xref: /freebsd/sys/geom/geom.h (revision c11e094d96120a2e0e726ed9705ae0ec08db49b6)
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 
48 #ifdef KERNELSIM
49 /*
50  * The GEOM subsystem makes a few concessions in order to be able to run as a
51  * user-land simulation as well as a kernel component.
52  */
53 #include <geom_sim.h>
54 #endif
55 
56 struct g_class;
57 struct g_geom;
58 struct g_consumer;
59 struct g_provider;
60 struct g_event;
61 struct thread;
62 struct bio;
63 struct sbuf;
64 
65 
66 typedef struct g_geom * g_create_geom_t (struct g_class *mp,
67     struct g_provider *pp, char *name);
68 typedef struct g_geom * g_taste_t (struct g_class *, struct g_provider *,
69     int flags);
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_dumpconf_t (struct sbuf *, char *indent, struct g_geom *,
80     struct g_consumer *, struct g_provider *);
81 
82 /*
83  * The g_class structure describes a transformation class.  In other words
84  * all BSD disklabel handlers share one g_class, all MBR handlers share
85  * one common g_class and so on.
86  * Certain operations are instantiated on the class, most notably the
87  * taste and create_geom functions.
88  */
89 struct g_class {
90 	char			*name;
91 	g_taste_t		*taste;
92 	g_create_geom_t		*create_geom;
93 	/*
94 	 * The remaning elements are private and classes should use
95 	 * the G_CLASS_INITSTUFF macro to initialize them.
96          */
97 	LIST_ENTRY(g_class)	class;
98 	LIST_HEAD(,g_geom)	geom;
99 	struct g_event		*event;
100 	u_int			protect;
101 };
102 
103 #define G_CLASS_INITSTUFF { 0, 0 }, { 0 }, 0, 0
104 
105 /*
106  * The g_geom is an instance of a g_class.
107  */
108 struct g_geom {
109 	u_int			protect;
110 	char			*name;
111 	struct g_class		*class;
112 	LIST_ENTRY(g_geom)	geom;
113 	LIST_HEAD(,g_consumer)	consumer;
114 	LIST_HEAD(,g_provider)	provider;
115 	TAILQ_ENTRY(g_geom)	geoms;	/* XXX: better name */
116 	int			rank;
117 	g_start_t		*start;
118 	g_spoiled_t		*spoiled;
119 	g_dumpconf_t		*dumpconf;
120 	g_access_t		*access;
121 	g_orphan_t		*orphan;
122 	void			*softc;
123 	struct g_event		*event;
124 	unsigned		flags;
125 #define	G_GEOM_WITHER		1
126 };
127 
128 /*
129  * The g_bioq is a queue of struct bio's.
130  * XXX: possibly collection point for statistics.
131  * XXX: should (possibly) be collapsed with sys/bio.h::bio_queue_head.
132  */
133 struct g_bioq {
134 	TAILQ_HEAD(, bio)	bio_queue;
135 	struct mtx		bio_queue_lock;
136 	int			bio_queue_length;
137 };
138 
139 /*
140  * A g_consumer is an attachment point for a g_provider.  One g_consumer
141  * can only be attached to one g_provider, but multiple g_consumers
142  * can be attached to one g_provider.
143  */
144 
145 struct g_consumer {
146 	u_int			protect;
147 	struct g_geom		*geom;
148 	LIST_ENTRY(g_consumer)	consumer;
149 	struct g_provider	*provider;
150 	LIST_ENTRY(g_consumer)	consumers;	/* XXX: better name */
151 	int			acr, acw, ace;
152 	struct g_event		*event;
153 
154 	int			biocount;
155 	int			spoiled;
156 };
157 
158 /*
159  * A g_provider is a "logical disk".
