geom_slice.c revision 107953
1/*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7 * and NAI Labs, the Security Research Division of Network Associates, Inc.
8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9 * DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote
20 *    products derived from this software without specific prior written
21 *    permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * $FreeBSD: head/sys/geom/geom_slice.c 107953 2002-12-16 22:33:27Z phk $
36 */
37
38
39#include <sys/param.h>
40#include <sys/stdint.h>
41#ifndef _KERNEL
42#include <stdio.h>
43#include <unistd.h>
44#include <stdlib.h>
45#include <signal.h>
46#include <string.h>
47#include <err.h>
48#else
49#include <sys/systm.h>
50#include <sys/kernel.h>
51#include <sys/malloc.h>
52#include <sys/bio.h>
53#include <sys/sysctl.h>
54#include <sys/proc.h>
55#include <sys/kthread.h>
56#include <sys/lock.h>
57#include <sys/mutex.h>
58#endif
59#include <sys/errno.h>
60#include <sys/sbuf.h>
61#include <geom/geom.h>
62#include <geom/geom_slice.h>
63#include <machine/stdarg.h>
64
65static g_orphan_t g_slice_orphan;
66static g_access_t g_slice_access;
67static g_start_t g_slice_start;
68
69static struct g_slicer *
70g_slice_init(unsigned nslice, unsigned scsize)
71{
72	struct g_slicer *gsp;
73
74	gsp = g_malloc(sizeof *gsp, M_WAITOK | M_ZERO);
75	gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO);
76	gsp->slices = g_malloc(nslice * sizeof(struct g_slice),
77	    M_WAITOK | M_ZERO);
78	gsp->nslice = nslice;
79	return (gsp);
80}
81
82static int
83g_slice_access(struct g_provider *pp, int dr, int dw, int de)
84{
85	int error;
86	u_int u;
87	struct g_geom *gp;
88	struct g_consumer *cp;
89	struct g_provider *pp2;
90	struct g_slicer *gsp;
91	struct g_slice *gsl, *gsl2;
92
93	gp = pp->geom;
94	cp = LIST_FIRST(&gp->consumer);
95	KASSERT (cp != NULL, ("g_slice_access but no consumer"));
96	gsp = gp->softc;
97	gsl = &gsp->slices[pp->index];
98	for (u = 0; u < gsp->nslice; u++) {
99		gsl2 = &gsp->slices[u];
100		if (gsl2->length == 0)
101			continue;
102		if (u == pp->index)
103			continue;
104		if (gsl->offset + gsl->length <= gsl2->offset)
105			continue;
106		if (gsl2->offset + gsl2->length <= gsl->offset)
107			continue;
108		/* overlap */
109		pp2 = gsl2->provider;
110		if ((pp->acw + dw) > 0 && pp2->ace > 0)
111			return (EPERM);
112		if ((pp->ace + de) > 0 && pp2->acw > 0)
113			return (EPERM);
114	}
115	/* On first open, grab an extra "exclusive" bit */
116	if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0)
117		de++;
118	/* ... and let go of it on last close */
119	if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1)
120		de--;
121	error = g_access_rel(cp, dr, dw, de);
122	return (error);
123}
124
125void
126g_slice_finish_hot(struct bio *bp)
127{
128	struct bio *bp2;
129	struct g_geom *gp;
130	struct g_consumer *cp;
131	struct g_slicer *gsp;
132	struct g_slice *gsl;
133	int idx;
134
135	KASSERT(bp->bio_to != NULL, ("NULL bio_to in g_slice_finish_hot(%p)", bp));
136	KASSERT(bp->bio_from != NULL, ("NULL bio_from in g_slice_finish_hot(%p)", bp));
137	gp = bp->bio_to->geom;
138	gsp = gp->softc;
139	cp = LIST_FIRST(&gp->consumer);
140	KASSERT(cp != NULL, ("NULL consumer in g_slice_finish_hot(%p)", bp));
141	idx = bp->bio_to->index;
142	gsl = &gsp->slices[idx];
143
144	bp2 = g_clone_bio(bp);
145	if (bp2 == NULL) {
146		g_io_deliver(bp, ENOMEM);
147		return;
148	}
149	if (bp2->bio_offset + bp2->bio_length > gsl->length)
150		bp2->bio_length = gsl->length - bp2->bio_offset;
151	bp2->bio_done = g_std_done;
152	bp2->bio_offset += gsl->offset;
153	g_io_request(bp2, cp);
154	return;
155}
156
