xref: /netbsd-src/sys/fs/puffs/puffs_vfsops.c (revision 28e9fed55e050874f85dea9d258331d78863ce6b)
1 /*	$NetBSD: puffs_vfsops.c,v 1.126 2021/04/01 19:00:33 christos 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
20  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: puffs_vfsops.c,v 1.126 2021/04/01 19:00:33 christos Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37 #include <sys/mount.h>
38 #include <sys/extattr.h>
39 #include <sys/queue.h>
40 #include <sys/vnode.h>
41 #include <sys/dirent.h>
42 #include <sys/kauth.h>
43 #include <sys/proc.h>
44 #include <sys/module.h>
45 #include <sys/kthread.h>
46 
47 #include <uvm/uvm.h>
48 
49 #include <dev/putter/putter_sys.h>
50 
51 #include <miscfs/genfs/genfs.h>
52 
53 #include <fs/puffs/puffs_msgif.h>
54 #include <fs/puffs/puffs_sys.h>
55 
56 #include <lib/libkern/libkern.h>
57 
58 #include <nfs/nfsproto.h> /* for fh sizes */
59 
60 MODULE(MODULE_CLASS_VFS, puffs, "putter");
61 
62 VFS_PROTOS(puffs_vfsop);
63 
64 static struct putter_ops puffs_putter = {
65 	.pop_getout	= puffs_msgif_getout,
66 	.pop_releaseout	= puffs_msgif_releaseout,
67 	.pop_waitcount	= puffs_msgif_waitcount,
68 	.pop_dispatch	= puffs_msgif_dispatch,
69 	.pop_close	= puffs_msgif_close,
70 };
71 
72 static const struct genfs_ops puffs_genfsops = {
73         .gop_size = puffs_gop_size,
74 	.gop_write = genfs_gop_write,
75 	.gop_markupdate = puffs_gop_markupdate,
76 #if 0
77 	.gop_alloc, should ask userspace
78 #endif
79 	.gop_putrange = genfs_gop_putrange,
80 };
81 
82 /*
83  * Try to ensure data structures used by the puffs protocol
84  * do not unexpectedly change.
85  */
86 #if defined(__i386__) && defined(__ELF__)
87 CTASSERT(sizeof(struct puffs_kargs) == 3928);
88 CTASSERT(sizeof(struct vattr) == 136);
89 CTASSERT(sizeof(struct puffs_req) == 44);
90 #endif
91 
92 int
puffs_vfsop_mount(struct mount * mp,const char * path,void * data,size_t * data_len)93 puffs_vfsop_mount(struct mount *mp, const char *path, void *data,
94 	size_t *data_len)
95 {
96 	struct puffs_mount *pmp = NULL;
97 	struct puffs_kargs *args;
98 	char fstype[_VFS_NAMELEN];
99 	char *p;
100 	int error = 0, i;
101 	pid_t mntpid = curlwp->l_proc->p_pid;
102 
103 	if (data == NULL)
104 		return EINVAL;
105 	if (*data_len < sizeof *args)
106 		return EINVAL;
107 
108 	if (mp->mnt_flag & MNT_GETARGS) {
109 		pmp = MPTOPUFFSMP(mp);
110 		*(struct puffs_kargs *)data = pmp->pmp_args;
111 		*data_len = sizeof *args;
112 		return 0;
113 	}
114 
115 	/* update is not supported currently */
116 	if (mp->mnt_flag & MNT_UPDATE)
117 		return EOPNOTSUPP;
118 
119 	args = (struct puffs_kargs *)data;
120 
121 	if (args->pa_vers != PUFFSVERSION) {
122 		printf("puffs_mount: development version mismatch: "
123 		    "kernel %d, lib %d\n", PUFFSVERSION, args->pa_vers);
124 		error = EINVAL;
125 		goto out;
126 	}
127 
128 	if ((args->pa_flags & ~PUFFS_KFLAG_MASK) != 0) {
129 		printf("puffs_mount: invalid KFLAGs 0x%x\n", args->pa_flags);
130 		error = EINVAL;
131 		goto out;
132 	}
133 	if ((args->pa_fhflags & ~PUFFS_FHFLAG_MASK) != 0) {
134 		printf("puffs_mount: invalid FHFLAGs 0x%x\n", args->pa_fhflags);
135 		error = EINVAL;
136 		goto out;
137 	}
138 
139 	for (i = 0; i < __arraycount(args->pa_spare); i++) {
140 		if (args->pa_spare[i] != 0) {
141 			printf("puffs_mount: pa_spare[%d] = 0x%x\n",
142 			    i, args->pa_spare[i]);
143 			error = EINVAL;
144 			goto out;
145 		}
146 	}
147 
148 	/* use dummy value for passthrough */
149 	if (args->pa_fhflags & PUFFS_FHFLAG_PASSTHROUGH)
