geom.h revision 136836
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: head/sys/geom/geom.h 136836 2004-10-23 20:22:02Z phk $
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
49struct g_class;
50struct g_geom;
51struct g_consumer;
52struct g_provider;
53struct g_stat;
54struct thread;
55struct bio;
56struct sbuf;
57struct gctl_req;
58struct g_configargs;
59
60typedef int g_config_t (struct g_configargs *ca);
61typedef void g_ctl_req_t (struct gctl_req *, struct g_class *cp, char const *verb);
62typedef int g_ctl_create_geom_t (struct gctl_req *, struct g_class *cp, struct g_provider *pp);
63typedef int g_ctl_destroy_geom_t (struct gctl_req *, struct g_class *cp, struct g_geom *gp);
64typedef int g_ctl_config_geom_t (struct gctl_req *, struct g_geom *gp, const char *verb);
65typedef void g_init_t (struct g_class *mp);
66typedef void g_fini_t (struct g_class *mp);
67typedef struct g_geom * g_taste_t (struct g_class *, struct g_provider *, int flags);
68typedef int g_ioctl_t(struct g_provider *pp, u_long cmd, void *data, struct thread *td);
69#define G_TF_NORMAL		0
70#define G_TF_INSIST		1
71#define G_TF_TRANSPARENT	2
72typedef int g_access_t (struct g_provider *, int, int, int);
73/* XXX: not sure about the thread arg */
74typedef void g_orphan_t (struct g_consumer *);
75
76typedef void g_start_t (struct bio *);
77typedef void g_spoiled_t (struct g_consumer *);
78typedef 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 */
88struct 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	 * Defaults 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	G_VERSION_00
115
116/*
117 * The g_geom is an instance of a g_class.
118 */
119struct g_geom {
120	char			*name;
121	struct g_class		*class;
122	LIST_ENTRY(g_geom)	geom;
123	LIST_HEAD(,g_consumer)	consumer;
124	LIST_HEAD(,g_provider)	provider;
125	TAILQ_ENTRY(g_geom)	geoms;	/* XXX: better name */
126	int			rank;
127	g_start_t		*start;
128	g_spoiled_t		*spoiled;
129	g_dumpconf_t		*dumpconf;
130	g_access_t		*access;
131	g_orphan_t		*orphan;
132	g_ioctl_t		*ioctl;
133	void			*softc;
134	unsigned		flags;
135#define	G_GEOM_WITHER		1
136};
137
138/*
139 * The g_bioq is a queue of struct bio's.
140 * XXX: possibly collection point for statistics.
141 * XXX: should (possibly) be collapsed with sys/bio.h::bio_queue_head.
142 */
143struct g_bioq {
144	TAILQ_HEAD(, bio)	bio_queue;
145	struct mtx		bio_queue_lock;
146	int			bio_queue_length;
147};
148
149/*
150 * A g_consumer is an attachment point for a g_provider.  One g_consumer
151 * can only be attached to one g_provider, but multiple g_consumers
152 * can be attached to one g_provider.
153 */
154
155struct g_consumer {
156	struct g_geom		*geom;
157	LIST_ENTRY(g_consumer)	consumer;
158	struct g_provider	*provider;
159	LIST_ENTRY(g_consumer)	consumers;	/* XXX: better name */
160	int			acr, acw, ace;
161	int			spoiled;
162	struct devstat		*stat;
163	u_int			nstart, nend;
164
165	/* Two fields for the implementing class to use */
166	void			*private;
167	u_int			index;
168};
169
170/*
171 * A g_provider is a "logical disk".
172 */
173struct g_provider {
174	char			*name;
175	LIST_ENTRY(g_provider)	provider;
176	struct g_geom		*geom;
177	LIST_HEAD(,g_consumer)	consumers;
178	int			acr, acw, ace;
179	int			error;
180	TAILQ_ENTRY(g_provider)	orphan;
181	off_t			mediasize;
182	u_int			sectorsize;
183	u_int			stripesize;
184	u_int			stripeoffset;
185	struct devstat		*stat;
186	u_int			nstart, nend;
187	u_int			flags;
188#define G_PF_CANDELETE		0x1
189#define G_PF_WITHER		0x2
190#define G_PF_ORPHAN		0x4
191
192	/* Two fields for the implementing class to use */
193	void			*private;
194	u_int			index;
195};
196
197/* geom_dev.c */
198struct cdev;
199void g_dev_print(void);
200struct g_provider *g_dev_getprovider(struct cdev *dev);
201
202/* geom_dump.c */
203void g_trace(int level, const char *, ...);
204#	define G_T_TOPOLOGY	1
205#	define G_T_BIO		2
206#	define G_T_ACCESS	4
207
208
209/* geom_event.c */
210typedef void g_event_t(void *, int flag);
211#define EV_CANCEL	1
212int g_post_event(g_event_t *func, void *arg, int flag, ...);
213int g_waitfor_event(g_event_t *func, void *arg, int flag, ...);
214void g_cancel_event(void *ref);
215void g_orphan_provider(struct g_provider *pp, int error);
216
217/* geom_subr.c */
218int g_access(struct g_consumer *cp, int nread, int nwrite, int nexcl);
219int g_attach(struct g_consumer *cp, struct g_provider *pp);
