1 /*
2 * (MPSAFE)
3 *
4 * Copyright (c) 2009 The DragonFly Project. All rights reserved.
5 *
6 * This code is derived from software contributed to The DragonFly Project
7 * by Alex Hornung <ahornung@gmail.com>
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
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
17 * the documentation and/or other materials provided with the
18 * distribution.
19 * 3. Neither the name of The DragonFly Project nor the names of its
20 * contributors may be used to endorse or promote products derived
21 * from this software without specific, prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
27 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
29 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
31 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/time.h>
39 #include <sys/kernel.h>
40 #include <sys/lock.h>
41 #include <sys/fcntl.h>
42 #include <sys/proc.h>
43 #include <sys/caps.h>
44 #include <sys/signalvar.h>
45 #include <sys/vnode.h>
46 #include <sys/uio.h>
47 #include <sys/mount.h>
48 #include <sys/file.h>
49 #include <sys/dirent.h>
50 #include <sys/malloc.h>
51 #include <sys/stat.h>
52 #include <sys/reg.h>
53 #include <vm/vm_pager.h>
54 #include <vm/vm_zone.h>
55 #include <vm/vm_object.h>
56 #include <sys/filio.h>
57 #include <sys/ttycom.h>
58 #include <sys/tty.h>
59 #include <sys/diskslice.h>
60 #include <sys/sysctl.h>
61 #include <sys/devfs.h>
62 #include <sys/pioctl.h>
63 #include <vfs/fifofs/fifo.h>
64
65 #include <machine/limits.h>
66
67 #include <sys/buf2.h>
68 #include <vm/vm_page2.h>
69
70 #ifndef SPEC_CHAIN_DEBUG
71 #define SPEC_CHAIN_DEBUG 0
72 #endif
73
74 MALLOC_DECLARE(M_DEVFS);
75 #define DEVFS_BADOP (void *)devfs_vop_badop
76
77 static int devfs_vop_badop(struct vop_generic_args *);
78 static int devfs_vop_access(struct vop_access_args *);
79 static int devfs_vop_inactive(struct vop_inactive_args *);
80 static int devfs_vop_reclaim(struct vop_reclaim_args *);
81 static int devfs_vop_readdir(struct vop_readdir_args *);
82 static int devfs_vop_getattr(struct vop_getattr_args *);
83 static int devfs_vop_setattr(struct vop_setattr_args *);
84 static int devfs_vop_readlink(struct vop_readlink_args *);
85 static int devfs_vop_print(struct vop_print_args *);
86
87 static int devfs_vop_nresolve(struct vop_nresolve_args *);
88 static int devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args *);
89 static int devfs_vop_nmkdir(struct vop_nmkdir_args *);
90 static int devfs_vop_nsymlink(struct vop_nsymlink_args *);
91 static int devfs_vop_nrmdir(struct vop_nrmdir_args *);
92 static int devfs_vop_nremove(struct vop_nremove_args *);
93
94 static int devfs_spec_open(struct vop_open_args *);
95 static int devfs_spec_close(struct vop_close_args *);
96 static int devfs_spec_fsync(struct vop_fsync_args *);
97
98 static int devfs_spec_read(struct vop_read_args *);
99 static int devfs_spec_write(struct vop_write_args *);
100 static int devfs_spec_ioctl(struct vop_ioctl_args *);
101 static int devfs_spec_kqfilter(struct vop_kqfilter_args *);
102 static int devfs_spec_strategy(struct vop_strategy_args *);
103 static void devfs_spec_strategy_done(struct bio *);
104 static int devfs_spec_freeblks(struct vop_freeblks_args *);
105 static int devfs_spec_bmap(struct vop_bmap_args *);
106 static int devfs_spec_advlock(struct vop_advlock_args *);
107 static void devfs_spec_getpages_iodone(struct bio *);
108 static int devfs_spec_getpages(struct vop_getpages_args *);
109
110 static int devfs_fo_close(struct file *);
111 static int devfs_fo_read(struct file *, struct uio *, struct ucred *, int);
112 static int devfs_fo_write(struct file *, struct uio *, struct ucred *, int);
113 static int devfs_fo_stat(struct file *, struct stat *, struct ucred *);
114 static int devfs_fo_kqfilter(struct file *, struct knote *);
115 static int devfs_fo_ioctl(struct file *, u_long, caddr_t,
116 struct ucred *, struct sysmsg *);
117 static int devfs_fo_seek(struct file *, off_t, int, off_t *);
118 static __inline int sequential_heuristic(struct uio *, struct file *);
119
120 extern struct lock devfs_lock;
121
122 /*
123 * devfs vnode operations for regular files. All vnode ops are MPSAFE.
124 */
125 struct vop_ops devfs_vnode_norm_vops = {
126 .vop_default = vop_defaultop,
127 .vop_access = devfs_vop_access,
128 .vop_advlock = DEVFS_BADOP,
129 .vop_bmap = DEVFS_BADOP,
130 .vop_close = vop_stdclose,
131 .vop_getattr = devfs_vop_getattr,
132 .vop_inactive = devfs_vop_inactive,
133 .vop_ncreate = DEVFS_BADOP,
134 .vop_nresolve = devfs_vop_nresolve,
135 .vop_nlookupdotdot = devfs_vop_nlookupdotdot,
136 .vop_nlink = DEVFS_BADOP,
137 .vop_nmkdir = devfs_vop_nmkdir,
138 .vop_nmknod = DEVFS_BADOP,
139 .vop_nremove = devfs_vop_nremove,
140 .vop_nrename = DEVFS_BADOP,
141 .vop_nrmdir = devfs_vop_nrmdir,
142 .vop_nsymlink = devfs_vop_nsymlink,
143 .vop_open = vop_stdopen,
144 .vop_pathconf = vop_stdpathconf,
145 .vop_print = devfs_vop_print,
146 .vop_read = DEVFS_BADOP,
147 .vop_readdir = devfs_vop_readdir,
148 .vop_readlink = devfs_vop_readlink,
149 .vop_reallocblks = DEVFS_BADOP,
150 .vop_reclaim = devfs_vop_reclaim,
151 .vop_setattr = devfs_vop_setattr,
152 .vop_write = DEVFS_BADOP,
153 .vop_ioctl = DEVFS_BADOP
154 };
155
156 /*
157 * devfs vnode operations for character devices. All vnode ops are MPSAFE.
158 */
159 struct vop_ops devfs_vnode_dev_vops = {
160 .vop_default = vop_defaultop,
161 .vop_access = devfs_vop_access,
162 .vop_advlock = devfs_spec_advlock,
163 .vop_bmap = devfs_spec_bmap,
164 .vop_close = devfs_spec_close,
165 .vop_freeblks = devfs_spec_freeblks,
166 .vop_fsync = devfs_spec_fsync,
167 .vop_getattr = devfs_vop_getattr,
168 .vop_getpages = devfs_spec_getpages,
169 .vop_inactive = devfs_vop_inactive,
170 .vop_open = devfs_spec_open,
171 .vop_pathconf = vop_stdpathconf,
172 .vop_print = devfs_vop_print,
173 .vop_kqfilter = devfs_spec_kqfilter,
174 .vop_read = devfs_spec_read,
175 .vop_readdir = DEVFS_BADOP,
176 .vop_readlink = DEVFS_BADOP,
177 .vop_reallocblks = DEVFS_BADOP,
178 .vop_reclaim = devfs_vop_reclaim,
179 .vop_setattr = devfs_vop_setattr,
180 .vop_strategy = devfs_spec_strategy,
181 .vop_write = devfs_spec_write,
182 .vop_ioctl = devfs_spec_ioctl
183 };
184
185 /*
186 * devfs file pointer operations. All fileops are MPSAFE.
187 */
188 struct vop_ops *devfs_vnode_dev_vops_p = &devfs_vnode_dev_vops;
189
190 struct fileops devfs_dev_fileops = {
191 .fo_read = devfs_fo_read,
192 .fo_write = devfs_fo_write,
193 .fo_ioctl = devfs_fo_ioctl,
194 .fo_kqfilter = devfs_fo_kqfilter,
195 .fo_stat = devfs_fo_stat,
196 .fo_close = devfs_fo_close,
197 .fo_shutdown = nofo_shutdown,
198 .fo_seek = devfs_fo_seek
199 };
200
201 /*
202 * These two functions are possibly temporary hacks for devices (aka
203 * the pty code) which want to control the node attributes themselves.
204 *
205 * XXX we may ultimately desire to simply remove the uid/gid/mode
206 * from the node entirely.
207 *
208 * MPSAFE - sorta. Theoretically the overwrite can compete since they
209 * are loading from the same fields.
210 */
211 static __inline void
node_sync_dev_get(struct devfs_node * node)212 node_sync_dev_get(struct devfs_node *node)
213 {
214 cdev_t dev;
215
216 if ((dev = node->d_dev) && (dev->si_flags & SI_OVERRIDE)) {
217 node->uid = dev->si_uid;
218 node->gid = dev->si_gid;
219 node->mode = dev->si_perms;
220 }
221 }
222
223 static __inline void
node_sync_dev_set(struct devfs_node * node)224 node_sync_dev_set(struct devfs_node *node)
225 {
226 cdev_t dev;
227
228 if ((dev = node->d_dev) && (dev->si_flags & SI_OVERRIDE)) {
229 dev->si_uid = node->uid;
230 dev->si_gid = node->gid;
231 dev->si_perms = node->mode;
232 }
233 }
234
235 /*
236 * generic entry point for unsupported operations
237 */
238 static int
devfs_vop_badop(struct vop_generic_args * ap)239 devfs_vop_badop(struct vop_generic_args *ap)
240 {
241 return (EIO);
242 }
243
244
245 static int
devfs_vop_access(struct vop_access_args * ap)246 devfs_vop_access(struct vop_access_args *ap)
247 {
248 struct devfs_node *node = DEVFS_NODE(ap->a_vp);
249 int error;
250
251 if (!devfs_node_is_accessible(node))
252 return ENOENT;
253 node_sync_dev_get(node);
254 error = vop_helper_access(ap, node->uid, node->gid,
255 node->mode, node->flags);
256
257 return error;
258 }
259
260
261 static int
devfs_vop_inactive(struct vop_inactive_args * ap)262 devfs_vop_inactive(struct vop_inactive_args *ap)
263 {
264 struct devfs_node *node = DEVFS_NODE(ap->a_vp);
265
266 if (node == NULL || (node->flags & DEVFS_NODE_LINKED) == 0)
267 vrecycle(ap->a_vp);
268 return 0;
269 }
270
271
272 static int
devfs_vop_reclaim(struct vop_reclaim_args * ap)273 devfs_vop_reclaim(struct vop_reclaim_args *ap)
274 {
275 struct devfs_node *node;
276 struct vnode *vp;
277 int locked;
278
279 /*
280 * Check if it is locked already. if not, we acquire the devfs lock
281 */
282 if ((lockstatus(&devfs_lock, curthread)) != LK_EXCLUSIVE) {
283 lockmgr(&devfs_lock, LK_EXCLUSIVE);
284 locked = 1;
285 } else {
286 locked = 0;
287 }
288
289 /*
290 * Get rid of the devfs_node if it is no longer linked into the
291 * topology. Interlocked by devfs_lock. However, be careful
292 * interposing other operations between cleaning out v_data and
293 * devfs_freep() as the node is only protected by devfs_lock
294 * once the vnode is disassociated.
