geom_disk.c revision 123271 
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 123271 2003-12-07 23:20:53Z truckman $");
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", NULL, MTX_DEF);
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	if (dp->d_dump == NULL) {
163		g_io_deliver(bp, ENODEV);
164		return;
165	}
166	di.dumper = dp->d_dump;
167	di.priv = dp;
168	di.blocksize = dp->d_sectorsize;
169	di.mediaoffset = gkd->offset;
170	di.mediasize = gkd->length;
171	error = set_dumper(&di);
172	g_io_deliver(bp, error);
173}
174
175static void
176g_disk_done(struct bio *bp)
177{
178	struct bio *bp2;
179	struct disk *dp;
180
181	/* See "notes" for why we need a mutex here */
182	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
183	mtx_lock(&g_disk_done_mtx);
184	bp->bio_completed = bp->bio_length - bp->bio_resid;
185
186	bp2 = bp->bio_parent;
187	dp = bp2->bio_to->geom->softc;
188	if (bp2->bio_error == 0)
189		bp2->bio_error = bp->bio_error;
190	bp2->bio_completed += bp->bio_completed;
191	g_destroy_bio(bp);
192	bp2->bio_inbed++;
193	if (bp2->bio_children == bp2->bio_inbed) {
194		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
195		devstat_end_transaction_bio(dp->d_devstat, bp2);
196		g_io_deliver(bp2, bp2->bio_error);
197	}
198	mtx_unlock(&g_disk_done_mtx);
199}
200
201static int
202g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, struct thread *td)
203{
204	struct g_geom *gp;
205	struct disk *dp;
206	int error;
207
208	gp = pp->geom;
209	dp = gp->softc;
210
211	if (dp->d_ioctl == NULL)
212		return (ENOIOCTL);
213	g_disk_lock_giant(dp);
214	error = dp->d_ioctl(dp, cmd, data, 0, td);
215	g_disk_unlock_giant(dp);
216	return(error);
217}
218
219static void
220g_disk_start(struct bio *bp)
221{
222	struct bio *bp2, *bp3;
223	struct disk *dp;
224	int error;
225	off_t off;
226
227	dp = bp->bio_to->geom->softc;
228	if (dp == NULL)
229		g_io_deliver(bp, ENXIO);
230	error = EJUSTRETURN;
231	switch(bp->bio_cmd) {
232	case BIO_DELETE:
233		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
234			error = 0;
235			break;
236		}
237		/* fall-through */
238	case BIO_READ:
239	case BIO_WRITE:
240		off = 0;
241		bp3 = NULL;
242		bp2 = g_clone_bio(bp);
243		if (bp2 == NULL) {
244			error = ENOMEM;
245			break;
246		}
247		devstat_start_transaction_bio(dp->d_devstat, bp);
248		do {
249			bp2->bio_offset += off;
250			bp2->bio_length -= off;
251			bp2->bio_data += off;
252			if (bp2->bio_length > dp->d_maxsize) {
253				/*
254				 * XXX: If we have a stripesize we should really
255				 * use it here.
256				 */
257				bp2->bio_length = dp->d_maxsize;
258				off += dp->d_maxsize;
259				/*
260				 * To avoid a race, we need to grab the next bio
261				 * before we schedule this one.  See "notes".
