g_nop.c revision 130191 
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: head/sys/geom/nop/g_nop.c 130191 2004-06-07 13:33:09Z pjd $");
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
43SYSCTL_DECL(_kern_geom);
44SYSCTL_NODE(_kern_geom, OID_AUTO, nop, CTLFLAG_RW, 0, "GEOM_NOP stuff");
45static u_int g_nop_debug = 0;
46SYSCTL_UINT(_kern_geom_nop, OID_AUTO, debug, CTLFLAG_RW, &g_nop_debug, 0,
47    "Debug level");
48
49static int g_nop_destroy(struct g_geom *gp, boolean_t force);
50static int g_nop_destroy_geom(struct gctl_req *req, struct g_class *mp,
51    struct g_geom *gp);
52static void g_nop_config(struct gctl_req *req, struct g_class *mp,
53    const char *verb);
54static void g_nop_dumpconf(struct sbuf *sb, const char *indent,
55    struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp);
56
57struct 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
64static void
65g_nop_orphan(struct g_consumer *cp)
66{
67
68	g_topology_assert();
69	g_nop_destroy(cp->geom, 1);
70}
71
72static void
73g_nop_start(struct bio *bp)
74{
75	struct g_geom *gp;
76	struct g_provider *pp;
77	struct bio *cbp;
78
79	gp = bp->bio_to->geom;
80	G_NOP_LOGREQ(bp, "Request received.");
81	cbp = g_clone_bio(bp);
82	if (cbp == NULL) {
83		g_io_deliver(bp, ENOMEM);
84		return;
85	}
86	pp = LIST_FIRST(&gp->provider);
87	KASSERT(pp != NULL, ("NULL pp"));
88	if (pp->index > 0) {
89		u_int rval;
90
91		rval = arc4random() % 100;
92		if (rval < pp->index) {
93			g_io_deliver(bp, EIO);
94			return;
95		}
96	}
97	cbp->bio_done = g_std_done;
98	cbp->bio_offset = bp->bio_offset;
99	cbp->bio_data = bp->bio_data;
100	cbp->bio_length = bp->bio_length;
101	cbp->bio_to = LIST_FIRST(&gp->provider);
102	G_NOP_LOGREQ(cbp, "Sending request.");
103	g_io_request(cbp, LIST_FIRST(&gp->consumer));
104}
105
106static int
107g_nop_access(struct g_provider *pp, int dr, int dw, int de)
108{
109	struct g_geom *gp;
110	struct g_consumer *cp;
111	int error;
112
113	gp = pp->geom;
114	cp = LIST_FIRST(&gp->consumer);
115	error = g_access(cp, dr, dw, de);
116
117	return (error);
118}
119
120static int
121g_nop_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
122    u_int failprob)
123{
124	struct g_geom *gp;
125	struct g_provider *newpp;
126	struct g_consumer *cp;
127	char name[64];
128	int error;
129
130	g_topology_assert();
131
132	gp = NULL;
133	newpp = NULL;
134	cp = NULL;
135
136	snprintf(name, sizeof(name), "%s%s", pp->name, G_NOP_SUFFIX);
137	LIST_FOREACH(gp, &mp->geom, geom) {
138		if (strcmp(gp->name, name) == 0) {
139			gctl_error(req, "Provider %s already exists.", name);
140			return (EEXIST);
141		}
142	}
143	gp = g_new_geomf(mp, name);
144	if (gp == NULL) {
145		gctl_error(req, "Cannot create geom %s%s.", name);
146		return (ENOMEM);
147	}
148	gp->softc = NULL;
149	gp->start = g_nop_start;
150	gp->spoiled = g_nop_orphan;
151	gp->orphan = g_nop_orphan;
152	gp->access = g_nop_access;
153	gp->dumpconf = g_nop_dumpconf;
154
155	newpp = g_new_providerf(gp, gp->name);
156	if (newpp == NULL) {
157		gctl_error(req, "Cannot create provider %s%s.", name);
158		error = ENOMEM;
159		goto fail;
160	}
161	newpp->mediasize = pp->mediasize;
162	newpp->sectorsize = pp->sectorsize;
163	newpp->index = failprob;
164
165	cp = g_new_consumer(gp);
166	if (cp == NULL) {
167		gctl_error(req, "Cannot create consumer for %s.", gp->name);
