xref: /netbsd-src/usr.sbin/puffs/mount_psshfs/node.c (revision 3816d47b2c42fcd6e549e3407f842a5b1a1d23ad)
1 /*	$NetBSD: node.c,v 1.60 2010/01/07 21:05:50 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2006-2009  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 1.60 2010/01/07 21:05:50 pooka Exp $");
31 #endif /* !lint */
32 
33 #include <assert.h>
34 #include <errno.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 
38 #include "psshfs.h"
39 #include "sftp_proto.h"
40 
41 int
42 psshfs_node_lookup(struct puffs_usermount *pu, puffs_cookie_t opc,
43 	struct puffs_newinfo *pni, const struct puffs_cn *pcn)
44 {
45 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
46 	struct puffs_node *pn_dir = opc;
47 	struct psshfs_node *psn, *psn_dir = pn_dir->pn_data;
48 	struct puffs_node *pn;
49 	struct psshfs_dir *pd;
50 	struct vattr va;
51 	int rv;
52 
53 	if (PCNISDOTDOT(pcn)) {
54 		psn = psn_dir->parent->pn_data;
55 		psn->stat &= ~PSN_RECLAIMED;
56 
57 		puffs_newinfo_setcookie(pni, psn_dir->parent);
58 		puffs_newinfo_setvtype(pni, VDIR);
59 		return 0;
60 	}
61 
62 	rv = sftp_readdir(pu, pctx, pn_dir);
63 	if (rv) {
64 		if (rv != EPERM)
65 			return rv;
66 
67 		/*
68 		 * Can't read the directory.  We still might be
69 		 * able to find the node with getattr in -r+x dirs
70 		 */
71 		rv = getpathattr(pu, PCNPATH(pcn), &va);
72 		if (rv)
73 			return rv;
74 
75 		/* guess */
76 		if (va.va_type == VDIR)
77 			va.va_nlink = 2;
78 		else
79 			va.va_nlink = 1;
80 
81 		pn = allocnode(pu, pn_dir, pcn->pcn_name, &va);
82 		psn = pn->pn_data;
83 		psn->attrread = time(NULL);
84 	} else {
85 		pd = lookup(psn_dir->dir, psn_dir->dentnext, pcn->pcn_name);
86 		if (!pd) {
87 			return ENOENT;
88 		}
89 
90 		if (pd->entry)
91 			pn = pd->entry;
92 		else
93 			pn = makenode(pu, pn_dir, pd, &pd->va);
94 		psn = pn->pn_data;
95 	}
96 
97 	psn->stat &= ~PSN_RECLAIMED;
98 
99 	puffs_newinfo_setcookie(pni, pn);
100 	puffs_newinfo_setvtype(pni, pn->pn_va.va_type);
101 	puffs_newinfo_setsize(pni, pn->pn_va.va_size);
102 
103 	return 0;
104 }
105 
106 int
107 psshfs_node_getattr(struct puffs_usermount *pu, puffs_cookie_t opc,
108 	struct vattr *vap, const struct puffs_cred *pcr)
109 {
110 	struct puffs_node *pn = opc;
111 	int rv;
112 
113 	rv = getnodeattr(pu, pn);
114 	if (rv)
115 		return rv;
116 
117 	memcpy(vap, &pn->pn_va, sizeof(struct vattr));
118 
119 	return 0;
120 }
121 
122 int
123 psshfs_node_setattr(struct puffs_usermount *pu, puffs_cookie_t opc,
124 	const struct vattr *va, const struct puffs_cred *pcr)
125 {
126 	PSSHFSAUTOVAR(pu);
127 	struct vattr kludgeva;
128 	struct puffs_node *pn = opc;
129 
130 	psbuf_req_str(pb, SSH_FXP_SETSTAT, reqid, PNPATH(pn));
131 
132 	memcpy(&kludgeva, va, sizeof(struct vattr));
133 
134 	/* XXX: kludge due to openssh server implementation */
135 	if (va->va_atime.tv_sec != PUFFS_VNOVAL
