xref: /freebsd/sys/geom/geom_dev.c (revision c17d43407fe04133a94055b0dbc7ea8965654a9f)
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  * $FreeBSD$
36  */
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/kernel.h>
42 #include <sys/conf.h>
43 #include <sys/bio.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/errno.h>
47 #include <sys/time.h>
48 #include <sys/disk.h>
49 #include <sys/fcntl.h>
50 #include <geom/geom.h>
51 
52 #define CDEV_MAJOR	4
53 
54 static d_open_t		g_dev_open;
55 static d_close_t	g_dev_close;
56 static d_strategy_t	g_dev_strategy;
57 static d_ioctl_t	g_dev_ioctl;
58 static d_psize_t	g_dev_psize;
59 
60 static struct cdevsw g_dev_cdevsw = {
61         /* open */      g_dev_open,
62         /* close */     g_dev_close,
63         /* read */      physread,
64         /* write */     physwrite,
65         /* ioctl */     g_dev_ioctl,
66         /* poll */      nopoll,
67         /* mmap */      nommap,
68         /* strategy */  g_dev_strategy,
69         /* name */      "g_dev",
70         /* maj */       CDEV_MAJOR,
71         /* dump */      nodump,
72         /* psize */     g_dev_psize,
73         /* flags */     D_DISK | D_CANFREE | D_TRACKCLOSE,
74 };
75 
76 static g_taste_t g_dev_taste;
77 static g_orphan_t g_dev_orphan;
78 
79 static struct g_method g_dev_method	= {
80 	"DEV-method",
81 	g_dev_taste,
82 	NULL,
83 	g_dev_orphan,
84 	NULL,
85 	G_METHOD_INITSTUFF
86 };
87 
88 static void
89 g_dev_clone(void *arg, char *name, int namelen, dev_t *dev)
90 {
91 	struct g_geom *gp;
92 
93 	if (*dev != NODEV)
94 		return;
95 
96 	g_trace(G_T_TOPOLOGY, "g_dev_clone(%s)", name);
97 	g_rattle();
98 
99 	/* XXX: can I drop Giant here ??? */
100 	/* g_topology_lock(); */
101 	LIST_FOREACH(gp, &g_dev_method.geom, geom) {
102 		if (strcmp(gp->name, name))
103 			continue;
104 		*dev = gp->softc;
105 		g_trace(G_T_TOPOLOGY, "g_dev_clone(%s) = %p", name, *dev);
106 		return;
107 	}
108 	/* g_topology_unlock(); */
109 	return;
110 }
111 
112 static void
113 g_dev_register_cloner(void *foo __unused)
114 {
115 	static int once;
116 
117 	if (!once) {
118 		if (!once)
119 			EVENTHANDLER_REGISTER(dev_clone, g_dev_clone, 0, 1000);
120 		once++;
121 	}
122 }
123 
124 SYSINIT(geomdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,g_dev_register_cloner,NULL);
125 
126 static struct g_geom *
127 g_dev_taste(struct g_method *mp, struct g_provider *pp, struct thread *tp __unused, int insist __unused)
128 {
129 	struct g_geom *gp;
130 	struct g_consumer *cp;
131 	static int unit;
132 	u_int secsize;
133 	off_t mediasize;
134 	int error, j;
135 	dev_t dev;
136 
137 	g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name);
138 	g_topology_assert();
139 	LIST_FOREACH(cp, &pp->consumers, consumers)
140 		if (cp->geom->method == mp)
141 			return (NULL);
142 	gp = g_new_geomf(mp, pp->name);
143 	cp = g_new_consumer(gp);
144 	g_attach(cp, pp);
145 	error = g_access_rel(cp, 1, 0, 0);
146 	g_topology_unlock();
147 	if (!error) {
148 		j = sizeof secsize;
149 		error = g_io_getattr("GEOM::sectorsize", cp, &j, &secsize, tp);
150 		if (error) {
151 			secsize = 512;
