coda_vfsops.c revision 138478 
1/*
2 *             Coda: an Experimental Distributed File System
3 *                              Release 3.1
4 *
5 *           Copyright (c) 1987-1998 Carnegie Mellon University
6 *                          All Rights Reserved
7 *
8 * Permission  to  use, copy, modify and distribute this software and its
9 * documentation is hereby granted,  provided  that  both  the  copyright
10 * notice  and  this  permission  notice  appear  in  all  copies  of the
11 * software, derivative works or  modified  versions,  and  any  portions
12 * thereof, and that both notices appear in supporting documentation, and
13 * that credit is given to Carnegie Mellon University  in  all  documents
14 * and publicity pertaining to direct or indirect use of this code or its
15 * derivatives.
16 *
17 * CODA IS AN EXPERIMENTAL SOFTWARE SYSTEM AND IS  KNOWN  TO  HAVE  BUGS,
18 * SOME  OF  WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON ALLOWS
19 * FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.   CARNEGIE  MELLON
20 * DISCLAIMS  ANY  LIABILITY  OF  ANY  KIND  FOR  ANY  DAMAGES WHATSOEVER
21 * RESULTING DIRECTLY OR INDIRECTLY FROM THE USE OF THIS SOFTWARE  OR  OF
22 * ANY DERIVATIVE WORK.
23 *
24 * Carnegie  Mellon  encourages  users  of  this  software  to return any
25 * improvements or extensions that  they  make,  and  to  grant  Carnegie
26 * Mellon the rights to redistribute these changes without encumbrance.
27 *
28 *  	@(#) src/sys/cfs/coda_vfsops.c,v 1.1.1.1 1998/08/29 21:14:52 rvb Exp $
29 */
30/*
31 * Mach Operating System
32 * Copyright (c) 1989 Carnegie-Mellon University
33 * All rights reserved.  The CMU software License Agreement specifies
34 * the terms and conditions for use and redistribution.
35 */
36
37/*
38 * This code was written for the Coda filesystem at Carnegie Mellon
39 * University.  Contributers include David Steere, James Kistler, and
40 * M. Satyanarayanan.
41 */
42
43#include <sys/cdefs.h>
44__FBSDID("$FreeBSD: head/sys/fs/coda/coda_vfsops.c 138478 2004-12-06 19:46:02Z phk $");
45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/conf.h>
49#include <sys/kernel.h>
50#include <sys/lock.h>
51#include <sys/malloc.h>
52#include <sys/mount.h>
53#include <sys/namei.h>
54#include <sys/proc.h>
55
56#include <coda/coda.h>
57#include <coda/cnode.h>
58#include <coda/coda_vfsops.h>
59#include <coda/coda_venus.h>
60#include <coda/coda_subr.h>
61#include <coda/coda_opstats.h>
62
63MALLOC_DEFINE(M_CODA, "CODA storage", "Various Coda Structures");
64
65int codadebug = 0;
66int coda_vfsop_print_entry = 0;
67#define ENTRY    if(coda_vfsop_print_entry) myprintf(("Entered %s\n",__func__))
68
69struct vnode *coda_ctlvp;
70
71/* structure to keep statistics of internally generated/satisfied calls */
72
73struct coda_op_stats coda_vfsopstats[CODA_VFSOPS_SIZE];
74
75#define MARK_ENTRY(op) (coda_vfsopstats[op].entries++)
76#define MARK_INT_SAT(op) (coda_vfsopstats[op].sat_intrn++)
77#define MARK_INT_FAIL(op) (coda_vfsopstats[op].unsat_intrn++)
78#define MRAK_INT_GEN(op) (coda_vfsopstats[op].gen_intrn++)
79
80extern int coda_nc_initialized;     /* Set if cache has been initialized */
81extern int vc_nb_open(struct cdev *, int, int, struct thread *);
82
83int
84coda_vfsopstats_init(void)
85{
86	register int i;
87
88	for (i=0;i<CODA_VFSOPS_SIZE;i++) {
89		coda_vfsopstats[i].opcode = i;
90		coda_vfsopstats[i].entries = 0;
91		coda_vfsopstats[i].sat_intrn = 0;
92		coda_vfsopstats[i].unsat_intrn = 0;
93		coda_vfsopstats[i].gen_intrn = 0;
94	}
95
96	return 0;
97}
98
99static const char *coda_opts[] = { "from", NULL };
100/*
101 * cfs mount vfsop
102 * Set up mount info record and attach it to vfs struct.