136 	    && va->va_mtime.tv_sec == PUFFS_VNOVAL) {
137 		if (pn->pn_va.va_mtime.tv_sec != PUFFS_VNOVAL)
138 			kludgeva.va_mtime.tv_sec = pn->pn_va.va_mtime.tv_sec;
139 		else
140 			kludgeva.va_mtime.tv_sec = va->va_atime.tv_sec;
141 	}
142 	if (va->va_mtime.tv_sec != PUFFS_VNOVAL
143 	    && va->va_atime.tv_sec == PUFFS_VNOVAL) {
144 		if (pn->pn_va.va_atime.tv_sec != PUFFS_VNOVAL)
145 			kludgeva.va_atime.tv_sec = pn->pn_va.va_atime.tv_sec;
146 		else
147 			kludgeva.va_atime.tv_sec = va->va_mtime.tv_sec;
148 	}
149 
150 	psbuf_put_vattr(pb, &kludgeva, pctx);
151 	GETRESPONSE(pb, pctx->sshfd);
152 
153 	rv = psbuf_expect_status(pb);
154 	if (rv == 0)
155 		puffs_setvattr(&pn->pn_va, &kludgeva);
156 
157  out:
158 	PSSHFSRETURN(rv);
159 }
160 
161 int
162 psshfs_node_create(struct puffs_usermount *pu, puffs_cookie_t opc,
163 	struct puffs_newinfo *pni, const struct puffs_cn *pcn,
164 	const struct vattr *va)
165 {
166 	PSSHFSAUTOVAR(pu);
167 	struct puffs_node *pn = opc;
168 	struct puffs_node *pn_new;
169 	char *fhand = NULL;
170 	uint32_t fhandlen;
171 
172 	/* Create node on server first */
173 	psbuf_req_str(pb, SSH_FXP_OPEN, reqid, PCNPATH(pcn));
174 	psbuf_put_4(pb, SSH_FXF_WRITE | SSH_FXF_CREAT | SSH_FXF_TRUNC);
175 	psbuf_put_vattr(pb, va, pctx);
176 	GETRESPONSE(pb, pctx->sshfd);
177 	rv = psbuf_expect_handle(pb, &fhand, &fhandlen);
178 	if (rv)
179 		goto out;
180 
181 	/*
182 	 * Do *not* create the local node before getting a response
183 	 * from the server.  Otherwise we might screw up consistency,
184 	 * namely that the node can be looked up before create has
185 	 * returned (mind you, the kernel will unlock the directory
186 	 * before the create call from userspace returns).
187 	 */
188 	pn_new = allocnode(pu, pn, pcn->pcn_name, va);
189 	if (!pn_new) {
190 		struct puffs_framebuf *pb2 = psbuf_makeout();
191 		reqid = NEXTREQ(pctx);
192 		psbuf_req_str(pb2, SSH_FXP_REMOVE, reqid, PCNPATH(pcn));
193 		JUSTSEND(pb2, pctx->sshfd);
194 		rv = ENOMEM;
195 	}
196 
197 	if (pn_new)
198 		puffs_newinfo_setcookie(pni, pn_new);
199 
200 	reqid = NEXTREQ(pctx);
201 	psbuf_recycleout(pb);
202 	psbuf_req_data(pb, SSH_FXP_CLOSE, reqid, fhand, fhandlen);
203 	JUSTSEND(pb, pctx->sshfd);
204 	free(fhand);
205 	return rv;
206 
207  out:
208 	free(fhand);
209 	PSSHFSRETURN(rv);
210 }
211 
212 /*
213  * Open a file handle.  This is used for read and write.  We do not
214  * wait here for the success or failure of this operation.  This is
215  * because otherwise opening and closing file handles would block
216  * reading potentially cached information.  Rather, we defer the wait
217  * to read/write and therefore allow cached access without a wait.
218  *
219  * If we have not yet succesfully opened a type of handle, we do wait
220  * here.  Also, if a lazy open fails, we revert back to the same
221  * state of waiting.