295 */
296 vp = ap->a_vp;
297 node = DEVFS_NODE(vp);
298
299 if (node) {
300 if (node->v_node != vp) {
301 kprintf("NODE->V_NODE MISMATCH VP=%p NODEVP=%p\n",
302 vp, node->v_node);
303 }
304 vp->v_data = NULL;
305 node->v_node = NULL;
306 if ((node->flags & DEVFS_NODE_LINKED) == 0)
307 devfs_freep(node);
308 }
309 v_release_rdev(vp);
310
311 if (locked)
312 lockmgr(&devfs_lock, LK_RELEASE);
313
314 /*
315 * v_rdev needs to be properly released using v_release_rdev
316 * Make sure v_data is NULL as well.
317 */
318 return 0;
319 }
320
321
322 static int
devfs_vop_readdir(struct vop_readdir_args * ap)323 devfs_vop_readdir(struct vop_readdir_args *ap)
324 {
325 struct devfs_node *dnode = DEVFS_NODE(ap->a_vp);
326 struct devfs_node *node;
327 int cookie_index;
328 int ncookies;
329 int error2;
330 int error;
331 int r;
332 off_t *cookies;
333 off_t saveoff;
334
335 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_readdir() called!\n");
336
337 if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX)
338 return (EINVAL);
339 error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY | LK_FAILRECLAIM);
340 if (error)
341 return (error);
342
343 if (!devfs_node_is_accessible(dnode)) {
344 vn_unlock(ap->a_vp);
345 return ENOENT;
346 }
347
348 lockmgr(&devfs_lock, LK_EXCLUSIVE);
349
350 saveoff = ap->a_uio->uio_offset;
351
352 if (ap->a_ncookies) {
353 ncookies = ap->a_uio->uio_resid / 16 + 1; /* Why / 16 ?? */
354 if (ncookies > 256)
355 ncookies = 256;
356 cookies = kmalloc(256 * sizeof(off_t), M_TEMP, M_WAITOK);
357 cookie_index = 0;
358 } else {
359 ncookies = -1;
360 cookies = NULL;
361 cookie_index = 0;
362 }
363
364 vfs_timestamp(&dnode->atime);
365
366 if (saveoff == 0) {
367 r = vop_write_dirent(&error, ap->a_uio, dnode->d_dir.d_ino,
368 DT_DIR, 1, ".");
369 if (r)
370 goto done;
371 if (cookies)
372 cookies[cookie_index] = saveoff;
373 saveoff++;
374 cookie_index++;
375 if (cookie_index == ncookies)
376 goto done;
377 }
378
379 if (saveoff == 1) {
380 if (dnode->parent) {
381 r = vop_write_dirent(&error, ap->a_uio,
382 dnode->parent->d_dir.d_ino,
383 DT_DIR, 2, "..");
384 } else {
385 r = vop_write_dirent(&error, ap->a_uio,
386 dnode->d_dir.d_ino,
387 DT_DIR, 2, "..");
388 }
389 if (r)
390 goto done;
391 if (cookies)
392 cookies[cookie_index] = saveoff;
393 saveoff++;
394 cookie_index++;
395 if (cookie_index == ncookies)
396 goto done;
397 }
398
399 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) {
400 if ((node->flags & DEVFS_HIDDEN) ||
401 (node->flags & DEVFS_INVISIBLE)) {
402 continue;
403 }
404
405 /*
406 * If the node type is a valid devfs alias, then we make
407 * sure that the target isn't hidden. If it is, we don't
408 * show the link in the directory listing.
409 */
410 if ((node->node_type == Nlink) && (node->link_target != NULL) &&
411 (node->link_target->flags & DEVFS_HIDDEN))
412 continue;
413
414 if (node->cookie < saveoff)
415 continue;
416
417 saveoff = node->cookie;
418
419 error2 = vop_write_dirent(&error, ap->a_uio, node->d_dir.d_ino,
420 node->d_dir.d_type,
421 node->d_dir.d_namlen,
422 node->d_dir.d_name);
423
424 if (error2)
425 break;
426
427 saveoff++;
428
429 if (cookies)
430 cookies[cookie_index] = node->cookie;
431 ++cookie_index;
432 if (cookie_index == ncookies)
433 break;
434 }
435
436 done:
437 lockmgr(&devfs_lock, LK_RELEASE);
438 vn_unlock(ap->a_vp);
439
440 ap->a_uio->uio_offset = saveoff;
441 if (error && cookie_index == 0) {
442 if (cookies) {
443 kfree(cookies, M_TEMP);
444 *ap->a_ncookies = 0;
445 *ap->a_cookies = NULL;
446 }
447 } else {
448 if (cookies) {
449 *ap->a_ncookies = cookie_index;
450 *ap->a_cookies = cookies;
451 }
452 }
453 return (error);
454 }
455
456
457 static int
devfs_vop_nresolve(struct vop_nresolve_args * ap)458 devfs_vop_nresolve(struct vop_nresolve_args *ap)
459 {
460 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp);
461 struct devfs_node *node, *found = NULL;
462 struct namecache *ncp;
463 struct vnode *vp = NULL;
464 int error = 0;
465 int len;
466 int depth;
467
468 ncp = ap->a_nch->ncp;
469 len = ncp->nc_nlen;
470
471 if (!devfs_node_is_accessible(dnode))
472 return ENOENT;
473
474 lockmgr(&devfs_lock, LK_EXCLUSIVE);
475
476 if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir)) {
477 error = ENOENT;
478 cache_setvp(ap->a_nch, NULL);
479 goto out;
480 }
481
482 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) {
483 if (len == node->d_dir.d_namlen) {
484 if (!memcmp(ncp->nc_name, node->d_dir.d_name, len)) {
485 found = node;
486 break;
487 }
488 }
489 }
490
491 if (found) {
492 depth = 0;
493 while ((found->node_type == Nlink) && (found->link_target)) {
494 if (depth >= 8) {
495 devfs_debug(DEVFS_DEBUG_SHOW, "Recursive link or depth >= 8");
496 break;
497 }
498
499 found = found->link_target;
500 ++depth;
501 }
502
503 if (!(found->flags & DEVFS_HIDDEN))
504 devfs_allocv(/*ap->a_dvp->v_mount, */ &vp, found);
505 }
506
507 if (vp == NULL) {
508 error = ENOENT;
509 cache_setvp(ap->a_nch, NULL);
510 goto out;
511
512 }
513 KKASSERT(vp);
514 vn_unlock(vp);
515 cache_setvp(ap->a_nch, vp);
516 vrele(vp);
517 out:
518 lockmgr(&devfs_lock, LK_RELEASE);
519
520 return error;
521 }
522
523
524 static int
devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args * ap)525 devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args *ap)
526 {
527 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp);
528
529 *ap->a_vpp = NULL;
530 if (!devfs_node_is_accessible(dnode))
531 return ENOENT;
532
533 lockmgr(&devfs_lock, LK_EXCLUSIVE);
534 if (dnode->parent != NULL) {
535 devfs_allocv(ap->a_vpp, dnode->parent);
536 vn_unlock(*ap->a_vpp);
537 }
538 lockmgr(&devfs_lock, LK_RELEASE);
539
540 return ((*ap->a_vpp == NULL) ? ENOENT : 0);
541 }
542
543
544 /*
545 * getattr() - Does not need a lock since the vp is refd
546 */
547 static int
devfs_vop_getattr(struct vop_getattr_args * ap)548 devfs_vop_getattr(struct vop_getattr_args *ap)
549 {
550 struct devfs_node *node = DEVFS_NODE(ap->a_vp);
551 struct vattr *vap = ap->a_vap;
552 struct partinfo pinfo;
553 int error = 0;
554
555 #if 0
556 if (!devfs_node_is_accessible(node))
557 return ENOENT;
558 #endif
559
560 /*
561 * XXX This is a temporary hack to prevent crashes when the device is
562 * being destroyed (and so the underlying node will be gone) while
563 * a userland program is blocked in a read().
564 */
565 if (node == NULL)
566 return EIO;
567
568 node_sync_dev_get(node);
569
570 /* start by zeroing out the attributes */
571 VATTR_NULL(vap);
572
573 /* next do all the common fields */
574 vap->va_type = ap->a_vp->v_type;
575 vap->va_mode = node->mode;
576 vap->va_fileid = DEVFS_NODE(ap->a_vp)->d_dir.d_ino ;
577 vap->va_flags = 0;
578 vap->va_blocksize = DEV_BSIZE;
579 vap->va_bytes = vap->va_size = 0;
580
581 vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0];
582
583 vap->va_atime = node->atime;
584 vap->va_mtime = node->mtime;
585 vap->va_ctime = node->ctime;
586
587 vap->va_nlink = 1; /* number of references to file */
588
589 vap->va_uid = node->uid;
590 vap->va_gid = node->gid;
591
592 vap->va_rmajor = 0;
593 vap->va_rminor = 0;
594
595 if ((node->node_type == Ndev) && node->d_dev) {
596 reference_dev(node->d_dev);
597 vap->va_rminor = node->d_dev->si_uminor;
598 release_dev(node->d_dev);
599 }
600
601 /* For a softlink the va_size is the length of the softlink */
602 if (node->symlink_name != 0) {
603 vap->va_bytes = vap->va_size = node->symlink_namelen;
604 }
605
606 /*
607 * For a disk-type device, va_size is the size of the underlying
608 * device, so that lseek() works properly.
