1 /*-
2 * modified for EXT2FS support in Lites 1.1
3 *
4 * Aug 1995, Godmar Back (gback@cs.utah.edu)
5 * University of Utah, Department of Computer Science
6 */
7 /*-
8 * Copyright (c) 1982, 1986, 1989, 1993
9 * The Regents of the University of California. All rights reserved.
10 * (c) UNIX System Laboratories, Inc.
11 * All or some portions of this file are derived from material licensed
12 * to the University of California by American Telephone and Telegraph
13 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
14 * the permission of UNIX System Laboratories, Inc.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 * @(#)ufs_vnops.c 8.7 (Berkeley) 2/3/94
41 * @(#)ufs_vnops.c 8.27 (Berkeley) 5/27/95
42 * $FreeBSD: releng/10.3/sys/fs/ext2fs/ext2_vnops.c 295714 2016-02-17 19:09:06Z pfg $
43 */
44
45 #include "opt_suiddir.h"
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/kernel.h>
50 #include <sys/fcntl.h>
51 #include <sys/filio.h>
52 #include <sys/stat.h>
53 #include <sys/bio.h>
54 #include <sys/buf.h>
55 #include <sys/endian.h>
56 #include <sys/priv.h>
57 #include <sys/rwlock.h>
58 #include <sys/mount.h>
59 #include <sys/unistd.h>
60 #include <sys/time.h>
61 #include <sys/vnode.h>
62 #include <sys/namei.h>
63 #include <sys/lockf.h>
64 #include <sys/event.h>
65 #include <sys/conf.h>
66 #include <sys/file.h>
67
68 #include <vm/vm.h>
69 #include <vm/vm_param.h>
70 #include <vm/vm_extern.h>
71 #include <vm/vm_object.h>
72 #include <vm/vm_page.h>
73 #include <vm/vm_pager.h>
74 #include <vm/vnode_pager.h>
75
76 #include "opt_directio.h"
77
78 #include <ufs/ufs/dir.h>
79
80 #include <fs/ext2fs/fs.h>
81 #include <fs/ext2fs/inode.h>
82 #include <fs/ext2fs/ext2_extern.h>
83 #include <fs/ext2fs/ext2fs.h>
84 #include <fs/ext2fs/ext2_dinode.h>
85 #include <fs/ext2fs/ext2_dir.h>
86 #include <fs/ext2fs/ext2_mount.h>
87
88 static int ext2_makeinode(int mode, struct vnode *, struct vnode **, struct componentname *);
89 static void ext2_itimes_locked(struct vnode *);
90 static int ext4_ext_read(struct vop_read_args *);
91 static int ext2_ind_read(struct vop_read_args *);
92
93 static vop_access_t ext2_access;
94 static int ext2_chmod(struct vnode *, int, struct ucred *, struct thread *);
95 static int ext2_chown(struct vnode *, uid_t, gid_t, struct ucred *,
96 struct thread *);
97 static vop_close_t ext2_close;
98 static vop_create_t ext2_create;
99 static vop_fsync_t ext2_fsync;
100 static vop_getpages_t ext2_getpages;
101 static vop_getattr_t ext2_getattr;
102 static vop_ioctl_t ext2_ioctl;
103 static vop_link_t ext2_link;
104 static vop_mkdir_t ext2_mkdir;
105 static vop_mknod_t ext2_mknod;
106 static vop_open_t ext2_open;
107 static vop_pathconf_t ext2_pathconf;
108 static vop_print_t ext2_print;
109 static vop_read_t ext2_read;
110 static vop_readlink_t ext2_readlink;
111 static vop_remove_t ext2_remove;
112 static vop_rename_t ext2_rename;
113 static vop_rmdir_t ext2_rmdir;
114 static vop_setattr_t ext2_setattr;
115 static vop_strategy_t ext2_strategy;
116 static vop_symlink_t ext2_symlink;
117 static vop_write_t ext2_write;
118 static vop_vptofh_t ext2_vptofh;
119 static vop_close_t ext2fifo_close;
120 static vop_kqfilter_t ext2fifo_kqfilter;
121
122 /* Global vfs data structures for ext2. */
123 struct vop_vector ext2_vnodeops = {
124 .vop_default = &default_vnodeops,
125 .vop_access = ext2_access,
126 .vop_bmap = ext2_bmap,
127 .vop_cachedlookup = ext2_lookup,
128 .vop_close = ext2_close,
129 .vop_create = ext2_create,
130 .vop_fsync = ext2_fsync,
131 .vop_getpages = ext2_getpages,
132 .vop_getattr = ext2_getattr,
133 .vop_inactive = ext2_inactive,
134 .vop_ioctl = ext2_ioctl,
135 .vop_link = ext2_link,
136 .vop_lookup = vfs_cache_lookup,
137 .vop_mkdir = ext2_mkdir,
138 .vop_mknod = ext2_mknod,
139 .vop_open = ext2_open,
140 .vop_pathconf = ext2_pathconf,
141 .vop_poll = vop_stdpoll,
142 .vop_print = ext2_print,
143 .vop_read = ext2_read,
144 .vop_readdir = ext2_readdir,
145 .vop_readlink = ext2_readlink,
146 .vop_reallocblks = ext2_reallocblks,
147 .vop_reclaim = ext2_reclaim,
148 .vop_remove = ext2_remove,
149 .vop_rename = ext2_rename,
150 .vop_rmdir = ext2_rmdir,
151 .vop_setattr = ext2_setattr,
152 .vop_strategy = ext2_strategy,
153 .vop_symlink = ext2_symlink,
154 .vop_write = ext2_write,
155 .vop_vptofh = ext2_vptofh,
156 };
157
158 struct vop_vector ext2_fifoops = {
159 .vop_default = &fifo_specops,
160 .vop_access = ext2_access,
161 .vop_close = ext2fifo_close,
162 .vop_fsync = ext2_fsync,
163 .vop_getattr = ext2_getattr,
164 .vop_inactive = ext2_inactive,
165 .vop_kqfilter = ext2fifo_kqfilter,
166 .vop_print = ext2_print,
167 .vop_read = VOP_PANIC,
168 .vop_reclaim = ext2_reclaim,
169 .vop_setattr = ext2_setattr,
170 .vop_write = VOP_PANIC,
171 .vop_vptofh = ext2_vptofh,
172 };
173
174 /*
175 * A virgin directory (no blushing please).
176 * Note that the type and namlen fields are reversed relative to ext2.
177 * Also, we don't use `struct odirtemplate', since it would just cause
178 * endianness problems.
179 */
180 static struct dirtemplate mastertemplate = {
181 0, 12, 1, EXT2_FT_DIR, ".",
182 0, DIRBLKSIZ - 12, 2, EXT2_FT_DIR, ".."
183 };
184 static struct dirtemplate omastertemplate = {
185 0, 12, 1, EXT2_FT_UNKNOWN, ".",
186 0, DIRBLKSIZ - 12, 2, EXT2_FT_UNKNOWN, ".."
187 };
188
189 static void
190 ext2_itimes_locked(struct vnode *vp)
191 {
192 struct inode *ip;
193 struct timespec ts;
194
195 ASSERT_VI_LOCKED(vp, __func__);
196
197 ip = VTOI(vp);
198 if ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_UPDATE)) == 0)
199 return;
200 if ((vp->v_type == VBLK || vp->v_type == VCHR))
201 ip->i_flag |= IN_LAZYMOD;
202 else
203 ip->i_flag |= IN_MODIFIED;
204 if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
205 vfs_timestamp(&ts);
206 if (ip->i_flag & IN_ACCESS) {
207 ip->i_atime = ts.tv_sec;
208 ip->i_atimensec = ts.tv_nsec;
209 }
210 if (ip->i_flag & IN_UPDATE) {
211 ip->i_mtime = ts.tv_sec;
212 ip->i_mtimensec = ts.tv_nsec;
213 ip->i_modrev++;
214 }
215 if (ip->i_flag & IN_CHANGE) {
216 ip->i_ctime = ts.tv_sec;
217 ip->i_ctimensec = ts.tv_nsec;
218 }
219 }
220 ip->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE);
221 }
222
223 void
224 ext2_itimes(struct vnode *vp)
225 {
226
227 VI_LOCK(vp);
228 ext2_itimes_locked(vp);
229 VI_UNLOCK(vp);
230 }
231
232 /*
233 * Create a regular file
234 */
235 static int
236 ext2_create(struct vop_create_args *ap)
237 {
238 int error;
239
240 error =
241 ext2_makeinode(MAKEIMODE(ap->a_vap->va_type, ap->a_vap->va_mode),
242 ap->a_dvp, ap->a_vpp, ap->a_cnp);
243 if (error != 0)
244 return (error);
245 if ((ap->a_cnp->cn_flags & MAKEENTRY) != 0)
246 cache_enter(ap->a_dvp, *ap->a_vpp, ap->a_cnp);
247 return (0);
248 }
249
250 static int
251 ext2_open(struct vop_open_args *ap)
252 {
253
254 if (ap->a_vp->v_type == VBLK || ap->a_vp->v_type == VCHR)
255 return (EOPNOTSUPP);
256
257 /*
258 * Files marked append-only must be opened for appending.
259 */
260 if ((VTOI(ap->a_vp)->i_flags & APPEND) &&
261 (ap->a_mode & (FWRITE | O_APPEND)) == FWRITE)
262 return (EPERM);
263
264 vnode_create_vobject(ap->a_vp, VTOI(ap->a_vp)->i_size, ap->a_td);
265
266 return (0);
267 }
268
269 /*
270 * Close called.
