xref: /freebsd/cddl/usr.sbin/zfsd/vdev_iterator.cc (revision b9f654b163bce26de79705e77b872427c9f2afa1)
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  * $FreeBSD$
33  */
34 
35 /**
36  * \file vdev_iterator.cc
37  *
38  * Implementation of the VdevIterator class.
39  */
40 #include <sys/cdefs.h>
41 #include <sys/fs/zfs.h>
42 
43 #include <stdint.h>
44 #include <syslog.h>
45 
46 #include <libzfs.h>
47 
48 #include <list>
49 #include <string>
50 
51 #include <devdctl/exception.h>
52 #include <devdctl/guid.h>
53 
54 #include "vdev.h"
55 #include "vdev_iterator.h"
56 #include "zfsd_exception.h"
57 
58 /*============================ Namespace Control =============================*/
59 using DevdCtl::Guid;
60 
61 /*=========================== Class Implementations ==========================*/
62 /*------------------------------- VdevIterator -------------------------------*/
63 VdevIterator::VdevIterator(zpool_handle_t *pool)
64  : m_poolConfig(zpool_get_config(pool, NULL))
65 {
66 	Reset();
67 }
68 
69 VdevIterator::VdevIterator(nvlist_t *poolConfig)
70  : m_poolConfig(poolConfig)
71 {
72 	Reset();
73 }
74 
75 void
76 VdevIterator::Reset()
77 {
78 	nvlist_t  *rootVdev;
79 	nvlist	  **cache_child;
80 	int	   result;
81 	uint_t   cache_children;
82 
83 	result = nvlist_lookup_nvlist(m_poolConfig,
84 				      ZPOOL_CONFIG_VDEV_TREE,
85 				      &rootVdev);
86 	if (result != 0)
87 		throw ZfsdException(m_poolConfig, "Unable to extract "
88 				    "ZPOOL_CONFIG_VDEV_TREE from pool.");
89 	m_vdevQueue.assign(1, rootVdev);
90 	result = nvlist_lookup_nvlist_array(rootVdev,
91 				      	    ZPOOL_CONFIG_L2CACHE,
92 				      	    &cache_child,
93 					    &cache_children);
94 	if (result == 0)
95 		for (uint_t c = 0; c < cache_children; c++)
96 			m_vdevQueue.push_back(cache_child[c]);
97 }
98 
99 nvlist_t *
100 VdevIterator::Next()
101 {
102 	nvlist_t *vdevConfig;
103 
104 	if (m_vdevQueue.empty())
105 		return (NULL);
106 
107 	for (;;) {
108 		nvlist_t **vdevChildren;
109 		int        result;
110 		u_int      numChildren;
111 
112 		vdevConfig = m_vdevQueue.front();
113 		m_vdevQueue.pop_front();
114 
115 		/* Expand non-leaf vdevs. */
116 		result = nvlist_lookup_nvlist_array(vdevConfig,
117 						    ZPOOL_CONFIG_CHILDREN,
118 						   &vdevChildren, &numChildren);
119 		if (result != 0) {
120 			/* leaf vdev */
121 			break;
122 		}
123 
124 		/*
125 		 * Insert children at the head of the queue to effect a
126 		 * depth first traversal of the tree.
127 		 */
128 		m_vdevQueue.insert(m_vdevQueue.begin(), vdevChildren,
129 				   vdevChildren + numChildren);
130 	}
131 
132 	return (vdevConfig);
133 }
134 
135 void
136 VdevIterator::Each(VdevCallback_t *callBack, void *callBackArg)
137 {
138 	nvlist_t *vdevConfig;
139 
140 	Reset();
141 	while ((vdevConfig = Next()) != NULL) {
142 		Vdev vdev(m_poolConfig, vdevConfig);
143 
144 		if (callBack(vdev, callBackArg))
145 			break;
146 	}
147 }
148 
149 nvlist_t *
150 VdevIterator::Find(Guid vdevGUID)
151 {
152 	nvlist_t *vdevConfig;
153 
154 	Reset();
155 	while ((vdevConfig = Next()) != NULL) {
156 		Vdev vdev(m_poolConfig, vdevConfig);
157 
158 		if (vdev.GUID() == vdevGUID)
159 			return (vdevConfig);
160 	}
161 	return (NULL);
162 }
163