1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24  *
25  *  	Copyright (c) 1983,1984,1985,1986,1987,1988,1989  AT&T.
26  *	All rights reserved.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/thread.h>
32 #include <sys/t_lock.h>
33 #include <sys/time.h>
34 #include <sys/vnode.h>
35 #include <sys/vfs.h>
36 #include <sys/errno.h>
37 #include <sys/buf.h>
38 #include <sys/stat.h>
39 #include <sys/cred.h>
40 #include <sys/kmem.h>
41 #include <sys/debug.h>
42 #include <sys/vmsystm.h>
43 #include <sys/flock.h>
44 #include <sys/share.h>
45 #include <sys/cmn_err.h>
46 #include <sys/tiuser.h>
47 #include <sys/sysmacros.h>
48 #include <sys/callb.h>
49 #include <sys/acl.h>
50 #include <sys/kstat.h>
51 #include <sys/signal.h>
52 #include <sys/list.h>
53 #include <sys/zone.h>
54 
55 #include <netsmb/smb.h>
56 #include <netsmb/smb_conn.h>
57 #include <netsmb/smb_subr.h>
58 
59 #include <smbfs/smbfs.h>
60 #include <smbfs/smbfs_node.h>
61 #include <smbfs/smbfs_subr.h>
62 
63 #include <vm/hat.h>
64 #include <vm/as.h>
65 #include <vm/page.h>
66 #include <vm/pvn.h>
67 #include <vm/seg.h>
68 #include <vm/seg_map.h>
69 #include <vm/seg_vn.h>
70 
71 static int smbfs_getattr_cache(vnode_t *, struct smbfattr *);
72 static int smbfattr_to_vattr(vnode_t *, struct smbfattr *,
73 	struct vattr *);
74 
75 /*
76  * The following code provide zone support in order to perform an action
77  * for each smbfs mount in a zone.  This is also where we would add
78  * per-zone globals and kernel threads for the smbfs module (since
79  * they must be terminated by the shutdown callback).
80  */
81 
82 struct smi_globals {
83 	kmutex_t	smg_lock;  /* lock protecting smg_list */
84 	list_t		smg_list;  /* list of SMBFS mounts in zone */
85 	boolean_t	smg_destructor_called;
86 };
87 typedef struct smi_globals smi_globals_t;
88 
89 static zone_key_t smi_list_key;
90 
91 /*
92  * Attributes caching:
93  *
94  * Attributes are cached in the smbnode in struct vattr form.
95  * There is a time associated with the cached attributes (r_attrtime)
96  * which tells whether the attributes are valid. The time is initialized
97  * to the difference between current time and the modify time of the vnode
98  * when new attributes are cached. This allows the attributes for
99  * files that have changed recently to be timed out sooner than for files
100  * that have not changed for a long time. There are minimum and maximum
101  * timeout values that can be set per mount point.
102  */
103 
104 /*
105  * Validate caches by checking cached attributes. If they have timed out
106  * get the attributes from the server and compare mtimes. If mtimes are
107  * different purge all caches for this vnode.
108  */
109 int
110 smbfs_validate_caches(
111 	struct vnode *vp,
112 	cred_t *cr)
113 {
114 	struct vattr va;
115 
116 	va.va_mask = AT_SIZE;
117 	return (smbfsgetattr(vp, &va, cr));
118 }
119 
120 /*
121  * Purge all of the various data caches.
122  */
123 /*ARGSUSED*/
124 void
125 smbfs_purge_caches(struct vnode *vp)
126 {
127 #if 0	/* not yet: mmap support */
128 	/*
129 	 * NFS: Purge the DNLC for this vp,
130 	 * Clear any readdir state bits,
131 	 * the readlink response cache, ...
132 	 */
133 	smbnode_t *np = VTOSMB(vp);
134 
135 	/*
136 	 * Flush the page cache.
