xref: /minix/lib/libpuffs/framebuf.c (revision 84d9c625)
1 /*	$NetBSD: framebuf.c,v 1.32 2012/06/25 22:32:47 abs Exp $	*/
2 
3 /*
4  * Copyright (c) 2007  Antti Kantee.  All Rights Reserved.
5  *
6  * Development of this software was supported by the
7  * Finnish Cultural Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
19  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32  * The event portion of this code is a twisty maze of pointers,
33  * flags, yields and continues.  Sincere aplogies.
34  */
35 
36 #include <sys/cdefs.h>
37 #if !defined(lint)
38 __RCSID("$NetBSD: framebuf.c,v 1.32 2012/06/25 22:32:47 abs Exp $");
39 #endif /* !lint */
40 
41 #include <sys/types.h>
42 #include <sys/queue.h>
43 
44 #include <assert.h>
45 #include <errno.h>
46 #include <poll.h>
47 #include <puffs.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <unistd.h>
51 
52 #include "puffs_priv.h"
53 
54 struct puffs_framebuf {
55 	struct puffs_cc *pcc;	/* pcc to continue with */
56 	/* OR */
57 	puffs_framev_cb fcb;	/* non-blocking callback */
58 	void *fcb_arg;		/* argument for previous */
59 
60 	uint8_t *buf;		/* buffer base */
61 	size_t len;		/* total length */
62 
63 	size_t offset;		/* cursor, telloff() */
64 	size_t maxoff;		/* maximum offset for data, tellsize() */
65 
66 	volatile int rv;	/* errno value */
67 
68 	int	istat;
69 
70 	TAILQ_ENTRY(puffs_framebuf) pfb_entries;
71 };
72 #define ISTAT_NODESTROY	0x01	/* indestructible by framebuf_destroy() */
73 #define ISTAT_INTERNAL	0x02	/* never leaves library			*/
74 #define ISTAT_NOREPLY	0x04	/* nuke after sending 			*/
75 #define ISTAT_DIRECT	0x08	/* receive directly, no moveinfo	*/
76 
77 #define ISTAT_ONQUEUE	ISTAT_NODESTROY	/* alias */
78 
79 #define PUFBUF_INCRALLOC 4096
80 #define PUFBUF_REMAIN(p) (p->len - p->offset)
81 
82 /* for poll/kqueue */
83 struct puffs_fbevent {
84 	struct puffs_cc	*pcc;
85 	int what;
86 	volatile int rv;
87 
88 	LIST_ENTRY(puffs_fbevent) pfe_entries;
89 };
90 
91 static struct puffs_fctrl_io *
getfiobyfd(struct puffs_usermount * pu,int fd)92 getfiobyfd(struct puffs_usermount *pu, int fd)
93 {
94 	struct puffs_fctrl_io *fio;
95 
96 	LIST_FOREACH(fio, &pu->pu_ios, fio_entries)
97 		if (fio->io_fd == fd)
98 			return fio;
99 	return NULL;
100 }
101 
102 struct puffs_framebuf *
puffs_framebuf_make(void)103 puffs_framebuf_make(void)
104 {
105 	struct puffs_framebuf *pufbuf;
106 
107 	pufbuf = malloc(sizeof(struct puffs_framebuf));
108 	if (pufbuf == NULL)
109 		return NULL;
110 	memset(pufbuf, 0, sizeof(struct puffs_framebuf));
111 
112 	pufbuf->buf = malloc(PUFBUF_INCRALLOC);
113 	if (pufbuf->buf == NULL) {
114 		free(pufbuf);
115 		return NULL;
116 	}
117 	pufbuf->len = PUFBUF_INCRALLOC;
118 
119 	puffs_framebuf_recycle(pufbuf);
120 	return pufbuf;
121 }
122 
123 void
puffs_framebuf_destroy(struct puffs_framebuf * pufbuf)124 puffs_framebuf_destroy(struct puffs_framebuf *pufbuf)
125 {
126 
127 	assert((pufbuf->istat & ISTAT_NODESTROY) == 0);
128 
129 	free(pufbuf->buf);
130 	free(pufbuf);
131 }
132 
133 void
puffs_framebuf_recycle(struct puffs_framebuf * pufbuf)134 puffs_framebuf_recycle(struct puffs_framebuf *pufbuf)
135 {
136 
137 	assert((pufbuf->istat & ISTAT_NODESTROY) == 0);
138 
139 	pufbuf->offset = 0;
140 	pufbuf->maxoff = 0;
141 	pufbuf->istat = 0;
142 }
143 
144 static int
reservespace(struct puffs_framebuf * pufbuf,size_t off,size_t wantsize)145 reservespace(struct puffs_framebuf *pufbuf, size_t off, size_t wantsize)
146 {
147 	size_t incr;
148 	void *nd;
149 
150 	if (off <= pufbuf->len && pufbuf->len - off >= wantsize)
151 		return 0;
152 
153 	for (incr = PUFBUF_INCRALLOC;
154 	    pufbuf->len + incr < off + wantsize;
155 	    incr += PUFBUF_INCRALLOC)
156 		continue;
