geom_disk.c revision 133314 
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
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: head/sys/geom/geom_disk.c 133314 2004-08-08 06:49:07Z phk $");
38
39#include "opt_geom.h"
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/kernel.h>
44#include <sys/sysctl.h>
45#include <sys/bio.h>
46#include <sys/conf.h>
47#include <sys/fcntl.h>
48#include <sys/malloc.h>
49#include <sys/sysctl.h>
50#include <sys/devicestat.h>
51#include <machine/md_var.h>
52
53#include <sys/lock.h>
54#include <sys/mutex.h>
55#include <geom/geom.h>
56#include <geom/geom_disk.h>
57#include <geom/geom_int.h>
58
59static struct mtx g_disk_done_mtx;
60
61static g_access_t g_disk_access;
62static g_init_t g_disk_init;
63static g_fini_t g_disk_fini;
64static g_start_t g_disk_start;
65static g_ioctl_t g_disk_ioctl;
66static g_dumpconf_t g_disk_dumpconf;
67
68struct g_class g_disk_class = {
69	.name = "DISK",
70	.init = g_disk_init,
71	.fini = g_disk_fini,
72	.start = g_disk_start,
73	.access = g_disk_access,
74	.ioctl = g_disk_ioctl,
75	.dumpconf = g_disk_dumpconf,
76};
77
78static void
79g_disk_init(struct g_class *mp __unused)
80{
81
82	mtx_init(&g_disk_done_mtx, "g_disk_done", NULL, MTX_DEF);
83}
84
85static void
86g_disk_fini(struct g_class *mp __unused)
87{
88
89	mtx_destroy(&g_disk_done_mtx);
90}
91
92DECLARE_GEOM_CLASS(g_disk_class, g_disk);
93
94static void __inline
95g_disk_lock_giant(struct disk *dp)
96{
97	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
98		mtx_lock(&Giant);
99}
100
101static void __inline
102g_disk_unlock_giant(struct disk *dp)
103{
104	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
105		mtx_unlock(&Giant);
106}
107
108static int
109g_disk_access(struct g_provider *pp, int r, int w, int e)
110{
111	struct disk *dp;
112	int error;
113
114	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
115	    pp->name, r, w, e);
116	g_topology_assert();
117	dp = pp->geom->softc;
118	if (dp == NULL || dp->d_destroyed) {
119		/*
120		 * Allow decreasing access count even if disk is not
121		 * avaliable anymore.
122		 */
123		if (r <= 0 && w <= 0 && e <= 0)
124			return (0);
125		return (ENXIO);
126	}
127	r += pp->acr;
128	w += pp->acw;
129	e += pp->ace;
130	error = 0;
131	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
132		if (dp->d_open != NULL) {
133			g_disk_lock_giant(dp);
134			error = dp->d_open(dp);
135			if (error != 0)
136				printf("Opened disk %s -> %d\n",
137				    pp->name, error);
138			g_disk_unlock_giant(dp);
139		}
140		pp->mediasize = dp->d_mediasize;
141		pp->sectorsize = dp->d_sectorsize;
142		dp->d_flags |= DISKFLAG_OPEN;
143		if (dp->d_maxsize == 0) {
144			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
145			    dp->d_name, dp->d_unit);
146			dp->d_maxsize = DFLTPHYS;
147		}
148	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
149		if (dp->d_close != NULL) {
150			g_disk_lock_giant(dp);
151			error = dp->d_close(dp);
152			if (error != 0)
153				printf("Closed disk %s -> %d\n",