222  */
223 int
224 psshfs_node_open(struct puffs_usermount *pu, puffs_cookie_t opc, int mode,
225 	const struct puffs_cred *pcr)
226 {
227 	struct puffs_cc *pcc = puffs_cc_getcc(pu);
228 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
229 	struct puffs_framebuf *pb, *pb2;
230 	struct vattr va;
231 	struct puffs_node *pn = opc;
232 	struct psshfs_node *psn = pn->pn_data;
233 	uint32_t reqid;
234 	int didread, didwrite;
235 	int rv = 0;
236 
237 	if (pn->pn_va.va_type == VDIR)
238 		return 0;
239 
240 	puffs_setback(pcc, PUFFS_SETBACK_INACT_N1);
241 	puffs_vattr_null(&va);
242 	didread = didwrite = 0;
243 	if (mode & FREAD && psn->fhand_r == NULL && psn->lazyopen_r == NULL) {
244 		pb = psbuf_makeout();
245 
246 		reqid = NEXTREQ(pctx);
247 		psbuf_req_str(pb, SSH_FXP_OPEN, reqid, PNPATH(pn));
248 		psbuf_put_4(pb, SSH_FXF_READ);
249 		psbuf_put_vattr(pb, &va, pctx);
250 
251 		if (puffs_framev_enqueue_cb(pu, pctx->sshfd_data, pb,
252 		    lazyopen_rresp, psn, 0) == -1) {
253 			rv = errno;
254 			puffs_framebuf_destroy(pb);
255 			goto out;
256 		}
257 
258 		psn->lazyopen_r = pb;
259 		didread = 1;
260 	}
261 	if (mode & FWRITE && psn->fhand_w == NULL && psn->lazyopen_w == NULL) {
262 		pb2 = psbuf_makeout();
263 
264 		reqid = NEXTREQ(pctx);
265 		psbuf_req_str(pb2, SSH_FXP_OPEN, reqid, PNPATH(pn));
266 		psbuf_put_4(pb2, SSH_FXF_WRITE);
267 		psbuf_put_vattr(pb2, &va, pctx);
268 
269 		if (puffs_framev_enqueue_cb(pu, pctx->sshfd_data, pb2,
270 		    lazyopen_wresp, psn, 0) == -1) {
271 			rv = errno;
272 			puffs_framebuf_destroy(pb2);
273 			goto out;
274 		}
275 
276 		psn->lazyopen_w = pb2;
277 		didwrite = 1;
278 	}
279 	psn->stat &= ~PSN_HANDLECLOSE;
280 
281  out:
282 	/* wait? */
283 	if (didread && (psn->stat & PSN_DOLAZY_R) == 0) {
284 		assert(psn->lazyopen_r);
285 
286 		rv = puffs_framev_framebuf_ccpromote(psn->lazyopen_r, pcc);
287 		lazyopen_rresp(pu, psn->lazyopen_r, psn, rv);
288 		if (psn->fhand_r) {
289 			psn->stat |= PSN_DOLAZY_R;
290 		} else {
291 			if (psn->lazyopen_err_r)
292 				return psn->lazyopen_err_r;
293 			return EINVAL;
294 		}
295 	}
296 
297 	/* wait? */
298 	if (didwrite && (psn->stat & PSN_DOLAZY_W) == 0) {
299 		assert(psn->lazyopen_w);
300 
301 		rv = puffs_framev_framebuf_ccpromote(psn->lazyopen_w, pcc);
302 		lazyopen_wresp(pu, psn->lazyopen_w, psn, rv);
303 		if (psn->fhand_w) {
304 			psn->stat |= PSN_DOLAZY_W;
305 		} else {
306 			if (psn->lazyopen_err_w)
307 				return psn->lazyopen_err_w;
308 			return EINVAL;
309 		}
310 	}
311 
312 	return rv;
313 }
314 
315 int
316 psshfs_node_inactive(struct puffs_usermount *pu, puffs_cookie_t opc)
317 {
318 	struct puffs_node *pn = opc;
319 
320 	closehandles(pu, pn->pn_data, HANDLE_READ | HANDLE_WRITE);
321 	return 0;
322 }
323 
324 int
325 psshfs_node_readdir(struct puffs_usermount *pu, puffs_cookie_t opc,
326 	struct dirent *dent, off_t *readoff, size_t *reslen,
327 	const struct puffs_cred *pcr, int *eofflag,
328 	off_t *cookies, size_t *ncookies)
329 {
330 	struct puffs_cc *pcc = puffs_cc_getcc(pu);
331 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
332 	struct puffs_node *pn = opc;
333 	struct psshfs_node *psn = pn->pn_data;
334 	struct psshfs_dir *pd;
335 	size_t i;
336 	int rv, set_readdir;
337 
338  restart:
339 	if (psn->stat & PSN_READDIR) {
340 		struct psshfs_wait pw;
341 
342 		set_readdir = 0;
