xref: /freebsd/sys/geom/nop/g_nop.c (revision 1d723f1d518b79fdea655f82e5419ae4888ad78c)
1 /*-
2  * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/bio.h>
37 #include <sys/sysctl.h>
38 #include <sys/malloc.h>
39 #include <geom/geom.h>
40 #include <geom/nop/g_nop.h>
41 
42 
43 SYSCTL_DECL(_kern_geom);
44 SYSCTL_NODE(_kern_geom, OID_AUTO, nop, CTLFLAG_RW, 0, "GEOM_NOP stuff");
45 static u_int g_nop_debug = 0;
46 SYSCTL_UINT(_kern_geom_nop, OID_AUTO, debug, CTLFLAG_RW, &g_nop_debug, 0,
47     "Debug level");
48 
49 static int g_nop_destroy(struct g_geom *gp, boolean_t force);
50 static int g_nop_destroy_geom(struct gctl_req *req, struct g_class *mp,
51     struct g_geom *gp);
52 static void g_nop_config(struct gctl_req *req, struct g_class *mp,
53     const char *verb);
54 static void g_nop_dumpconf(struct sbuf *sb, const char *indent,
55     struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp);
56 
57 struct g_class g_nop_class = {
58 	.name = G_NOP_CLASS_NAME,
59 	.ctlreq = g_nop_config,
60 	.destroy_geom = g_nop_destroy_geom
61 };
62 
63 
64 static void
65 g_nop_orphan(struct g_consumer *cp)
66 {
67 
68 	g_topology_assert();
69 	g_nop_destroy(cp->geom, 1);
70 }
71 
72 static void
73 g_nop_start(struct bio *bp)
74 {
75 	struct g_nop_softc *sc;
76 	struct g_geom *gp;
77 	struct g_provider *pp;
78 	struct bio *cbp;
79 
80 	gp = bp->bio_to->geom;
81 	sc = gp->softc;
82 	G_NOP_LOGREQ(bp, "Request received.");
83 	cbp = g_clone_bio(bp);
84 	if (cbp == NULL) {
85 		g_io_deliver(bp, ENOMEM);
86 		return;
87 	}
88 	pp = LIST_FIRST(&gp->provider);
89 	KASSERT(pp != NULL, ("NULL pp"));
90 	if (sc->sc_failprob > 0) {
91 		u_int rval;
92 
93 		rval = arc4random() % 100;
94 		if (rval < sc->sc_failprob) {
95 			g_io_deliver(bp, EIO);
96 			return;
97 		}
98 	}
99 	cbp->bio_done = g_std_done;
100 	cbp->bio_offset = bp->bio_offset + sc->sc_offset;
101 	cbp->bio_data = bp->bio_data;
102 	cbp->bio_length = bp->bio_length;
103 	cbp->bio_to = LIST_FIRST(&gp->provider);
104 	G_NOP_LOGREQ(cbp, "Sending request.");
105 	g_io_request(cbp, LIST_FIRST(&gp->consumer));
106 }
107 
108 static int
109 g_nop_access(struct g_provider *pp, int dr, int dw, int de)
110 {
111 	struct g_geom *gp;
112 	struct g_consumer *cp;
113 	int error;
114 
115 	gp = pp->geom;
116 	cp = LIST_FIRST(&gp->consumer);
117 	error = g_access(cp, dr, dw, de);
118 
119 	return (error);
120 }
121 
122 static int
123 g_nop_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
124     u_int failprob, off_t offset, off_t size)
125 {
126 	struct g_nop_softc *sc;
127 	struct g_geom *gp;
128 	struct g_provider *newpp;
129 	struct g_consumer *cp;
130 	char name[64];
131 	int error;
132 
133 	g_topology_assert();
134 
135 	gp = NULL;
136 	newpp = NULL;
137 	cp = NULL;
138 
139 	if ((offset % pp->sectorsize) != 0) {
140 		gctl_error(req, "Invalid offset for provider %s.", pp->name);
141 		return (EINVAL);
142 	}
143 	if ((size % pp->sectorsize) != 0) {
144 		gctl_error(req, "Invalid size for provider %s.", pp->name);
145 		return (EINVAL);
146 	}