157static void
158g_slice_start(struct bio *bp)
159{
160	struct bio *bp2;
161	struct g_provider *pp;
162	struct g_geom *gp;
163	struct g_consumer *cp;
164	struct g_slicer *gsp;
165	struct g_slice *gsl, *gmp;
166	int idx, error;
167	u_int m_index;
168	off_t t;
169
170	pp = bp->bio_to;
171	gp = pp->geom;
172	gsp = gp->softc;
173	cp = LIST_FIRST(&gp->consumer);
174	idx = pp->index;
175	gsl = &gsp->slices[idx];
176	switch(bp->bio_cmd) {
177	case BIO_READ:
178	case BIO_WRITE:
179	case BIO_DELETE:
180		if (bp->bio_offset > gsl->length) {
181			g_io_deliver(bp, EINVAL); /* XXX: EWHAT ? */
182			return;
183		}
184		/*
185		 * Check if we collide with any hot spaces, and call the
186		 * method once if so.
187		 */
188		t = bp->bio_offset + gsl->offset;
189		for (m_index = 0; m_index < gsp->nhot; m_index++) {
190			gmp = &gsp->hot[m_index];
191			if (t >= gmp->offset + gmp->length)
192				continue;
193			if (t + bp->bio_length <= gmp->offset)
194				continue;
195			error = gsp->start(bp);
196			if (error == EJUSTRETURN)
197				return;
198			else if (error) {
199				g_io_deliver(bp, error);
200				return;
201			}
202			break;
203		}
204		bp2 = g_clone_bio(bp);
205		if (bp2 == NULL) {
206			g_io_deliver(bp, ENOMEM);
207			return;
208		}
209		if (bp2->bio_offset + bp2->bio_length > gsl->length)
210			bp2->bio_length = gsl->length - bp2->bio_offset;
211		bp2->bio_done = g_std_done;
212		bp2->bio_offset += gsl->offset;
213		g_io_request(bp2, cp);
214		return;
215	case BIO_GETATTR:
216	case BIO_SETATTR:
217		/* Give the real method a chance to override */
218		if (gsp->start(bp))
219			return;
220		if (!strcmp("GEOM::frontstuff", bp->bio_attribute)) {
221			t = gsp->cfrontstuff;
222			if (gsp->frontstuff > t)
223				t = gsp->frontstuff;
224			t -= gsl->offset;
225			if (t < 0)
226				t = 0;
227			if (t > gsl->length)
228				t = gsl->length;
229			g_handleattr_off_t(bp, "GEOM::frontstuff", t);
230			return;
231		}
232#ifdef _KERNEL
233		if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) {
234			struct g_kerneldump *gkd;
235
236			gkd = (struct g_kerneldump *)bp->bio_data;
237			gkd->offset += gsp->slices[idx].offset;
238			if (gkd->length > gsp->slices[idx].length)
239				gkd->length = gsp->slices[idx].length;
240			/* now, pass it on downwards... */
241		}
242#endif
243		bp2 = g_clone_bio(bp);
244		if (bp2 == NULL) {
245			g_io_deliver(bp, ENOMEM);
246			return;
247		}
248		bp2->bio_done = g_std_done;
249		g_io_request(bp2, cp);
250		break;
251	default:
252		g_io_deliver(bp, EOPNOTSUPP);
253		return;
254	}
255}
256
257void
258g_slice_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
259{
260	struct g_slicer *gsp;
261
262	gsp = gp->softc;
263	if (indent == NULL) {
264		sbuf_printf(sb, " i %u", pp->index);
265		sbuf_printf(sb, " o %ju",
266		    (uintmax_t)gsp->slices[pp->index].offset);
267		return;
268	}
269	if (gp != NULL && (pp == NULL && cp == NULL)) {
270		sbuf_printf(sb, "%s<frontstuff>%ju</frontstuff>\n",
271		    indent, (intmax_t)gsp->frontstuff);
272	}
273	if (pp != NULL) {
274		sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index);
275		sbuf_printf(sb, "%s<length>%ju</length>\n",
276		    indent, (uintmax_t)gsp->slices[pp->index].length);
277		sbuf_printf(sb, "%s<seclength>%ju</seclength>\n", indent,
278		    (uintmax_t)gsp->slices[pp->index].length / 512);
279		sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent,
280		    (uintmax_t)gsp->slices[pp->index].offset);
281		sbuf_printf(sb, "%s<secoffset>%ju</secoffset>\n", indent,
282		    (uintmax_t)gsp->slices[pp->index].offset / 512);
283	}
284}
285
286int
287g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...)