271 *
272 * Update the times on the inode.
273 */
274 static int
275 ext2_close(struct vop_close_args *ap)
276 {
277 struct vnode *vp = ap->a_vp;
278
279 VI_LOCK(vp);
280 if (vp->v_usecount > 1)
281 ext2_itimes_locked(vp);
282 VI_UNLOCK(vp);
283 return (0);
284 }
285
286 static int
287 ext2_access(struct vop_access_args *ap)
288 {
289 struct vnode *vp = ap->a_vp;
290 struct inode *ip = VTOI(vp);
291 accmode_t accmode = ap->a_accmode;
292 int error;
293
294 if (vp->v_type == VBLK || vp->v_type == VCHR)
295 return (EOPNOTSUPP);
296
297 /*
298 * Disallow write attempts on read-only file systems;
299 * unless the file is a socket, fifo, or a block or
300 * character device resident on the file system.
301 */
302 if (accmode & VWRITE) {
303 switch (vp->v_type) {
304 case VDIR:
305 case VLNK:
306 case VREG:
307 if (vp->v_mount->mnt_flag & MNT_RDONLY)
308 return (EROFS);
309 break;
310 default:
311 break;
312 }
313 }
314
315 /* If immutable bit set, nobody gets to write it. */
316 if ((accmode & VWRITE) && (ip->i_flags & (SF_IMMUTABLE | SF_SNAPSHOT)))
317 return (EPERM);
318
319 error = vaccess(vp->v_type, ip->i_mode, ip->i_uid, ip->i_gid,
320 ap->a_accmode, ap->a_cred, NULL);
321 return (error);
322 }
323
324 static int
325 ext2_getattr(struct vop_getattr_args *ap)
326 {
327 struct vnode *vp = ap->a_vp;
328 struct inode *ip = VTOI(vp);
329 struct vattr *vap = ap->a_vap;
330
331 ext2_itimes(vp);
332 /*
333 * Copy from inode table
334 */
335 vap->va_fsid = dev2udev(ip->i_devvp->v_rdev);
336 vap->va_fileid = ip->i_number;
337 vap->va_mode = ip->i_mode & ~IFMT;
338 vap->va_nlink = ip->i_nlink;
339 vap->va_uid = ip->i_uid;
340 vap->va_gid = ip->i_gid;
341 vap->va_rdev = ip->i_rdev;
342 vap->va_size = ip->i_size;
343 vap->va_atime.tv_sec = ip->i_atime;
344 vap->va_atime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_atimensec : 0;
345 vap->va_mtime.tv_sec = ip->i_mtime;
346 vap->va_mtime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_mtimensec : 0;
347 vap->va_ctime.tv_sec = ip->i_ctime;
348 vap->va_ctime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_ctimensec : 0;
349 if E2DI_HAS_XTIME(ip) {
350 vap->va_birthtime.tv_sec = ip->i_birthtime;
351 vap->va_birthtime.tv_nsec = ip->i_birthnsec;
352 }
353 vap->va_flags = ip->i_flags;
354 vap->va_gen = ip->i_gen;
355 vap->va_blocksize = vp->v_mount->mnt_stat.f_iosize;
356 vap->va_bytes = dbtob((u_quad_t)ip->i_blocks);
357 vap->va_type = IFTOVT(ip->i_mode);
358 vap->va_filerev = ip->i_modrev;
359 return (0);
360 }
361
362 /*
363 * Set attribute vnode op. called from several syscalls
364 */
365 static int
366 ext2_setattr(struct vop_setattr_args *ap)
367 {
368 struct vattr *vap = ap->a_vap;
369 struct vnode *vp = ap->a_vp;
370 struct inode *ip = VTOI(vp);
371 struct ucred *cred = ap->a_cred;
372 struct thread *td = curthread;
373 int error;
374
375 /*
376 * Check for unsettable attributes.
377 */
378 if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
379 (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
380 (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
381 ((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
382 return (EINVAL);
383 }
384 if (vap->va_flags != VNOVAL) {
385 /* Disallow flags not supported by ext2fs. */
386 if(vap->va_flags & ~(SF_APPEND | SF_IMMUTABLE | UF_NODUMP))
387 return (EOPNOTSUPP);
388
389 if (vp->v_mount->mnt_flag & MNT_RDONLY)
390 return (EROFS);
391 /*
392 * Callers may only modify the file flags on objects they
393 * have VADMIN rights for.
394 */
395 if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
396 return (error);
397 /*
398 * Unprivileged processes and privileged processes in
399 * jail() are not permitted to unset system flags, or
400 * modify flags if any system flags are set.
401 * Privileged non-jail processes may not modify system flags
402 * if securelevel > 0 and any existing system flags are set.
403 */
404 if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) {
405 if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND)) {
406 error = securelevel_gt(cred, 0);
407 if (error)
408 return (error);
409 }
410 } else {
411 if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND) ||
412 ((vap->va_flags ^ ip->i_flags) & SF_SETTABLE))
413 return (EPERM);
414 }
415 ip->i_flags = vap->va_flags;
416 ip->i_flag |= IN_CHANGE;
417 if (ip->i_flags & (IMMUTABLE | APPEND))
418 return (0);
419 }
420 if (ip->i_flags & (IMMUTABLE | APPEND))
421 return (EPERM);
422 /*
423 * Go through the fields and update iff not VNOVAL.
424 */
425 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
426 if (vp->v_mount->mnt_flag & MNT_RDONLY)
427 return (EROFS);
428 if ((error = ext2_chown(vp, vap->va_uid, vap->va_gid, cred,
429 td)) != 0)
430 return (error);
431 }
432 if (vap->va_size != VNOVAL) {
433 /*
434 * Disallow write attempts on read-only file systems;
435 * unless the file is a socket, fifo, or a block or
436 * character device resident on the file system.
437 */
438 switch (vp->v_type) {
439 case VDIR:
440 return (EISDIR);
441 case VLNK:
442 case VREG:
443 if (vp->v_mount->mnt_flag & MNT_RDONLY)
444 return (EROFS);
445 break;
446 default:
447 break;
448 }
449 if ((error = ext2_truncate(vp, vap->va_size, 0, cred, td)) != 0)
450 return (error);
451 }
452 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
453 if (vp->v_mount->mnt_flag & MNT_RDONLY)
454 return (EROFS);
455 /*
456 * From utimes(2):
457 * If times is NULL, ... The caller must be the owner of
458 * the file, have permission to write the file, or be the
459 * super-user.
460 * If times is non-NULL, ... The caller must be the owner of
461 * the file or be the super-user.
462 */
463 if ((error = VOP_ACCESS(vp, VADMIN, cred, td)) &&
464 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
465 (error = VOP_ACCESS(vp, VWRITE, cred, td))))
466 return (error);
467 if (vap->va_atime.tv_sec != VNOVAL)
468 ip->i_flag |= IN_ACCESS;
469 if (vap->va_mtime.tv_sec != VNOVAL)
470 ip->i_flag |= IN_CHANGE | IN_UPDATE;
471 ext2_itimes(vp);
472 if (vap->va_atime.tv_sec != VNOVAL) {
473 ip->i_atime = vap->va_atime.tv_sec;
474 ip->i_atimensec = vap->va_atime.tv_nsec;
475 }
476 if (vap->va_mtime.tv_sec != VNOVAL) {
477 ip->i_mtime = vap->va_mtime.tv_sec;
478 ip->i_mtimensec = vap->va_mtime.tv_nsec;
479 }
480 ip->i_birthtime = vap->va_birthtime.tv_sec;
481 ip->i_birthnsec = vap->va_birthtime.tv_nsec;
482 error = ext2_update(vp, 0);
483 if (error)
484 return (error);
485 }
486 error = 0;
487 if (vap->va_mode != (mode_t)VNOVAL) {
488 if (vp->v_mount->mnt_flag & MNT_RDONLY)
489 return (EROFS);
490 error = ext2_chmod(vp, (int)vap->va_mode, cred, td);
491 }
492 return (error);
493 }
494
495 /*
496 * Change the mode on a file.
497 * Inode must be locked before calling.
498 */
499 static int
500 ext2_chmod(struct vnode *vp, int mode, struct ucred *cred, struct thread *td)
501 {
502 struct inode *ip = VTOI(vp);
503 int error;
504
505 /*
506 * To modify the permissions on a file, must possess VADMIN
507 * for that file.
508 */
509 if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
510 return (error);
511 /*
512 * Privileged processes may set the sticky bit on non-directories,
513 * as well as set the setgid bit on a file with a group that the
514 * process is not a member of.
515 */
516 if (vp->v_type != VDIR && (mode & S_ISTXT)) {
517 error = priv_check_cred(cred, PRIV_VFS_STICKYFILE, 0);
518 if (error)
519 return (EFTYPE);
520 }
521 if (!groupmember(ip->i_gid, cred) && (mode & ISGID)) {
522 error = priv_check_cred(cred, PRIV_VFS_SETGID, 0);
523 if (error)
524 return (error);
525 }
526 ip->i_mode &= ~ALLPERMS;
527 ip->i_mode |= (mode & ALLPERMS);
528 ip->i_flag |= IN_CHANGE;
529 return (0);
530 }
531
532 /*
533 * Perform chown operation on inode ip;
534 * inode must be locked prior to call.