343 		pw.pw_cc = pcc;
344 		pw.pw_type = PWTYPE_READDIR;
345 		TAILQ_INSERT_TAIL(&psn->pw, &pw, pw_entries);
346 		puffs_cc_yield(pcc);
347 		goto restart;
348 	} else {
349 		psn->stat |= PSN_READDIR;
350 		set_readdir = 1;
351 	}
352 
353 	*ncookies = 0;
354 	rv = sftp_readdir(pu, pctx, pn);
355 	if (rv)
356 		goto out;
357 
358 	/* find next dirent */
359 	for (i = *readoff;;i++) {
360 		if (i >= psn->dentnext)
361 			goto out;
362 		pd = &psn->dir[i];
363 		if (pd->valid)
364 			break;
365 	}
366 
367 	for (;;) {
368 		*readoff = i;
369 		if (!puffs_nextdent(&dent, pd->entryname,
370 		    pd->va.va_fileid, puffs_vtype2dt(pd->va.va_type), reslen)) {
371 			rv = 0;
372 			goto out;
373 		}
374 
375 		/* find next entry, store possible nfs key */
376 		do {
377 			if (++i >= psn->dentnext)
378 				goto out;
379 			pd = &psn->dir[i];
380 		} while (pd->valid == 0);
381 		PUFFS_STORE_DCOOKIE(cookies, ncookies, (off_t)i);
382 	}
383 
384  out:
385 	if (rv == 0) {
386 		if (i >= psn->dentnext)
387 			*eofflag = 1;
388 
389 		*readoff = i;
390 	}
391 
392 	if (set_readdir) {
393 		struct psshfs_wait *pw;
394 
395 		/* all will likely run to completion because of cache */
396 		TAILQ_FOREACH(pw, &psn->pw, pw_entries) {
397 			assert(pw->pw_type == PWTYPE_READDIR);
398 			puffs_cc_schedule(pw->pw_cc);
399 			TAILQ_REMOVE(&psn->pw, pw, pw_entries);
400 		}
401 
402 		psn->stat &= ~PSN_READDIR;
403 	}
404 
405 	return rv;
406 }
407 
408 int
409 psshfs_node_read(struct puffs_usermount *pu, puffs_cookie_t opc, uint8_t *buf,
410 	off_t offset, size_t *resid, const struct puffs_cred *pcr,
411 	int ioflag)
412 {
413 	PSSHFSAUTOVAR(pu);
414 	struct puffs_node *pn = opc;
415 	struct psshfs_node *psn = pn->pn_data;
416 	struct psshfs_wait *pwp;
417 	uint32_t readlen;
418 
419 	if (pn->pn_va.va_type == VDIR) {
420 		rv = EISDIR;
421 		goto farout;
422 	}
423 
424 	/* check that a lazyopen didn't fail */
425 	if (!psn->fhand_r && !psn->lazyopen_r) {
426 		rv = psn->lazyopen_err_r;
427 		goto farout;
428 	}
429 
430 	/* if someone is already waiting for the lazyopen, "just" wait */
431 	if (psn->stat & PSN_LAZYWAIT_R) {
432 		struct psshfs_wait pw;
433 
434 		assert(psn->lazyopen_r);
435 
436 		pw.pw_cc = pcc;
437 		pw.pw_type = PWTYPE_READ1;
438 		TAILQ_INSERT_TAIL(&psn->pw, &pw, pw_entries);
439 		puffs_cc_yield(pcc);
440 	}
441 
442 	/* if lazyopening, wait for the result */
443 	if (psn->lazyopen_r) {
444 		psn->stat |= PSN_LAZYWAIT_R;
445 		rv = puffs_framev_framebuf_ccpromote(psn->lazyopen_r, pcc);
446 		lazyopen_rresp(pu, psn->lazyopen_r, psn, rv);
447 
448 		/* schedule extra waiters */
449 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
450 			if (pwp->pw_type == PWTYPE_READ1) {
451 				puffs_cc_schedule(pwp->pw_cc);
452 				TAILQ_REMOVE(&psn->pw, pwp, pw_entries);
453 			}
454 		psn->stat &= ~PSN_LAZYWAIT_R;
455 
456 		if ((rv = psn->lazyopen_err_r) != 0)
457 			goto farout;
458 	}
459 
460 	/* if there is still no handle, just refuse to live with this */
461 	if (!psn->fhand_r) {
462 		rv = EINVAL;
463 		goto farout;
464 	}
465 
466 	readlen = *resid;
467 	psbuf_req_data(pb, SSH_FXP_READ, reqid, psn->fhand_r, psn->fhand_r_len);
468 	psbuf_put_8(pb, offset);
469 	psbuf_put_4(pb, readlen);
470 
471 	/*
472 	 * Do this *after* accessing the file, the handle might not
473 	 * exist after blocking.