157 
158 	nd = realloc(pufbuf->buf, pufbuf->len + incr);
159 	if (nd == NULL)
160 		return -1;
161 
162 	pufbuf->buf = nd;
163 	pufbuf->len += incr;
164 
165 	return 0;
166 }
167 
168 int
puffs_framebuf_dup(struct puffs_framebuf * pb,struct puffs_framebuf ** pbp)169 puffs_framebuf_dup(struct puffs_framebuf *pb, struct puffs_framebuf **pbp)
170 {
171 	struct puffs_framebuf *newpb;
172 
173 	newpb = puffs_framebuf_make();
174 	if (newpb == NULL) {
175 		errno = ENOMEM;
176 		return -1;
177 	}
178 	memcpy(newpb, pb, sizeof(struct puffs_framebuf));
179 
180 	newpb->buf = NULL;
181 	newpb->len = 0;
182 	if (reservespace(newpb, 0, pb->maxoff) == -1) {
183 		puffs_framebuf_destroy(newpb);
184 		return -1;
185 	}
186 
187 	memcpy(newpb->buf, pb->buf, pb->maxoff);
188 	newpb->istat = 0;
189 	*pbp = newpb;
190 
191 	return 0;
192 }
193 
194 int
puffs_framebuf_reserve_space(struct puffs_framebuf * pufbuf,size_t wantsize)195 puffs_framebuf_reserve_space(struct puffs_framebuf *pufbuf, size_t wantsize)
196 {
197 
198 	return reservespace(pufbuf, pufbuf->offset, wantsize);
199 }
200 
201 int
puffs_framebuf_putdata(struct puffs_framebuf * pufbuf,const void * data,size_t dlen)202 puffs_framebuf_putdata(struct puffs_framebuf *pufbuf,
203 	const void *data, size_t dlen)
204 {
205 
206 	if (PUFBUF_REMAIN(pufbuf) < dlen)
207 		if (puffs_framebuf_reserve_space(pufbuf, dlen) == -1)
208 			return -1;
209 
210 	memcpy(pufbuf->buf + pufbuf->offset, data, dlen);
211 	pufbuf->offset += dlen;
212 
213 	if (pufbuf->offset > pufbuf->maxoff)
214 		pufbuf->maxoff = pufbuf->offset;
215 
216 	return 0;
217 }
218 
219 int
puffs_framebuf_putdata_atoff(struct puffs_framebuf * pufbuf,size_t offset,const void * data,size_t dlen)220 puffs_framebuf_putdata_atoff(struct puffs_framebuf *pufbuf, size_t offset,
221 	const void *data, size_t dlen)
222 {
223 
224 	if (reservespace(pufbuf, offset, dlen) == -1)
225 		return -1;
226 
227 	memcpy(pufbuf->buf + offset, data, dlen);
228 
229 	if (offset + dlen > pufbuf->maxoff)
230 		pufbuf->maxoff = offset + dlen;
231 
232 	return 0;
233 }
234 
235 int
puffs_framebuf_getdata(struct puffs_framebuf * pufbuf,void * data,size_t dlen)236 puffs_framebuf_getdata(struct puffs_framebuf *pufbuf, void *data, size_t dlen)
237 {
238 
239 	if (pufbuf->maxoff < pufbuf->offset + dlen) {
240 		errno = ENOBUFS;
241 		return -1;
242 	}
243 
244 	memcpy(data, pufbuf->buf + pufbuf->offset, dlen);
245 	pufbuf->offset += dlen;
246 
247 	return 0;
248 }
249 
250 int
puffs_framebuf_getdata_atoff(struct puffs_framebuf * pufbuf,size_t offset,void * data,size_t dlen)251 puffs_framebuf_getdata_atoff(struct puffs_framebuf *pufbuf, size_t offset,
252 	void *data, size_t dlen)
253 {
254 
255 	if (pufbuf->maxoff < offset + dlen) {
256 		errno = ENOBUFS;
257 		return -1;
258 	}
259 
260 	memcpy(data, pufbuf->buf + offset, dlen);
261 	return 0;
262 }
263 
264 size_t
puffs_framebuf_telloff(struct puffs_framebuf * pufbuf)265 puffs_framebuf_telloff(struct puffs_framebuf *pufbuf)
266 {
267 
268 	return pufbuf->offset;
269 }
270 
271 size_t
puffs_framebuf_tellsize(struct puffs_framebuf * pufbuf)272 puffs_framebuf_tellsize(struct puffs_framebuf *pufbuf)
273 {
274 
275 	return pufbuf->maxoff;
276 }
277 
278 size_t
puffs_framebuf_remaining(struct puffs_framebuf * pufbuf)279 puffs_framebuf_remaining(struct puffs_framebuf *pufbuf)
280 {
281 
282 	return puffs_framebuf_tellsize(pufbuf) - puffs_framebuf_telloff(pufbuf);
283 }
284 
285 int
puffs_framebuf_seekset(struct puffs_framebuf * pufbuf,size_t newoff)286 puffs_framebuf_seekset(struct puffs_framebuf *pufbuf, size_t newoff)
287 {
288 
289 	if (reservespace(pufbuf, newoff, 0) == -1)
290 		return -1;
291 
292 	pufbuf->offset = newoff;
293 	return 0;