535 */
536 static int
537 ext2_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred,
538 struct thread *td)
539 {
540 struct inode *ip = VTOI(vp);
541 uid_t ouid;
542 gid_t ogid;
543 int error = 0;
544
545 if (uid == (uid_t)VNOVAL)
546 uid = ip->i_uid;
547 if (gid == (gid_t)VNOVAL)
548 gid = ip->i_gid;
549 /*
550 * To modify the ownership of a file, must possess VADMIN
551 * for that file.
552 */
553 if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
554 return (error);
555 /*
556 * To change the owner of a file, or change the group of a file
557 * to a group of which we are not a member, the caller must
558 * have privilege.
559 */
560 if (uid != ip->i_uid || (gid != ip->i_gid &&
561 !groupmember(gid, cred))) {
562 error = priv_check_cred(cred, PRIV_VFS_CHOWN, 0);
563 if (error)
564 return (error);
565 }
566 ogid = ip->i_gid;
567 ouid = ip->i_uid;
568 ip->i_gid = gid;
569 ip->i_uid = uid;
570 ip->i_flag |= IN_CHANGE;
571 if ((ip->i_mode & (ISUID | ISGID)) && (ouid != uid || ogid != gid)) {
572 if (priv_check_cred(cred, PRIV_VFS_RETAINSUGID, 0) != 0)
573 ip->i_mode &= ~(ISUID | ISGID);
574 }
575 return (0);
576 }
577
578 /*
579 * Synch an open file.
580 */
581 /* ARGSUSED */
582 static int
583 ext2_fsync(struct vop_fsync_args *ap)
584 {
585 /*
586 * Flush all dirty buffers associated with a vnode.
587 */
588
589 vop_stdfsync(ap);
590
591 return (ext2_update(ap->a_vp, ap->a_waitfor == MNT_WAIT));
592 }
593
594 /*
595 * Mknod vnode call
596 */
597 /* ARGSUSED */
598 static int
599 ext2_mknod(struct vop_mknod_args *ap)
600 {
601 struct vattr *vap = ap->a_vap;
602 struct vnode **vpp = ap->a_vpp;
603 struct inode *ip;
604 ino_t ino;
605 int error;
606
607 error = ext2_makeinode(MAKEIMODE(vap->va_type, vap->va_mode),
608 ap->a_dvp, vpp, ap->a_cnp);
609 if (error)
610 return (error);
611 ip = VTOI(*vpp);
612 ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
613 if (vap->va_rdev != VNOVAL) {
614 /*
615 * Want to be able to use this to make badblock
616 * inodes, so don't truncate the dev number.
617 */
618 ip->i_rdev = vap->va_rdev;
619 }
620 /*
621 * Remove inode, then reload it through VFS_VGET so it is
622 * checked to see if it is an alias of an existing entry in
623 * the inode cache. XXX I don't believe this is necessary now.
624 */
625 (*vpp)->v_type = VNON;
626 ino = ip->i_number; /* Save this before vgone() invalidates ip. */
627 vgone(*vpp);
628 vput(*vpp);
629 error = VFS_VGET(ap->a_dvp->v_mount, ino, LK_EXCLUSIVE, vpp);
630 if (error) {
631 *vpp = NULL;
632 return (error);
633 }
634 return (0);
635 }
636
637 static int
638 ext2_remove(struct vop_remove_args *ap)
639 {
640 struct inode *ip;
641 struct vnode *vp = ap->a_vp;
642 struct vnode *dvp = ap->a_dvp;
643 int error;
644
645 ip = VTOI(vp);
646 if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
647 (VTOI(dvp)->i_flags & APPEND)) {
648 error = EPERM;
649 goto out;
650 }
651 error = ext2_dirremove(dvp, ap->a_cnp);
652 if (error == 0) {
653 ip->i_nlink--;
654 ip->i_flag |= IN_CHANGE;
655 }
656 out:
657 return (error);
658 }
659
660 /*
661 * link vnode call
662 */
663 static int
664 ext2_link(struct vop_link_args *ap)
665 {
666 struct vnode *vp = ap->a_vp;
667 struct vnode *tdvp = ap->a_tdvp;
668 struct componentname *cnp = ap->a_cnp;
669 struct inode *ip;
670 int error;
671
672 #ifdef INVARIANTS
673 if ((cnp->cn_flags & HASBUF) == 0)
674 panic("ext2_link: no name");
675 #endif
676 ip = VTOI(vp);
677 if ((nlink_t)ip->i_nlink >= EXT2_LINK_MAX) {
678 error = EMLINK;
679 goto out;
680 }
681 if (ip->i_flags & (IMMUTABLE | APPEND)) {
682 error = EPERM;
683 goto out;
684 }
685 ip->i_nlink++;
686 ip->i_flag |= IN_CHANGE;
687 error = ext2_update(vp, !DOINGASYNC(vp));
688 if (!error)
689 error = ext2_direnter(ip, tdvp, cnp);
690 if (error) {
691 ip->i_nlink--;
692 ip->i_flag |= IN_CHANGE;
693 }
694 out:
695 return (error);
696 }
697
698 /*
699 * Rename system call.
700 * rename("foo", "bar");
701 * is essentially
702 * unlink("bar");
703 * link("foo", "bar");
704 * unlink("foo");
705 * but ``atomically''. Can't do full commit without saving state in the
706 * inode on disk which isn't feasible at this time. Best we can do is
707 * always guarantee the target exists.
708 *
709 * Basic algorithm is:
710 *
711 * 1) Bump link count on source while we're linking it to the
712 * target. This also ensure the inode won't be deleted out
713 * from underneath us while we work (it may be truncated by
714 * a concurrent `trunc' or `open' for creation).
715 * 2) Link source to destination. If destination already exists,
716 * delete it first.
717 * 3) Unlink source reference to inode if still around. If a
718 * directory was moved and the parent of the destination
719 * is different from the source, patch the ".." entry in the
720 * directory.
721 */
722 static int
723 ext2_rename(struct vop_rename_args *ap)
724 {
725 struct vnode *tvp = ap->a_tvp;
726 struct vnode *tdvp = ap->a_tdvp;
727 struct vnode *fvp = ap->a_fvp;
728 struct vnode *fdvp = ap->a_fdvp;
729 struct componentname *tcnp = ap->a_tcnp;
730 struct componentname *fcnp = ap->a_fcnp;
731 struct inode *ip, *xp, *dp;
732 struct dirtemplate dirbuf;
733 int doingdirectory = 0, oldparent = 0, newparent = 0;
734 int error = 0;
735 u_char namlen;
736
737 #ifdef INVARIANTS
738 if ((tcnp->cn_flags & HASBUF) == 0 ||
739 (fcnp->cn_flags & HASBUF) == 0)
740 panic("ext2_rename: no name");
741 #endif
742 /*
743 * Check for cross-device rename.
744 */
745 if ((fvp->v_mount != tdvp->v_mount) ||
746 (tvp && (fvp->v_mount != tvp->v_mount))) {
747 error = EXDEV;
748 abortit:
749 if (tdvp == tvp)
750 vrele(tdvp);
751 else
752 vput(tdvp);
753 if (tvp)
754 vput(tvp);
755 vrele(fdvp);
756 vrele(fvp);
757 return (error);
758 }
759
760 if (tvp && ((VTOI(tvp)->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
761 (VTOI(tdvp)->i_flags & APPEND))) {
762 error = EPERM;
763 goto abortit;
764 }
765
766 /*
767 * Renaming a file to itself has no effect. The upper layers should
768 * not call us in that case. Temporarily just warn if they do.
769 */
770 if (fvp == tvp) {
771 printf("ext2_rename: fvp == tvp (can't happen)\n");
772 error = 0;
773 goto abortit;
774 }
775
776 if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
777 goto abortit;
778 dp = VTOI(fdvp);
779 ip = VTOI(fvp);
780 if (ip->i_nlink >= EXT2_LINK_MAX) {
781 VOP_UNLOCK(fvp, 0);
782 error = EMLINK;
783 goto abortit;
784 }
785 if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))
786 || (dp->i_flags & APPEND)) {
787 VOP_UNLOCK(fvp, 0);
788 error = EPERM;
789 goto abortit;
790 }
791 if ((ip->i_mode & IFMT) == IFDIR) {
792 /*
793 * Avoid ".", "..", and aliases of "." for obvious reasons.
794 */
795 if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
796 dp == ip || (fcnp->cn_flags | tcnp->cn_flags) & ISDOTDOT ||
797 (ip->i_flag & IN_RENAME)) {
798 VOP_UNLOCK(fvp, 0);
799 error = EINVAL;
800 goto abortit;
801 }
802 ip->i_flag |= IN_RENAME;
803 oldparent = dp->i_number;
804 doingdirectory++;
805 }
806 vrele(fdvp);
807
808 /*
809 * When the target exists, both the directory
810 * and target vnodes are returned locked.
811 */
812 dp = VTOI(tdvp);
813 xp = NULL;
814 if (tvp)
815 xp = VTOI(tvp);
816
817 /*
818 * 1) Bump link count while we're moving stuff
819 * around. If we crash somewhere before
820 * completing our work, the link count
821 * may be wrong, but correctable.
