xref: /titanic_44/usr/src/lib/libzpool/common/sys/zfs_context.h (revision d583b39bfb4e2571d3e41097c5c357ffe353ad45)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24  * Copyright (c) 2012 by Delphix. All rights reserved.
25  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
26  */
27 
28 #ifndef _SYS_ZFS_CONTEXT_H
29 #define	_SYS_ZFS_CONTEXT_H
30 
31 #ifdef	__cplusplus
32 extern "C" {
33 #endif
34 
35 #define	_SYS_MUTEX_H
36 #define	_SYS_RWLOCK_H
37 #define	_SYS_CONDVAR_H
38 #define	_SYS_SYSTM_H
39 #define	_SYS_T_LOCK_H
40 #define	_SYS_VNODE_H
41 #define	_SYS_VFS_H
42 #define	_SYS_SUNDDI_H
43 #define	_SYS_CALLB_H
44 
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <stddef.h>
48 #include <stdarg.h>
49 #include <fcntl.h>
50 #include <unistd.h>
51 #include <errno.h>
52 #include <string.h>
53 #include <strings.h>
54 #include <synch.h>
55 #include <thread.h>
56 #include <assert.h>
57 #include <alloca.h>
58 #include <umem.h>
59 #include <limits.h>
60 #include <atomic.h>
61 #include <dirent.h>
62 #include <time.h>
63 #include <procfs.h>
64 #include <libsysevent.h>
65 #include <sys/note.h>
66 #include <sys/types.h>
67 #include <sys/cred.h>
68 #include <sys/sysmacros.h>
69 #include <sys/bitmap.h>
70 #include <sys/resource.h>
71 #include <sys/byteorder.h>
72 #include <sys/list.h>
73 #include <sys/uio.h>
74 #include <sys/zfs_debug.h>
75 #include <sys/sdt.h>
76 #include <sys/kstat.h>
77 #include <sys/u8_textprep.h>
78 #include <sys/sysevent/eventdefs.h>
79 #include <sys/sysevent/dev.h>
80 #include <sys/sunddi.h>
81 #include <sys/debug.h>
82 
83 /*
84  * Debugging
85  */
86 
87 /*
88  * Note that we are not using the debugging levels.
89  */
90 
91 #define	CE_CONT		0	/* continuation		*/
92 #define	CE_NOTE		1	/* notice		*/
93 #define	CE_WARN		2	/* warning		*/
94 #define	CE_PANIC	3	/* panic		*/
95 #define	CE_IGNORE	4	/* print nothing	*/
96 
97 /*
98  * ZFS debugging
99  */
100 
101 #ifdef ZFS_DEBUG
102 extern void dprintf_setup(int *argc, char **argv);
103 #endif /* ZFS_DEBUG */
104 
105 extern void cmn_err(int, const char *, ...);
106 extern void vcmn_err(int, const char *, __va_list);
107 extern void panic(const char *, ...);
108 extern void vpanic(const char *, __va_list);
109 
110 #define	fm_panic	panic
111 
112 extern int aok;
113 
114 /*
115  * DTrace SDT probes have different signatures in userland than they do in
116  * kernel.  If they're being used in kernel code, re-define them out of
117  * existence for their counterparts in libzpool.
