xref: /netbsd-src/usr.sbin/puffs/mount_9p/node.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: node.c,v 1.19 2007/11/30 19:02:39 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2007  Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #ifndef lint
30 __RCSID("$NetBSD: node.c,v 1.19 2007/11/30 19:02:39 pooka Exp $");
31 #endif /* !lint */
32 
33 #include <assert.h>
34 #include <errno.h>
35 #include <puffs.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 
39 #include "ninepuffs.h"
40 #include "nineproto.h"
41 
42 static void *
43 nodecmp(struct puffs_usermount *pu, struct puffs_node *pn, void *arg)
44 {
45 	struct vattr *vap = &pn->pn_va;
46 	struct qid9p *qid = arg;
47 
48 	if (vap->va_fileid == qid->qidpath)
49 		return pn;
50 
51 	return NULL;
52 }
53 
54 static int
55 do_getattr(struct puffs_usermount *pu, struct puffs_node *pn, struct vattr *vap)
56 {
57 	AUTOVAR(pu);
58 	struct p9pnode *p9n = pn->pn_data;
59 
60 	p9pbuf_put_1(pb, P9PROTO_T_STAT);
61 	p9pbuf_put_2(pb, tag);
62 	p9pbuf_put_4(pb, p9n->fid_base);
63 	GETRESPONSE(pb);
64 
65 	rv = proto_expect_stat(pb, vap);
66 
67  out:
68 	RETURN(rv);
69 }
70 
71 int
72 puffs9p_node_getattr(struct puffs_usermount *pu, void *opc, struct vattr *vap,
73 	const struct puffs_cred *pcr)
74 {
75 	struct puffs_node *pn = opc;
76 	int rv;
77 
78 	rv = do_getattr(pu, pn, &pn->pn_va);
79 	if (rv == 0)
80 		memcpy(vap, &pn->pn_va, sizeof(struct vattr));
81 	return rv;
82 }
83 
84 int
85 puffs9p_node_lookup(struct puffs_usermount *pu, void *opc, struct puffs_newinfo *pni,
86 	const struct puffs_cn *pcn)
87 {
88 	AUTOVAR(pu);
89 	struct puffs_node *pn, *pn_dir = opc;
90 	struct p9pnode *p9n_dir = pn_dir->pn_data;
91 	p9ptag_t tfid = NEXTFID(p9p);
92 	struct qid9p newqid;
93 	uint16_t nqid;
94 
95 	p9pbuf_put_1(pb, P9PROTO_T_WALK);
96 	p9pbuf_put_2(pb, tag);
97 	p9pbuf_put_4(pb, p9n_dir->fid_base);
98 	p9pbuf_put_4(pb, tfid);
99 	p9pbuf_put_2(pb, 1);
100 	p9pbuf_put_str(pb, pcn->pcn_name);
101 	GETRESPONSE(pb);
102 
103 	rv = proto_expect_walk_nqids(pb, &nqid);
104 	if (rv) {
105 		rv = ENOENT;
106 		goto out;
107 	}
108 	if (nqid != 1) {
109 		rv = EPROTO;
110 		goto out;
111 	}
112 	if ((rv = proto_getqid(pb, &newqid)))
113 		goto out;
114 
115 	pn = puffs_pn_nodewalk(pu, nodecmp, &newqid);
116 	if (pn == NULL)
117 		pn = newp9pnode_qid(pu, &newqid, tfid);
118 	else
119 		proto_cc_clunkfid(pu, tfid, 0);
120 
121 	rv = do_getattr(pu, pn, &pn->pn_va);
122 	if (rv) {
123 		/* XXX */
124 		free(pn->pn_data);
125 		puffs_pn_put(pn);
126 		goto out;
127 	}
128 
129 	puffs_newinfo_setcookie(pni, pn);
130 	puffs_newinfo_setvtype(pni, pn->pn_va.va_type);
131 	puffs_newinfo_setsize(pni, pn->pn_va.va_size);
132 	puffs_newinfo_setrdev(pni, pn->pn_va.va_rdev);
133 
134  out:
135 	RETURN(rv);
136 }
137 
138 /*
139  * Problem is that 9P doesn't allow seeking into a directory.  So we
140  * maintain a list of active fids for any given directory.  They
141  * start living at the first read and exist either until the directory
142  * is closed or until they reach the end.