294 }
295 
296 int
puffs_framebuf_getwindow(struct puffs_framebuf * pufbuf,size_t winoff,void ** data,size_t * dlen)297 puffs_framebuf_getwindow(struct puffs_framebuf *pufbuf, size_t winoff,
298 	void **data, size_t *dlen)
299 {
300 	size_t winlen;
301 
302 #ifdef WINTESTING
303 	winlen = MIN(*dlen, 32);
304 #else
305 	winlen = *dlen;
306 #endif
307 
308 	if (reservespace(pufbuf, winoff, winlen) == -1)
309 		return -1;
310 
311 	*data = pufbuf->buf + winoff;
312 	if (pufbuf->maxoff < winoff + winlen)
313 		pufbuf->maxoff = winoff + winlen;
314 
315 	return 0;
316 }
317 
318 void *
puffs__framebuf_getdataptr(struct puffs_framebuf * pufbuf)319 puffs__framebuf_getdataptr(struct puffs_framebuf *pufbuf)
320 {
321 
322 	return pufbuf->buf;
323 }
324 
325 static void
errnotify(struct puffs_usermount * pu,struct puffs_framebuf * pufbuf,int error)326 errnotify(struct puffs_usermount *pu, struct puffs_framebuf *pufbuf, int error)
327 {
328 
329 	pufbuf->rv = error;
330 	if (pufbuf->pcc) {
331 		puffs__goto(pufbuf->pcc);
332 	} else if (pufbuf->fcb) {
333 		pufbuf->istat &= ~ISTAT_NODESTROY;
334 		pufbuf->fcb(pu, pufbuf, pufbuf->fcb_arg, error);
335 	} else {
336 		pufbuf->istat &= ~ISTAT_NODESTROY;
337 		puffs_framebuf_destroy(pufbuf);
338 	}
339 }
340 
341 #define GETFIO(fd)							\
342 do {									\
343 	fio = getfiobyfd(pu, fd);					\
344 	if (fio == NULL) {						\
345 		errno = EINVAL;						\
346 		return -1;						\
347 	}								\
348 	if (fio->stat & FIO_WRGONE) {					\
349 		errno = ESHUTDOWN;					\
350 		return -1;						\
351 	}								\
352 } while (/*CONSTCOND*/0)
353 
354 int
puffs_framev_enqueue_cc(struct puffs_cc * pcc,int fd,struct puffs_framebuf * pufbuf,int flags)355 puffs_framev_enqueue_cc(struct puffs_cc *pcc, int fd,
356 	struct puffs_framebuf *pufbuf, int flags)
357 {
358 	struct puffs_usermount *pu = pcc->pcc_pu;
359 	struct puffs_fctrl_io *fio;
360 
361 	/*
362 	 * Technically we shouldn't allow this if RDGONE, but it's
363 	 * difficult to trap write close without allowing writes.
364 	 * And besides, there's probably a disconnect sequence in
365 	 * the protocol, so unexpectedly getting a closed fd is
366 	 * most likely an error condition.
367 	 */
368 	GETFIO(fd);
369 
370 	pufbuf->pcc = pcc;
371 	pufbuf->fcb = NULL;
372 	pufbuf->fcb_arg = NULL;
373 
374 	pufbuf->offset = 0;
375 	pufbuf->istat |= ISTAT_NODESTROY;
376 
377 	if (flags & PUFFS_FBQUEUE_URGENT)
378 		TAILQ_INSERT_HEAD(&fio->snd_qing, pufbuf, pfb_entries);
379 	else
380 		TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);
381 
382 	puffs_cc_yield(pcc);
383 	if (pufbuf->rv) {
384 		pufbuf->istat &= ~ISTAT_NODESTROY;
385 		errno = pufbuf->rv;
386 		return -1;
387 	}
388 
389 	return 0;
390 }
391 
392 int
puffs_framev_enqueue_cb(struct puffs_usermount * pu,int fd,struct puffs_framebuf * pufbuf,puffs_framev_cb fcb,void * arg,int flags)393 puffs_framev_enqueue_cb(struct puffs_usermount *pu, int fd,
394 	struct puffs_framebuf *pufbuf, puffs_framev_cb fcb, void *arg,
395 	int flags)
396 {
397 	struct puffs_fctrl_io *fio;
398 
399 	/* see enqueue_cc */
400 	GETFIO(fd);
401 
402 	pufbuf->pcc = NULL;
403 	pufbuf->fcb = fcb;
404 	pufbuf->fcb_arg = arg;
405 
406 	pufbuf->offset = 0;
407 	pufbuf->istat |= ISTAT_NODESTROY;
408 
409 	if (flags & PUFFS_FBQUEUE_URGENT)
410 		TAILQ_INSERT_HEAD(&fio->snd_qing, pufbuf, pfb_entries);
411 	else
412 		TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);
413 
414 	return 0;
415 }
416 
417 int
puffs_framev_enqueue_justsend(struct puffs_usermount * pu,int fd,struct puffs_framebuf * pufbuf,int reply,int flags)418 puffs_framev_enqueue_justsend(struct puffs_usermount *pu, int fd,
419 	struct puffs_framebuf *pufbuf, int reply, int flags)
420 {