137 	 */
138 	if (vn_has_cached_data(vp)) {
139 		(void) VOP_PUTPAGE(vp, (u_offset_t)0, 0, B_INVAL, cr, NULL);
140 	}
141 #endif	/* not yet */
142 }
143 
144 /*
145  * Check the attribute cache to see if the new attributes match
146  * those cached.  If they do, the various `data' caches are
147  * considered to be good.  Otherwise, purge the cached data.
148  */
149 void
150 smbfs_cache_check(
151 	struct vnode *vp,
152 	struct smbfattr *fap)
153 {
154 	smbnode_t *np;
155 	int purge_data = 0;
156 	int purge_acl = 0;
157 
158 	np = VTOSMB(vp);
159 	mutex_enter(&np->r_statelock);
160 
161 	/*
162 	 * Compare with NFS macro: CACHE_VALID
163 	 * If the mtime or size has changed,
164 	 * purge cached data.
165 	 */
166 	if (np->r_attr.fa_mtime.tv_sec != fap->fa_mtime.tv_sec ||
167 	    np->r_attr.fa_mtime.tv_nsec != fap->fa_mtime.tv_nsec)
168 		purge_data = 1;
169 	if (np->r_attr.fa_size != fap->fa_size)
170 		purge_data = 1;
171 
172 	if (np->r_attr.fa_ctime.tv_sec != fap->fa_ctime.tv_sec ||
173 	    np->r_attr.fa_ctime.tv_nsec != fap->fa_ctime.tv_nsec)
174 		purge_acl = 1;
175 
176 	if (purge_acl) {
177 		/* just invalidate r_secattr (XXX: OK?) */
178 		np->r_sectime = gethrtime();
179 	}
180 
181 	mutex_exit(&np->r_statelock);
182 
183 	if (purge_data)
184 		smbfs_purge_caches(vp);
185 }
186 
187 /*
188  * Set attributes cache for given vnode using vnode attributes.
189  * From NFS: nfs_attrcache_va
190  */
191 #if 0 	/* not yet (not sure if we need this) */
192 void
193 smbfs_attrcache_va(vnode_t *vp, struct vattr *vap)
194 {
195 	smbfattr_t fa;
196 	smbnode_t *np;
197 
198 	vattr_to_fattr(vp, vap, &fa);
199 	smbfs_attrcache_fa(vp, &fa);
200 }
201 #endif	/* not yet */
202 
203 /*
204  * Set attributes cache for given vnode using SMB fattr
205  * and update the attribute cache timeout.
206  *
207  * From NFS: nfs_attrcache, nfs_attrcache_va
208  */
209 void
210 smbfs_attrcache_fa(vnode_t *vp, struct smbfattr *fap)
211 {
212 	smbnode_t *np;
213 	smbmntinfo_t *smi;
214 	hrtime_t delta, now;
215 	u_offset_t newsize;
216 	vtype_t	 vtype, oldvt;
217 	mode_t mode;
218 
219 	np = VTOSMB(vp);
220 	smi = VTOSMI(vp);
221 
222 	/*
223 	 * We allow v_type to change, so set that here
224 	 * (and the mode, which depends on the type).
225 	 */
226 	if (fap->fa_attr & SMB_FA_DIR) {
227 		vtype = VDIR;
228 		mode = smi->smi_dmode;
229 	} else {
230 		vtype = VREG;
231 		mode = smi->smi_fmode;
232 	}
233 
234 	mutex_enter(&np->r_statelock);
235 	now = gethrtime();
236 
237 	/*
238 	 * Delta is the number of nanoseconds that we will
239 	 * cache the attributes of the file.  It is based on
240 	 * the number of nanoseconds since the last time that
241 	 * we detected a change.  The assumption is that files
242 	 * that changed recently are likely to change again.
243 	 * There is a minimum and a maximum for regular files
244 	 * and for directories which is enforced though.
245 	 *
246 	 * Using the time since last change was detected
247 	 * eliminates direct comparison or calculation
248 	 * using mixed client and server times.  SMBFS
249 	 * does not make any assumptions regarding the
250 	 * client and server clocks being synchronized.
