coda_vfsops.c revision 171379 
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 171379 2007-07-11 21:34:41Z rwatson $");
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", "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 MARK_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     * Initialize the mount record and link it to the vfs struct
157     */
158    mi = dev2coda_mntinfo(dev);
159    if (!mi) {
160	MARK_INT_FAIL(CODA_MOUNT_STATS);
161	printf("Coda mount: %s is not a cfs device\n", from);
162	return(ENXIO);
163    }
164
165    if (!VC_OPEN(&mi->mi_vcomm)) {
166	MARK_INT_FAIL(CODA_MOUNT_STATS);
167	return(ENODEV);
168    }
169
170    /* No initialization (here) of mi_vcomm! */
171    vfsp->mnt_data = (qaddr_t)mi;
172    vfs_getnewfsid (vfsp);
173
174    mi->mi_vfsp = vfsp;
175    mi->mi_started = 0;			/* XXX See coda_root() */
176
177    /*
178     * Make a root vnode to placate the Vnode interface, but don't
179     * actually make the CODA_ROOT call to venus until the first call
180     * to coda_root in case a server is down while venus is starting.
181     */
182    cp = make_coda_node(&rootfid, vfsp, VDIR);
183    rootvp = CTOV(cp);
184    rootvp->v_vflag |= VV_ROOT;
185
186    cp = make_coda_node(&ctlfid, vfsp, VREG);
187    coda_ctlvp = CTOV(cp);
188
189    /* Add vfs and rootvp to chain of vfs hanging off mntinfo */
190    mi->mi_vfsp = vfsp;
191    mi->mi_rootvp = rootvp;
192
193    vfs_mountedfrom(vfsp, from);
194    /* error is currently guaranteed to be zero, but in case some
195       code changes... */
196    CODADEBUG(1,
197	     myprintf(("coda_omount returned %d\n",error)););
198    if (error)
199	MARK_INT_FAIL(CODA_MOUNT_STATS);
200    else
201	MARK_INT_SAT(CODA_MOUNT_STATS);
202
203    return(error);
204}
205
206int
207coda_unmount(vfsp, mntflags, td)
208    struct mount *vfsp;
209    int mntflags;
210    struct thread *td;
211{
212    struct coda_mntinfo *mi = vftomi(vfsp);
213    int active, error = 0;
214
215    ENTRY;
216    MARK_ENTRY(CODA_UMOUNT_STATS);
217    if (!CODA_MOUNTED(vfsp)) {
218	MARK_INT_FAIL(CODA_UMOUNT_STATS);
219	return(EINVAL);
220    }
221
222    if (mi->mi_vfsp == vfsp) {	/* We found the victim */
223	if (!IS_UNMOUNTING(VTOC(mi->mi_rootvp)))
224	    return (EBUSY); 	/* Venus is still running */
225
226#ifdef	DEBUG
227	printf("coda_unmount: ROOT: vp %p, cp %p\n", mi->mi_rootvp, VTOC(mi->mi_rootvp));
228#endif
229	vrele(mi->mi_rootvp);
230	active = coda_kill(vfsp, NOT_DOWNCALL);
231	ASSERT_VOP_LOCKED(mi->mi_rootvp, "coda_unmount");
232	mi->mi_rootvp->v_vflag &= ~VV_ROOT;
233	error = vflush(mi->mi_vfsp, 0, FORCECLOSE, td);
234#ifdef CODA_VERBOSE
235	printf("coda_unmount: active = %d, vflush active %d\n", active, error);
236#endif
237	error = 0;
238	/* I'm going to take this out to allow lookups to go through. I'm
239	 * not sure it's important anyway. -- DCS 2/2/94
240	 */
241	/* vfsp->VFS_DATA = NULL; */
242
243	/* No more vfsp's to hold onto */
244	mi->mi_vfsp = NULL;
245	mi->mi_rootvp = NULL;
246
247	if (error)
248	    MARK_INT_FAIL(CODA_UMOUNT_STATS);
249	else
250	    MARK_INT_SAT(CODA_UMOUNT_STATS);
251
252	return(error);
253    }
254    return (EINVAL);
255}
256
257/*
258 * find root of cfs
259 */
260int
261coda_root(vfsp, flags, vpp, td)
262	struct mount *vfsp;
263	int flags;
264	struct vnode **vpp;
265	struct thread *td;
266{
267    struct coda_mntinfo *mi = vftomi(vfsp);
268    struct vnode **result;
269    int error;
270    struct proc *p = td->td_proc;
271    CodaFid VFid;
272    static const CodaFid invalfid = INVAL_FID;
273
274    ENTRY;
275    MARK_ENTRY(CODA_ROOT_STATS);
276    result = NULL;
277
278    if (vfsp == mi->mi_vfsp) {
279	/*
280	 * Cache the root across calls. We only need to pass the request
281	 * on to Venus if the root vnode is the dummy we installed in
282	 * coda_omount() with all c_fid members zeroed.
