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 /*-
32 * Mach Operating System
33 * Copyright (c) 1989 Carnegie-Mellon University
34 * All rights reserved. The CMU software License Agreement specifies
35 * the terms and conditions for use and redistribution.
36 */
37
38 /*
39 * This code was written for the Coda filesystem at Carnegie Mellon
40 * University. Contributers include David Steere, James Kistler, and
41 * M. Satyanarayanan.
42 */
43
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD: releng/8.4/sys/fs/coda/coda_vfsops.c 208702 2010-06-01 14:29:26Z rwatson $");
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/conf.h>
50 #include <sys/fcntl.h>
51 #include <sys/kernel.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/mount.h>
55 #include <sys/namei.h>
56 #include <sys/proc.h>
57
58 #include <fs/coda/coda.h>
59 #include <fs/coda/cnode.h>
60 #include <fs/coda/coda_vfsops.h>
61 #include <fs/coda/coda_venus.h>
62 #include <fs/coda/coda_subr.h>
63 #include <fs/coda/coda_opstats.h>
64
65 MALLOC_DEFINE(M_CODA, "coda", "Various Coda Structures");
66
67 int codadebug = 0;
68 int coda_vfsop_print_entry = 0;
69 #define ENTRY do { \
70 if (coda_vfsop_print_entry) \
71 myprintf(("Entered %s\n", __func__)); \
72 } while (0)
73
74 struct vnode *coda_ctlvp;
75
76 /*
77 * Structure to keep statistics of internally generated/satisfied calls.
78 */
79 static struct coda_op_stats coda_vfsopstats[CODA_VFSOPS_SIZE];
80
81 #define MARK_ENTRY(op) (coda_vfsopstats[op].entries++)
82 #define MARK_INT_SAT(op) (coda_vfsopstats[op].sat_intrn++)
83 #define MARK_INT_FAIL(op) (coda_vfsopstats[op].unsat_intrn++)
84 #define MARK_INT_GEN(op) (coda_vfsopstats[op].gen_intrn++)
85
86 int
87 coda_vfsopstats_init(void)
88 {
89 int i;
90
91 for (i=0; i<CODA_VFSOPS_SIZE;i++) {
92 coda_vfsopstats[i].opcode = i;
93 coda_vfsopstats[i].entries = 0;
94 coda_vfsopstats[i].sat_intrn = 0;
95 coda_vfsopstats[i].unsat_intrn = 0;
96 coda_vfsopstats[i].gen_intrn = 0;
97 }
98 return (0);
99 }
100
101 static const char *coda_opts[] = { "from", NULL };
102 /*
103 * cfs mount vfsop
104 *
105 * Set up mount info record and attach it to vfs struct.
106 */
107 /*ARGSUSED*/
108 int
109 coda_mount(struct mount *vfsp)
110 {
111 struct vnode *dvp;
112 struct cnode *cp;
113 struct cdev *dev;
114 struct coda_mntinfo *mi;
115 struct vnode *rootvp;
116 struct CodaFid rootfid = INVAL_FID;
117 struct CodaFid ctlfid = CTL_FID;
118 int error;
119 struct nameidata ndp;
120 ENTRY;
121 char *from;
122
123 if (vfs_filteropt(vfsp->mnt_optnew, coda_opts))
124 return (EINVAL);
125 from = vfs_getopts(vfsp->mnt_optnew, "from", &error);
126 if (error)
127 return (error);
128 coda_vfsopstats_init();
129 coda_vnodeopstats_init();
130 MARK_ENTRY(CODA_MOUNT_STATS);
131 if (CODA_MOUNTED(vfsp)) {
132 MARK_INT_FAIL(CODA_MOUNT_STATS);
133 return (EBUSY);
134 }
135
136 /*
137 * Validate mount device. Similar to getmdev().
138 */
139 NDINIT(&ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, from, curthread);
140 error = namei(&ndp);
141 dvp = ndp.ni_vp;
142 if (error) {
143 MARK_INT_FAIL(CODA_MOUNT_STATS);
144 return (error);
145 }
146 if (dvp->v_type != VCHR) {
147 MARK_INT_FAIL(CODA_MOUNT_STATS);
148 vrele(dvp);
149 NDFREE(&ndp, NDF_ONLY_PNBUF);
150 return (ENXIO);
151 }
152 dev = dvp->v_rdev;
153 vrele(dvp);
154 NDFREE(&ndp, NDF_ONLY_PNBUF);
155
156 /*
157 * Initialize the mount record and link it to the vfs struct.
158 */
159 mi = dev2coda_mntinfo(dev);
160 if (!mi) {
161 MARK_INT_FAIL(CODA_MOUNT_STATS);
162 printf("Coda mount: %s is not a cfs device\n", from);
163 return (ENXIO);
164 }
165 if (!VC_OPEN(&mi->mi_vcomm)) {
166 MARK_INT_FAIL(CODA_MOUNT_STATS);
167 return (ENODEV);
168 }
169
170 /*
171 * No initialization (here) of mi_vcomm!
