xref: /freebsd/sys/geom/geom.h (revision 43764a7ffa9ad6eba3275410bc2397d3d398f75f)
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 #ifndef _GEOM_GEOM_H_
39 #define _GEOM_GEOM_H_
40 
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/sx.h>
44 #include <sys/queue.h>
45 #include <sys/ioccom.h>
46 #include <sys/conf.h>
47 #include <sys/sbuf.h>
48 #include <sys/module.h>
49 
50 struct g_class;
51 struct g_geom;
52 struct g_consumer;
53 struct g_provider;
54 struct g_stat;
55 struct thread;
56 struct bio;
57 struct sbuf;
58 struct gctl_req;
59 struct g_configargs;
60 
61 typedef int g_config_t (struct g_configargs *ca);
62 typedef void g_ctl_req_t (struct gctl_req *, struct g_class *cp, char const *verb);
63 typedef int g_ctl_create_geom_t (struct gctl_req *, struct g_class *cp, struct g_provider *pp);
64 typedef int g_ctl_destroy_geom_t (struct gctl_req *, struct g_class *cp, struct g_geom *gp);
65 typedef int g_ctl_config_geom_t (struct gctl_req *, struct g_geom *gp, const char *verb);
66 typedef void g_init_t (struct g_class *mp);
67 typedef void g_fini_t (struct g_class *mp);
68 typedef struct g_geom * g_taste_t (struct g_class *, struct g_provider *, int flags);
69 typedef int g_ioctl_t(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td);
70 #define G_TF_NORMAL		0
71 #define G_TF_INSIST		1
72 #define G_TF_TRANSPARENT	2
73 typedef int g_access_t (struct g_provider *, int, int, int);
74 /* XXX: not sure about the thread arg */
75 typedef void g_orphan_t (struct g_consumer *);
76 
77 typedef void g_start_t (struct bio *);
78 typedef void g_spoiled_t (struct g_consumer *);
79 typedef void g_attrchanged_t (struct g_consumer *, const char *attr);
80 typedef void g_dumpconf_t (struct sbuf *, const char *indent, struct g_geom *,
81     struct g_consumer *, struct g_provider *);
82 
83 /*
84  * The g_class structure describes a transformation class.  In other words
85  * all BSD disklabel handlers share one g_class, all MBR handlers share
86  * one common g_class and so on.
87  * Certain operations are instantiated on the class, most notably the
88  * taste and config_geom functions.
89  */
90 struct g_class {
91 	const char		*name;
92 	u_int			version;
93 	g_taste_t		*taste;
94 	g_config_t		*config;
95 	g_ctl_req_t		*ctlreq;
96 	g_init_t		*init;
97 	g_fini_t		*fini;
98 	g_ctl_destroy_geom_t	*destroy_geom;
99 	/*
100 	 * Default values for geom methods
101 	 */
102 	g_start_t		*start;
103 	g_spoiled_t		*spoiled;
104 	g_attrchanged_t		*attrchanged;
105 	g_dumpconf_t		*dumpconf;
106 	g_access_t		*access;
107 	g_orphan_t		*orphan;
108 	g_ioctl_t		*ioctl;
109 	/*
110 	 * The remaining elements are private
111 	 */
112 	LIST_ENTRY(g_class)	class;
113 	LIST_HEAD(,g_geom)	geom;
114 };
115 
116 #define G_VERSION_00	0x19950323
117 #define G_VERSION_01	0x20041207	/* add fflag to g_ioctl_t */
118 #define G_VERSION	G_VERSION_01
119 
120 /*
121  * The g_geom is an instance of a g_class.
122  */
123 struct g_geom {
124 	char			*name;
125 	struct g_class		*class;
126 	LIST_ENTRY(g_geom)	geom;
127 	LIST_HEAD(,g_consumer)	consumer;
128 	LIST_HEAD(,g_provider)	provider;
129 	TAILQ_ENTRY(g_geom)	geoms;	/* XXX: better name */
130 	int			rank;
131 	g_start_t		*start;
132 	g_spoiled_t		*spoiled;
133 	g_attrchanged_t		*attrchanged;
134 	g_dumpconf_t		*dumpconf;
135 	g_access_t		*access;
136 	g_orphan_t		*orphan;
137 	g_ioctl_t		*ioctl;
138 	void			*softc;
139 	unsigned		flags;
140 #define	G_GEOM_WITHER		1
141 #define	G_GEOM_VOLATILE_BIO	2
142 };
143 
144 /*
145  * The g_bioq is a queue of struct bio's.
146  * XXX: possibly collection point for statistics.
147  * XXX: should (possibly) be collapsed with sys/bio.h::bio_queue_head.
148  */
149 struct g_bioq {
150 	TAILQ_HEAD(, bio)	bio_queue;
151 	struct mtx		bio_queue_lock;
152 	int			bio_queue_length;
153 };
154 
155 /*
156  * A g_consumer is an attachment point for a g_provider.  One g_consumer
157  * can only be attached to one g_provider, but multiple g_consumers
158  * can be attached to one g_provider.
