1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2002 Poul-Henning Kamp
5 * Copyright (c) 2002 Networks Associates Technology, Inc.
6 * All rights reserved.
7 *
8 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
9 * and NAI Labs, the Security Research Division of Network Associates, Inc.
10 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
11 * DARPA CHATS research program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 * 3. The names of the authors may not be used to endorse or promote
22 *    products derived from this software without specific prior written
23 *    permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/kernel.h>
44#include <sys/malloc.h>
45#include <sys/bio.h>
46#include <sys/sysctl.h>
47#include <sys/proc.h>
48#include <sys/lock.h>
49#include <sys/mutex.h>
50#include <sys/errno.h>
51#include <sys/sbuf.h>
52#include <geom/geom.h>
53#include <geom/geom_slice.h>
54#include <machine/stdarg.h>
55
56static g_access_t g_slice_access;
57static g_start_t g_slice_start;
58
59static struct g_slicer *
60g_slice_alloc(unsigned nslice, unsigned scsize)
61{
62	struct g_slicer *gsp;
63
64	gsp = g_malloc(sizeof *gsp, M_WAITOK | M_ZERO);
65	if (scsize > 0)
66		gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO);
67	else
68		gsp->softc = NULL;
69	gsp->slices = g_malloc(nslice * sizeof(struct g_slice),
70	    M_WAITOK | M_ZERO);
71	gsp->nslice = nslice;
72	return (gsp);
73}
74
75static void
76g_slice_free(struct g_geom *gp)
77{
78	struct g_slicer *gsp;
79
80	gsp = gp->softc;
81	gp->softc = NULL;
82
83	/*
84	 * We can get multiple spoiled events before wither-washer
85	 * detaches our consumer, so this can get called multiple
86	 * times.
87	 */
88	if (gsp == NULL)
89		return;
90	g_free(gsp->slices);
91	if (gsp->hotspot != NULL)
92		g_free(gsp->hotspot);
93	if (gsp->softc != NULL)
94		g_free(gsp->softc);
95	g_free(gsp);
96}
97
98static int
99g_slice_access(struct g_provider *pp, int dr, int dw, int de)
100{
101	int error;
102	u_int u;
103	struct g_geom *gp;
104	struct g_consumer *cp;
105	struct g_provider *pp2;
106	struct g_slicer *gsp;
107	struct g_slice *gsl, *gsl2;
108
109	gp = pp->geom;
110	cp = LIST_FIRST(&gp->consumer);
111	KASSERT (cp != NULL, ("g_slice_access but no consumer"));
112	gsp = gp->softc;
113	if (dr > 0 || dw > 0 || de > 0) {
114		gsl = &gsp->slices[pp->index];
115		for (u = 0; u < gsp->nslice; u++) {
116			gsl2 = &gsp->slices[u];
117			if (gsl2->length == 0)
118				continue;
119			if (u == pp->index)
120				continue;
121			if (gsl->offset + gsl->length <= gsl2->offset)
122				continue;
123			if (gsl2->offset + gsl2->length <= gsl->offset)
124				continue;
125			/* overlap */
126			pp2 = gsl2->provider;
127			if ((pp->acw + dw) > 0 && pp2->ace > 0)
128				return (EPERM);
129			if ((pp->ace + de) > 0 && pp2->acw > 0)
130				return (EPERM);
131		}
132	}
133	/* On first open, grab an extra "exclusive" bit */
134	if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
135		de++;
136	/* ... and let go of it on last close */
137	if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1)
138		de--;
139	error = g_access(cp, dr, dw, de);
140
141	/*
142	 * Free the softc if all providers have been closed and this geom
143	 * is being removed.