118  */
119 
120 #ifdef DTRACE_PROBE
121 #undef	DTRACE_PROBE
122 #define	DTRACE_PROBE(a)	((void)0)
123 #endif	/* DTRACE_PROBE */
124 
125 #ifdef DTRACE_PROBE1
126 #undef	DTRACE_PROBE1
127 #define	DTRACE_PROBE1(a, b, c)	((void)0)
128 #endif	/* DTRACE_PROBE1 */
129 
130 #ifdef DTRACE_PROBE2
131 #undef	DTRACE_PROBE2
132 #define	DTRACE_PROBE2(a, b, c, d, e)	((void)0)
133 #endif	/* DTRACE_PROBE2 */
134 
135 #ifdef DTRACE_PROBE3
136 #undef	DTRACE_PROBE3
137 #define	DTRACE_PROBE3(a, b, c, d, e, f, g)	((void)0)
138 #endif	/* DTRACE_PROBE3 */
139 
140 #ifdef DTRACE_PROBE4
141 #undef	DTRACE_PROBE4
142 #define	DTRACE_PROBE4(a, b, c, d, e, f, g, h, i)	((void)0)
143 #endif	/* DTRACE_PROBE4 */
144 
145 /*
146  * Threads
147  */
148 #define	curthread	((void *)(uintptr_t)thr_self())
149 
150 typedef struct kthread kthread_t;
151 
152 #define	thread_create(stk, stksize, func, arg, len, pp, state, pri)	\
153 	zk_thread_create(func, arg)
154 #define	thread_exit() thr_exit(NULL)
155 #define	thread_join(t)	panic("libzpool cannot join threads")
156 
157 #define	newproc(f, a, cid, pri, ctp, pid)	(ENOSYS)
158 
159 /* in libzpool, p0 exists only to have its address taken */
160 struct proc {
161 	uintptr_t	this_is_never_used_dont_dereference_it;
162 };
163 
164 extern struct proc p0;
165 #define	curproc		(&p0)
166 
167 #define	PS_NONE		-1
168 
169 extern kthread_t *zk_thread_create(void (*func)(), void *arg);
170 
171 #define	issig(why)	(FALSE)
172 #define	ISSIG(thr, why)	(FALSE)
173 
174 /*
175  * Mutexes
176  */
177 typedef struct kmutex {
178 	void		*m_owner;
179 	boolean_t	initialized;
180 	mutex_t		m_lock;
181 } kmutex_t;
182 
183 #define	MUTEX_DEFAULT	USYNC_THREAD
184 #undef	MUTEX_HELD
185 #undef	MUTEX_NOT_HELD
186 #define	MUTEX_HELD(m) _mutex_held(&(m)->m_lock)
187 #define	MUTEX_NOT_HELD(m) (!MUTEX_HELD(m))
188 
189 /*
190  * Argh -- we have to get cheesy here because the kernel and userland
191  * have different signatures for the same routine.
192  */
193 extern int _mutex_init(mutex_t *mp, int type, void *arg);
194 extern int _mutex_destroy(mutex_t *mp);
195 
196 #define	mutex_init(mp, b, c, d)		zmutex_init((kmutex_t *)(mp))
197 #define	mutex_destroy(mp)		zmutex_destroy((kmutex_t *)(mp))
198 
199 extern void zmutex_init(kmutex_t *mp);
200 extern void zmutex_destroy(kmutex_t *mp);
201 extern void mutex_enter(kmutex_t *mp);
202 extern void mutex_exit(kmutex_t *mp);
203 extern int mutex_tryenter(kmutex_t *mp);
204 extern void *mutex_owner(kmutex_t *mp);
205 
206 /*
207  * RW locks
208  */
209 typedef struct krwlock {
210 	void		*rw_owner;
211 	boolean_t	initialized;
212 	rwlock_t	rw_lock;
213 } krwlock_t;
214 
215 typedef int krw_t;
216 
217 #define	RW_READER	0
218 #define	RW_WRITER	1
219 #define	RW_DEFAULT	USYNC_THREAD
220 
221 #undef RW_READ_HELD
222 #define	RW_READ_HELD(x)		_rw_read_held(&(x)->rw_lock)
223 
224 #undef RW_WRITE_HELD
225 #define	RW_WRITE_HELD(x)	_rw_write_held(&(x)->rw_lock)
226 
227 extern void rw_init(krwlock_t *rwlp, char *name, int type, void *arg);
228 extern void rw_destroy(krwlock_t *rwlp);
229 extern void rw_enter(krwlock_t *rwlp, krw_t rw);
230 extern int rw_tryenter(krwlock_t *rwlp, krw_t rw);