822 */
823 ip->i_nlink++;
824 ip->i_flag |= IN_CHANGE;
825 if ((error = ext2_update(fvp, !DOINGASYNC(fvp))) != 0) {
826 VOP_UNLOCK(fvp, 0);
827 goto bad;
828 }
829
830 /*
831 * If ".." must be changed (ie the directory gets a new
832 * parent) then the source directory must not be in the
833 * directory hierarchy above the target, as this would
834 * orphan everything below the source directory. Also
835 * the user must have write permission in the source so
836 * as to be able to change "..". We must repeat the call
837 * to namei, as the parent directory is unlocked by the
838 * call to checkpath().
839 */
840 error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_thread);
841 VOP_UNLOCK(fvp, 0);
842 if (oldparent != dp->i_number)
843 newparent = dp->i_number;
844 if (doingdirectory && newparent) {
845 if (error) /* write access check above */
846 goto bad;
847 if (xp != NULL)
848 vput(tvp);
849 error = ext2_checkpath(ip, dp, tcnp->cn_cred);
850 if (error)
851 goto out;
852 VREF(tdvp);
853 error = relookup(tdvp, &tvp, tcnp);
854 if (error)
855 goto out;
856 vrele(tdvp);
857 dp = VTOI(tdvp);
858 xp = NULL;
859 if (tvp)
860 xp = VTOI(tvp);
861 }
862 /*
863 * 2) If target doesn't exist, link the target
864 * to the source and unlink the source.
865 * Otherwise, rewrite the target directory
866 * entry to reference the source inode and
867 * expunge the original entry's existence.
868 */
869 if (xp == NULL) {
870 if (dp->i_devvp != ip->i_devvp)
871 panic("ext2_rename: EXDEV");
872 /*
873 * Account for ".." in new directory.
874 * When source and destination have the same
875 * parent we don't fool with the link count.
876 */
877 if (doingdirectory && newparent) {
878 if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) {
879 error = EMLINK;
880 goto bad;
881 }
882 dp->i_nlink++;
883 dp->i_flag |= IN_CHANGE;
884 error = ext2_update(tdvp, !DOINGASYNC(tdvp));
885 if (error)
886 goto bad;
887 }
888 error = ext2_direnter(ip, tdvp, tcnp);
889 if (error) {
890 if (doingdirectory && newparent) {
891 dp->i_nlink--;
892 dp->i_flag |= IN_CHANGE;
893 (void)ext2_update(tdvp, 1);
894 }
895 goto bad;
896 }
897 vput(tdvp);
898 } else {
899 if (xp->i_devvp != dp->i_devvp || xp->i_devvp != ip->i_devvp)
900 panic("ext2_rename: EXDEV");
901 /*
902 * Short circuit rename(foo, foo).
903 */
904 if (xp->i_number == ip->i_number)
905 panic("ext2_rename: same file");
906 /*
907 * If the parent directory is "sticky", then the user must
908 * own the parent directory, or the destination of the rename,
909 * otherwise the destination may not be changed (except by
910 * root). This implements append-only directories.
911 */
912 if ((dp->i_mode & S_ISTXT) && tcnp->cn_cred->cr_uid != 0 &&
913 tcnp->cn_cred->cr_uid != dp->i_uid &&
914 xp->i_uid != tcnp->cn_cred->cr_uid) {
915 error = EPERM;
916 goto bad;
917 }
918 /*
919 * Target must be empty if a directory and have no links
920 * to it. Also, ensure source and target are compatible
921 * (both directories, or both not directories).
922 */
923 if ((xp->i_mode&IFMT) == IFDIR) {
924 if (! ext2_dirempty(xp, dp->i_number, tcnp->cn_cred) ||
925 xp->i_nlink > 2) {
926 error = ENOTEMPTY;
927 goto bad;
928 }
929 if (!doingdirectory) {
930 error = ENOTDIR;
931 goto bad;
932 }
933 cache_purge(tdvp);
934 } else if (doingdirectory) {
935 error = EISDIR;
936 goto bad;
937 }
938 error = ext2_dirrewrite(dp, ip, tcnp);
939 if (error)
940 goto bad;
941 /*
942 * If the target directory is in the same
943 * directory as the source directory,
944 * decrement the link count on the parent
945 * of the target directory.
946 */
947 if (doingdirectory && !newparent) {
948 dp->i_nlink--;
949 dp->i_flag |= IN_CHANGE;
950 }
951 vput(tdvp);
952 /*
953 * Adjust the link count of the target to
954 * reflect the dirrewrite above. If this is
955 * a directory it is empty and there are
956 * no links to it, so we can squash the inode and
957 * any space associated with it. We disallowed
958 * renaming over top of a directory with links to
959 * it above, as the remaining link would point to
960 * a directory without "." or ".." entries.
961 */
962 xp->i_nlink--;
963 if (doingdirectory) {
964 if (--xp->i_nlink != 0)
965 panic("ext2_rename: linked directory");
966 error = ext2_truncate(tvp, (off_t)0, IO_SYNC,
967 tcnp->cn_cred, tcnp->cn_thread);
968 }
969 xp->i_flag |= IN_CHANGE;
970 vput(tvp);
971 xp = NULL;
972 }
973
974 /*
975 * 3) Unlink the source.
976 */
977 fcnp->cn_flags &= ~MODMASK;
978 fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
979 VREF(fdvp);
980 error = relookup(fdvp, &fvp, fcnp);
981 if (error == 0)
982 vrele(fdvp);
983 if (fvp != NULL) {
984 xp = VTOI(fvp);
985 dp = VTOI(fdvp);
986 } else {
987 /*
988 * From name has disappeared. IN_RENAME is not sufficient
989 * to protect against directory races due to timing windows,
990 * so we can't panic here.
991 */
992 vrele(ap->a_fvp);
993 return (0);
994 }
995 /*
996 * Ensure that the directory entry still exists and has not
997 * changed while the new name has been entered. If the source is
998 * a file then the entry may have been unlinked or renamed. In
999 * either case there is no further work to be done. If the source
1000 * is a directory then it cannot have been rmdir'ed; its link
1001 * count of three would cause a rmdir to fail with ENOTEMPTY.
1002 * The IN_RENAME flag ensures that it cannot be moved by another
1003 * rename.
1004 */
1005 if (xp != ip) {
1006 /*
1007 * From name resolves to a different inode. IN_RENAME is
1008 * not sufficient protection against timing window races
1009 * so we can't panic here.
1010 */
1011 } else {
1012 /*
1013 * If the source is a directory with a
1014 * new parent, the link count of the old
1015 * parent directory must be decremented
1016 * and ".." set to point to the new parent.
1017 */
1018 if (doingdirectory && newparent) {
1019 dp->i_nlink--;
1020 dp->i_flag |= IN_CHANGE;
1021 error = vn_rdwr(UIO_READ, fvp, (caddr_t)&dirbuf,
1022 sizeof(struct dirtemplate), (off_t)0,
1023 UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK,
1024 tcnp->cn_cred, NOCRED, NULL, NULL);
1025 if (error == 0) {
1026 /* Like ufs little-endian: */
1027 namlen = dirbuf.dotdot_type;
1028 if (namlen != 2 ||
1029 dirbuf.dotdot_name[0] != '.' ||
1030 dirbuf.dotdot_name[1] != '.') {
1031 ext2_dirbad(xp, (doff_t)12,
1032 "rename: mangled dir");
1033 } else {
1034 dirbuf.dotdot_ino = newparent;
1035 (void) vn_rdwr(UIO_WRITE, fvp,
1036 (caddr_t)&dirbuf,
1037 sizeof(struct dirtemplate),
1038 (off_t)0, UIO_SYSSPACE,
1039 IO_NODELOCKED | IO_SYNC |
1040 IO_NOMACCHECK, tcnp->cn_cred,
1041 NOCRED, NULL, NULL);
1042 cache_purge(fdvp);
1043 }
1044 }
1045 }
1046 error = ext2_dirremove(fdvp, fcnp);
1047 if (!error) {
1048 xp->i_nlink--;
1049 xp->i_flag |= IN_CHANGE;
1050 }
1051 xp->i_flag &= ~IN_RENAME;
1052 }
1053 if (dp)
1054 vput(fdvp);
1055 if (xp)
1056 vput(fvp);
1057 vrele(ap->a_fvp);
1058 return (error);
1059
1060 bad:
1061 if (xp)
1062 vput(ITOV(xp));
1063 vput(ITOV(dp));
1064 out:
1065 if (doingdirectory)
1066 ip->i_flag &= ~IN_RENAME;
1067 if (vn_lock(fvp, LK_EXCLUSIVE) == 0) {
1068 ip->i_nlink--;
1069 ip->i_flag |= IN_CHANGE;
1070 ip->i_flag &= ~IN_RENAME;
1071 vput(fvp);
1072 } else
1073 vrele(fvp);
1074 return (error);
1075 }
1076
1077 /*
1078 * Mkdir system call
1079 */
1080 static int
1081 ext2_mkdir(struct vop_mkdir_args *ap)
1082 {
1083 struct vnode *dvp = ap->a_dvp;
1084 struct vattr *vap = ap->a_vap;
1085 struct componentname *cnp = ap->a_cnp;
1086 struct inode *ip, *dp;
1087 struct vnode *tvp;
1088 struct dirtemplate dirtemplate, *dtp;
1089 int error, dmode;
1090
1091 #ifdef INVARIANTS
1092 if ((cnp->cn_flags & HASBUF) == 0)
1093 panic("ext2_mkdir: no name");
1094 #endif
1095 dp = VTOI(dvp);
1096 if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) {
1097 error = EMLINK;
1098 goto out;
1099 }
1100 dmode = vap->va_mode & 0777;
1101 dmode |= IFDIR;
1102 /*
1103 * Must simulate part of ext2_makeinode here to acquire the inode,
1104 * but not have it entered in the parent directory. The entry is
1105 * made later after writing "." and ".." entries.