147 	if (offset >= pp->mediasize) {
148 		gctl_error(req, "Invalid offset for provider %s.", pp->name);
149 		return (EINVAL);
150 	}
151 	if (size == 0)
152 		size = pp->mediasize - offset;
153 	if (offset + size > pp->mediasize) {
154 		gctl_error(req, "Invalid size for provider %s.", pp->name);
155 		return (EINVAL);
156 	}
157 	snprintf(name, sizeof(name), "%s%s", pp->name, G_NOP_SUFFIX);
158 	LIST_FOREACH(gp, &mp->geom, geom) {
159 		if (strcmp(gp->name, name) == 0) {
160 			gctl_error(req, "Provider %s already exists.", name);
161 			return (EEXIST);
162 		}
163 	}
164 	gp = g_new_geomf(mp, name);
165 	if (gp == NULL) {
166 		gctl_error(req, "Cannot create geom %s.", name);
167 		return (ENOMEM);
168 	}
169 	sc = g_malloc(sizeof(*sc), M_WAITOK);
170 	sc->sc_offset = offset;
171 	sc->sc_failprob = failprob;
172 	gp->softc = sc;
173 	gp->start = g_nop_start;
174 	gp->spoiled = g_nop_orphan;
175 	gp->orphan = g_nop_orphan;
176 	gp->access = g_nop_access;
177 	gp->dumpconf = g_nop_dumpconf;
178 
179 	newpp = g_new_providerf(gp, gp->name);
180 	if (newpp == NULL) {
181 		gctl_error(req, "Cannot create provider %s.", name);
182 		error = ENOMEM;
183 		goto fail;
184 	}
185 	newpp->mediasize = size;
186 	newpp->sectorsize = pp->sectorsize;
187 
188 	cp = g_new_consumer(gp);
189 	if (cp == NULL) {
190 		gctl_error(req, "Cannot create consumer for %s.", gp->name);
191 		error = ENOMEM;
192 		goto fail;
193 	}
194 	error = g_attach(cp, pp);
195 	if (error != 0) {
196 		gctl_error(req, "Cannot attach to provider %s.", pp->name);
197 		goto fail;
198 	}
199 
200 	g_error_provider(newpp, 0);
201 	G_NOP_DEBUG(0, "Device %s created.", gp->name);
202 	return (0);
203 fail:
204 	if (cp != NULL) {
205 		if (cp->provider != NULL)
206 			g_detach(cp);
207 		g_destroy_consumer(cp);
208 	}
209 	if (newpp != NULL)
210 		g_destroy_provider(pp);
211 	if (gp != NULL) {
212 		if (gp->softc != NULL)
213 			g_free(gp->softc);
214 		g_destroy_geom(gp);
215 	}
216 	return (error);
217 }
218 
219 static int
220 g_nop_destroy(struct g_geom *gp, boolean_t force)
221 {
222 	struct g_provider *pp;
223 
224 	g_topology_assert();
225 	pp = LIST_FIRST(&gp->provider);
226 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
227 		if (force) {
228 			G_NOP_DEBUG(0, "Device %s is still open, so it "
229 			    "can't be definitely removed.", pp->name);
230 		} else {
231 			G_NOP_DEBUG(1, "Device %s is still open (r%dw%de%d).",
232 			    pp->name, pp->acr, pp->acw, pp->ace);
233 			return (EBUSY);
234 		}
235 	} else {
236 		G_NOP_DEBUG(0, "Device %s removed.", gp->name);
237 	}
238 	g_free(gp->softc);
239 	gp->softc = NULL;
240 	g_wither_geom(gp, ENXIO);
241 
242 	return (0);
243 }
244 
245 static int
246 g_nop_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
247 {
248 
249 	return (g_nop_destroy(gp, 0));
250 }
251 
252 static void
253 g_nop_ctl_create(struct gctl_req *req, struct g_class *mp)
254 {
255 	struct g_provider *pp;
256 	intmax_t *failprob, *offset, *size;
257 	const char *name;
258 	char param[16];
259 	int i, *nargs;
