[mirror_zfs.git] / zfs / lib / libzcommon / include / sys / vdev_impl.h

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef _SYS_VDEV_IMPL_H
#define	_SYS_VDEV_IMPL_H

#pragma ident	"@(#)vdev_impl.h	1.19	07/11/27 SMI"

#include <sys/avl.h>
#include <sys/dmu.h>
#include <sys/metaslab.h>
#include <sys/nvpair.h>
#include <sys/space_map.h>
#include <sys/vdev.h>
#include <sys/dkio.h>
#include <sys/uberblock_impl.h>

#ifdef	__cplusplus
extern "C" {
#endif

/*
 * Virtual device descriptors.
 *
 * All storage pool operations go through the virtual device framework,
 * which provides data replication and I/O scheduling.
 */

/*
 * Forward declarations that lots of things need.
 */
typedef struct vdev_queue vdev_queue_t;
typedef struct vdev_cache vdev_cache_t;
typedef struct vdev_cache_entry vdev_cache_entry_t;

/*
 * Virtual device operations
 */
typedef int	vdev_open_func_t(vdev_t *vd, uint64_t *size, uint64_t *ashift);
typedef void	vdev_close_func_t(vdev_t *vd);
typedef int	vdev_probe_func_t(vdev_t *vd);
typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
typedef int	vdev_io_start_func_t(zio_t *zio);
typedef int	vdev_io_done_func_t(zio_t *zio);
typedef void	vdev_state_change_func_t(vdev_t *vd, int, int);

typedef struct vdev_ops {
	vdev_open_func_t		*vdev_op_open;
	vdev_close_func_t		*vdev_op_close;
	vdev_probe_func_t		*vdev_op_probe;
	vdev_asize_func_t		*vdev_op_asize;
	vdev_io_start_func_t		*vdev_op_io_start;
	vdev_io_done_func_t		*vdev_op_io_done;
	vdev_state_change_func_t	*vdev_op_state_change;
	char				vdev_op_type[16];
	boolean_t			vdev_op_leaf;
} vdev_ops_t;

/*
 * Virtual device properties
 */
struct vdev_cache_entry {
	char		*ve_data;
	uint64_t	ve_offset;
	uint64_t	ve_lastused;
	avl_node_t	ve_offset_node;
	avl_node_t	ve_lastused_node;
	uint32_t	ve_hits;
	uint16_t	ve_missed_update;
	zio_t		*ve_fill_io;
};

struct vdev_cache {
	avl_tree_t	vc_offset_tree;
	avl_tree_t	vc_lastused_tree;
	kmutex_t	vc_lock;
};

struct vdev_queue {
	avl_tree_t	vq_deadline_tree;
	avl_tree_t	vq_read_tree;
	avl_tree_t	vq_write_tree;
	avl_tree_t	vq_pending_tree;
	kmutex_t	vq_lock;
};

/*
 * Virtual device descriptor
 */
struct vdev {
	/*
	 * Common to all vdev types.
	 */
	uint64_t	vdev_id;	/* child number in vdev parent	*/
	uint64_t	vdev_guid;	/* unique ID for this vdev	*/
	uint64_t	vdev_guid_sum;	/* self guid + all child guids	*/
	uint64_t	vdev_asize;	/* allocatable device capacity	*/
	uint64_t	vdev_ashift;	/* block alignment shift	*/
	uint64_t	vdev_state;	/* see VDEV_STATE_* #defines	*/
	uint64_t	vdev_prevstate;	/* used when reopening a vdev	*/
	vdev_ops_t	*vdev_ops;	/* vdev operations		*/
	spa_t		*vdev_spa;	/* spa for this vdev		*/
	void		*vdev_tsd;	/* type-specific data		*/
	vdev_t		*vdev_top;	/* top-level vdev		*/
	vdev_t		*vdev_parent;	/* parent vdev			*/
	vdev_t		**vdev_child;	/* array of children		*/
	uint64_t	vdev_children;	/* number of children		*/
	space_map_t	vdev_dtl_map;	/* dirty time log in-core state	*/
	space_map_t	vdev_dtl_scrub;	/* DTL for scrub repair writes	*/
	vdev_stat_t	vdev_stat;	/* virtual device statistics	*/