144	 */
145	if (error == 0 && (gp->flags & G_GEOM_WITHER) != 0 &&
146	    (cp->acr + cp->acw + cp->ace) == 0)
147		g_slice_free(gp);
148
149	return (error);
150}
151
152/*
153 * XXX: It should be possible to specify here if we should finish all of the
154 * XXX: bio, or only the non-hot bits.  This would get messy if there were
155 * XXX: two hot spots in the same bio, so for now we simply finish off the
156 * XXX: entire bio.  Modifying hot data on the way to disk is frowned on
157 * XXX: so making that considerably harder is not a bad idea anyway.
158 */
159void
160g_slice_finish_hot(struct bio *bp)
161{
162	struct bio *bp2;
163	struct g_geom *gp;
164	struct g_consumer *cp;
165	struct g_slicer *gsp;
166	struct g_slice *gsl;
167	int idx;
168
169	KASSERT(bp->bio_to != NULL,
170	    ("NULL bio_to in g_slice_finish_hot(%p)", bp));
171	KASSERT(bp->bio_from != NULL,
172	    ("NULL bio_from in g_slice_finish_hot(%p)", bp));
173	gp = bp->bio_to->geom;
174	gsp = gp->softc;
175	cp = LIST_FIRST(&gp->consumer);
176	KASSERT(cp != NULL, ("NULL consumer in g_slice_finish_hot(%p)", bp));
177	idx = bp->bio_to->index;
178	gsl = &gsp->slices[idx];
179
180	bp2 = g_clone_bio(bp);
181	if (bp2 == NULL) {
182		g_io_deliver(bp, ENOMEM);
183		return;
184	}
185	if (bp2->bio_offset + bp2->bio_length > gsl->length)
186		bp2->bio_length = gsl->length - bp2->bio_offset;
187	bp2->bio_done = g_std_done;
188	bp2->bio_offset += gsl->offset;
189	g_io_request(bp2, cp);
190	return;
191}
192
193static void
194g_slice_done(struct bio *bp)
195{
196
197	KASSERT(bp->bio_cmd == BIO_GETATTR &&
198	    strcmp(bp->bio_attribute, "GEOM::ident") == 0,
199	    ("bio_cmd=0x%x bio_attribute=%s", bp->bio_cmd, bp->bio_attribute));
200
201	if (bp->bio_error == 0 && bp->bio_data[0] != '\0') {
202		char idx[8];
203
204		/* Add index to the ident received. */
205		snprintf(idx, sizeof(idx), "s%d",
206		    bp->bio_parent->bio_to->index);
207		if (strlcat(bp->bio_data, idx, bp->bio_length) >=
208		    bp->bio_length) {
209			bp->bio_error = EFAULT;
210		}
211	}
212	g_std_done(bp);
213}
214
215static void
216g_slice_start(struct bio *bp)
217{
218	struct bio *bp2;
219	struct g_provider *pp;
220	struct g_geom *gp;
221	struct g_consumer *cp;
222	struct g_slicer *gsp;
223	struct g_slice *gsl;
224	struct g_slice_hot *ghp;
225	int idx, error;
226	u_int m_index;
227	off_t t;
228
229	pp = bp->bio_to;
230	gp = pp->geom;
231	gsp = gp->softc;
232	cp = LIST_FIRST(&gp->consumer);
233	idx = pp->index;
234	gsl = &gsp->slices[idx];
235	switch(bp->bio_cmd) {
236	case BIO_READ:
237	case BIO_WRITE:
238	case BIO_DELETE:
239		if (bp->bio_offset > gsl->length) {
240			g_io_deliver(bp, EINVAL); /* XXX: EWHAT ? */
241			return;
242		}
243		/*
244		 * Check if we collide with any hot spaces, and call the
245		 * method once if so.
