puffs_vfsops.c revision 1.20 1 /* $NetBSD: puffs_vfsops.c,v 1.20 2007/01/09 18:14:31 pooka Exp $ */
2
3 /*
4 * Copyright (c) 2005, 2006 Antti Kantee. All Rights Reserved.
5 *
6 * Development of this software was supported by the
7 * Google Summer of Code program and the Ulla Tuominen Foundation.
8 * The Google SoC project was mentored by Bill Studenmund.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The name of the company nor the name of the author may be used to
19 * endorse or promote products derived from this software without specific
20 * prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
23 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
28 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: puffs_vfsops.c,v 1.20 2007/01/09 18:14:31 pooka Exp $");
37
38 #include <sys/param.h>
39 #include <sys/mount.h>
40 #include <sys/malloc.h>
41 #include <sys/extattr.h>
42 #include <sys/queue.h>
43 #include <sys/vnode.h>
44 #include <sys/dirent.h>
45 #include <sys/kauth.h>
46
47 #include <lib/libkern/libkern.h>
48
49 #include <fs/puffs/puffs_msgif.h>
50 #include <fs/puffs/puffs_sys.h>
51
52 VFS_PROTOS(puffs);
53
54 MALLOC_DEFINE(M_PUFFS, "puffs", "pass-to-userspace file system structures");
55
56 int
57 puffs_mount(struct mount *mp, const char *path, void *data,
58 struct nameidata *ndp, struct lwp *l)
59 {
60 struct puffs_mount *pmp;
61 struct puffs_args *args;
62 char namebuf[PUFFSNAMESIZE+sizeof(PUFFS_NAMEPREFIX)+1]; /* spooky */
63 int error = 0;
64
65 if (mp->mnt_flag & MNT_GETARGS) {
66 pmp = MPTOPUFFSMP(mp);
67 return copyout(&pmp->pmp_args, data, sizeof(struct puffs_args));
68 }
69
70 /* update is not supported currently */
71 if (mp->mnt_flag & MNT_UPDATE)
72 return EOPNOTSUPP;
73
74 /*
75 * We need the file system name
76 */
77 if (!data)
78 return EINVAL;
79
80 MALLOC(args, struct puffs_args *, sizeof(struct puffs_args),
81 M_PUFFS, M_WAITOK);
82
83 error = copyin(data, args, sizeof(struct puffs_args));
84 if (error)
85 goto out;
86
87 /* devel phase */
88 if (args->pa_vers != (PUFFSVERSION | PUFFSDEVELVERS)) {
89 printf("puffs_mount: development version mismatch\n");
90 error = EINVAL;
91 goto out;
92 }
93
94 /* nuke spy bits */
95 args->pa_flags &= PUFFS_KFLAG_MASK;
96
97 /* build real name */
98 (void)strlcpy(namebuf, PUFFS_NAMEPREFIX, sizeof(namebuf));
99 (void)strlcat(namebuf, args->pa_name, sizeof(namebuf));
100
101 /* inform user server if it got the max request size it wanted */
102 if (args->pa_maxreqlen == 0 || args->pa_maxreqlen > PUFFS_REQ_MAXSIZE)
103 args->pa_maxreqlen = PUFFS_REQ_MAXSIZE;
104 else if (args->pa_maxreqlen < PUFFS_REQSTRUCT_MAX)
105 args->pa_maxreqlen = PUFFS_REQSTRUCT_MAX;
106 (void)strlcpy(args->pa_name, namebuf, sizeof(args->pa_name));
107
108 error = copyout(args, data, sizeof(struct puffs_args));
109 if (error)
110 goto out;
111
112 error = set_statvfs_info(path, UIO_USERSPACE, namebuf,
113 UIO_SYSSPACE, mp, l);
114 if (error)
115 goto out;
116 mp->mnt_stat.f_iosize = DEV_BSIZE;
117
118 MALLOC(pmp, struct puffs_mount *, sizeof(struct puffs_mount),
119 M_PUFFS, M_WAITOK | M_ZERO);
120
121 mp->mnt_fs_bshift = DEV_BSHIFT;
122 mp->mnt_dev_bshift = DEV_BSHIFT;
123 mp->mnt_flag &= ~MNT_LOCAL; /* we don't really know, so ... */
124 mp->mnt_data = pmp;
125
126 pmp->pmp_status = PUFFSTAT_MOUNTING;
127 pmp->pmp_nextreq = 0;
128 pmp->pmp_mp = mp;
129 pmp->pmp_req_maxsize = args->pa_maxreqlen;
130 pmp->pmp_args = *args;
131
132 /*
133 * Inform the fileops processing code that we have a mountpoint.