	/*
	 * Top-level vdev state.
	 */
	uint64_t	vdev_ms_array;	/* metaslab array object	*/
	uint64_t	vdev_ms_shift;	/* metaslab size shift		*/
	uint64_t	vdev_ms_count;	/* number of metaslabs		*/
	metaslab_group_t *vdev_mg;	/* metaslab group		*/
	metaslab_t	**vdev_ms;	/* metaslab array		*/
	txg_list_t	vdev_ms_list;	/* per-txg dirty metaslab lists	*/
	txg_list_t	vdev_dtl_list;	/* per-txg dirty DTL lists	*/
	txg_node_t	vdev_txg_node;	/* per-txg dirty vdev linkage	*/
	boolean_t	vdev_remove_wanted; /* async remove wanted?	*/
	list_node_t	vdev_dirty_node; /* config dirty list		*/
	uint64_t	vdev_deflate_ratio; /* deflation ratio (x512)	*/
	uint64_t	vdev_islog;	/* is an intent log device	*/

	/*
	 * Leaf vdev state.
	 */
	uint64_t	vdev_psize;	/* physical device capacity	*/
	space_map_obj_t	vdev_dtl;	/* dirty time log on-disk state	*/
	txg_node_t	vdev_dtl_node;	/* per-txg dirty DTL linkage	*/
	uint64_t	vdev_wholedisk;	/* true if this is a whole disk */
	uint64_t	vdev_offline;	/* persistent offline state	*/
	uint64_t	vdev_faulted;	/* persistent faulted state	*/
	uint64_t	vdev_degraded;	/* persistent degraded state	*/
	uint64_t	vdev_removed;	/* persistent removed state	*/
	uint64_t	vdev_nparity;	/* number of parity devices for raidz */
	char		*vdev_path;	/* vdev path (if any)		*/
	char		*vdev_devid;	/* vdev devid (if any)		*/
	char		*vdev_physpath;	/* vdev device path (if any)	*/
	uint64_t	vdev_fault_arg; /* fault injection paramater	*/
	int		vdev_fault_mask; /* zio types to fault		*/
	uint8_t		vdev_fault_mode; /* fault injection mode	*/
	uint8_t		vdev_tmpoffline; /* device taken offline temporarily? */
	uint8_t		vdev_detached;	/* device detached?		*/
	uint64_t	vdev_isspare;	/* was a hot spare		*/
	uint64_t	vdev_isl2cache;	/* was a l2cache device		*/
	vdev_queue_t	vdev_queue;	/* I/O deadline schedule queue	*/
	vdev_cache_t	vdev_cache;	/* physical block cache		*/
	uint64_t	vdev_not_present; /* not present during import	*/
	hrtime_t	vdev_last_try;	/* last reopen time		*/
	boolean_t	vdev_nowritecache; /* true if flushwritecache failed */
	uint64_t	vdev_unspare;	/* unspare when resilvering done */
	boolean_t	vdev_checkremove; /* temporary online test	*/
	boolean_t	vdev_forcefault; /* force online fault		*/
	boolean_t	vdev_is_failing; /* device errors seen		*/

	/*
	 * For DTrace to work in userland (libzpool) context, these fields must
	 * remain at the end of the structure.  DTrace will use the kernel's
	 * CTF definition for 'struct vdev', and since the size of a kmutex_t is
	 * larger in userland, the offsets for the rest fields would be
	 * incorrect.
	 */
	kmutex_t	vdev_dtl_lock;	/* vdev_dtl_{map,resilver}	*/
	kmutex_t	vdev_stat_lock;	/* vdev_stat			*/
};

#define	VDEV_SKIP_SIZE		(8 << 10)
#define	VDEV_BOOT_HEADER_SIZE	(8 << 10)
#define	VDEV_PHYS_SIZE		(112 << 10)
#define	VDEV_UBERBLOCK_RING	(128 << 10)

#define	VDEV_UBERBLOCK_SHIFT(vd)	\
	MAX((vd)->vdev_top->vdev_ashift, UBERBLOCK_SHIFT)
#define	VDEV_UBERBLOCK_COUNT(vd)	\
	(VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
#define	VDEV_UBERBLOCK_OFFSET(vd, n)	\
	offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
#define	VDEV_UBERBLOCK_SIZE(vd)		(1ULL << VDEV_UBERBLOCK_SHIFT(vd))