474 	 */
475 	if (max_reads && ++psn->readcount > max_reads) {
476 		struct psshfs_wait pw;
477 
478 		pw.pw_cc = pcc;
479 		pw.pw_type = PWTYPE_READ2;
480 		TAILQ_INSERT_TAIL(&psn->pw, &pw, pw_entries);
481 		puffs_cc_yield(pcc);
482 	}
483 
484 	GETRESPONSE(pb, pctx->sshfd_data);
485 
486 	rv = psbuf_do_data(pb, buf, &readlen);
487 	if (rv == 0)
488 		*resid -= readlen;
489 
490  out:
491 	if (max_reads && --psn->readcount >= max_reads) {
492 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
493 			if (pwp->pw_type == PWTYPE_READ2)
494 				break;
495 		assert(pwp != NULL);
496 		puffs_cc_schedule(pwp->pw_cc);
497 		TAILQ_REMOVE(&psn->pw, pwp, pw_entries);
498 	}
499 
500  farout:
501 	/* check if we need a lazyclose */
502 	if (psn->stat & PSN_HANDLECLOSE && psn->fhand_r) {
503 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
504 			if (pwp->pw_type == PWTYPE_READ1)
505 				break;
506 		if (pwp == NULL)
507 			closehandles(pu, psn, HANDLE_READ);
508 	}
509 	PSSHFSRETURN(rv);
510 }
511 
512 /* XXX: we should getattr for size */
513 int
514 psshfs_node_write(struct puffs_usermount *pu, puffs_cookie_t opc, uint8_t *buf,
515 	off_t offset, size_t *resid, const struct puffs_cred *cred,
516 	int ioflag)
517 {
518 	PSSHFSAUTOVAR(pu);
519 	struct psshfs_wait *pwp;
520 	struct puffs_node *pn = opc;
521 	struct psshfs_node *psn = pn->pn_data;
522 	uint32_t writelen;
523 
524 	if (pn->pn_va.va_type == VDIR) {
525 		rv = EISDIR;
526 		goto out;
527 	}
528 
529 	/* check that a lazyopen didn't fail */
530 	if (!psn->fhand_w && !psn->lazyopen_w) {
531 		rv = psn->lazyopen_err_w;
532 		goto out;
533 	}
534 
535 	if (psn->stat & PSN_LAZYWAIT_W) {
536 		struct psshfs_wait pw;
537 
538 		assert(psn->lazyopen_w);
539 
540 		pw.pw_cc = pcc;
541 		pw.pw_type = PWTYPE_WRITE;
542 		TAILQ_INSERT_TAIL(&psn->pw, &pw, pw_entries);
543 		puffs_cc_yield(pcc);
544 	}
545 
546 	/*
547 	 * If lazyopening, wait for the result.
548 	 * There can still be more than oen writer at a time in case
549 	 * the kernel issues write FAFs.