160  */
161 struct g_provider {
162 	u_int			protect;
163 	char			*name;
164 	LIST_ENTRY(g_provider)	provider;
165 	struct g_geom		*geom;
166 	LIST_HEAD(,g_consumer)	consumers;
167 	int			acr, acw, ace;
168 	int			error;
169 	struct g_event		*event;
170 	TAILQ_ENTRY(g_provider)	orphan;
171 	int			index;
172 	off_t			mediasize;
173 };
174 
175 /* geom_dump.c */
176 void g_hexdump(void *ptr, int length);
177 void g_trace(int level, char *, ...);
178 #	define G_T_TOPOLOGY	1
179 #	define G_T_BIO		2
180 #	define G_T_ACCESS	4
181 
182 /* geom_enc.c */
183 uint32_t g_dec_be2(u_char *p);
184 uint32_t g_dec_be4(u_char *p);
185 uint32_t g_dec_le2(u_char *p);
186 uint32_t g_dec_le4(u_char *p);
187 void g_enc_le4(u_char *p, uint32_t u);
188 
189 /* geom_event.c */
190 void g_orphan_provider(struct g_provider *pp, int error);
191 void g_rattle(void);
192 void g_silence(void);
193 
194 /* geom_subr.c */
195 int g_access_abs(struct g_consumer *cp, int read, int write, int exclusive);
196 int g_access_rel(struct g_consumer *cp, int read, int write, int exclusive);
197 void g_add_class(struct g_class *mp);
198 int g_attach(struct g_consumer *cp, struct g_provider *pp);
199 struct g_geom *g_create_geomf(char *class, struct g_provider *, char *fmt, ...);
200 void g_destroy_consumer(struct g_consumer *cp);
201 void g_destroy_geom(struct g_geom *pp);
202 void g_destroy_provider(struct g_provider *pp);
203 void g_dettach(struct g_consumer *cp);
204 void g_error_provider(struct g_provider *pp, int error);
205 int g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len);
206 #define g_getattr(a, c, v) g_getattr__((a), (c), (v), sizeof *(v))
207 int g_haveattr(struct bio *bp, char *attribute, void *val, int len);
208 int g_haveattr_int(struct bio *bp, char *attribute, int val);
209 int g_haveattr_off_t(struct bio *bp, char *attribute, off_t val);
210 struct g_geom * g_insert_geom(char *class, struct g_consumer *cp);
211 struct g_consumer * g_new_consumer(struct g_geom *gp);
212 struct g_geom * g_new_geomf(struct g_class *mp, char *fmt, ...);
213 struct g_provider * g_new_providerf(struct g_geom *gp, char *fmt, ...);
214 void g_sanity(void *ptr);
215 void g_spoil(struct g_provider *pp, struct g_consumer *cp);
216 int g_std_access(struct g_provider *pp, int dr, int dw, int de);
217 void g_std_done(struct bio *bp);
218 void g_std_spoiled(struct g_consumer *cp);
219 
220 /* geom_io.c */
221 struct bio * g_clone_bio(struct bio *);
222 void g_destroy_bio(struct bio *);
223 void g_io_deliver(struct bio *bp);
224 void g_io_fail(struct bio *bp, int error);
225 int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr);
226 void g_io_request(struct bio *bp, struct g_consumer *cp);
227 int g_io_setattr(const char *attr, struct g_consumer *cp, int len, void *ptr);
228 struct bio *g_new_bio(void);
229 void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
230 
231 /* geom_kern.c / geom_kernsim.c */
232 
233 struct g_ioctl {
234 	u_long		cmd;
235 	void		*data;
236 	int		fflag;
237 	struct thread	*td;
238 };
239 
240 #ifdef _KERNEL
241 
242 struct g_kerneldump {
243 	off_t		offset;
244 	off_t		length;
245 };
246 
247 MALLOC_DECLARE(M_GEOM);
248 
249 static __inline void *
250 g_malloc(int size, int flags)
251 {
252 	void *p;
253 
254 	mtx_lock(&Giant);
255 	p = malloc(size, M_GEOM, flags);
256 	mtx_unlock(&Giant);
257 	g_sanity(p);
258 	/* printf("malloc(%d, %x) -> %p\n", size, flags, p); */
259 	return (p);
260 }
261 
262 static __inline void
263 g_free(void *ptr)
264 {
265 	g_sanity(ptr);
266 	/* printf("free(%p)\n", ptr); */
267 	mtx_lock(&Giant);
268 	free(ptr, M_GEOM);
269 	mtx_unlock(&Giant);
270 }
271 
272 extern struct sx topology_lock;
273 #define g_topology_lock() do { mtx_assert(&Giant, MA_NOTOWNED); sx_xlock(&topology_lock); } while (0)
274 #define g_topology_unlock() do { g_sanity(NULL); sx_xunlock(&topology_lock); } while (0)
275 #define g_topology_assert() do { g_sanity(NULL); sx_assert(&topology_lock, SX_XLOCKED); } while (0)
276 
277 #define DECLARE_GEOM_CLASS(class, name) 	\
278 	static void				\
279 	name##init(void)			\
280 	{					\
281 		mtx_unlock(&Giant);		\
282 		g_add_class(&class);		\
283 		mtx_lock(&Giant);		\
284 	}					\
285 	SYSINIT(name, SI_SUB_PSEUDO, SI_ORDER_FIRST, name##init, NULL);
286 
287 #endif /* _KERNEL */
288 
289 #define GEOMGETCONF _IOWR('G',  0, struct sbuf)
290 
291 #endif /* _GEOM_GEOM_H_ */
292