/* ZFS boot block */
#define	VDEV_BOOT_MAGIC		0x2f5b007b10cULL
#define	VDEV_BOOT_VERSION	1		/* version number	*/

typedef struct vdev_boot_header {
	uint64_t	vb_magic;		/* VDEV_BOOT_MAGIC	*/
	uint64_t	vb_version;		/* VDEV_BOOT_VERSION	*/
	uint64_t	vb_offset;		/* start offset	(bytes) */
	uint64_t	vb_size;		/* size (bytes)		*/
	char		vb_pad[VDEV_BOOT_HEADER_SIZE - 4 * sizeof (uint64_t)];
} vdev_boot_header_t;

typedef struct vdev_phys {
	char		vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_block_tail_t)];
	zio_block_tail_t vp_zbt;
} vdev_phys_t;

typedef struct vdev_label {
	char		vl_pad[VDEV_SKIP_SIZE];			/*   8K	*/
	vdev_boot_header_t vl_boot_header;			/*   8K	*/
	vdev_phys_t	vl_vdev_phys;				/* 112K	*/
	char		vl_uberblock[VDEV_UBERBLOCK_RING];	/* 128K	*/
} vdev_label_t;							/* 256K total */

/*
 * vdev_dirty() flags
 */
#define	VDD_METASLAB	0x01
#define	VDD_DTL		0x02

/*
 * Size and offset of embedded boot loader region on each label.
 * The total size of the first two labels plus the boot area is 4MB.
 */
#define	VDEV_BOOT_OFFSET	(2 * sizeof (vdev_label_t))
#define	VDEV_BOOT_SIZE		(7ULL << 19)			/* 3.5M	*/

/*
 * Size of label regions at the start and end of each leaf device.
 */
#define	VDEV_LABEL_START_SIZE	(2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
#define	VDEV_LABEL_END_SIZE	(2 * sizeof (vdev_label_t))
#define	VDEV_LABELS		4

#define	VDEV_ALLOC_LOAD		0
#define	VDEV_ALLOC_ADD		1
#define	VDEV_ALLOC_SPARE	2
#define	VDEV_ALLOC_L2CACHE	3

/*
 * Allocate or free a vdev
 */
extern int vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *config,
    vdev_t *parent, uint_t id, int alloctype);
extern void vdev_free(vdev_t *vd);

/*
 * Add or remove children and parents
 */
extern void vdev_add_child(vdev_t *pvd, vdev_t *cvd);
extern void vdev_remove_child(vdev_t *pvd, vdev_t *cvd);
extern void vdev_compact_children(vdev_t *pvd);
extern vdev_t *vdev_add_parent(vdev_t *cvd, vdev_ops_t *ops);
extern void vdev_remove_parent(vdev_t *cvd);

/*
 * vdev sync load and sync
 */
extern void vdev_load(vdev_t *vd);
extern void vdev_sync(vdev_t *vd, uint64_t txg);
extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
extern void vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg);

/*
 * Available vdev types.
 */
extern vdev_ops_t vdev_root_ops;
extern vdev_ops_t vdev_mirror_ops;
extern vdev_ops_t vdev_replacing_ops;
extern vdev_ops_t vdev_raidz_ops;
extern vdev_ops_t vdev_disk_ops;
extern vdev_ops_t vdev_file_ops;
extern vdev_ops_t vdev_missing_ops;
extern vdev_ops_t vdev_spare_ops;

/*
 * Common size functions
 */
extern uint64_t vdev_default_asize(vdev_t *vd, uint64_t psize);
extern uint64_t vdev_get_rsize(vdev_t *vd);

/*
 * zdb uses this tunable, so it must be declared here to make lint happy.
 */
extern int zfs_vdev_cache_size;

