nfs_iod.c revision 1.1 1 /* $NetBSD: nfs_iod.c,v 1.1 2008/11/19 18:36:09 ad Exp $ */
2
3 /*
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Rick Macklem at The University of Guelph.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)nfs_syscalls.c 8.5 (Berkeley) 3/30/95
35 */
36
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: nfs_iod.c,v 1.1 2008/11/19 18:36:09 ad Exp $");
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/file.h>
44 #include <sys/stat.h>
45 #include <sys/vnode.h>
46 #include <sys/mount.h>
47 #include <sys/proc.h>
48 #include <sys/uio.h>
49 #include <sys/malloc.h>
50 #include <sys/kmem.h>
51 #include <sys/buf.h>
52 #include <sys/mbuf.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 #include <sys/signalvar.h>
56 #include <sys/domain.h>
57 #include <sys/protosw.h>
58 #include <sys/namei.h>
59 #include <sys/syslog.h>
60 #include <sys/filedesc.h>
61 #include <sys/kthread.h>
62 #include <sys/kauth.h>
63 #include <sys/syscallargs.h>
64
65 #include <netinet/in.h>
66 #include <netinet/tcp.h>
67 #include <nfs/xdr_subs.h>
68 #include <nfs/rpcv2.h>
69 #include <nfs/nfsproto.h>
70 #include <nfs/nfs.h>
71 #include <nfs/nfsm_subs.h>
72 #include <nfs/nfsrvcache.h>
73 #include <nfs/nfsmount.h>
74 #include <nfs/nfsnode.h>
75 #include <nfs/nfsrtt.h>
76 #include <nfs/nfs_var.h>
77
78 int nuidhash_max = NFS_MAXUIDHASH;
79
80 /*
81 * locking order:
82 * nfs_iodlist_lock -> nid_lock -> nm_lock
83 */
84 kmutex_t nfs_iodlist_lock;
85 struct nfs_iodlist nfs_iodlist_idle;
86 struct nfs_iodlist nfs_iodlist_all;
87 int nfs_niothreads = -1; /* == "0, and has never been set" */
88 int nfs_defect = 0;
89
90 /*
91 * Asynchronous I/O threads for client nfs.
92 * They do read-ahead and write-behind operations on the block I/O cache.
93 * Never returns unless it fails or gets killed.
94 */
95
96 static void
97 nfssvc_iod(void *arg)
98 {
99 struct buf *bp;
100 struct nfs_iod *myiod;
101 struct nfsmount *nmp;
102
103 myiod = kmem_alloc(sizeof(*myiod), KM_SLEEP);
104 mutex_init(&myiod->nid_lock, MUTEX_DEFAULT, IPL_NONE);
105 cv_init(&myiod->nid_cv, "nfsiod");
106 myiod->nid_exiting = false;
107 myiod->nid_mount = NULL;
108 mutex_enter(&nfs_iodlist_lock);
109 LIST_INSERT_HEAD(&nfs_iodlist_all, myiod, nid_all);
110 mutex_exit(&nfs_iodlist_lock);
111
112 for (;;) {
113 mutex_enter(&nfs_iodlist_lock);
114 LIST_INSERT_HEAD(&nfs_iodlist_idle, myiod, nid_idle);
115 mutex_exit(&nfs_iodlist_lock);
116
117 mutex_enter(&myiod->nid_lock);
118 while (/*CONSTCOND*/ true) {
119 nmp = myiod->nid_mount;
120 if (nmp) {
121 myiod->nid_mount = NULL;
122 break;
123 }
124 if (__predict_false(myiod->nid_exiting)) {
125 /*
126 * drop nid_lock to preserve locking order.
127 */
128 mutex_exit(&myiod->nid_lock);
129 mutex_enter(&nfs_iodlist_lock);
130 mutex_enter(&myiod->nid_lock);
131 /*
132 * recheck nid_mount because nfs_asyncio can
133 * pick us in the meantime as we are still on
134 * nfs_iodlist_lock.