288{
289	struct g_provider *pp;
290	struct g_slicer *gsp;
291	struct g_slice *gsl;
292	va_list ap;
293	struct sbuf *sb;
294	int error, acc;
295
296	g_trace(G_T_TOPOLOGY, "g_slice_config(%s, %d, %d)",
297	     gp->name, idx, how);
298	g_topology_assert();
299	gsp = gp->softc;
300	error = 0;
301	if (idx >= gsp->nslice)
302		return(EINVAL);
303	gsl = &gsp->slices[idx];
304	pp = gsl->provider;
305	if (pp != NULL)
306		acc = pp->acr + pp->acw + pp->ace;
307	else
308		acc = 0;
309	if (acc != 0 && how != G_SLICE_CONFIG_FORCE) {
310		if (length < gsl->length)
311			return(EBUSY);
312		if (offset != gsl->offset)
313			return(EBUSY);
314	}
315	/* XXX: check offset + length <= MEDIASIZE */
316	if (how == G_SLICE_CONFIG_CHECK)
317		return (0);
318	gsl->length = length;
319	gsl->offset = offset;
320	gsl->sectorsize = sectorsize;
321	if (length == 0) {
322		if (pp == NULL)
323			return (0);
324		if (bootverbose)
325			printf("GEOM: Deconfigure %s\n", pp->name);
326		g_orphan_provider(pp, ENXIO);
327		gsl->provider = NULL;
328		gsp->nprovider--;
329		return (0);
330	}
331	if (pp != NULL) {
332		if (bootverbose)
333			printf("GEOM: Reconfigure %s, start %jd length %jd end %jd\n",
334			    pp->name, (intmax_t)offset, (intmax_t)length,
335			    (intmax_t)(offset + length - 1));
336		pp->mediasize = gsl->length;
337		return (0);
338	}
339	va_start(ap, fmt);
340	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
341	sbuf_vprintf(sb, fmt, ap);
342	sbuf_finish(sb);
343	pp = g_new_providerf(gp, sbuf_data(sb));
344	if (bootverbose)
345		printf("GEOM: Configure %s, start %jd length %jd end %jd\n",
346		    pp->name, (intmax_t)offset, (intmax_t)length,
347		    (intmax_t)(offset + length - 1));
348	pp->index = idx;
349	pp->mediasize = gsl->length;
350	pp->sectorsize = gsl->sectorsize;
351	gsl->provider = pp;
352	gsp->nprovider++;
353	g_error_provider(pp, 0);
354	sbuf_delete(sb);
355	return(0);
356}
357
358int
359g_slice_conf_hot(struct g_geom *gp, u_int idx, off_t offset, off_t length)
360{
361	struct g_slicer *gsp;
362	struct g_slice *gsl, *gsl2;
363
364	g_trace(G_T_TOPOLOGY, "g_slice_conf_hot()");
365	g_topology_assert();
366	gsp = gp->softc;
367	gsl = gsp->hot;
368	if(idx >= gsp->nhot) {
369		gsl2 = g_malloc((idx + 1) * sizeof *gsl2, M_WAITOK | M_ZERO);
370		if (gsp->hot != NULL)
371			bcopy(gsp->hot, gsl2, gsp->nhot * sizeof *gsl2);
372		gsp->hot = gsl2;
373		if (gsp->hot != NULL)
374			g_free(gsl);
375		gsl = gsl2;
376		gsp->nhot = idx + 1;
377	}
378	if (bootverbose)
379		printf("GEOM: Add %s hot[%d] start %jd length %jd end %jd\n",
380		    gp->name, idx, (intmax_t)offset, (intmax_t)length,
381		    (intmax_t)(offset + length - 1));
382	gsl[idx].offset = offset;
383	gsl[idx].length = length;
384	return (0);
385}
386
387struct g_provider *
388g_slice_addslice(struct g_geom *gp, int idx, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...)