#ifdef	__cplusplus
}
#endif

#endif	/* _SYS_VDEV_IMPL_H */
Commit	Line	Data
34dc7c2f BB	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 2007 Sun Microsystems, Inc. All rights reserved.
	23	* Use is subject to license terms.
	24	*/
	25
	26	#ifndef _SYS_VDEV_IMPL_H
	27	#define _SYS_VDEV_IMPL_H
	28
	29	#pragma ident "@(#)vdev_impl.h 1.19 07/11/27 SMI"
	30
	31	#include <sys/avl.h>
	32	#include <sys/dmu.h>
	33	#include <sys/metaslab.h>
	34	#include <sys/nvpair.h>
	35	#include <sys/space_map.h>
	36	#include <sys/vdev.h>
	37	#include <sys/dkio.h>
	38	#include <sys/uberblock_impl.h>
	39
	40	#ifdef __cplusplus
	41	extern "C" {
	42	#endif
	43
	44	/*
	45	* Virtual device descriptors.
	46	*
	47	* All storage pool operations go through the virtual device framework,
	48	* which provides data replication and I/O scheduling.
	49	*/
	50
	51	/*
	52	* Forward declarations that lots of things need.
	53	*/
	54	typedef struct vdev_queue vdev_queue_t;
	55	typedef struct vdev_cache vdev_cache_t;
	56	typedef struct vdev_cache_entry vdev_cache_entry_t;
	57
	58	/*
	59	* Virtual device operations
	60	*/
	61	typedef int vdev_open_func_t(vdev_t vd, uint64_t size, uint64_t *ashift);
	62	typedef void vdev_close_func_t(vdev_t *vd);
	63	typedef int vdev_probe_func_t(vdev_t *vd);
	64	typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
65	typedef int vdev_io_start_func_t(zio_t *zio);
66	typedef int vdev_io_done_func_t(zio_t *zio);
67	typedef void vdev_state_change_func_t(vdev_t *vd, int, int);
68
69	typedef struct vdev_ops {
70	vdev_open_func_t *vdev_op_open;
71	vdev_close_func_t *vdev_op_close;
72	vdev_probe_func_t *vdev_op_probe;
73	vdev_asize_func_t *vdev_op_asize;
74	vdev_io_start_func_t *vdev_op_io_start;
75	vdev_io_done_func_t *vdev_op_io_done;
76	vdev_state_change_func_t *vdev_op_state_change;
77	char vdev_op_type[16];
78	boolean_t vdev_op_leaf;
79	} vdev_ops_t;
80
81	/*
82	* Virtual device properties
83	*/
84	struct vdev_cache_entry {
85	char *ve_data;
86	uint64_t ve_offset;
87	uint64_t ve_lastused;
88	avl_node_t ve_offset_node;
89	avl_node_t ve_lastused_node;
90	uint32_t ve_hits;
91	uint16_t ve_missed_update;
92	zio_t *ve_fill_io;
93	};
94
95	struct vdev_cache {
96	avl_tree_t vc_offset_tree;
97	avl_tree_t vc_lastused_tree;
98	kmutex_t vc_lock;
99	};
100
101	struct vdev_queue {
102	avl_tree_t vq_deadline_tree;
103	avl_tree_t vq_read_tree;
104	avl_tree_t vq_write_tree;
105	avl_tree_t vq_pending_tree;
106	kmutex_t vq_lock;
107	};
108
109	/*
110	* Virtual device descriptor
111	*/
112	struct vdev {
113	/*
114	* Common to all vdev types.
115	*/
116	uint64_t vdev_id; /* child number in vdev parent */
117	uint64_t vdev_guid; /* unique ID for this vdev */
118	uint64_t vdev_guid_sum; /* self guid + all child guids */
119	uint64_t vdev_asize; /* allocatable device capacity */
120	uint64_t vdev_ashift; /* block alignment shift */
121	uint64_t vdev_state; /* see VDEV_STATE_* #defines */
122	uint64_t vdev_prevstate; /* used when reopening a vdev */
123	vdev_ops_t vdev_ops; / vdev operations */
124	spa_t vdev_spa; / spa for this vdev */
125	void vdev_tsd; / type-specific data */
126	vdev_t vdev_top; / top-level vdev */
127	vdev_t vdev_parent; / parent vdev */
128	vdev_t *vdev_child; / array of children */
129	uint64_t vdev_children; /* number of children */
130	space_map_t vdev_dtl_map; /* dirty time log in-core state */