262				 */
263				bp3 = g_clone_bio(bp);
264				if (bp3 == NULL)
265					bp->bio_error = ENOMEM;
266			}
267			bp2->bio_done = g_disk_done;
268			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
269			bp2->bio_bcount = bp2->bio_length;
270			bp2->bio_disk = dp;
271			g_disk_lock_giant(dp);
272			dp->d_strategy(bp2);
273			g_disk_unlock_giant(dp);
274			bp2 = bp3;
275			bp3 = NULL;
276		} while (bp2 != NULL);
277		break;
278	case BIO_GETATTR:
279		if (g_handleattr_int(bp, "GEOM::fwsectors", dp->d_fwsectors))
280			break;
281		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
282			break;
283		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
284			break;
285		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
286			g_disk_kerneldump(bp, dp);
287		else
288			error = ENOIOCTL;
289		break;
290	default:
291		error = EOPNOTSUPP;
292		break;
293	}
294	if (error != EJUSTRETURN)
295		g_io_deliver(bp, error);
296	return;
297}
298
299static void
300g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
301{
302	struct disk *dp;
303
304	dp = gp->softc;
305	if (dp == NULL)
306		return;
307	if (indent == NULL) {
308		sbuf_printf(sb, " hd %u", dp->d_fwheads);
309		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
310		return;
311	}
312	if (pp != NULL) {
313		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
314		    indent, dp->d_fwheads);
315		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
316		    indent, dp->d_fwsectors);
317	}
318}
319
320static void
321g_disk_create(void *arg, int flag)
322{
323	struct g_geom *gp;
324	struct g_provider *pp;
325	struct disk *dp;
326
327	if (flag == EV_CANCEL)
328		return;
329	g_topology_assert();
330	dp = arg;
331	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
332	gp->start = g_disk_start;
333	gp->access = g_disk_access;
334	gp->ioctl = g_disk_ioctl;
335	gp->softc = dp;
336	gp->dumpconf = g_disk_dumpconf;
337	pp = g_new_providerf(gp, "%s", gp->name);
338	pp->mediasize = dp->d_mediasize;
339	pp->sectorsize = dp->d_sectorsize;
340	if (dp->d_flags & DISKFLAG_CANDELETE)
341		pp->flags |= G_PF_CANDELETE;
342	pp->stripeoffset = dp->d_stripeoffset;
343	pp->stripesize = dp->d_stripesize;
344	if (bootverbose)
345		printf("GEOM: new disk %s\n", gp->name);
346	dp->d_geom = gp;
347	g_error_provider(pp, 0);
348}
349
350static void
351g_disk_destroy(void *ptr, int flag)
352{
353	struct g_geom *gp;
354
355	g_topology_assert();
356	gp = ptr;
357	gp->softc = NULL;
358	g_wither_geom(gp, ENXIO);
359}
360
361void
362disk_create(int unit, struct disk *dp, int flags, void *unused __unused, void * unused2 __unused)
363{
364
365	dp->d_unit = unit;
366	dp->d_flags = flags;
367	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
368	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
369	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
370	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
371	if (bootverbose || 1)
372		printf("GEOM: create disk %s%d dp=%p\n",
373		    dp->d_name, dp->d_unit, dp);
374	if (dp->d_devstat == NULL)
375		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
376		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
377		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
378	dp->d_geom = NULL;
379	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
380}
381
382void
383disk_destroy(struct disk *dp)
384{
385	struct g_geom *gp;
386
387	if (bootverbose || 1)
388		printf("GEOM: destroy disk %s%d dp=%p\n",
389		    dp->d_name, dp->d_unit, dp);
390	g_cancel_event(dp);
391	gp = dp->d_geom;
392	if (gp == NULL)
393		return;
394	gp->softc = NULL;
395	devstat_remove_entry(dp->d_devstat);
396	g_waitfor_event(g_disk_destroy, gp, M_WAITOK, NULL, NULL);
397	dp->d_geom = NULL;
398}
399
400static void
401g_kern_disks(void *p, int flag __unused)
402{
403	struct sbuf *sb;
404	struct g_geom *gp;
405	char *sp;
406
407	sb = p;
408	sp = "";
409	g_topology_assert();
410	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
411		sbuf_printf(sb, "%s%s", sp, gp->name);
412		sp = " ";
413	}
414	sbuf_finish(sb);
415}
416
417static int
418sysctl_disks(SYSCTL_HANDLER_ARGS)
419{
420	int error;
421	struct sbuf *sb;
422
423	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
424	sbuf_clear(sb);
425	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
426	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
427	sbuf_delete(sb);
428	return error;
429}
430
431SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NOLOCK, 0, 0,
432    sysctl_disks, "A", "names of available disks");
433
434