152 			printf("g_bsd_taste: error %d Sectors are %d bytes\n",
153 			    error, secsize);
154 		}
155 		j = sizeof mediasize;
156 		error = g_io_getattr("GEOM::mediasize", cp, &j, &mediasize, tp);
157 		if (error) {
158 			mediasize = 0;
159 			printf("g_error %d Mediasize is %lld bytes\n",
160 			    error, mediasize);
161 		}
162 		g_topology_lock();
163 		g_access_rel(cp, -1, 0, 0);
164 		g_topology_unlock();
165 	} else {
166 		secsize = 512;
167 		mediasize = 0;
168 	}
169 	mtx_lock(&Giant);
170 	if (mediasize != 0)
171 		printf("GEOM: \"%s\" %lld bytes in %lld sectors of %u bytes\n",
172 		    pp->name, mediasize, mediasize / secsize, secsize);
173 	else
174 		printf("GEOM: \"%s\" (size unavailable)\n", pp->name);
175 	dev = make_dev(&g_dev_cdevsw, unit++,
176 	    UID_ROOT, GID_WHEEL, 0600, gp->name);
177 	gp->softc = dev;
178 	dev->si_drv1 = gp;
179 	dev->si_drv2 = cp;
180 	mtx_unlock(&Giant);
181 	g_topology_lock();
182 	return (gp);
183 }
184 
185 static int
186 g_dev_open(dev_t dev, int flags, int fmt, struct thread *td)
187 {
188 	struct g_geom *gp;
189 	struct g_consumer *cp;
190 	int error, r, w, e;
191 
192 	gp = dev->si_drv1;
193 	cp = dev->si_drv2;
194 	if (gp == NULL || cp == NULL)
195 		return(ENXIO);
196 	g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)",
197 	    gp->name, flags, fmt, td);
198 	DROP_GIANT();
199 	g_topology_lock();
200 	g_silence();
201 	r = flags & FREAD ? 1 : 0;
202 	w = flags & FWRITE ? 1 : 0;
203 	e = flags & O_EXCL ? 1 : 0;
204 	error = g_access_rel(cp, r, w, e);
205 	g_topology_unlock();
206 	PICKUP_GIANT();
207 	g_rattle();
208 	return(error);
209 }
210 
211 static int
212 g_dev_close(dev_t dev, int flags, int fmt, struct thread *td)
213 {
214 	struct g_geom *gp;
215 	struct g_consumer *cp;
216 	int error, r, w, e;
217 
218 	gp = dev->si_drv1;
219 	cp = dev->si_drv2;
220 	if (gp == NULL || cp == NULL)
221 		return(ENXIO);
222 	g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)",
223 	    gp->name, flags, fmt, td);
224 	DROP_GIANT();
225 	g_topology_lock();
226 	g_silence();
227 	r = flags & FREAD ? -1 : 0;
228 	w = flags & FWRITE ? -1 : 0;
229 	e = flags & O_EXCL ? -1 : 0;
230 	error = g_access_rel(cp, r, w, e);
231 	g_topology_unlock();
232 	PICKUP_GIANT();
233 	g_rattle();
234 	return (error);
235 }
236 
237 static int
238 g_dev_ioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
239 {
240 	struct g_geom *gp;
241 	struct g_consumer *cp;
242 	int i, error;
243 	struct g_ioctl *gio;
244 
245 	gp = dev->si_drv1;
246 	cp = dev->si_drv2;
247 
248 	error = 0;
249 	DROP_GIANT();
250 
251 	i = IOCPARM_LEN(cmd);
252 	switch (cmd) {
253 	case DIOCGSECTORSIZE:
254 		error = g_io_getattr("GEOM::sectorsize", cp, &i, data, td);
255 		break;
256 	case DIOCGMEDIASIZE:
257 		error = g_io_getattr("GEOM::mediasize", cp, &i, data, td);
258 		break;
259 	case DIOCGFWSECTORS:
260 		error = g_io_getattr("GEOM::fwsectors", cp, &i, data, td);
261 		break;
262 	case DIOCGFWHEADS:
263 		error = g_io_getattr("GEOM::fwheads", cp, &i, data, td);
264 		break;
265 	case DIOCGFWCYLINDERS:
266 		error = g_io_getattr("GEOM::fwcylinders", cp, &i, data, td);
267 		break;
268 	default:
269 		gio = g_malloc(sizeof *gio, M_WAITOK);
270 		gio->cmd = cmd;
271 		gio->data = data;
272 		gio->fflag = fflag;
273 		gio->td = td;
274 		i = sizeof *gio;
275 		if (cmd & IOC_IN)
276 			error = g_io_setattr("GEOM::ioctl", cp, i, gio, td);
277 		else
278 			error = g_io_getattr("GEOM::ioctl", cp, &i, gio, td);
279 		g_free(gio);
280 		break;
281 	}
282 
283 	if (error != 0 && cmd == DIOCGDVIRGIN) {
284 		g_topology_lock();
285 		gp = g_create_geomf("BSD-method", cp->provider, NULL);
286 		g_topology_unlock();
287 	}
288 	PICKUP_GIANT();
289 	g_rattle();
290 	if (error == ENOIOCTL) {
291 		i = IOCGROUP(cmd);
292 		printf("IOCTL(0x%lx) \"%s\"", cmd, gp->name);
293 		if (i > ' ' && i <= '~')
294 			printf(" '%c'", (int)IOCGROUP(cmd));
295 		else
296 			printf(" 0x%lx", IOCGROUP(cmd));
297 		printf("/%ld ", cmd & 0xff);
298 		if (cmd & IOC_IN)
299 			printf("I");
300 		if (cmd & IOC_OUT)
301 			printf("O");
302 		printf("(%ld) = ENOIOCTL\n", IOCPARM_LEN(cmd));
303 		error = ENOTTY;
304 	}
305 	return (error);
306 }
307 
308 static int
309 g_dev_psize(dev_t dev)
310 {
311 	struct g_consumer *cp;
312 	int i, error;
313 	off_t mediasize;
314 
315 	cp = dev->si_drv2;
316 
317 	i = sizeof mediasize;
318 	error = g_io_getattr("GEOM::mediasize", cp, &i, &mediasize, NULL);
319 	if (error)
320 		return (-1);
321 	return (mediasize >> DEV_BSHIFT);
322 }
323 
324 static void
325 g_dev_done(struct bio *bp2)
326 {
327 	struct bio *bp;
328 
329 	bp = bp2->bio_linkage;
330 	bp->bio_error = bp2->bio_error;
331 	if (bp->bio_error != 0) {
332 		g_trace(G_T_BIO, "g_dev_done(%p) had error %d",
333 		    bp2, bp->bio_error);
334 		bp->bio_flags |= BIO_ERROR;
335 	} else {
336 		g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %lld",
337 		    bp2, bp, bp->bio_resid, bp2->bio_completed);
338 	}
339 	bp->bio_resid = bp->bio_bcount - bp2->bio_completed;
340 	g_destroy_bio(bp2);
341 	mtx_lock(&Giant);
342 	biodone(bp);
343 	mtx_unlock(&Giant);
344 }
345 
346 static void
347 g_dev_strategy(struct bio *bp)
348 {
349 	struct g_geom *gp;
350 	struct g_consumer *cp;
351 	struct bio *bp2;
352 	dev_t dev;
353 
354 	dev = bp->bio_dev;
355 	gp = dev->si_drv1;
356 	cp = dev->si_drv2;
357 	bp2 = g_clone_bio(bp);
358 	bp2->bio_offset = (off_t)bp->bio_blkno << DEV_BSHIFT;
359 	bp2->bio_length = (off_t)bp->bio_bcount;
360 	bp2->bio_done = g_dev_done;
361 	g_trace(G_T_BIO,
362 	    "g_dev_strategy(%p/%p) offset %lld length %lld data %p cmd %d",
363 	    bp, bp2, bp->bio_offset, bp2->bio_length, bp2->bio_data,
364 	    bp2->bio_cmd);
365 	g_io_request(bp2, cp);
366 }
367 
368 
369 static void
370 g_dev_orphan(struct g_consumer *cp, struct thread *tp)
371 {
372 	struct g_geom *gp;
373 	dev_t dev;
374 
375 	gp = cp->geom;
376 	g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, gp->name);
377 	g_topology_assert();
378 	if (cp->biocount > 0)
379 		return;
380 	dev = gp->softc;
381 	destroy_dev(dev);
382 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
383 		g_access_rel(cp, -cp->acr, -cp->acw, -cp->ace);
384 	g_dettach(cp);
385 	g_destroy_consumer(cp);
386 	g_destroy_geom(gp);
387 }
388 
389 DECLARE_GEOM_METHOD(g_dev_method, g_dev)
390 
391