131	space_map_t vdev_dtl_scrub; /* DTL for scrub repair writes */
132	vdev_stat_t vdev_stat; /* virtual device statistics */
133
134	/*
135	* Top-level vdev state.
136	*/
137	uint64_t vdev_ms_array; /* metaslab array object */
138	uint64_t vdev_ms_shift; /* metaslab size shift */
139	uint64_t vdev_ms_count; /* number of metaslabs */
140	metaslab_group_t vdev_mg; / metaslab group */
141	metaslab_t *vdev_ms; / metaslab array */
142	txg_list_t vdev_ms_list; /* per-txg dirty metaslab lists */
143	txg_list_t vdev_dtl_list; /* per-txg dirty DTL lists */
144	txg_node_t vdev_txg_node; /* per-txg dirty vdev linkage */
145	boolean_t vdev_remove_wanted; /* async remove wanted? */
146	list_node_t vdev_dirty_node; /* config dirty list */
147	uint64_t vdev_deflate_ratio; /* deflation ratio (x512) */
148	uint64_t vdev_islog; /* is an intent log device */
149
150	/*
151	* Leaf vdev state.
152	*/
153	uint64_t vdev_psize; /* physical device capacity */
154	space_map_obj_t vdev_dtl; /* dirty time log on-disk state */
155	txg_node_t vdev_dtl_node; /* per-txg dirty DTL linkage */
156	uint64_t vdev_wholedisk; /* true if this is a whole disk */
157	uint64_t vdev_offline; /* persistent offline state */
158	uint64_t vdev_faulted; /* persistent faulted state */
159	uint64_t vdev_degraded; /* persistent degraded state */
160	uint64_t vdev_removed; /* persistent removed state */
161	uint64_t vdev_nparity; /* number of parity devices for raidz */
162	char vdev_path; / vdev path (if any) */
163	char vdev_devid; / vdev devid (if any) */
164	char vdev_physpath; / vdev device path (if any) */
165	uint64_t vdev_fault_arg; /* fault injection paramater */
166	int vdev_fault_mask; /* zio types to fault */
167	uint8_t vdev_fault_mode; /* fault injection mode */
168	uint8_t vdev_tmpoffline; /* device taken offline temporarily? */
169	uint8_t vdev_detached; /* device detached? */
170	uint64_t vdev_isspare; /* was a hot spare */
171	uint64_t vdev_isl2cache; /* was a l2cache device */
172	vdev_queue_t vdev_queue; /* I/O deadline schedule queue */
173	vdev_cache_t vdev_cache; /* physical block cache */
174	uint64_t vdev_not_present; /* not present during import */
175	hrtime_t vdev_last_try; /* last reopen time */
176	boolean_t vdev_nowritecache; /* true if flushwritecache failed */
177	uint64_t vdev_unspare; /* unspare when resilvering done */
178	boolean_t vdev_checkremove; /* temporary online test */
179	boolean_t vdev_forcefault; /* force online fault */
180	boolean_t vdev_is_failing; /* device errors seen */
181
182	/*
183	* For DTrace to work in userland (libzpool) context, these fields must
184	* remain at the end of the structure. DTrace will use the kernel's
185	* CTF definition for 'struct vdev', and since the size of a kmutex_t is
186	* larger in userland, the offsets for the rest fields would be
187	* incorrect.
188	*/
189	kmutex_t vdev_dtl_lock; /* vdev_dtl_{map,resilver} */
190	kmutex_t vdev_stat_lock; /* vdev_stat */
191	};
192
193	#define VDEV_SKIP_SIZE (8 << 10)
194	#define VDEV_BOOT_HEADER_SIZE (8 << 10)
195	#define VDEV_PHYS_SIZE (112 << 10)
196	#define VDEV_UBERBLOCK_RING (128 << 10)
197
198	#define VDEV_UBERBLOCK_SHIFT(vd) \
199	MAX((vd)->vdev_top->vdev_ashift, UBERBLOCK_SHIFT)
200	#define VDEV_UBERBLOCK_COUNT(vd) \
201	(VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
