xref: /freebsd/cddl/usr.sbin/zfsd/vdev_iterator.h (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * Copyright (c) 2011, 2012, 2013 Spectra Logic Corporation
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions, and the following disclaimer,
10  *    without modification.
11  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12  *    substantially similar to the "NO WARRANTY" disclaimer below
13  *    ("Disclaimer") and any redistribution must be conditioned upon
14  *    including a substantially similar Disclaimer requirement for further
15  *    binary redistribution.
16  *
17  * NO WARRANTY
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGES.
29  *
30  * Authors: Justin T. Gibbs     (Spectra Logic Corporation)
31  */
32 
33 /**
34  * \file vdev_iterator.h
35  *
36  * VdevIterator class definition.
37  *
38  * Header requirements:
39  *
40  *    #include <list>
41  */
42 #ifndef	_VDEV_ITERATOR_H_
43 #define	_VDEV_ITERATOR_H_
44 
45 /*=========================== Forward Declarations ===========================*/
46 struct zpool_handle;
47 typedef struct zpool_handle zpool_handle_t;
48 
49 struct nvlist;
50 typedef struct nvlist nvlist_t;
51 
52 class Vdev;
53 
54 /*============================= Class Definitions ============================*/
55 /*------------------------------- VdevIterator -------------------------------*/
56 typedef bool VdevCallback_t(Vdev &vdev, void *cbArg);
57 
58 /**
59  * \brief VdevIterator provides mechanisms for traversing and searching
60  *        the leaf vdevs contained in a ZFS pool configuration.
61  */
62 class VdevIterator
63 {
64 public:
65 	/**
66 	 * \brief Instantiate a VdevIterator for the given ZFS pool.
67 	 *
68 	 * \param pool  The ZFS pool to traverse/search.
69 	 */
70 	VdevIterator(zpool_handle_t *pool);
71 
72 	/**
73 	 * \brief Instantiate a VdevIterator for the given ZFS pool.
74 	 *
75 	 * \param poolConfig  The configuration data for the ZFS pool
76 	 *                    to traverse/search.
77 	 */
78 	VdevIterator(nvlist_t *poolConfig);
79 
80 	/**
81 	 * \brief Reset this iterator's cursor so that Next() will
82 	 *        report the first member of the pool.
83 	 */
84 	void      Reset();
85 
86 	/**
87 	 * \brief Report the leaf vdev at this iterator's cursor and increment
88 	 *        the cursor to the next leaf pool member.
89 	 */
90 	nvlist_t *Next();
91 
92 	/**
93 	 * \brief Traverse the entire pool configuration starting its
94 	 *        first member, returning a vdev object with the given
95 	 *        vdev GUID if found.
96 	 *
97 	 * \param vdevGUID  The vdev GUID of the vdev object to find.
98 	 *
99 	 * \return  A Vdev object for the matching vdev if found.  Otherwise
100 	 *          NULL.
101 	 *
102 	 * Upon return, the VdevIterator's cursor points to the vdev just
103 	 * past the returned vdev or end() if no matching vdev is found.
104 	 */
105 	nvlist_t *Find(DevdCtl::Guid vdevGUID);
106 
107 	/**
108 	 * \brief Perform the specified operation on each leaf member of
109 	 *        a pool's vdev membership.
110 	 *
111 	 * \param cb     Callback function to execute for each member.
112 	 * \param cbArg  Argument to pass to cb.
113 	 */
114 	void	  Each(VdevCallback_t *cb, void *cbArg);
115 
116 private:
117 	nvlist_t                *m_poolConfig;
118 	std::list<nvlist_t *>	 m_vdevQueue;
119 };
120 
121 #endif	/* _VDEV_ITERATOR_H_ */
122