389{
390	struct g_provider *pp;
391	struct g_slicer *gsp;
392	va_list ap;
393	struct sbuf *sb;
394
395	g_trace(G_T_TOPOLOGY, "g_slice_addslice()");
396	g_topology_assert();
397	gsp = gp->softc;
398	va_start(ap, fmt);
399	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
400	sbuf_vprintf(sb, fmt, ap);
401	sbuf_finish(sb);
402	pp = g_new_providerf(gp, sbuf_data(sb));
403
404	pp->index = idx;
405	gsp->slices[idx].length = length;
406	gsp->slices[idx].offset = offset;
407	gsp->slices[idx].provider = pp;
408	gsp->slices[idx].sectorsize = sectorsize;
409	pp->mediasize = gsp->slices[idx].length;
410	pp->sectorsize = gsp->slices[idx].sectorsize;
411	sbuf_delete(sb);
412	if (bootverbose)
413		printf("GEOM: Add %s, start %jd length %jd end %jd\n",
414		    pp->name, (intmax_t)offset, (intmax_t)length,
415		    (intmax_t)(offset + length - 1));
416	return(pp);
417}
418
419struct g_geom *
420g_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)
421{
422	struct g_geom *gp;
423	struct g_slicer *gsp;
424	struct g_consumer *cp;
425	void **vp;
426	int error, i;
427
428	g_topology_assert();
429	vp = (void **)extrap;
430	gp = g_new_geomf(mp, "%s", pp->name);
431	gsp = g_slice_init(slices, extra);
432	gsp->start = start;
433	gp->access = g_slice_access;
434	gp->orphan = g_slice_orphan;
435	gp->softc = gsp;
436	gp->start = g_slice_start;
437	gp->spoiled = g_std_spoiled;
438	gp->dumpconf = g_slice_dumpconf;
439	cp = g_new_consumer(gp);
440	error = g_attach(cp, pp);
441	if (error == 0)
442		error = g_access_rel(cp, 1, 0, 0);
443	if (error) {
444		if (cp->provider != NULL)
445			g_detach(cp);
446		g_destroy_consumer(cp);
447		g_free(gsp->slices);
448		g_free(gp->softc);
449		g_destroy_geom(gp);
450		return (NULL);
451	}
452	/* Find out if there are any magic bytes on the consumer */
453	i = sizeof gsp->cfrontstuff;
454	error = g_io_getattr("GEOM::frontstuff", cp, &i, &gsp->cfrontstuff);
455	if (error)
456		gsp->cfrontstuff = 0;
457	*vp = gsp->softc;
458	*cpp = cp;
459	return (gp);
460}
461
462static void
463g_slice_orphan(struct g_consumer *cp)
464{
465	struct g_geom *gp;
466	struct g_provider *pp;
467	int error;
468
469	g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name);
470	g_topology_assert();
471	KASSERT(cp->provider->error != 0,
472	    ("g_slice_orphan with error == 0"));
473
474	gp = cp->geom;
475	/* XXX: Not good enough we leak the softc and its suballocations */
476	gp->flags |= G_GEOM_WITHER;
477	error = cp->provider->error;
478	LIST_FOREACH(pp, &gp->provider, provider)
479		g_orphan_provider(pp, error);
480	return;
481}
482