202	#define VDEV_UBERBLOCK_OFFSET(vd, n) \
203	offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
204	#define VDEV_UBERBLOCK_SIZE(vd) (1ULL << VDEV_UBERBLOCK_SHIFT(vd))
205
206	/* ZFS boot block */
207	#define VDEV_BOOT_MAGIC 0x2f5b007b10cULL
208	#define VDEV_BOOT_VERSION 1 /* version number */
209
210	typedef struct vdev_boot_header {
211	uint64_t vb_magic; /* VDEV_BOOT_MAGIC */
212	uint64_t vb_version; /* VDEV_BOOT_VERSION */
213	uint64_t vb_offset; /* start offset (bytes) */
214	uint64_t vb_size; /* size (bytes) */
215	char vb_pad[VDEV_BOOT_HEADER_SIZE - 4 * sizeof (uint64_t)];
216	} vdev_boot_header_t;
217
218	typedef struct vdev_phys {
219	char vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_block_tail_t)];
220	zio_block_tail_t vp_zbt;
221	} vdev_phys_t;
222
223	typedef struct vdev_label {
224	char vl_pad[VDEV_SKIP_SIZE]; /* 8K */
225	vdev_boot_header_t vl_boot_header; /* 8K */
226	vdev_phys_t vl_vdev_phys; /* 112K */
227	char vl_uberblock[VDEV_UBERBLOCK_RING]; /* 128K */
228	} vdev_label_t; /* 256K total */
229
230	/*
231	* vdev_dirty() flags
232	*/
233	#define VDD_METASLAB 0x01
234	#define VDD_DTL 0x02
235
236	/*
237	* Size and offset of embedded boot loader region on each label.
238	* The total size of the first two labels plus the boot area is 4MB.
239	*/
240	#define VDEV_BOOT_OFFSET (2 * sizeof (vdev_label_t))
241	#define VDEV_BOOT_SIZE (7ULL << 19) /* 3.5M */
242
243	/*
244	* Size of label regions at the start and end of each leaf device.
245	*/
246	#define VDEV_LABEL_START_SIZE (2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
247	#define VDEV_LABEL_END_SIZE (2 * sizeof (vdev_label_t))
248	#define VDEV_LABELS 4
249
250	#define VDEV_ALLOC_LOAD 0
251	#define VDEV_ALLOC_ADD 1
252	#define VDEV_ALLOC_SPARE 2
253	#define VDEV_ALLOC_L2CACHE 3
254
255	/*
256	* Allocate or free a vdev
257	*/
258	extern int vdev_alloc(spa_t spa, vdev_t vdp, nvlist_t config,
259	vdev_t *parent, uint_t id, int alloctype);
260	extern void vdev_free(vdev_t *vd);
261
262	/*
263	* Add or remove children and parents
264	*/
265	extern void vdev_add_child(vdev_t pvd, vdev_t cvd);
266	extern void vdev_remove_child(vdev_t pvd, vdev_t cvd);
267	extern void vdev_compact_children(vdev_t *pvd);
268	extern vdev_t vdev_add_parent(vdev_t cvd, vdev_ops_t *ops);
269	extern void vdev_remove_parent(vdev_t *cvd);
270
271	/*
272	* vdev sync load and sync
273	*/
274	extern void vdev_load(vdev_t *vd);
275	extern void vdev_sync(vdev_t *vd, uint64_t txg);
276	extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
277	extern void vdev_dirty(vdev_t vd, int flags, void arg, uint64_t txg);
278
279	/*
280	* Available vdev types.
281	*/
282	extern vdev_ops_t vdev_root_ops;
283	extern vdev_ops_t vdev_mirror_ops;
284	extern vdev_ops_t vdev_replacing_ops;
285	extern vdev_ops_t vdev_raidz_ops;
286	extern vdev_ops_t vdev_disk_ops;
287	extern vdev_ops_t vdev_file_ops;
288	extern vdev_ops_t vdev_missing_ops;
289	extern vdev_ops_t vdev_spare_ops;
290
291	/*
292	* Common size functions
293	*/
294	extern uint64_t vdev_default_asize(vdev_t *vd, uint64_t psize);
295	extern uint64_t vdev_get_rsize(vdev_t *vd);
296
297	/*
298	* zdb uses this tunable, so it must be declared here to make lint happy.
299	*/
300	extern int zfs_vdev_cache_size;
301
302	#ifdef __cplusplus
303	}
304	#endif
305
306	#endif /* _SYS_VDEV_IMPL_H */