159  */
160 
161 struct g_consumer {
162 	struct g_geom		*geom;
163 	LIST_ENTRY(g_consumer)	consumer;
164 	struct g_provider	*provider;
165 	LIST_ENTRY(g_consumer)	consumers;	/* XXX: better name */
166 	int			acr, acw, ace;
167 	int			spoiled;
168 	struct devstat		*stat;
169 	u_int			nstart, nend;
170 
171 	/* Two fields for the implementing class to use */
172 	void			*private;
173 	u_int			index;
174 };
175 
176 /*
177  * A g_provider is a "logical disk".
178  */
179 struct g_provider {
180 	char			*name;
181 	LIST_ENTRY(g_provider)	provider;
182 	struct g_geom		*geom;
183 	LIST_HEAD(,g_consumer)	consumers;
184 	int			acr, acw, ace;
185 	int			error;
186 	TAILQ_ENTRY(g_provider)	orphan;
187 	off_t			mediasize;
188 	u_int			sectorsize;
189 	u_int			stripesize;
190 	u_int			stripeoffset;
191 	struct devstat		*stat;
192 	u_int			nstart, nend;
193 	u_int			flags;
194 #define G_PF_CANDELETE		0x1
195 #define G_PF_WITHER		0x2
196 #define G_PF_ORPHAN		0x4
197 
198 	/* Two fields for the implementing class to use */
199 	void			*private;
200 	u_int			index;
201 };
202 
203 /*
204  * Descriptor of a classifier. We can register a function and
205  * an argument, which is called by g_io_request() on bio's
206  * that are not previously classified.
207  */
208 struct g_classifier_hook {
209 	TAILQ_ENTRY(g_classifier_hook) link;
210 	int			(*func)(void *arg, struct bio *bp);
211 	void			*arg;
212 };
213 
214 /* BIO_GETATTR("GEOM::setstate") argument values. */
215 #define G_STATE_FAILED		0
216 #define G_STATE_REBUILD		1
217 #define G_STATE_RESYNC		2
218 #define G_STATE_ACTIVE		3
219 
220 /* geom_dev.c */
221 struct cdev;
222 void g_dev_print(void);
223 void g_dev_physpath_changed(void);
224 struct g_provider *g_dev_getprovider(struct cdev *dev);
225 
226 /* geom_dump.c */
227 void g_trace(int level, const char *, ...);
228 #	define G_T_TOPOLOGY	1
229 #	define G_T_BIO		2
230 #	define G_T_ACCESS	4
231 
232 
233 /* geom_event.c */
234 typedef void g_event_t(void *, int flag);
235 #define EV_CANCEL	1
236 int g_post_event(g_event_t *func, void *arg, int flag, ...);
237 int g_waitfor_event(g_event_t *func, void *arg, int flag, ...);
238 void g_cancel_event(void *ref);
239 int g_attr_changed(struct g_provider *pp, const char *attr, int flag);
240 void g_orphan_provider(struct g_provider *pp, int error);
241 void g_waitidlelock(void);
242 
243 /* geom_subr.c */
244 int g_access(struct g_consumer *cp, int nread, int nwrite, int nexcl);
245 int g_attach(struct g_consumer *cp, struct g_provider *pp);
246 int g_compare_names(const char *namea, const char *nameb);
247 void g_destroy_consumer(struct g_consumer *cp);
248 void g_destroy_geom(struct g_geom *pp);
249 void g_destroy_provider(struct g_provider *pp);
250 void g_detach(struct g_consumer *cp);
251 void g_error_provider(struct g_provider *pp, int error);
252 struct g_provider *g_provider_by_name(char const *arg);
253 int g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len);
254 #define g_getattr(a, c, v) g_getattr__((a), (c), (v), sizeof *(v))
255 int g_handleattr(struct bio *bp, const char *attribute, const void *val,
256     int len);
257 int g_handleattr_int(struct bio *bp, const char *attribute, int val);
258 int g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val);
259 int g_handleattr_str(struct bio *bp, const char *attribute, const char *str);
260 struct g_consumer * g_new_consumer(struct g_geom *gp);
261 struct g_geom * g_new_geomf(struct g_class *mp, const char *fmt, ...);
262 struct g_provider * g_new_providerf(struct g_geom *gp, const char *fmt, ...);
263 int g_retaste(struct g_class *mp);
264 void g_spoil(struct g_provider *pp, struct g_consumer *cp);
265 int g_std_access(struct g_provider *pp, int dr, int dw, int de);
266 void g_std_done(struct bio *bp);
267 void g_std_spoiled(struct g_consumer *cp);
268 void g_wither_geom(struct g_geom *gp, int error);
269 void g_wither_geom_close(struct g_geom *gp, int error);
270 void g_wither_provider(struct g_provider *pp, int error);
271 
272 #if defined(DIAGNOSTIC) || defined(DDB)
