xref: /illumos-gate/usr/src/uts/common/fs/nfs/nfs_common.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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  * Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011 Bayard G. Bell. All rights reserved.
24  * Copyright 2013 Joyent, Inc. All rights reserved.
25  */
26 
27 /*
28  *	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
29  *		All rights reserved.
30  */
31 
32 #include <sys/errno.h>
33 #include <sys/param.h>
34 #include <sys/types.h>
35 #include <sys/user.h>
36 #include <sys/stat.h>
37 #include <sys/time.h>
38 #include <sys/utsname.h>
39 #include <sys/vfs.h>
40 #include <sys/vfs_opreg.h>
41 #include <sys/vnode.h>
42 #include <sys/pathname.h>
43 #include <sys/bootconf.h>
44 #include <fs/fs_subr.h>
45 #include <rpc/types.h>
46 #include <nfs/nfs.h>
47 #include <nfs/nfs4.h>
48 #include <nfs/nfs_clnt.h>
49 #include <nfs/rnode.h>
50 #include <nfs/mount.h>
51 #include <nfs/nfssys.h>
52 #include <sys/debug.h>
53 #include <sys/cmn_err.h>
54 #include <sys/file.h>
55 #include <sys/fcntl.h>
56 #include <sys/zone.h>
57 
58 /*
59  * This is the loadable module wrapper.
60  */
61 #include <sys/systm.h>
62 #include <sys/modctl.h>
63 #include <sys/syscall.h>
64 #include <sys/ddi.h>
65 
66 #include <rpc/types.h>
67 #include <rpc/auth.h>
68 #include <rpc/clnt.h>
69 #include <rpc/svc.h>
70 
71 /*
72  * The pseudo NFS filesystem to allow diskless booting to dynamically
73  * mount either a NFS V2, NFS V3, or NFS V4 filesystem.  This only implements
74  * the VFS_MOUNTROOT op and is only intended to be used by the
75  * diskless booting code until the real root filesystem is mounted.
76  * Nothing else should ever call this!
77  *
78  * The strategy is that if the initial rootfs type is set to "nfsdyn"
79  * by loadrootmodules() this filesystem is called to mount the
80  * root filesystem.  It first attempts to mount a V4 filesystem, and if that
81  * fails due to an RPC version mismatch it tries V3 and finally V2.
82  * Once the real mount succeeds the vfsops and rootfs name are changed
83  * to reflect the real filesystem type.
84  */
85 static int nfsdyninit(int, char *);
86 static int nfsdyn_mountroot(vfs_t *, whymountroot_t);
87 
88 vfsops_t *nfsdyn_vfsops;
89 
90 /*
91  * The following data structures are used to configure the NFS
92  * system call, the NFS Version 2 client VFS, and the NFS Version
93  * 3 client VFS into the system.  The NFS Version 4 structures are defined in
94  * nfs4_common.c
95  */
96 
97 /*
98  * The NFS system call.
99  */
100 static struct sysent nfssysent = {
101 	2,
102 	SE_32RVAL1 | SE_ARGC | SE_NOUNLOAD,
103 	nfssys
104 };
105 
106 static struct modlsys modlsys = {
107 	&mod_syscallops,
108 	"NFS syscall, client, and common",
109 	&nfssysent
110 };
111 
112 #ifdef _SYSCALL32_IMPL
113 static struct modlsys modlsys32 = {
114 	&mod_syscallops32,
115 	"NFS syscall, client, and common (32-bit)",
116 	&nfssysent
117 };
118 #endif /* _SYSCALL32_IMPL */
119 
120 /*
121  * The NFS Dynamic client VFS.
122  */
123 static vfsdef_t vfw = {
124 	VFSDEF_VERSION,
125 	"nfsdyn",
126 	nfsdyninit,
127 	0,
128 	NULL
129 };
130 
131 static struct modlfs modlfs = {
132 	&mod_fsops,
133 	"network filesystem",
134 	&vfw
135 };
136 
137 /*
138  * The NFS Version 2 client VFS.
139  */
140 static vfsdef_t vfw2 = {
141 	VFSDEF_VERSION,
142 	"nfs",
143 	nfsinit,
144 	VSW_CANREMOUNT|VSW_NOTZONESAFE|VSW_STATS,
145 	NULL
146 };
147 
148 static struct modlfs modlfs2 = {
149 	&mod_fsops,
150 	"network filesystem version 2",
151 	&vfw2
152 };
153 
154 /*
155  * The NFS Version 3 client VFS.