260 
261 	g_topology_assert();
262 
263 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
264 	if (nargs == NULL) {
265 		gctl_error(req, "No '%s' argument", "nargs");
266 		return;
267 	}
268 	if (*nargs <= 0) {
269 		gctl_error(req, "Missing device(s).");
270 		return;
271 	}
272 	failprob = gctl_get_paraml(req, "failprob", sizeof(*failprob));
273 	if (failprob == NULL) {
274 		gctl_error(req, "No '%s' argument", "failprob");
275 		return;
276 	}
277 	if (*failprob < 0 || *failprob > 100) {
278 		gctl_error(req, "Invalid '%s' argument", "failprob");
279 		return;
280 	}
281 	offset = gctl_get_paraml(req, "offset", sizeof(*offset));
282 	if (offset == NULL) {
283 		gctl_error(req, "No '%s' argument", "offset");
284 		return;
285 	}
286 	if (*offset < 0) {
287 		gctl_error(req, "Invalid '%s' argument", "offset");
288 		return;
289 	}
290 	size = gctl_get_paraml(req, "size", sizeof(*size));
291 	if (size == NULL) {
292 		gctl_error(req, "No '%s' argument", "size");
293 		return;
294 	}
295 	if (*size < 0) {
296 		gctl_error(req, "Invalid '%s' argument", "size");
297 		return;
298 	}
299 
300 	for (i = 0; i < *nargs; i++) {
301 		snprintf(param, sizeof(param), "arg%d", i);
302 		name = gctl_get_asciiparam(req, param);
303 		if (name == NULL) {
304 			gctl_error(req, "No 'arg%d' argument", i);
305 			return;
306 		}
307 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
308 			name += strlen("/dev/");
309 		pp = g_provider_by_name(name);
310 		if (pp == NULL) {
311 			G_NOP_DEBUG(1, "Provider %s is invalid.", name);
312 			gctl_error(req, "Provider %s is invalid.", name);
313 			return;
314 		}
315 		if (g_nop_create(req, mp, pp, (u_int)*failprob, (off_t)*offset,
316 		    (off_t)*size) != 0) {
317 			return;
318 		}
319 	}
320 }
321 
322 static void
323 g_nop_ctl_configure(struct gctl_req *req, struct g_class *mp)
324 {
325 	struct g_nop_softc *sc;
326 	struct g_provider *pp;
327 	intmax_t *failprob;
328 	const char *name;
329 	char param[16];
330 	int i, *nargs;
331 
332 	g_topology_assert();
333 
334 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
335 	if (nargs == NULL) {
336 		gctl_error(req, "No '%s' argument", "nargs");
337 		return;
338 	}
339 	if (*nargs <= 0) {
340 		gctl_error(req, "Missing device(s).");
341 		return;
342 	}
343 	failprob = gctl_get_paraml(req, "failprob", sizeof(*failprob));
344 	if (failprob == NULL) {
345 		gctl_error(req, "No '%s' argument", "failprob");
346 		return;
347 	}
348 	if (*failprob < 0 || *failprob > 100) {
349 		gctl_error(req, "Invalid '%s' argument", "failprob");
350 		return;
351 	}
352 
353 	for (i = 0; i < *nargs; i++) {
354 		snprintf(param, sizeof(param), "arg%d", i);
355 		name = gctl_get_asciiparam(req, param);
356 		if (name == NULL) {
357 			gctl_error(req, "No 'arg%d' argument", i);
358 			return;
359 		}
360 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
361 			name += strlen("/dev/");
362 		pp = g_provider_by_name(name);
363 		if (pp == NULL || pp->geom->class != mp) {
364 			G_NOP_DEBUG(1, "Provider %s is invalid.", name);