1106 */
1107 error = ext2_valloc(dvp, dmode, cnp->cn_cred, &tvp);
1108 if (error)
1109 goto out;
1110 ip = VTOI(tvp);
1111 ip->i_gid = dp->i_gid;
1112 #ifdef SUIDDIR
1113 {
1114 /*
1115 * if we are hacking owners here, (only do this where told to)
1116 * and we are not giving it TOO root, (would subvert quotas)
1117 * then go ahead and give it to the other user.
1118 * The new directory also inherits the SUID bit.
1119 * If user's UID and dir UID are the same,
1120 * 'give it away' so that the SUID is still forced on.
1121 */
1122 if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
1123 (dp->i_mode & ISUID) && dp->i_uid) {
1124 dmode |= ISUID;
1125 ip->i_uid = dp->i_uid;
1126 } else {
1127 ip->i_uid = cnp->cn_cred->cr_uid;
1128 }
1129 }
1130 #else
1131 ip->i_uid = cnp->cn_cred->cr_uid;
1132 #endif
1133 ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
1134 ip->i_mode = dmode;
1135 tvp->v_type = VDIR; /* Rest init'd in getnewvnode(). */
1136 ip->i_nlink = 2;
1137 if (cnp->cn_flags & ISWHITEOUT)
1138 ip->i_flags |= UF_OPAQUE;
1139 error = ext2_update(tvp, 1);
1140
1141 /*
1142 * Bump link count in parent directory
1143 * to reflect work done below. Should
1144 * be done before reference is created
1145 * so reparation is possible if we crash.
1146 */
1147 dp->i_nlink++;
1148 dp->i_flag |= IN_CHANGE;
1149 error = ext2_update(dvp, !DOINGASYNC(dvp));
1150 if (error)
1151 goto bad;
1152
1153 /* Initialize directory with "." and ".." from static template. */
1154 if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
1155 EXT2F_INCOMPAT_FTYPE))
1156 dtp = &mastertemplate;
1157 else
1158 dtp = &omastertemplate;
1159 dirtemplate = *dtp;
1160 dirtemplate.dot_ino = ip->i_number;
1161 dirtemplate.dotdot_ino = dp->i_number;
1162 /* note that in ext2 DIRBLKSIZ == blocksize, not DEV_BSIZE
1163 * so let's just redefine it - for this function only
1164 */
1165 #undef DIRBLKSIZ
1166 #define DIRBLKSIZ VTOI(dvp)->i_e2fs->e2fs_bsize
1167 dirtemplate.dotdot_reclen = DIRBLKSIZ - 12;
1168 error = vn_rdwr(UIO_WRITE, tvp, (caddr_t)&dirtemplate,
1169 sizeof(dirtemplate), (off_t)0, UIO_SYSSPACE,
1170 IO_NODELOCKED | IO_SYNC | IO_NOMACCHECK, cnp->cn_cred, NOCRED,
1171 NULL, NULL);
1172 if (error) {
1173 dp->i_nlink--;
1174 dp->i_flag |= IN_CHANGE;
1175 goto bad;
1176 }
1177 if (DIRBLKSIZ > VFSTOEXT2(dvp->v_mount)->um_mountp->mnt_stat.f_bsize)
1178 /* XXX should grow with balloc() */
1179 panic("ext2_mkdir: blksize");
1180 else {
1181 ip->i_size = DIRBLKSIZ;
1182 ip->i_flag |= IN_CHANGE;
1183 }
1184
1185 /* Directory set up, now install its entry in the parent directory. */
1186 error = ext2_direnter(ip, dvp, cnp);
1187 if (error) {
1188 dp->i_nlink--;
1189 dp->i_flag |= IN_CHANGE;
1190 }
1191 bad:
1192 /*
1193 * No need to do an explicit VOP_TRUNCATE here, vrele will do this
1194 * for us because we set the link count to 0.
1195 */
1196 if (error) {
1197 ip->i_nlink = 0;
1198 ip->i_flag |= IN_CHANGE;
1199 vput(tvp);
1200 } else
1201 *ap->a_vpp = tvp;
1202 out:
1203 return (error);
1204 #undef DIRBLKSIZ
1205 #define DIRBLKSIZ DEV_BSIZE
1206 }
1207
1208 /*
1209 * Rmdir system call.
1210 */
1211 static int
1212 ext2_rmdir(struct vop_rmdir_args *ap)
1213 {
1214 struct vnode *vp = ap->a_vp;
1215 struct vnode *dvp = ap->a_dvp;
1216 struct componentname *cnp = ap->a_cnp;
1217 struct inode *ip, *dp;
1218 int error;
1219
1220 ip = VTOI(vp);
1221 dp = VTOI(dvp);
1222
1223 /*
1224 * Verify the directory is empty (and valid).
1225 * (Rmdir ".." won't be valid since
1226 * ".." will contain a reference to
1227 * the current directory and thus be
1228 * non-empty.)
1229 */
1230 if (ip->i_nlink != 2 || !ext2_dirempty(ip, dp->i_number, cnp->cn_cred)) {
1231 error = ENOTEMPTY;
1232 goto out;
1233 }
1234 if ((dp->i_flags & APPEND)
1235 || (ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
1236 error = EPERM;
1237 goto out;
1238 }
1239 /*
1240 * Delete reference to directory before purging
1241 * inode. If we crash in between, the directory
1242 * will be reattached to lost+found,
1243 */
1244 error = ext2_dirremove(dvp, cnp);
1245 if (error)
1246 goto out;
1247 dp->i_nlink--;
1248 dp->i_flag |= IN_CHANGE;
1249 cache_purge(dvp);
1250 VOP_UNLOCK(dvp, 0);
1251 /*
1252 * Truncate inode. The only stuff left
1253 * in the directory is "." and "..". The
1254 * "." reference is inconsequential since
1255 * we're quashing it. The ".." reference
1256 * has already been adjusted above. We've
1257 * removed the "." reference and the reference
1258 * in the parent directory, but there may be
1259 * other hard links so decrement by 2 and
1260 * worry about them later.
1261 */
1262 ip->i_nlink -= 2;
1263 error = ext2_truncate(vp, (off_t)0, IO_SYNC, cnp->cn_cred,
1264 cnp->cn_thread);
1265 cache_purge(ITOV(ip));
1266 if (vn_lock(dvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
1267 VOP_UNLOCK(vp, 0);
1268 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
1269 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1270 }
1271 out:
1272 return (error);
1273 }
1274
1275 /*
1276 * symlink -- make a symbolic link
1277 */
1278 static int
1279 ext2_symlink(struct vop_symlink_args *ap)
1280 {
1281 struct vnode *vp, **vpp = ap->a_vpp;
1282 struct inode *ip;
1283 int len, error;
1284
1285 error = ext2_makeinode(IFLNK | ap->a_vap->va_mode, ap->a_dvp,
1286 vpp, ap->a_cnp);
1287 if (error)
1288 return (error);
1289 vp = *vpp;
1290 len = strlen(ap->a_target);
1291 if (len < vp->v_mount->mnt_maxsymlinklen) {
1292 ip = VTOI(vp);
1293 bcopy(ap->a_target, (char *)ip->i_shortlink, len);
1294 ip->i_size = len;
1295 ip->i_flag |= IN_CHANGE | IN_UPDATE;
1296 } else
1297 error = vn_rdwr(UIO_WRITE, vp, ap->a_target, len, (off_t)0,
1298 UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK,
1299 ap->a_cnp->cn_cred, NOCRED, NULL, NULL);
1300 if (error)
1301 vput(vp);
1302 return (error);
1303 }
1304
1305 /*
1306 * Return target name of a symbolic link
1307 */
1308 static int
1309 ext2_readlink(struct vop_readlink_args *ap)
1310 {
1311 struct vnode *vp = ap->a_vp;
1312 struct inode *ip = VTOI(vp);
1313 int isize;
1314
1315 isize = ip->i_size;
1316 if (isize < vp->v_mount->mnt_maxsymlinklen) {
1317 uiomove((char *)ip->i_shortlink, isize, ap->a_uio);
1318 return (0);
1319 }
1320 return (VOP_READ(vp, ap->a_uio, 0, ap->a_cred));
1321 }
1322
1323 /*
1324 * Calculate the logical to physical mapping if not done already,
1325 * then call the device strategy routine.
1326 *
1327 * In order to be able to swap to a file, the ext2_bmaparray() operation may not
1328 * deadlock on memory. See ext2_bmap() for details.