421 	struct puffs_fctrl_io *fio;
422 
423 	assert((pufbuf->istat & ISTAT_INTERNAL) == 0);
424 
425 	GETFIO(fd);
426 
427 	pufbuf->pcc = NULL;
428 	pufbuf->fcb = NULL;
429 	pufbuf->fcb_arg = NULL;
430 
431 	pufbuf->offset = 0;
432 	pufbuf->istat |= ISTAT_NODESTROY;
433 	if (!reply)
434 		pufbuf->istat |= ISTAT_NOREPLY;
435 
436 	if (flags & PUFFS_FBQUEUE_URGENT)
437 		TAILQ_INSERT_HEAD(&fio->snd_qing, pufbuf, pfb_entries);
438 	else
439 		TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);
440 
441 	return 0;
442 }
443 
444 /* ARGSUSED */
445 int
puffs_framev_enqueue_directreceive(struct puffs_cc * pcc,int fd,struct puffs_framebuf * pufbuf,int flags)446 puffs_framev_enqueue_directreceive(struct puffs_cc *pcc, int fd,
447 	struct puffs_framebuf *pufbuf, int flags /* used in the future */)
448 {
449 	struct puffs_usermount *pu = pcc->pcc_pu;
450 	struct puffs_fctrl_io *fio;
451 
452 	assert((pufbuf->istat & ISTAT_INTERNAL) == 0);
453 
454 	fio = getfiobyfd(pu, fd);
455 	if (fio == NULL) {
456 		errno = EINVAL;
457 		return -1;
458 	}
459 
460 	/* XXX: should have cur_in queue */
461 	assert(fio->cur_in == NULL);
462 	fio->cur_in = pufbuf;
463 
464 	pufbuf->pcc = pcc;
465 	pufbuf->fcb = NULL;
466 	pufbuf->fcb_arg = NULL;
467 
468 	pufbuf->offset = 0;
469 	pufbuf->istat |= ISTAT_NODESTROY | ISTAT_DIRECT;
470 
471 	puffs_cc_yield(pcc);
472 	pufbuf->istat &= ~ISTAT_NODESTROY; /* XXX: not the right place */
473 	if (pufbuf->rv) {
474 		errno = pufbuf->rv;
475 		return -1;
476 	}
477 
478 	return 0;
479 }
480 
481 int
puffs_framev_enqueue_directsend(struct puffs_cc * pcc,int fd,struct puffs_framebuf * pufbuf,int flags)482 puffs_framev_enqueue_directsend(struct puffs_cc *pcc, int fd,
483 	struct puffs_framebuf *pufbuf, int flags)
484 {
485 	struct puffs_usermount *pu = pcc->pcc_pu;
486 	struct puffs_fctrl_io *fio;
487 
488 	assert((pufbuf->istat & ISTAT_INTERNAL) == 0);
489 
490 	if (flags & PUFFS_FBQUEUE_URGENT)
491 		abort(); /* EOPNOTSUPP for now */
492 
493 	GETFIO(fd);
494 
495 	pufbuf->pcc = pcc;
496 	pufbuf->fcb = NULL;
497 	pufbuf->fcb_arg = NULL;
498 
499 	pufbuf->offset = 0;
500 	pufbuf->istat |= ISTAT_NODESTROY | ISTAT_DIRECT;
501 
502 	TAILQ_INSERT_TAIL(&fio->snd_qing, pufbuf, pfb_entries);
503 
504 	puffs_cc_yield(pcc);
505 	if (pufbuf->rv) {
506 		pufbuf->istat &= ~ISTAT_NODESTROY;
507 		errno = pufbuf->rv;
508 		return -1;
509 	}
510 
511 	return 0;
512 }
513 
514 int
puffs_framev_framebuf_ccpromote(struct puffs_framebuf * pufbuf,struct puffs_cc * pcc)515 puffs_framev_framebuf_ccpromote(struct puffs_framebuf *pufbuf,
516 	struct puffs_cc *pcc)
517 {
518 
519 	if ((pufbuf->istat & ISTAT_ONQUEUE) == 0) {
520 		errno = EBUSY;
521 		return -1;
522 	}
523 
524 	pufbuf->pcc = pcc;
525 	pufbuf->fcb = NULL;
526 	pufbuf->fcb_arg = NULL;
527 	pufbuf->istat &= ~ISTAT_NOREPLY;
528 
529 	puffs_cc_yield(pcc);
530 
531 	return 0;
532 }
533 
534 int
puffs_framev_enqueue_waitevent(struct puffs_cc * pcc,int fd,int * what)535 puffs_framev_enqueue_waitevent(struct puffs_cc *pcc, int fd, int *what)
536 {
537 	struct puffs_usermount *pu = pcc->pcc_pu;
538 	struct puffs_fctrl_io *fio;
539 	struct puffs_fbevent feb;
540 	struct kevent kev;
541 	int rv, svwhat;
542 
543 	svwhat = *what;
544 
545 	if (*what == 0) {
546 		errno = EINVAL;
547 		return -1;
548 	}
549 
550 	fio = getfiobyfd(pu, fd);
551 	if (fio == NULL) {
552 		errno = EINVAL;
553 		return -1;
554 	}
555 
556 	feb.pcc = pcc;
557 	feb.what = *what & (PUFFS_FBIO_READ|PUFFS_FBIO_WRITE|PUFFS_FBIO_ERROR);
558 
559 	if (*what & PUFFS_FBIO_READ)
560 		if ((fio->stat & FIO_ENABLE_R) == 0)
561 			EV_SET(&kev, fd, EVFILT_READ, EV_ENABLE,
562 			    0, 0, (uintptr_t)fio);
563 
564 	if (kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL) == -1)