103 */
104/*ARGSUSED*/
105int
106coda_mount(struct mount *vfsp, struct thread *td)
107{
108    struct vnode *dvp;
109    struct cnode *cp;
110    struct cdev *dev;
111    struct coda_mntinfo *mi;
112    struct vnode *rootvp;
113    CodaFid rootfid = INVAL_FID;
114    CodaFid ctlfid = CTL_FID;
115    int error;
116    struct nameidata ndp;
117    ENTRY;
118    char *from;
119
120    if (vfs_filteropt(vfsp->mnt_optnew, coda_opts))
121	return (EINVAL);
122
123    from = vfs_getopts(vfsp->mnt_optnew, "from", &error);
124    if (error)
125	return (error);
126
127    coda_vfsopstats_init();
128    coda_vnodeopstats_init();
129
130    MARK_ENTRY(CODA_MOUNT_STATS);
131    if (CODA_MOUNTED(vfsp)) {
132	MARK_INT_FAIL(CODA_MOUNT_STATS);
133	return(EBUSY);
134    }
135
136    /* Validate mount device.  Similar to getmdev(). */
137    NDINIT(&ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, from, td);
138    error = namei(&ndp);
139    dvp = ndp.ni_vp;
140
141    if (error) {
142	MARK_INT_FAIL(CODA_MOUNT_STATS);
143	return (error);
144    }
145    if (dvp->v_type != VCHR) {
146	MARK_INT_FAIL(CODA_MOUNT_STATS);
147	vrele(dvp);
148	NDFREE(&ndp, NDF_ONLY_PNBUF);
149	return(ENXIO);
150    }
151    dev = dvp->v_rdev;
152    vrele(dvp);
153    NDFREE(&ndp, NDF_ONLY_PNBUF);
154
155    /*
156     * See if the device table matches our expectations.
157     */
158    if (dev->si_devsw->d_open != vc_nb_open)
159    {
160	MARK_INT_FAIL(CODA_MOUNT_STATS);
161	return(ENXIO);
162    }
163
164    /*
165     * Initialize the mount record and link it to the vfs struct
166     */
167    mi = dev2coda_mntinfo(dev);
168
169    if (!VC_OPEN(&mi->mi_vcomm)) {
170	MARK_INT_FAIL(CODA_MOUNT_STATS);
171	return(ENODEV);
172    }
173
174    /* No initialization (here) of mi_vcomm! */
175    vfsp->mnt_data = (qaddr_t)mi;
176    vfs_getnewfsid (vfsp);
177
178    mi->mi_vfsp = vfsp;
179    mi->mi_started = 0;			/* XXX See coda_root() */
180
181    /*
182     * Make a root vnode to placate the Vnode interface, but don't
183     * actually make the CODA_ROOT call to venus until the first call
184     * to coda_root in case a server is down while venus is starting.
185     */
186    cp = make_coda_node(&rootfid, vfsp, VDIR);
187    rootvp = CTOV(cp);
188    rootvp->v_vflag |= VV_ROOT;
189
190/*  cp = make_coda_node(&ctlfid, vfsp, VCHR);
191    The above code seems to cause a loop in the cnode links.
192    I don't totally understand when it happens, it is caught
193    when closing down the system.