251 	 */
252 	if (fap->fa_mtime.tv_sec  != np->r_attr.fa_mtime.tv_sec ||
253 	    fap->fa_mtime.tv_nsec != np->r_attr.fa_mtime.tv_nsec ||
254 	    fap->fa_size	  != np->r_attr.fa_size)
255 		np->r_mtime = now;
256 
257 	if ((smi->smi_flags & SMI_NOAC) || (vp->v_flag & VNOCACHE))
258 		delta = 0;
259 	else {
260 		delta = now - np->r_mtime;
261 		if (vtype == VDIR) {
262 			if (delta < smi->smi_acdirmin)
263 				delta = smi->smi_acdirmin;
264 			else if (delta > smi->smi_acdirmax)
265 				delta = smi->smi_acdirmax;
266 		} else {
267 			if (delta < smi->smi_acregmin)
268 				delta = smi->smi_acregmin;
269 			else if (delta > smi->smi_acregmax)
270 				delta = smi->smi_acregmax;
271 		}
272 	}
273 
274 	np->r_attrtime = now + delta;
275 	np->r_attr = *fap;
276 	np->n_mode = mode;
277 	oldvt = vp->v_type;
278 	vp->v_type = vtype;
279 
280 	/*
281 	 * Shall we update r_size? (local notion of size)
282 	 *
283 	 * The real criteria for updating r_size should be:
284 	 * if the file has grown on the server, or if
285 	 * the client has not modified the file.
286 	 *
287 	 * Also deal with the fact that SMB presents
288 	 * directories as having size=0.  Doing that
289 	 * here and leaving fa_size as returned OtW
290 	 * avoids fixing the size lots of places.
291 	 */
292 	newsize = fap->fa_size;
293 	if (vtype == VDIR && newsize < DEV_BSIZE)
294 		newsize = DEV_BSIZE;
295 
296 	if (np->r_size != newsize) {
297 #if 0	/* not yet: mmap support */
298 		if (!vn_has_cached_data(vp) || ...)
299 			/* XXX: See NFS page cache code. */
300 #endif	/* not yet */
301 		/* OK to set the size. */
302 		np->r_size = newsize;
303 	}
304 
305 	/* NFS: np->r_flags &= ~RWRITEATTR; */
306 	np->n_flag &= ~NATTRCHANGED;
307 
308 	mutex_exit(&np->r_statelock);
309 
310 	if (oldvt != vtype) {
311 		SMBVDEBUG("vtype change %d to %d\n", oldvt, vtype);
312 	}
313 }
314 
315 /*
316  * Fill in attribute from the cache.
317  *
318  * If valid, copy to *fap and return zero,
319  * otherwise return an error.
320  *
321  * From NFS: nfs_getattr_cache()
322  */
323 int
324 smbfs_getattr_cache(vnode_t *vp, struct smbfattr *fap)
325 {
326 	smbnode_t *np;
327 	int error;
328 
329 	np = VTOSMB(vp);
330 
331 	mutex_enter(&np->r_statelock);
332 	if (gethrtime() >= np->r_attrtime) {
333 		/* cache expired */
334 		error = ENOENT;
335 	} else {
336 		/* cache is valid */
337 		*fap = np->r_attr;
338 		error = 0;
339 	}
340 	mutex_exit(&np->r_statelock);
341 
342 	return (error);
343 }
344 
345 /*
346  * Get attributes over-the-wire and update attributes cache
347  * if no error occurred in the over-the-wire operation.
348  * Return 0 if successful, otherwise error.
349  * From NFS: nfs_getattr_otw
350  */
351 int
352 smbfs_getattr_otw(vnode_t *vp, struct smbfattr *fap, cred_t *cr)
353 {
354 	struct smbnode *np;
355 	struct smb_cred scred;
356 	int error;
357 
358 	np = VTOSMB(vp);
359 
360 	/*
361 	 * NFS uses the ACL rpc here (if smi_flags & SMI_ACL)
362 	 * With SMB, getting the ACL is a significantly more
363 	 * expensive operation, so we do that only when asked
364 	 * for the uid/gid.  See smbfsgetattr().
