xref: /freebsd/sys/geom/geom.h (revision 7aa383846770374466b1dcb2cefd71bde9acf463)
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/sbuf.h>
47 #include <sys/module.h>
48 
49 struct g_class;
50 struct g_geom;
51 struct g_consumer;
52 struct g_provider;
53 struct g_stat;
54 struct thread;
55 struct bio;
56 struct sbuf;
57 struct gctl_req;
58 struct g_configargs;
59 
60 typedef int g_config_t (struct g_configargs *ca);
61 typedef void g_ctl_req_t (struct gctl_req *, struct g_class *cp, char const *verb);
62 typedef int g_ctl_create_geom_t (struct gctl_req *, struct g_class *cp, struct g_provider *pp);
63 typedef int g_ctl_destroy_geom_t (struct gctl_req *, struct g_class *cp, struct g_geom *gp);
64 typedef int g_ctl_config_geom_t (struct gctl_req *, struct g_geom *gp, const char *verb);
65 typedef void g_init_t (struct g_class *mp);
66 typedef void g_fini_t (struct g_class *mp);
67 typedef struct g_geom * g_taste_t (struct g_class *, struct g_provider *, int flags);
68 typedef int g_ioctl_t(struct g_provider *pp, u_long cmd, void *data, int fflag, struct thread *td);
69 #define G_TF_NORMAL		0
70 #define G_TF_INSIST		1
71 #define G_TF_TRANSPARENT	2
72 typedef int g_access_t (struct g_provider *, int, int, int);
73 /* XXX: not sure about the thread arg */
74 typedef void g_orphan_t (struct g_consumer *);
75 
76 typedef void g_start_t (struct bio *);
77 typedef void g_spoiled_t (struct g_consumer *);
78 typedef void g_dumpconf_t (struct sbuf *, const char *indent, struct g_geom *,
79     struct g_consumer *, struct g_provider *);
80 
81 /*
82  * The g_class structure describes a transformation class.  In other words
83  * all BSD disklabel handlers share one g_class, all MBR handlers share
84  * one common g_class and so on.
85  * Certain operations are instantiated on the class, most notably the
86  * taste and config_geom functions.
87  */
88 struct g_class {
89 	const char		*name;
90 	u_int			version;
91 	g_taste_t		*taste;
92 	g_config_t		*config;
93 	g_ctl_req_t		*ctlreq;
94 	g_init_t		*init;
95 	g_fini_t		*fini;
96 	g_ctl_destroy_geom_t	*destroy_geom;
97 	/*
98 	 * Default values for geom methods
99 	 */
100 	g_start_t		*start;
101 	g_spoiled_t		*spoiled;
102 	g_dumpconf_t		*dumpconf;
103 	g_access_t		*access;
104 	g_orphan_t		*orphan;
105 	g_ioctl_t		*ioctl;
106 	/*
107 	 * The remaining elements are private
108 	 */
109 	LIST_ENTRY(g_class)	class;
110 	LIST_HEAD(,g_geom)	geom;
111 };
112 
113 #define G_VERSION_00	0x19950323
114 #define G_VERSION_01	0x20041207	/* add fflag to g_ioctl_t */
115 #define G_VERSION	G_VERSION_01
116 
117 /*
118  * The g_geom is an instance of a g_class.
119  */
120 struct g_geom {
121 	char			*name;
122 	struct g_class		*class;
123 	LIST_ENTRY(g_geom)	geom;
124 	LIST_HEAD(,g_consumer)	consumer;
125 	LIST_HEAD(,g_provider)	provider;
126 	TAILQ_ENTRY(g_geom)	geoms;	/* XXX: better name */
127 	int			rank;
128 	g_start_t		*start;
129 	g_spoiled_t		*spoiled;
130 	g_dumpconf_t		*dumpconf;
131 	g_access_t		*access;
132 	g_orphan_t		*orphan;
133 	g_ioctl_t		*ioctl;
134 	void			*softc;
135 	unsigned		flags;
136 #define	G_GEOM_WITHER		1
137 #define	G_GEOM_VOLATILE_BIO	2
138 };
139 
140 /*
141  * The g_bioq is a queue of struct bio's.
142  * XXX: possibly collection point for statistics.
143  * XXX: should (possibly) be collapsed with sys/bio.h::bio_queue_head.
144  */
145 struct g_bioq {
146 	TAILQ_HEAD(, bio)	bio_queue;
147 	struct mtx		bio_queue_lock;
148 	int			bio_queue_length;
149 };
150 
151 /*
152  * A g_consumer is an attachment point for a g_provider.  One g_consumer
153  * can only be attached to one g_provider, but multiple g_consumers
154  * can be attached to one g_provider.