609 */
610 if ((node->d_dev) && (dev_dflags(node->d_dev) & D_DISK)) {
611 bzero(&pinfo, sizeof(pinfo));
612 error = dev_dioctl(node->d_dev, DIOCGPART, (void *)&pinfo,
613 0, proc0.p_ucred, NULL, NULL);
614 if ((error == 0) && (pinfo.media_blksize != 0)) {
615 vap->va_size = pinfo.media_size;
616 } else {
617 vap->va_size = 0;
618 error = 0;
619 }
620 }
621
622 return (error);
623 }
624
625 static int
devfs_vop_setattr(struct vop_setattr_args * ap)626 devfs_vop_setattr(struct vop_setattr_args *ap)
627 {
628 struct devfs_node *node = DEVFS_NODE(ap->a_vp);
629 struct vattr *vap;
630 uid_t cur_uid;
631 gid_t cur_gid;
632 mode_t cur_mode;
633 int error = 0;
634
635 if (!devfs_node_is_accessible(node))
636 return ENOENT;
637 node_sync_dev_get(node);
638
639 vap = ap->a_vap;
640
641 if ((vap->va_uid != (uid_t)VNOVAL) || (vap->va_gid != (gid_t)VNOVAL)) {
642 cur_uid = node->uid;
643 cur_gid = node->gid;
644 cur_mode = node->mode;
645 error = vop_helper_chown(ap->a_vp, vap->va_uid, vap->va_gid,
646 ap->a_cred, &cur_uid, &cur_gid, &cur_mode);
647 if (error)
648 goto out;
649
650 if (node->uid != cur_uid || node->gid != cur_gid) {
651 node->uid = cur_uid;
652 node->gid = cur_gid;
653 node->mode = cur_mode;
654 }
655 }
656
657 if (vap->va_mode != (mode_t)VNOVAL) {
658 cur_mode = node->mode;
659 error = vop_helper_chmod(ap->a_vp, vap->va_mode, ap->a_cred,
660 node->uid, node->gid, &cur_mode);
661 if (error == 0 && node->mode != cur_mode) {
662 node->mode = cur_mode;
663 }
664 }
665
666 out:
667 node_sync_dev_set(node);
668 vfs_timestamp(&node->ctime);
669
670 return error;
671 }
672
673
674 static int
devfs_vop_readlink(struct vop_readlink_args * ap)675 devfs_vop_readlink(struct vop_readlink_args *ap)
676 {
677 struct devfs_node *node = DEVFS_NODE(ap->a_vp);
678 int ret;
679
680 if (!devfs_node_is_accessible(node))
681 return ENOENT;
682
683 lockmgr(&devfs_lock, LK_SHARED);
684 ret = uiomove(node->symlink_name, node->symlink_namelen, ap->a_uio);
685 lockmgr(&devfs_lock, LK_RELEASE);
686
687 return ret;
688 }
689
690
691 static int
devfs_vop_print(struct vop_print_args * ap)692 devfs_vop_print(struct vop_print_args *ap)
693 {
694 return (0);
695 }
696
697 static int
devfs_vop_nmkdir(struct vop_nmkdir_args * ap)698 devfs_vop_nmkdir(struct vop_nmkdir_args *ap)
699 {
700 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp);
701 struct devfs_node *node;
702
703 if (!devfs_node_is_accessible(dnode))
704 return ENOENT;
705
706 if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir))
707 goto out;
708
709 lockmgr(&devfs_lock, LK_EXCLUSIVE);
710 devfs_allocvp(ap->a_dvp->v_mount, ap->a_vpp, Ndir,
711 ap->a_nch->ncp->nc_name, dnode, NULL);
712
713 if (*ap->a_vpp) {
714 node = DEVFS_NODE(*ap->a_vpp);
715 node->flags |= DEVFS_USER_CREATED;
716 cache_setunresolved(ap->a_nch);
717 cache_setvp(ap->a_nch, *ap->a_vpp);
718 }
719 lockmgr(&devfs_lock, LK_RELEASE);
720 out:
721 return ((*ap->a_vpp == NULL) ? ENOTDIR : 0);
722 }
723
724 static int
devfs_vop_nsymlink(struct vop_nsymlink_args * ap)725 devfs_vop_nsymlink(struct vop_nsymlink_args *ap)
726 {
727 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp);
728 struct devfs_node *node;
729 size_t targetlen;
730
731 if (!devfs_node_is_accessible(dnode))
732 return ENOENT;
733
734 ap->a_vap->va_type = VLNK;
735
736 if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir))
737 goto out;
738
739 lockmgr(&devfs_lock, LK_EXCLUSIVE);
740 devfs_allocvp(ap->a_dvp->v_mount, ap->a_vpp, Nlink,
741 ap->a_nch->ncp->nc_name, dnode, NULL);
742
743 targetlen = strlen(ap->a_target);
744 if (*ap->a_vpp) {
745 node = DEVFS_NODE(*ap->a_vpp);
746 node->flags |= DEVFS_USER_CREATED;
747 node->symlink_namelen = targetlen;
748 node->symlink_name = kmalloc(targetlen + 1, M_DEVFS, M_WAITOK);
749 memcpy(node->symlink_name, ap->a_target, targetlen);
750 node->symlink_name[targetlen] = '\0';
751 cache_setunresolved(ap->a_nch);
752 cache_setvp(ap->a_nch, *ap->a_vpp);
753 }
754 lockmgr(&devfs_lock, LK_RELEASE);
755 out:
756 return ((*ap->a_vpp == NULL) ? ENOTDIR : 0);
757 }
758
759 static int
devfs_vop_nrmdir(struct vop_nrmdir_args * ap)760 devfs_vop_nrmdir(struct vop_nrmdir_args *ap)
761 {
762 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp);
763 struct devfs_node *node;
764 struct namecache *ncp;
765 int error = ENOENT;
766
767 ncp = ap->a_nch->ncp;
768
769 if (!devfs_node_is_accessible(dnode))
770 return ENOENT;
771
772 lockmgr(&devfs_lock, LK_EXCLUSIVE);
773
774 if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir))
775 goto out;
776
777 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) {
778 if (ncp->nc_nlen != node->d_dir.d_namlen)
779 continue;
780 if (memcmp(ncp->nc_name, node->d_dir.d_name, ncp->nc_nlen))
781 continue;
782
783 /*
784 * only allow removal of user created dirs
785 */
786 if ((node->flags & DEVFS_USER_CREATED) == 0) {
787 error = EPERM;
788 goto out;
789 } else if (node->node_type != Ndir) {
790 error = ENOTDIR;
791 goto out;
792 } else if (node->nchildren > 2) {
793 error = ENOTEMPTY;
794 goto out;
795 } else {
796 if (node->v_node)
797 cache_inval_vp(node->v_node, CINV_DESTROY);
798 devfs_unlinkp(node);
799 error = 0;
800 break;
801 }
802 }
803
804 cache_unlink(ap->a_nch);
805 out:
806 lockmgr(&devfs_lock, LK_RELEASE);
807 return error;
808 }
809
810 static int
devfs_vop_nremove(struct vop_nremove_args * ap)811 devfs_vop_nremove(struct vop_nremove_args *ap)
812 {
813 struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp);
814 struct devfs_node *node;
815 struct namecache *ncp;
816 int error = ENOENT;
817
818 ncp = ap->a_nch->ncp;
819
820 if (!devfs_node_is_accessible(dnode))
821 return ENOENT;
822
823 lockmgr(&devfs_lock, LK_EXCLUSIVE);
824
825 if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir))
826 goto out;
827
828 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) {
829 if (ncp->nc_nlen != node->d_dir.d_namlen)
830 continue;
831 if (memcmp(ncp->nc_name, node->d_dir.d_name, ncp->nc_nlen))
832 continue;
833
834 /*
835 * only allow removal of user created stuff (e.g. symlinks)
836 */
837 if ((node->flags & DEVFS_USER_CREATED) == 0) {
838 error = EPERM;
839 goto out;
840 } else if (node->node_type == Ndir) {
841 error = EISDIR;
842 goto out;
843 } else {
844 if (node->v_node)
845 cache_inval_vp(node->v_node, CINV_DESTROY);
846 devfs_unlinkp(node);
847 error = 0;
848 break;
849 }
850 }
851
852 cache_unlink(ap->a_nch);
853 out:
854 lockmgr(&devfs_lock, LK_RELEASE);
855 return error;
856 }
857
858
859 static int
devfs_spec_open(struct vop_open_args * ap)860 devfs_spec_open(struct vop_open_args *ap)
861 {
862 struct vnode *vp = ap->a_vp;
863 struct vnode *orig_vp = NULL;
864 struct devfs_node *node = DEVFS_NODE(vp);
865 struct devfs_node *newnode;
866 cdev_t dev, ndev = NULL;
867 int error = 0;
868
869 if (node) {
870 if (node->d_dev == NULL)
871 return ENXIO;
872 if (!devfs_node_is_accessible(node))
873 return ENOENT;
874 }
875
876 if ((dev = vp->v_rdev) == NULL)
877 return ENXIO;
878
879 /*
880 * Simple devices that don't care. Retain the shared lock.
881 */
882 if (dev_dflags(dev) & D_QUICK) {
883 vn_unlock(vp);
884 error = dev_dopen(dev, ap->a_mode, S_IFCHR,
885 ap->a_cred, ap->a_fpp, vp);
886 vn_lock(vp, LK_SHARED | LK_RETRY);
887 if (error)
888 return error;
889 vop_stdopen(ap);
890 goto skip;
891 }
892
893 /*
894 * Slow code
895 */
896 vn_lock(vp, LK_UPGRADE | LK_RETRY);
897 if (node && ap->a_fpp) {
898 int exists;
899
900 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_open: -1.1-\n");
901 lockmgr(&devfs_lock, LK_SHARED);
902
903 ndev = devfs_clone(dev, node->d_dir.d_name,
904 node->d_dir.d_namlen,
905 ap->a_mode, ap->a_cred);
906 if (ndev != NULL) {
907 lockmgr(&devfs_lock, LK_RELEASE);
908 lockmgr(&devfs_lock, LK_EXCLUSIVE);
909 newnode = devfs_create_device_node(
910 DEVFS_MNTDATA(vp->v_mount)->root_node,
911 ndev, &exists, NULL, NULL);
912 /* XXX: possibly destroy device if this happens */
913
914 if (newnode != NULL) {
915 dev = ndev;
916 if (exists == 0)
917 devfs_link_dev(dev);
918
919 devfs_debug(DEVFS_DEBUG_DEBUG,
920 "parent here is: %s, node is: |%s|\n",
921 ((node->parent->node_type == Nroot) ?