565 		return -1;
566 
567 	if (*what & PUFFS_FBIO_READ)
568 		fio->rwait++;
569 	if (*what & PUFFS_FBIO_WRITE)
570 		fio->wwait++;
571 
572 	LIST_INSERT_HEAD(&fio->ev_qing, &feb, pfe_entries);
573 	puffs_cc_yield(pcc);
574 
575 	assert(svwhat == *what);
576 
577 	if (*what & PUFFS_FBIO_READ) {
578 		fio->rwait--;
579 		if (fio->rwait == 0 && (fio->stat & FIO_ENABLE_R) == 0) {
580 			EV_SET(&kev, fd, EVFILT_READ, EV_DISABLE,
581 			    0, 0, (uintptr_t)fio);
582 			rv = kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL);
583 #if 0
584 			if (rv != 0)
585 				/* XXXXX oh dear */;
586 #endif
587 		}
588 	}
589 	if (*what & PUFFS_FBIO_WRITE)
590 		fio->wwait--;
591 
592 	if (feb.rv == 0) {
593 		*what = feb.what;
594 		rv = 0;
595 	} else {
596 		*what = PUFFS_FBIO_ERROR;
597 		errno = feb.rv;
598 		rv = -1;
599 	}
600 
601 	return rv;
602 }
603 
604 void
puffs__framev_notify(struct puffs_fctrl_io * fio,int what)605 puffs__framev_notify(struct puffs_fctrl_io *fio, int what)
606 {
607 	struct puffs_fbevent *fbevp;
608 
609  restart:
610 	LIST_FOREACH(fbevp, &fio->ev_qing, pfe_entries) {
611 		if (fbevp->what & what) {
612 			fbevp->what = what;
613 			fbevp->rv = 0;
614 			LIST_REMOVE(fbevp, pfe_entries);
615 			puffs_cc_continue(fbevp->pcc);
616 			goto restart;
617 		}
618 	}
619 }
620 
621 static struct puffs_framebuf *
findbuf(struct puffs_usermount * pu,struct puffs_framectrl * fctrl,struct puffs_fctrl_io * fio,struct puffs_framebuf * findme)622 findbuf(struct puffs_usermount *pu, struct puffs_framectrl *fctrl,
623 	struct puffs_fctrl_io *fio, struct puffs_framebuf *findme)
624 {
625 	struct puffs_framebuf *cand;
626 	int notresp = 0;
627 
628 	TAILQ_FOREACH(cand, &fio->res_qing, pfb_entries)
629 		if (fctrl->cmpfb(pu, findme, cand, &notresp) == 0 || notresp)
630 			break;
631 
632 	assert(!(notresp && cand == NULL));
633 	if (notresp || cand == NULL)
634 		return NULL;
635 
636 	TAILQ_REMOVE(&fio->res_qing, cand, pfb_entries);
637 	return cand;
638 }
639 
640 void
puffs__framebuf_moveinfo(struct puffs_framebuf * from,struct puffs_framebuf * to)641 puffs__framebuf_moveinfo(struct puffs_framebuf *from, struct puffs_framebuf *to)
642 {
643 
644 	assert(from->istat & ISTAT_INTERNAL);
645 
646 	/* migrate buffer */
647 	free(to->buf);
648 	to->buf = from->buf;
649 
650 	/* migrate buffer info */
651 	to->len = from->len;
652 	to->offset = from->offset;
653 	to->maxoff = from->maxoff;
654 
655 	from->buf = NULL;
656 	from->len = 0;
657 }
658 
659 void
puffs__framev_input(struct puffs_usermount * pu,struct puffs_framectrl * fctrl,struct puffs_fctrl_io * fio)660 puffs__framev_input(struct puffs_usermount *pu, struct puffs_framectrl *fctrl,
661 	struct puffs_fctrl_io *fio)
662 {
663 	struct puffs_framebuf *pufbuf, *appbuf;
664 	int rv, complete;
665 
666 	while ((fio->stat & FIO_DEAD) == 0 && (fio->stat & FIO_ENABLE_R)) {
667 		if ((pufbuf = fio->cur_in) == NULL) {
668 			pufbuf = puffs_framebuf_make();
669 			if (pufbuf == NULL)
670 				return;
671 			pufbuf->istat |= ISTAT_INTERNAL;
672 			fio->cur_in = pufbuf;
673 		}
674 
675 		complete = 0;
676 		rv = fctrl->rfb(pu, pufbuf, fio->io_fd, &complete);
677 
678 		/* error */
679 		if (rv) {
680 			puffs__framev_readclose(pu, fio, rv);
681 			fio->cur_in = NULL;
682 			return;
683 		}
684 
685 		/* partial read, come back to fight another day */
686 		if (complete == 0)
687 			break;
688 
689 		/* else: full read, process */
690 		fio->cur_in = NULL;
691 		if ((pufbuf->istat & ISTAT_DIRECT) == 0) {
692 			appbuf = findbuf(pu, fctrl, fio, pufbuf);
693 
694 			/*
695 			 * No request for this frame?  If fs implements
696 			 * gotfb, give frame to that.  Otherwise drop it.
