xref: /freebsd/sys/geom/geom_disk.c (revision f0a75d274af375d15b97b830966b99a02b7db911) 
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("$FreeBSD$");
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 
59 static struct mtx g_disk_done_mtx;
60 
61 static g_access_t g_disk_access;
62 static g_init_t g_disk_init;
63 static g_fini_t g_disk_fini;
64 static g_start_t g_disk_start;
65 static g_ioctl_t g_disk_ioctl;
66 static g_dumpconf_t g_disk_dumpconf;
67 
68 static struct g_class g_disk_class = {
69 	.name = "DISK",
70 	.version = G_VERSION,
71 	.init = g_disk_init,
72 	.fini = g_disk_fini,
73 	.start = g_disk_start,
74 	.access = g_disk_access,
75 	.ioctl = g_disk_ioctl,
76 	.dumpconf = g_disk_dumpconf,
77 };
78 
79 static void
80 g_disk_init(struct g_class *mp __unused)
81 {
82 
83 	mtx_init(&g_disk_done_mtx, "g_disk_done", NULL, MTX_DEF);
84 }
85 
86 static void
87 g_disk_fini(struct g_class *mp __unused)
88 {
89 
90 	mtx_destroy(&g_disk_done_mtx);
91 }
92 
93 DECLARE_GEOM_CLASS(g_disk_class, g_disk);
94 
95 static void __inline
96 g_disk_lock_giant(struct disk *dp)
97 {
98 	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
99 		mtx_lock(&Giant);
100 }
101 
102 static void __inline
103 g_disk_unlock_giant(struct disk *dp)
104 {
105 	if (dp->d_flags & DISKFLAG_NEEDSGIANT)
106 		mtx_unlock(&Giant);
107 }
108 
109 static int
110 g_disk_access(struct g_provider *pp, int r, int w, int e)
111 {
112 	struct disk *dp;
113 	int error;
114 
115 	g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
116 	    pp->name, r, w, e);
117 	g_topology_assert();
118 	dp = pp->geom->softc;
119 	if (dp == NULL || dp->d_destroyed) {
120 		/*
121 		 * Allow decreasing access count even if disk is not
122 		 * avaliable anymore.
123 		 */
124 		if (r <= 0 && w <= 0 && e <= 0)
125 			return (0);
126 		return (ENXIO);
127 	}
128 	r += pp->acr;
129 	w += pp->acw;
130 	e += pp->ace;
131 	error = 0;
132 	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
133 		if (dp->d_open != NULL) {
134 			g_disk_lock_giant(dp);
135 			error = dp->d_open(dp);
136 			if (bootverbose && error != 0)
137 				printf("Opened disk %s -> %d\n",
138 				    pp->name, error);
139 			g_disk_unlock_giant(dp);
140 		}
141 		pp->mediasize = dp->d_mediasize;
142 		pp->sectorsize = dp->d_sectorsize;
143 		dp->d_flags |= DISKFLAG_OPEN;
144 		if (dp->d_maxsize == 0) {
145 			printf("WARNING: Disk drive %s%d has no d_maxsize\n",
146 			    dp->d_name, dp->d_unit);
147 			dp->d_maxsize = DFLTPHYS;
148 		}
149 	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
150 		if (dp->d_close != NULL) {
151 			g_disk_lock_giant(dp);
152 			error = dp->d_close(dp);
153 			if (error != 0)
154 				printf("Closed disk %s -> %d\n",
155 				    pp->name, error);
156 			g_disk_unlock_giant(dp);
157 		}
158 		dp->d_flags &= ~DISKFLAG_OPEN;
159 	}
160 	return (error);
161 }
162 
163 static void
164 g_disk_kerneldump(struct bio *bp, struct disk *dp)
165 {
166 	int error;
167 	struct g_kerneldump *gkd;
168 	struct dumperinfo di;
169 	struct g_geom *gp;
170 
171 	gkd = (struct g_kerneldump*)bp->bio_data;
172 	gp = bp->bio_to->geom;
173 	g_trace(G_T_TOPOLOGY, "g_disk_kernedump(%s, %jd, %jd)",
174 		gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
175 	if (dp->d_dump == NULL) {
176 		g_io_deliver(bp, ENODEV);
177 		return;
178 	}
179 	di.dumper = dp->d_dump;
180 	di.priv = dp;
181 	di.blocksize = dp->d_sectorsize;
182 	di.mediaoffset = gkd->offset;
183 	if ((gkd->offset + gkd->length) > dp->d_mediasize)
184 		gkd->length = dp->d_mediasize - gkd->offset;
185 	di.mediasize = gkd->length;
186 	error = set_dumper(&di);
187 	g_io_deliver(bp, error);
188 }
189 
190 static void
191 g_disk_done(struct bio *bp)
192 {
193 	struct bio *bp2;
194 	struct disk *dp;
195 
196 	/* See "notes" for why we need a mutex here */