150 		args->pa_fhsize = sizeof(struct fid);
151 
152 	/* sanitize file handle length */
153 	if (PUFFS_TOFHSIZE(args->pa_fhsize) > FHANDLE_SIZE_MAX) {
154 		printf("puffs_mount: handle size %zu too large\n",
155 		    args->pa_fhsize);
156 		error = EINVAL;
157 		goto out;
158 	}
159 	/* sanity check file handle max sizes */
160 	if (args->pa_fhsize && args->pa_fhflags & PUFFS_FHFLAG_PROTOMASK) {
161 		size_t kfhsize = PUFFS_TOFHSIZE(args->pa_fhsize);
162 
163 		if (args->pa_fhflags & PUFFS_FHFLAG_NFSV2) {
164 			if (NFSX_FHTOOBIG_P(kfhsize, 0)) {
165 				printf("puffs_mount: fhsize larger than "
166 				    "NFSv2 max %d\n",
167 				    PUFFS_FROMFHSIZE(NFSX_V2FH));
168 				error = EINVAL;
169 				goto out;
170 			}
171 		}
172 
173 		if (args->pa_fhflags & PUFFS_FHFLAG_NFSV3) {
174 			if (NFSX_FHTOOBIG_P(kfhsize, 1)) {
175 				printf("puffs_mount: fhsize larger than "
176 				    "NFSv3 max %d\n",
177 				    PUFFS_FROMFHSIZE(NFSX_V3FHMAX));
178 				error = EINVAL;
179 				goto out;
180 			}
181 		}
182 	}
183 
184 	/* don't allow non-printing characters (like my sweet umlauts.. snif) */
185 	args->pa_typename[sizeof(args->pa_typename)-1] = '\0';
186 	for (p = args->pa_typename; *p; p++)
187 		if (*p < ' ' || *p > '~')
188 			*p = '.';
189 
190 	args->pa_mntfromname[sizeof(args->pa_mntfromname)-1] = '\0';
191 	for (p = args->pa_mntfromname; *p; p++)
192 		if (*p < ' ' || *p > '~')
193 			*p = '.';
194 
195 	/* build real name */
196 	(void)strlcpy(fstype, PUFFS_TYPEPREFIX, sizeof(fstype));
197 	(void)strlcat(fstype, args->pa_typename, sizeof(fstype));
198 
199 	/* inform user server if it got the max request size it wanted */
200 	if (args->pa_maxmsglen == 0 || args->pa_maxmsglen > PUFFS_MSG_MAXSIZE)
201 		args->pa_maxmsglen = PUFFS_MSG_MAXSIZE;
202 	else if (args->pa_maxmsglen < 2*PUFFS_MSGSTRUCT_MAX)
203 		args->pa_maxmsglen = 2*PUFFS_MSGSTRUCT_MAX;
204 
205 	(void)strlcpy(args->pa_typename, fstype, sizeof(args->pa_typename));
206 
207 	error = set_statvfs_info(path, UIO_USERSPACE, args->pa_mntfromname,
208 	    UIO_SYSSPACE, fstype, mp, curlwp);
209 	if (error)
210 		goto out;
211 	mp->mnt_stat.f_iosize = DEV_BSIZE;
212 	mp->mnt_stat.f_namemax = args->pa_svfsb.f_namemax;
213 
214 	/*
215 	 * We can't handle the VFS_STATVFS() mount_domount() does
216 	 * after VFS_MOUNT() because we'd deadlock, so handle it
217 	 * here already.
218 	 */
219 	struct statvfs *sb = STATVFSBUF_GET();
220 	puffs_statvfs_to_statvfs(&args->pa_svfsb, sb);
221 	copy_statvfs_info(sb, mp);
222 	STATVFSBUF_PUT(sb);
223 
224 	statvfs_to_puffs_statvfs(&mp->mnt_stat, &args->pa_svfsb);
225 
226 	KASSERT(curlwp != uvm.pagedaemon_lwp);
227 	pmp = kmem_zalloc(sizeof(struct puffs_mount), KM_SLEEP);
228 
229 	mp->mnt_fs_bshift = DEV_BSHIFT;
230 	mp->mnt_dev_bshift = DEV_BSHIFT;
231 	mp->mnt_flag &= ~MNT_LOCAL; /* we don't really know, so ... */
232 	mp->mnt_data = pmp;
233 
234 #if 0
235 	/*
236 	 * XXX: puffs code is MPSAFE.  However, VFS really isn't.
237 	 * Currently, there is nothing which protects an inode from
238 	 * reclaim while there are threads inside the file system.
239 	 * This means that in the event of a server crash, an MPSAFE
240 	 * mount is likely to end up accessing invalid memory.  For the
241 	 * non-mpsafe case, the kernel lock, general structure of
242 	 * puffs and pmp_refcount protect the threads during escape.
243 	 *
244 	 * Fixing this will require:
245 	 *  a) fixing vfs
246 	 * OR
247 	 *  b) adding a small sleep to puffs_msgif_close() between
248 	 *     userdead() and dounmount().