134 * If it doesn't know about anyone with our pid/fd having the
135 * device open, punt
136 */
137 if (puffs_setpmp(l->l_proc->p_pid, args->pa_fd, pmp)) {
138 FREE(pmp, M_PUFFS);
139 error = ENOENT;
140 goto out;
141 }
142
143 simple_lock_init(&pmp->pmp_lock);
144 TAILQ_INIT(&pmp->pmp_req_touser);
145 TAILQ_INIT(&pmp->pmp_req_replywait);
146 TAILQ_INIT(&pmp->pmp_req_sizepark);
147
148 DPRINTF(("puffs_mount: mount point at %p, puffs specific at %p\n",
149 mp, MPTOPUFFSMP(mp)));
150
151 vfs_getnewfsid(mp);
152
153 out:
154 FREE(args, M_PUFFS);
155 return error;
156 }
157
158 /*
159 * This is called from the first "Hello, I'm alive" ioctl
160 * from userspace.
161 */
162 int
163 puffs_start2(struct puffs_mount *pmp, struct puffs_startreq *sreq)
164 {
165 struct puffs_node *pn;
166 struct mount *mp;
167
168 mp = PMPTOMP(pmp);
169
170 simple_lock(&pmp->pmp_lock);
171
172 /*
173 * if someone has issued a VFS_ROOT() already, fill in the
174 * vnode cookie.
175 */
176 pn = NULL;
177 if (pmp->pmp_root) {
178 pn = VPTOPP(pmp->pmp_root);
179 pn->pn_cookie = sreq->psr_cookie;
180 }
181
182 /* We're good to fly */
183 pmp->pmp_rootcookie = sreq->psr_cookie;
184 pmp->pmp_status = PUFFSTAT_RUNNING;
185 simple_unlock(&pmp->pmp_lock);
186
187 /* do the VFS_STATVFS() we missed out on in sys_mount() */
188 copy_statvfs_info(&sreq->psr_sb, mp);
189 (void)memcpy(&mp->mnt_stat, &sreq->psr_sb, sizeof(mp->mnt_stat));
190 mp->mnt_stat.f_iosize = DEV_BSIZE;
191
192 DPRINTF(("puffs_start2: root vp %p, cur root pnode %p, cookie %p\n",
193 pmp->pmp_root, pn, sreq->psr_cookie));
194
195 return 0;
196 }
197
198 int
199 puffs_start(struct mount *mp, int flags, struct lwp *l)
200 {
201
202 /*
203 * This cannot travel to userspace, as this is called from
204 * the kernel context of the process doing mount(2). But
205 * it's probably a safe bet that the process doing mount(2)
206 * realizes it needs to start the filesystem also...
207 */
208 return 0;
209 }
210
211 int
212 puffs_unmount(struct mount *mp, int mntflags, struct lwp *l)
213 {
214 struct puffs_mount *pmp;
215 int error, force;
216
217 PUFFS_VFSREQ(unmount);
218
219 error = 0;
220 force = mntflags & MNT_FORCE;
221 pmp = MPTOPUFFSMP(mp);
222
223 DPRINTF(("puffs_unmount: detach filesystem from vfs, current "
224 "status 0x%x\n", pmp->pmp_status));
225
226 /*
227 * flush all the vnodes. VOP_RECLAIM() takes care that the
228 * root vnode does not get flushed until unmount. The
229 * userspace root node cookie is stored in the mount
230 * structure, so we can always re-instantiate a root vnode,
231 * should userspace unmount decide it doesn't want to
232 * cooperate.
233 */
234 error = vflush(mp, NULLVP, force ? FORCECLOSE : 0);
235 if (error)
236 goto out;
237
238 /*
239 * If we are not DYING, we should ask userspace's opinion
240 * about the situation
241 */
242 simple_lock(&pmp->pmp_lock);
243 if (pmp->pmp_status != PUFFSTAT_DYING) {
244 pmp->pmp_unmounting = 1;
245 simple_unlock(&pmp->pmp_lock);
246
247 unmount_arg.pvfsr_flags = mntflags;
248 unmount_arg.pvfsr_pid = puffs_lwp2pid(l);
249
250 error = puffs_vfstouser(pmp, PUFFS_VFS_UNMOUNT,
251 &unmount_arg, sizeof(unmount_arg));
252 DPRINTF(("puffs_unmount: error %d force %d\n", error, force));
253
254 simple_lock(&pmp->pmp_lock);
255 pmp->pmp_unmounting = 0;
256 wakeup(&pmp->pmp_unmounting);
257 }
258
259 /*
260 * if userspace cooperated or we really need to die,
261 * screw what userland thinks and just die.