922 "ROOT!" : node->parent->d_dir.d_name),
923 newnode->d_dir.d_name);
924 devfs_debug(DEVFS_DEBUG_DEBUG,
925 "test: %s\n",
926 ((struct devfs_node *)(TAILQ_LAST(DEVFS_DENODE_HEAD(node->parent), devfs_node_head)))->d_dir.d_name);
927
928 /*
929 * orig_vp is set to the original vp if we
930 * cloned.
931 */
932 /* node->flags |= DEVFS_CLONED; */
933 devfs_allocv(&vp, newnode);
934 orig_vp = ap->a_vp;
935 ap->a_vp = vp;
936 }
937 }
938 lockmgr(&devfs_lock, LK_RELEASE);
939
940 /*
941 * Synchronize devfs here to make sure that, if the cloned
942 * device creates other device nodes in addition to the
943 * cloned one, all of them are created by the time we return
944 * from opening the cloned one.
945 */
946 if (ndev)
947 devfs_config();
948 }
949
950 devfs_debug(DEVFS_DEBUG_DEBUG,
951 "devfs_spec_open() called on %s! \n",
952 dev->si_name);
953
954 /*
955 * Make this field valid before any I/O in ->d_open
956 *
957 * NOTE: Shared vnode lock probably held, but its ok as long
958 * as assignments are consistent.
959 */
960 if (!dev->si_iosize_max)
961 /* XXX: old DFLTPHYS == 64KB dependency */
962 dev->si_iosize_max = min(MAXPHYS,64*1024);
963
964 if (dev_dflags(dev) & D_TTY)
965 vsetflags(vp, VISTTY);
966
967 /*
968 * Open the underlying device.
969 *
970 * NOTE: If the dev open returns EALREADY it has completed the open
971 * operation and is returning a fully initialized *a->a_fpp
972 * (which it may also have replaced). This includes issuing
973 * any necessary VOP_OPEN().
974 *
975 * Also, the returned ap->a_fpp might not be DTYPE_VNODE and
976 * if it is might not be using the vp we supplied to it.
977 */
978 vn_unlock(vp);
979 error = dev_dopen(dev, ap->a_mode, S_IFCHR,
980 ap->a_cred, ap->a_fpp, vp);
981 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
982
983 if (__predict_false(error == EALREADY)) {
984 if (orig_vp)
985 vput(vp);
986 return 0;
987 }
988
989 /*
990 * Clean up any cloned vp if we error out.
991 */
992 if (__predict_false(error != 0)) {
993 if (orig_vp) {
994 vput(vp);
995 ap->a_vp = orig_vp;
996 /* orig_vp = NULL; */
997 }
998 return error;
999 }
1000
1001 /*
1002 * This checks if the disk device is going to be opened for writing.
1003 * It will be only allowed in the cases where securelevel permits it
1004 * and it's not mounted R/W.
1005 */
1006 if ((dev_dflags(dev) & D_DISK) && (ap->a_mode & FWRITE) &&
1007 (ap->a_cred != FSCRED)) {
1008
1009 /* Very secure mode. No open for writing allowed */
1010 if (securelevel >= 2)
1011 return EPERM;
1012
1013 /*
1014 * If it is mounted R/W, do not allow to open for writing.
1015 * In the case it's mounted read-only but securelevel
1016 * is >= 1, then do not allow opening for writing either.
1017 */
1018 if (vfs_mountedon(vp)) {
1019 if (!(dev->si_mountpoint->mnt_flag & MNT_RDONLY))
1020 return EBUSY;
1021 else if (securelevel >= 1)
1022 return EPERM;
1023 }
1024 }
1025
1026 /*
1027 * NOTE: vnode is still locked shared. t_stop assignment should
1028 * remain consistent so we should be ok.
1029 */
1030 if (dev_dflags(dev) & D_TTY) {
1031 if (dev->si_tty) {
1032 struct tty *tp;
1033 tp = dev->si_tty;
1034 if (!tp->t_stop) {
1035 devfs_debug(DEVFS_DEBUG_DEBUG,
1036 "devfs: no t_stop\n");
1037 tp->t_stop = nottystop;
1038 }
1039 }
1040 }
1041
1042 /*
1043 * NOTE: vnode is still locked shared. assignments should
1044 * remain consistent so we should be ok. However,
1045 * upgrade to exclusive if we need a VM object.
1046 */
1047 if (vn_isdisk(vp, NULL)) {
1048 if (!dev->si_bsize_phys)
1049 dev->si_bsize_phys = DEV_BSIZE;
1050 vinitvmio(vp, IDX_TO_OFF(INT_MAX), PAGE_SIZE, -1);
1051 }
1052
1053 vop_stdopen(ap);
1054 #if 0
1055 if (node)
1056 vfs_timestamp(&node->atime);
1057 #endif
1058 /*
1059 * If we replaced the vp the vop_stdopen() call will have loaded
1060 * it into fp->f_data and vref()d the vp, giving us two refs. So
1061 * instead of just unlocking it here we have to vput() it.
1062 */
1063 if (orig_vp)
1064 vput(vp);
1065
1066 /* Ugly pty magic, to make pty devices appear once they are opened */
1067 if (node && (node->flags & DEVFS_PTY) == DEVFS_PTY) {
1068 if (node->flags & DEVFS_INVISIBLE)
1069 node->flags &= ~DEVFS_INVISIBLE;
1070 }
1071
1072 skip:
1073 if (ap->a_fpp) {
1074 struct file *fp = *ap->a_fpp;
1075
1076 KKASSERT(fp->f_type == DTYPE_VNODE);
1077 KKASSERT((fp->f_flag & FMASK) == (ap->a_mode & FMASK));
1078 fp->f_ops = &devfs_dev_fileops;
1079 KKASSERT(fp->f_data == (void *)vp);
1080 }
1081
1082 return 0;
1083 }
1084
1085 static int
devfs_spec_close(struct vop_close_args * ap)1086 devfs_spec_close(struct vop_close_args *ap)
1087 {
1088 struct devfs_node *node;
1089 struct proc *p = curproc;
1090 struct vnode *vp = ap->a_vp;
1091 cdev_t dev = vp->v_rdev;
1092 int error = 0;
1093 int needrelock;
1094 int opencount;
1095
1096 /*
1097 * Devices flagged D_QUICK require no special handling.
1098 */
1099 if (dev && dev_dflags(dev) & D_QUICK) {
1100 opencount = vp->v_opencount;
1101 if (opencount <= 1)
1102 opencount = count_dev(dev); /* XXX NOT SMP SAFE */
1103 if (((vp->v_flag & VRECLAIMED) ||
1104 (dev_dflags(dev) & D_TRACKCLOSE) ||
1105 (opencount == 1))) {
1106 vn_unlock(vp);
1107 error = dev_dclose(dev, ap->a_fflag, S_IFCHR, ap->a_fp);
1108 vn_lock(vp, LK_SHARED | LK_RETRY);
1109 }
1110 goto skip;
1111 }
1112
1113 /*
1114 * We do special tests on the opencount so unfortunately we need
1115 * an exclusive lock.
1116 */
1117 vn_lock(vp, LK_UPGRADE | LK_RETRY);
1118
1119 if (dev)
1120 devfs_debug(DEVFS_DEBUG_DEBUG,
1121 "devfs_spec_close() called on %s! \n",
1122 dev->si_name);
1123 else
1124 devfs_debug(DEVFS_DEBUG_DEBUG,
1125 "devfs_spec_close() called, null vode!\n");
1126
1127 /*
1128 * A couple of hacks for devices and tty devices. The
1129 * vnode ref count cannot be used to figure out the
1130 * last close, but we can use v_opencount now that
1131 * revoke works properly.
1132 *
1133 * Detect the last close on a controlling terminal and clear
1134 * the session (half-close).
1135 *
1136 * XXX opencount is not SMP safe. The vnode is locked but there
1137 * may be multiple vnodes referencing the same device.
1138 */
1139 if (dev) {
1140 /*
1141 * NOTE: Try to avoid global tokens when testing opencount
1142 * XXX hack, fixme. needs a struct lock and opencount in
1143 * struct cdev itself.
1144 */
1145 reference_dev(dev);
1146 opencount = vp->v_opencount;
1147 if (opencount <= 1)
1148 opencount = count_dev(dev); /* XXX NOT SMP SAFE */
1149 } else {
1150 opencount = 0;
1151 }
1152
1153 if (p && vp->v_opencount <= 1 && vp == p->p_session->s_ttyvp) {
1154 p->p_session->s_ttyvp = NULL;
1155 vrele(vp);
1156 }
1157
1158 /*
1159 * Vnodes can be opened and closed multiple times. Do not really
1160 * close the device unless (1) it is being closed forcibly,
1161 * (2) the device wants to track closes, or (3) this is the last
1162 * vnode doing its last close on the device.
1163 *
1164 * XXX the VXLOCK (force close) case can leave vnodes referencing
1165 * a closed device. This might not occur now that our revoke is
1166 * fixed.
1167 */
1168 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() -1- \n");
1169 if (dev && ((vp->v_flag & VRECLAIMED) ||
1170 (dev_dflags(dev) & D_TRACKCLOSE) ||
1171 (opencount == 1))) {
1172 /*
1173 * Ugly pty magic, to make pty devices disappear again once
1174 * they are closed.
1175 */
1176 node = DEVFS_NODE(ap->a_vp);
1177 if (node && (node->flags & DEVFS_PTY))
1178 node->flags |= DEVFS_INVISIBLE;
1179
1180 /*
1181 * Unlock around dev_dclose(), unless the vnode is
1182 * undergoing a vgone/reclaim (during umount).
1183 */
1184 needrelock = 0;
1185 if ((vp->v_flag & VRECLAIMED) == 0 && vn_islocked(vp)) {
1186 needrelock = 1;
1187 vn_unlock(vp);
1188 }
1189
1190 /*
1191 * WARNING! If the device destroys itself the devfs node
1192 * can disappear here.