231 extern int rw_tryupgrade(krwlock_t *rwlp);
232 extern void rw_exit(krwlock_t *rwlp);
233 #define	rw_downgrade(rwlp) do { } while (0)
234 
235 extern uid_t crgetuid(cred_t *cr);
236 extern uid_t crgetruid(cred_t *cr);
237 extern gid_t crgetgid(cred_t *cr);
238 extern int crgetngroups(cred_t *cr);
239 extern gid_t *crgetgroups(cred_t *cr);
240 
241 /*
242  * Condition variables
243  */
244 typedef cond_t kcondvar_t;
245 
246 #define	CV_DEFAULT	USYNC_THREAD
247 
248 extern void cv_init(kcondvar_t *cv, char *name, int type, void *arg);
249 extern void cv_destroy(kcondvar_t *cv);
250 extern void cv_wait(kcondvar_t *cv, kmutex_t *mp);
251 extern clock_t cv_timedwait(kcondvar_t *cv, kmutex_t *mp, clock_t abstime);
252 extern void cv_signal(kcondvar_t *cv);
253 extern void cv_broadcast(kcondvar_t *cv);
254 
255 /*
256  * kstat creation, installation and deletion
257  */
258 extern kstat_t *kstat_create(char *, int,
259     char *, char *, uchar_t, ulong_t, uchar_t);
260 extern void kstat_install(kstat_t *);
261 extern void kstat_delete(kstat_t *);
262 
263 /*
264  * Kernel memory
265  */
266 #define	KM_SLEEP		UMEM_NOFAIL
267 #define	KM_PUSHPAGE		KM_SLEEP
268 #define	KM_NOSLEEP		UMEM_DEFAULT
269 #define	KMC_NODEBUG		UMC_NODEBUG
270 #define	KMC_NOTOUCH		0	/* not needed for userland caches */
271 #define	kmem_alloc(_s, _f)	umem_alloc(_s, _f)
272 #define	kmem_zalloc(_s, _f)	umem_zalloc(_s, _f)
273 #define	kmem_free(_b, _s)	umem_free(_b, _s)
274 #define	kmem_cache_create(_a, _b, _c, _d, _e, _f, _g, _h, _i) \
275 	umem_cache_create(_a, _b, _c, _d, _e, _f, _g, _h, _i)
276 #define	kmem_cache_destroy(_c)	umem_cache_destroy(_c)
277 #define	kmem_cache_alloc(_c, _f) umem_cache_alloc(_c, _f)
278 #define	kmem_cache_free(_c, _b)	umem_cache_free(_c, _b)
279 #define	kmem_debugging()	0
280 #define	kmem_cache_reap_now(_c)		/* nothing */
281 #define	kmem_cache_set_move(_c, _cb)	/* nothing */
282 #define	vmem_qcache_reap(_v)		/* nothing */
283 #define	POINTER_INVALIDATE(_pp)		/* nothing */
284 #define	POINTER_IS_VALID(_p)	0
285 
286 extern vmem_t *zio_arena;
287 
288 typedef umem_cache_t kmem_cache_t;
289 
290 typedef enum kmem_cbrc {
291 	KMEM_CBRC_YES,
292 	KMEM_CBRC_NO,
293 	KMEM_CBRC_LATER,
294 	KMEM_CBRC_DONT_NEED,
295 	KMEM_CBRC_DONT_KNOW
296 } kmem_cbrc_t;
297 
298 /*
299  * Task queues
300  */
301 typedef struct taskq taskq_t;
302 typedef uintptr_t taskqid_t;
303 typedef void (task_func_t)(void *);
304 
305 typedef struct taskq_ent {
306 	struct taskq_ent	*tqent_next;
307 	struct taskq_ent	*tqent_prev;
308 	task_func_t		*tqent_func;
309 	void			*tqent_arg;
310 	uintptr_t		tqent_flags;
311 } taskq_ent_t;
312 
313 #define	TQENT_FLAG_PREALLOC	0x1	/* taskq_dispatch_ent used */
314 
315 #define	TASKQ_PREPOPULATE	0x0001
316 #define	TASKQ_CPR_SAFE		0x0002	/* Use CPR safe protocol */
317 #define	TASKQ_DYNAMIC		0x0004	/* Use dynamic thread scheduling */
318 #define	TASKQ_THREADS_CPU_PCT	0x0008	/* Scale # threads by # cpus */
319 #define	TASKQ_DC_BATCH		0x0010	/* Mark threads as batch */
320 
321 #define	TQ_SLEEP	KM_SLEEP	/* Can block for memory */
322 #define	TQ_NOSLEEP	KM_NOSLEEP	/* cannot block for memory; may fail */