156  */
157 static vfsdef_t vfw3 = {
158 	VFSDEF_VERSION,
159 	"nfs3",
160 	nfs3init,
161 	VSW_CANREMOUNT|VSW_NOTZONESAFE|VSW_STATS,
162 	NULL
163 };
164 
165 static struct modlfs modlfs3 = {
166 	&mod_fsops,
167 	"network filesystem version 3",
168 	&vfw3
169 };
170 
171 extern struct modlfs modlfs4;
172 
173 /*
174  * We have too many linkage structures so we define our own XXX
175  */
176 struct modlinkage_big {
177 	int		ml_rev;		/* rev of loadable modules system */
178 	void		*ml_linkage[7];	/* NULL terminated list of */
179 					/* linkage structures */
180 };
181 
182 /*
183  * All of the module configuration linkages required to configure
184  * the system call and client VFS's into the system.
185  */
186 static struct modlinkage_big modlinkage = {
187 	MODREV_1,
188 	&modlsys,
189 #ifdef _SYSCALL32_IMPL
190 	&modlsys32,
191 #endif
192 	&modlfs,
193 	&modlfs2,
194 	&modlfs3,
195 	&modlfs4,
196 	NULL
197 };
198 
199 /*
200  * This routine is invoked automatically when the kernel module
201  * containing this routine is loaded.  This allows module specific
202  * initialization to be done when the module is loaded.
203  */
204 int
205 _init(void)
206 {
207 	int status;
208 
209 	if ((status = nfs_clntinit()) != 0) {
210 		cmn_err(CE_WARN, "_init: nfs_clntinit failed");
211 		return (status);
212 	}
213 
214 	/*
215 	 * Create the version specific kstats.
216 	 *
217 	 * PSARC 2001/697 Contract Private Interface
218 	 * All nfs kstats are under SunMC contract
219 	 * Please refer to the PSARC listed above and contact
220 	 * SunMC before making any changes!
221 	 *
222 	 * Changes must be reviewed by Solaris File Sharing
223 	 * Changes must be communicated to contract-2001-697@sun.com
224 	 *
225 	 */
226 
227 	zone_key_create(&nfsstat_zone_key, nfsstat_zone_init, NULL,
228 	    nfsstat_zone_fini);
229 	status = mod_install((struct modlinkage *)&modlinkage);
230 
231 	if (status)  {
232 		(void) zone_key_delete(nfsstat_zone_key);
233 
234 		/*
235 		 * Failed to install module, cleanup previous
236 		 * initialization work.
237 		 */
238 		nfs_clntfini();
239 
240 		/*
241 		 * Clean up work performed indirectly by mod_installfs()
242 		 * as a result of our call to mod_install().
243 		 */
244 		nfs4fini();
245 		nfs3fini();
246 		nfsfini();
247 	}
248 	return (status);
249 }
250 
251 int
252 _fini(void)
253 {
254 	/* Don't allow module to be unloaded */
255 	return (EBUSY);
256 }
257 
258 int
259 _info(struct modinfo *modinfop)
260 {
261 	return (mod_info((struct modlinkage *)&modlinkage, modinfop));
262 }
263 
264 /*
265  * General utilities
266  */
267 
268 /*
269  * Returns the preferred transfer size in bytes based on
270  * what network interfaces are available.
271  */
272 int
273 nfstsize(void)
274 {
275 	/*
276 	 * For the moment, just return NFS_MAXDATA until we can query the
277 	 * appropriate transport.
278 	 */
279 	return (NFS_MAXDATA);
280 }
281 
282 /*
283  * Returns the preferred transfer size in bytes based on
284  * what network interfaces are available.
285  */
286 
287 /* this should reflect the largest transfer size possible */
288 static int nfs3_max_transfer_size = 1024 * 1024;
289 
290 int
291 nfs3tsize(void)
292 {
293 	/*
294 	 * For the moment, just return nfs3_max_transfer_size until we
295 	 * can query the appropriate transport.