168		error = ENOMEM;
169		goto fail;
170	}
171	error = g_attach(cp, pp);
172	if (error != 0) {
173		gctl_error(req, "Cannot attach to provider %s.", pp->name);
174		goto fail;
175	}
176
177	g_error_provider(newpp, 0);
178	G_NOP_DEBUG(0, "Device %s created.", gp->name);
179	return (0);
180fail:
181	if (cp != NULL) {
182		if (cp->provider != NULL)
183			g_detach(cp);
184		g_destroy_consumer(cp);
185	}
186	if (newpp != NULL)
187		g_destroy_provider(pp);
188	if (gp != NULL)
189		g_destroy_geom(gp);
190	return (error);
191}
192
193static int
194g_nop_destroy(struct g_geom *gp, boolean_t force)
195{
196	struct g_provider *pp;
197
198	g_topology_assert();
199	pp = LIST_FIRST(&gp->provider);
200	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
201		if (force) {
202			G_NOP_DEBUG(0, "Device %s is still open, so it "
203			    "can't be definitely removed.", pp->name);
204		} else {
205			G_NOP_DEBUG(1, "Device %s is still open (r%dw%de%d).",
206			    pp->name, pp->acr, pp->acw, pp->ace);
207			return (EBUSY);
208		}
209	} else {
210		G_NOP_DEBUG(0, "Device %s removed.", gp->name);
211	}
212	g_wither_geom(gp, ENXIO);
213
214	return (0);
215}
216
217static int
218g_nop_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp)
219{
220
221	return (g_nop_destroy(gp, 0));
222}
223
224static void
225g_nop_ctl_create(struct gctl_req *req, struct g_class *mp)
226{
227	struct g_provider *pp;
228	intmax_t *failprob;
229	const char *name;
230	char param[16];
231	int i, *nargs;
232
233	g_topology_assert();
234
235	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
236	if (nargs == NULL) {
237		gctl_error(req, "No '%s' argument", "nargs");
238		return;
239	}
240	if (*nargs <= 0) {
241		gctl_error(req, "Missing device(s).");
242		return;
243	}
244	failprob = gctl_get_paraml(req, "failprob", sizeof(*failprob));
245	if (failprob == NULL) {
246		gctl_error(req, "No '%s' argument", "failprob");
247		return;
248	}
249	if (*failprob < 0 || *failprob > 100) {
250		gctl_error(req, "Invalid '%s' argument", "failprob");
251		return;
252	}
253
254	for (i = 0; i < *nargs; i++) {
255		snprintf(param, sizeof(param), "arg%d", i);
256		name = gctl_get_asciiparam(req, param);
257		if (name == NULL) {
258			gctl_error(req, "No 'arg%d' argument", i);
259			return;
260		}
261		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
262			name += strlen("/dev/");
263		pp = g_provider_by_name(name);
264		if (pp == NULL) {
265			G_NOP_DEBUG(1, "Provider %s is invalid.", name);
266			gctl_error(req, "Provider %s is invalid.", name);
267			return;
268		}
269		if (g_nop_create(req, mp, pp, (u_int)*failprob) != 0)
270			return;
271	}
272}
273
274static void
275g_nop_ctl_configure(struct gctl_req *req, struct g_class *mp)
276{
277	struct g_provider *pp;
278	intmax_t *failprob;
279	const char *name;
280	char param[16];
281	int i, *nargs;
282
283	g_topology_assert();
284
285	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
286	if (nargs == NULL) {
287		gctl_error(req, "No '%s' argument", "nargs");
288		return;
289	}
290	if (*nargs <= 0) {
291		gctl_error(req, "Missing device(s).");
292		return;
293	}
294	failprob = gctl_get_paraml(req, "failprob", sizeof(*failprob));
295	if (failprob == NULL) {
296		gctl_error(req, "No '%s' argument", "failprob");
297		return;
298	}