323 #define	TQ_NOQUEUE	0x02		/* Do not enqueue if can't dispatch */
324 #define	TQ_FRONT	0x08		/* Queue in front */
325 
326 
327 extern taskq_t *system_taskq;
328 
329 extern taskq_t	*taskq_create(const char *, int, pri_t, int, int, uint_t);
330 #define	taskq_create_proc(a, b, c, d, e, p, f) \
331 	    (taskq_create(a, b, c, d, e, f))
332 #define	taskq_create_sysdc(a, b, d, e, p, dc, f) \
333 	    (taskq_create(a, b, maxclsyspri, d, e, f))
334 extern taskqid_t taskq_dispatch(taskq_t *, task_func_t, void *, uint_t);
335 extern void	taskq_dispatch_ent(taskq_t *, task_func_t, void *, uint_t,
336     taskq_ent_t *);
337 extern void	taskq_destroy(taskq_t *);
338 extern void	taskq_wait(taskq_t *);
339 extern int	taskq_member(taskq_t *, void *);
340 extern void	system_taskq_init(void);
341 extern void	system_taskq_fini(void);
342 
343 #define	XVA_MAPSIZE	3
344 #define	XVA_MAGIC	0x78766174
345 
346 /*
347  * vnodes
348  */
349 typedef struct vnode {
350 	uint64_t	v_size;
351 	int		v_fd;
352 	char		*v_path;
353 } vnode_t;
354 
355 #define	AV_SCANSTAMP_SZ	32		/* length of anti-virus scanstamp */
356 
357 typedef struct xoptattr {
358 	timestruc_t	xoa_createtime;	/* Create time of file */
359 	uint8_t		xoa_archive;
360 	uint8_t		xoa_system;
361 	uint8_t		xoa_readonly;
362 	uint8_t		xoa_hidden;
363 	uint8_t		xoa_nounlink;
364 	uint8_t		xoa_immutable;
365 	uint8_t		xoa_appendonly;
366 	uint8_t		xoa_nodump;
367 	uint8_t		xoa_settable;
368 	uint8_t		xoa_opaque;
369 	uint8_t		xoa_av_quarantined;
370 	uint8_t		xoa_av_modified;
371 	uint8_t		xoa_av_scanstamp[AV_SCANSTAMP_SZ];
372 	uint8_t		xoa_reparse;
373 	uint8_t		xoa_offline;
374 	uint8_t		xoa_sparse;
375 } xoptattr_t;
376 
377 typedef struct vattr {
378 	uint_t		va_mask;	/* bit-mask of attributes */
379 	u_offset_t	va_size;	/* file size in bytes */
380 } vattr_t;
381 
382 
383 typedef struct xvattr {
384 	vattr_t		xva_vattr;	/* Embedded vattr structure */
385 	uint32_t	xva_magic;	/* Magic Number */
386 	uint32_t	xva_mapsize;	/* Size of attr bitmap (32-bit words) */
387 	uint32_t	*xva_rtnattrmapp;	/* Ptr to xva_rtnattrmap[] */
388 	uint32_t	xva_reqattrmap[XVA_MAPSIZE];	/* Requested attrs */
389 	uint32_t	xva_rtnattrmap[XVA_MAPSIZE];	/* Returned attrs */
390 	xoptattr_t	xva_xoptattrs;	/* Optional attributes */
391 } xvattr_t;
392 
393 typedef struct vsecattr {
394 	uint_t		vsa_mask;	/* See below */
395 	int		vsa_aclcnt;	/* ACL entry count */
396 	void		*vsa_aclentp;	/* pointer to ACL entries */
397 	int		vsa_dfaclcnt;	/* default ACL entry count */
398 	void		*vsa_dfaclentp;	/* pointer to default ACL entries */
399 	size_t		vsa_aclentsz;	/* ACE size in bytes of vsa_aclentp */
400 } vsecattr_t;
401 
402 #define	AT_TYPE		0x00001
403 #define	AT_MODE		0x00002
404 #define	AT_UID		0x00004
405 #define	AT_GID		0x00008
406 #define	AT_FSID		0x00010
407 #define	AT_NODEID	0x00020
408 #define	AT_NLINK	0x00040
409 #define	AT_SIZE		0x00080
410 #define	AT_ATIME	0x00100
411 #define	AT_MTIME	0x00200
412 #define	AT_CTIME	0x00400
413 #define	AT_RDEV		0x00800
414 #define	AT_BLKSIZE	0x01000
415 #define	AT_NBLOCKS	0x02000
416 #define	AT_SEQ		0x08000
417 #define	AT_XVATTR	0x10000
418 