143  */
144 int
145 puffs9p_node_readdir(struct puffs_usermount *pu, void *opc, struct dirent *dent,
146 	off_t *readoff, size_t *reslen, const struct puffs_cred *pcr,
147 	int *eofflag, off_t *cookies, size_t *ncookies)
148 {
149 	AUTOVAR(pu);
150 	struct puffs_node *pn = opc;
151 	struct p9pnode *p9n = pn->pn_data;
152 	struct vattr va;
153 	struct dirfid *dfp;
154 	char *name;
155 	uint32_t count;
156 	uint16_t statsize;
157 
158 	rv = getdfwithoffset(pu, p9n, *readoff, &dfp);
159 	if (rv)
160 		goto out;
161 
162 	tag = NEXTTAG(p9p);
163 	p9pbuf_put_1(pb, P9PROTO_T_READ);
164 	p9pbuf_put_2(pb, tag);
165 	p9pbuf_put_4(pb, dfp->fid);
166 	p9pbuf_put_8(pb, *readoff);
167 	p9pbuf_put_4(pb, *reslen); /* XXX */
168 	GETRESPONSE(pb);
169 
170 	p9pbuf_get_4(pb, &count);
171 
172 	/*
173 	 * if count is 0, assume we at end-of-dir.  dfp is no longer
174 	 * useful, so nuke it
175 	 */
176 	if (count == 0) {
177 		*eofflag = 1;
178 		releasedf(pu, dfp);
179 		goto out;
180 	}
181 
182 	while (count > 0) {
183 		if ((rv = proto_getstat(pb, &va, &name, &statsize))) {
184 			/*
185 			 * If there was an error, it's unlikely we'll be
186 			 * coming back, so just nuke the dfp.  If we do
187 			 * come back for some strange reason, we'll just
188 			 * regen it.
189 			 */
190 			releasedf(pu, dfp);
191 			goto out;
192 		}
193 
194 		puffs_nextdent(&dent, name, va.va_fileid,
195 		    puffs_vtype2dt(va.va_type), reslen);
196 
197 		count -= statsize;
198 		*readoff += statsize;
199 		dfp->seekoff += statsize;
200 		free(name);
201 	}
202 
203 	storedf(p9n, dfp);
204 
205  out:
206 	RETURN(rv);
207 }
208 
209 int
210 puffs9p_node_setattr(struct puffs_usermount *pu, void *opc,
211 	const struct vattr *va, const struct puffs_cred *pcr)
212 {
213 	AUTOVAR(pu);
214 	struct puffs_node *pn = opc;
215 	struct p9pnode *p9n = pn->pn_data;
216 
217 	p9pbuf_put_1(pb, P9PROTO_T_WSTAT);
218 	p9pbuf_put_2(pb, tag);
219 	p9pbuf_put_4(pb, p9n->fid_base);
220 	proto_make_stat(pb, va, NULL, pn->pn_va.va_type);
221 	GETRESPONSE(pb);
222 
223 	if (p9pbuf_get_type(pb) != P9PROTO_R_WSTAT)
224 		rv = EPROTO;
225 
226  out:
227 	RETURN(rv);
228 }
229 
230 /*
231  * Ok, time to get clever.  There are two possible cases: we are
232  * opening a file or we are opening a directory.
233  *
234  * If it's a directory, don't bother opening it here, but rather
235  * wait until readdir, since it's probable we need to be able to
236  * open a directory there in any case.
237  *
238  * If it's a regular file, open it here with whatever credentials
239  * we happen to have.   Let the upper layers of the kernel worry
240  * about permission control.