172 */
173 vfsp->mnt_data = mi;
174 vfs_getnewfsid (vfsp);
175 mi->mi_vfsp = vfsp;
176 mi->mi_started = 0; /* XXX See coda_root() */
177
178 /*
179 * Make a root vnode to placate the Vnode interface, but don't
180 * actually make the CODA_ROOT call to venus until the first call to
181 * coda_root in case a server is down while venus is starting.
182 */
183 cp = make_coda_node(&rootfid, vfsp, VDIR);
184 rootvp = CTOV(cp);
185 rootvp->v_vflag |= VV_ROOT;
186 cp = make_coda_node(&ctlfid, vfsp, VREG);
187 coda_ctlvp = CTOV(cp);
188
189 /*
190 * Add vfs and rootvp to chain of vfs hanging off mntinfo.
191 */
192 mi->mi_vfsp = vfsp;
193 mi->mi_rootvp = rootvp;
194 vfs_mountedfrom(vfsp, from);
195
196 /*
197 * Error is currently guaranteed to be zero, but in case some code
198 * changes...
199 */
200 CODADEBUG(1, myprintf(("coda_mount returned %d\n", error)););
201 if (error)
202 MARK_INT_FAIL(CODA_MOUNT_STATS);
203 else
204 MARK_INT_SAT(CODA_MOUNT_STATS);
205 return (error);
206 }
207
208 int
209 coda_unmount(struct mount *vfsp, int mntflags)
210 {
211 struct coda_mntinfo *mi = vftomi(vfsp);
212 int active, error = 0;
213
214 ENTRY;
215 MARK_ENTRY(CODA_UMOUNT_STATS);
216 if (!CODA_MOUNTED(vfsp)) {
217 MARK_INT_FAIL(CODA_UMOUNT_STATS);
218 return (EINVAL);
219 }
220 if (mi->mi_vfsp == vfsp) {
221 /*
222 * We found the victim.
223 */
224 if (!IS_UNMOUNTING(VTOC(mi->mi_rootvp)))
225 return (EBUSY); /* Venus is still running */
226 #ifdef DEBUG
227 printf("coda_unmount: ROOT: vp %p, cp %p\n", mi->mi_rootvp,
228 VTOC(mi->mi_rootvp));
229 #endif
230 vrele(mi->mi_rootvp);
231 mi->mi_rootvp = NULL;
232 vrele(coda_ctlvp);
233 coda_ctlvp = NULL;
234 active = coda_kill(vfsp, NOT_DOWNCALL);
235 error = vflush(mi->mi_vfsp, 0, FORCECLOSE, curthread);
236 #ifdef CODA_VERBOSE
237 printf("coda_unmount: active = %d, vflush active %d\n",
238 active, error);
239 #endif
240 error = 0;
241 /*
242 * I'm going to take this out to allow lookups to go through.
243 * I'm not sure it's important anyway. -- DCS 2/2/94
244 */
245 /* vfsp->VFS_DATA = NULL; */
246
247 /*
248 * No more vfsp's to hold onto.
249 */
250 mi->mi_vfsp = NULL;
251
252 if (error)
253 MARK_INT_FAIL(CODA_UMOUNT_STATS);
254 else
255 MARK_INT_SAT(CODA_UMOUNT_STATS);
256 return (error);
257 }
258 return (EINVAL);
259 }
260
261 /*
262 * Find root of cfs.
263 */
264 int
265 coda_root(struct mount *vfsp, int flags, struct vnode **vpp)
266 {
267 struct coda_mntinfo *mi = vftomi(vfsp);
268 int error;
269 struct proc *p;
270 struct thread *td;
271 struct CodaFid VFid;
272 static const struct CodaFid invalfid = INVAL_FID;
273
274 td = curthread;
275 p = td->td_proc;
276 ENTRY;
277 MARK_ENTRY(CODA_ROOT_STATS);
278 if (vfsp == mi->mi_vfsp) {
279 /*
280 * Cache the root across calls. We only need to pass the
281 * request on to Venus if the root vnode is the dummy we
282 * installed in coda_mount() with all c_fid members zeroed.
283 *
284 * XXX In addition, we assume that the first call to
285 * coda_root() is from vfs_mount() (before the call to
286 * checkdirs()) and return the dummy root node to avoid a
287 * deadlock. This bug is fixed in the Coda CVS repository
288 * but not in any released versions as of 6 Mar 2003.
289 */
290 if (memcmp(&VTOC(mi->mi_rootvp)->c_fid, &invalfid,
291 sizeof(struct CodaFid)) != 0 || mi->mi_started == 0) {
292 /*
293 * Found valid root.
294 */
295 *vpp = mi->mi_rootvp;
296 mi->mi_started = 1;
297
298 /*
299 * On Mach, this is vref. On FreeBSD, vref +
300 * vn_lock.