262 */
263 if (error == 0 || force) {
264 pmp->pmp_status = PUFFSTAT_DYING;
265 puffs_nukebypmp(pmp);
266 simple_unlock(&pmp->pmp_lock);
267 FREE(pmp, M_PUFFS);
268 error = 0;
269 } else {
270 simple_unlock(&pmp->pmp_lock);
271 }
272
273 out:
274 DPRINTF(("puffs_unmount: return %d\n", error));
275 return error;
276 }
277
278 /*
279 * This doesn't need to travel to userspace
280 */
281 int
282 puffs_root(struct mount *mp, struct vnode **vpp)
283 {
284 struct puffs_mount *pmp;
285 struct puffs_node *pn;
286 struct vnode *vp;
287
288 pmp = MPTOPUFFSMP(mp);
289
290 /*
291 * pmp_lock must be held if vref()'ing or vrele()'ing the
292 * root vnode. the latter is controlled by puffs_inactive().
293 */
294 simple_lock(&pmp->pmp_lock);
295 vp = pmp->pmp_root;
296 if (vp) {
297 pn = VPTOPP(vp);
298 if (vget(vp, LK_EXCLUSIVE | LK_RETRY)) {
299 pmp->pmp_root = NULL;
300 goto grabnew;
301 }
302 simple_unlock(&pmp->pmp_lock);
303 *vpp = vp;
304 return 0;
305 }
306 grabnew:
307 simple_unlock(&pmp->pmp_lock);
308
309 /*
310 * So, didn't have the magic root vnode available.
311 * No matter, grab another an stuff it with the cookie.
312 */
313 if (puffs_getvnode(mp, pmp->pmp_rootcookie, VDIR, 0, 0, &vp))
314 panic("sloppy programming");
315
316 simple_lock(&pmp->pmp_lock);
317 /*
318 * check if by mysterious force someone else created a root
319 * vnode while we were executing.
320 */
321 if (pmp->pmp_root) {
322 vref(pmp->pmp_root);
323 simple_unlock(&pmp->pmp_lock);
324 puffs_putvnode(vp);
325 vn_lock(pmp->pmp_root, LK_EXCLUSIVE | LK_RETRY);
326 *vpp = pmp->pmp_root;
327 return 0;
328 }
329
330 /* store cache */
331 vp->v_flag = VROOT;
332 pmp->pmp_root = vp;
333 simple_unlock(&pmp->pmp_lock);
334
335 vn_lock(pmp->pmp_root, LK_EXCLUSIVE | LK_RETRY);
336
337 *vpp = vp;
338 return 0;
339 }
340
341 int
342 puffs_quotactl(struct mount *mp, int cmd, uid_t uid, void *arg, struct lwp *l)
343 {
344
345 return EOPNOTSUPP;
346 }
347
348 int
349 puffs_statvfs(struct mount *mp, struct statvfs *sbp, struct lwp *l)
350 {
351 struct puffs_vfsreq_statvfs *statvfs_arg; /* too big for stack */
352 struct puffs_mount *pmp;
353 int error = 0;
354
355 pmp = MPTOPUFFSMP(mp);
356
357 /*
358 * If we are mounting, it means that the userspace counterpart
359 * is calling mount(2), but mount(2) also calls statvfs. So
360 * requesting statvfs from userspace would mean a deadlock.
361 * Compensate.
362 */
363 if (pmp->pmp_status == PUFFSTAT_MOUNTING)
364 return EINPROGRESS;
365
366 /* too big for stack */
367 MALLOC(statvfs_arg, struct puffs_vfsreq_statvfs *,
368 sizeof(struct puffs_vfsreq_statvfs), M_PUFFS, M_WAITOK | M_ZERO);
369 statvfs_arg->pvfsr_pid = puffs_lwp2pid(l);
370
371 error = puffs_vfstouser(pmp, PUFFS_VFS_STATVFS,
372 statvfs_arg, sizeof(*statvfs_arg));
373 statvfs_arg->pvfsr_sb.f_iosize = DEV_BSIZE;
374
375 /*
376 * Try to produce a sensible result even in the event
377 * of userspace error.
378 *
379 * XXX: cache the copy in non-error case
380 */
381 if (!error) {
382 copy_statvfs_info(&statvfs_arg->pvfsr_sb, mp);
383 (void)memcpy(sbp, &statvfs_arg->pvfsr_sb,
384 sizeof(struct statvfs));
385 } else {
386 copy_statvfs_info(sbp, mp);
387 }
388
389 FREE(statvfs_arg, M_PUFFS);
390 return error;
391 }
392
393 int
394 puffs_sync(struct mount *mp, int waitfor, struct kauth_cred *cred,
395 struct lwp *l)
396 {
397 struct vnode *vp, *nvp;
398 int error, rv;
399
400 PUFFS_VFSREQ(sync);
401
402 error = 0;
403
404 /*
405 * Sync all data from nodes. The user server can still cache
406 * metadata and control its syncing with VFS_SYNC. However,
407 * we just push all data with VOP_FSYNC already here to avoid
408 * an extra pingpong query from userspace requesting that
409 * data (and besides, there's no framework yet to handle it).