249 	 *     (well, this isn't really a fix, but would solve
250 	 *     99.999% of the race conditions).
251 	 *
252 	 * Also, in the event of "b", unmount -f should be used,
253 	 * like with any other file system, sparingly and only when
254 	 * it is "known" to be safe.
255 	 */
256 	mp->mnt_iflags |= IMNT_MPSAFE;
257 #endif
258 
259 	pmp->pmp_status = PUFFSTAT_MOUNTING;
260 	pmp->pmp_mp = mp;
261 	pmp->pmp_msg_maxsize = args->pa_maxmsglen;
262 	pmp->pmp_args = *args;
263 
264 	/*
265 	 * Inform the fileops processing code that we have a mountpoint.
266 	 * If it doesn't know about anyone with our pid/fd having the
267 	 * device open, punt
268 	 */
269 	if ((pmp->pmp_pi
270 	    = putter_attach(mntpid, args->pa_fd, pmp, &puffs_putter)) == NULL) {
271 		error = ENOENT;
272 		goto out;
273 	}
274 
275 	/* XXX: check parameters */
276 	pmp->pmp_root_cookie = args->pa_root_cookie;
277 	switch (args->pa_root_vtype) {
278 	case VNON: case VREG: case VDIR: case VBLK:
279 	case VCHR: case VLNK: case VSOCK: case VFIFO:
280 		break;
281 	default:
282 		error = EINVAL;
283 		goto out;
284 	}
285 	pmp->pmp_root_vtype = args->pa_root_vtype;
286 
287 	if (args->pa_root_vsize < 0) {
288 		error = EINVAL;
289 		goto out;
290 	}
291 	pmp->pmp_root_vsize = args->pa_root_vsize;
292 
293 	pmp->pmp_root_rdev = args->pa_root_rdev;
294 	pmp->pmp_docompat = args->pa_time32;
295 
296 	mutex_init(&pmp->pmp_lock, MUTEX_DEFAULT, IPL_NONE);
297 	mutex_init(&pmp->pmp_sopmtx, MUTEX_DEFAULT, IPL_NONE);
298 	cv_init(&pmp->pmp_msg_waiter_cv, "puffsget");
299 	cv_init(&pmp->pmp_refcount_cv, "puffsref");
300 	cv_init(&pmp->pmp_unmounting_cv, "puffsum");
301 	cv_init(&pmp->pmp_sopcv, "puffsop");
302 	TAILQ_INIT(&pmp->pmp_msg_touser);
303 	TAILQ_INIT(&pmp->pmp_msg_replywait);
304 	TAILQ_INIT(&pmp->pmp_sopfastreqs);
305 	TAILQ_INIT(&pmp->pmp_sopnodereqs);
306 
307 	if ((error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
308 	    puffs_sop_thread, pmp, NULL, "puffsop")) != 0)
309 		goto out;
310 	pmp->pmp_sopthrcount = 1;
311 
312 	DPRINTF(("puffs_mount: mount point at %p, puffs specific at %p\n",
313 	    mp, MPTOPUFFSMP(mp)));
314 
315 	vfs_getnewfsid(mp);
316 
317  out:
318 	if (error && pmp && pmp->pmp_pi)
319 		putter_detach(pmp->pmp_pi);
320 	if (error && pmp)
321 		kmem_free(pmp, sizeof(struct puffs_mount));
322 	return error;
323 }
324 
325 int
puffs_vfsop_start(struct mount * mp,int flags)326 puffs_vfsop_start(struct mount *mp, int flags)
327 {
328 	struct puffs_mount *pmp = MPTOPUFFSMP(mp);
329 
330 	KASSERT(pmp->pmp_status == PUFFSTAT_MOUNTING);
331 	pmp->pmp_status = PUFFSTAT_RUNNING;
332 
333 	return 0;
334 }
335 
336 int
puffs_vfsop_unmount(struct mount * mp,int mntflags)337 puffs_vfsop_unmount(struct mount *mp, int mntflags)
338 {
339 	PUFFS_MSG_VARS(vfs, unmount);
340 	struct puffs_mount *pmp;
341 	int error, force;
342 
343 	error = 0;
344 	force = mntflags & MNT_FORCE;
345 	pmp = MPTOPUFFSMP(mp);
346 
347 	DPRINTF(("puffs_unmount: detach filesystem from vfs, current "
348 	    "status 0x%x\n", pmp->pmp_status));
349 
350 	/*
351 	 * flush all the vnodes.  VOP_RECLAIM() takes care that the
352 	 * root vnode does not get flushed until unmount.  The
353 	 * userspace root node cookie is stored in the mount
354 	 * structure, so we can always re-instantiate a root vnode,
355 	 * should userspace unmount decide it doesn't want to
356 	 * cooperate.
