geom_disk.c revision 125975 
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 125975 2004-02-18 21:36:53Z 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", 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_NEEDSGIANT)
91		mtx_lock(&Giant);
92}
93
94static void __inline
95g_disk_unlock_giant(struct disk *dp)
96{
97	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
98		mtx_unlock(&Giant);
99}
100
101static int
102g_disk_access(struct g_provider *pp, int r, int w, int e)
103{
104	struct disk *dp;
105	int error;
106
107	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
108	    pp->name, r, w, e);
109	g_topology_assert();
110	dp = pp->geom->softc;
111	if (dp == NULL || dp->d_destroyed) {
112		/*
113		 * Allow decreasing access count even if disk is not
114		 * avaliable anymore.
115		 */
116		if (r <= 0 && w <= 0 && e <= 0)
117			return (0);
118		return (ENXIO);
119	}
120	r += pp->acr;
121	w += pp->acw;
122	e += pp->ace;
123	error = 0;
124	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
125		if (dp->d_open != NULL) {
126			g_disk_lock_giant(dp);
127			error = dp->d_open(dp);
128			if (error != 0)
129				printf("Opened disk %s -> %d\n",
130				    pp->name, error);
131			g_disk_unlock_giant(dp);
132		}
133		pp->mediasize = dp->d_mediasize;
134		pp->sectorsize = dp->d_sectorsize;
135		dp->d_flags |= DISKFLAG_OPEN;
136		if (dp->d_maxsize == 0) {
137			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
138			    dp->d_name, dp->d_unit);
139			dp->d_maxsize = DFLTPHYS;
140		}
141	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
142		if (dp->d_close != NULL) {
143			g_disk_lock_giant(dp);
144			error = dp->d_close(dp);
145			if (error != 0)
146				printf("Closed disk %s -> %d\n",
147				    pp->name, error);
148			g_disk_unlock_giant(dp);
149		}
150		dp->d_flags &= ~DISKFLAG_OPEN;
151	}
152	return (error);
153}
154
155static void
156g_disk_kerneldump(struct bio *bp, struct disk *dp)
157{
158	int error;
159	struct g_kerneldump *gkd;
160	struct dumperinfo di;
161	struct g_geom *gp;
162
163	gkd = (struct g_kerneldump*)bp->bio_data;
164	gp = bp->bio_to->geom;
165	g_trace(G_T_TOPOLOGY, "g_disk_kernedump(%s, %jd, %jd)",
166		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
167	if (dp->d_dump == NULL) {
168		g_io_deliver(bp, ENODEV);
169		return;
170	}
171	di.dumper = dp->d_dump;
172	di.priv = dp;
173	di.blocksize = dp->d_sectorsize;
174	di.mediaoffset = gkd->offset;
175	di.mediasize = gkd->length;
176	error = set_dumper(&di);
177	g_io_deliver(bp, error);
178}
179
180static void
181g_disk_done(struct bio *bp)
182{
183	struct bio *bp2;
184	struct disk *dp;
185
186	/* See "notes" for why we need a mutex here */
187	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
188	mtx_lock(&g_disk_done_mtx);
189	bp->bio_completed = bp->bio_length - bp->bio_resid;
190
191	bp2 = bp->bio_parent;
192	dp = bp2->bio_to->geom->softc;
193	if (bp2->bio_error == 0)
194		bp2->bio_error = bp->bio_error;
195	bp2->bio_completed += bp->bio_completed;
196	g_destroy_bio(bp);
197	bp2->bio_inbed++;
198	if (bp2->bio_children == bp2->bio_inbed) {
199		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
200		devstat_end_transaction_bio(dp->d_devstat, bp2);
201		g_io_deliver(bp2, bp2->bio_error);
202	}
203	mtx_unlock(&g_disk_done_mtx);
204}
205
206static int
207g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, struct thread *td)
208{
209	struct g_geom *gp;
210	struct disk *dp;
211	int error;
212
213	gp = pp->geom;
214	dp = gp->softc;
215
216	if (dp->d_ioctl == NULL)
217		return (ENOIOCTL);
218	g_disk_lock_giant(dp);
219	error = dp->d_ioctl(dp, cmd, data, 0, td);
220	g_disk_unlock_giant(dp);
221	return(error);
222}
223
224static void
225g_disk_start(struct bio *bp)
226{
227	struct bio *bp2, *bp3;
228	struct disk *dp;
229	int error;
230	off_t off;
231
232	dp = bp->bio_to->geom->softc;
233	if (dp == NULL || dp->d_destroyed)
234		g_io_deliver(bp, ENXIO);
235	error = EJUSTRETURN;
236	switch(bp->bio_cmd) {
237	case BIO_DELETE:
238		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
239			error = 0;
240			break;
241		}
242		/* fall-through */
243	case BIO_READ:
244	case BIO_WRITE:
245		off = 0;
246		bp3 = NULL;
247		bp2 = g_clone_bio(bp);
248		if (bp2 == NULL) {
249			error = ENOMEM;
250			break;
251		}
252		devstat_start_transaction_bio(dp->d_devstat, bp);
253		do {
254			bp2->bio_offset += off;
255			bp2->bio_length -= off;
256			bp2->bio_data += off;
257			if (bp2->bio_length > dp->d_maxsize) {
258				/*
259				 * XXX: If we have a stripesize we should really
260				 * use it here.