241  */
242 int
243 puffs9p_node_open(struct puffs_usermount *pu, void *opc, int mode,
244 	const struct puffs_cred *pcr)
245 {
246 	struct puffs_cc *pcc = puffs_cc_getcc(pu);
247 	struct puffs9p *p9p = puffs_getspecific(pu);
248 	struct puffs_node *pn = opc;
249 	struct p9pnode *p9n = pn->pn_data;
250 	p9pfid_t nfid;
251 	int error = 0;
252 
253 	puffs_setback(pcc, PUFFS_SETBACK_INACT_N1);
254 	if (pn->pn_va.va_type != VDIR) {
255 		if (mode & FREAD && p9n->fid_read == P9P_INVALFID) {
256 			nfid = NEXTFID(p9p);
257 			error = proto_cc_open(pu, p9n->fid_base, nfid,
258 			    P9PROTO_OMODE_READ);
259 			if (error)
260 				return error;
261 			p9n->fid_read = nfid;
262 		}
263 		if (mode & FWRITE && p9n->fid_write == P9P_INVALFID) {
264 			nfid = NEXTFID(p9p);
265 			error = proto_cc_open(pu, p9n->fid_base, nfid,
266 			    P9PROTO_OMODE_WRITE);
267 			if (error)
268 				return error;
269 			p9n->fid_write = nfid;
270 		}
271 	}
272 
273 	return 0;
274 }
275 
276 int
277 puffs9p_node_inactive(struct puffs_usermount *pu, void *opc)
278 {
279 	struct puffs_node *pn = opc;
280 	struct p9pnode *p9n = pn->pn_data;
281 
282 	if (pn->pn_va.va_type == VDIR) {
283 		nukealldf(pu, p9n);
284 	} else  {
285 		if (p9n->fid_read != P9P_INVALFID) {
286 			proto_cc_clunkfid(pu, p9n->fid_read, 0);
287 			p9n->fid_read = P9P_INVALFID;
288 		}
289 		if (p9n->fid_write != P9P_INVALFID) {
290 			proto_cc_clunkfid(pu, p9n->fid_write, 0);
291 			p9n->fid_write = P9P_INVALFID;
292 		}
293 	}
294 
295 	return 0;
296 }
297 
298 int
299 puffs9p_node_read(struct puffs_usermount *pu, void *opc, uint8_t *buf,
300 	off_t offset, size_t *resid, const struct puffs_cred *pcr,
301 	int ioflag)
302 {
303 	AUTOVAR(pu);
304 	struct puffs_node *pn = opc;
305 	struct p9pnode *p9n = pn->pn_data;
306 	uint32_t count;
307 	size_t nread;
308 
309 	nread = 0;
310 	while (*resid > 0) {
311 		p9pbuf_put_1(pb, P9PROTO_T_READ);
312 		p9pbuf_put_2(pb, tag);
313 		p9pbuf_put_4(pb, p9n->fid_read);
314 		p9pbuf_put_8(pb, offset+nread);
315 		p9pbuf_put_4(pb, MIN((uint32_t)*resid,p9p->maxreq-24));
316 		GETRESPONSE(pb);
317 
318 		if (p9pbuf_get_type(pb) != P9PROTO_R_READ) {
319 			rv = EPROTO;
320 			break;
321 		}
322 
323 		p9pbuf_get_4(pb, &count);
324 		if ((rv = p9pbuf_read_data(pb, buf + nread, count)))
325 			break;
326 
327 		*resid -= count;
328 		nread += count;
329 
330 		p9pbuf_recycleout(pb);
331 	}
332 
333  out:
334 	RETURN(rv);
335 }
336 
337 int
338 puffs9p_node_write(struct puffs_usermount *pu, void *opc, uint8_t *buf,
339 	off_t offset, size_t *resid, const struct puffs_cred *cred,
340 	int ioflag)
341 {
342 	AUTOVAR(pu);
343 	struct puffs_node *pn = opc;
344 	struct p9pnode *p9n = pn->pn_data;
345 	uint32_t chunk, count;
346 	size_t nwrite;
347 
348 	if (ioflag & PUFFS_IO_APPEND)
349 		offset = pn->pn_va.va_size;
350 
351 	nwrite = 0;
352 	while (*resid > 0) {
353 		chunk = MIN(*resid, p9p->maxreq-32);
354 
355 		p9pbuf_put_1(pb, P9PROTO_T_WRITE);
356 		p9pbuf_put_2(pb, tag);
