1 /**
2 * collectd - src/lvm.c
3 * Copyright (C) 2013 Chad Malfait
4 * Copyright (C) 2014 Carnegie Mellon University
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; only version 2 of the License is applicable.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors:
20 * Chad Malfait <malfaitc at yahoo.com>
21 * Benjamin Gilbert <bgilbert at backtick.net>
22 **/
24 #include <lvm2app.h>
26 #include "collectd.h"
28 #include "common.h"
29 #include "plugin.h"
31 #define NO_VALUE UINT64_MAX
32 #define PERCENT_SCALE_FACTOR 1e-8
34 static uint64_t get_lv_property_int(lv_t lv, char const *property)
35 {
36 lvm_property_value_t v;
38 v = lvm_lv_get_property(lv, property);
39 if (!v.is_valid || !v.is_integer)
40 return NO_VALUE;
41 /* May be NO_VALUE if @property does not apply to this LV */
42 return v.value.integer;
43 }
45 static char const *get_lv_property_string(lv_t lv, char const *property)
46 {
47 lvm_property_value_t v;
49 v = lvm_lv_get_property(lv, property);
50 if (!v.is_valid || !v.is_string)
51 return NULL;
52 return v.value.string;
53 }
55 static void lvm_submit (char const *plugin_instance, char const *type_instance,
56 uint64_t ivalue)
57 {
58 value_list_t vl = VALUE_LIST_INIT;
60 vl.values = &(value_t) { .gauge = (gauge_t) ivalue };
61 vl.values_len = 1;
63 sstrncpy(vl.plugin, "lvm", sizeof (vl.plugin));
64 sstrncpy(vl.plugin_instance, plugin_instance, sizeof (vl.plugin_instance));
65 sstrncpy(vl.type, "df_complex", sizeof (vl.type));
66 sstrncpy(vl.type_instance, type_instance, sizeof (vl.type_instance));
68 plugin_dispatch_values (&vl);
69 }
71 static void report_lv_utilization(lv_t lv, char const *vg_name,
72 char const *lv_name, uint64_t lv_size,
73 char const *used_percent_property)
74 {
75 uint64_t used_percent_unscaled;
76 uint64_t used_bytes;
77 char plugin_instance[DATA_MAX_NAME_LEN];
79 used_percent_unscaled = get_lv_property_int(lv, used_percent_property);
80 if (used_percent_unscaled == NO_VALUE)
81 return;
82 used_bytes = lv_size * (used_percent_unscaled * PERCENT_SCALE_FACTOR);
84 ssnprintf(plugin_instance, sizeof(plugin_instance), "%s-%s",
85 vg_name, lv_name);
86 lvm_submit(plugin_instance, "used", used_bytes);
87 lvm_submit(plugin_instance, "free", lv_size - used_bytes);
88 }
90 static void report_thin_pool_utilization(lv_t lv, char const *vg_name,
91 uint64_t lv_size)
92 {
93 char const *data_lv;
94 char const *metadata_lv;
95 uint64_t metadata_size;
97 data_lv = get_lv_property_string(lv, "data_lv");
98 metadata_lv = get_lv_property_string(lv, "metadata_lv");
99 metadata_size = get_lv_property_int(lv, "lv_metadata_size");
100 if (data_lv == NULL || metadata_lv == NULL || metadata_size == NO_VALUE)
101 return;
103 report_lv_utilization(lv, vg_name, data_lv, lv_size, "data_percent");
104 report_lv_utilization(lv, vg_name, metadata_lv, metadata_size,
105 "metadata_percent");
106 }
108 static void vg_read(vg_t vg, char const *vg_name)
109 {
110 struct dm_list *lvs;
111 struct lvm_lv_list *lvl;
112 char const *name;
113 char const *attrs;
114 uint64_t size;
116 lvm_submit (vg_name, "free", lvm_vg_get_free_size(vg));
118 lvs = lvm_vg_list_lvs(vg);
119 if (!lvs) {
120 /* no VGs are defined, which is not an error per se */
121 return;
122 }
124 dm_list_iterate_items(lvl, lvs) {
125 name = lvm_lv_get_name(lvl->lv);
126 attrs = get_lv_property_string(lvl->lv, "lv_attr");
127 size = lvm_lv_get_size(lvl->lv);
128 if (name == NULL || attrs == NULL || size == NO_VALUE)
129 continue;
131 /* Condition on volume type. We want the reported sizes in the
132 volume group to sum to the size of the volume group, so we ignore
133 virtual volumes. */
134 switch (attrs[0]) {
135 case 's':
136 case 'S':
137 /* Snapshot. Also report used/free space. */
138 report_lv_utilization(lvl->lv, vg_name, name, size,
139 "data_percent");
140 break;
141 case 't':
142 /* Thin pool virtual volume. We report the underlying data
143 and metadata volumes, not this one. Report used/free
144 space, then ignore. */
145 report_thin_pool_utilization(lvl->lv, vg_name, size);
146 continue;
147 case 'v':
148 /* Virtual volume. Ignore. */
149 continue;
150 case 'V':
151 /* Thin volume or thin snapshot. Ignore. */
152 continue;
153 }
154 lvm_submit(vg_name, name, size);
155 }
156 }
158 static int lvm_read(void)
159 {
160 lvm_t lvm;
161 struct dm_list *vg_names;
162 struct lvm_str_list *name_list;
164 lvm = lvm_init(NULL);
165 if (!lvm) {
166 ERROR("lvm plugin: lvm_init failed.");
167 return (-1);
168 }
170 vg_names = lvm_list_vg_names(lvm);
171 if (!vg_names) {
172 ERROR("lvm plugin lvm_list_vg_name failed %s", lvm_errmsg(lvm));
173 lvm_quit(lvm);
174 return (-1);
175 }
177 dm_list_iterate_items(name_list, vg_names) {
178 vg_t vg;
180 vg = lvm_vg_open(lvm, name_list->str, "r", 0);
181 if (!vg) {
182 ERROR ("lvm plugin: lvm_vg_open (%s) failed: %s",
183 name_list->str, lvm_errmsg(lvm));
184 continue;
185 }
187 vg_read(vg, name_list->str);
188 lvm_vg_close(vg);
189 }
191 lvm_quit(lvm);
192 return (0);
193 } /*lvm_read */
195 void module_register(void)
196 {
197 plugin_register_read("lvm", lvm_read);
198 } /* void module_register */