550 	 */
551 	if (psn->lazyopen_w) {
552 		psn->stat |= PSN_LAZYWAIT_W;
553 		rv = puffs_framev_framebuf_ccpromote(psn->lazyopen_w, pcc);
554 		lazyopen_wresp(pu, psn->lazyopen_w, psn, rv);
555 
556 		/* schedule extra waiters */
557 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
558 			if (pwp->pw_type == PWTYPE_WRITE) {
559 				puffs_cc_schedule(pwp->pw_cc);
560 				TAILQ_REMOVE(&psn->pw, pwp, pw_entries);
561 			}
562 		psn->stat &= ~PSN_LAZYWAIT_W;
563 
564 		if ((rv = psn->lazyopen_err_w) != 0)
565 			goto out;
566 	}
567 
568 	if (!psn->fhand_w) {
569 		abort();
570 		rv = EINVAL;
571 		goto out;
572 	}
573 
574 	writelen = *resid;
575 	psbuf_req_data(pb, SSH_FXP_WRITE, reqid, psn->fhand_w,psn->fhand_w_len);
576 	psbuf_put_8(pb, offset);
577 	psbuf_put_data(pb, buf, writelen);
578 	GETRESPONSE(pb, pctx->sshfd_data);
579 
580 	rv = psbuf_expect_status(pb);
581 	if (rv == 0)
582 		*resid = 0;
583 
584 	if (pn->pn_va.va_size < (uint64_t)offset + writelen)
585 		pn->pn_va.va_size = offset + writelen;
586 
587  out:
588 	/* check if we need a lazyclose */
589 	if (psn->stat & PSN_HANDLECLOSE && psn->fhand_w) {
590 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
591 			if (pwp->pw_type == PWTYPE_WRITE)
592 				break;
593 		if (pwp == NULL)
594 			closehandles(pu, psn, HANDLE_WRITE);
595 	}
596 	PSSHFSRETURN(rv);
597 }
598 
599 int
600 psshfs_node_readlink(struct puffs_usermount *pu, puffs_cookie_t opc,
601 	const struct puffs_cred *cred, char *linkvalue, size_t *linklen)
602 {
603 	PSSHFSAUTOVAR(pu);
604 	struct puffs_node *pn = opc;
605 	struct psshfs_node *psn = pn->pn_data;
606 	uint32_t count;
607 
608 	if (pctx->protover < 3) {
609 		rv = EOPNOTSUPP;
610 		goto out;
611 	}
612 
613 	/*
614 	 * check if we can use a cached version
615 	 *
616 	 * XXX: we might end up reading the same link multiple times
617 	 * from the server if we get many requests at once, but that's
618 	 * quite harmless as this routine is reentrant.
619 	 */
620 	if (psn->symlink && !REFRESHTIMEOUT(pctx, time(NULL) - psn->slread))
621 		goto copy;
622 
623 	if (psn->symlink) {
624 		free(psn->symlink);
625 		psn->symlink = NULL;
626 		psn->slread = 0;
627 	}
628 
629 	psbuf_req_str(pb, SSH_FXP_READLINK, reqid, PNPATH(pn));
630 	GETRESPONSE(pb, pctx->sshfd);
631 
632 	rv = psbuf_expect_name(pb, &count);
633 	if (rv)
634 		goto out;
635 	if (count != 1) {
636 		rv = EPROTO;
637 		goto out;
638 	}
639 
640 	rv = psbuf_get_str(pb, &psn->symlink, NULL);
641 	if (rv)
642 		goto out;
643 	psn->slread = time(NULL);
644 
645  copy:
646 	*linklen = strlen(psn->symlink);
647 	(void) memcpy(linkvalue, psn->symlink, *linklen);
648 
649  out:
650 	PSSHFSRETURN(rv);
651 }
652 
653 static int
654 doremove(struct puffs_usermount *pu, struct puffs_node *pn_dir,
655 	struct puffs_node *pn, const char *name)
656 {
657 	PSSHFSAUTOVAR(pu);
658 	int op;
659 
660 	if (pn->pn_va.va_type == VDIR)
661 		op = SSH_FXP_RMDIR;
662 	else
663 		op = SSH_FXP_REMOVE;
664 
665 	psbuf_req_str(pb, op, reqid, PNPATH(pn));
666 	GETRESPONSE(pb, pctx->sshfd);
667 
668 	rv = psbuf_expect_status(pb);
669 	if (rv == 0)
670 		nukenode(pn, name, 0);
671 
672  out:
673 	PSSHFSRETURN(rv);
674 }
675 
676 int
677 psshfs_node_remove(struct puffs_usermount *pu, puffs_cookie_t opc,
678 	puffs_cookie_t targ, const struct puffs_cn *pcn)
679 {
680 	struct puffs_node *pn_targ = targ;
681 	int rv;
682 
683 	assert(pn_targ->pn_va.va_type != VDIR);
684 
685 	rv = doremove(pu, opc, targ, pcn->pcn_name);
686 	if (rv == 0)
687 		puffs_setback(puffs_cc_getcc(pu), PUFFS_SETBACK_NOREF_N2);
688 
689 	return rv;
690 }
691 
692 int
693 psshfs_node_rmdir(struct puffs_usermount *pu, puffs_cookie_t opc,
694 	puffs_cookie_t targ, const struct puffs_cn *pcn)
695 {
696 	struct puffs_node *pn_targ = targ;
697 	int rv;
698 
699 	assert(pn_targ->pn_va.va_type == VDIR);
700 
701 	rv = doremove(pu, opc, targ, pcn->pcn_name);
702 	if (rv == 0)
703 		puffs_setback(puffs_cc_getcc(pu), PUFFS_SETBACK_NOREF_N2);
704 
705 	return rv;
706 }
707 
708 int
709 psshfs_node_mkdir(struct puffs_usermount *pu, puffs_cookie_t opc,
710 	struct puffs_newinfo *pni, const struct puffs_cn *pcn,
711 	const struct vattr *va)
712 {
713 	PSSHFSAUTOVAR(pu);
714 	struct puffs_node *pn = opc;
715 	struct puffs_node *pn_new;
716 
717 	psbuf_req_str(pb, SSH_FXP_MKDIR, reqid, PCNPATH(pcn));
718 	psbuf_put_vattr(pb, va, pctx);
719 	GETRESPONSE(pb, pctx->sshfd);
720 
721 	rv = psbuf_expect_status(pb);
722 	if (rv)
723 		goto out;
724 
725 	pn_new = allocnode(pu, pn, pcn->pcn_name, va);
726 	if (pn_new) {
727 		puffs_newinfo_setcookie(pni, pn_new);
728 	} else {
729 		struct puffs_framebuf *pb2 = psbuf_makeout();
730 		reqid = NEXTREQ(pctx);
731 		psbuf_recycleout(pb2);
732 		psbuf_req_str(pb2, SSH_FXP_RMDIR, reqid, PCNPATH(pcn));
733 		JUSTSEND(pb2, pctx->sshfd);
734 		rv = ENOMEM;
735 	}
736 
737  out:
738 	PSSHFSRETURN(rv);
739 }
740 
741 int
742 psshfs_node_symlink(struct puffs_usermount *pu, puffs_cookie_t opc,
743 	struct puffs_newinfo *pni, const struct puffs_cn *pcn,
744 	const struct vattr *va, const char *link_target)
745 {
746 	PSSHFSAUTOVAR(pu);
747 	struct puffs_node *pn = opc;
748 	struct puffs_node *pn_new;
749 
750 	if (pctx->protover < 3) {
751 		rv = EOPNOTSUPP;
752 		goto out;
753 	}
754 
755 	/*
756 	 * XXX: ietf says: source, target.  openssh says: ietf who?