194 */
195    cp = make_coda_node(&ctlfid, 0, VCHR);
196
197    coda_ctlvp = CTOV(cp);
198
199    /* Add vfs and rootvp to chain of vfs hanging off mntinfo */
200    mi->mi_vfsp = vfsp;
201    mi->mi_rootvp = rootvp;
202
203    vfs_mountedfrom(vfsp, from);
204    /* error is currently guaranteed to be zero, but in case some
205       code changes... */
206    CODADEBUG(1,
207	     myprintf(("coda_omount returned %d\n",error)););
208    if (error)
209	MARK_INT_FAIL(CODA_MOUNT_STATS);
210    else
211	MARK_INT_SAT(CODA_MOUNT_STATS);
212
213    return(error);
214}
215
216int
217coda_unmount(vfsp, mntflags, td)
218    struct mount *vfsp;
219    int mntflags;
220    struct thread *td;
221{
222    struct coda_mntinfo *mi = vftomi(vfsp);
223    int active, error = 0;
224
225    ENTRY;
226    MARK_ENTRY(CODA_UMOUNT_STATS);
227    if (!CODA_MOUNTED(vfsp)) {
228	MARK_INT_FAIL(CODA_UMOUNT_STATS);
229	return(EINVAL);
230    }
231
232    if (mi->mi_vfsp == vfsp) {	/* We found the victim */
233	if (!IS_UNMOUNTING(VTOC(mi->mi_rootvp)))
234	    return (EBUSY); 	/* Venus is still running */
235
236#ifdef	DEBUG
237	printf("coda_unmount: ROOT: vp %p, cp %p\n", mi->mi_rootvp, VTOC(mi->mi_rootvp));
238#endif
239	vrele(mi->mi_rootvp);
240	active = coda_kill(vfsp, NOT_DOWNCALL);
241	ASSERT_VOP_LOCKED(mi->mi_rootvp, "coda_unmount");
242	mi->mi_rootvp->v_vflag &= ~VV_ROOT;
243	error = vflush(mi->mi_vfsp, 0, FORCECLOSE, td);
244#ifdef CODA_VERBOSE
245	printf("coda_unmount: active = %d, vflush active %d\n", active, error);
246#endif
247	error = 0;
248	/* I'm going to take this out to allow lookups to go through. I'm
249	 * not sure it's important anyway. -- DCS 2/2/94
250	 */
251	/* vfsp->VFS_DATA = NULL; */
252
253	/* No more vfsp's to hold onto */
254	mi->mi_vfsp = NULL;
255	mi->mi_rootvp = NULL;
256
257	if (error)
258	    MARK_INT_FAIL(CODA_UMOUNT_STATS);
259	else
260	    MARK_INT_SAT(CODA_UMOUNT_STATS);
261
262	return(error);
263    }
264    return (EINVAL);
265}
266
267/*
268 * find root of cfs
269 */
270int
271coda_root(vfsp, vpp, td)
272	struct mount *vfsp;
273	struct vnode **vpp;
274	struct thread *td;
275{
276    struct coda_mntinfo *mi = vftomi(vfsp);
277    struct vnode **result;
278    int error;
279    struct proc *p = td->td_proc;
280    CodaFid VFid;
281    static const CodaFid invalfid = INVAL_FID;
282
283    ENTRY;
284    MARK_ENTRY(CODA_ROOT_STATS);
285    result = NULL;
286
287    if (vfsp == mi->mi_vfsp) {
288	/*
289	 * Cache the root across calls. We only need to pass the request
290	 * on to Venus if the root vnode is the dummy we installed in
291	 * coda_omount() with all c_fid members zeroed.
292	 *
293	 * XXX In addition, if we are called between coda_omount() and
294	 * coda_start(), we assume that the request is from vfs_omount()
295	 * (before the call to checkdirs()) and return the dummy root
296	 * node to avoid a deadlock. This bug is fixed in the Coda CVS
297	 * repository but not in any released versions as of 6 Mar 2003.
298	 */
299	if (memcmp(&VTOC(mi->mi_rootvp)->c_fid, &invalfid,
300	    sizeof(CodaFid)) != 0 || mi->mi_started == 0)
301	    { /* Found valid root. */
302		*vpp = mi->mi_rootvp;
303		/* On Mach, this is vref.  On NetBSD, VOP_LOCK */
304#if	1
305		vref(*vpp);
306		vn_lock(*vpp, LK_EXCLUSIVE, td);
307#else
308		vget(*vpp, LK_EXCLUSIVE, td);
309#endif
310		MARK_INT_SAT(CODA_ROOT_STATS);
311		return(0);
312	    }
313    }
314
315    error = venus_root(vftomi(vfsp), td->td_ucred, p, &VFid);
316
317    if (!error) {
318	/*
319	 * Save the new rootfid in the cnode, and rehash the cnode into the
320	 * cnode hash with the new fid key.