357 	 */
358 	error = vflush(mp, NULLVP, force ? FORCECLOSE : 0);
359 	if (error)
360 		goto out;
361 
362 	/*
363 	 * If we are not DYING, we should ask userspace's opinion
364 	 * about the situation
365 	 */
366 	mutex_enter(&pmp->pmp_lock);
367 	if (pmp->pmp_status != PUFFSTAT_DYING) {
368 		pmp->pmp_unmounting = 1;
369 		mutex_exit(&pmp->pmp_lock);
370 
371 		PUFFS_MSG_ALLOC(vfs, unmount);
372 		puffs_msg_setinfo(park_unmount,
373 		    PUFFSOP_VFS, PUFFS_VFS_UNMOUNT, NULL);
374 		unmount_msg->pvfsr_flags = mntflags;
375 
376 		PUFFS_MSG_ENQUEUEWAIT(pmp, park_unmount, error);
377 		PUFFS_MSG_RELEASE(unmount);
378 
379 		error = checkerr(pmp, error, __func__);
380 		DPRINTF(("puffs_unmount: error %d force %d\n", error, force));
381 
382 		mutex_enter(&pmp->pmp_lock);
383 		pmp->pmp_unmounting = 0;
384 		cv_broadcast(&pmp->pmp_unmounting_cv);
385 	}
386 
387 	/*
388 	 * if userspace cooperated or we really need to die,
389 	 * screw what userland thinks and just die.
390 	 */
391 	if (error == 0 || force) {
392 		struct puffs_sopreq *psopr;
393 
394 		/* tell waiters & other resources to go unwait themselves */
395 		puffs_userdead(pmp);
396 		putter_detach(pmp->pmp_pi);
397 
398 		/*
399 		 * Wait until there are no more users for the mount resource.
400 		 * Notice that this is hooked against transport_close
401 		 * and return from touser.  In an ideal world, it would
402 		 * be hooked against final return from all operations.
403 		 * But currently it works well enough, since nobody
404 		 * does weird blocking voodoo after return from touser().
405 		 */
406 		while (pmp->pmp_refcount != 0)
407 			cv_wait(&pmp->pmp_refcount_cv, &pmp->pmp_lock);
408 		mutex_exit(&pmp->pmp_lock);
409 
410 		/*
411 		 * Release kernel thread now that there is nothing
412 		 * it would be wanting to lock.
413 		 */
414 		KASSERT(curlwp != uvm.pagedaemon_lwp);
415 		psopr = kmem_alloc(sizeof(*psopr), KM_SLEEP);
416 		psopr->psopr_sopreq = PUFFS_SOPREQSYS_EXIT;
417 		mutex_enter(&pmp->pmp_sopmtx);
418 		if (pmp->pmp_sopthrcount == 0) {
419 			mutex_exit(&pmp->pmp_sopmtx);
420 			kmem_free(psopr, sizeof(*psopr));
421 			mutex_enter(&pmp->pmp_sopmtx);
422 			KASSERT(pmp->pmp_sopthrcount == 0);
423 		} else {
424 			TAILQ_INSERT_TAIL(&pmp->pmp_sopfastreqs,
425 			    psopr, psopr_entries);
426 			cv_signal(&pmp->pmp_sopcv);
427 		}
428 		while (pmp->pmp_sopthrcount > 0)
429 			cv_wait(&pmp->pmp_sopcv, &pmp->pmp_sopmtx);
430 		mutex_exit(&pmp->pmp_sopmtx);
431 
432 		/* free resources now that we hopefully have no waiters left */
433 		cv_destroy(&pmp->pmp_unmounting_cv);
434 		cv_destroy(&pmp->pmp_refcount_cv);
435 		cv_destroy(&pmp->pmp_msg_waiter_cv);
436 		cv_destroy(&pmp->pmp_sopcv);
437 		mutex_destroy(&pmp->pmp_lock);
438 		mutex_destroy(&pmp->pmp_sopmtx);
439 
440 		kmem_free(pmp, sizeof(struct puffs_mount));
441 		error = 0;
442 	} else {
443 		mutex_exit(&pmp->pmp_lock);
444 	}
445 
446  out:
447 	DPRINTF(("puffs_unmount: return %d\n", error));
448 	return error;
449 }
450 
451 /*
452  * This doesn't need to travel to userspace
453  */
454 int
puffs_vfsop_root(struct mount * mp,int lktype,struct vnode ** vpp)455 puffs_vfsop_root(struct mount *mp, int lktype, struct vnode **vpp)
456 {
457 	struct puffs_mount *pmp = MPTOPUFFSMP(mp);
458 	int rv;
459 
460 	rv = puffs_cookie2vnode(pmp, pmp->pmp_root_cookie, vpp);
461 	KASSERT(rv != PUFFS_NOSUCHCOOKIE);
462 	if (rv != 0)
463 		return rv;
464 	rv = vn_lock(*vpp, lktype);
465 	if (rv != 0) {
466 		vrele(*vpp);
467 		*vpp = NULL;
468 		return rv;
469 	}
470 	return 0;
471 }
472 
473 int
puffs_vfsop_statvfs(struct mount * mp,struct statvfs * sbp)474 puffs_vfsop_statvfs(struct mount *mp, struct statvfs *sbp)
475 {
476 	PUFFS_MSG_VARS(vfs, statvfs);
477 	struct puffs_mount *pmp;
478 	int error = 0;
479 
480 	pmp = MPTOPUFFSMP(mp);
481 
482 	/*
483 	 * If we are mounting, it means that the userspace counterpart
484 	 * is calling mount(2), but mount(2) also calls statvfs.  So
485 	 * requesting statvfs from userspace would mean a deadlock.