1193 *
1194 * WARNING! vn_lock() will fail if the vp is in a VRECLAIM,
1195 * which can occur during umount.
1196 */
1197 error = dev_dclose(dev, ap->a_fflag, S_IFCHR, ap->a_fp);
1198 /* node is now stale */
1199
1200 if (needrelock) {
1201 if (vn_lock(vp, LK_EXCLUSIVE |
1202 LK_RETRY |
1203 LK_FAILRECLAIM) != 0) {
1204 panic("devfs_spec_close: vnode %p "
1205 "unexpectedly could not be relocked",
1206 vp);
1207 }
1208 }
1209 } else {
1210 error = 0;
1211 }
1212 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() -2- \n");
1213
1214 /*
1215 * Track the actual opens and closes on the vnode. The last close
1216 * disassociates the rdev. If the rdev is already disassociated or
1217 * the opencount is already 0, the vnode might have been revoked
1218 * and no further opencount tracking occurs.
1219 */
1220 if (dev)
1221 release_dev(dev);
1222 skip:
1223 if (vp->v_opencount > 0)
1224 vop_stdclose(ap);
1225 return(error);
1226
1227 }
1228
1229
1230 static int
devfs_fo_close(struct file * fp)1231 devfs_fo_close(struct file *fp)
1232 {
1233 struct vnode *vp = (struct vnode *)fp->f_data;
1234 int error;
1235
1236 fp->f_ops = &badfileops;
1237 error = vn_close(vp, fp->f_flag, fp);
1238 devfs_clear_cdevpriv(fp);
1239
1240 return (error);
1241 }
1242
1243
1244 /*
1245 * Device-optimized file table vnode read routine.
1246 *
1247 * This bypasses the VOP table and talks directly to the device. Most
1248 * filesystems just route to specfs and can make this optimization.
1249 */
1250 static int
devfs_fo_read(struct file * fp,struct uio * uio,struct ucred * cred,int flags)1251 devfs_fo_read(struct file *fp, struct uio *uio,
1252 struct ucred *cred, int flags)
1253 {
1254 struct devfs_node *node;
1255 struct vnode *vp;
1256 int ioflag;
1257 int error;
1258 cdev_t dev;
1259
1260 KASSERT(uio->uio_td == curthread,
1261 ("uio_td %p is not td %p", uio->uio_td, curthread));
1262
1263 if (uio->uio_resid == 0)
1264 return 0;
1265
1266 vp = (struct vnode *)fp->f_data;
1267 if (vp == NULL || vp->v_type == VBAD)
1268 return EBADF;
1269
1270 node = DEVFS_NODE(vp);
1271
1272 if ((dev = vp->v_rdev) == NULL)
1273 return EBADF;
1274
1275 reference_dev(dev);
1276
1277 if ((flags & O_FOFFSET) == 0)
1278 uio->uio_offset = fp->f_offset;
1279
1280 ioflag = 0;
1281 if (flags & O_FBLOCKING) {
1282 /* ioflag &= ~IO_NDELAY; */
1283 } else if (flags & O_FNONBLOCKING) {
1284 ioflag |= IO_NDELAY;
1285 } else if (fp->f_flag & FNONBLOCK) {
1286 ioflag |= IO_NDELAY;
1287 }
1288 if (fp->f_flag & O_DIRECT) {
1289 ioflag |= IO_DIRECT;
1290 }
1291 ioflag |= sequential_heuristic(uio, fp);
1292
1293 error = dev_dread(dev, uio, ioflag, fp);
1294
1295 release_dev(dev);
1296 if (node)
1297 vfs_timestamp(&node->atime);
1298 if ((flags & O_FOFFSET) == 0)
1299 fp->f_offset = uio->uio_offset;
1300 fp->f_nextoff = uio->uio_offset;
1301
1302 return (error);
1303 }
1304
1305
1306 static int
devfs_fo_write(struct file * fp,struct uio * uio,struct ucred * cred,int flags)1307 devfs_fo_write(struct file *fp, struct uio *uio,
1308 struct ucred *cred, int flags)
1309 {
1310 struct devfs_node *node;
1311 struct vnode *vp;
1312 int ioflag;
1313 int error;
1314 cdev_t dev;
1315
1316 KASSERT(uio->uio_td == curthread,
1317 ("uio_td %p is not p %p", uio->uio_td, curthread));
1318
1319 vp = (struct vnode *)fp->f_data;
1320 if (vp == NULL || vp->v_type == VBAD)
1321 return EBADF;
1322
1323 node = DEVFS_NODE(vp);
1324
1325 if (vp->v_type == VREG)
1326 bwillwrite(uio->uio_resid);
1327
1328 vp = (struct vnode *)fp->f_data;
1329
1330 if ((dev = vp->v_rdev) == NULL)
1331 return EBADF;
1332
1333 reference_dev(dev);
1334
1335 if ((flags & O_FOFFSET) == 0)
1336 uio->uio_offset = fp->f_offset;
1337
1338 ioflag = IO_UNIT;
1339 if (vp->v_type == VREG &&
1340 ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) {
1341 ioflag |= IO_APPEND;
1342 }
1343
1344 if (flags & O_FBLOCKING) {
1345 /* ioflag &= ~IO_NDELAY; */
1346 } else if (flags & O_FNONBLOCKING) {
1347 ioflag |= IO_NDELAY;
1348 } else if (fp->f_flag & FNONBLOCK) {
1349 ioflag |= IO_NDELAY;
1350 }
1351 if (fp->f_flag & O_DIRECT) {
1352 ioflag |= IO_DIRECT;
1353 }
1354 if (flags & O_FASYNCWRITE) {
1355 /* ioflag &= ~IO_SYNC; */
1356 } else if (flags & O_FSYNCWRITE) {
1357 ioflag |= IO_SYNC;
1358 } else if (fp->f_flag & O_FSYNC) {
1359 ioflag |= IO_SYNC;
1360 }
1361
1362 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))
1363 ioflag |= IO_SYNC;
1364 ioflag |= sequential_heuristic(uio, fp);
1365
1366 error = dev_dwrite(dev, uio, ioflag, fp);
1367
1368 release_dev(dev);
1369 if (node) {
1370 vfs_timestamp(&node->atime);
1371 vfs_timestamp(&node->mtime);
1372 }
1373
1374 if ((flags & O_FOFFSET) == 0)
1375 fp->f_offset = uio->uio_offset;
1376 fp->f_nextoff = uio->uio_offset;
1377
1378 return (error);
1379 }
1380
1381
1382 static int
devfs_fo_stat(struct file * fp,struct stat * sb,struct ucred * cred)1383 devfs_fo_stat(struct file *fp, struct stat *sb, struct ucred *cred)
1384 {
1385 struct vnode *vp;
1386 struct vattr vattr;
1387 struct vattr *vap;
1388 u_short mode;
1389 cdev_t dev;
1390 int error;
1391
1392 vp = (struct vnode *)fp->f_data;
1393 if (vp == NULL || vp->v_type == VBAD)
1394 return EBADF;
1395
1396 error = vn_stat(vp, sb, cred);
1397 if (error)
1398 return (error);
1399
1400 vap = &vattr;
1401 error = VOP_GETATTR(vp, vap);
1402 if (error)
1403 return (error);
1404
1405 /*
1406 * Zero the spare stat fields
1407 */
1408 sb->st_lspare = 0;
1409 sb->st_qspare2 = 0;
1410
1411 /*
1412 * Copy from vattr table ... or not in case it's a cloned device
1413 */
1414 if (vap->va_fsid != VNOVAL)
1415 sb->st_dev = vap->va_fsid;
1416 else
1417 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
1418
1419 sb->st_ino = vap->va_fileid;
1420
1421 mode = vap->va_mode;
1422 mode |= S_IFCHR;
1423 sb->st_mode = mode;
1424
1425 if (vap->va_nlink > (nlink_t)-1)
1426 sb->st_nlink = (nlink_t)-1;
1427 else
1428 sb->st_nlink = vap->va_nlink;
1429
1430 sb->st_uid = vap->va_uid;
1431 sb->st_gid = vap->va_gid;
1432 sb->st_rdev = devid_from_dev(DEVFS_NODE(vp)->d_dev);
1433 sb->st_size = vap->va_bytes;
1434 sb->st_atimespec = vap->va_atime;
1435 sb->st_mtimespec = vap->va_mtime;
1436 sb->st_ctimespec = vap->va_ctime;
1437
1438 /*
1439 * A VCHR and VBLK device may track the last access and last modified
1440 * time independantly of the filesystem. This is particularly true
1441 * because device read and write calls may bypass the filesystem.
1442 */
1443 if (vp->v_type == VCHR || vp->v_type == VBLK) {
1444 dev = vp->v_rdev;
1445 if (dev != NULL) {
1446 if (dev->si_lastread) {
1447 sb->st_atimespec.tv_sec = time_second +
1448 (dev->si_lastread -
1449 time_uptime);
1450 sb->st_atimespec.tv_nsec = 0;
1451 }
1452 if (dev->si_lastwrite) {
1453 sb->st_mtimespec.tv_sec = time_second +
1454 (dev->si_lastwrite -
1455 time_uptime);
1456 sb->st_mtimespec.tv_nsec = 0;
1457 }
1458 }
1459 }
1460
1461 /*
1462 * According to www.opengroup.org, the meaning of st_blksize is
1463 * "a filesystem-specific preferred I/O block size for this
1464 * object. In some filesystem types, this may vary from file
1465 * to file"
1466 * Default to PAGE_SIZE after much discussion.
1467 */
1468
1469 sb->st_blksize = PAGE_SIZE;
1470
1471 sb->st_flags = vap->va_flags;
1472
1473 error = caps_priv_check(cred, SYSCAP_NOVFS_GENERATION);
1474 if (error)
1475 sb->st_gen = 0;
1476 else
1477 sb->st_gen = (u_int32_t)vap->va_gen;
1478
1479 sb->st_blocks = vap->va_bytes / S_BLKSIZE;
1480
1481 /*
1482 * This is for ABI compatibility <= 5.7 (for ABI change made in
1483 * 5.7 master).
