xref: /freebsd/sys/geom/geom.h (revision 6780ab54325a71e7e70112b11657973edde8655e)
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 struct g_configargs;
65 
66 typedef int g_config_t (struct g_configargs *ca);
67 typedef struct g_geom * g_taste_t (struct g_class *, struct g_provider *,
68     int flags);
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 	g_taste_t		*taste;
91 	g_config_t		*config;
92 	/*
93 	 * The remaning elements are private and classes should use
94 	 * the G_CLASS_INITIALIZER macro to initialize them.
95          */
96 	LIST_ENTRY(g_class)	class;
97 	LIST_HEAD(,g_geom)	geom;
98 	struct g_event		*event;
99 	u_int			protect;
100 };
101 
102 #define G_CLASS_INITIALIZER { 0, 0 }, { 0 }, 0, 0
103 
104 /*
105  * The g_geom is an instance of a g_class.
106  */
107 struct g_geom {
108 	u_int			protect;
109 	char			*name;
110 	struct g_class		*class;
111 	LIST_ENTRY(g_geom)	geom;
112 	LIST_HEAD(,g_consumer)	consumer;
113 	LIST_HEAD(,g_provider)	provider;
114 	TAILQ_ENTRY(g_geom)	geoms;	/* XXX: better name */
115 	int			rank;
116 	g_start_t		*start;
117 	g_spoiled_t		*spoiled;
118 	g_dumpconf_t		*dumpconf;
119 	g_access_t		*access;
120 	g_orphan_t		*orphan;
121 	void			*softc;
122 	struct g_event		*event;
123 	unsigned		flags;
124 #define	G_GEOM_WITHER		1
125 };
126 
127 /*
128  * The g_bioq is a queue of struct bio's.
129  * XXX: possibly collection point for statistics.
130  * XXX: should (possibly) be collapsed with sys/bio.h::bio_queue_head.
131  */
132 struct g_bioq {
133 	TAILQ_HEAD(, bio)	bio_queue;
134 	struct mtx		bio_queue_lock;
135 	int			bio_queue_length;
136 };
137 
138 /*
139  * A g_consumer is an attachment point for a g_provider.  One g_consumer
140  * can only be attached to one g_provider, but multiple g_consumers
141  * can be attached to one g_provider.
142  */
143 
144 struct g_consumer {
145 	u_int			protect;
146 	struct g_geom		*geom;
147 	LIST_ENTRY(g_consumer)	consumer;
148 	struct g_provider	*provider;
149 	LIST_ENTRY(g_consumer)	consumers;	/* XXX: better name */
150 	int			acr, acw, ace;
151 	struct g_event		*event;
152 
153 	int			biocount;
154 	int			spoiled;
155 };
156 
157 /*
158  * A g_provider is a "logical disk".
159  */
160 struct g_provider {
161 	u_int			protect;
162 	char			*name;
163 	LIST_ENTRY(g_provider)	provider;
164 	struct g_geom		*geom;
165 	LIST_HEAD(,g_consumer)	consumers;
166 	int			acr, acw, ace;
167 	int			error;
168 	struct g_event		*event;
169 	TAILQ_ENTRY(g_provider)	orphan;
170 	u_int			index;
171 	off_t			mediasize;
172 	u_int			sectorsize;
173 };
174 
175 /*
176  * This gadget is used by userland to pinpoint a particular instance of
177  * something in the kernel.  The name is unreadable on purpose, people
178  * should not encounter it directly but use library functions to deal
179  * with it.
180  * If len is zero, "id" contains a cast of the kernel pointer where the
181  * entity is located, (likely derived from the "id=" attribute in the
182  * XML config) and the g_id*() functions will validate this before allowing
183  * it to be used.
184  * If len is non-zero, it is the strlen() of the name which is pointed to
185  * by "name".