486 	 * Compensate.
487 	 */
488 	if (__predict_false(pmp->pmp_status == PUFFSTAT_MOUNTING))
489 		return EINPROGRESS;
490 
491 	PUFFS_MSG_ALLOC(vfs, statvfs);
492 	puffs_msg_setinfo(park_statvfs, PUFFSOP_VFS, PUFFS_VFS_STATVFS, NULL);
493 
494 	PUFFS_MSG_ENQUEUEWAIT(pmp, park_statvfs, error);
495 	error = checkerr(pmp, error, __func__);
496 	statvfs_msg->pvfsr_sb.f_iosize = DEV_BSIZE;
497 
498 	/*
499 	 * Try to produce a sensible result even in the event
500 	 * of userspace error.
501 	 *
502 	 * XXX: cache the copy in non-error case
503 	 */
504 	if (!error) {
505 		puffs_statvfs_to_statvfs(&statvfs_msg->pvfsr_sb, sbp);
506 	}
507 	copy_statvfs_info(sbp, mp);
508 	if (!error) {
509 		statvfs_to_puffs_statvfs(sbp, &statvfs_msg->pvfsr_sb);
510 	}
511 
512 	PUFFS_MSG_RELEASE(statvfs);
513 	return error;
514 }
515 
516 static bool
pageflush_selector(void * cl,struct vnode * vp)517 pageflush_selector(void *cl, struct vnode *vp)
518 {
519 
520 	KASSERT(mutex_owned(vp->v_interlock));
521 
522 	return vp->v_type == VREG &&
523 	    !(LIST_EMPTY(&vp->v_dirtyblkhd) &&
524 	    (vp->v_iflag & VI_ONWORKLST) == 0);
525 
526 }
527 
528 static int
pageflush(struct mount * mp,kauth_cred_t cred,int waitfor)529 pageflush(struct mount *mp, kauth_cred_t cred, int waitfor)
530 {
531 	struct puffs_node *pn;
532 	struct vnode *vp;
533 	struct vnode_iterator *marker;
534 	int error, rv, fsyncwait;
535 
536 	error = 0;
537 	fsyncwait = (waitfor == MNT_WAIT) ? FSYNC_WAIT : 0;
538 
539 	/*
540 	 * Sync all cached data from regular vnodes (which are not
541 	 * currently locked, see below).  After this we call VFS_SYNC
542 	 * for the fs server, which should handle data and metadata for
543 	 * all the nodes it knows to exist.
544 	 */
545 	vfs_vnode_iterator_init(mp, &marker);
546 	while ((vp = vfs_vnode_iterator_next(marker, pageflush_selector,
547 	    NULL)))
548 	{
549 		/*
550 		 * Here we try to get a reference to the vnode and to
551 		 * lock it.  This is mostly cargo-culted, but I will
552 		 * offer an explanation to why I believe this might
553 		 * actually do the right thing.
554 		 *
555 		 * If the vnode is a goner, we quite obviously don't need
556 		 * to sync it.
557 		 *
558 		 * If the vnode was busy, we don't need to sync it because
559 		 * this is never called with MNT_WAIT except from
560 		 * dounmount(), when we are wait-flushing all the dirty
561 		 * vnodes through other routes in any case.  So there,
562 		 * sync() doesn't actually sync.  Happy now?