1329 */
1330 static int
1331 ext2_strategy(struct vop_strategy_args *ap)
1332 {
1333 struct buf *bp = ap->a_bp;
1334 struct vnode *vp = ap->a_vp;
1335 struct bufobj *bo;
1336 daddr_t blkno;
1337 int error;
1338
1339 if (vp->v_type == VBLK || vp->v_type == VCHR)
1340 panic("ext2_strategy: spec");
1341 if (bp->b_blkno == bp->b_lblkno) {
1342 error = ext2_bmaparray(vp, bp->b_lblkno, &blkno, NULL, NULL);
1343 bp->b_blkno = blkno;
1344 if (error) {
1345 bp->b_error = error;
1346 bp->b_ioflags |= BIO_ERROR;
1347 bufdone(bp);
1348 return (0);
1349 }
1350 if ((long)bp->b_blkno == -1)
1351 vfs_bio_clrbuf(bp);
1352 }
1353 if ((long)bp->b_blkno == -1) {
1354 bufdone(bp);
1355 return (0);
1356 }
1357 bp->b_iooffset = dbtob(bp->b_blkno);
1358 bo = VFSTOEXT2(vp->v_mount)->um_bo;
1359 BO_STRATEGY(bo, bp);
1360 return (0);
1361 }
1362
1363 /*
1364 * Print out the contents of an inode.
1365 */
1366 static int
1367 ext2_print(struct vop_print_args *ap)
1368 {
1369 struct vnode *vp = ap->a_vp;
1370 struct inode *ip = VTOI(vp);
1371
1372 vn_printf(ip->i_devvp, "\tino %lu", (u_long)ip->i_number);
1373 if (vp->v_type == VFIFO)
1374 fifo_printinfo(vp);
1375 printf("\n");
1376 return (0);
1377 }
1378
1379 /*
1380 * Close wrapper for fifos.
1381 *
1382 * Update the times on the inode then do device close.
1383 */
1384 static int
1385 ext2fifo_close(struct vop_close_args *ap)
1386 {
1387 struct vnode *vp = ap->a_vp;
1388
1389 VI_LOCK(vp);
1390 if (vp->v_usecount > 1)
1391 ext2_itimes_locked(vp);
1392 VI_UNLOCK(vp);
1393 return (fifo_specops.vop_close(ap));
1394 }
1395
1396 /*
1397 * Kqfilter wrapper for fifos.
1398 *
1399 * Fall through to ext2 kqfilter routines if needed
1400 */
1401 static int
1402 ext2fifo_kqfilter(struct vop_kqfilter_args *ap)
1403 {
1404 int error;
1405
1406 error = fifo_specops.vop_kqfilter(ap);
1407 if (error)
1408 error = vfs_kqfilter(ap);
1409 return (error);
1410 }
1411
1412 /*
1413 * Return POSIX pathconf information applicable to ext2 filesystems.
1414 */
1415 static int
1416 ext2_pathconf(struct vop_pathconf_args *ap)
1417 {
1418 int error = 0;
1419
1420 switch (ap->a_name) {
1421 case _PC_LINK_MAX:
1422 *ap->a_retval = EXT2_LINK_MAX;
1423 break;
1424 case _PC_NAME_MAX:
1425 *ap->a_retval = NAME_MAX;
1426 break;
1427 case _PC_PATH_MAX:
1428 *ap->a_retval = PATH_MAX;
1429 break;
1430 case _PC_PIPE_BUF:
1431 *ap->a_retval = PIPE_BUF;
1432 break;
1433 case _PC_CHOWN_RESTRICTED:
1434 *ap->a_retval = 1;
1435 break;
1436 case _PC_NO_TRUNC:
1437 *ap->a_retval = 1;
1438 break;
1439 case _PC_MIN_HOLE_SIZE:
1440 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize;
1441 break;
1442 case _PC_ASYNC_IO:
1443 /* _PC_ASYNC_IO should have been handled by upper layers. */
1444 KASSERT(0, ("_PC_ASYNC_IO should not get here"));
1445 error = EINVAL;
1446 break;
1447 case _PC_PRIO_IO:
1448 *ap->a_retval = 0;
1449 break;
1450 case _PC_SYNC_IO:
1451 *ap->a_retval = 0;
1452 break;
1453 case _PC_ALLOC_SIZE_MIN:
1454 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_bsize;
1455 break;
1456 case _PC_FILESIZEBITS:
1457 *ap->a_retval = 64;
1458 break;
1459 case _PC_REC_INCR_XFER_SIZE:
1460 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize;
1461 break;
1462 case _PC_REC_MAX_XFER_SIZE:
1463 *ap->a_retval = -1; /* means ``unlimited'' */
1464 break;
1465 case _PC_REC_MIN_XFER_SIZE:
1466 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize;
1467 break;
1468 case _PC_REC_XFER_ALIGN:
1469 *ap->a_retval = PAGE_SIZE;
1470 break;
1471 case _PC_SYMLINK_MAX:
1472 *ap->a_retval = MAXPATHLEN;
1473 break;
1474
1475 default:
1476 error = EINVAL;
1477 break;
1478 }
1479 return (error);
1480 }
1481
1482 /*
1483 * Vnode pointer to File handle
1484 */
1485 /* ARGSUSED */
1486 static int
1487 ext2_vptofh(struct vop_vptofh_args *ap)
1488 {
1489 struct inode *ip;
1490 struct ufid *ufhp;
1491
1492 ip = VTOI(ap->a_vp);
1493 ufhp = (struct ufid *)ap->a_fhp;
1494 ufhp->ufid_len = sizeof(struct ufid);
1495 ufhp->ufid_ino = ip->i_number;
1496 ufhp->ufid_gen = ip->i_gen;
1497 return (0);
1498 }
1499
1500 /*
1501 * Initialize the vnode associated with a new inode, handle aliased
1502 * vnodes.
1503 */
1504 int
1505 ext2_vinit(struct mount *mntp, struct vop_vector *fifoops, struct vnode **vpp)
1506 {
1507 struct inode *ip;
1508 struct vnode *vp;
1509
1510 vp = *vpp;
1511 ip = VTOI(vp);
1512 vp->v_type = IFTOVT(ip->i_mode);
1513 if (vp->v_type == VFIFO)
1514 vp->v_op = fifoops;
1515
1516 if (ip->i_number == EXT2_ROOTINO)
1517 vp->v_vflag |= VV_ROOT;
1518 ip->i_modrev = init_va_filerev();
1519 *vpp = vp;
1520 return (0);
1521 }
1522
1523 /*
1524 * Allocate a new inode.
1525 */
1526 static int
1527 ext2_makeinode(int mode, struct vnode *dvp, struct vnode **vpp,
1528 struct componentname *cnp)
1529 {
1530 struct inode *ip, *pdir;
1531 struct vnode *tvp;
1532 int error;
1533
1534 pdir = VTOI(dvp);
1535 #ifdef INVARIANTS
1536 if ((cnp->cn_flags & HASBUF) == 0)
1537 panic("ext2_makeinode: no name");
1538 #endif
1539 *vpp = NULL;
1540 if ((mode & IFMT) == 0)
1541 mode |= IFREG;
1542
1543 error = ext2_valloc(dvp, mode, cnp->cn_cred, &tvp);
1544 if (error) {
1545 return (error);
1546 }
1547 ip = VTOI(tvp);
1548 ip->i_gid = pdir->i_gid;
1549 #ifdef SUIDDIR
1550 {
1551 /*
1552 * if we are
1553 * not the owner of the directory,
1554 * and we are hacking owners here, (only do this where told to)
1555 * and we are not giving it TOO root, (would subvert quotas)
1556 * then go ahead and give it to the other user.
1557 * Note that this drops off the execute bits for security.
1558 */
1559 if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
1560 (pdir->i_mode & ISUID) &&
1561 (pdir->i_uid != cnp->cn_cred->cr_uid) && pdir->i_uid) {
1562 ip->i_uid = pdir->i_uid;
1563 mode &= ~07111;
1564 } else {
1565 ip->i_uid = cnp->cn_cred->cr_uid;
1566 }
1567 }
1568 #else
1569 ip->i_uid = cnp->cn_cred->cr_uid;
1570 #endif
1571 ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
1572 ip->i_mode = mode;
1573 tvp->v_type = IFTOVT(mode); /* Rest init'd in getnewvnode(). */
1574 ip->i_nlink = 1;
1575 if ((ip->i_mode & ISGID) && !groupmember(ip->i_gid, cnp->cn_cred)) {
1576 if (priv_check_cred(cnp->cn_cred, PRIV_VFS_RETAINSUGID, 0))
1577 ip->i_mode &= ~ISGID;
1578 }
1579
1580 if (cnp->cn_flags & ISWHITEOUT)
1581 ip->i_flags |= UF_OPAQUE;
1582
1583 /*
1584 * Make sure inode goes to disk before directory entry.
1585 */
1586 error = ext2_update(tvp, !DOINGASYNC(tvp));
1587 if (error)
1588 goto bad;
1589 error = ext2_direnter(ip, dvp, cnp);
1590 if (error)
1591 goto bad;
1592
1593 *vpp = tvp;
1594 return (0);
1595
1596 bad:
1597 /*
1598 * Write error occurred trying to update the inode
1599 * or the directory so must deallocate the inode.
1600 */
1601 ip->i_nlink = 0;
1602 ip->i_flag |= IN_CHANGE;
1603 vput(tvp);
1604 return (error);
1605 }
1606
1607 /*
1608 * Vnode op for reading.
1609 */
1610 static int
1611 ext2_read(struct vop_read_args *ap)
1612 {
1613 struct vnode *vp;
1614 struct inode *ip;
1615 int error;
1616
1617 vp = ap->a_vp;
1618 ip = VTOI(vp);
1619
1620 /*EXT4_EXT_LOCK(ip);*/
1621 if (ip->i_flag & IN_E4EXTENTS)
1622 error = ext4_ext_read(ap);
1623 else
1624 error = ext2_ind_read(ap);
1625 /*EXT4_EXT_UNLOCK(ip);*/
1626 return (error);
1627 }
1628
1629 /*
1630 * Vnode op for reading.