697 			 */
698 			if (appbuf == NULL) {
699 				if (fctrl->gotfb) {
700 					pufbuf->istat &= ~ISTAT_INTERNAL;
701 					fctrl->gotfb(pu, pufbuf);
702 				} else {
703 					puffs_framebuf_destroy(pufbuf);
704 				}
705 				continue;
706 			}
707 
708 			puffs__framebuf_moveinfo(pufbuf, appbuf);
709 			puffs_framebuf_destroy(pufbuf);
710 		} else {
711 			appbuf = pufbuf;
712 		}
713 		appbuf->istat &= ~ISTAT_NODESTROY;
714 
715 		if (appbuf->pcc) {
716 			puffs__cc_cont(appbuf->pcc);
717 		} else if (appbuf->fcb) {
718 			appbuf->fcb(pu, appbuf, appbuf->fcb_arg, 0);
719 		} else {
720 			puffs_framebuf_destroy(appbuf);
721 		}
722 
723 		/* hopeless romantics, here we go again */
724 	}
725 }
726 
727 int
puffs__framev_output(struct puffs_usermount * pu,struct puffs_framectrl * fctrl,struct puffs_fctrl_io * fio)728 puffs__framev_output(struct puffs_usermount *pu, struct puffs_framectrl *fctrl,
729 	struct puffs_fctrl_io *fio)
730 {
731 	struct puffs_framebuf *pufbuf;
732 	int rv, complete, done;
733 
734 	if (fio->stat & FIO_DEAD)
735 		return 0;
736 
737 	for (pufbuf = TAILQ_FIRST(&fio->snd_qing), done = 0;
738 	    pufbuf && (fio->stat & FIO_DEAD) == 0 && fio->stat & FIO_ENABLE_W;
739 	    pufbuf = TAILQ_FIRST(&fio->snd_qing)) {
740 		complete = 0;
741 		rv = fctrl->wfb(pu, pufbuf, fio->io_fd, &complete);
742 
743 		if (rv) {
744 			puffs__framev_writeclose(pu, fio, rv);
745 			done = 1;
746 			break;
747 		}
748 
749 		/* partial write */
750 		if (complete == 0)
751 			return done;
752 
753 		/* else, complete write */
754 		TAILQ_REMOVE(&fio->snd_qing, pufbuf, pfb_entries);
755 
756 		/* can't wait for result if we can't read */
757 		if (fio->stat & FIO_RDGONE) {
758 			errnotify(pu, pufbuf, ENXIO);
759 			done = 1;
760 		} else if ((pufbuf->istat & ISTAT_DIRECT)) {
761 			pufbuf->istat &= ~ISTAT_NODESTROY;
762 			done = 1;
763 			puffs__cc_cont(pufbuf->pcc);
764 		} else if ((pufbuf->istat & ISTAT_NOREPLY) == 0) {
765 			TAILQ_INSERT_TAIL(&fio->res_qing, pufbuf,
766 			    pfb_entries);
767 		} else {
768 			pufbuf->istat &= ~ISTAT_NODESTROY;
769 			puffs_framebuf_destroy(pufbuf);
770 		}
771 
772 		/* omstart! */
773 	}
774 
775 	return done;
776 }
777 
778 int
puffs__framev_addfd_ctrl(struct puffs_usermount * pu,int fd,int what,struct puffs_framectrl * pfctrl)779 puffs__framev_addfd_ctrl(struct puffs_usermount *pu, int fd, int what,
780 	struct puffs_framectrl *pfctrl)
781 {
782 	struct puffs_fctrl_io *fio;
783 	struct kevent *newevs;
784 	struct kevent kev[2];
785 	size_t nevs;
786 	int rv, readenable;
787 
788 	nevs = pu->pu_nevs+2;
789 	newevs = realloc(pu->pu_evs, nevs*sizeof(struct kevent));
790 	if (newevs == NULL)
791 		return -1;
792 	pu->pu_evs = newevs;
793 
794 	fio = malloc(sizeof(struct puffs_fctrl_io));
795 	if (fio == NULL)
796 		return -1;
797 	memset(fio, 0, sizeof(struct puffs_fctrl_io));
798 	fio->io_fd = fd;
799 	fio->cur_in = NULL;
800 	fio->fctrl = pfctrl;
801 	TAILQ_INIT(&fio->snd_qing);
802 	TAILQ_INIT(&fio->res_qing);
803 	LIST_INIT(&fio->ev_qing);
804 
805 	readenable = 0;
806 	if ((what & PUFFS_FBIO_READ) == 0)
807 		readenable = EV_DISABLE;
808 
809 	if (pu->pu_state & PU_INLOOP) {
810 		EV_SET(&kev[0], fd, EVFILT_READ,
811 		    EV_ADD|readenable, 0, 0, (intptr_t)fio);
812 		EV_SET(&kev[1], fd, EVFILT_WRITE,
813 		    EV_ADD|EV_DISABLE, 0, 0, (intptr_t)fio);
814 		rv = kevent(pu->pu_kq, kev, 2, NULL, 0, NULL);
815 		if (rv == -1) {
816 			free(fio);
817 			return -1;
818 		}
819 	}
820 	if (what & PUFFS_FBIO_READ)
821 		fio->stat |= FIO_ENABLE_R;
822 	if (what & PUFFS_FBIO_WRITE)
823 		fio->stat |= FIO_ENABLE_W;
824 
825 	LIST_INSERT_HEAD(&pu->pu_ios, fio, fio_entries);
826 	pu->pu_nevs = nevs;
827 
828 	return 0;
829 }
830 
831 int
puffs_framev_addfd(struct puffs_usermount * pu,int fd,int what)832 puffs_framev_addfd(struct puffs_usermount *pu, int fd, int what)
833 {
834 
835 	return puffs__framev_addfd_ctrl(pu, fd, what,
836 	    &pu->pu_framectrl[PU_FRAMECTRL_USER]);
837 }
838 
839 /*
840  * XXX: the following en/disable should be coalesced and executed
841  * only during the actual kevent call.  So feel free to fix if
842  * threatened by mindblowing boredom.