563 		 */
564 		error = vn_lock(vp, LK_EXCLUSIVE | LK_NOWAIT);
565 		if (error) {
566 			vrele(vp);
567 			continue;
568 		}
569 		pn = VPTOPP(vp);
570 		/* hmm.. is the FAF thing entirely sensible? */
571 		if (waitfor == MNT_LAZY) {
572 			mutex_enter(vp->v_interlock);
573 			pn->pn_stat |= PNODE_FAF;
574 			mutex_exit(vp->v_interlock);
575 		}
576 		rv = VOP_FSYNC(vp, cred, fsyncwait, 0, 0);
577 		if (waitfor == MNT_LAZY) {
578 			mutex_enter(vp->v_interlock);
579 			pn->pn_stat &= ~PNODE_FAF;
580 			mutex_exit(vp->v_interlock);
581 		}
582 		if (rv)
583 			error = rv;
584 		vput(vp);
585 	}
586 	vfs_vnode_iterator_destroy(marker);
587 
588 	return error;
589 }
590 
591 int
puffs_vfsop_sync(struct mount * mp,int waitfor,struct kauth_cred * cred)592 puffs_vfsop_sync(struct mount *mp, int waitfor, struct kauth_cred *cred)
593 {
594 	PUFFS_MSG_VARS(vfs, sync);
595 	struct puffs_mount *pmp = MPTOPUFFSMP(mp);
596 	int error, rv;
597 
598 	error = pageflush(mp, cred, waitfor);
599 
600 	/* sync fs */
601 	PUFFS_MSG_ALLOC(vfs, sync);
602 	sync_msg->pvfsr_waitfor = waitfor;
603 	puffs_credcvt(&sync_msg->pvfsr_cred, cred);
604 	puffs_msg_setinfo(park_sync, PUFFSOP_VFS, PUFFS_VFS_SYNC, NULL);
605 
606 	PUFFS_MSG_ENQUEUEWAIT(pmp, park_sync, rv);
607 	rv = checkerr(pmp, rv, __func__);
608 	if (rv)
609 		error = rv;
610 
611 	PUFFS_MSG_RELEASE(sync);
612 	return error;
613 }
614 
615 int
puffs_vfsop_fhtovp(struct mount * mp,struct fid * fhp,int lktype,struct vnode ** vpp)616 puffs_vfsop_fhtovp(struct mount *mp, struct fid *fhp, int lktype,
617     struct vnode **vpp)
618 {
619 	PUFFS_MSG_VARS(vfs, fhtonode);
620 	struct puffs_mount *pmp = MPTOPUFFSMP(mp);
621 	struct vnode *vp;
622 	void *fhdata;
623 	size_t argsize, fhlen;
624 	int error;
625 
626 	if (pmp->pmp_args.pa_fhsize == 0)
627 		return EOPNOTSUPP;
628 
629 	if (pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_PASSTHROUGH) {
630 		fhlen = fhp->fid_len;
631 		fhdata = fhp;
632 	} else {
633 		fhlen = PUFFS_FROMFHSIZE(fhp->fid_len);
634 		fhdata = fhp->fid_data;
635 
636 		if (pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_DYNAMIC) {
637 			if (pmp->pmp_args.pa_fhsize < fhlen)
638 				return EINVAL;
639 		} else {
640 			if (pmp->pmp_args.pa_fhsize != fhlen)
641 				return EINVAL;
642 		}
643 	}
644 
645 	argsize = sizeof(struct puffs_vfsmsg_fhtonode) + fhlen;
646 	puffs_msgmem_alloc(argsize, &park_fhtonode, (void *)&fhtonode_msg, 1);
647 	fhtonode_msg->pvfsr_dsize = fhlen;
648 	memcpy(fhtonode_msg->pvfsr_data, fhdata, fhlen);
649 	puffs_msg_setinfo(park_fhtonode, PUFFSOP_VFS, PUFFS_VFS_FHTOVP, NULL);
650 
651 	PUFFS_MSG_ENQUEUEWAIT(pmp, park_fhtonode, error);
652 	error = checkerr(pmp, error, __func__);
653 	if (error)
654 		goto out;
655 
656 	error = puffs_getvnode(mp, fhtonode_msg->pvfsr_fhcookie,
657 	    fhtonode_msg->pvfsr_vtype, fhtonode_msg->pvfsr_size,
658 	    fhtonode_msg->pvfsr_rdev, &vp);
659 	if (error)
660 		goto out;
661 	vn_lock(vp, lktype | LK_RETRY);
662 
663 	*vpp = vp;
664  out:
665 	puffs_msgmem_release(park_fhtonode);
666 	return error;
667 }
668 
669 int
puffs_vfsop_vptofh(struct vnode * vp,struct fid * fhp,size_t * fh_size)670 puffs_vfsop_vptofh(struct vnode *vp, struct fid *fhp, size_t *fh_size)
671 {
672 	PUFFS_MSG_VARS(vfs, nodetofh);
673 	struct puffs_mount *pmp = MPTOPUFFSMP(vp->v_mount);
674 	size_t argsize, fhlen;
675 	int error;
676 
677 	if (pmp->pmp_args.pa_fhsize == 0)
678 		return EOPNOTSUPP;
679 
680 	/* if file handles are static len, we can test len immediately */