135 */
136 if (myiod->nid_mount != NULL) {
137 mutex_exit(&nfs_iodlist_lock);
138 continue;
139 }
140 LIST_REMOVE(myiod, nid_idle);
141 mutex_exit(&nfs_iodlist_lock);
142 goto quit;
143 }
144 cv_wait(&myiod->nid_cv, &myiod->nid_lock);
145 }
146 mutex_exit(&myiod->nid_lock);
147
148 mutex_enter(&nmp->nm_lock);
149 while ((bp = TAILQ_FIRST(&nmp->nm_bufq)) != NULL) {
150 /* Take one off the front of the list */
151 TAILQ_REMOVE(&nmp->nm_bufq, bp, b_freelist);
152 nmp->nm_bufqlen--;
153 if (nmp->nm_bufqlen < 2 * nmp->nm_bufqiods) {
154 cv_broadcast(&nmp->nm_aiocv);
155 }
156 mutex_exit(&nmp->nm_lock);
157 KERNEL_LOCK(1, curlwp);
158 (void)nfs_doio(bp);
159 KERNEL_UNLOCK_LAST(curlwp);
160 mutex_enter(&nmp->nm_lock);
161 /*
162 * If there are more than one iod on this mount,
163 * then defect so that the iods can be shared out
164 * fairly between the mounts
165 */
166 if (nfs_defect && nmp->nm_bufqiods > 1) {
167 break;
168 }
169 }
170 KASSERT(nmp->nm_bufqiods > 0);
171 nmp->nm_bufqiods--;
172 mutex_exit(&nmp->nm_lock);
173 }
174 quit:
175 KASSERT(myiod->nid_mount == NULL);
176 mutex_exit(&myiod->nid_lock);
177
178 cv_destroy(&myiod->nid_cv);
179 mutex_destroy(&myiod->nid_lock);
180 kmem_free(myiod, sizeof(*myiod));
181
182 kthread_exit(0);
183 }
184
185 void
186 nfs_iodinit(void)
187 {
188
189 mutex_init(&nfs_iodlist_lock, MUTEX_DEFAULT, IPL_NONE);
190 LIST_INIT(&nfs_iodlist_all);
191 LIST_INIT(&nfs_iodlist_idle);
192 }
193
194 void
195 nfs_iodfini(void)
196 {
197 int error;
198
199 error = nfs_set_niothreads(0);
200 KASSERT(error == 0);
201 mutex_destroy(&nfs_iodlist_lock);
202 }
203
204 int
205 nfs_set_niothreads(int newval)
206 {
207 struct nfs_iod *nid;
208 int error = 0;
209 int hold_count;
210
211 KERNEL_UNLOCK_ALL(curlwp, &hold_count);
212
213 mutex_enter(&nfs_iodlist_lock);
214 /* clamp to sane range */
215 nfs_niothreads = max(0, min(newval, NFS_MAXASYNCDAEMON));
216
217 while (nfs_numasync != nfs_niothreads && error == 0) {
218 while (nfs_numasync < nfs_niothreads) {
219
220 /*
221 * kthread_create can wait for pagedaemon and
222 * pagedaemon can wait for nfsiod which needs to acquire
223 * nfs_iodlist_lock.
224 */
225
226 mutex_exit(&nfs_iodlist_lock);
227 error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
228 nfssvc_iod, NULL, NULL, "nfsio");
229 mutex_enter(&nfs_iodlist_lock);
230 if (error) {
231 /* give up */
232 nfs_niothreads = nfs_numasync;
233 break;
234 }
235 nfs_numasync++;
236 }
237 while (nfs_numasync > nfs_niothreads) {
238 nid = LIST_FIRST(&nfs_iodlist_all);
239 if (nid == NULL) {
240 /* iod has not started yet. */
241 kpause("nfsiorm", false, hz, &nfs_iodlist_lock);
242 continue;
243 }
244 LIST_REMOVE(nid, nid_all);
245 mutex_enter(&nid->nid_lock);
246 KASSERT(!nid->nid_exiting);
247 nid->nid_exiting = true;
248 cv_signal(&nid->nid_cv);
249 mutex_exit(&nid->nid_lock);
250 nfs_numasync--;
251 }
252 }
253 mutex_exit(&nfs_iodlist_lock);
254
255 KERNEL_LOCK(hold_count, curlwp);
256 return error;
257 }
258
259 /*
260 * Get an authorization string for the uid by having the mount_nfs sitting
261 * on this mount point porpous out of the kernel and do it.