843  */
844 
845 int
puffs_framev_enablefd(struct puffs_usermount * pu,int fd,int what)846 puffs_framev_enablefd(struct puffs_usermount *pu, int fd, int what)
847 {
848 	struct kevent kev;
849 	struct puffs_fctrl_io *fio;
850 	int rv = 0;
851 
852 	assert((what & (PUFFS_FBIO_READ | PUFFS_FBIO_WRITE)) != 0);
853 
854 	fio = getfiobyfd(pu, fd);
855 	if (fio == NULL) {
856 		errno = ENXIO;
857 		return -1;
858 	}
859 
860 	/* write is enabled in the event loop if there is output */
861 	if (what & PUFFS_FBIO_READ && fio->rwait == 0) {
862 		EV_SET(&kev, fd, EVFILT_READ, EV_ENABLE, 0, 0, (uintptr_t)fio);
863 		rv = kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL);
864 	}
865 
866 	if (rv == 0) {
867 		if (what & PUFFS_FBIO_READ)
868 			fio->stat |= FIO_ENABLE_R;
869 		if (what & PUFFS_FBIO_WRITE)
870 			fio->stat |= FIO_ENABLE_W;
871 	}
872 
873 	return rv;
874 }
875 
876 int
puffs_framev_disablefd(struct puffs_usermount * pu,int fd,int what)877 puffs_framev_disablefd(struct puffs_usermount *pu, int fd, int what)
878 {
879 	struct kevent kev[2];
880 	struct puffs_fctrl_io *fio;
881 	size_t i;
882 	int rv;
883 
884 	assert((what & (PUFFS_FBIO_READ | PUFFS_FBIO_WRITE)) != 0);
885 
886 	fio = getfiobyfd(pu, fd);
887 	if (fio == NULL) {
888 		errno = ENXIO;
889 		return -1;
890 	}
891 
892 	i = 0;
893 	if (what & PUFFS_FBIO_READ && fio->rwait == 0) {
894 		EV_SET(&kev[0], fd,
895 		    EVFILT_READ, EV_DISABLE, 0, 0, (uintptr_t)fio);
896 		i++;
897 	}
898 	if (what & PUFFS_FBIO_WRITE && fio->stat & FIO_WR && fio->wwait == 0) {
899 		EV_SET(&kev[1], fd,
900 		    EVFILT_WRITE, EV_DISABLE, 0, 0, (uintptr_t)fio);
901 		i++;
902 	}
903 	if (i)
904 		rv = kevent(pu->pu_kq, kev, i, NULL, 0, NULL);
905 	else
906 		rv = 0;
907 
908 	if (rv == 0) {
909 		if (what & PUFFS_FBIO_READ)
910 			fio->stat &= ~FIO_ENABLE_R;
911 		if (what & PUFFS_FBIO_WRITE)
912 			fio->stat &= ~FIO_ENABLE_W;
913 	}
914 
915 	return rv;
916 }
917 
918 void
puffs__framev_readclose(struct puffs_usermount * pu,struct puffs_fctrl_io * fio,int error)919 puffs__framev_readclose(struct puffs_usermount *pu,
920 	struct puffs_fctrl_io *fio, int error)
921 {
922 	struct puffs_framebuf *pufbuf;
923 	struct kevent kev;
924 	int notflag;
925 
926 	if (fio->stat & FIO_RDGONE || fio->stat & FIO_DEAD)
927 		return;
928 	fio->stat |= FIO_RDGONE;
929 
930 	if (fio->cur_in) {
931 		if ((fio->cur_in->istat & ISTAT_DIRECT) == 0) {
932 			puffs_framebuf_destroy(fio->cur_in);
933 			fio->cur_in = NULL;
934 		} else {
935 			errnotify(pu, fio->cur_in, error);
936 		}
937 	}
938 
939 	while ((pufbuf = TAILQ_FIRST(&fio->res_qing)) != NULL) {
940 		TAILQ_REMOVE(&fio->res_qing, pufbuf, pfb_entries);
941 		errnotify(pu, pufbuf, error);
942 	}
943 
944 	EV_SET(&kev, fio->io_fd, EVFILT_READ, EV_DELETE, 0, 0, 0);
945 	(void) kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL);
946 
947 	notflag = PUFFS_FBIO_READ;
948 	if (fio->stat & FIO_WRGONE)
949 		notflag |= PUFFS_FBIO_WRITE;
950 
951 	if (fio->fctrl->fdnotfn)
952 		fio->fctrl->fdnotfn(pu, fio->io_fd, notflag);
953 }
954 
955 void
puffs__framev_writeclose(struct puffs_usermount * pu,struct puffs_fctrl_io * fio,int error)956 puffs__framev_writeclose(struct puffs_usermount *pu,
957 	struct puffs_fctrl_io *fio, int error)
958 {
959 	struct puffs_framebuf *pufbuf;
960 	struct kevent kev;
961 	int notflag;
962 
963 	if (fio->stat & FIO_WRGONE || fio->stat & FIO_DEAD)
964 		return;