299	if (*failprob < 0 || *failprob > 100) {
300		gctl_error(req, "Invalid '%s' argument", "failprob");
301		return;
302	}
303
304	for (i = 0; i < *nargs; i++) {
305		snprintf(param, sizeof(param), "arg%d", i);
306		name = gctl_get_asciiparam(req, param);
307		if (name == NULL) {
308			gctl_error(req, "No 'arg%d' argument", i);
309			return;
310		}
311		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
312			name += strlen("/dev/");
313		pp = g_provider_by_name(name);
314		if (pp == NULL || pp->geom->class != mp) {
315			G_NOP_DEBUG(1, "Provider %s is invalid.", name);
316			gctl_error(req, "Provider %s is invalid.", name);
317			return;
318		}
319		pp->index = (u_int)*failprob;
320	}
321}
322
323static struct g_geom *
324g_nop_find_geom(struct g_class *mp, const char *name)
325{
326	struct g_geom *gp;
327
328	LIST_FOREACH(gp, &mp->geom, geom) {
329		if (strcmp(gp->name, name) == 0)
330			return (gp);
331	}
332	return (NULL);
333}
334
335static void
336g_nop_ctl_destroy(struct gctl_req *req, struct g_class *mp)
337{
338	int *nargs, *force, error, i;
339	struct g_geom *gp;
340	const char *name;
341	char param[16];
342
343	g_topology_assert();
344
345	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
346	if (nargs == NULL) {
347		gctl_error(req, "No '%s' argument", "nargs");
348		return;
349	}
350	if (*nargs <= 0) {
351		gctl_error(req, "Missing device(s).");
352		return;
353	}
354	force = gctl_get_paraml(req, "force", sizeof(*force));
355	if (force == NULL) {
356		gctl_error(req, "No 'force' argument");
357		return;
358	}
359
360	for (i = 0; i < *nargs; i++) {
361		snprintf(param, sizeof(param), "arg%d", i);
362		name = gctl_get_asciiparam(req, param);
363		if (name == NULL) {
364			gctl_error(req, "No 'arg%d' argument", i);
365			return;
366		}
367		if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
368			name += strlen("/dev/");
369		gp = g_nop_find_geom(mp, name);
370		if (gp == NULL) {
371			G_NOP_DEBUG(1, "Device %s is invalid.", name);
372			gctl_error(req, "Device %s is invalid.", name);
373			return;
374		}
375		error = g_nop_destroy(gp, *force);
376		if (error != 0) {
377			gctl_error(req, "Cannot destroy device %s (error=%d).",
378			    gp->name, error);
379			return;
380		}
381	}
382}
383
384static void
385g_nop_config(struct gctl_req *req, struct g_class *mp, const char *verb)
386{
387	uint32_t *version;
388
389	g_topology_assert();
390
391	version = gctl_get_paraml(req, "version", sizeof(*version));
392	if (version == NULL) {
393		gctl_error(req, "No '%s' argument.", "version");
394		return;
395	}
396	if (*version != G_NOP_VERSION) {
397		gctl_error(req, "Userland and kernel parts are out of sync.");
398		return;
399	}
400
401	if (strcmp(verb, "create") == 0) {
402		g_nop_ctl_create(req, mp);
403		return;
404	} else if (strcmp(verb, "configure") == 0) {
405		g_nop_ctl_configure(req, mp);
406		return;
407	} else if (strcmp(verb, "destroy") == 0) {
408		g_nop_ctl_destroy(req, mp);
409		return;
410	}
411
412	gctl_error(req, "Unknown verb.");
413}
414
415static void
416g_nop_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
417    struct g_consumer *cp, struct g_provider *pp)
418{
419
420	if (pp != NULL) {
421		sbuf_printf(sb, "%s<failprob>%u</failprob>\n", indent,
422		    pp->index);
423	}
424}
425
426DECLARE_GEOM_CLASS(g_nop_class, g_nop);
427