155  */
156 
157 struct g_consumer {
158 	struct g_geom		*geom;
159 	LIST_ENTRY(g_consumer)	consumer;
160 	struct g_provider	*provider;
161 	LIST_ENTRY(g_consumer)	consumers;	/* XXX: better name */
162 	int			acr, acw, ace;
163 	int			spoiled;
164 	struct devstat		*stat;
165 	u_int			nstart, nend;
166 
167 	/* Two fields for the implementing class to use */
168 	void			*private;
169 	u_int			index;
170 };
171 
172 /*
173  * A g_provider is a "logical disk".
174  */
175 struct g_provider {
176 	char			*name;
177 	LIST_ENTRY(g_provider)	provider;
178 	struct g_geom		*geom;
179 	LIST_HEAD(,g_consumer)	consumers;
180 	int			acr, acw, ace;
181 	int			error;
182 	TAILQ_ENTRY(g_provider)	orphan;
183 	off_t			mediasize;
184 	u_int			sectorsize;
185 	u_int			stripesize;
186 	u_int			stripeoffset;
187 	struct devstat		*stat;
188 	u_int			nstart, nend;
189 	u_int			flags;
190 #define G_PF_CANDELETE		0x1
191 #define G_PF_WITHER		0x2
192 #define G_PF_ORPHAN		0x4
193 
194 	/* Two fields for the implementing class to use */
195 	void			*private;
196 	u_int			index;
197 };
198 
199 /*
200  * Descriptor of a classifier. We can register a function and
201  * an argument, which is called by g_io_request() on bio's
202  * that are not previously classified.
203  */
204 struct g_classifier_hook {
205 	TAILQ_ENTRY(g_classifier_hook) link;
206 	int			(*func)(void *arg, struct bio *bp);
207 	void			*arg;
208 };
209 
210 /* geom_dev.c */
211 struct cdev;
212 void g_dev_print(void);
213 struct g_provider *g_dev_getprovider(struct cdev *dev);
214 
215 /* geom_dump.c */
216 void g_trace(int level, const char *, ...);
217 #	define G_T_TOPOLOGY	1
218 #	define G_T_BIO		2
219 #	define G_T_ACCESS	4
220 
221 
222 /* geom_event.c */
223 typedef void g_event_t(void *, int flag);
224 #define EV_CANCEL	1
225 int g_post_event(g_event_t *func, void *arg, int flag, ...);
226 int g_waitfor_event(g_event_t *func, void *arg, int flag, ...);
227 void g_cancel_event(void *ref);
228 void g_orphan_provider(struct g_provider *pp, int error);
229 void g_waitidlelock(void);
230 
231 /* geom_subr.c */
232 int g_access(struct g_consumer *cp, int nread, int nwrite, int nexcl);
233 int g_attach(struct g_consumer *cp, struct g_provider *pp);
234 void g_destroy_consumer(struct g_consumer *cp);
235 void g_destroy_geom(struct g_geom *pp);
236 void g_destroy_provider(struct g_provider *pp);
237 void g_detach(struct g_consumer *cp);
238 void g_error_provider(struct g_provider *pp, int error);
239 struct g_provider *g_provider_by_name(char const *arg);
240 int g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len);
241 #define g_getattr(a, c, v) g_getattr__((a), (c), (v), sizeof *(v))
242 int g_handleattr(struct bio *bp, const char *attribute, const void *val,
243     int len);
244 int g_handleattr_int(struct bio *bp, const char *attribute, int val);
245 int g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val);
246 int g_handleattr_str(struct bio *bp, const char *attribute, const char *str);
247 struct g_consumer * g_new_consumer(struct g_geom *gp);
248 struct g_geom * g_new_geomf(struct g_class *mp, const char *fmt, ...);
249 struct g_provider * g_new_providerf(struct g_geom *gp, const char *fmt, ...);
250 int g_retaste(struct g_class *mp);
251 void g_spoil(struct g_provider *pp, struct g_consumer *cp);
252 int g_std_access(struct g_provider *pp, int dr, int dw, int de);
253 void g_std_done(struct bio *bp);
254 void g_std_spoiled(struct g_consumer *cp);
255 void g_wither_geom(struct g_geom *gp, int error);
256 void g_wither_geom_close(struct g_geom *gp, int error);
257 void g_wither_provider(struct g_provider *pp, int error);
258 
259 #if defined(DIAGNOSTIC) || defined(DDB)
260 int g_valid_obj(void const *ptr);
261 #endif
262 #ifdef DIAGNOSTIC
263 #define G_VALID_CLASS(foo) \
264     KASSERT(g_valid_obj(foo) == 1, ("%p is not a g_class", foo))