197 	/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
198 	mtx_lock(&g_disk_done_mtx);
199 	bp->bio_completed = bp->bio_length - bp->bio_resid;
200 
201 	bp2 = bp->bio_parent;
202 	if (bp2->bio_error == 0)
203 		bp2->bio_error = bp->bio_error;
204 	bp2->bio_completed += bp->bio_completed;
205 	if ((bp->bio_cmd & (BIO_READ|BIO_WRITE|BIO_DELETE)) &&
206 	    (dp = bp2->bio_to->geom->softc)) {
207 		devstat_end_transaction_bio(dp->d_devstat, bp);
208 	}
209 	g_destroy_bio(bp);
210 	bp2->bio_inbed++;
211 	if (bp2->bio_children == bp2->bio_inbed) {
212 		bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
213 		g_io_deliver(bp2, bp2->bio_error);
214 	}
215 	mtx_unlock(&g_disk_done_mtx);
216 }
217 
218 static int
219 g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, int fflag, struct thread *td)
220 {
221 	struct g_geom *gp;
222 	struct disk *dp;
223 	int error;
224 
225 	gp = pp->geom;
226 	dp = gp->softc;
227 
228 	if (dp->d_ioctl == NULL)
229 		return (ENOIOCTL);
230 	g_disk_lock_giant(dp);
231 	error = dp->d_ioctl(dp, cmd, data, fflag, td);
232 	g_disk_unlock_giant(dp);
233 	return(error);
234 }
235 
236 static void
237 g_disk_start(struct bio *bp)
238 {
239 	struct bio *bp2, *bp3;
240 	struct disk *dp;
241 	int error;
242 	off_t off;
243 
244 	dp = bp->bio_to->geom->softc;
245 	if (dp == NULL || dp->d_destroyed) {
246 		g_io_deliver(bp, ENXIO);
247 		return;
248 	}
249 	error = EJUSTRETURN;
250 	switch(bp->bio_cmd) {
251 	case BIO_DELETE:
252 		if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
253 			error = 0;
254 			break;
255 		}
256 		/* fall-through */
257 	case BIO_READ:
258 	case BIO_WRITE:
259 		off = 0;
260 		bp3 = NULL;
261 		bp2 = g_clone_bio(bp);
262 		if (bp2 == NULL) {
263 			error = ENOMEM;
264 			break;
265 		}
266 		do {
267 			bp2->bio_offset += off;
268 			bp2->bio_length -= off;
269 			bp2->bio_data += off;
270 			if (bp2->bio_length > dp->d_maxsize) {
271 				/*
272 				 * XXX: If we have a stripesize we should really
273 				 * use it here.
274 				 */
275 				bp2->bio_length = dp->d_maxsize;
276 				off += dp->d_maxsize;
277 				/*
278 				 * To avoid a race, we need to grab the next bio
279 				 * before we schedule this one.  See "notes".
280 				 */
281 				bp3 = g_clone_bio(bp);
282 				if (bp3 == NULL)
283 					bp->bio_error = ENOMEM;
284 			}
285 			bp2->bio_done = g_disk_done;
286 			bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
287 			bp2->bio_bcount = bp2->bio_length;
288 			bp2->bio_disk = dp;
289 			devstat_start_transaction_bio(dp->d_devstat, bp2);
290 			g_disk_lock_giant(dp);
291 			dp->d_strategy(bp2);
292 			g_disk_unlock_giant(dp);
293 			bp2 = bp3;
294 			bp3 = NULL;
295 		} while (bp2 != NULL);
296 		break;
297 	case BIO_GETATTR:
298 		if (g_handleattr_int(bp, "GEOM::fwsectors", dp->d_fwsectors))
299 			break;
300 		else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
301 			break;
302 		else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
303 			break;
304 		else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
305 			g_disk_kerneldump(bp, dp);
306 		else
307 			error = ENOIOCTL;
308 		break;
309 	case BIO_FLUSH:
310 		g_trace(G_T_TOPOLOGY, "g_disk_flushcache(%s)",
311 		    bp->bio_to->name);
312 		if (!(dp->d_flags & DISKFLAG_CANFLUSHCACHE)) {
313 			g_io_deliver(bp, ENODEV);
314 			return;
315 		}
316 		bp2 = g_clone_bio(bp);
317 		if (bp2 == NULL) {
318 			g_io_deliver(bp, ENOMEM);
319 			return;
320 		}
321 		bp2->bio_done = g_disk_done;
322 		bp2->bio_disk = dp;
323 		g_disk_lock_giant(dp);
324 		dp->d_strategy(bp2);
325 		g_disk_unlock_giant(dp);
326 		break;
327 	default:
328 		error = EOPNOTSUPP;
329 		break;
330 	}
331 	if (error != EJUSTRETURN)
332 		g_io_deliver(bp, error);
333 	return;
334 }
335 
336 static void
337 g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
338 {