262 */
263 int
264 nfs_getauth(nmp, rep, cred, auth_str, auth_len, verf_str, verf_len, key)
265 struct nfsmount *nmp;
266 struct nfsreq *rep;
267 kauth_cred_t cred;
268 char **auth_str;
269 int *auth_len;
270 char *verf_str;
271 int *verf_len;
272 NFSKERBKEY_T key; /* return session key */
273 {
274 int error = 0;
275
276 while ((nmp->nm_iflag & NFSMNT_WAITAUTH) == 0) {
277 nmp->nm_iflag |= NFSMNT_WANTAUTH;
278 (void) tsleep((void *)&nmp->nm_authtype, PSOCK,
279 "nfsauth1", 2 * hz);
280 error = nfs_sigintr(nmp, rep, rep->r_lwp);
281 if (error) {
282 nmp->nm_iflag &= ~NFSMNT_WANTAUTH;
283 return (error);
284 }
285 }
286 nmp->nm_iflag &= ~(NFSMNT_WAITAUTH | NFSMNT_WANTAUTH);
287 nmp->nm_authstr = *auth_str = (char *)malloc(RPCAUTH_MAXSIZ, M_TEMP, M_WAITOK);
288 nmp->nm_authlen = RPCAUTH_MAXSIZ;
289 nmp->nm_verfstr = verf_str;
290 nmp->nm_verflen = *verf_len;
291 nmp->nm_authuid = kauth_cred_geteuid(cred);
292 wakeup((void *)&nmp->nm_authstr);
293
294 /*
295 * And wait for mount_nfs to do its stuff.
296 */
297 while ((nmp->nm_iflag & NFSMNT_HASAUTH) == 0 && error == 0) {
298 (void) tsleep((void *)&nmp->nm_authlen, PSOCK,
299 "nfsauth2", 2 * hz);
300 error = nfs_sigintr(nmp, rep, rep->r_lwp);
301 }
302 if (nmp->nm_iflag & NFSMNT_AUTHERR) {
303 nmp->nm_iflag &= ~NFSMNT_AUTHERR;
304 error = EAUTH;
305 }
306 if (error)
307 free((void *)*auth_str, M_TEMP);
308 else {
309 *auth_len = nmp->nm_authlen;
310 *verf_len = nmp->nm_verflen;
311 memcpy(key, nmp->nm_key, sizeof (NFSKERBKEY_T));
312 }
313 nmp->nm_iflag &= ~NFSMNT_HASAUTH;
314 nmp->nm_iflag |= NFSMNT_WAITAUTH;
315 if (nmp->nm_iflag & NFSMNT_WANTAUTH) {
316 nmp->nm_iflag &= ~NFSMNT_WANTAUTH;
317 wakeup((void *)&nmp->nm_authtype);
318 }
319 return (error);
320 }
321
322 /*
323 * Get a nickname authenticator and verifier.
324 */
325 int
326 nfs_getnickauth(struct nfsmount *nmp, kauth_cred_t cred, char **auth_str,
327 int *auth_len, char *verf_str, int verf_len)
328 {
329 struct timeval ktvin, ktvout, tv;
330 struct nfsuid *nuidp;
331 u_int32_t *nickp, *verfp;
332
333 memset(&ktvout, 0, sizeof ktvout); /* XXX gcc */
334
335 #ifdef DIAGNOSTIC
336 if (verf_len < (4 * NFSX_UNSIGNED))
337 panic("nfs_getnickauth verf too small");
338 #endif
339 LIST_FOREACH(nuidp, NMUIDHASH(nmp, kauth_cred_geteuid(cred)), nu_hash) {
340 if (kauth_cred_geteuid(nuidp->nu_cr) == kauth_cred_geteuid(cred))
341 break;
342 }
343 if (!nuidp || nuidp->nu_expire < time_second)
344 return (EACCES);
345
346 /*
347 * Move to the end of the lru list (end of lru == most recently used).
348 */
349 TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp, nu_lru);
350 TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp, nu_lru);
351
352 nickp = (u_int32_t *)malloc(2 * NFSX_UNSIGNED, M_TEMP, M_WAITOK);
353 *nickp++ = txdr_unsigned(RPCAKN_NICKNAME);
354 *nickp = txdr_unsigned(nuidp->nu_nickname);
355 *auth_str = (char *)nickp;
356 *auth_len = 2 * NFSX_UNSIGNED;
357
358 /*
359 * Now we must encrypt the verifier and package it up.