246		 */
247		t = bp->bio_offset + gsl->offset;
248		for (m_index = 0; m_index < gsp->nhotspot; m_index++) {
249			ghp = &gsp->hotspot[m_index];
250			if (t >= ghp->offset + ghp->length)
251				continue;
252			if (t + bp->bio_length <= ghp->offset)
253				continue;
254			switch(bp->bio_cmd) {
255			case BIO_READ:		idx = ghp->ract; break;
256			case BIO_WRITE:		idx = ghp->wact; break;
257			case BIO_DELETE:	idx = ghp->dact; break;
258			}
259			switch(idx) {
260			case G_SLICE_HOT_ALLOW:
261				/* Fall out and continue normal processing */
262				continue;
263			case G_SLICE_HOT_DENY:
264				g_io_deliver(bp, EROFS);
265				return;
266			case G_SLICE_HOT_START:
267				error = gsp->start(bp);
268				if (error && error != EJUSTRETURN)
269					g_io_deliver(bp, error);
270				return;
271			case G_SLICE_HOT_CALL:
272				error = g_post_event(gsp->hot, bp, M_NOWAIT,
273				    gp, NULL);
274				if (error)
275					g_io_deliver(bp, error);
276				return;
277			}
278			break;
279		}
280		bp2 = g_clone_bio(bp);
281		if (bp2 == NULL) {
282			g_io_deliver(bp, ENOMEM);
283			return;
284		}
285		if (bp2->bio_offset + bp2->bio_length > gsl->length)
286			bp2->bio_length = gsl->length - bp2->bio_offset;
287		bp2->bio_done = g_std_done;
288		bp2->bio_offset += gsl->offset;
289		g_io_request(bp2, cp);
290		return;
291	case BIO_GETATTR:
292		/* Give the real method a chance to override */
293		if (gsp->start != NULL && gsp->start(bp))
294			return;
295		if (!strcmp("GEOM::ident", bp->bio_attribute)) {
296			bp2 = g_clone_bio(bp);
297			if (bp2 == NULL) {
298				g_io_deliver(bp, ENOMEM);
299				return;
300			}
301			bp2->bio_done = g_slice_done;
302			g_io_request(bp2, cp);
303			return;
304		}
305		if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) {
306			struct g_kerneldump *gkd;
307
308			gkd = (struct g_kerneldump *)bp->bio_data;
309			gkd->offset += gsp->slices[idx].offset;
310			if (gkd->length > gsp->slices[idx].length)
311				gkd->length = gsp->slices[idx].length;
312			/* now, pass it on downwards... */
313		}
314		/* FALLTHROUGH */
315	case BIO_FLUSH:
316		bp2 = g_clone_bio(bp);
317		if (bp2 == NULL) {
318			g_io_deliver(bp, ENOMEM);
319			return;
320		}
321		bp2->bio_done = g_std_done;
322		g_io_request(bp2, cp);
323		break;
324	default:
325		g_io_deliver(bp, EOPNOTSUPP);
326		return;
327	}
328}
329
330void
331g_slice_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
332{
333	struct g_slicer *gsp;
334
335	gsp = gp->softc;
336	if (indent == NULL) {
337		sbuf_printf(sb, " i %u", pp->index);
338		sbuf_printf(sb, " o %ju",
339		    (uintmax_t)gsp->slices[pp->index].offset);
340		return;
341	}
342	if (pp != NULL) {
343		sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index);
344		sbuf_printf(sb, "%s<length>%ju</length>\n",
345		    indent, (uintmax_t)gsp->slices[pp->index].length);
346		sbuf_printf(sb, "%s<seclength>%ju</seclength>\n", indent,
347		    (uintmax_t)gsp->slices[pp->index].length / 512);
348		sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent,
349		    (uintmax_t)gsp->slices[pp->index].offset);
350		sbuf_printf(sb, "%s<secoffset>%ju</secoffset>\n", indent,
351		    (uintmax_t)gsp->slices[pp->index].offset / 512);
352	}
353}
354
355int
356g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...)