154				    pp->name, error);
155			g_disk_unlock_giant(dp);
156		}
157		dp->d_flags &= ~DISKFLAG_OPEN;
158	}
159	return (error);
160}
161
162static void
163g_disk_kerneldump(struct bio *bp, struct disk *dp)
164{
165	int error;
166	struct g_kerneldump *gkd;
167	struct dumperinfo di;
168	struct g_geom *gp;
169
170	gkd = (struct g_kerneldump*)bp->bio_data;
171	gp = bp->bio_to->geom;
172	g_trace(G_T_TOPOLOGY, "g_disk_kernedump(%s, %jd, %jd)",
173		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
174	if (dp->d_dump == NULL) {
175		g_io_deliver(bp, ENODEV);
176		return;
177	}
178	di.dumper = dp->d_dump;
179	di.priv = dp;
180	di.blocksize = dp->d_sectorsize;
181	di.mediaoffset = gkd->offset;
182	di.mediasize = gkd->length;
183	error = set_dumper(&di);
184	g_io_deliver(bp, error);
185}
186
187static void
188g_disk_done(struct bio *bp)
189{
190	struct bio *bp2;
191	struct disk *dp;
192
193	/* See "notes" for why we need a mutex here */
194	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
195	mtx_lock(&g_disk_done_mtx);
196	bp->bio_completed = bp->bio_length - bp->bio_resid;
197
198	bp2 = bp->bio_parent;
199	if (bp2->bio_error == 0)
200		bp2->bio_error = bp->bio_error;
201	bp2->bio_completed += bp->bio_completed;
202	g_destroy_bio(bp);
203	bp2->bio_inbed++;
204	if (bp2->bio_children == bp2->bio_inbed) {
205		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
206		if ((dp = bp2->bio_to->geom->softc))
207			devstat_end_transaction_bio(dp->d_devstat, bp2);
208		g_io_deliver(bp2, bp2->bio_error);
209	}
210	mtx_unlock(&g_disk_done_mtx);
211}
212
213static int
214g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, struct thread *td)
215{
216	struct g_geom *gp;
217	struct disk *dp;
218	int error;
219
220	gp = pp->geom;
221	dp = gp->softc;
222
223	if (dp->d_ioctl == NULL)
224		return (ENOIOCTL);
225	g_disk_lock_giant(dp);
226	error = dp->d_ioctl(dp, cmd, data, 0, td);
227	g_disk_unlock_giant(dp);
228	return(error);
229}
230
231static void
232g_disk_start(struct bio *bp)
233{
234	struct bio *bp2, *bp3;
235	struct disk *dp;
236	int error;
237	off_t off;
238
239	dp = bp->bio_to->geom->softc;
240	if (dp == NULL || dp->d_destroyed)
241		g_io_deliver(bp, ENXIO);
242	error = EJUSTRETURN;
243	switch(bp->bio_cmd) {
244	case BIO_DELETE:
245		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
246			error = 0;
247			break;
248		}
249		/* fall-through */
250	case BIO_READ:
251	case BIO_WRITE:
252		off = 0;
253		bp3 = NULL;
254		bp2 = g_clone_bio(bp);
255		if (bp2 == NULL) {
256			error = ENOMEM;
257			break;
258		}
259		devstat_start_transaction_bio(dp->d_devstat, bp);
260		do {
261			bp2->bio_offset += off;
262			bp2->bio_length -= off;
263			bp2->bio_data += off;
264			if (bp2->bio_length > dp->d_maxsize) {
265				/*
266				 * XXX: If we have a stripesize we should really
267				 * use it here.
268				 */
269				bp2->bio_length = dp->d_maxsize;
270				off += dp->d_maxsize;
271				/*
272				 * To avoid a race, we need to grab the next bio
273				 * before we schedule this one.  See "notes".