357 		p9pbuf_put_4(pb, p9n->fid_write);
358 		p9pbuf_put_8(pb, offset+nwrite);
359 		p9pbuf_put_4(pb, chunk);
360 		p9pbuf_write_data(pb, buf+nwrite, chunk);
361 		GETRESPONSE(pb);
362 
363 		if (p9pbuf_get_type(pb) != P9PROTO_R_WRITE) {
364 			rv = EPROTO;
365 			break;
366 		}
367 
368 		p9pbuf_get_4(pb, &count);
369 		*resid -= count;
370 		nwrite += count;
371 
372 		if (count != chunk) {
373 			rv = EPROTO;
374 			break;
375 		}
376 
377 		p9pbuf_recycleout(pb);
378 	}
379 
380  out:
381 	RETURN(rv);
382 }
383 
384 static int
385 nodecreate(struct puffs_usermount *pu, struct puffs_node *pn,
386 	struct puffs_newinfo *pni, const char *name,
387 	const struct vattr *vap, uint32_t dirbit)
388 {
389 	AUTOVAR(pu);
390 	struct puffs_node *pn_new;
391 	struct p9pnode *p9n = pn->pn_data;
392 	p9pfid_t nfid = NEXTFID(p9p);
393 	struct qid9p nqid;
394 	int tries = 0;
395 
396  again:
397 	if (++tries > 5) {
398 		rv = EPROTO;
399 		goto out;
400 	}
401 
402 	rv = proto_cc_dupfid(pu, p9n->fid_base, nfid);
403 	if (rv)
404 		goto out;
405 
406 	p9pbuf_put_1(pb, P9PROTO_T_CREATE);
407 	p9pbuf_put_2(pb, tag);
408 	p9pbuf_put_4(pb, nfid);
409 	p9pbuf_put_str(pb, name);
410 	p9pbuf_put_4(pb, dirbit | (vap->va_mode & 0777));
411 	p9pbuf_put_1(pb, 0);
412 	GETRESPONSE(pb);
413 
414 	rv = proto_expect_qid(pb, P9PROTO_R_CREATE, &nqid);
415 	if (rv)
416 		goto out;
417 
418 	/*
419 	 * Now, little problem here: create returns an *open* fid.
420 	 * So, clunk it and walk the parent directory to get a fid
421 	 * which is not open for I/O yet.
422 	 */
423 	proto_cc_clunkfid(pu, nfid, 0);
424 	nfid = NEXTFID(p9p);
425 
426 	p9pbuf_recycleout(pb);
427 	p9pbuf_put_1(pb, P9PROTO_T_WALK);
428 	p9pbuf_put_2(pb, tag);
429 	p9pbuf_put_4(pb, p9n->fid_base);
430 	p9pbuf_put_4(pb, nfid);
431 	p9pbuf_put_2(pb, 1);
432 	p9pbuf_put_str(pb, name);
433 	GETRESPONSE(pb);
434 
435 	/*
436 	 * someone removed it already? try again
437 	 * note: this is kind of lose/lose
438 	 */
439 	if (p9pbuf_get_type(pb) != P9PROTO_R_WALK)
440 		goto again;
441 
442 	pn_new = newp9pnode_va(pu, vap, nfid);
443 	qid2vattr(&pn_new->pn_va, &nqid);
444 	puffs_newinfo_setcookie(pni, pn_new);
445 
446  out:
447 	RETURN(rv);
448 }
449 
450 int
451 puffs9p_node_create(struct puffs_usermount *pu, void *opc, struct puffs_newinfo *pni,
452 	const struct puffs_cn *pcn, const struct vattr *va)
453 {
454 
455 	return nodecreate(pu, opc, pni, pcn->pcn_name, va, 0);
456 }
457 
458 int
459 puffs9p_node_mkdir(struct puffs_usermount *pu, void *opc, struct puffs_newinfo *pni,
460 	const struct puffs_cn *pcn, const struct vattr *va)
461 {
462 
463 	return nodecreate(pu, opc, pni, pcn->pcn_name,
464 	    va, P9PROTO_CPERM_DIR);
465 }
466 
467 /*
468  * Need to be a bit clever again: the fid is clunked no matter if
469  * the remove succeeds or not.  Re-getting a fid would be way too
470  * difficult in case the remove failed for a valid reason (directory
471  * not empty etcetc.).  So walk ourselves another fid to prod the
472  * ice with.