186  */
187 struct geomidorname {
188 	u_int len;
189 	union {
190 		const char	*name;
191 		uintptr_t	id;
192 	} u;
193 };
194 
195 /* geom_dev.c */
196 int g_dev_print(void);
197 
198 /* geom_dump.c */
199 void g_hexdump(void *ptr, int length);
200 void g_trace(int level, const char *, ...);
201 #	define G_T_TOPOLOGY	1
202 #	define G_T_BIO		2
203 #	define G_T_ACCESS	4
204 
205 
206 /* geom_event.c */
207 typedef void g_call_me_t(void *);
208 int g_call_me(g_call_me_t *func, void *arg);
209 void g_orphan_provider(struct g_provider *pp, int error);
210 void g_waitidle(void);
211 
212 /* geom_subr.c */
213 int g_access_abs(struct g_consumer *cp, int nread, int nwrite, int nexcl);
214 int g_access_rel(struct g_consumer *cp, int nread, int nwrite, int nexcl);
215 void g_add_class(struct g_class *mp);
216 int g_attach(struct g_consumer *cp, struct g_provider *pp);
217 void g_destroy_consumer(struct g_consumer *cp);
218 void g_destroy_geom(struct g_geom *pp);
219 void g_destroy_provider(struct g_provider *pp);
220 void g_detach(struct g_consumer *cp);
221 void g_error_provider(struct g_provider *pp, int error);
222 int g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len);
223 #define g_getattr(a, c, v) g_getattr__((a), (c), (v), sizeof *(v))
224 int g_handleattr(struct bio *bp, const char *attribute, void *val, int len);
225 int g_handleattr_int(struct bio *bp, const char *attribute, int val);
226 int g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val);
227 struct g_geom * g_insert_geom(const char *class, struct g_consumer *cp);
228 struct g_consumer * g_new_consumer(struct g_geom *gp);
229 struct g_geom * g_new_geomf(struct g_class *mp, const char *fmt, ...);
230 struct g_provider * g_new_providerf(struct g_geom *gp, const char *fmt, ...);
231 void g_sanity(void *ptr);
232 void g_spoil(struct g_provider *pp, struct g_consumer *cp);
233 int g_std_access(struct g_provider *pp, int dr, int dw, int de);
234 void g_std_done(struct bio *bp);
235 void g_std_spoiled(struct g_consumer *cp);
236 struct g_class *g_idclass(struct geomidorname *);
237 struct g_geom *g_idgeom(struct geomidorname *);
238 struct g_provider *g_idprovider(struct geomidorname *);
239 
240 
241 /* geom_io.c */
242 struct bio * g_clone_bio(struct bio *);
243 void g_destroy_bio(struct bio *);
244 void g_io_deliver(struct bio *bp, int error);
245 int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr);
246 void g_io_request(struct bio *bp, struct g_consumer *cp);
247 int g_io_setattr(const char *attr, struct g_consumer *cp, int len, void *ptr);
248 struct bio *g_new_bio(void);
249 void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
250 int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length);
251 
252 /* geom_kern.c / geom_kernsim.c */
253 
254 #ifndef _SYS_CONF_H_
255 typedef int d_ioctl_t(dev_t dev, u_long cmd, caddr_t data,
256 		      int fflag, struct thread *td);
257 #endif
258 
259 struct g_ioctl {
260 	u_long		cmd;
261 	void		*data;
262 	int		fflag;
263 	struct thread	*td;
264 	d_ioctl_t	*func;
265 	void		*dev;
266 };
267 
268 #ifdef _KERNEL
269 
270 struct g_kerneldump {
271 	off_t		offset;
272 	off_t		length;
273 };
274 
275 MALLOC_DECLARE(M_GEOM);
276 
277 static __inline void *
278 g_malloc(int size, int flags)
279 {
280 	void *p;
281 
282 	p = malloc(size, M_GEOM, flags);
283 	g_sanity(p);
284 	/* printf("malloc(%d, %x) -> %p\n", size, flags, p); */
285 	return (p);
286 }
287 
288 static __inline void
289 g_free(void *ptr)
290 {
291 	g_sanity(ptr);
292 	/* printf("free(%p)\n", ptr); */
293 	free(ptr, M_GEOM);
294 }
295 
296 extern struct sx topology_lock;
297 
298 #define g_topology_lock() 					\
299 	do {							\
300 		mtx_assert(&Giant, MA_NOTOWNED);		\
301 		sx_xlock(&topology_lock);			\
302 	} while (0)
303 
304 #define g_topology_unlock()					\
305 	do {							\
306 		g_sanity(NULL);					\
307 		sx_xunlock(&topology_lock);			\
308 	} while (0)
309 
310 #define g_topology_assert()					\
311 	do {							\
312 		g_sanity(NULL);					\
313 		sx_assert(&topology_lock, SX_XLOCKED);		\
314 	} while (0)
315 
316 #define DECLARE_GEOM_CLASS_INIT(class, name, init) 	\
317 	SYSINIT(name, SI_SUB_DRIVERS, SI_ORDER_FIRST, init, NULL);
318 
319 #define DECLARE_GEOM_CLASS(class, name) 	\
320 	static void				\
321 	name##init(void)			\
322 	{					\
323 		mtx_unlock(&Giant);		\
324 		g_add_class(&class);		\
325 		mtx_lock(&Giant);		\
326 	}					\
327 	DECLARE_GEOM_CLASS_INIT(class, name, name##init);
328 
329 #endif /* _KERNEL */
330 
331 /*
332  * IOCTLS for talking to the geom.ctl device.
