 | auio.uio_resid = len; | |
180 | auio.uio_offset = offset; | |
181 | auio.uio_segflg = segflg; | |
182 | auio.uio_rw = rw; | |
183 | if (rw == UIO_READ) | |
184 | error = VOP_READ(vp, &auio, &offset, ioflg, cred); | |
185 | else | |
186 | error = VOP_WRITE(vp, &auio, &offset, ioflg, cred); | |
187 | if (aresid) | |
188 | *aresid = auio.uio_resid; | |
189 | else | |
190 | if (auio.uio_resid && error == 0) | |
191 | error = EIO; | |
192 | return (error); | |
193 | } | |
194 | ||
195 | vn_read(fp, uio, cred) | |
196 | struct file *fp; | |
197 | struct uio *uio; | |
198 | struct ucred *cred; | |
199 | { | |
200 | ||
201 | return (VOP_READ((struct vnode *)fp->f_data, uio, &(fp->f_offset), | |
202 | (fp->f_flag & FNDELAY) ? IO_NDELAY : 0, cred)); | |
203 | } | |
204 | ||
205 | vn_write(fp, uio, cred) | |
206 | struct file *fp; | |
207 | struct uio *uio; | |
208 | struct ucred *cred; | |
209 | { | |
210 | register struct vnode *vp = (struct vnode *)fp->f_data; | |
211 | int ioflag = 0; | |
212 | ||
213 | if (vp->v_type == VREG && (fp->f_flag & FAPPEND)) | |
214 | ioflag |= IO_APPEND; | |
215 | if (fp->f_flag & FNDELAY) | |
216 | ioflag |= IO_NDELAY; | |
217 | return (VOP_WRITE(vp, uio, &(fp->f_offset), ioflag, cred)); | |
218 | } | |
219 | ||
220 | /* | |
221 | * Get stat info for a vnode. | |
222 | */ | |
223 | vn_stat(vp, sb) | |
224 | struct vnode *vp; | |
225 | register struct stat *sb; | |
226 | { | |
227 | struct vattr vattr; | |
228 | register struct vattr *vap; | |
229 | int error; | |
230 | u_short mode; | |
231 | ||
232 | vap = &vattr; | |
233 | error = VOP_GETATTR(vp, vap, u.u_cred); | |
234 | if (error) | |
235 | return (error); | |
236 | /* | |
237 | * Copy from vattr table | |
238 | */ | |
239 | sb->st_dev = vap->va_fsid; | |
240 | sb->st_ino = vap->va_fileid; | |
241 | mode = vap->va_mode; | |
242 | switch (vp->v_type) { | |
243 | case VREG: | |
244 | mode |= IFREG; | |
245 | break; | |
246 | case VDIR: | |
247 | mode |= IFDIR; | |
248 | break; | |
249 | case VBLK: | |
250 | mode |= IFBLK; | |
251 | break; | |
252 | case VCHR: | |
253 | mode |= IFCHR; | |
254 | break; | |
255 | case VLNK: | |
256 | mode |= IFLNK; | |
257 | break; | |
258 | case VSOCK: | |
259 | mode |= IFSOCK; | |
260 | break; | |
261 | default: | |
262 | return (EBADF); | |
263 | }; | |
264 | sb->st_mode = mode; | |
265 | sb->st_nlink = vap->va_nlink; | |
266 | sb->st_uid = vap->va_uid; | |
267 | sb->st_gid = vap->va_gid; | |
268 | sb->st_rdev = vap->va_rdev; | |
269 | sb->st_size = vap->va_size; | |
270 | sb->st_atime = vap->va_atime.tv_sec; | |
271 | sb->st_spare1 = 0; | |
272 | sb->st_mtime = vap->va_mtime.tv_sec; | |
273 | sb->st_spare2 = 0; | |
274 | sb->st_ctime = vap->va_ctime.tv_sec; | |
275 | sb->st_spare3 = 0; | |
276 | sb->st_blksize = vap->va_blocksize; | |
2ff0b8da KM |
277 | sb->st_flags = vap->va_flags; |
278 | sb->st_gen = vap->va_gen; | |