283	 *
284	 * XXX In addition, we assume that the first call to coda_root()
285	 * is from vfs_omount()
286	 * (before the call to checkdirs()) and return the dummy root
287	 * node to avoid a deadlock. This bug is fixed in the Coda CVS
288	 * repository but not in any released versions as of 6 Mar 2003.
289	 */
290	if (memcmp(&VTOC(mi->mi_rootvp)->c_fid, &invalfid,
291	    sizeof(CodaFid)) != 0 || mi->mi_started == 0)
292	    { /* Found valid root. */
293		*vpp = mi->mi_rootvp;
294		mi->mi_started = 1;
295
296		/* On Mach, this is vref.  On NetBSD, VOP_LOCK */
297#if	1
298		vref(*vpp);
299		vn_lock(*vpp, LK_EXCLUSIVE, td);
300#else
301		vget(*vpp, LK_EXCLUSIVE, td);
302#endif
303		MARK_INT_SAT(CODA_ROOT_STATS);
304		return(0);
305	    }
306    }
307
308    error = venus_root(vftomi(vfsp), td->td_ucred, p, &VFid);
309
310    if (!error) {
311	/*
312	 * Save the new rootfid in the cnode, and rehash the cnode into the
313	 * cnode hash with the new fid key.
314	 */
315	coda_unsave(VTOC(mi->mi_rootvp));
316	VTOC(mi->mi_rootvp)->c_fid = VFid;
317	coda_save(VTOC(mi->mi_rootvp));
318
319	*vpp = mi->mi_rootvp;
320#if	1
321	vref(*vpp);
322	vn_lock(*vpp, LK_EXCLUSIVE, td);
323#else
324	vget(*vpp, LK_EXCLUSIVE, td);
325#endif
326
327	MARK_INT_SAT(CODA_ROOT_STATS);
328	goto exit;
329    } else if (error == ENODEV || error == EINTR) {
330	/* Gross hack here! */
331	/*
332	 * If Venus fails to respond to the CODA_ROOT call, coda_call returns
333	 * ENODEV. Return the uninitialized root vnode to allow vfs
334	 * operations such as unmount to continue. Without this hack,
335	 * there is no way to do an unmount if Venus dies before a
336	 * successful CODA_ROOT call is done. All vnode operations
337	 * will fail.
338	 */
339	*vpp = mi->mi_rootvp;
340#if	1
341	vref(*vpp);
342	vn_lock(*vpp, LK_EXCLUSIVE, td);
343#else
344	vget(*vpp, LK_EXCLUSIVE, td);
345#endif
346
347	MARK_INT_FAIL(CODA_ROOT_STATS);
348	error = 0;
349	goto exit;
350    } else {
351	CODADEBUG( CODA_ROOT, myprintf(("error %d in CODA_ROOT\n", error)); );
352	MARK_INT_FAIL(CODA_ROOT_STATS);
353
354	goto exit;
355    }
356
357 exit:
358    return(error);
359}
360
361/*
362 * Get filesystem statistics.
363 */
364int
365coda_nb_statfs(vfsp, sbp, td)
366    register struct mount *vfsp;
367    struct statfs *sbp;
368    struct thread *td;
369{
370    ENTRY;
371/*  MARK_ENTRY(CODA_STATFS_STATS); */
372    if (!CODA_MOUNTED(vfsp)) {
373/*	MARK_INT_FAIL(CODA_STATFS_STATS);*/
374	return(EINVAL);
375    }
376
377    bzero(sbp, sizeof(struct statfs));
378    /* XXX - what to do about f_flags, others? --bnoble */
379    /* Below This is what AFS does
380    	#define NB_SFS_SIZ 0x895440
381     */
382    /* Note: Normal fs's have a bsize of 0x400 == 1024 */
383    sbp->f_type = vfsp->mnt_vfc->vfc_typenum;
384    sbp->f_bsize = 8192; /* XXX */
385    sbp->f_iosize = 8192; /* XXX */
386#define NB_SFS_SIZ 0x8AB75D
387    sbp->f_blocks = NB_SFS_SIZ;
388    sbp->f_bfree = NB_SFS_SIZ;
389    sbp->f_bavail = NB_SFS_SIZ;
390    sbp->f_files = NB_SFS_SIZ;
391    sbp->f_ffree = NB_SFS_SIZ;
392    bcopy((caddr_t)&(vfsp->mnt_stat.f_fsid), (caddr_t)&(sbp->f_fsid), sizeof (fsid_t));
393    snprintf(sbp->f_mntonname, sizeof(sbp->f_mntonname), "/coda");
394    snprintf(sbp->f_fstypename, sizeof(sbp->f_fstypename), "coda");
395/*  MARK_INT_SAT(CODA_STATFS_STATS); */
396    return(0);
397}
398
399/*
400 * Flush any pending I/O.