410 */
411 simple_lock(&mntvnode_slock);
412 loop:
413 for (vp = TAILQ_FIRST(&mp->mnt_vnodelist); vp; vp = nvp) {
414 /* check if we're on the right list */
415 if (vp->v_mount != mp)
416 goto loop;
417
418 simple_lock(&vp->v_interlock);
419 nvp = TAILQ_NEXT(vp, v_mntvnodes);
420
421 if (vp->v_type != VREG || UVM_OBJ_IS_CLEAN(&vp->v_uobj)) {
422 simple_unlock(&vp->v_interlock);
423 continue;
424 }
425
426 simple_unlock(&mntvnode_slock);
427 /* XXX: PNODE_INACTIVE is b0rked */
428 rv = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK);
429 if (rv) {
430 simple_lock(&mntvnode_slock);
431 if (rv == ENOENT)
432 goto loop;
433 continue;
434 }
435
436 if ((rv = VOP_FSYNC(vp, cred,
437 waitfor == MNT_WAIT ? FSYNC_WAIT : 0,
438 0, 0, l)) != 0)
439 error = rv;
440 vput(vp);
441 simple_lock(&mntvnode_slock);
442 }
443 simple_unlock(&mntvnode_slock);
444
445 /* sync fs */
446 sync_arg.pvfsr_waitfor = waitfor;
447 puffs_credcvt(&sync_arg.pvfsr_cred, cred);
448 sync_arg.pvfsr_pid = puffs_lwp2pid(l);
449
450 rv = puffs_vfstouser(MPTOPUFFSMP(mp), PUFFS_VFS_SYNC,
451 &sync_arg, sizeof(sync_arg));
452 if (rv)
453 error = rv;
454
455 return error;
456 }
457
458 int
459 puffs_vget(struct mount *mp, ino_t ino, struct vnode **vpp)
460 {
461
462 return EOPNOTSUPP;
463 }
464
465 #if 0
466 /*ARGSUSED*/
467 int
468 puffs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp)
469 {
470
471 return EOPNOTSUPP;
472 }
473
474 /*ARGSUSED*/
475 int
476 puffs_vptofh(struct vnode *vp, struct fid *fhp)
477 {
478
479 return EOPNOTSUPP;
480 }
481 #endif
482
483 void
484 puffs_init()
485 {
486
487 #ifdef _LKM
488 malloc_type_attach(M_PUFFS);
489 pool_init(&puffs_pnpool, sizeof(struct puffs_node), 0, 0, 0,
490 "puffspnpl", &pool_allocator_nointr);
491 #endif
492
493 return;
494 }
495
496 void
497 puffs_done()
498 {
499
500 #ifdef _LKM
501 pool_destroy(&puffs_pnpool);
502 malloc_type_detach(M_PUFFS);
503 #endif
504
505 return;
506 }
507
508 int
509 puffs_snapshot(struct mount *mp, struct vnode *vp, struct timespec *ts)
510 {
511
512 return EOPNOTSUPP;
513 }
514
515 const struct vnodeopv_desc * const puffs_vnodeopv_descs[] = {
516 &puffs_vnodeop_opv_desc,
517 &puffs_specop_opv_desc,
518 &puffs_fifoop_opv_desc,
519 &puffs_msgop_opv_desc,
520 NULL,
521 };
522
523 struct vfsops puffs_vfsops = {
524 MOUNT_PUFFS,
525 puffs_mount, /* mount */
526 puffs_start, /* start */
527 puffs_unmount, /* unmount */
528 puffs_root, /* root */
529 puffs_quotactl, /* quotactl */
530 puffs_statvfs, /* statvfs */
531 puffs_sync, /* sync */
532 puffs_vget, /* vget */
533 (void *)eopnotsupp, /* fhtovp */
534 (void *)eopnotsupp, /* vptofh */
535 puffs_init, /* init */
536 NULL, /* reinit */
537 puffs_done, /* done */
538 NULL, /* mountroot */
539 puffs_snapshot, /* snapshot */
540 vfs_stdextattrctl, /* extattrctl */
541 puffs_vnodeopv_descs, /* vnodeops */
542 0, /* refcount */
543 { NULL, NULL }
544 };
545 VFS_ATTACH(puffs_vfsops);
546