265 #define G_VALID_GEOM(foo) \
266     KASSERT(g_valid_obj(foo) == 2, ("%p is not a g_geom", foo))
267 #define G_VALID_CONSUMER(foo) \
268     KASSERT(g_valid_obj(foo) == 3, ("%p is not a g_consumer", foo))
269 #define G_VALID_PROVIDER(foo) \
270     KASSERT(g_valid_obj(foo) == 4, ("%p is not a g_provider", foo))
271 #else
272 #define G_VALID_CLASS(foo) do { } while (0)
273 #define G_VALID_GEOM(foo) do { } while (0)
274 #define G_VALID_CONSUMER(foo) do { } while (0)
275 #define G_VALID_PROVIDER(foo) do { } while (0)
276 #endif
277 
278 int g_modevent(module_t, int, void *);
279 
280 /* geom_io.c */
281 struct bio * g_clone_bio(struct bio *);
282 struct bio * g_duplicate_bio(struct bio *);
283 void g_destroy_bio(struct bio *);
284 void g_io_deliver(struct bio *bp, int error);
285 int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr);
286 int g_io_flush(struct g_consumer *cp);
287 int g_register_classifier(struct g_classifier_hook *hook);
288 void g_unregister_classifier(struct g_classifier_hook *hook);
289 void g_io_request(struct bio *bp, struct g_consumer *cp);
290 struct bio *g_new_bio(void);
291 struct bio *g_alloc_bio(void);
292 void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
293 int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length);
294 int g_delete_data(struct g_consumer *cp, off_t offset, off_t length);
295 void g_print_bio(struct bio *bp);
296 
297 /* geom_kern.c / geom_kernsim.c */
298 
299 #ifdef _KERNEL
300 
301 extern struct sx topology_lock;
302 
303 struct g_kerneldump {
304 	off_t		offset;
305 	off_t		length;
306 };
307 
308 MALLOC_DECLARE(M_GEOM);
309 
310 static __inline void *
311 g_malloc(int size, int flags)
312 {
313 	void *p;
314 
315 	p = malloc(size, M_GEOM, flags);
316 	return (p);
317 }
318 
319 static __inline void
320 g_free(void *ptr)
321 {
322 
323 #ifdef DIAGNOSTIC
324 	if (sx_xlocked(&topology_lock)) {
325 		KASSERT(g_valid_obj(ptr) == 0,
326 		    ("g_free(%p) of live object, type %d", ptr,
327 		    g_valid_obj(ptr)));
328 	}
329 #endif
330 	free(ptr, M_GEOM);
331 }
332 
333 #define g_topology_lock() 					\
334 	do {							\
335 		mtx_assert(&Giant, MA_NOTOWNED);		\
336 		sx_xlock(&topology_lock);			\
337 	} while (0)
338 
339 #define g_topology_try_lock()	sx_try_xlock(&topology_lock)
340 
341 #define g_topology_unlock()					\
342 	do {							\
343 		sx_xunlock(&topology_lock);			\
344 	} while (0)
345 
346 #define g_topology_assert()					\
347 	do {							\
348 		sx_assert(&topology_lock, SX_XLOCKED);		\
349 	} while (0)
350 
351 #define g_topology_assert_not()					\
352 	do {							\
353 		sx_assert(&topology_lock, SX_UNLOCKED);		\
354 	} while (0)
355 
356 #define g_topology_sleep(chan, timo)				\
357 	sx_sleep(chan, &topology_lock, 0, "gtopol", timo)
358 
359 #define DECLARE_GEOM_CLASS(class, name) 			\
360 	static moduledata_t name##_mod = {			\
361 		#name, g_modevent, &class			\
362 	};							\
363 	DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
364 
365 #endif /* _KERNEL */
366 
367 /* geom_ctl.c */
368 int gctl_set_param(struct gctl_req *req, const char *param, void const *ptr, int len);
369 void gctl_set_param_err(struct gctl_req *req, const char *param, void const *ptr, int len);
370 void *gctl_get_param(struct gctl_req *req, const char *param, int *len);
371 char const *gctl_get_asciiparam(struct gctl_req *req, const char *param);
372 void *gctl_get_paraml(struct gctl_req *req, const char *param, int len);
373 int gctl_error(struct gctl_req *req, const char *fmt, ...) __printflike(2, 3);
374 struct g_class *gctl_get_class(struct gctl_req *req, char const *arg);
375 struct g_geom *gctl_get_geom(struct gctl_req *req, struct g_class *mpr, char const *arg);
376 struct g_provider *gctl_get_provider(struct gctl_req *req, char const *arg);
377 
378 #endif /* _GEOM_GEOM_H_ */
379