366f2ef0 | 279 | sb->st_blocks = vap->va_bytes / S_BLKSIZE; |
eb668bc6 KM |
280 | return (0); |
281 | } | |
282 | ||
283 | /* | |
284 | * Vnode ioctl call | |
285 | */ | |
286 | vn_ioctl(fp, com, data) | |
287 | struct file *fp; | |
288 | int com; | |
289 | caddr_t data; | |
290 | { | |
291 | register struct vnode *vp = ((struct vnode *)fp->f_data); | |
292 | struct vattr vattr; | |
293 | int error; | |
294 | ||
295 | switch (vp->v_type) { | |
296 | ||
297 | case VREG: | |
298 | case VDIR: | |
299 | if (com == FIONREAD) { | |
300 | if (error = VOP_GETATTR(vp, &vattr, u.u_cred)) | |
301 | return (error); | |
302 | *(off_t *)data = vattr.va_size - fp->f_offset; | |
303 | return (0); | |
304 | } | |
305 | if (com == FIONBIO || com == FIOASYNC) /* XXX */ | |
306 | return (0); /* XXX */ | |
307 | /* fall into ... */ | |
308 | ||
309 | default: | |
310 | return (ENOTTY); | |
311 | ||
312 | case VCHR: | |
313 | case VBLK: | |
314 | u.u_r.r_val1 = 0; | |
315 | if (setjmp(&u.u_qsave)) { | |
316 | if ((u.u_sigintr & sigmask(u.u_procp->p_cursig)) != 0) | |
317 | return(EINTR); | |
318 | u.u_eosys = RESTARTSYS; | |
319 | return (0); | |
fc96c615 | 320 | } |
eb668bc6 | 321 | return (VOP_IOCTL(vp, com, data, fp->f_flag, u.u_cred)); |
fc96c615 | 322 | } |
eb668bc6 KM |
323 | } |
324 | ||
325 | /* | |
326 | * Vnode select call | |
327 | */ | |
328 | vn_select(fp, which) | |
329 | struct file *fp; | |
330 | int which; | |
331 | { | |
332 | return(VOP_SELECT(((struct vnode *)fp->f_data), which, u.u_cred)); | |
333 | } | |
334 | ||
335 | /* | |
336 | * Vnode close call | |
337 | */ | |
338 | vn_close(fp) | |
339 | register struct file *fp; | |
340 | { | |
341 | struct vnode *vp = ((struct vnode *)fp->f_data); | |
342 | int error; | |
343 | ||
344 | if (fp->f_flag & (FSHLOCK|FEXLOCK)) | |
345 | vn_unlock(fp, FSHLOCK|FEXLOCK); | |
40123f2c | 346 | /* |
eb668bc6 KM |
347 | * Must delete vnode reference from this file entry |
348 | * before VOP_CLOSE, so that only other references | |
349 | * will prevent close. | |
40123f2c | 350 | */ |
eb668bc6 KM |
351 | fp->f_data = (caddr_t) 0; |
352 | error = VOP_CLOSE(vp, fp->f_flag, u.u_cred); | |
353 | vrele(vp); | |
354 | return (error); | |
355 | } | |
356 | ||
357 | /* | |
358 | * Place an advisory lock on a vnode. | |
359 | * !! THIS IMPLIES THAT ALL STATEFUL FILE SERVERS WILL USE file table entries | |
360 | */ | |
361 | vn_lock(fp, cmd) | |
362 | register struct file *fp; | |
363 | int cmd; | |
364 | { | |
365 | register int priority = PLOCK; | |
366 | register struct vnode *vp = (struct vnode *)fp->f_data; | |
367 | ||
368 | if ((cmd & LOCK_EX) == 0) | |
369 | priority += 4; | |
370 | if (setjmp(&u.u_qsave)) { | |
371 | if ((u.u_sigintr & sigmask(u.u_procp->p_cursig)) != 0) | |
372 | return(EINTR); | |
373 | u.u_eosys = RESTARTSYS; | |
fdd90ee3 | 374 | return (0); |
eb668bc6 | 375 | } |
40123f2c | 376 | /* |
eb668bc6 KM |