321	 */
322	coda_unsave(VTOC(mi->mi_rootvp));
323	VTOC(mi->mi_rootvp)->c_fid = VFid;
324	coda_save(VTOC(mi->mi_rootvp));
325
326	*vpp = mi->mi_rootvp;
327#if	1
328	vref(*vpp);
329	vn_lock(*vpp, LK_EXCLUSIVE, td);
330#else
331	vget(*vpp, LK_EXCLUSIVE, td);
332#endif
333
334	MARK_INT_SAT(CODA_ROOT_STATS);
335	goto exit;
336    } else if (error == ENODEV || error == EINTR) {
337	/* Gross hack here! */
338	/*
339	 * If Venus fails to respond to the CODA_ROOT call, coda_call returns
340	 * ENODEV. Return the uninitialized root vnode to allow vfs
341	 * operations such as unmount to continue. Without this hack,
342	 * there is no way to do an unmount if Venus dies before a
343	 * successful CODA_ROOT call is done. All vnode operations
344	 * will fail.
345	 */
346	*vpp = mi->mi_rootvp;
347#if	1
348	vref(*vpp);
349	vn_lock(*vpp, LK_EXCLUSIVE, td);
350#else
351	vget(*vpp, LK_EXCLUSIVE, td);
352#endif
353
354	MARK_INT_FAIL(CODA_ROOT_STATS);
355	error = 0;
356	goto exit;
357    } else {
358	CODADEBUG( CODA_ROOT, myprintf(("error %d in CODA_ROOT\n", error)); );
359	MARK_INT_FAIL(CODA_ROOT_STATS);
360
361	goto exit;
362    }
363
364 exit:
365    return(error);
366}
367
368int
369coda_start(mp, flags, td)
370	struct mount *mp;
371	int flags;
372	struct thread *td;
373{
374
375	/* XXX See coda_root(). */
376	vftomi(mp)->mi_started = 1;
377	return (0);
378}
379
380/*
381 * Get filesystem statistics.
382 */
383int
384coda_nb_statfs(vfsp, sbp, td)
385    register struct mount *vfsp;
386    struct statfs *sbp;
387    struct thread *td;
388{
389    ENTRY;
390/*  MARK_ENTRY(CODA_STATFS_STATS); */
391    if (!CODA_MOUNTED(vfsp)) {
392/*	MARK_INT_FAIL(CODA_STATFS_STATS);*/
393	return(EINVAL);
394    }
395
396    bzero(sbp, sizeof(struct statfs));
397    /* XXX - what to do about f_flags, others? --bnoble */
398    /* Below This is what AFS does
399    	#define NB_SFS_SIZ 0x895440
400     */
401    /* Note: Normal fs's have a bsize of 0x400 == 1024 */
402    sbp->f_type = vfsp->mnt_vfc->vfc_typenum;
403    sbp->f_bsize = 8192; /* XXX */
404    sbp->f_iosize = 8192; /* XXX */
405#define NB_SFS_SIZ 0x8AB75D
406    sbp->f_blocks = NB_SFS_SIZ;
407    sbp->f_bfree = NB_SFS_SIZ;
408    sbp->f_bavail = NB_SFS_SIZ;
409    sbp->f_files = NB_SFS_SIZ;
410    sbp->f_ffree = NB_SFS_SIZ;
411    bcopy((caddr_t)&(vfsp->mnt_stat.f_fsid), (caddr_t)&(sbp->f_fsid), sizeof (fsid_t));
412    snprintf(sbp->f_mntonname, sizeof(sbp->f_mntonname), "/coda");
413    snprintf(sbp->f_fstypename, sizeof(sbp->f_fstypename), "coda");
414/*  MARK_INT_SAT(CODA_STATFS_STATS); */
415    return(0);
416}
417
418/*
419 * Flush any pending I/O.