296 	 */
297 	return (nfs3_max_transfer_size);
298 }
299 
300 static uint_t nfs3_max_transfer_size_clts = 32 * 1024;
301 static uint_t nfs3_max_transfer_size_cots = 1024 * 1024;
302 static uint_t nfs3_max_transfer_size_rdma = 1024 * 1024;
303 
304 uint_t
305 nfs3_tsize(struct knetconfig *knp)
306 {
307 
308 	if (knp->knc_semantics == NC_TPI_COTS_ORD ||
309 	    knp->knc_semantics == NC_TPI_COTS)
310 		return (nfs3_max_transfer_size_cots);
311 	if (knp->knc_semantics == NC_TPI_RDMA)
312 		return (nfs3_max_transfer_size_rdma);
313 	return (nfs3_max_transfer_size_clts);
314 }
315 
316 uint_t
317 rfs3_tsize(struct svc_req *req)
318 {
319 
320 	if (req->rq_xprt->xp_type == T_COTS_ORD ||
321 	    req->rq_xprt->xp_type == T_COTS)
322 		return (nfs3_max_transfer_size_cots);
323 	if (req->rq_xprt->xp_type == T_RDMA)
324 		return (nfs3_max_transfer_size_rdma);
325 	return (nfs3_max_transfer_size_clts);
326 }
327 
328 /* ARGSUSED */
329 static int
330 nfsdyninit(int fstyp, char *name)
331 {
332 	static const fs_operation_def_t nfsdyn_vfsops_template[] = {
333 		VFSNAME_MOUNTROOT, { .vfs_mountroot = nfsdyn_mountroot },
334 		NULL, NULL
335 	};
336 	int error;
337 
338 	error = vfs_setfsops(fstyp, nfsdyn_vfsops_template, &nfsdyn_vfsops);
339 	if (error != 0)
340 		return (error);
341 
342 	return (0);
343 }
344 
345 /* ARGSUSED */
346 static int
347 nfsdyn_mountroot(vfs_t *vfsp, whymountroot_t why)
348 {
349 	char root_hostname[SYS_NMLN+1];
350 	struct servinfo *svp;
351 	int error;
352 	int vfsflags;
353 	char *root_path;
354 	struct pathname pn;
355 	char *name;
356 	static char token[10];
357 	struct nfs_args args;		/* nfs mount arguments */
358 
359 	bzero(&args, sizeof (args));
360 
361 	/* do this BEFORE getfile which causes xid stamps to be initialized */
362 	clkset(-1L);		/* hack for now - until we get time svc? */
363 
364 	if (why == ROOT_REMOUNT) {
365 		/*
366 		 * Shouldn't happen.
367 		 */
368 		panic("nfs3_mountroot: why == ROOT_REMOUNT\n");
369 	}
370 
371 	if (why == ROOT_UNMOUNT) {
372 		/*
373 		 * Nothing to do for NFS.
374 		 */
375 		return (0);
376 	}
377 
378 	/*
379 	 * why == ROOT_INIT
380 	 */
381 
382 	name = token;
383 	*name = 0;
384 	getfsname("root", name, sizeof (token));
385 
386 	pn_alloc(&pn);
387 	root_path = pn.pn_path;
388 
389 	svp = kmem_zalloc(sizeof (*svp), KM_SLEEP);
390 	mutex_init(&svp->sv_lock, NULL, MUTEX_DEFAULT, NULL);
391 	svp->sv_knconf = kmem_zalloc(sizeof (*svp->sv_knconf), KM_SLEEP);
392 	svp->sv_knconf->knc_protofmly = kmem_alloc(KNC_STRSIZE, KM_SLEEP);
393 	svp->sv_knconf->knc_proto = kmem_alloc(KNC_STRSIZE, KM_SLEEP);
394 
395 	/*
396 	 * First try version 4
397 	 */
398 	vfs_setops(vfsp, nfs4_vfsops);
399 	args.addr = &svp->sv_addr;
400 	args.fh = (char *)&svp->sv_fhandle;
401 	args.knconf = svp->sv_knconf;
402 	args.hostname = root_hostname;
403 	vfsflags = 0;
404 