377 | * If there's a exclusive lock currently applied |
378 | * to the file, then we've gotta wait for the | |
379 | * lock with everyone else. | |
40123f2c | 380 | */ |
eb668bc6 KM |
381 | again: |
382 | while (vp->v_flag & VEXLOCK) { | |
383 | /* | |
384 | * If we're holding an exclusive | |
385 | * lock, then release it. | |
386 | */ | |
387 | if (fp->f_flag & FEXLOCK) { | |
388 | vn_unlock(fp, FEXLOCK); | |
389 | continue; | |
390 | } | |
391 | if (cmd & LOCK_NB) | |
392 | return (EWOULDBLOCK); | |
393 | vp->v_flag |= VLWAIT; | |
394 | sleep((caddr_t)&vp->v_exlockc, priority); | |
fc96c615 | 395 | } |
eb668bc6 KM |
396 | if ((cmd & LOCK_EX) && (vp->v_flag & VSHLOCK)) { |
397 | /* | |
398 | * Must wait for any shared locks to finish | |
399 | * before we try to apply a exclusive lock. | |
400 | * | |
401 | * If we're holding a shared | |
402 | * lock, then release it. | |
403 | */ | |
404 | if (fp->f_flag & FSHLOCK) { | |
405 | vn_unlock(fp, FSHLOCK); | |
406 | goto again; | |
407 | } | |
408 | if (cmd & LOCK_NB) | |
409 | return (EWOULDBLOCK); | |
410 | vp->v_flag |= VLWAIT; | |
411 | sleep((caddr_t)&vp->v_shlockc, PLOCK); | |
412 | goto again; | |
413 | } | |
414 | if (fp->f_flag & FEXLOCK) | |
415 | panic("vn_lock"); | |
416 | if (cmd & LOCK_EX) { | |
417 | cmd &= ~LOCK_SH; | |
418 | vp->v_exlockc++; | |
419 | vp->v_flag |= VEXLOCK; | |
420 | fp->f_flag |= FEXLOCK; | |
421 | } | |
422 | if ((cmd & LOCK_SH) && (fp->f_flag & FSHLOCK) == 0) { | |
423 | vp->v_shlockc++; | |
424 | vp->v_flag |= VSHLOCK; | |
425 | fp->f_flag |= FSHLOCK; | |
849cbd39 | 426 | } |
eb668bc6 | 427 | return (0); |
fc96c615 BJ |
428 | } |
429 | ||
430 | /* | |
eb668bc6 | 431 | * Unlock a file. |
fc96c615 | 432 | */ |
eb668bc6 KM |
433 | vn_unlock(fp, kind) |
434 | register struct file *fp; | |
435 | int kind; | |
fc96c615 | 436 | { |
eb668bc6 KM |
437 | register struct vnode *vp = (struct vnode *)fp->f_data; |
438 | int flags; | |
fc96c615 | 439 | |
eb668bc6 KM |
440 | kind &= fp->f_flag; |
441 | if (vp == NULL || kind == 0) | |
442 | return; | |
443 | flags = vp->v_flag; | |
444 | if (kind & FSHLOCK) { | |
445 | if ((flags & VSHLOCK) == 0) | |
446 | panic("vn_unlock: SHLOCK"); | |
447 | if (--vp->v_shlockc == 0) { | |
448 | vp->v_flag &= ~VSHLOCK; | |
449 | if (flags & VLWAIT) | |
450 | wakeup((caddr_t)&vp->v_shlockc); | |
451 | } | |
452 | fp->f_flag &= ~FSHLOCK; | |
453 | } | |
454 | if (kind & FEXLOCK) { | |
455 | if ((flags & VEXLOCK) == 0) | |
456 | panic("vn_unlock: EXLOCK"); | |
457 | if (--vp->v_exlockc == 0) { | |
458 | vp->v_flag &= ~(VEXLOCK|VLWAIT); | |
459 | if (flags & VLWAIT) | |
460 | wakeup((caddr_t)&vp->v_exlockc); | |
461 | } | |
462 | fp->f_flag &= ~FEXLOCK; | |
fc96c615 | 463 | } |
eb668bc6 KM |
464 | } |
465 | ||
466 | /* | |
467 | * vn_fhtovp() - convert a fh to a vnode ptr (optionally locked) | |
468 | * - look up fsid in mount list (if not found ret error) | |