1484 */
1485 sb->__old_st_blksize = sb->st_blksize;
1486
1487 return (0);
1488 }
1489
1490
1491 static int
devfs_fo_kqfilter(struct file * fp,struct knote * kn)1492 devfs_fo_kqfilter(struct file *fp, struct knote *kn)
1493 {
1494 struct vnode *vp;
1495 int error;
1496 cdev_t dev;
1497
1498 vp = (struct vnode *)fp->f_data;
1499 if (vp == NULL || vp->v_type == VBAD) {
1500 error = EBADF;
1501 goto done;
1502 }
1503 if ((dev = vp->v_rdev) == NULL) {
1504 error = EBADF;
1505 goto done;
1506 }
1507 reference_dev(dev);
1508
1509 error = dev_dkqfilter(dev, kn, fp);
1510
1511 release_dev(dev);
1512
1513 done:
1514 return (error);
1515 }
1516
1517 static int
devfs_fo_ioctl(struct file * fp,u_long com,caddr_t data,struct ucred * ucred,struct sysmsg * msg)1518 devfs_fo_ioctl(struct file *fp, u_long com, caddr_t data,
1519 struct ucred *ucred, struct sysmsg *msg)
1520 {
1521 #if 0
1522 struct devfs_node *node;
1523 #endif
1524 struct vnode *vp;
1525 struct vnode *ovp;
1526 cdev_t dev;
1527 int error;
1528 struct fiodname_args *name_args;
1529 size_t namlen;
1530 const char *name;
1531
1532 vp = ((struct vnode *)fp->f_data);
1533
1534 if ((dev = vp->v_rdev) == NULL)
1535 return EBADF; /* device was revoked */
1536
1537 reference_dev(dev);
1538
1539 #if 0
1540 node = DEVFS_NODE(vp);
1541 #endif
1542
1543 devfs_debug(DEVFS_DEBUG_DEBUG,
1544 "devfs_fo_ioctl() called! for dev %s\n",
1545 dev->si_name);
1546
1547 if (com == FIODTYPE) {
1548 *(int *)data = dev_dflags(dev) & D_TYPEMASK;
1549 error = 0;
1550 goto out;
1551 } else if (com == FIODNAME) {
1552 name_args = (struct fiodname_args *)data;
1553 name = dev->si_name;
1554 namlen = strlen(name) + 1;
1555
1556 devfs_debug(DEVFS_DEBUG_DEBUG,
1557 "ioctl, got: FIODNAME for %s\n", name);
1558
1559 if (namlen <= name_args->len)
1560 error = copyout(dev->si_name, name_args->name, namlen);
1561 else
1562 error = EINVAL;
1563
1564 devfs_debug(DEVFS_DEBUG_DEBUG,
1565 "ioctl stuff: error: %d\n", error);
1566 goto out;
1567 }
1568
1569 error = dev_dioctl(dev, com, data, fp->f_flag, ucred, msg, fp);
1570
1571 #if 0
1572 if (node) {
1573 vfs_timestamp(&node->atime);
1574 vfs_timestamp(&node->mtime);
1575 }
1576 #endif
1577 if (com == TIOCSCTTY) {
1578 devfs_debug(DEVFS_DEBUG_DEBUG,
1579 "devfs_fo_ioctl: got TIOCSCTTY on %s\n",
1580 dev->si_name);
1581 }
1582 if (error == 0 && com == TIOCSCTTY) {
1583 struct proc *p = curthread->td_proc;
1584 struct session *sess;
1585
1586 devfs_debug(DEVFS_DEBUG_DEBUG,
1587 "devfs_fo_ioctl: dealing with TIOCSCTTY on %s\n",
1588 dev->si_name);
1589 if (p == NULL) {
1590 error = ENOTTY;
1591 goto out;
1592 }
1593 sess = p->p_session;
1594
1595 /*
1596 * Do nothing if reassigning same control tty
1597 */
1598 if (sess->s_ttyvp == vp) {
1599 error = 0;
1600 goto out;
1601 }
1602
1603 /*
1604 * Get rid of reference to old control tty
1605 */
1606 ovp = sess->s_ttyvp;
1607 vref(vp);
1608 sess->s_ttyvp = vp;
1609 if (ovp)
1610 vrele(ovp);
1611 }
1612
1613 out:
1614 release_dev(dev);
1615 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_fo_ioctl() finished! \n");
1616 return (error);
1617 }
1618
1619 int
devfs_fo_seek(struct file * fp,off_t offset,int whence,off_t * res)1620 devfs_fo_seek(struct file *fp, off_t offset, int whence, off_t *res)
1621 {
1622 /*
1623 * NOTE: vnode_fileops uses exact same code
1624 */
1625 struct vnode *vp;
1626 struct vattr_lite lva;
1627 off_t new_offset;
1628 int error;
1629
1630 vp = (struct vnode *)fp->f_data;
1631
1632 switch (whence) {
1633 case L_INCR:
1634 spin_lock(&fp->f_spin);
1635 new_offset = fp->f_offset + offset;
1636 error = 0;
1637 break;
1638 case L_XTND:
1639 error = VOP_GETATTR_LITE(vp, &lva);
1640 spin_lock(&fp->f_spin);
1641 new_offset = offset + lva.va_size;
1642 break;
1643 case L_SET:
1644 new_offset = offset;
1645 error = 0;
1646 spin_lock(&fp->f_spin);
1647 break;
1648 default:
1649 new_offset = 0;
1650 error = EINVAL;
1651 spin_lock(&fp->f_spin);
1652 break;
1653 }
1654
1655 /*
1656 * Validate the seek position. Negative offsets are not allowed
1657 * for regular files or directories.
1658 *
1659 * Normally we would also not want to allow negative offsets for
1660 * character and block-special devices. However kvm addresses
1661 * on 64 bit architectures might appear to be negative and must
1662 * be allowed.
1663 */
1664 if (error == 0) {
1665 if (new_offset < 0 &&
1666 (vp->v_type == VREG || vp->v_type == VDIR)) {
1667 error = EINVAL;
1668 } else {
1669 fp->f_offset = new_offset;
1670 }
1671 }
1672 *res = fp->f_offset;
1673 spin_unlock(&fp->f_spin);
1674
1675 return (error);
1676 }
1677
1678 static int
devfs_spec_fsync(struct vop_fsync_args * ap)1679 devfs_spec_fsync(struct vop_fsync_args *ap)
1680 {
1681 struct vnode *vp = ap->a_vp;
1682 int error;
1683
1684 if (!vn_isdisk(vp, NULL))
1685 return (0);
1686
1687 /*
1688 * Flush all dirty buffers associated with a block device.
1689 */
1690 error = vfsync(vp, ap->a_waitfor, 10000, NULL, NULL);
1691 return (error);
1692 }
1693
1694 static int
devfs_spec_read(struct vop_read_args * ap)1695 devfs_spec_read(struct vop_read_args *ap)
1696 {
1697 struct devfs_node *node;
1698 struct vnode *vp;
1699 struct uio *uio;
1700 cdev_t dev;
1701 int error;
1702
1703 vp = ap->a_vp;
1704 dev = vp->v_rdev;
1705 uio = ap->a_uio;
1706 node = DEVFS_NODE(vp);
1707
1708 if (dev == NULL) /* device was revoked */
1709 return (EBADF);
1710 if (uio->uio_resid == 0)
1711 return (0);
1712
1713 vn_unlock(vp);
1714 error = dev_dread(dev, uio, ap->a_ioflag, NULL);
1715 vn_lock(vp, LK_SHARED | LK_RETRY);
1716
1717 if (node)
1718 vfs_timestamp(&node->atime);
1719
1720 return (error);
1721 }
1722
1723 /*
1724 * Vnode op for write
1725 *
1726 * spec_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag,
1727 * struct ucred *a_cred)
1728 */
1729 static int
devfs_spec_write(struct vop_write_args * ap)1730 devfs_spec_write(struct vop_write_args *ap)
1731 {
1732 struct devfs_node *node;
1733 struct vnode *vp;
1734 struct uio *uio;
1735 cdev_t dev;
1736 int error;
1737
1738 vp = ap->a_vp;
1739 dev = vp->v_rdev;
1740 uio = ap->a_uio;
1741 node = DEVFS_NODE(vp);
1742
1743 KKASSERT(uio->uio_segflg != UIO_NOCOPY);
1744
1745 if (dev == NULL) /* device was revoked */
1746 return (EBADF);
1747
1748 vn_unlock(vp);
1749 error = dev_dwrite(dev, uio, ap->a_ioflag, NULL);
1750 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1751
1752 if (node) {
1753 vfs_timestamp(&node->atime);
1754 vfs_timestamp(&node->mtime);
1755 }
1756
1757 return (error);
1758 }
1759
1760 /*
1761 * Device ioctl operation.
1762 *
1763 * spec_ioctl(struct vnode *a_vp, int a_command, caddr_t a_data,
1764 * int a_fflag, struct ucred *a_cred, struct sysmsg *msg)
1765 */
1766 static int
devfs_spec_ioctl(struct vop_ioctl_args * ap)1767 devfs_spec_ioctl(struct vop_ioctl_args *ap)
1768 {
1769 struct vnode *vp = ap->a_vp;
1770 #if 0
1771 struct devfs_node *node;
1772 #endif
1773 cdev_t dev;
1774
1775 if ((dev = vp->v_rdev) == NULL)
1776 return (EBADF); /* device was revoked */
1777 #if 0
1778 node = DEVFS_NODE(vp);
1779
1780 if (node) {
1781 vfs_timestamp(&node->atime);
1782 vfs_timestamp(&node->mtime);
1783 }
1784 #endif
1785
1786 return (dev_dioctl(dev, ap->a_command, ap->a_data, ap->a_fflag,
1787 ap->a_cred, ap->a_sysmsg, NULL));
1788 }
1789
1790 /*
1791 * spec_kqfilter(struct vnode *a_vp, struct knote *a_kn)
1792 */
1793 /* ARGSUSED */
1794 static int
devfs_spec_kqfilter(struct vop_kqfilter_args * ap)1795 devfs_spec_kqfilter(struct vop_kqfilter_args *ap)
1796 {
1797 struct vnode *vp = ap->a_vp;
1798 #if 0
1799 struct devfs_node *node;
1800 #endif
1801 cdev_t dev;
1802
1803 if ((dev = vp->v_rdev) == NULL)
1804 return (EBADF); /* device was revoked (EBADF) */
1805 #if 0
1806 node = DEVFS_NODE(vp);
1807
1808 if (node)
1809 vfs_timestamp(&node->atime);
1810 #endif
1811
1812 return (dev_dkqfilter(dev, ap->a_kn, NULL));
1813 }
1814
1815 /*
1816 * Convert a vnode strategy call into a device strategy call. Vnode strategy
1817 * calls are not limited to device DMA limits so we have to deal with the
1818 * case.