365 			gctl_error(req, "Provider %s is invalid.", name);
366 			return;
367 		}
368 		sc = pp->geom->softc;
369 		sc->sc_failprob = (u_int)*failprob;
370 	}
371 }
372 
373 static struct g_geom *
374 g_nop_find_geom(struct g_class *mp, const char *name)
375 {
376 	struct g_geom *gp;
377 
378 	LIST_FOREACH(gp, &mp->geom, geom) {
379 		if (strcmp(gp->name, name) == 0)
380 			return (gp);
381 	}
382 	return (NULL);
383 }
384 
385 static void
386 g_nop_ctl_destroy(struct gctl_req *req, struct g_class *mp)
387 {
388 	int *nargs, *force, error, i;
389 	struct g_geom *gp;
390 	const char *name;
391 	char param[16];
392 
393 	g_topology_assert();
394 
395 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
396 	if (nargs == NULL) {
397 		gctl_error(req, "No '%s' argument", "nargs");
398 		return;
399 	}
400 	if (*nargs <= 0) {
401 		gctl_error(req, "Missing device(s).");
402 		return;
403 	}
404 	force = gctl_get_paraml(req, "force", sizeof(*force));
405 	if (force == NULL) {
406 		gctl_error(req, "No 'force' argument");
407 		return;
408 	}
409 
410 	for (i = 0; i < *nargs; i++) {
411 		snprintf(param, sizeof(param), "arg%d", i);
412 		name = gctl_get_asciiparam(req, param);
413 		if (name == NULL) {
414 			gctl_error(req, "No 'arg%d' argument", i);
415 			return;
416 		}
417 		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
418 			name += strlen("/dev/");
419 		gp = g_nop_find_geom(mp, name);
420 		if (gp == NULL) {
421 			G_NOP_DEBUG(1, "Device %s is invalid.", name);
422 			gctl_error(req, "Device %s is invalid.", name);
423 			return;
424 		}
425 		error = g_nop_destroy(gp, *force);
426 		if (error != 0) {
427 			gctl_error(req, "Cannot destroy device %s (error=%d).",
428 			    gp->name, error);
429 			return;
430 		}
431 	}
432 }
433 
434 static void
435 g_nop_config(struct gctl_req *req, struct g_class *mp, const char *verb)
436 {
437 	uint32_t *version;
438 
439 	g_topology_assert();
440 
441 	version = gctl_get_paraml(req, "version", sizeof(*version));
442 	if (version == NULL) {
443 		gctl_error(req, "No '%s' argument.", "version");
444 		return;
445 	}
446 	if (*version != G_NOP_VERSION) {
447 		gctl_error(req, "Userland and kernel parts are out of sync.");
448 		return;
449 	}
450 
451 	if (strcmp(verb, "create") == 0) {
452 		g_nop_ctl_create(req, mp);
453 		return;
454 	} else if (strcmp(verb, "configure") == 0) {
455 		g_nop_ctl_configure(req, mp);
456 		return;
457 	} else if (strcmp(verb, "destroy") == 0) {
458 		g_nop_ctl_destroy(req, mp);
459 		return;
460 	}
461 
462 	gctl_error(req, "Unknown verb.");
463 }
464 
465 static void
466 g_nop_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
467     struct g_consumer *cp, struct g_provider *pp)
468 {
469 	struct g_nop_softc *sc;
470 
471 	if (pp != NULL || cp != NULL)
472 		return;
473 	sc = gp->softc;
474 	sbuf_printf(sb, "%s<Offset>%jd</Offset>\n", indent,
475 	    (intmax_t)sc->sc_offset);
476 	sbuf_printf(sb, "%s<Failprob>%u</Failprob>\n", indent, sc->sc_failprob);
477 }
478 
479 DECLARE_GEOM_CLASS(g_nop_class, g_nop);
480