339 	struct disk *dp;
340 
341 	dp = gp->softc;
342 	if (dp == NULL)
343 		return;
344 	if (indent == NULL) {
345 		sbuf_printf(sb, " hd %u", dp->d_fwheads);
346 		sbuf_printf(sb, " sc %u", dp->d_fwsectors);
347 		return;
348 	}
349 	if (pp != NULL) {
350 		sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
351 		    indent, dp->d_fwheads);
352 		sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
353 		    indent, dp->d_fwsectors);
354 	}
355 }
356 
357 static void
358 g_disk_create(void *arg, int flag)
359 {
360 	struct g_geom *gp;
361 	struct g_provider *pp;
362 	struct disk *dp;
363 
364 	if (flag == EV_CANCEL)
365 		return;
366 	g_topology_assert();
367 	dp = arg;
368 	gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
369 	gp->softc = dp;
370 	pp = g_new_providerf(gp, "%s", gp->name);
371 	pp->mediasize = dp->d_mediasize;
372 	pp->sectorsize = dp->d_sectorsize;
373 	if (dp->d_flags & DISKFLAG_CANDELETE)
374 		pp->flags |= G_PF_CANDELETE;
375 	pp->stripeoffset = dp->d_stripeoffset;
376 	pp->stripesize = dp->d_stripesize;
377 	if (bootverbose)
378 		printf("GEOM: new disk %s\n", gp->name);
379 	dp->d_geom = gp;
380 	g_error_provider(pp, 0);
381 }
382 
383 static void
384 g_disk_destroy(void *ptr, int flag)
385 {
386 	struct disk *dp;
387 	struct g_geom *gp;
388 
389 	g_topology_assert();
390 	dp = ptr;
391 	gp = dp->d_geom;
392 	if (gp != NULL) {
393 		gp->softc = NULL;
394 		g_wither_geom(gp, ENXIO);
395 	}
396 	g_free(dp);
397 }
398 
399 struct disk *
400 disk_alloc()
401 {
402 	struct disk *dp;
403 
404 	dp = g_malloc(sizeof *dp, M_WAITOK | M_ZERO);
405 	return (dp);
406 }
407 
408 void
409 disk_create(struct disk *dp, int version)
410 {
411 	if (version != DISK_VERSION_00) {
412 		printf("WARNING: Attempt to add disk %s%d %s",
413 		    dp->d_name, dp->d_unit,
414 		    " using incompatible ABI version of disk(9)\n");
415 		printf("WARNING: Ignoring disk %s%d\n",
416 		    dp->d_name, dp->d_unit);
417 		return;
418 	}
419 	KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
420 	KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
421 	KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
422 	KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
423 	if (dp->d_devstat == NULL)
424 		dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
425 		    dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
426 		    DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
427 	dp->d_geom = NULL;
428 	g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
429 }
430 
431 void
432 disk_destroy(struct disk *dp)
433 {
434 
435 	g_cancel_event(dp);
436 	dp->d_destroyed = 1;
437 	if (dp->d_devstat != NULL)
438 		devstat_remove_entry(dp->d_devstat);
439 	g_post_event(g_disk_destroy, dp, M_WAITOK, NULL);
440 }
441 
442 void
443 disk_gone(struct disk *dp)
444 {
445 	struct g_geom *gp;
446 	struct g_provider *pp;
447 
448 	gp = dp->d_geom;
449 	if (gp != NULL)
450 		LIST_FOREACH(pp, &gp->provider, provider)
451 			g_wither_provider(pp, ENXIO);
452 }
453 
454 static void
455 g_kern_disks(void *p, int flag __unused)
456 {
457 	struct sbuf *sb;
458 	struct g_geom *gp;
459 	char *sp;
460 
461 	sb = p;
462 	sp = "";
463 	g_topology_assert();
464 	LIST_FOREACH(gp, &g_disk_class.geom, geom) {
465 		sbuf_printf(sb, "%s%s", sp, gp->name);
466 		sp = " ";
467 	}
468 	sbuf_finish(sb);
469 }
470 
471 static int
472 sysctl_disks(SYSCTL_HANDLER_ARGS)
473 {
474 	int error;
475 	struct sbuf *sb;
476 
477 	sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
478 	g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
479 	error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
480 	sbuf_delete(sb);
481 	return error;
482 }
483 
484 SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NOLOCK, 0, 0,
485     sysctl_disks, "A", "names of available disks");
486 
487