469 | * - get vp by calling VFS_FHTOVP() macro | |
470 | * - if lockflag lock it with VOP_LOCK() | |
471 | */ | |
472 | vn_fhtovp(fhp, lockflag, vpp) | |
473 | fhandle_t *fhp; | |
474 | int lockflag; | |
475 | struct vnode **vpp; | |
476 | { | |
477 | register struct mount *mp; | |
478 | int error; | |
479 | ||
480 | if ((mp = getvfs(&fhp->fh_fsid)) == NULL) | |
481 | return (ESTALE); | |
a2f658f9 KM |
482 | if (VFS_FHTOVP(mp, &fhp->fh_fid, vpp)) |
483 | return (ESTALE); | |
484 | if (!lockflag) | |
485 | VOP_UNLOCK(*vpp); | |
eb668bc6 KM |
486 | return (0); |
487 | } | |
488 | ||
489 | /* | |
490 | * Revoke access the current tty by all processes. | |
491 | * Used only by the super-user in init | |
492 | * to give ``clean'' terminals at login. | |
493 | */ | |
494 | vhangup() | |
495 | { | |
496 | ||
497 | if (u.u_error = suser(u.u_cred, &u.u_acflag)) | |
498 | return; | |
499 | if (u.u_ttyp == NULL) | |
500 | return; | |
501 | forceclose(u.u_ttyd); | |
502 | if ((u.u_ttyp->t_state) & TS_ISOPEN) | |
503 | gsignal(u.u_ttyp->t_pgid, SIGHUP); | |
504 | u.u_ttyp->t_session = 0; | |
505 | u.u_ttyp->t_pgid = 0; | |
506 | } | |
507 | ||
508 | forceclose(dev) | |
509 | dev_t dev; | |
510 | { | |
511 | register struct file *fp; | |
512 | register struct vnode *vp; | |
513 | ||
514 | for (fp = file; fp < fileNFILE; fp++) { | |
515 | if (fp->f_count == 0) | |
516 | continue; | |
517 | if (fp->f_type != DTYPE_VNODE) | |
518 | continue; | |
519 | vp = (struct vnode *)fp->f_data; | |
520 | if (vp == 0) | |
521 | continue; | |
522 | if (vp->v_type != VCHR) | |
523 | continue; | |
524 | if (vp->v_rdev != dev) | |
525 | continue; | |
526 | fp->f_flag &= ~(FREAD|FWRITE); | |
527 | } | |
528 | } | |
529 | ||
d099f49b KM |
530 | /* |
531 | * Vnode reference, just increment the count | |
532 | */ | |
533 | void vref(vp) | |
534 | struct vnode *vp; | |
535 | { | |
536 | ||
537 | vp->v_count++; | |
538 | } | |
539 | ||
eb668bc6 KM |
540 | /* |
541 | * Vnode release, just decrement the count and call VOP_INACTIVE() | |
542 | */ | |
543 | void vrele(vp) | |
544 | register struct vnode *vp; | |
545 | { | |
546 | ||
547 | if (vp == NULL) | |
548 | return; | |
549 | vp->v_count--; | |
550 | if (vp->v_count < 0) | |
551 | printf("inode %d, bad ref count %d\n", | |
552 | VTOI(vp)->i_number, vp->v_count); | |
553 | if (vp->v_count == 0) | |
554 | VOP_INACTIVE(vp); | |
555 | } | |
556 | ||
557 | /* | |
558 | * vput(), just unlock and vrele() | |
559 | */ | |
560 | vput(vp) | |
561 | register struct vnode *vp; | |
562 | { | |
563 | VOP_UNLOCK(vp); | |
564 | vrele(vp); | |
565 | } | |
566 | ||
567 | /* | |
568 | * Noop | |
569 | */ | |
570 | vfs_noop() | |
571 | { | |
572 | ||
573 | return (ENXIO); | |
574 | } | |
575 | ||
576 | /* | |
577 | * Null op | |
578 | */ | |
579 | vfs_nullop() | |
580 | { | |
581 | ||
582 | return (0); | |
fc96c615 | 583 | } |