965 	fio->stat |= FIO_WRGONE;
966 
967 	while ((pufbuf = TAILQ_FIRST(&fio->snd_qing)) != NULL) {
968 		TAILQ_REMOVE(&fio->snd_qing, pufbuf, pfb_entries);
969 		errnotify(pu, pufbuf, error);
970 	}
971 
972 	EV_SET(&kev, fio->io_fd, EVFILT_WRITE, EV_DELETE, 0, 0, 0);
973 	(void) kevent(pu->pu_kq, &kev, 1, NULL, 0, NULL);
974 
975 	notflag = PUFFS_FBIO_WRITE;
976 	if (fio->stat & FIO_RDGONE)
977 		notflag |= PUFFS_FBIO_READ;
978 
979 	if (fio->fctrl->fdnotfn)
980 		fio->fctrl->fdnotfn(pu, fio->io_fd, notflag);
981 }
982 
983 static int
removefio(struct puffs_usermount * pu,struct puffs_fctrl_io * fio,int error)984 removefio(struct puffs_usermount *pu, struct puffs_fctrl_io *fio, int error)
985 {
986 	struct puffs_fbevent *fbevp;
987 
988 	LIST_REMOVE(fio, fio_entries);
989 	if (pu->pu_state & PU_INLOOP) {
990 		puffs__framev_readclose(pu, fio, error);
991 		puffs__framev_writeclose(pu, fio, error);
992 	}
993 
994 	while ((fbevp = LIST_FIRST(&fio->ev_qing)) != NULL) {
995 		fbevp->rv = error;
996 		LIST_REMOVE(fbevp, pfe_entries);
997 		puffs__goto(fbevp->pcc);
998 	}
999 
1000 	/* don't bother with realloc */
1001 	pu->pu_nevs -= 2;
1002 
1003 	/* don't free us yet, might have some references in event arrays */
1004 	fio->stat |= FIO_DEAD;
1005 	LIST_INSERT_HEAD(&pu->pu_ios_rmlist, fio, fio_entries);
1006 
1007 	return 0;
1008 
1009 }
1010 
1011 int
puffs_framev_removefd(struct puffs_usermount * pu,int fd,int error)1012 puffs_framev_removefd(struct puffs_usermount *pu, int fd, int error)
1013 {
1014 	struct puffs_fctrl_io *fio;
1015 
1016 	fio = getfiobyfd(pu, fd);
1017 	if (fio == NULL) {
1018 		errno = ENXIO;
1019 		return -1;
1020 	}
1021 
1022 	return removefio(pu, fio, error ? error : ECONNRESET);
1023 }
1024 
1025 void
puffs_framev_removeonclose(struct puffs_usermount * pu,int fd,int what)1026 puffs_framev_removeonclose(struct puffs_usermount *pu, int fd, int what)
1027 {
1028 
1029 	if (what == (PUFFS_FBIO_READ | PUFFS_FBIO_WRITE))
1030 		(void) puffs_framev_removefd(pu, fd, ECONNRESET);
1031 }
1032 
1033 void
puffs_framev_unmountonclose(struct puffs_usermount * pu,int fd,int what)1034 puffs_framev_unmountonclose(struct puffs_usermount *pu, int fd, int what)
1035 {
1036 
1037 	/* XXX & X: unmount is non-sensible */
1038 	puffs_framev_removeonclose(pu, fd, what);
1039 	if (what == (PUFFS_FBIO_READ | PUFFS_FBIO_WRITE))
1040 		PU_SETSTATE(pu, PUFFS_STATE_UNMOUNTED);
1041 }
1042 
1043 void
puffs_framev_init(struct puffs_usermount * pu,puffs_framev_readframe_fn rfb,puffs_framev_writeframe_fn wfb,puffs_framev_cmpframe_fn cmpfb,puffs_framev_gotframe_fn gotfb,puffs_framev_fdnotify_fn fdnotfn)1044 puffs_framev_init(struct puffs_usermount *pu,
1045 	puffs_framev_readframe_fn rfb, puffs_framev_writeframe_fn wfb,
1046 	puffs_framev_cmpframe_fn cmpfb, puffs_framev_gotframe_fn gotfb,
1047 	puffs_framev_fdnotify_fn fdnotfn)
1048 {
1049 	struct puffs_framectrl *pfctrl;
1050 
1051 	pfctrl = &pu->pu_framectrl[PU_FRAMECTRL_USER];
1052 	pfctrl->rfb = rfb;
1053 	pfctrl->wfb = wfb;
1054 	pfctrl->cmpfb = cmpfb;
1055 	pfctrl->gotfb = gotfb;
1056 	pfctrl->fdnotfn = fdnotfn;
1057 }
1058 
1059 void
puffs__framev_exit(struct puffs_usermount * pu)1060 puffs__framev_exit(struct puffs_usermount *pu)
1061 {
1062 	struct puffs_fctrl_io *fio;
1063 
1064 	while ((fio = LIST_FIRST(&pu->pu_ios)) != NULL)
1065 		removefio(pu, fio, ENXIO);
1066 	free(pu->pu_evs);
1067 
1068 	/* closing pu->pu_kq takes care of puffsfd */
1069 }
1070