1631 */
1632 static int
1633 ext2_ind_read(struct vop_read_args *ap)
1634 {
1635 struct vnode *vp;
1636 struct inode *ip;
1637 struct uio *uio;
1638 struct m_ext2fs *fs;
1639 struct buf *bp;
1640 daddr_t lbn, nextlbn;
1641 off_t bytesinfile;
1642 long size, xfersize, blkoffset;
1643 int error, orig_resid, seqcount;
1644 int ioflag;
1645
1646 vp = ap->a_vp;
1647 uio = ap->a_uio;
1648 ioflag = ap->a_ioflag;
1649
1650 seqcount = ap->a_ioflag >> IO_SEQSHIFT;
1651 ip = VTOI(vp);
1652
1653 #ifdef INVARIANTS
1654 if (uio->uio_rw != UIO_READ)
1655 panic("%s: mode", "ext2_read");
1656
1657 if (vp->v_type == VLNK) {
1658 if ((int)ip->i_size < vp->v_mount->mnt_maxsymlinklen)
1659 panic("%s: short symlink", "ext2_read");
1660 } else if (vp->v_type != VREG && vp->v_type != VDIR)
1661 panic("%s: type %d", "ext2_read", vp->v_type);
1662 #endif
1663 orig_resid = uio->uio_resid;
1664 KASSERT(orig_resid >= 0, ("ext2_read: uio->uio_resid < 0"));
1665 if (orig_resid == 0)
1666 return (0);
1667 KASSERT(uio->uio_offset >= 0, ("ext2_read: uio->uio_offset < 0"));
1668 fs = ip->i_e2fs;
1669 if (uio->uio_offset < ip->i_size &&
1670 uio->uio_offset >= fs->e2fs_maxfilesize)
1671 return (EOVERFLOW);
1672
1673 for (error = 0, bp = NULL; uio->uio_resid > 0; bp = NULL) {
1674 if ((bytesinfile = ip->i_size - uio->uio_offset) <= 0)
1675 break;
1676 lbn = lblkno(fs, uio->uio_offset);
1677 nextlbn = lbn + 1;
1678 size = blksize(fs, ip, lbn);
1679 blkoffset = blkoff(fs, uio->uio_offset);
1680
1681 xfersize = fs->e2fs_fsize - blkoffset;
1682 if (uio->uio_resid < xfersize)
1683 xfersize = uio->uio_resid;
1684 if (bytesinfile < xfersize)
1685 xfersize = bytesinfile;
1686
1687 if (lblktosize(fs, nextlbn) >= ip->i_size)
1688 error = bread(vp, lbn, size, NOCRED, &bp);
1689 else if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
1690 error = cluster_read(vp, ip->i_size, lbn, size,
1691 NOCRED, blkoffset + uio->uio_resid, seqcount,
1692 0, &bp);
1693 } else if (seqcount > 1) {
1694 u_int nextsize = blksize(fs, ip, nextlbn);
1695 error = breadn(vp, lbn,
1696 size, &nextlbn, &nextsize, 1, NOCRED, &bp);
1697 } else
1698 error = bread(vp, lbn, size, NOCRED, &bp);
1699 if (error) {
1700 brelse(bp);
1701 bp = NULL;
1702 break;
1703 }
1704
1705 /*
1706 * If IO_DIRECT then set B_DIRECT for the buffer. This
1707 * will cause us to attempt to release the buffer later on
1708 * and will cause the buffer cache to attempt to free the
1709 * underlying pages.
1710 */
1711 if (ioflag & IO_DIRECT)
1712 bp->b_flags |= B_DIRECT;
1713
1714 /*
1715 * We should only get non-zero b_resid when an I/O error
1716 * has occurred, which should cause us to break above.
1717 * However, if the short read did not cause an error,
1718 * then we want to ensure that we do not uiomove bad
1719 * or uninitialized data.
1720 */
1721 size -= bp->b_resid;
1722 if (size < xfersize) {
1723 if (size == 0)
1724 break;
1725 xfersize = size;
1726 }
1727 error = uiomove((char *)bp->b_data + blkoffset,
1728 (int)xfersize, uio);
1729 if (error)
1730 break;
1731
1732 if (ioflag & (IO_VMIO|IO_DIRECT)) {
1733 /*
1734 * If it's VMIO or direct I/O, then we don't
1735 * need the buf, mark it available for
1736 * freeing. If it's non-direct VMIO, the VM has
1737 * the data.
1738 */
1739 bp->b_flags |= B_RELBUF;
1740 brelse(bp);
1741 } else {
1742 /*
1743 * Otherwise let whoever
1744 * made the request take care of
1745 * freeing it. We just queue
1746 * it onto another list.
1747 */
1748 bqrelse(bp);
1749 }
1750 }
1751
1752 /*
1753 * This can only happen in the case of an error
1754 * because the loop above resets bp to NULL on each iteration
1755 * and on normal completion has not set a new value into it.
1756 * so it must have come from a 'break' statement
1757 */
1758 if (bp != NULL) {
1759 if (ioflag & (IO_VMIO|IO_DIRECT)) {
1760 bp->b_flags |= B_RELBUF;
1761 brelse(bp);
1762 } else {
1763 bqrelse(bp);
1764 }
1765 }
1766
1767 if ((error == 0 || uio->uio_resid != orig_resid) &&
1768 (vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0)
1769 ip->i_flag |= IN_ACCESS;
1770 return (error);
1771 }
1772
1773 static int
1774 ext2_ioctl(struct vop_ioctl_args *ap)
1775 {
1776
1777 switch (ap->a_command) {
1778 case FIOSEEKDATA:
1779 case FIOSEEKHOLE:
1780 return (vn_bmap_seekhole(ap->a_vp, ap->a_command,
1781 (off_t *)ap->a_data, ap->a_cred));
1782 default:
1783 return (ENOTTY);
1784 }
1785 }
1786
1787 /*
1788 * this function handles ext4 extents block mapping
1789 */
1790 static int
1791 ext4_ext_read(struct vop_read_args *ap)
1792 {
1793 struct vnode *vp;
1794 struct inode *ip;
1795 struct uio *uio;
1796 struct m_ext2fs *fs;
1797 struct buf *bp;
1798 struct ext4_extent nex, *ep;
1799 struct ext4_extent_path path;
1800 daddr_t lbn, newblk;
1801 off_t bytesinfile;
1802 int cache_type;
1803 ssize_t orig_resid;
1804 int error;
1805 long size, xfersize, blkoffset;
1806
1807 vp = ap->a_vp;
1808 ip = VTOI(vp);
1809 uio = ap->a_uio;
1810 memset(&path, 0, sizeof(path));
1811
1812 orig_resid = uio->uio_resid;
1813 KASSERT(orig_resid >= 0, ("%s: uio->uio_resid < 0", __func__));
1814 if (orig_resid == 0)
1815 return (0);
1816 KASSERT(uio->uio_offset >= 0, ("%s: uio->uio_offset < 0", __func__));
1817 fs = ip->i_e2fs;
1818 if (uio->uio_offset < ip->i_size && uio->uio_offset >= fs->e2fs_maxfilesize)
1819 return (EOVERFLOW);
1820
1821 while (uio->uio_resid > 0) {
1822 if ((bytesinfile = ip->i_size - uio->uio_offset) <= 0)
1823 break;
1824 lbn = lblkno(fs, uio->uio_offset);
1825 size = blksize(fs, ip, lbn);
1826 blkoffset = blkoff(fs, uio->uio_offset);
1827
1828 xfersize = fs->e2fs_fsize - blkoffset;
1829 xfersize = MIN(xfersize, uio->uio_resid);
1830 xfersize = MIN(xfersize, bytesinfile);
1831
1832 /* get block from ext4 extent cache */
1833 cache_type = ext4_ext_in_cache(ip, lbn, &nex);
1834 switch (cache_type) {
1835 case EXT4_EXT_CACHE_NO:
1836 ext4_ext_find_extent(fs, ip, lbn, &path);
1837 ep = path.ep_ext;
1838 if (ep == NULL)
1839 return (EIO);
1840
1841 ext4_ext_put_cache(ip, ep, EXT4_EXT_CACHE_IN);
1842
1843 newblk = lbn - ep->e_blk + (ep->e_start_lo |
1844 (daddr_t)ep->e_start_hi << 32);
1845
1846 if (path.ep_bp != NULL) {
1847 brelse(path.ep_bp);
1848 path.ep_bp = NULL;
1849 }
1850 break;
1851
1852 case EXT4_EXT_CACHE_GAP:
1853 /* block has not been allocated yet */
1854 return (0);
1855
1856 case EXT4_EXT_CACHE_IN:
1857 newblk = lbn - nex.e_blk + (nex.e_start_lo |
1858 (daddr_t)nex.e_start_hi << 32);
1859 break;
1860
1861 default:
1862 panic("%s: invalid cache type", __func__);
1863 }
1864
1865 error = bread(ip->i_devvp, fsbtodb(fs, newblk), size, NOCRED, &bp);
1866 if (error) {
1867 brelse(bp);
1868 return (error);
1869 }
1870
1871 size -= bp->b_resid;
1872 if (size < xfersize) {
1873 if (size == 0) {
1874 bqrelse(bp);
1875 break;
1876 }
1877 xfersize = size;
1878 }
1879 error = uiomove(bp->b_data + blkoffset, (int)xfersize, uio);
1880 bqrelse(bp);
1881 if (error)
1882 return (error);
1883 }
1884
1885 return (0);
1886 }
1887
1888 /*
1889 * Vnode op for writing.