419 #define	CRCREAT		0
420 
421 extern int fop_getattr(vnode_t *vp, vattr_t *vap);
422 
423 #define	VOP_CLOSE(vp, f, c, o, cr, ct)	0
424 #define	VOP_PUTPAGE(vp, of, sz, fl, cr, ct)	0
425 #define	VOP_GETATTR(vp, vap, fl, cr, ct)  fop_getattr((vp), (vap));
426 
427 #define	VOP_FSYNC(vp, f, cr, ct)	fsync((vp)->v_fd)
428 
429 #define	VN_RELE(vp)	vn_close(vp)
430 
431 extern int vn_open(char *path, int x1, int oflags, int mode, vnode_t **vpp,
432     int x2, int x3);
433 extern int vn_openat(char *path, int x1, int oflags, int mode, vnode_t **vpp,
434     int x2, int x3, vnode_t *vp, int fd);
435 extern int vn_rdwr(int uio, vnode_t *vp, void *addr, ssize_t len,
436     offset_t offset, int x1, int x2, rlim64_t x3, void *x4, ssize_t *residp);
437 extern void vn_close(vnode_t *vp);
438 
439 #define	vn_remove(path, x1, x2)		remove(path)
440 #define	vn_rename(from, to, seg)	rename((from), (to))
441 #define	vn_is_readonly(vp)		B_FALSE
442 
443 extern vnode_t *rootdir;
444 
445 #include <sys/file.h>		/* for FREAD, FWRITE, etc */
446 
447 /*
448  * Random stuff
449  */
450 #define	ddi_get_lbolt()		(gethrtime() >> 23)
451 #define	ddi_get_lbolt64()	(gethrtime() >> 23)
452 #define	hz	119	/* frequency when using gethrtime() >> 23 for lbolt */
453 
454 extern void delay(clock_t ticks);
455 
456 #define	SEC_TO_TICK(sec)	((sec) * hz)
457 #define	NSEC_TO_TICK(usec)	((usec) / (NANOSEC / hz))
458 
459 #define	gethrestime_sec() time(NULL)
460 #define	gethrestime(t) \
461 	do {\
462 		(t)->tv_sec = gethrestime_sec();\
463 		(t)->tv_nsec = 0;\
464 	} while (0);
465 
466 #define	max_ncpus	64
467 
468 #define	minclsyspri	60
469 #define	maxclsyspri	99
470 
471 #define	CPU_SEQID	(thr_self() & (max_ncpus - 1))
472 
473 #define	kcred		NULL
474 #define	CRED()		NULL
475 
476 #define	ptob(x)		((x) * PAGESIZE)
477 
478 extern uint64_t physmem;
479 
480 extern int highbit(ulong_t i);
481 extern int random_get_bytes(uint8_t *ptr, size_t len);
482 extern int random_get_pseudo_bytes(uint8_t *ptr, size_t len);
483 
484 extern void kernel_init(int);
485 extern void kernel_fini(void);
486 
487 struct spa;
488 extern void nicenum(uint64_t num, char *buf);
489 extern void show_pool_stats(struct spa *);
490 
491 typedef struct callb_cpr {
492 	kmutex_t	*cc_lockp;
493 } callb_cpr_t;
494 
495 #define	CALLB_CPR_INIT(cp, lockp, func, name)	{		\
496 	(cp)->cc_lockp = lockp;					\
497 }
498 
499 #define	CALLB_CPR_SAFE_BEGIN(cp) {				\
500 	ASSERT(MUTEX_HELD((cp)->cc_lockp));			\
501 }
502 
503 #define	CALLB_CPR_SAFE_END(cp, lockp) {				\
504 	ASSERT(MUTEX_HELD((cp)->cc_lockp));			\
505 }
506 
507 #define	CALLB_CPR_EXIT(cp) {					\
508 	ASSERT(MUTEX_HELD((cp)->cc_lockp));			\
509 	mutex_exit((cp)->cc_lockp);				\
510 }
511 
512 #define	zone_dataset_visible(x, y)	(1)
513 #define	INGLOBALZONE(z)			(1)
514 
515 extern char *kmem_asprintf(const char *fmt, ...);
516 #define	strfree(str) kmem_free((str), strlen(str)+1)
517 
518 /*
519  * Hostname information
520  */
521 extern char hw_serial[];	/* for userland-emulated hostid access */
522 extern int ddi_strtoul(const char *str, char **nptr, int base,
523     unsigned long *result);
524 