357{
358	struct g_provider *pp, *pp2;
359	struct g_slicer *gsp;
360	struct g_slice *gsl;
361	va_list ap;
362	struct sbuf *sb;
363	int acc;
364
365	g_trace(G_T_TOPOLOGY, "g_slice_config(%s, %d, %d)",
366	     gp->name, idx, how);
367	g_topology_assert();
368	gsp = gp->softc;
369	if (idx >= gsp->nslice)
370		return(EINVAL);
371	gsl = &gsp->slices[idx];
372	pp = gsl->provider;
373	if (pp != NULL)
374		acc = pp->acr + pp->acw + pp->ace;
375	else
376		acc = 0;
377	if (acc != 0 && how != G_SLICE_CONFIG_FORCE) {
378		if (length < gsl->length)
379			return(EBUSY);
380		if (offset != gsl->offset)
381			return(EBUSY);
382	}
383	/* XXX: check offset + length <= MEDIASIZE */
384	if (how == G_SLICE_CONFIG_CHECK)
385		return (0);
386	gsl->length = length;
387	gsl->offset = offset;
388	gsl->sectorsize = sectorsize;
389	if (length == 0) {
390		if (pp == NULL)
391			return (0);
392		if (bootverbose)
393			printf("GEOM: Deconfigure %s\n", pp->name);
394		g_wither_provider(pp, ENXIO);
395		gsl->provider = NULL;
396		gsp->nprovider--;
397		return (0);
398	}
399	if (pp != NULL) {
400		if (bootverbose)
401			printf("GEOM: Reconfigure %s, start %jd length %jd end %jd\n",
402			    pp->name, (intmax_t)offset, (intmax_t)length,
403			    (intmax_t)(offset + length - 1));
404		g_resize_provider(pp, gsl->length);
405		return (0);
406	}
407	sb = sbuf_new_auto();
408	va_start(ap, fmt);
409	sbuf_vprintf(sb, fmt, ap);
410	va_end(ap);
411	sbuf_finish(sb);
412	pp = g_new_providerf(gp, "%s", sbuf_data(sb));
413	pp2 = LIST_FIRST(&gp->consumer)->provider;
414	pp->stripesize = pp2->stripesize;
415	pp->stripeoffset = pp2->stripeoffset + offset;
416	if (pp->stripesize > 0)
417		pp->stripeoffset %= pp->stripesize;
418	if (gsp->nhotspot == 0) {
419		pp->flags |= pp2->flags & G_PF_ACCEPT_UNMAPPED;
420		pp->flags |= G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE;
421	}
422	if (0 && bootverbose)
423		printf("GEOM: Configure %s, start %jd length %jd end %jd\n",
424		    pp->name, (intmax_t)offset, (intmax_t)length,
425		    (intmax_t)(offset + length - 1));
426	pp->index = idx;
427	pp->mediasize = gsl->length;
428	pp->sectorsize = gsl->sectorsize;
429	gsl->provider = pp;
430	gsp->nprovider++;
431	g_error_provider(pp, 0);
432	sbuf_delete(sb);
433	return(0);
434}
435
436/*
437 * Configure "hotspots".  A hotspot is a piece of the parent device which
438 * this particular slicer cares about for some reason.  Typically because
439 * it contains meta-data used to configure the slicer.
440 * A hotspot is identified by its index number. The offset and length are
441 * relative to the parent device, and the three "?act" fields specify
442 * what action to take on BIO_READ, BIO_DELETE and BIO_WRITE.
443 *
444 * XXX: There may be a race relative to g_slice_start() here, if an existing
445 * XXX: hotspot is changed wile I/O is happening.  Should this become a problem
446 * XXX: we can protect the hotspot stuff with a mutex.