261				 */
262				bp2->bio_length = dp->d_maxsize;
263				off += dp->d_maxsize;
264				/*
265				 * To avoid a race, we need to grab the next bio
266				 * before we schedule this one.  See "notes".
267				 */
268				bp3 = g_clone_bio(bp);
269				if (bp3 == NULL)
270					bp->bio_error = ENOMEM;
271			}
272			bp2->bio_done = g_disk_done;
273			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
274			bp2->bio_bcount = bp2->bio_length;
275			bp2->bio_disk = dp;
276			g_disk_lock_giant(dp);
277			dp->d_strategy(bp2);
278			g_disk_unlock_giant(dp);
279			bp2 = bp3;
280			bp3 = NULL;
281		} while (bp2 != NULL);
282		break;
283	case BIO_GETATTR:
284		if (g_handleattr_int(bp, "GEOM::fwsectors", dp->d_fwsectors))
285			break;
286		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
287			break;
288		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
289			break;
290		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
291			g_disk_kerneldump(bp, dp);
292		else
293			error = ENOIOCTL;
294		break;
295	default:
296		error = EOPNOTSUPP;
297		break;
298	}
299	if (error != EJUSTRETURN)
300		g_io_deliver(bp, error);
301	return;
302}
303
304static void
305g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
306{
307	struct disk *dp;
308
309	dp = gp->softc;
310	if (dp == NULL)
311		return;
312	if (indent == NULL) {
313		sbuf_printf(sb, " hd %u", dp->d_fwheads);
314		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
315		return;
316	}
317	if (pp != NULL) {
318		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
319		    indent, dp->d_fwheads);
320		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
321		    indent, dp->d_fwsectors);
322	}
323}
324
325static void
326g_disk_create(void *arg, int flag)
327{
328	struct g_geom *gp;
329	struct g_provider *pp;
330	struct disk *dp;
331
332	if (flag == EV_CANCEL)
333		return;
334	g_topology_assert();
335	dp = arg;
336	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
337	gp->start = g_disk_start;
338	gp->access = g_disk_access;
339	gp->ioctl = g_disk_ioctl;
340	gp->softc = dp;
341	gp->dumpconf = g_disk_dumpconf;
342	pp = g_new_providerf(gp, "%s", gp->name);
343	pp->mediasize = dp->d_mediasize;
344	pp->sectorsize = dp->d_sectorsize;
345	if (dp->d_flags & DISKFLAG_CANDELETE)
346		pp->flags |= G_PF_CANDELETE;
347	pp->stripeoffset = dp->d_stripeoffset;
348	pp->stripesize = dp->d_stripesize;
349	if (bootverbose)
350		printf("GEOM: new disk %s\n", gp->name);
351	dp->d_geom = gp;
352	g_error_provider(pp, 0);
353}
354
355static void
356g_disk_destroy(void *ptr, int flag)
357{
358	struct disk *dp;
359	struct g_geom *gp;
360
361	g_topology_assert();
362	dp = ptr;
363	gp = dp->d_geom;
364	gp->softc = NULL;
365	g_wither_geom(gp, ENXIO);
366	g_free(dp);
367}
368
369struct disk *
370disk_alloc()
371{
372	struct disk *dp;
373
374	dp = g_malloc(sizeof *dp, M_WAITOK | M_ZERO);
375	return (dp);
376}
377
378void
379disk_create(struct disk *dp, int version)
380{
381	if (version != DISK_VERSION_00) {
382		printf("WARNING: Attempt to add disk %s%d %s",
383		    dp->d_name, dp->d_unit,
384		    " using incompatible ABI version of disk(9)\n");
385		printf("WARNING: Ignoring disk %s%d\n",
386		    dp->d_name, dp->d_unit);
387		return;
388	}
389	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
390	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
391	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
392	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
393	if (dp->d_devstat == NULL)
394		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
395		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
396		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
397	dp->d_geom = NULL;
398	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
399}
400
401void
402disk_destroy(struct disk *dp)
403{
404
405	g_cancel_event(dp);
406	dp->d_destroyed = 1;
407	g_post_event(g_disk_destroy, dp, M_WAITOK, NULL, NULL);
408}
409
410static void
411g_kern_disks(void *p, int flag __unused)
412{
413	struct sbuf *sb;
414	struct g_geom *gp;
415	char *sp;
416
417	sb = p;
418	sp = "";
419	g_topology_assert();
420	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
421		sbuf_printf(sb, "%s%s", sp, gp->name);
422		sp = " ";
423	}
424	sbuf_finish(sb);
425}
426
427static int
428sysctl_disks(SYSCTL_HANDLER_ARGS)
429{
430	int error;
431	struct sbuf *sb;
432
433	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
434	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
435	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
436	sbuf_delete(sb);
437	return error;
438}
439
440SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NOLOCK, 0, 0,
441    sysctl_disks, "A", "names of available disks");
442
443