681 	if (((pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_DYNAMIC) == 0)
682 	    && ((pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_PASSTHROUGH) == 0)
683 	    && (PUFFS_FROMFHSIZE(*fh_size) < pmp->pmp_args.pa_fhsize)) {
684 		*fh_size = PUFFS_TOFHSIZE(pmp->pmp_args.pa_fhsize);
685 		return E2BIG;
686 	}
687 
688 	if (pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_PASSTHROUGH)
689 		fhlen = *fh_size;
690 	else
691 		fhlen = PUFFS_FROMFHSIZE(*fh_size);
692 
693 	argsize = sizeof(struct puffs_vfsmsg_nodetofh) + fhlen;
694 	puffs_msgmem_alloc(argsize, &park_nodetofh, (void *)&nodetofh_msg, 1);
695 	nodetofh_msg->pvfsr_fhcookie = VPTOPNC(vp);
696 	nodetofh_msg->pvfsr_dsize = fhlen;
697 	puffs_msg_setinfo(park_nodetofh, PUFFSOP_VFS, PUFFS_VFS_VPTOFH, NULL);
698 
699 	PUFFS_MSG_ENQUEUEWAIT(pmp, park_nodetofh, error);
700 	error = checkerr(pmp, error, __func__);
701 
702 	if (pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_PASSTHROUGH)
703 		fhlen = nodetofh_msg->pvfsr_dsize;
704 	else if (pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_DYNAMIC)
705 		fhlen = PUFFS_TOFHSIZE(nodetofh_msg->pvfsr_dsize);
706 	else
707 		fhlen = PUFFS_TOFHSIZE(pmp->pmp_args.pa_fhsize);
708 
709 	if (error) {
710 		if (error == E2BIG)
711 			*fh_size = fhlen;
712 		goto out;
713 	}
714 
715 	if (fhlen > FHANDLE_SIZE_MAX) {
716 		puffs_senderr(pmp, PUFFS_ERR_VPTOFH, E2BIG,
717 		    "file handle too big", VPTOPNC(vp));
718 		error = EPROTO;
719 		goto out;
720 	}
721 
722 	if (*fh_size < fhlen) {
723 		*fh_size = fhlen;
724 		error = E2BIG;
725 		goto out;
726 	}
727 	*fh_size = fhlen;
728 
729 	if (fhp) {
730 		if (pmp->pmp_args.pa_fhflags & PUFFS_FHFLAG_PASSTHROUGH) {
731 			memcpy(fhp, nodetofh_msg->pvfsr_data, fhlen);
732 		} else {
733 			fhp->fid_len = *fh_size;
734 			memcpy(fhp->fid_data, nodetofh_msg->pvfsr_data,
735 			    nodetofh_msg->pvfsr_dsize);
736 		}
737 	}
738 
739  out:
740 	puffs_msgmem_release(park_nodetofh);
741 	return error;
742 }
743 
744 int
puffs_vfsop_loadvnode(struct mount * mp,struct vnode * vp,const void * key,size_t key_len,const void ** new_key)745 puffs_vfsop_loadvnode(struct mount *mp, struct vnode *vp,
746     const void *key, size_t key_len, const void **new_key)
747 {
748 	struct puffs_mount *pmp;
749 	struct puffs_node *pnode;
750 
751 	KASSERT(key_len == sizeof(puffs_cookie_t));
752 
753 	pmp = MPTOPUFFSMP(mp);
754 
755 	/* Allocate and initialize the pnode. */
756 	pnode = pool_get(&puffs_pnpool, PR_WAITOK);
757 	memset(pnode, 0, sizeof(struct puffs_node));
758 
759 	pnode->pn_vp = vp;
760 	memcpy(&pnode->pn_cookie, key, key_len);
761 	pnode->pn_refcount = 1;
762 	mutex_init(&pnode->pn_mtx, MUTEX_DEFAULT, IPL_NONE);
763 	mutex_init(&pnode->pn_sizemtx, MUTEX_DEFAULT, IPL_NONE);
764 	selinit(&pnode->pn_sel);
765 	vp->v_tag = VT_PUFFS;
766 	vp->v_type = VNON;
767 	vp->v_op = puffs_vnodeop_p;
768 	if (pnode->pn_cookie == pmp->pmp_root_cookie)
769 		vp->v_vflag |= VV_ROOT;
770 	vp->v_data = pnode;
771 
772 	genfs_node_init(vp, &puffs_genfsops);
773 	uvm_vnp_setsize(vp, 0);
774 
775 	*new_key = &pnode->pn_cookie;
776 	return 0;
777 }
778 
779 void
puffs_vfsop_init(void)780 puffs_vfsop_init(void)
781 {
782 
783 	/* some checks depend on this */
784 	KASSERT(VNOVAL == VSIZENOTSET);
785 
786 	pool_init(&puffs_pnpool, sizeof(struct puffs_node), 0, 0, 0,
787 	    "puffpnpl", &pool_allocator_nointr, IPL_NONE);
788 	pool_init(&puffs_vapool, sizeof(struct vattr), 0, 0, 0,