420 */
421int
422coda_sync(vfsp, waitfor, cred, td)
423    struct mount *vfsp;
424    int    waitfor;
425    struct ucred *cred;
426    struct thread *td;
427{
428    ENTRY;
429    MARK_ENTRY(CODA_SYNC_STATS);
430    MARK_INT_SAT(CODA_SYNC_STATS);
431    return(0);
432}
433
434/*
435 * fhtovp is now what vget used to be in 4.3-derived systems.  For
436 * some silly reason, vget is now keyed by a 32 bit ino_t, rather than
437 * a type-specific fid.
438 */
439int
440coda_fhtovp(vfsp, fhp, nam, vpp, exflagsp, creadanonp)
441    register struct mount *vfsp;
442    struct fid *fhp;
443    struct mbuf *nam;
444    struct vnode **vpp;
445    int *exflagsp;
446    struct ucred **creadanonp;
447{
448    struct cfid *cfid = (struct cfid *)fhp;
449    struct cnode *cp = 0;
450    int error;
451    struct thread *td = curthread; /* XXX -mach */
452    struct proc *p = td->td_proc;
453    CodaFid VFid;
454    int vtype;
455
456    ENTRY;
457
458    MARK_ENTRY(CODA_VGET_STATS);
459    /* Check for vget of control object. */
460    if (IS_CTL_FID(&cfid->cfid_fid)) {
461	*vpp = coda_ctlvp;
462	vref(coda_ctlvp);
463	MARK_INT_SAT(CODA_VGET_STATS);
464	return(0);
465    }
466
467    error = venus_fhtovp(vftomi(vfsp), &cfid->cfid_fid, td->td_ucred, p, &VFid, &vtype);
468
469    if (error) {
470	CODADEBUG(CODA_VGET, myprintf(("vget error %d\n",error));)
471	    *vpp = (struct vnode *)0;
472    } else {
473	CODADEBUG(CODA_VGET,
474		 myprintf(("vget: %s type %d result %d\n",
475			coda_f2s(&VFid), vtype, error)); )
476	cp = make_coda_node(&VFid, vfsp, vtype);
477	*vpp = CTOV(cp);
478    }
479    return(error);
480}
481
482/*
483 * To allow for greater ease of use, some vnodes may be orphaned when
484 * Venus dies.  Certain operations should still be allowed to go
485 * through, but without propagating ophan-ness.  So this function will
486 * get a new vnode for the file from the current run of Venus.  */
487
488int
489getNewVnode(vpp)
490     struct vnode **vpp;
491{
492    struct cfid cfid;
493    struct coda_mntinfo *mi = vftomi((*vpp)->v_mount);
494
495    ENTRY;
496
497    cfid.cfid_len = (short)sizeof(CodaFid);
498    cfid.cfid_fid = VTOC(*vpp)->c_fid;	/* Structure assignment. */
499    /* XXX ? */
500
501    /* We're guessing that if set, the 1st element on the list is a
502     * valid vnode to use. If not, return ENODEV as venus is dead.
503     */
504    if (mi->mi_vfsp == NULL)
505	return ENODEV;
506
507    return coda_fhtovp(mi->mi_vfsp, (struct fid*)&cfid, NULL, vpp,
508		      NULL, NULL);
509}
510
511#include <ufs/ufs/extattr.h>
512#include <ufs/ufs/quota.h>
513#include <ufs/ufs/ufsmount.h>
514/* get the mount structure corresponding to a given device.  Assume
515 * device corresponds to a UFS. Return NULL if no device is found.
516 */
517struct mount *devtomp(dev)
518    struct cdev *dev;
519{
520    struct mount *mp;
521
522    TAILQ_FOREACH(mp, &mountlist, mnt_list) {
523	if (((VFSTOUFS(mp))->um_dev == dev)) {
524	    /* mount corresponds to UFS and the device matches one we want */
525	    return(mp);
526	}
527    }
528    /* mount structure wasn't found */
529    return(NULL);
530}
531
532struct vfsops coda_vfsops = {
533    .vfs_mount =		coda_mount,
534    .vfs_root = 		coda_root,
535    .vfs_start =		coda_start,
536    .vfs_statfs =		coda_nb_statfs,
537    .vfs_sync = 		coda_sync,
538    .vfs_unmount =		coda_unmount,
539};
540
541VFS_SET(coda_vfsops, coda, VFCF_NETWORK);
542