525 extern int ddi_strtoull(const char *str, char **nptr, int base,
526     u_longlong_t *result);
527 
528 /* ZFS Boot Related stuff. */
529 
530 struct _buf {
531 	intptr_t	_fd;
532 };
533 
534 struct bootstat {
535 	uint64_t st_size;
536 };
537 
538 typedef struct ace_object {
539 	uid_t		a_who;
540 	uint32_t	a_access_mask;
541 	uint16_t	a_flags;
542 	uint16_t	a_type;
543 	uint8_t		a_obj_type[16];
544 	uint8_t		a_inherit_obj_type[16];
545 } ace_object_t;
546 
547 
548 #define	ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE	0x05
549 #define	ACE_ACCESS_DENIED_OBJECT_ACE_TYPE	0x06
550 #define	ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE	0x07
551 #define	ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE	0x08
552 
553 extern struct _buf *kobj_open_file(char *name);
554 extern int kobj_read_file(struct _buf *file, char *buf, unsigned size,
555     unsigned off);
556 extern void kobj_close_file(struct _buf *file);
557 extern int kobj_get_filesize(struct _buf *file, uint64_t *size);
558 extern int zfs_secpolicy_snapshot_perms(const char *name, cred_t *cr);
559 extern int zfs_secpolicy_rename_perms(const char *from, const char *to,
560     cred_t *cr);
561 extern int zfs_secpolicy_destroy_perms(const char *name, cred_t *cr);
562 extern zoneid_t getzoneid(void);
563 
564 /* SID stuff */
565 typedef struct ksiddomain {
566 	uint_t	kd_ref;
567 	uint_t	kd_len;
568 	char	*kd_name;
569 } ksiddomain_t;
570 
571 ksiddomain_t *ksid_lookupdomain(const char *);
572 void ksiddomain_rele(ksiddomain_t *);
573 
574 #define	DDI_SLEEP	KM_SLEEP
575 #define	ddi_log_sysevent(_a, _b, _c, _d, _e, _f, _g) \
576 	sysevent_post_event(_c, _d, _b, "libzpool", _e, _f)
577 
578 /*
579  * Cyclic information
580  */
581 extern kmutex_t cpu_lock;
582 
583 typedef uintptr_t cyclic_id_t;
584 typedef uint16_t cyc_level_t;
585 typedef void (*cyc_func_t)(void *);
586 
587 #define	CY_LOW_LEVEL	0
588 #define	CY_INFINITY	INT64_MAX
589 #define	CYCLIC_NONE	((cyclic_id_t)0)
590 
591 typedef struct cyc_time {
592 	hrtime_t cyt_when;
593 	hrtime_t cyt_interval;
594 } cyc_time_t;
595 
596 typedef struct cyc_handler {
597 	cyc_func_t cyh_func;
598 	void *cyh_arg;
599 	cyc_level_t cyh_level;
600 } cyc_handler_t;
601 
602 extern cyclic_id_t cyclic_add(cyc_handler_t *, cyc_time_t *);
603 extern void cyclic_remove(cyclic_id_t);
604 extern int cyclic_reprogram(cyclic_id_t, hrtime_t);
605 
606 /*
607  * Buf structure
608  */
609 #define	B_BUSY		0x0001
610 #define	B_DONE		0x0002
611 #define	B_ERROR		0x0004
612 #define	B_READ		0x0040	/* read when I/O occurs */
613 #define	B_WRITE		0x0100	/* non-read pseudo-flag */
614 
615 typedef struct buf {
616 	int	b_flags;
617 	size_t b_bcount;
618 	union {
619 		caddr_t b_addr;
620 	} b_un;
621 
622 	lldaddr_t	_b_blkno;
623 #define	b_lblkno	_b_blkno._f
624 	size_t	b_resid;
625 	size_t	b_bufsize;
626 	int	(*b_iodone)(struct buf *);
627 	int	b_error;
628 	void	*b_private;
629 } buf_t;
630 
631 extern void bioinit(buf_t *);
632 extern void biodone(buf_t *);
633 extern void bioerror(buf_t *, int);
634 extern int geterror(buf_t *);
635 
636 #ifdef	__cplusplus
637 }
638 #endif
639 
640 #endif	/* _SYS_ZFS_CONTEXT_H */
641