757 	 * Let's go with openssh and build quirk tables later if we care
758 	 */
759 	psbuf_req_str(pb, SSH_FXP_SYMLINK, reqid, link_target);
760 	psbuf_put_str(pb, PCNPATH(pcn));
761 	GETRESPONSE(pb, pctx->sshfd);
762 
763 	rv = psbuf_expect_status(pb);
764 	if (rv)
765 		goto out;
766 
767 	pn_new = allocnode(pu, pn, pcn->pcn_name, va);
768 	if (pn_new) {
769 		puffs_newinfo_setcookie(pni, pn_new);
770 	} else {
771 		struct puffs_framebuf *pb2 = psbuf_makeout();
772 		reqid = NEXTREQ(pctx);
773 		psbuf_recycleout(pb2);
774 		psbuf_req_str(pb2, SSH_FXP_REMOVE, reqid, PCNPATH(pcn));
775 		JUSTSEND(pb2, pctx->sshfd);
776 		rv = ENOMEM;
777 	}
778 
779  out:
780 	PSSHFSRETURN(rv);
781 }
782 
783 int
784 psshfs_node_rename(struct puffs_usermount *pu, puffs_cookie_t opc,
785 	puffs_cookie_t src, const struct puffs_cn *pcn_src,
786 	puffs_cookie_t targ_dir, puffs_cookie_t targ,
787 	const struct puffs_cn *pcn_targ)
788 {
789 	PSSHFSAUTOVAR(pu);
790 	struct puffs_node *pn_sf = src;
791 	struct puffs_node *pn_td = targ_dir, *pn_tf = targ;
792 	struct psshfs_node *psn_src = pn_sf->pn_data;
793 	struct psshfs_node *psn_targdir = pn_td->pn_data;
794 
795 	if (pctx->protover < 2) {
796 		rv = EOPNOTSUPP;
797 		goto out;
798 	}
799 
800 	if (pn_tf) {
801 		rv = doremove(pu, targ_dir, pn_tf, pcn_targ->pcn_name);
802 		if (rv)
803 			goto out;
804 	}
805 
806 	psbuf_req_str(pb, SSH_FXP_RENAME, reqid, PCNPATH(pcn_src));
807 	psbuf_put_str(pb, PCNPATH(pcn_targ));
808 	GETRESPONSE(pb, pctx->sshfd);
809 
810 	rv = psbuf_expect_status(pb);
811 	if (rv == 0) {
812 		struct psshfs_dir *pd;
813 
814 		/*
815 		 * XXX: interfaces didn't quite work with rename..
816 		 * the song remains the same.  go figure .. ;)
817 		 */
818 		nukenode(pn_sf, pcn_src->pcn_name, 0);
819 		pd = direnter(pn_td, pcn_targ->pcn_name);
820 		pd->entry = pn_sf;
821 		puffs_setvattr(&pd->va, &pn_sf->pn_va);
822 
823 		if (opc != targ_dir) {
824 			psn_targdir->childcount++;
825 			psn_src->parent = pn_td;
826 			if (pn_sf->pn_va.va_type == VDIR)
827 				pn_td->pn_va.va_nlink++;
828 		}
829 	}
830 
831  out:
832 	PSSHFSRETURN(rv);
833 }
834 
835 /*
836  * So this file system happened to be written in such a way that
837  * lookup for ".." is hard if we lose the in-memory node.  We'd
838  * need to recreate the entire directory structure from the root
839  * node up to the ".." node we're looking up.
840  *
841  * And since our entire fs structure is purely fictional (i.e. it's
842  * only in-memory, not fetchable from the server), the easiest way
843  * to deal with it is to not allow nodes with children to be
844  * reclaimed.
845  *
846  * If a node with children is being attempted to be reclaimed, we
847  * just mark it "reclaimed" but leave it as is until all its children
848  * have been reclaimed.  If a lookup for that node is done meanwhile,
849  * it will be found by lookup() and we just remove the "reclaimed"
850  * bit.
851  */
852 int
853 psshfs_node_reclaim(struct puffs_usermount *pu, puffs_cookie_t opc)
854 {
855 	struct puffs_node *pn = opc, *pn_next, *pn_root;
856 	struct psshfs_node *psn = pn->pn_data;
857 
858 	/*
859 	 * don't reclaim if we have file handle issued, otherwise
860 	 * we can't do fhtonode
861 	 */
862 	if (psn->stat & PSN_HASFH)
863 		return 0;
864 
865 	psn->stat |= PSN_RECLAIMED;
866 	pn_root = puffs_getroot(pu);
867 	for (; pn != pn_root; pn = pn_next) {
868 		psn = pn->pn_data;
869 		if ((psn->stat & PSN_RECLAIMED) == 0 || psn->childcount != 0)
870 			break;
871 
872 		pn_next = psn->parent;
873 		doreclaim(pn);
874 	}
875 
876 	return 0;
877 }
878