365 	 */
366 
367 	/* Shared lock for (possible) n_fid use. */
368 	if (smbfs_rw_enter_sig(&np->r_lkserlock, RW_READER, SMBINTR(vp)))
369 		return (EINTR);
370 	smb_credinit(&scred, cr);
371 
372 	bzero(fap, sizeof (*fap));
373 	error = smbfs_smb_getfattr(np, fap, &scred);
374 
375 	smb_credrele(&scred);
376 	smbfs_rw_exit(&np->r_lkserlock);
377 
378 	if (error) {
379 		/* NFS had: PURGE_STALE_FH(error, vp, cr) */
380 		smbfs_attrcache_remove(np);
381 		if (error == ENOENT || error == ENOTDIR) {
382 			/*
383 			 * Getattr failed because the object was
384 			 * removed or renamed by another client.
385 			 * Remove any cached attributes under it.
386 			 */
387 			smbfs_attrcache_prune(np);
388 		}
389 		return (error);
390 	}
391 
392 	/*
393 	 * NFS: smbfs_cache_fattr(vap, fa, vap, t, cr);
394 	 * which did: fattr_to_vattr, nfs_attr_cache.
395 	 * We cache the fattr form, so just do the
396 	 * cache check and store the attributes.
397 	 */
398 	smbfs_cache_check(vp, fap);
399 	smbfs_attrcache_fa(vp, fap);
400 
401 	return (0);
402 }
403 
404 /*
405  * Return either cached or remote attributes. If get remote attr
406  * use them to check and invalidate caches, then cache the new attributes.
407  *
408  * From NFS: nfsgetattr()
409  */
410 int
411 smbfsgetattr(vnode_t *vp, struct vattr *vap, cred_t *cr)
412 {
413 	struct smbfattr fa;
414 	smbmntinfo_t *smi;
415 	uint_t mask;
416 	int error;
417 
418 	smi = VTOSMI(vp);
419 
420 	ASSERT(curproc->p_zone == smi->smi_zone_ref.zref_zone);
421 
422 	/*
423 	 * If asked for UID or GID, update n_uid, n_gid.
424 	 */
425 	mask = AT_ALL;
426 	if (vap->va_mask & (AT_UID | AT_GID)) {
427 		if (smi->smi_flags & SMI_ACL)
428 			(void) smbfs_acl_getids(vp, cr);
429 		/* else leave as set in make_smbnode */
430 	} else {
431 		mask &= ~(AT_UID | AT_GID);
432 	}
433 
434 	/*
435 	 * If we've got cached attributes, just use them;
436 	 * otherwise go to the server to get attributes,
437 	 * which will update the cache in the process.
438 	 */
439 	error = smbfs_getattr_cache(vp, &fa);
440 	if (error)
441 		error = smbfs_getattr_otw(vp, &fa, cr);
442 	if (error)
443 		return (error);
444 
445 	/*
446 	 * Re. client's view of the file size, see:
447 	 * smbfs_attrcache_fa, smbfs_getattr_otw
448 	 */
449 
450 	error = smbfattr_to_vattr(vp, &fa, vap);
451 	vap->va_mask = mask;
452 
453 	return (error);
454 }
455 
456 
457 /*
458  * Convert SMB over the wire attributes to vnode form.
459  * Returns 0 for success, error if failed (overflow, etc).
460  * From NFS: nattr_to_vattr()
461  */
462 int
463 smbfattr_to_vattr(vnode_t *vp, struct smbfattr *fa, struct vattr *vap)
464 {
465 	struct smbnode *np = VTOSMB(vp);
466 
467 	/* Set va_mask in caller */
468 
469 	/*
470 	 * Take type, mode, uid, gid from the smbfs node,
471 	 * which has have been updated by _getattr_otw.