789 	    "puffvapl", &pool_allocator_nointr, IPL_NONE);
790 	puffs_msgif_init();
791 }
792 
793 void
puffs_vfsop_done(void)794 puffs_vfsop_done(void)
795 {
796 
797 	puffs_msgif_destroy();
798 	pool_destroy(&puffs_pnpool);
799 	pool_destroy(&puffs_vapool);
800 }
801 
802 int
puffs_vfsop_snapshot(struct mount * mp,struct vnode * vp,struct timespec * ts)803 puffs_vfsop_snapshot(struct mount *mp, struct vnode *vp, struct timespec *ts)
804 {
805 
806 	return EOPNOTSUPP;
807 }
808 
809 int
puffs_vfsop_extattrctl(struct mount * mp,int cmd,struct vnode * vp,int attrnamespace,const char * attrname)810 puffs_vfsop_extattrctl(struct mount *mp, int cmd, struct vnode *vp,
811 	int attrnamespace, const char *attrname)
812 {
813 	PUFFS_MSG_VARS(vfs, extattrctl);
814 	struct puffs_mount *pmp = MPTOPUFFSMP(mp);
815 	struct puffs_node *pnp;
816 	puffs_cookie_t pnc;
817 	int error, flags;
818 
819 	if (vp) {
820 		/* doesn't make sense for puffs servers */
821 		if (vp->v_mount != mp)
822 			return EXDEV;
823 		pnp = vp->v_data;
824 		pnc = pnp->pn_cookie;
825 		flags = PUFFS_EXTATTRCTL_HASNODE;
826 	} else {
827 		pnp = pnc = NULL;
828 		flags = 0;
829 	}
830 
831 	PUFFS_MSG_ALLOC(vfs, extattrctl);
832 	extattrctl_msg->pvfsr_cmd = cmd;
833 	extattrctl_msg->pvfsr_attrnamespace = attrnamespace;
834 	extattrctl_msg->pvfsr_flags = flags;
835 	if (attrname) {
836 		strlcpy(extattrctl_msg->pvfsr_attrname, attrname,
837 		    sizeof(extattrctl_msg->pvfsr_attrname));
838 		extattrctl_msg->pvfsr_flags |= PUFFS_EXTATTRCTL_HASATTRNAME;
839 	}
840 	puffs_msg_setinfo(park_extattrctl,
841 	    PUFFSOP_VFS, PUFFS_VFS_EXTATTRCTL, pnc);
842 
843 	puffs_msg_enqueue(pmp, park_extattrctl);
844 	if (vp) {
845 		mutex_enter(&pnp->pn_mtx);
846 		puffs_referencenode(pnp);
847 		mutex_exit(&pnp->pn_mtx);
848 		VOP_UNLOCK(vp);
849 	}
850 	error = puffs_msg_wait2(pmp, park_extattrctl, pnp, NULL);
851 	PUFFS_MSG_RELEASE(extattrctl);
852 	if (vp) {
853 		puffs_releasenode(pnp);
854 	}
855 
856 	return checkerr(pmp, error, __func__);
857 }
858 
859 const struct vnodeopv_desc * const puffs_vnodeopv_descs[] = {
860 	&puffs_vnodeop_opv_desc,
861 	&puffs_specop_opv_desc,
862 	&puffs_fifoop_opv_desc,
863 	&puffs_msgop_opv_desc,
864 	NULL,
865 };
866 
867 struct vfsops puffs_vfsops = {
868 	.vfs_name = MOUNT_PUFFS,
869 	.vfs_min_mount_data = sizeof (struct puffs_kargs),
870 	.vfs_mount = puffs_vfsop_mount,
871 	.vfs_start = puffs_vfsop_start,
872 	.vfs_unmount = puffs_vfsop_unmount,
873 	.vfs_root = puffs_vfsop_root,
874 	.vfs_quotactl = (void *)eopnotsupp,
875 	.vfs_statvfs = puffs_vfsop_statvfs,
876 	.vfs_sync = puffs_vfsop_sync,
877 	.vfs_vget = (void *)eopnotsupp,
878 	.vfs_loadvnode = puffs_vfsop_loadvnode,
879 	.vfs_fhtovp = puffs_vfsop_fhtovp,
880 	.vfs_vptofh = puffs_vfsop_vptofh,
881 	.vfs_init = puffs_vfsop_init,
882 	.vfs_done = puffs_vfsop_done,
883 	.vfs_snapshot = puffs_vfsop_snapshot,
884 	.vfs_extattrctl = puffs_vfsop_extattrctl,
885 	.vfs_suspendctl = genfs_suspendctl,
886 	.vfs_renamelock_enter = genfs_renamelock_enter,
887 	.vfs_renamelock_exit = genfs_renamelock_exit,
888 	.vfs_fsync = (void *)eopnotsupp,
889 	.vfs_opv_descs = puffs_vnodeopv_descs
890 };
891 
892 static int
puffs_modcmd(modcmd_t cmd,void * arg)893 puffs_modcmd(modcmd_t cmd, void *arg)
894 {
895 
896 	switch (cmd) {
897 	case MODULE_CMD_INIT:
898 		return vfs_attach(&puffs_vfsops);
899 	case MODULE_CMD_FINI:
900 		return vfs_detach(&puffs_vfsops);
901 	default:
902 		return ENOTTY;
903 	}
904 }
905