geom_disk.c revision 120374 
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 120374 2003-09-23 07:53:59Z 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;
64
65struct g_class g_disk_class = {
66	.name = "DISK",
67	.init = g_disk_init,
68	.fini = g_disk_fini,
69};
70
71static void
72g_disk_init(struct g_class *mp __unused)
73{
74
75	mtx_init(&g_disk_done_mtx, "g_disk_done", MTX_DEF, 0);
76}
77
78static void
79g_disk_fini(struct g_class *mp __unused)
80{
81
82	mtx_destroy(&g_disk_done_mtx);
83}
84
85DECLARE_GEOM_CLASS(g_disk_class, g_disk);
86
87static void __inline
88g_disk_lock_giant(struct disk *dp)
89{
90	if (dp->d_flags & DISKFLAG_NOGIANT)
91		return;
92	mtx_lock(&Giant);
93}
94
95static void __inline
96g_disk_unlock_giant(struct disk *dp)
97{
98	if (dp->d_flags & DISKFLAG_NOGIANT)
99		return;
100	mtx_unlock(&Giant);
101}
102
103static int
104g_disk_access(struct g_provider *pp, int r, int w, int e)
105{
106	struct disk *dp;
107	int error;
108
109	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
110	    pp->name, r, w, e);
111	g_topology_assert();
112	r += pp->acr;
113	w += pp->acw;
114	e += pp->ace;
115	dp = pp->geom->softc;
116	if (dp == NULL)
117		return (ENXIO);
118	error = 0;
119	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
120		if (dp->d_open != NULL) {
121			g_disk_lock_giant(dp);
122			error = dp->d_open(dp);
123			if (error != 0)
124				printf("Opened disk %s -> %d\n",
125				    pp->name, error);
126			g_disk_unlock_giant(dp);
127		}
128		pp->mediasize = dp->d_mediasize;
129		pp->sectorsize = dp->d_sectorsize;
130		dp->d_flags |= DISKFLAG_OPEN;
131		if (dp->d_maxsize == 0) {
132			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
133			    dp->d_name, dp->d_unit);
134			dp->d_maxsize = DFLTPHYS;
135		}
136	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
137		if (dp->d_close != NULL) {
138			g_disk_lock_giant(dp);
139			error = dp->d_close(dp);
140			if (error != 0)
141				printf("Closed disk %s -> %d\n",
142				    pp->name, error);
143			g_disk_unlock_giant(dp);
144		}
145		dp->d_flags &= ~DISKFLAG_OPEN;
146	}
147	return (error);
148}
149
150static void
151g_disk_kerneldump(struct bio *bp, struct disk *dp)
152{
153	int error;
154	struct g_kerneldump *gkd;
155	struct dumperinfo di;
156	struct g_geom *gp;
157
158	gkd = (struct g_kerneldump*)bp->bio_data;
159	gp = bp->bio_to->geom;
160	g_trace(G_T_TOPOLOGY, "g_disk_kernedump(%s, %jd, %jd)",
161		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
162	di.dumper = dp->d_dump;
163	di.priv = dp;
164	di.blocksize = dp->d_sectorsize;
165	di.mediaoffset = gkd->offset;
166	di.mediasize = gkd->length;
167	error = set_dumper(&di);
168	g_io_deliver(bp, error);
169}
170
171static void
172g_disk_done(struct bio *bp)
173{
174	struct bio *bp2;
175	struct disk *dp;
176
177	/* See "notes" for why we need a mutex here */
178	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
179	mtx_lock(&g_disk_done_mtx);
180	bp->bio_completed = bp->bio_length - bp->bio_resid;
181
182	bp2 = bp->bio_parent;
183	dp = bp2->bio_to->geom->softc;
184	if (bp2->bio_error == 0)
185		bp2->bio_error = bp->bio_error;
186	bp2->bio_completed += bp->bio_completed;
187	g_destroy_bio(bp);
188	bp2->bio_inbed++;
189	if (bp2->bio_children == bp2->bio_inbed) {
190		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
191		devstat_end_transaction_bio(dp->d_devstat, bp2);
192		g_io_deliver(bp2, bp2->bio_error);
193	}
194	mtx_unlock(&g_disk_done_mtx);
195}
196
197static int
198g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, struct thread *td)
199{
200	struct g_geom *gp;
201	struct disk *dp;
202	int error;
203
204	gp = pp->geom;
205	dp = gp->softc;
206
207	if (dp->d_ioctl == NULL)
208		return (ENOIOCTL);
209	g_disk_lock_giant(dp);
210	error = dp->d_ioctl(dp, cmd, data, 0, td);
211	g_disk_unlock_giant(dp);
212	return(error);
213}
214
215static void
216g_disk_start(struct bio *bp)
217{
218	struct bio *bp2, *bp3;
219	struct disk *dp;
220	int error;
221	off_t off;
222
223	dp = bp->bio_to->geom->softc;
224	if (dp == NULL)
225		g_io_deliver(bp, ENXIO);
226	error = EJUSTRETURN;
227	switch(bp->bio_cmd) {
228	case BIO_DELETE:
229		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
230			error = 0;
231			break;
232		}
233		/* fall-through */
234	case BIO_READ:
235	case BIO_WRITE:
236		off = 0;
237		bp3 = NULL;
238		bp2 = g_clone_bio(bp);
239		if (bp2 == NULL) {
240			error = ENOMEM;
241			break;
242		}
243		devstat_start_transaction_bio(dp->d_devstat, bp);
244		do {
245			bp2->bio_offset += off;
246			bp2->bio_length -= off;
247			bp2->bio_data += off;
248			if (bp2->bio_length > dp->d_maxsize) {
249				/*
250				 * XXX: If we have a stripesize we should really
251				 * use it here.