301 */
302 vref(*vpp);
303 vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY);
304 MARK_INT_SAT(CODA_ROOT_STATS);
305 return (0);
306 }
307 }
308
309 error = venus_root(vftomi(vfsp), td->td_ucred, p, &VFid);
310 if (!error) {
311 /*
312 * Save the new rootfid in the cnode, and rehash the cnode
313 * into the 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 *vpp = mi->mi_rootvp;
319 vref(*vpp);
320 vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY);
321 MARK_INT_SAT(CODA_ROOT_STATS);
322 } else if (error == ENODEV || error == EINTR) {
323 /*
324 * Gross hack here!
325 *
326 * If Venus fails to respond to the CODA_ROOT call, coda_call
327 * returns ENODEV. Return the uninitialized root vnode to
328 * allow vfs operations such as unmount to continue. Without
329 * this hack, there is no way to do an unmount if Venus dies
330 * before a successful CODA_ROOT call is done. All vnode
331 * operations will fail.
332 */
333 *vpp = mi->mi_rootvp;
334 vref(*vpp);
335 vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY);
336 MARK_INT_FAIL(CODA_ROOT_STATS);
337 error = 0;
338 } else {
339 CODADEBUG(CODA_ROOT, myprintf(("error %d in CODA_ROOT\n",
340 error)););
341 MARK_INT_FAIL(CODA_ROOT_STATS);
342 }
343 return (error);
344 }
345
346 /*
347 * Get filesystem statistics.
348 */
349 int
350 coda_statfs(struct mount *vfsp, struct statfs *sbp)
351 {
352
353 ENTRY;
354 MARK_ENTRY(CODA_STATFS_STATS);
355 if (!CODA_MOUNTED(vfsp)) {
356 MARK_INT_FAIL(CODA_STATFS_STATS);
357 return (EINVAL);
358 }
359
360 /*
361 * XXX - what to do about f_flags, others? --bnoble
362 *
363 * We just make up free space counts that are sufficiently large.
364 */
365 sbp->f_flags = 0;
366 sbp->f_bsize = 8192; /* XXX */
367 sbp->f_iosize = 8192; /* XXX */
368 #define CODA_SFS_SIZ 0x8AB75D
369 sbp->f_blocks = CODA_SFS_SIZ;
370 sbp->f_bfree = CODA_SFS_SIZ;
371 sbp->f_bavail = CODA_SFS_SIZ;
372 sbp->f_files = CODA_SFS_SIZ;
373 sbp->f_ffree = CODA_SFS_SIZ;
374 MARK_INT_SAT(CODA_STATFS_STATS);
375 return (0);
376 }
377
378 /*
379 * Flush any pending I/O.
380 */
381 int
382 coda_sync(struct mount *vfsp, int waitfor)
383 {
384
385 ENTRY;
386 MARK_ENTRY(CODA_SYNC_STATS);
387 MARK_INT_SAT(CODA_SYNC_STATS);
388 return (0);
389 }
390
391 /*
392 * fhtovp is now what vget used to be in 4.3-derived systems. For some silly
393 * reason, vget is now keyed by a 32 bit ino_t, rather than a type-specific
394 * fid.
395 *
396 * XXX: coda_fhtovp is currently not hooked up, so no NFS export for Coda.
397 * We leave it here in the hopes that someone will find it someday and hook
398 * it up. Among other things, it will need some reworking to match the
399 * vfs_fhtovp_t prototype.
400 */
401 int
402 coda_fhtovp(struct mount *vfsp, struct fid *fhp, struct mbuf *nam,
403 struct vnode **vpp, int *exflagsp, struct ucred **creadanonp)
404 {
405 struct cfid *cfid = (struct cfid *)fhp;
406 struct cnode *cp = NULL;
407 int error;
408 struct thread *td = curthread; /* XXX -mach */
409 struct proc *p = td->td_proc;
410 struct CodaFid VFid;
411 int vtype;
412
413 ENTRY;
414 MARK_ENTRY(CODA_VGET_STATS);
415
416 /*
417 * Check for vget of control object.
418 */
419 if (IS_CTL_FID(&cfid->cfid_fid)) {
420 *vpp = coda_ctlvp;
421 vref(coda_ctlvp);
422 MARK_INT_SAT(CODA_VGET_STATS);
423 return (0);
424 }
425 error = venus_fhtovp(vftomi(vfsp), &cfid->cfid_fid, td->td_ucred, p,
426 &VFid, &vtype);
427 if (error) {
428 CODADEBUG(CODA_VGET, myprintf(("vget error %d\n",error)););
429 *vpp = NULL;
430 } else {
431 CODADEBUG(CODA_VGET, myprintf(("vget: %s type %d result "
432 "%d\n", coda_f2s(&VFid), vtype, error)););
433 cp = make_coda_node(&VFid, vfsp, vtype);
434 *vpp = CTOV(cp);
435 }
436 return (error);
437 }
438
439 struct vfsops coda_vfsops = {
440 .vfs_mount = coda_mount,
441 .vfs_root = coda_root,
442 .vfs_statfs = coda_statfs,
443 .vfs_sync = coda_sync,
444 .vfs_unmount = coda_unmount,
445 };
446 VFS_SET(coda_vfsops, coda, VFCF_NETWORK);
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