333  */
334 
335 /*
336  * This is the structure used internally in the kernel, it is created and
337  * populated by geom_ctl.c.
338  */
339 struct g_configargs {
340 	/* Valid on call */
341 	struct g_class		*class;
342 	struct g_geom		*geom;
343 	struct g_provider	*provider;
344 	u_int			flag;
345 	u_int			len;
346 	void			*ptr;
347 };
348 
349 /*
350  * This is the structure used to communicate with userland.
351  */
352 struct geomconfiggeom {
353 	/* Valid on call */
354 	struct geomidorname	class;
355 	struct geomidorname	geom;
356 	struct geomidorname	provider;
357 	u_int			flag;
358 	u_int			len;
359 	void			*ptr;
360 };
361 
362 #define GEOMCONFIGGEOM _IOW('G',  0, struct geomconfiggeom)
363 
364 #define GCFG_GENERIC0		0x00000000
365 	/*
366 	 * Generic requests suitable for all classes.
367 	 */
368 #define GCFG_CLASS0		0x10000000
369 	/*
370 	 * Class specific verbs.  Allocations in this part of the numberspace
371 	 * can only be done after review and approval of phk@FreeBSD.org.
372 	 * All allocations in this space will be listed in this file.
373 	 */
374 #define GCFG_PRIVATE0		0x20000000
375 	/*
376 	 * Lowest allocation for private flag definitions.
377 	 * If you define you own private "verbs", please express them in
378 	 * your code as (GCFG_PRIVATE0 + somenumber), where somenumber is
379 	 * a magic number in the range [0x0 ... 0xfffffff] chosen the way
380 	 * magic numbers are chosen.  Such allocation SHALL NOT be listed
381 	 * here but SHOULD be listed in some suitable .h file.
382 	 */
383 #define GCFG_RESERVED0		0x30000000
384 #define GCFG_RESERVEDN		0xffffffff
385 	/*
386 	 * This area is reserved for the future.
387 	 */
388 
389 #define GCFG_CREATE		(GCFG_GENERIC0 + 0x0)
390 	/*
391 	 * Request geom construction.
392 	 * ptr/len is class-specific.
393 	 */
394 #define GCFG_DISMANTLE		(GCFG_GENERIC0 + 0x1)
395 	/*
396 	 * Request orderly geom dismantling.
397 	 * ptr/len is class-specific.
398 	 */
399 
400 
401 struct gcfg_magicrw {
402 	off_t	offset;
403 	u_int	len;
404 };
405 
406 #define GCFG_MAGICREAD		(GCFG_GENERIC0 + 0x100)
407 	/*
408 	 * Read of magic spaces.
409 	 * ptr/len is gcfgmagicrw structure followed by bufferspace
410 	 * for data to be read.
411 	 */
412 #define GCFG_MAGICWRITE		(GCFG_GENERIC0 + 0x101)
413 	/*
414 	 * Write of magic spaces.
415 	 * as above, only the other way.
416 	 */
417 
418 
419 /* geom_enc.c */
420 uint16_t g_dec_be2(const u_char *p);
421 uint32_t g_dec_be4(const u_char *p);
422 uint16_t g_dec_le2(const u_char *p);
423 uint32_t g_dec_le4(const u_char *p);
424 uint64_t g_dec_le8(const u_char *p);
425 void g_enc_le2(u_char *p, uint16_t u);
426 void g_enc_le4(u_char *p, uint32_t u);
427 void g_enc_le8(u_char *p, uint64_t u);
428 
429 #endif /* _GEOM_GEOM_H_ */
430