447 */
448
449int
450g_slice_conf_hot(struct g_geom *gp, u_int idx, off_t offset, off_t length, int ract, int dact, int wact)
451{
452	struct g_slicer *gsp;
453	struct g_slice_hot *gsl, *gsl2;
454	struct g_consumer *cp;
455	struct g_provider *pp;
456
457	g_trace(G_T_TOPOLOGY, "g_slice_conf_hot(%s, idx: %d, off: %jd, len: %jd)",
458	    gp->name, idx, (intmax_t)offset, (intmax_t)length);
459	g_topology_assert();
460	gsp = gp->softc;
461	/* Deny unmapped I/O and direct dispatch if hotspots are used. */
462	if (gsp->nhotspot == 0) {
463		LIST_FOREACH(pp, &gp->provider, provider)
464			pp->flags &= ~(G_PF_ACCEPT_UNMAPPED |
465			    G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE);
466		LIST_FOREACH(cp, &gp->consumer, consumer)
467			cp->flags &= ~(G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE);
468	}
469	gsl = gsp->hotspot;
470	if(idx >= gsp->nhotspot) {
471		gsl2 = g_malloc((idx + 1) * sizeof *gsl2, M_WAITOK | M_ZERO);
472		if (gsp->hotspot != NULL)
473			bcopy(gsp->hotspot, gsl2, gsp->nhotspot * sizeof *gsl2);
474		gsp->hotspot = gsl2;
475		if (gsp->hotspot != NULL)
476			g_free(gsl);
477		gsl = gsl2;
478		gsp->nhotspot = idx + 1;
479	}
480	gsl[idx].offset = offset;
481	gsl[idx].length = length;
482	KASSERT(!((ract | dact | wact) & G_SLICE_HOT_START)
483	    || gsp->start != NULL, ("G_SLICE_HOT_START but no slice->start"));
484	/* XXX: check that we _have_ a start function if HOT_START specified */
485	gsl[idx].ract = ract;
486	gsl[idx].dact = dact;
487	gsl[idx].wact = wact;
488	return (0);
489}
490
491void
492g_slice_orphan(struct g_consumer *cp)
493{
494	struct g_geom *gp;
495
496	g_topology_assert();
497	gp = cp->geom;
498	g_trace(G_T_TOPOLOGY, "%s(%p/%s)", __func__, cp, gp->name);
499	g_wither_geom(gp, ENXIO);
500
501	/*
502	 * We can safely free the softc now if there are no accesses,
503	 * otherwise g_slice_access() will do that after the last close.
504	 */
505	if ((cp->acr + cp->acw + cp->ace) == 0)
506		g_slice_free(gp);
507}
508
509void
510g_slice_spoiled(struct g_consumer *cp)
511{
512
513	g_trace(G_T_TOPOLOGY, "%s(%p/%s)", __func__, cp, cp->geom->name);
514	cp->flags |= G_CF_ORPHAN;
515	g_slice_orphan(cp);
516}
517
518int
519g_slice_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
520{
521
522	g_slice_spoiled(LIST_FIRST(&gp->consumer));
523	return (0);
524}
525
526struct g_geom *
527g_slice_new(struct g_class *mp, u_int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start)
528{
529	struct g_geom *gp;
530	struct g_slicer *gsp;
531	struct g_consumer *cp;
532	void **vp;
533	int error;
534
535	g_topology_assert();
536	vp = (void **)extrap;
537	gp = g_new_geomf(mp, "%s", pp->name);
538	gsp = g_slice_alloc(slices, extra);
539	gsp->start = start;
540	gp->softc = gsp;
541	gp->start = g_slice_start;
542	gp->access = g_slice_access;
543	gp->orphan = g_slice_orphan;
544	gp->spoiled = g_slice_spoiled;
545	if (gp->dumpconf == NULL)
546		gp->dumpconf = g_slice_dumpconf;
547	if (gp->class->destroy_geom == NULL)
548		gp->class->destroy_geom = g_slice_destroy_geom;
549	cp = g_new_consumer(gp);
550	cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
551	error = g_attach(cp, pp);
552	if (error == 0)
553		error = g_access(cp, 1, 0, 0);
554	if (error) {
555		g_wither_geom(gp, ENXIO);
556		return (NULL);
557	}
558	if (extrap != NULL)
559		*vp = gsp->softc;
560	*cpp = cp;
561	return (gp);
562}
563