473  */
474 static int
475 noderemove(struct puffs_usermount *pu, struct puffs_node *pn)
476 {
477 	AUTOVAR(pu);
478 	struct p9pnode *p9n = pn->pn_data;
479 	p9pfid_t testfid = NEXTFID(p9p);
480 
481 	rv = proto_cc_dupfid(pu, p9n->fid_base, testfid);
482 	if (rv)
483 		goto out;
484 
485 	p9pbuf_put_1(pb, P9PROTO_T_REMOVE);
486 	p9pbuf_put_2(pb, tag);
487 	p9pbuf_put_4(pb, testfid);
488 
489 	/*
490 	 * XXX: error handling isn't very robust, but doom is impending
491 	 * anyway, so just accept we're going belly up and play dead
492 	 */
493 	GETRESPONSE(pb);
494 
495 	if (p9pbuf_get_type(pb) != P9PROTO_R_REMOVE) {
496 		rv = EPROTO;
497 	} else {
498 		proto_cc_clunkfid(pu, p9n->fid_base, 0);
499 		p9n->fid_base = P9P_INVALFID;
500 		puffs_pn_remove(pn);
501 	}
502 
503  out:
504 	if (rv == 0)
505 		puffs_setback(pcc, PUFFS_SETBACK_NOREF_N2);
506 
507 	RETURN(rv);
508 }
509 
510 int
511 puffs9p_node_remove(struct puffs_usermount *pu, void *opc, void *targ,
512 	const struct puffs_cn *pcn)
513 {
514 	struct puffs_node *pn = targ;
515 
516 	if (pn->pn_va.va_type == VDIR)
517 		return EISDIR;
518 
519 	return noderemove(pu, pn);
520 }
521 
522 int
523 puffs9p_node_rmdir(struct puffs_usermount *pu, void *opc, void *targ,
524 	const struct puffs_cn *pcn)
525 {
526 	struct puffs_node *pn = targ;
527 
528 	if (pn->pn_va.va_type != VDIR)
529 		return ENOTDIR;
530 
531 	return noderemove(pu, pn);
532 }
533 
534 /*
535  * 9P supports renames only for files within a directory
536  * from what I could tell.  So just support in-directory renames
537  * for now.
538  */
539 int
540 puffs9p_node_rename(struct puffs_usermount *pu, void *opc, void *src,
541 	const struct puffs_cn *pcn_src, void *targ_dir, void *targ,
542 	const struct puffs_cn *pcn_targ)
543 {
544 	AUTOVAR(pu);
545 	struct puffs_node *pn_src = src;
546 	struct p9pnode *p9n_src = pn_src->pn_data;
547 
548 	if (opc != targ_dir) {
549 		rv = EOPNOTSUPP;
550 		goto out;
551 	}
552 
553 	/* 9P doesn't allow to overwrite in rename */
554 	if (targ) {
555 		struct puffs_node *pn_targ = targ;
556 
557 		rv = noderemove(pu, pn_targ->pn_data);
558 		if (rv)
559 			goto out;
560 	}
561 
562 	p9pbuf_put_1(pb, P9PROTO_T_WSTAT);
563 	p9pbuf_put_2(pb, tag);
564 	p9pbuf_put_4(pb, p9n_src->fid_base);
565 	proto_make_stat(pb, NULL, pcn_targ->pcn_name, pn_src->pn_va.va_type);
566 	GETRESPONSE(pb);
567 
568 	if (p9pbuf_get_type(pb) != P9PROTO_R_WSTAT)
569 		rv = EPROTO;
570 
571  out:
572 	RETURN(rv);
573 }
574 
575 /*
576  * - "here's one"
577  * - "9P"
578  * ~ "i'm not dead"
579  * - "you're not fooling anyone you know, you'll be stone dead in a minute
580  * - "he says he's not quite dead"
581  * - "isn't there anything you could do?"
582  * - *clunk*!
583  * - "thanks"
584  */
585 int
586 puffs9p_node_reclaim(struct puffs_usermount *pu, void *opc)
587 {
588 	struct puffs_node *pn = opc;
589 	struct p9pnode *p9n = pn->pn_data;
590 
591 	assert(LIST_EMPTY(&p9n->dir_openlist));
592 	assert(p9n->fid_read == P9P_INVALFID && p9n->fid_write == P9P_INVALFID);
593 
594 	proto_cc_clunkfid(pu, p9n->fid_base, 0);
595 	free(p9n);
596 	puffs_pn_put(pn);
597 
598 	return 0;
599 }
600