1819 *
1820 * spec_strategy(struct vnode *a_vp, struct bio *a_bio)
1821 */
1822 static int
devfs_spec_strategy(struct vop_strategy_args * ap)1823 devfs_spec_strategy(struct vop_strategy_args *ap)
1824 {
1825 struct bio *bio = ap->a_bio;
1826 struct buf *bp = bio->bio_buf;
1827 struct buf *nbp;
1828 struct vnode *vp;
1829 struct mount *mp;
1830 int chunksize;
1831 int maxiosize;
1832
1833 if (bp->b_cmd != BUF_CMD_READ && LIST_FIRST(&bp->b_dep) != NULL)
1834 buf_start(bp);
1835
1836 /*
1837 * Collect statistics on synchronous and asynchronous read
1838 * and write counts for disks that have associated filesystems.
1839 */
1840 vp = ap->a_vp;
1841 KKASSERT(vp->v_rdev != NULL); /* XXX */
1842 if (vn_isdisk(vp, NULL) && (mp = vp->v_rdev->si_mountpoint) != NULL) {
1843 if (bp->b_cmd == BUF_CMD_READ) {
1844 if (bp->b_flags & BIO_SYNC)
1845 mp->mnt_stat.f_syncreads++;
1846 else
1847 mp->mnt_stat.f_asyncreads++;
1848 } else {
1849 if (bp->b_flags & BIO_SYNC)
1850 mp->mnt_stat.f_syncwrites++;
1851 else
1852 mp->mnt_stat.f_asyncwrites++;
1853 }
1854 }
1855
1856 /*
1857 * Device iosize limitations only apply to read and write. Shortcut
1858 * the I/O if it fits.
1859 */
1860 if ((maxiosize = vp->v_rdev->si_iosize_max) == 0) {
1861 devfs_debug(DEVFS_DEBUG_DEBUG,
1862 "%s: si_iosize_max not set!\n",
1863 dev_dname(vp->v_rdev));
1864 maxiosize = MAXPHYS;
1865 }
1866 #if SPEC_CHAIN_DEBUG & 2
1867 maxiosize = 4096;
1868 #endif
1869 if (bp->b_bcount <= maxiosize ||
1870 (bp->b_cmd != BUF_CMD_READ && bp->b_cmd != BUF_CMD_WRITE)) {
1871 dev_dstrategy_chain(vp->v_rdev, bio);
1872 return (0);
1873 }
1874
1875 /*
1876 * Clone the buffer and set up an I/O chain to chunk up the I/O.
1877 */
1878 nbp = kmalloc(sizeof(*bp), M_DEVBUF, M_INTWAIT|M_ZERO);
1879 initbufbio(nbp);
1880 buf_dep_init(nbp);
1881 BUF_LOCK(nbp, LK_EXCLUSIVE);
1882 BUF_KERNPROC(nbp);
1883 nbp->b_vp = vp;
1884 nbp->b_flags = B_PAGING | B_KVABIO | (bp->b_flags & B_BNOCLIP);
1885 nbp->b_cpumask = bp->b_cpumask;
1886 nbp->b_data = bp->b_data;
1887 nbp->b_bio1.bio_done = devfs_spec_strategy_done;
1888 nbp->b_bio1.bio_offset = bio->bio_offset;
1889 nbp->b_bio1.bio_caller_info1.ptr = bio;
1890
1891 /*
1892 * Start the first transfer
1893 */
1894 if (vn_isdisk(vp, NULL))
1895 chunksize = vp->v_rdev->si_bsize_phys;
1896 else
1897 chunksize = DEV_BSIZE;
1898 chunksize = rounddown(maxiosize, chunksize);
1899 #if SPEC_CHAIN_DEBUG & 1
1900 devfs_debug(DEVFS_DEBUG_DEBUG,
1901 "spec_strategy chained I/O chunksize=%d\n",
1902 chunksize);
1903 #endif
1904 nbp->b_cmd = bp->b_cmd;
1905 nbp->b_bcount = chunksize;
1906 nbp->b_bufsize = chunksize; /* used to detect a short I/O */
1907 nbp->b_bio1.bio_caller_info2.index = chunksize;
1908
1909 #if SPEC_CHAIN_DEBUG & 1
1910 devfs_debug(DEVFS_DEBUG_DEBUG,
1911 "spec_strategy: chain %p offset %d/%d bcount %d\n",
1912 bp, 0, bp->b_bcount, nbp->b_bcount);
1913 #endif
1914
1915 dev_dstrategy(vp->v_rdev, &nbp->b_bio1);
1916
1917 if (DEVFS_NODE(vp)) {
1918 vfs_timestamp(&DEVFS_NODE(vp)->atime);
1919 vfs_timestamp(&DEVFS_NODE(vp)->mtime);
1920 }
1921
1922 return (0);
1923 }
1924
1925 /*
1926 * Chunked up transfer completion routine - chain transfers until done
1927 *
1928 * NOTE: MPSAFE callback.
1929 */
1930 static
1931 void
devfs_spec_strategy_done(struct bio * nbio)1932 devfs_spec_strategy_done(struct bio *nbio)
1933 {
1934 struct buf *nbp = nbio->bio_buf;
1935 struct bio *bio = nbio->bio_caller_info1.ptr; /* original bio */
1936 struct buf *bp = bio->bio_buf; /* original bp */
1937 int chunksize = nbio->bio_caller_info2.index; /* chunking */
1938 int boffset = nbp->b_data - bp->b_data;
1939
1940 if (nbp->b_flags & B_ERROR) {
1941 /*
1942 * An error terminates the chain, propogate the error back
1943 * to the original bp
1944 */
1945 bp->b_flags |= B_ERROR;
1946 bp->b_error = nbp->b_error;
1947 bp->b_resid = bp->b_bcount - boffset +
1948 (nbp->b_bcount - nbp->b_resid);
1949 #if SPEC_CHAIN_DEBUG & 1
1950 devfs_debug(DEVFS_DEBUG_DEBUG,
1951 "spec_strategy: chain %p error %d bcount %d/%d\n",
1952 bp, bp->b_error, bp->b_bcount,
1953 bp->b_bcount - bp->b_resid);
1954 #endif
1955 } else if (nbp->b_resid) {
1956 /*
1957 * A short read or write terminates the chain
1958 */
1959 bp->b_error = nbp->b_error;
1960 bp->b_resid = bp->b_bcount - boffset +
1961 (nbp->b_bcount - nbp->b_resid);
1962 #if SPEC_CHAIN_DEBUG & 1
1963 devfs_debug(DEVFS_DEBUG_DEBUG,
1964 "spec_strategy: chain %p short read(1) "
1965 "bcount %d/%d\n",
1966 bp, bp->b_bcount - bp->b_resid, bp->b_bcount);
1967 #endif
1968 } else if (nbp->b_bcount != nbp->b_bufsize) {
1969 /*
1970 * A short read or write can also occur by truncating b_bcount
1971 */
1972 #if SPEC_CHAIN_DEBUG & 1
1973 devfs_debug(DEVFS_DEBUG_DEBUG,
1974 "spec_strategy: chain %p short read(2) "
1975 "bcount %d/%d\n",
1976 bp, nbp->b_bcount + boffset, bp->b_bcount);
1977 #endif
1978 bp->b_error = 0;
1979 bp->b_bcount = nbp->b_bcount + boffset;
1980 bp->b_resid = nbp->b_resid;
1981 } else if (nbp->b_bcount + boffset == bp->b_bcount) {
1982 /*
1983 * No more data terminates the chain
1984 */
1985 #if SPEC_CHAIN_DEBUG & 1
1986 devfs_debug(DEVFS_DEBUG_DEBUG,
1987 "spec_strategy: chain %p finished bcount %d\n",
1988 bp, bp->b_bcount);
1989 #endif
1990 bp->b_error = 0;
1991 bp->b_resid = 0;
1992 } else {
1993 /*
1994 * Continue the chain
1995 */
1996 boffset += nbp->b_bcount;
1997 nbp->b_data = bp->b_data + boffset;
1998 nbp->b_bcount = bp->b_bcount - boffset;
1999 if (nbp->b_bcount > chunksize)
2000 nbp->b_bcount = chunksize;
2001 nbp->b_bio1.bio_done = devfs_spec_strategy_done;
2002 nbp->b_bio1.bio_offset = bio->bio_offset + boffset;
2003
2004 #if SPEC_CHAIN_DEBUG & 1
2005 devfs_debug(DEVFS_DEBUG_DEBUG,
2006 "spec_strategy: chain %p offset %d/%d bcount %d\n",
2007 bp, boffset, bp->b_bcount, nbp->b_bcount);
2008 #endif
2009
2010 dev_dstrategy(nbp->b_vp->v_rdev, &nbp->b_bio1);
2011 return;
2012 }
2013
2014 /*
2015 * Fall through to here on termination. biodone(bp) and
2016 * clean up and free nbp.
2017 */
2018 biodone(bio);
2019 BUF_UNLOCK(nbp);
2020 uninitbufbio(nbp);
2021 kfree(nbp, M_DEVBUF);
2022 }
2023
2024 /*
2025 * spec_freeblks(struct vnode *a_vp, daddr_t a_addr, daddr_t a_length)
2026 */
2027 static int
devfs_spec_freeblks(struct vop_freeblks_args * ap)2028 devfs_spec_freeblks(struct vop_freeblks_args *ap)
2029 {
2030 struct buf *bp;
2031
2032 /*
2033 * Must be a synchronous operation
2034 */
2035 KKASSERT(ap->a_vp->v_rdev != NULL);
2036 if ((ap->a_vp->v_rdev->si_flags & SI_CANFREE) == 0)
2037 return (0);
2038 bp = getpbuf(NULL);
2039 bp->b_cmd = BUF_CMD_FREEBLKS;
2040 bp->b_bio1.bio_flags |= BIO_SYNC;
2041 bp->b_bio1.bio_offset = ap->a_offset;
2042 bp->b_bio1.bio_done = biodone_sync;
2043 bp->b_bcount = ap->a_length;
2044 dev_dstrategy(ap->a_vp->v_rdev, &bp->b_bio1);
2045 biowait(&bp->b_bio1, "TRIM");
2046 relpbuf(bp, NULL);
2047
2048 return (0);
2049 }
2050
2051 /*
2052 * Implement degenerate case where the block requested is the block
2053 * returned, and assume that the entire device is contiguous in regards
2054 * to the contiguous block range (runp and runb).