274				 */
275				bp3 = g_clone_bio(bp);
276				if (bp3 == NULL)
277					bp->bio_error = ENOMEM;
278			}
279			bp2->bio_done = g_disk_done;
280			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
281			bp2->bio_bcount = bp2->bio_length;
282			bp2->bio_disk = dp;
283			g_disk_lock_giant(dp);
284			dp->d_strategy(bp2);
285			g_disk_unlock_giant(dp);
286			bp2 = bp3;
287			bp3 = NULL;
288		} while (bp2 != NULL);
289		break;
290	case BIO_GETATTR:
291		if (g_handleattr_int(bp, "GEOM::fwsectors", dp->d_fwsectors))
292			break;
293		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
294			break;
295		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
296			break;
297		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
298			g_disk_kerneldump(bp, dp);
299		else
300			error = ENOIOCTL;
301		break;
302	default:
303		error = EOPNOTSUPP;
304		break;
305	}
306	if (error != EJUSTRETURN)
307		g_io_deliver(bp, error);
308	return;
309}
310
311static void
312g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
313{
314	struct disk *dp;
315
316	dp = gp->softc;
317	if (dp == NULL)
318		return;
319	if (indent == NULL) {
320		sbuf_printf(sb, " hd %u", dp->d_fwheads);
321		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
322		return;
323	}
324	if (pp != NULL) {
325		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
326		    indent, dp->d_fwheads);
327		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
328		    indent, dp->d_fwsectors);
329	}
330}
331
332static void
333g_disk_create(void *arg, int flag)
334{
335	struct g_geom *gp;
336	struct g_provider *pp;
337	struct disk *dp;
338
339	if (flag == EV_CANCEL)
340		return;
341	g_topology_assert();
342	dp = arg;
343	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
344	gp->softc = dp;
345	pp = g_new_providerf(gp, "%s", gp->name);
346	pp->mediasize = dp->d_mediasize;
347	pp->sectorsize = dp->d_sectorsize;
348	if (dp->d_flags & DISKFLAG_CANDELETE)
349		pp->flags |= G_PF_CANDELETE;
350	pp->stripeoffset = dp->d_stripeoffset;
351	pp->stripesize = dp->d_stripesize;
352	if (bootverbose)
353		printf("GEOM: new disk %s\n", gp->name);
354	dp->d_geom = gp;
355	g_error_provider(pp, 0);
356}
357
358static void
359g_disk_destroy(void *ptr, int flag)
360{
361	struct disk *dp;
362	struct g_geom *gp;
363
364	g_topology_assert();
365	dp = ptr;
366	gp = dp->d_geom;
367	gp->softc = NULL;
368	g_wither_geom(gp, ENXIO);
369	g_free(dp);
370}
371
372struct disk *
373disk_alloc()
374{
375	struct disk *dp;
376
377	dp = g_malloc(sizeof *dp, M_WAITOK | M_ZERO);
378	return (dp);
379}
380
381void
382disk_create(struct disk *dp, int version)
383{
384	if (version != DISK_VERSION_00) {
385		printf("WARNING: Attempt to add disk %s%d %s",
386		    dp->d_name, dp->d_unit,
387		    " using incompatible ABI version of disk(9)\n");
388		printf("WARNING: Ignoring disk %s%d\n",
389		    dp->d_name, dp->d_unit);
390		return;
391	}
392	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
393	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
394	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
395	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
396	if (dp->d_devstat == NULL)
397		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
398		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
399		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
400	dp->d_geom = NULL;
401	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
402}
403
404void
405disk_destroy(struct disk *dp)
406{
407
408	g_cancel_event(dp);
409	dp->d_destroyed = 1;
410	if (dp->d_devstat != NULL)
411		devstat_remove_entry(dp->d_devstat);
412	g_post_event(g_disk_destroy, dp, M_WAITOK, NULL);
413}
414
415static void
416g_kern_disks(void *p, int flag __unused)
417{
418	struct sbuf *sb;
419	struct g_geom *gp;
420	char *sp;
421
422	sb = p;
423	sp = "";
424	g_topology_assert();
425	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
426		sbuf_printf(sb, "%s%s", sp, gp->name);
427		sp = " ";
428	}
429	sbuf_finish(sb);
430}
431
432static int
433sysctl_disks(SYSCTL_HANDLER_ARGS)
434{
435	int error;
436	struct sbuf *sb;
437
438	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
439	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
440	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
441	sbuf_delete(sb);
442	return error;
443}
444
445SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NOLOCK, 0, 0,
446    sysctl_disks, "A", "names of available disks");
447
448