1890 */
1891 static int
1892 ext2_write(struct vop_write_args *ap)
1893 {
1894 struct vnode *vp;
1895 struct uio *uio;
1896 struct inode *ip;
1897 struct m_ext2fs *fs;
1898 struct buf *bp;
1899 daddr_t lbn;
1900 off_t osize;
1901 int blkoffset, error, flags, ioflag, resid, size, seqcount, xfersize;
1902
1903 ioflag = ap->a_ioflag;
1904 uio = ap->a_uio;
1905 vp = ap->a_vp;
1906
1907 seqcount = ioflag >> IO_SEQSHIFT;
1908 ip = VTOI(vp);
1909
1910 #ifdef INVARIANTS
1911 if (uio->uio_rw != UIO_WRITE)
1912 panic("%s: mode", "ext2_write");
1913 #endif
1914
1915 switch (vp->v_type) {
1916 case VREG:
1917 if (ioflag & IO_APPEND)
1918 uio->uio_offset = ip->i_size;
1919 if ((ip->i_flags & APPEND) && uio->uio_offset != ip->i_size)
1920 return (EPERM);
1921 /* FALLTHROUGH */
1922 case VLNK:
1923 break;
1924 case VDIR:
1925 /* XXX differs from ffs -- this is called from ext2_mkdir(). */
1926 if ((ioflag & IO_SYNC) == 0)
1927 panic("ext2_write: nonsync dir write");
1928 break;
1929 default:
1930 panic("ext2_write: type %p %d (%jd,%jd)", (void *)vp,
1931 vp->v_type, (intmax_t)uio->uio_offset,
1932 (intmax_t)uio->uio_resid);
1933 }
1934
1935 KASSERT(uio->uio_resid >= 0, ("ext2_write: uio->uio_resid < 0"));
1936 KASSERT(uio->uio_offset >= 0, ("ext2_write: uio->uio_offset < 0"));
1937 fs = ip->i_e2fs;
1938 if ((uoff_t)uio->uio_offset + uio->uio_resid > fs->e2fs_maxfilesize)
1939 return (EFBIG);
1940 /*
1941 * Maybe this should be above the vnode op call, but so long as
1942 * file servers have no limits, I don't think it matters.
1943 */
1944 if (vn_rlimit_fsize(vp, uio, uio->uio_td))
1945 return (EFBIG);
1946
1947 resid = uio->uio_resid;
1948 osize = ip->i_size;
1949 if (seqcount > BA_SEQMAX)
1950 flags = BA_SEQMAX << BA_SEQSHIFT;
1951 else
1952 flags = seqcount << BA_SEQSHIFT;
1953 if ((ioflag & IO_SYNC) && !DOINGASYNC(vp))
1954 flags |= IO_SYNC;
1955
1956 for (error = 0; uio->uio_resid > 0;) {
1957 lbn = lblkno(fs, uio->uio_offset);
1958 blkoffset = blkoff(fs, uio->uio_offset);
1959 xfersize = fs->e2fs_fsize - blkoffset;
1960 if (uio->uio_resid < xfersize)
1961 xfersize = uio->uio_resid;
1962 if (uio->uio_offset + xfersize > ip->i_size)
1963 vnode_pager_setsize(vp, uio->uio_offset + xfersize);
1964
1965 /*
1966 * We must perform a read-before-write if the transfer size
1967 * does not cover the entire buffer.
1968 */
1969 if (fs->e2fs_bsize > xfersize)
1970 flags |= BA_CLRBUF;
1971 else
1972 flags &= ~BA_CLRBUF;
1973 error = ext2_balloc(ip, lbn, blkoffset + xfersize,
1974 ap->a_cred, &bp, flags);
1975 if (error != 0)
1976 break;
1977
1978 if ((ioflag & (IO_SYNC|IO_INVAL)) == (IO_SYNC|IO_INVAL))
1979 bp->b_flags |= B_NOCACHE;
1980 if (uio->uio_offset + xfersize > ip->i_size)
1981 ip->i_size = uio->uio_offset + xfersize;
1982 size = blksize(fs, ip, lbn) - bp->b_resid;
1983 if (size < xfersize)
1984 xfersize = size;
1985
1986 error =
1987 uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
1988 /*
1989 * If the buffer is not already filled and we encounter an
1990 * error while trying to fill it, we have to clear out any
1991 * garbage data from the pages instantiated for the buffer.
1992 * If we do not, a failed uiomove() during a write can leave
1993 * the prior contents of the pages exposed to a userland mmap.
1994 *
1995 * Note that we need only clear buffers with a transfer size
1996 * equal to the block size because buffers with a shorter
1997 * transfer size were cleared above by the call to ext2_balloc()
1998 * with the BA_CLRBUF flag set.
1999 *
2000 * If the source region for uiomove identically mmaps the
2001 * buffer, uiomove() performed the NOP copy, and the buffer
2002 * content remains valid because the page fault handler
2003 * validated the pages.
2004 */
2005 if (error != 0 && (bp->b_flags & B_CACHE) == 0 &&
2006 fs->e2fs_bsize == xfersize)
2007 vfs_bio_clrbuf(bp);
2008 if (ioflag & (IO_VMIO|IO_DIRECT)) {
2009 bp->b_flags |= B_RELBUF;
2010 }
2011
2012 /*
2013 * If IO_SYNC each buffer is written synchronously. Otherwise
2014 * if we have a severe page deficiency write the buffer
2015 * asynchronously. Otherwise try to cluster, and if that
2016 * doesn't do it then either do an async write (if O_DIRECT),
2017 * or a delayed write (if not).
2018 */
2019 if (ioflag & IO_SYNC) {
2020 (void)bwrite(bp);
2021 } else if (vm_page_count_severe() ||
2022 buf_dirty_count_severe() ||
2023 (ioflag & IO_ASYNC)) {
2024 bp->b_flags |= B_CLUSTEROK;
2025 bawrite(bp);
2026 } else if (xfersize + blkoffset == fs->e2fs_fsize) {
2027 if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) {
2028 bp->b_flags |= B_CLUSTEROK;
2029 cluster_write(vp, bp, ip->i_size, seqcount, 0);
2030 } else {
2031 bawrite(bp);
2032 }
2033 } else if (ioflag & IO_DIRECT) {
2034 bp->b_flags |= B_CLUSTEROK;
2035 bawrite(bp);
2036 } else {
2037 bp->b_flags |= B_CLUSTEROK;
2038 bdwrite(bp);
2039 }
2040 if (error || xfersize == 0)
2041 break;
2042 }
2043 /*
2044 * If we successfully wrote any data, and we are not the superuser
2045 * we clear the setuid and setgid bits as a precaution against
2046 * tampering.
2047 */
2048 if ((ip->i_mode & (ISUID | ISGID)) && resid > uio->uio_resid &&
2049 ap->a_cred) {
2050 if (priv_check_cred(ap->a_cred, PRIV_VFS_RETAINSUGID, 0))
2051 ip->i_mode &= ~(ISUID | ISGID);
2052 }
2053 if (error) {
2054 if (ioflag & IO_UNIT) {
2055 (void)ext2_truncate(vp, osize,
2056 ioflag & IO_SYNC, ap->a_cred, uio->uio_td);
2057 uio->uio_offset -= resid - uio->uio_resid;
2058 uio->uio_resid = resid;
2059 }
2060 }
2061 if (uio->uio_resid != resid) {
2062 ip->i_flag |= IN_CHANGE | IN_UPDATE;
2063 if (ioflag & IO_SYNC)
2064 error = ext2_update(vp, 1);
2065 }
2066 return (error);
2067 }
2068
2069 /*
2070 * get page routine
2071 */
2072 static int
2073 ext2_getpages(struct vop_getpages_args *ap)
2074 {
2075 int i;
2076 vm_page_t mreq;
2077 int pcount;
2078
2079 pcount = round_page(ap->a_count) / PAGE_SIZE;
2080 mreq = ap->a_m[ap->a_reqpage];
2081
2082 /*
2083 * if ANY DEV_BSIZE blocks are valid on a large filesystem block,
2084 * then the entire page is valid. Since the page may be mapped,
2085 * user programs might reference data beyond the actual end of file
2086 * occuring within the page. We have to zero that data.
2087 */
2088 VM_OBJECT_WLOCK(mreq->object);
2089 if (mreq->valid) {
2090 if (mreq->valid != VM_PAGE_BITS_ALL)
2091 vm_page_zero_invalid(mreq, TRUE);
2092 for (i = 0; i < pcount; i++) {
2093 if (i != ap->a_reqpage) {
2094 vm_page_lock(ap->a_m[i]);
2095 vm_page_free(ap->a_m[i]);
2096 vm_page_unlock(ap->a_m[i]);
2097 }
2098 }
2099 VM_OBJECT_WUNLOCK(mreq->object);
2100 return VM_PAGER_OK;
2101 }
2102 VM_OBJECT_WUNLOCK(mreq->object);
2103
2104 return vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
2105 ap->a_count,
2106 ap->a_reqpage);
2107 }
Cache object: 25e76f4ddf16cf4f6b3046ad299b3da3
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