220void g_destroy_consumer(struct g_consumer *cp);
221void g_destroy_geom(struct g_geom *pp);
222void g_destroy_provider(struct g_provider *pp);
223void g_detach(struct g_consumer *cp);
224void g_error_provider(struct g_provider *pp, int error);
225struct g_provider *g_provider_by_name(char const *arg);
226int g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len);
227#define g_getattr(a, c, v) g_getattr__((a), (c), (v), sizeof *(v))
228int g_handleattr(struct bio *bp, const char *attribute, void *val, int len);
229int g_handleattr_int(struct bio *bp, const char *attribute, int val);
230int g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val);
231struct g_consumer * g_new_consumer(struct g_geom *gp);
232struct g_geom * g_new_geomf(struct g_class *mp, const char *fmt, ...);
233struct g_provider * g_new_providerf(struct g_geom *gp, const char *fmt, ...);
234void g_spoil(struct g_provider *pp, struct g_consumer *cp);
235int g_std_access(struct g_provider *pp, int dr, int dw, int de);
236void g_std_done(struct bio *bp);
237void g_std_spoiled(struct g_consumer *cp);
238void g_wither_geom(struct g_geom *gp, int error);
239
240#ifdef DIAGNOSTIC
241int g_valid_obj(void const *ptr);
242#define G_VALID_CLASS(foo) \
243    KASSERT(g_valid_obj(foo) == 1, ("%p is not a g_class", foo))
244#define G_VALID_GEOM(foo) \
245    KASSERT(g_valid_obj(foo) == 2, ("%p is not a g_geom", foo))
246#define G_VALID_CONSUMER(foo) \
247    KASSERT(g_valid_obj(foo) == 3, ("%p is not a g_consumer", foo))
248#define G_VALID_PROVIDER(foo) \
249    KASSERT(g_valid_obj(foo) == 4, ("%p is not a g_provider", foo))
250#else
251#define G_VALID_CLASS(foo) do { } while (0)
252#define G_VALID_GEOM(foo) do { } while (0)
253#define G_VALID_CONSUMER(foo) do { } while (0)
254#define G_VALID_PROVIDER(foo) do { } while (0)
255#endif
256
257int g_modevent(module_t, int, void *);
258
259/* geom_io.c */
260struct bio * g_clone_bio(struct bio *);
261void g_destroy_bio(struct bio *);
262void g_io_deliver(struct bio *bp, int error);
263int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr);
264void g_io_request(struct bio *bp, struct g_consumer *cp);
265struct bio *g_new_bio(void);
266struct bio *g_alloc_bio(void);
267void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
268int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length);
269void g_print_bio(struct bio *bp);
270
271/* geom_kern.c / geom_kernsim.c */
272
273#ifdef _KERNEL
274
275struct g_kerneldump {
276	off_t		offset;
277	off_t		length;
278};
279
280MALLOC_DECLARE(M_GEOM);
281
282static __inline void *
283g_malloc(int size, int flags)
284{
285	void *p;
286
287	p = malloc(size, M_GEOM, flags);
288	return (p);
289}
290
291static __inline void
292g_free(void *ptr)
293{
294
295#ifdef DIAGNOSTIC
296	KASSERT(g_valid_obj(ptr) == 0,
297	    ("g_free(%p) of live object, type %d", ptr, g_valid_obj(ptr)));
298#endif
299	free(ptr, M_GEOM);
300}
301
302extern struct sx topology_lock;
303
304#define g_topology_lock() 					\
305	do {							\
306		mtx_assert(&Giant, MA_NOTOWNED);		\
307		sx_xlock(&topology_lock);			\
308	} while (0)
309
310#define g_topology_unlock()					\
311	do {							\
312		sx_xunlock(&topology_lock);			\
313	} while (0)
314
315#define g_topology_assert()					\
316	do {							\
317		sx_assert(&topology_lock, SX_XLOCKED);		\
318	} while (0)
319
320#define g_topology_assert_not()					\
321	do {							\
322		sx_assert(&topology_lock, SX_UNLOCKED);		\
323	} while (0)
324
325#define DECLARE_GEOM_CLASS(class, name) 			\
326	static moduledata_t name##_mod = {			\
327		#name, g_modevent, &class			\
328	};							\
329	DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
330
331#endif /* _KERNEL */
332
333/* geom_ctl.c */
334void gctl_set_param(struct gctl_req *req, const char *param, void const *ptr, int len);
335void *gctl_get_param(struct gctl_req *req, const char *param, int *len);
336char const *gctl_get_asciiparam(struct gctl_req *req, const char *param);
337void *gctl_get_paraml(struct gctl_req *req, const char *param, int len);
338int gctl_error(struct gctl_req *req, const char *fmt, ...);
339struct g_class *gctl_get_class(struct gctl_req *req, char const *arg);
340struct g_geom *gctl_get_geom(struct gctl_req *req, struct g_class *mpr, char const *arg);
341struct g_provider *gctl_get_provider(struct gctl_req *req, char const *arg);
342
343#endif /* _GEOM_GEOM_H_ */
344