405 	if (error = mount_root(*name ? name : "root", root_path, NFS_V4,
406 	    &args, &vfsflags)) {
407 		if (error != EPROTONOSUPPORT) {
408 			nfs_cmn_err(error, CE_WARN,
409 			    "Unable to mount NFS root filesystem: %m");
410 			sv_free(svp);
411 			pn_free(&pn);
412 			vfs_setops(vfsp, nfsdyn_vfsops);
413 			return (error);
414 		}
415 
416 		/*
417 		 * Then try version 3
418 		 */
419 		bzero(&args, sizeof (args));
420 		vfs_setops(vfsp, nfs3_vfsops);
421 		args.addr = &svp->sv_addr;
422 		args.fh = (char *)&svp->sv_fhandle;
423 		args.knconf = svp->sv_knconf;
424 		args.hostname = root_hostname;
425 		vfsflags = 0;
426 
427 		if (error = mount_root(*name ? name : "root", root_path,
428 		    NFS_V3, &args, &vfsflags)) {
429 			if (error != EPROTONOSUPPORT) {
430 				nfs_cmn_err(error, CE_WARN,
431 				    "Unable to mount NFS root filesystem: %m");
432 				sv_free(svp);
433 				pn_free(&pn);
434 				vfs_setops(vfsp, nfsdyn_vfsops);
435 				return (error);
436 			}
437 
438 			/*
439 			 * Finally, try version 2
440 			 */
441 			bzero(&args, sizeof (args));
442 			args.addr = &svp->sv_addr;
443 			args.fh = (char *)&svp->sv_fhandle.fh_buf;
444 			args.knconf = svp->sv_knconf;
445 			args.hostname = root_hostname;
446 			vfsflags = 0;
447 
448 			vfs_setops(vfsp, nfs_vfsops);
449 
450 			if (error = mount_root(*name ? name : "root",
451 			    root_path, NFS_VERSION, &args, &vfsflags)) {
452 				nfs_cmn_err(error, CE_WARN,
453 				    "Unable to mount NFS root filesystem: %m");
454 				sv_free(svp);
455 				pn_free(&pn);
456 				vfs_setops(vfsp, nfsdyn_vfsops);
457 				return (error);
458 			}
459 		}
460 	}
461 
462 	sv_free(svp);
463 	pn_free(&pn);
464 	return (VFS_MOUNTROOT(vfsp, why));
465 }
466 
467 int
468 nfs_setopts(vnode_t *vp, model_t model, struct nfs_args *buf)
469 {
470 	mntinfo_t *mi;			/* mount info, pointed at by vfs */
471 	STRUCT_HANDLE(nfs_args, args);
472 	int flags;
473 
474 #ifdef lint
475 	model = model;
476 #endif
477 
478 	STRUCT_SET_HANDLE(args, model, buf);
479 
480 	flags = STRUCT_FGET(args, flags);
481 
482 	/*
483 	 * Set option fields in mount info record
484 	 */
485 	mi = VTOMI(vp);
486 
487 	if (flags & NFSMNT_NOAC) {
488 		mi->mi_flags |= MI_NOAC;
489 		PURGE_ATTRCACHE(vp);
490 	}
491 	if (flags & NFSMNT_NOCTO)
492 		mi->mi_flags |= MI_NOCTO;
493 	if (flags & NFSMNT_LLOCK)
494 		mi->mi_flags |= MI_LLOCK;
495 	if (flags & NFSMNT_GRPID)
496 		mi->mi_flags |= MI_GRPID;
497 	if (flags & NFSMNT_RETRANS) {
498 		if (STRUCT_FGET(args, retrans) < 0)
499 			return (EINVAL);
500 		mi->mi_retrans = STRUCT_FGET(args, retrans);
501 	}
502 	if (flags & NFSMNT_TIMEO) {
503 		if (STRUCT_FGET(args, timeo) <= 0)
504 			return (EINVAL);
505 		mi->mi_timeo = STRUCT_FGET(args, timeo);
506 		/*
507 		 * The following scales the standard deviation and
508 		 * and current retransmission timer to match the
509 		 * initial value for the timeout specified.