472 	 */
473 	vap->va_type = vp->v_type;
474 	vap->va_mode = np->n_mode;
475 
476 	vap->va_uid = np->n_uid;
477 	vap->va_gid = np->n_gid;
478 
479 	vap->va_fsid = vp->v_vfsp->vfs_dev;
480 	vap->va_nodeid = np->n_ino;
481 	vap->va_nlink = 1;
482 
483 	/*
484 	 * Difference from NFS here:  We cache attributes as
485 	 * reported by the server, so r_attr.fa_size is the
486 	 * server's idea of the file size.  This is called
487 	 * for getattr, so we want to return the client's
488 	 * idea of the file size.  NFS deals with that in
489 	 * nfsgetattr(), the equivalent of our caller.
490 	 */
491 	vap->va_size = np->r_size;
492 
493 	/*
494 	 * Times.  Note, already converted from NT to
495 	 * Unix form (in the unmarshalling code).
496 	 */
497 	vap->va_atime = fa->fa_atime;
498 	vap->va_mtime = fa->fa_mtime;
499 	vap->va_ctime = fa->fa_ctime;
500 
501 	/*
502 	 * rdev, blksize, seq are made up.
503 	 * va_nblocks is 512 byte blocks.
504 	 */
505 	vap->va_rdev = vp->v_rdev;
506 	vap->va_blksize = MAXBSIZE;
507 	vap->va_nblocks = (fsblkcnt64_t)btod(np->r_attr.fa_allocsz);
508 	vap->va_seq = 0;
509 
510 	return (0);
511 }
512 
513 
514 /*
515  * SMB Client initialization and cleanup.
516  * Much of it is per-zone now.
517  */
518 
519 
520 /* ARGSUSED */
521 static void *
522 smbfs_zone_init(zoneid_t zoneid)
523 {
524 	smi_globals_t *smg;
525 
526 	smg = kmem_alloc(sizeof (*smg), KM_SLEEP);
527 	mutex_init(&smg->smg_lock, NULL, MUTEX_DEFAULT, NULL);
528 	list_create(&smg->smg_list, sizeof (smbmntinfo_t),
529 	    offsetof(smbmntinfo_t, smi_zone_node));
530 	smg->smg_destructor_called = B_FALSE;
531 	return (smg);
532 }
533 
534 /*
535  * Callback routine to tell all SMBFS mounts in the zone to stop creating new
536  * threads.  Existing threads should exit.
537  */
538 /* ARGSUSED */
539 static void
540 smbfs_zone_shutdown(zoneid_t zoneid, void *data)
541 {
542 	smi_globals_t *smg = data;
543 	smbmntinfo_t *smi;
544 
545 	ASSERT(smg != NULL);
546 again:
547 	mutex_enter(&smg->smg_lock);
548 	for (smi = list_head(&smg->smg_list); smi != NULL;
549 	    smi = list_next(&smg->smg_list, smi)) {
550 
551 		/*
552 		 * If we've done the shutdown work for this FS, skip.
553 		 * Once we go off the end of the list, we're done.
554 		 */
555 		if (smi->smi_flags & SMI_DEAD)
556 			continue;
557 
558 		/*
559 		 * We will do work, so not done.  Get a hold on the FS.
560 		 */
561 		VFS_HOLD(smi->smi_vfsp);
562 
563 		mutex_enter(&smi->smi_lock);
564 		smi->smi_flags |= SMI_DEAD;
565 		mutex_exit(&smi->smi_lock);
566 
567 		/*
568 		 * Drop lock and release FS, which may change list, then repeat.
569 		 * We're done when every mi has been done or the list is empty.
570 		 */
571 		mutex_exit(&smg->smg_lock);
572 		VFS_RELE(smi->smi_vfsp);
573 		goto again;
574 	}
575 	mutex_exit(&smg->smg_lock);
576 }
577 
578 static void
579 smbfs_zone_free_globals(smi_globals_t *smg)
580 {
581 	list_destroy(&smg->smg_list);	/* makes sure the list is empty */
582 	mutex_destroy(&smg->smg_lock);
583 	kmem_free(smg, sizeof (*smg));
584 
585 }
586 
587 /* ARGSUSED */
588 static void
589 smbfs_zone_destroy(zoneid_t zoneid, void *data)
590 {
591 	smi_globals_t *smg = data;
592 
593 	ASSERT(smg != NULL);
594 	mutex_enter(&smg->smg_lock);
595 	if (list_head(&smg->smg_list) != NULL) {
596 		/* Still waiting for VFS_FREEVFS() */
597 		smg->smg_destructor_called = B_TRUE;
598 		mutex_exit(&smg->smg_lock);
599 		return;
600 	}
601 	smbfs_zone_free_globals(smg);
602 }
603 
604 /*
605  * Add an SMBFS mount to the per-zone list of SMBFS mounts.