252				 */
253				bp2->bio_length = dp->d_maxsize;
254				off += dp->d_maxsize;
255				/*
256				 * To avoid a race, we need to grab the next bio
257				 * before we schedule this one.  See "notes".
258				 */
259				bp3 = g_clone_bio(bp);
260				if (bp3 == NULL)
261					bp->bio_error = ENOMEM;
262			}
263			bp2->bio_done = g_disk_done;
264			bp2->bio_blkno = bp2->bio_offset >> DEV_BSHIFT;
265			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
266			bp2->bio_bcount = bp2->bio_length;
267			bp2->bio_disk = dp;
268			g_disk_lock_giant(dp);
269			dp->d_strategy(bp2);
270			g_disk_unlock_giant(dp);
271			bp2 = bp3;
272			bp3 = NULL;
273		} while (bp2 != NULL);
274		break;
275	case BIO_GETATTR:
276		if (g_handleattr_int(bp, "GEOM::fwsectors", dp->d_fwsectors))
277			break;
278		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
279			break;
280		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
281			break;
282		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
283			g_disk_kerneldump(bp, dp);
284		else
285			error = ENOIOCTL;
286		break;
287	default:
288		error = EOPNOTSUPP;
289		break;
290	}
291	if (error != EJUSTRETURN)
292		g_io_deliver(bp, error);
293	return;
294}
295
296static void
297g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
298{
299	struct disk *dp;
300
301	dp = gp->softc;
302	if (dp == NULL)
303		return;
304	if (indent == NULL) {
305		sbuf_printf(sb, " hd %u", dp->d_fwheads);
306		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
307		return;
308	}
309	if (pp != NULL) {
310		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
311		    indent, dp->d_fwheads);
312		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
313		    indent, dp->d_fwsectors);
314	}
315}
316
317static void
318g_disk_create(void *arg, int flag)
319{
320	struct g_geom *gp;
321	struct g_provider *pp;
322	struct disk *dp;
323
324	if (flag == EV_CANCEL)
325		return;
326	g_topology_assert();
327	dp = arg;
328	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
329	gp->start = g_disk_start;
330	gp->access = g_disk_access;
331	gp->ioctl = g_disk_ioctl;
332	gp->softc = dp;
333	gp->dumpconf = g_disk_dumpconf;
334	pp = g_new_providerf(gp, "%s", gp->name);
335	pp->mediasize = dp->d_mediasize;
336	pp->sectorsize = dp->d_sectorsize;
337	if (dp->d_flags & DISKFLAG_CANDELETE)
338		pp->flags |= G_PF_CANDELETE;
339	pp->stripeoffset = dp->d_stripeoffset;
340	pp->stripesize = dp->d_stripesize;
341	if (bootverbose)
342		printf("GEOM: new disk %s\n", gp->name);
343	dp->d_geom = gp;
344	g_error_provider(pp, 0);
345}
346
347static void
348g_disk_destroy(void *ptr, int flag)
349{
350	struct g_geom *gp;
351
352	g_topology_assert();
353	gp = ptr;
354	gp->softc = NULL;
355	g_wither_geom(gp, ENXIO);
356}
357
358void
359disk_create(int unit, struct disk *dp, int flags, void *unused __unused, void * unused2 __unused)
360{
361
362	dp->d_unit = unit;
363	dp->d_flags = flags;
364	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
365	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
366	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
367	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
368	if (bootverbose || 1)
369		printf("GEOM: create disk %s%d dp=%p\n",
370		    dp->d_name, dp->d_unit, dp);
371	if (dp->d_devstat == NULL)
372		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
373		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
374		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
375	dp->d_geom = NULL;
376	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
377}
378
379void
380disk_destroy(struct disk *dp)
381{
382	struct g_geom *gp;
383
384	if (bootverbose || 1)
385		printf("GEOM: destroy disk %s%d dp=%p\n",
386		    dp->d_name, dp->d_unit, dp);
387	g_cancel_event(dp);
388	gp = dp->d_geom;
389	if (gp == NULL)
390		return;
391	gp->softc = NULL;
392	devstat_remove_entry(dp->d_devstat);
393	g_waitfor_event(g_disk_destroy, gp, M_WAITOK, NULL, NULL);
394	dp->d_geom = NULL;
395}
396
397static void
398g_kern_disks(void *p, int flag __unused)
399{
400	struct sbuf *sb;
401	struct g_geom *gp;
402	char *sp;
403
404	sb = p;
405	sp = "";
406	g_topology_assert();
407	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
408		sbuf_printf(sb, "%s%s", sp, gp->name);
409		sp = " ";
410	}
411	sbuf_finish(sb);
412}
413
414static int
415sysctl_disks(SYSCTL_HANDLER_ARGS)
416{
417	int error;
418	struct sbuf *sb;
419
420	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
421	sbuf_clear(sb);
422	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
423	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
424	sbuf_delete(sb);
425	return error;
426}
427
428SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NOLOCK, 0, 0,
429    sysctl_disks, "A", "names of available disks");
430
431