401 */
402int
403coda_sync(vfsp, waitfor, td)
404    struct mount *vfsp;
405    int    waitfor;
406    struct thread *td;
407{
408    ENTRY;
409    MARK_ENTRY(CODA_SYNC_STATS);
410    MARK_INT_SAT(CODA_SYNC_STATS);
411    return(0);
412}
413
414/*
415 * fhtovp is now what vget used to be in 4.3-derived systems.  For
416 * some silly reason, vget is now keyed by a 32 bit ino_t, rather than
417 * a type-specific fid.
418 */
419int
420coda_fhtovp(vfsp, fhp, nam, vpp, exflagsp, creadanonp)
421    register struct mount *vfsp;
422    struct fid *fhp;
423    struct mbuf *nam;
424    struct vnode **vpp;
425    int *exflagsp;
426    struct ucred **creadanonp;
427{
428    struct cfid *cfid = (struct cfid *)fhp;
429    struct cnode *cp = 0;
430    int error;
431    struct thread *td = curthread; /* XXX -mach */
432    struct proc *p = td->td_proc;
433    CodaFid VFid;
434    int vtype;
435
436    ENTRY;
437
438    MARK_ENTRY(CODA_VGET_STATS);
439    /* Check for vget of control object. */
440    if (IS_CTL_FID(&cfid->cfid_fid)) {
441	*vpp = coda_ctlvp;
442	vref(coda_ctlvp);
443	MARK_INT_SAT(CODA_VGET_STATS);
444	return(0);
445    }
446
447    error = venus_fhtovp(vftomi(vfsp), &cfid->cfid_fid, td->td_ucred, p, &VFid, &vtype);
448
449    if (error) {
450	CODADEBUG(CODA_VGET, myprintf(("vget error %d\n",error));)
451	    *vpp = (struct vnode *)0;
452    } else {
453	CODADEBUG(CODA_VGET,
454		 myprintf(("vget: %s type %d result %d\n",
455			coda_f2s(&VFid), vtype, error)); )
456	cp = make_coda_node(&VFid, vfsp, vtype);
457	*vpp = CTOV(cp);
458    }
459    return(error);
460}
461
462/*
463 * To allow for greater ease of use, some vnodes may be orphaned when
464 * Venus dies.  Certain operations should still be allowed to go
465 * through, but without propagating ophan-ness.  So this function will
466 * get a new vnode for the file from the current run of Venus.  */
467
468int
469getNewVnode(vpp)
470     struct vnode **vpp;
471{
472    struct cfid cfid;
473    struct coda_mntinfo *mi = vftomi((*vpp)->v_mount);
474
475    ENTRY;
476
477    cfid.cfid_len = (short)sizeof(CodaFid);
478    cfid.cfid_fid = VTOC(*vpp)->c_fid;	/* Structure assignment. */
479    /* XXX ? */
480
481    /* We're guessing that if set, the 1st element on the list is a
482     * valid vnode to use. If not, return ENODEV as venus is dead.
483     */
484    if (mi->mi_vfsp == NULL)
485	return ENODEV;
486
487    return coda_fhtovp(mi->mi_vfsp, (struct fid*)&cfid, NULL, vpp,
488		      NULL, NULL);
489}
490
491#include <ufs/ufs/extattr.h>
492#include <ufs/ufs/quota.h>
493#include <ufs/ufs/ufsmount.h>
494/* get the mount structure corresponding to a given device.  Assume
495 * device corresponds to a UFS. Return NULL if no device is found.
496 */
497struct mount *devtomp(dev)
498    struct cdev *dev;
499{
500    struct mount *mp;
501
502    TAILQ_FOREACH(mp, &mountlist, mnt_list) {
503	if (((VFSTOUFS(mp))->um_dev == dev)) {
504	    /* mount corresponds to UFS and the device matches one we want */
505	    return(mp);
506	}
507    }
508    /* mount structure wasn't found */
509    return(NULL);
510}
511
512struct vfsops coda_vfsops = {
513    .vfs_mount =		coda_mount,
514    .vfs_root = 		coda_root,
515    .vfs_statfs =		coda_nb_statfs,
516    .vfs_sync = 		coda_sync,
517    .vfs_unmount =		coda_unmount,
518};
519
520VFS_SET(coda_vfsops, coda, VFCF_NETWORK);
521