273 int g_valid_obj(void const *ptr);
274 #endif
275 #ifdef DIAGNOSTIC
276 #define G_VALID_CLASS(foo) \
277     KASSERT(g_valid_obj(foo) == 1, ("%p is not a g_class", foo))
278 #define G_VALID_GEOM(foo) \
279     KASSERT(g_valid_obj(foo) == 2, ("%p is not a g_geom", foo))
280 #define G_VALID_CONSUMER(foo) \
281     KASSERT(g_valid_obj(foo) == 3, ("%p is not a g_consumer", foo))
282 #define G_VALID_PROVIDER(foo) \
283     KASSERT(g_valid_obj(foo) == 4, ("%p is not a g_provider", foo))
284 #else
285 #define G_VALID_CLASS(foo) do { } while (0)
286 #define G_VALID_GEOM(foo) do { } while (0)
287 #define G_VALID_CONSUMER(foo) do { } while (0)
288 #define G_VALID_PROVIDER(foo) do { } while (0)
289 #endif
290 
291 int g_modevent(module_t, int, void *);
292 
293 /* geom_io.c */
294 struct bio * g_clone_bio(struct bio *);
295 struct bio * g_duplicate_bio(struct bio *);
296 void g_destroy_bio(struct bio *);
297 void g_io_deliver(struct bio *bp, int error);
298 int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr);
299 int g_io_flush(struct g_consumer *cp);
300 int g_register_classifier(struct g_classifier_hook *hook);
301 void g_unregister_classifier(struct g_classifier_hook *hook);
302 void g_io_request(struct bio *bp, struct g_consumer *cp);
303 struct bio *g_new_bio(void);
304 struct bio *g_alloc_bio(void);
305 void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
306 int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length);
307 int g_delete_data(struct g_consumer *cp, off_t offset, off_t length);
308 void g_print_bio(struct bio *bp);
309 
310 /* geom_kern.c / geom_kernsim.c */
311 
312 #ifdef _KERNEL
313 
314 extern struct sx topology_lock;
315 
316 struct g_kerneldump {
317 	off_t		offset;
318 	off_t		length;
319 	struct dumperinfo di;
320 };
321 
322 MALLOC_DECLARE(M_GEOM);
323 
324 static __inline void *
325 g_malloc(int size, int flags)
326 {
327 	void *p;
328 
329 	p = malloc(size, M_GEOM, flags);
330 	return (p);
331 }
332 
333 static __inline void
334 g_free(void *ptr)
335 {
336 
337 #ifdef DIAGNOSTIC
338 	if (sx_xlocked(&topology_lock)) {
339 		KASSERT(g_valid_obj(ptr) == 0,
340 		    ("g_free(%p) of live object, type %d", ptr,
341 		    g_valid_obj(ptr)));
342 	}
343 #endif
344 	free(ptr, M_GEOM);
345 }
346 
347 #define g_topology_lock() 					\
348 	do {							\
349 		mtx_assert(&Giant, MA_NOTOWNED);		\
350 		sx_xlock(&topology_lock);			\
351 	} while (0)
352 
353 #define g_topology_try_lock()	sx_try_xlock(&topology_lock)
354 
355 #define g_topology_unlock()					\
356 	do {							\
357 		sx_xunlock(&topology_lock);			\
358 	} while (0)
359 
360 #define g_topology_assert()					\
361 	do {							\
362 		sx_assert(&topology_lock, SX_XLOCKED);		\
363 	} while (0)
364 
365 #define g_topology_assert_not()					\
366 	do {							\
367 		sx_assert(&topology_lock, SX_UNLOCKED);		\
368 	} while (0)
369 
370 #define g_topology_sleep(chan, timo)				\
371 	sx_sleep(chan, &topology_lock, 0, "gtopol", timo)
372 
373 #define DECLARE_GEOM_CLASS(class, name) 			\
374 	static moduledata_t name##_mod = {			\
375 		#name, g_modevent, &class			\
376 	};							\
377 	DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
378 
379 #endif /* _KERNEL */
380 
381 /* geom_ctl.c */
382 int gctl_set_param(struct gctl_req *req, const char *param, void const *ptr, int len);
383 void gctl_set_param_err(struct gctl_req *req, const char *param, void const *ptr, int len);
384 void *gctl_get_param(struct gctl_req *req, const char *param, int *len);
385 char const *gctl_get_asciiparam(struct gctl_req *req, const char *param);
386 void *gctl_get_paraml(struct gctl_req *req, const char *param, int len);
387 int gctl_error(struct gctl_req *req, const char *fmt, ...) __printflike(2, 3);
388 struct g_class *gctl_get_class(struct gctl_req *req, char const *arg);
389 struct g_geom *gctl_get_geom(struct gctl_req *req, struct g_class *mpr, char const *arg);
390 struct g_provider *gctl_get_provider(struct gctl_req *req, char const *arg);
391 
392 #endif /* _GEOM_GEOM_H_ */
393