2055 *
2056 * spec_bmap(struct vnode *a_vp, off_t a_loffset,
2057 * off_t *a_doffsetp, int *a_runp, int *a_runb)
2058 */
2059 static int
devfs_spec_bmap(struct vop_bmap_args * ap)2060 devfs_spec_bmap(struct vop_bmap_args *ap)
2061 {
2062 if (ap->a_doffsetp != NULL)
2063 *ap->a_doffsetp = ap->a_loffset;
2064 if (ap->a_runp != NULL)
2065 *ap->a_runp = MAXBSIZE;
2066 if (ap->a_runb != NULL) {
2067 if (ap->a_loffset < MAXBSIZE)
2068 *ap->a_runb = (int)ap->a_loffset;
2069 else
2070 *ap->a_runb = MAXBSIZE;
2071 }
2072 return (0);
2073 }
2074
2075
2076 /*
2077 * Special device advisory byte-level locks.
2078 *
2079 * spec_advlock(struct vnode *a_vp, caddr_t a_id, int a_op,
2080 * struct flock *a_fl, int a_flags)
2081 */
2082 /* ARGSUSED */
2083 static int
devfs_spec_advlock(struct vop_advlock_args * ap)2084 devfs_spec_advlock(struct vop_advlock_args *ap)
2085 {
2086 return ((ap->a_flags & F_POSIX) ? EINVAL : EOPNOTSUPP);
2087 }
2088
2089 /*
2090 * NOTE: MPSAFE callback.
2091 */
2092 static void
devfs_spec_getpages_iodone(struct bio * bio)2093 devfs_spec_getpages_iodone(struct bio *bio)
2094 {
2095 bio->bio_buf->b_cmd = BUF_CMD_DONE;
2096 wakeup(bio->bio_buf);
2097 }
2098
2099 /*
2100 * spec_getpages() - get pages associated with device vnode.
2101 *
2102 * Note that spec_read and spec_write do not use the buffer cache, so we
2103 * must fully implement getpages here.
2104 */
2105 static int
devfs_spec_getpages(struct vop_getpages_args * ap)2106 devfs_spec_getpages(struct vop_getpages_args *ap)
2107 {
2108 vm_offset_t kva;
2109 int error;
2110 int i, pcount, size;
2111 struct buf *bp;
2112 vm_page_t m;
2113 vm_ooffset_t offset;
2114 int toff, nextoff, nread;
2115 struct vnode *vp = ap->a_vp;
2116 int blksiz;
2117 int gotreqpage;
2118
2119 error = 0;
2120 pcount = round_page(ap->a_count) / PAGE_SIZE;
2121
2122 /*
2123 * Calculate the offset of the transfer and do sanity check.
2124 */
2125 offset = IDX_TO_OFF(ap->a_m[0]->pindex) + ap->a_offset;
2126
2127 /*
2128 * Round up physical size for real devices. We cannot round using
2129 * v_mount's block size data because v_mount has nothing to do with
2130 * the device. i.e. it's usually '/dev'. We need the physical block
2131 * size for the device itself.
2132 *
2133 * We can't use v_rdev->si_mountpoint because it only exists when the
2134 * block device is mounted. However, we can use v_rdev.
2135 */
2136 if (vn_isdisk(vp, NULL))
2137 blksiz = vp->v_rdev->si_bsize_phys;
2138 else
2139 blksiz = DEV_BSIZE;
2140
2141 size = roundup2(ap->a_count, blksiz);
2142
2143 bp = getpbuf_kva(NULL);
2144 kva = (vm_offset_t)bp->b_data;
2145
2146 /*
2147 * Map the pages to be read into the kva.
2148 */
2149 pmap_qenter_noinval(kva, ap->a_m, pcount);
2150
2151 /* Build a minimal buffer header. */
2152 bp->b_cmd = BUF_CMD_READ;
2153 bp->b_flags |= B_KVABIO;
2154 bp->b_bcount = size;
2155 bp->b_resid = 0;
2156 bsetrunningbufspace(bp, size);
2157
2158 bp->b_bio1.bio_offset = offset;
2159 bp->b_bio1.bio_done = devfs_spec_getpages_iodone;
2160
2161 mycpu->gd_cnt.v_vnodein++;
2162 mycpu->gd_cnt.v_vnodepgsin += pcount;
2163
2164 /* Do the input. */
2165 vn_strategy(ap->a_vp, &bp->b_bio1);
2166
2167 crit_enter();
2168
2169 /* We definitely need to be at splbio here. */
2170 while (bp->b_cmd != BUF_CMD_DONE)
2171 tsleep(bp, 0, "spread", 0);
2172
2173 crit_exit();
2174
2175 if (bp->b_flags & B_ERROR) {
2176 if (bp->b_error)
2177 error = bp->b_error;
2178 else
2179 error = EIO;
2180 }
2181
2182 /*
2183 * If EOF is encountered we must zero-extend the result in order
2184 * to ensure that the page does not contain garabge. When no
2185 * error occurs, an early EOF is indicated if b_bcount got truncated.
2186 * b_resid is relative to b_bcount and should be 0, but some devices
2187 * might indicate an EOF with b_resid instead of truncating b_bcount.
2188 */
2189 nread = bp->b_bcount - bp->b_resid;
2190 if (nread < ap->a_count) {
2191 bkvasync(bp);
2192 bzero((caddr_t)kva + nread, ap->a_count - nread);
2193 }
2194 pmap_qremove_noinval(kva, pcount);
2195
2196 gotreqpage = 0;
2197 for (i = 0, toff = 0; i < pcount; i++, toff = nextoff) {
2198 nextoff = toff + PAGE_SIZE;
2199 m = ap->a_m[i];
2200
2201 /*
2202 * NOTE: vm_page_undirty/clear_dirty etc do not clear the
2203 * pmap modified bit. pmap modified bit should have
2204 * already been cleared.
2205 */
2206 if (nextoff <= nread) {
2207 m->valid = VM_PAGE_BITS_ALL;
2208 vm_page_undirty(m);
2209 } else if (toff < nread) {
2210 /*
2211 * Since this is a VM request, we have to supply the
2212 * unaligned offset to allow vm_page_set_valid()
2213 * to zero sub-DEV_BSIZE'd portions of the page.
2214 */
2215 vm_page_set_valid(m, 0, nread - toff);
2216 vm_page_clear_dirty_end_nonincl(m, 0, nread - toff);
2217 } else {
2218 m->valid = 0;
2219 vm_page_undirty(m);
2220 }
2221
2222 if (i != ap->a_reqpage) {
2223 /*
2224 * Just in case someone was asking for this page we
2225 * now tell them that it is ok to use.
2226 */
2227 if (!error || (m->valid == VM_PAGE_BITS_ALL)) {
2228 if (m->valid) {
2229 if (m->flags & PG_REFERENCED) {
2230 vm_page_activate(m);
2231 } else {
2232 vm_page_deactivate(m);
2233 }
2234 vm_page_wakeup(m);
2235 } else {
2236 vm_page_free(m);
2237 }
2238 } else {
2239 vm_page_free(m);
2240 }
2241 } else if (m->valid) {
2242 gotreqpage = 1;
2243 /*
2244 * Since this is a VM request, we need to make the
2245 * entire page presentable by zeroing invalid sections.
2246 */
2247 if (m->valid != VM_PAGE_BITS_ALL)
2248 vm_page_zero_invalid(m, FALSE);
2249 }
2250 }
2251 if (!gotreqpage) {
2252 m = ap->a_m[ap->a_reqpage];
2253 devfs_debug(DEVFS_DEBUG_WARNING,
2254 "spec_getpages:(%s) I/O read failure: (error=%d) bp %p vp %p\n",
2255 devtoname(vp->v_rdev), error, bp, bp->b_vp);
2256 devfs_debug(DEVFS_DEBUG_WARNING,
2257 " size: %d, resid: %d, a_count: %d, valid: 0x%x\n",
2258 size, bp->b_resid, ap->a_count, m->valid);
2259 devfs_debug(DEVFS_DEBUG_WARNING,
2260 " nread: %d, reqpage: %d, pindex: %lu, pcount: %d\n",
2261 nread, ap->a_reqpage, (u_long)m->pindex, pcount);
2262 /*
2263 * Free the buffer header back to the swap buffer pool.
2264 */
2265 relpbuf(bp, NULL);
2266 return VM_PAGER_ERROR;
2267 }
2268 /*
2269 * Free the buffer header back to the swap buffer pool.
2270 */
2271 relpbuf(bp, NULL);
2272 if (DEVFS_NODE(ap->a_vp))
2273 vfs_timestamp(&DEVFS_NODE(ap->a_vp)->mtime);
2274 return VM_PAGER_OK;
2275 }
2276
2277 static __inline
2278 int
sequential_heuristic(struct uio * uio,struct file * fp)2279 sequential_heuristic(struct uio *uio, struct file *fp)
2280 {
2281 /*
2282 * Sequential heuristic - detect sequential operation
2283 */
2284 if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
2285 uio->uio_offset == fp->f_nextoff) {
2286 /*
2287 * XXX we assume that the filesystem block size is
2288 * the default. Not true, but still gives us a pretty
2289 * good indicator of how sequential the read operations
2290 * are.
2291 */
2292 int tmpseq = fp->f_seqcount;
2293
2294 tmpseq += howmany(uio->uio_resid, MAXBSIZE);
2295 if (tmpseq > IO_SEQMAX)
2296 tmpseq = IO_SEQMAX;
2297 fp->f_seqcount = tmpseq;
2298 return(fp->f_seqcount << IO_SEQSHIFT);
2299 }
2300
2301 /*
2302 * Not sequential, quick draw-down of seqcount
2303 */
2304 if (fp->f_seqcount > 1)
2305 fp->f_seqcount = 1;
2306 else
2307 fp->f_seqcount = 0;
2308 return(0);
2309 }
2310