606  */
607 void
608 smbfs_zonelist_add(smbmntinfo_t *smi)
609 {
610 	smi_globals_t *smg;
611 
612 	smg = zone_getspecific(smi_list_key, smi->smi_zone_ref.zref_zone);
613 	mutex_enter(&smg->smg_lock);
614 	list_insert_head(&smg->smg_list, smi);
615 	mutex_exit(&smg->smg_lock);
616 }
617 
618 /*
619  * Remove an SMBFS mount from the per-zone list of SMBFS mounts.
620  */
621 void
622 smbfs_zonelist_remove(smbmntinfo_t *smi)
623 {
624 	smi_globals_t *smg;
625 
626 	smg = zone_getspecific(smi_list_key, smi->smi_zone_ref.zref_zone);
627 	mutex_enter(&smg->smg_lock);
628 	list_remove(&smg->smg_list, smi);
629 	/*
630 	 * We can be called asynchronously by VFS_FREEVFS() after the zone
631 	 * shutdown/destroy callbacks have executed; if so, clean up the zone's
632 	 * smi_globals.
633 	 */
634 	if (list_head(&smg->smg_list) == NULL &&
635 	    smg->smg_destructor_called == B_TRUE) {
636 		smbfs_zone_free_globals(smg);
637 		return;
638 	}
639 	mutex_exit(&smg->smg_lock);
640 }
641 
642 #ifdef	lint
643 #define	NEED_SMBFS_CALLBACKS	1
644 #endif
645 
646 #ifdef NEED_SMBFS_CALLBACKS
647 /*
648  * Call-back hooks for netsmb, in case we want them.
649  * Apple's VFS wants them.  We may not need them.
650  */
651 /*ARGSUSED*/
652 static void smbfs_dead(smb_share_t *ssp)
653 {
654 	/*
655 	 * Walk the mount list, finding all mounts
656 	 * using this share...
657 	 */
658 }
659 
660 /*ARGSUSED*/
661 static void smbfs_cb_nop(smb_share_t *ss)
662 {
663 	/* no-op */
664 }
665 
666 smb_fscb_t smbfs_cb = {
667 	.fscb_disconn	= smbfs_dead,
668 	.fscb_connect	= smbfs_cb_nop,
669 	.fscb_down	= smbfs_cb_nop,
670 	.fscb_up	= smbfs_cb_nop };
671 
672 #endif /* NEED_SMBFS_CALLBACKS */
673 
674 /*
675  * SMBFS Client initialization routine.  This routine should only be called
676  * once.  It performs the following tasks:
677  *      - Initalize all global locks
678  *      - Call sub-initialization routines (localize access to variables)
679  */
680 int
681 smbfs_clntinit(void)
682 {
683 
684 	zone_key_create(&smi_list_key, smbfs_zone_init, smbfs_zone_shutdown,
685 	    smbfs_zone_destroy);
686 #ifdef NEED_SMBFS_CALLBACKS
687 	(void) smb_fscb_set(&smbfs_cb);
688 #endif /* NEED_SMBFS_CALLBACKS */
689 	return (0);
690 }
691 
692 /*
693  * This routine is called when the modunload is called. This will cleanup
694  * the previously allocated/initialized nodes.
695  */
696 void
697 smbfs_clntfini(void)
698 {
699 #ifdef NEED_SMBFS_CALLBACKS
700 	(void) smb_fscb_set(NULL);
701 #endif /* NEED_SMBFS_CALLBACKS */
702 	(void) zone_key_delete(smi_list_key);
703 }
704