360 */
361 verfp = (u_int32_t *)verf_str;
362 *verfp++ = txdr_unsigned(RPCAKN_NICKNAME);
363 getmicrotime(&tv);
364 if (tv.tv_sec > nuidp->nu_timestamp.tv_sec ||
365 (tv.tv_sec == nuidp->nu_timestamp.tv_sec &&
366 tv.tv_usec > nuidp->nu_timestamp.tv_usec))
367 nuidp->nu_timestamp = tv;
368 else
369 nuidp->nu_timestamp.tv_usec++;
370 ktvin.tv_sec = txdr_unsigned(nuidp->nu_timestamp.tv_sec);
371 ktvin.tv_usec = txdr_unsigned(nuidp->nu_timestamp.tv_usec);
372
373 /*
374 * Now encrypt the timestamp verifier in ecb mode using the session
375 * key.
376 */
377 #ifdef NFSKERB
378 XXX
379 #endif
380
381 *verfp++ = ktvout.tv_sec;
382 *verfp++ = ktvout.tv_usec;
383 *verfp = 0;
384 return (0);
385 }
386
387 /*
388 * Save the current nickname in a hash list entry on the mount point.
389 */
390 int
391 nfs_savenickauth(nmp, cred, len, key, mdp, dposp, mrep)
392 struct nfsmount *nmp;
393 kauth_cred_t cred;
394 int len;
395 NFSKERBKEY_T key;
396 struct mbuf **mdp;
397 char **dposp;
398 struct mbuf *mrep;
399 {
400 struct nfsuid *nuidp;
401 u_int32_t *tl;
402 int32_t t1;
403 struct mbuf *md = *mdp;
404 struct timeval ktvin, ktvout;
405 u_int32_t nick;
406 char *dpos = *dposp, *cp2;
407 int deltasec, error = 0;
408
409 memset(&ktvout, 0, sizeof ktvout); /* XXX gcc */
410
411 if (len == (3 * NFSX_UNSIGNED)) {
412 nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
413 ktvin.tv_sec = *tl++;
414 ktvin.tv_usec = *tl++;
415 nick = fxdr_unsigned(u_int32_t, *tl);
416
417 /*
418 * Decrypt the timestamp in ecb mode.
419 */
420 #ifdef NFSKERB
421 XXX
422 #endif
423 ktvout.tv_sec = fxdr_unsigned(long, ktvout.tv_sec);
424 ktvout.tv_usec = fxdr_unsigned(long, ktvout.tv_usec);
425 deltasec = time_second - ktvout.tv_sec;
426 if (deltasec < 0)
427 deltasec = -deltasec;
428 /*
429 * If ok, add it to the hash list for the mount point.
430 */
431 if (deltasec <= NFS_KERBCLOCKSKEW) {
432 if (nmp->nm_numuids < nuidhash_max) {
433 nmp->nm_numuids++;
434 nuidp = kmem_alloc(sizeof(*nuidp), KM_SLEEP);
435 } else {
436 nuidp = TAILQ_FIRST(&nmp->nm_uidlruhead);
437 LIST_REMOVE(nuidp, nu_hash);
438 TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp,
439 nu_lru);
440 }
441 nuidp->nu_flag = 0;
442 kauth_cred_seteuid(nuidp->nu_cr, kauth_cred_geteuid(cred));
443 nuidp->nu_expire = time_second + NFS_KERBTTL;
444 nuidp->nu_timestamp = ktvout;
445 nuidp->nu_nickname = nick;
446 memcpy(nuidp->nu_key, key, sizeof (NFSKERBKEY_T));
447 TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp,
448 nu_lru);
449 LIST_INSERT_HEAD(NMUIDHASH(nmp, kauth_cred_geteuid(cred)),
450 nuidp, nu_hash);
451 }
452 } else
453 nfsm_adv(nfsm_rndup(len));
454 nfsmout:
455 *mdp = md;
456 *dposp = dpos;
457 return (error);
458 }
459