510 		 */
511 		mi->mi_timers[NFS_CALLTYPES].rt_deviate =
512 		    (mi->mi_timeo * hz * 2) / 5;
513 		mi->mi_timers[NFS_CALLTYPES].rt_rtxcur =
514 		    mi->mi_timeo * hz / 10;
515 	}
516 	if (flags & NFSMNT_RSIZE) {
517 		if (STRUCT_FGET(args, rsize) <= 0)
518 			return (EINVAL);
519 		mi->mi_tsize = MIN(mi->mi_tsize, STRUCT_FGET(args, rsize));
520 		mi->mi_curread = MIN(mi->mi_curread, mi->mi_tsize);
521 	}
522 	if (flags & NFSMNT_WSIZE) {
523 		if (STRUCT_FGET(args, wsize) <= 0)
524 			return (EINVAL);
525 		mi->mi_stsize = MIN(mi->mi_stsize, STRUCT_FGET(args, wsize));
526 		mi->mi_curwrite = MIN(mi->mi_curwrite, mi->mi_stsize);
527 	}
528 	if (flags & NFSMNT_ACREGMIN) {
529 		if (STRUCT_FGET(args, acregmin) < 0)
530 			mi->mi_acregmin = ACMINMAX;
531 		else
532 			mi->mi_acregmin = MIN(STRUCT_FGET(args, acregmin),
533 			    ACMINMAX);
534 		mi->mi_acregmin = SEC2HR(mi->mi_acregmin);
535 	}
536 	if (flags & NFSMNT_ACREGMAX) {
537 		if (STRUCT_FGET(args, acregmax) < 0)
538 			mi->mi_acregmax = ACMAXMAX;
539 		else
540 			mi->mi_acregmax = MIN(STRUCT_FGET(args, acregmax),
541 			    ACMAXMAX);
542 		mi->mi_acregmax = SEC2HR(mi->mi_acregmax);
543 	}
544 	if (flags & NFSMNT_ACDIRMIN) {
545 		if (STRUCT_FGET(args, acdirmin) < 0)
546 			mi->mi_acdirmin = ACMINMAX;
547 		else
548 			mi->mi_acdirmin = MIN(STRUCT_FGET(args, acdirmin),
549 			    ACMINMAX);
550 		mi->mi_acdirmin = SEC2HR(mi->mi_acdirmin);
551 	}
552 	if (flags & NFSMNT_ACDIRMAX) {
553 		if (STRUCT_FGET(args, acdirmax) < 0)
554 			mi->mi_acdirmax = ACMAXMAX;
555 		else
556 			mi->mi_acdirmax = MIN(STRUCT_FGET(args, acdirmax),
557 			    ACMAXMAX);
558 		mi->mi_acdirmax = SEC2HR(mi->mi_acdirmax);
559 	}
560 
561 	if (flags & NFSMNT_LOOPBACK)
562 		mi->mi_flags |= MI_LOOPBACK;
563 
564 	return (0);
565 }
566 
567 /*
568  * Set or Clear direct I/O flag
569  * VOP_RWLOCK() is held for write access to prevent a race condition
570  * which would occur if a process is in the middle of a write when
571  * directio flag gets set. It is possible that all pages may not get flushed.
572  */
573 
574 /* ARGSUSED */
575 int
576 nfs_directio(vnode_t *vp, int cmd, cred_t *cr)
577 {
578 	int	error = 0;
579 	rnode_t	*rp;
580 
581 	rp = VTOR(vp);
582 
583 	if (cmd == DIRECTIO_ON) {
584 
585 		if (rp->r_flags & RDIRECTIO)
586 			return (0);
587 
588 		/*
589 		 * Flush the page cache.
590 		 */
591 
592 		(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
593 
594 		if (rp->r_flags & RDIRECTIO) {
595 			VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
596 			return (0);
597 		}
598 
599 		if (vn_has_cached_data(vp) &&
600 		    ((rp->r_flags & RDIRTY) || rp->r_awcount > 0)) {
601 			error = VOP_PUTPAGE(vp, (offset_t)0, (uint_t)0,
602 			    B_INVAL, cr, NULL);
603 			if (error) {
604 				if (error == ENOSPC || error == EDQUOT) {
605 					mutex_enter(&rp->r_statelock);
606 					if (!rp->r_error)
607 						rp->r_error = error;
608 					mutex_exit(&rp->r_statelock);
609 				}
610 				VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
611 				return (error);
612 			}
613 		}
614 
615 		mutex_enter(&rp->r_statelock);
616 		rp->r_flags |= RDIRECTIO;
617 		mutex_exit(&rp->r_statelock);
618 		VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
619 		return (0);
620 	}
621 
622 	if (cmd == DIRECTIO_OFF) {
623 		mutex_enter(&rp->r_statelock);
624 		rp->r_flags &= ~RDIRECTIO;	/* disable direct mode */
625 		mutex_exit(&rp->r_statelock);
626 		return (0);
627 	}
628 
629 	return (EINVAL);
630 }
631