1 /*      $NetBSD: filter_netbsd.c,v 1.4 2012/01/04 16:37:45 mhitch Exp $        */
2 
3 /*
4  * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
5  * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
6  * Copyright (C) 2008 Adam Hamsik. All rights reserved.
7  *
8  * This file is part of LVM2.
9  *
10  * This copyrighted material is made available to anyone wishing to use,
11  * modify, copy, or redistribute it subject to the terms and conditions
12  * of the GNU Lesser General Public License v.2.1.
13  *
14  * You should have received a copy of the GNU Lesser General Public License
15  * along with this program; if not, write to the Free Software Foundation,
16  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
17  */
18 
19 #include "lib.h"
20 #include "dev-cache.h"
21 #include "filter.h"
22 #include "lvm-string.h"
23 #include "config.h"
24 #include "metadata.h"
25 #include "activate.h"
26 
27 #include <sys/sysctl.h>
28 
29 #include <ctype.h>
30 #include <dirent.h>
31 #include <fcntl.h>
32 #include <limits.h>
33 #include <unistd.h>
34 
35 #define NUMBER_OF_MAJORS 4096
36 
37 #define LVM_SUCCESS 1
38 #define LVM_FAILURE 0
39 
40 /* -1 means LVM won't use this major number. */
41 static int _char_device_major[NUMBER_OF_MAJORS];
42 static int _block_device_major[NUMBER_OF_MAJORS];
43 
44 typedef struct {
45           const char *name;
46           const int max_partitions;
47 } device_info_t;
48 
49 static int _md_major = -1;
50 static int _device_mapper_major = -1;
51 
md_major(void)52 int md_major(void)
53 {
54           return _md_major;
55 }
56 
dev_subsystem_part_major(const struct device * dev)57 int dev_subsystem_part_major(const struct device *dev)
58 {
59           return 0;
60 }
61 
dev_subsystem_name(const struct device * dev)62 const char *dev_subsystem_name(const struct device *dev)
63 {
64           return "";
65 }
66 
67 /*
68  * Devices are only checked for partition tables if their minor number
69  * is a multiple of the number corresponding to their type below
70  * i.e. this gives the granularity of whole-device minor numbers.
71  * Use 1 if the device is not partitionable.
72  *
73  * The list can be supplemented with devices/types in the config file.
74  */
75 static const device_info_t device_info[] = {
76           {"wd", 64},
77           {"sd", 64},
78           {"dk", 1},
79           {"wd", 64},
80           {"vnd", 1},
81           {"raid", 64},
82           {"cgd", 1},
83           {"ccd", 1},
84           {"xbd", 64},
85           {"ld", 64},
86           {NULL, -1}
87 };
88 
89 /*
90  * Test if device passes filter tests and can be inserted in to cache.
91  */
_passes_lvm_type_device_filter(struct dev_filter * f __attribute ((unused)),struct device * dev)92 static int _passes_lvm_type_device_filter(struct dev_filter *f __attribute((unused)),
93                                                     struct device *dev)
94 {
95           const char *name = dev_name(dev);
96           int ret = 0;
97           uint64_t size;
98 
99           /* Is this a recognised device type? */
100           if (_char_device_major[MAJOR(dev->dev)] == -1 ){
101                     log_debug("%s: Skipping: Unrecognised LVM device type %"
102                                           PRIu64, name, (uint64_t) MAJOR(dev->dev));
103                     return LVM_FAILURE;
104           }
105 
106           /* Skip suspended devices */
107           if (MAJOR(dev->dev) == _device_mapper_major &&
108               ignore_suspended_devices() && !device_is_usable(dev->dev)) {
109                     log_debug("%s: Skipping: Suspended dm device", name);
110                     return LVM_FAILURE;
111           }
112 
113           /* Check it's accessible */
114           if (!dev_open_flags(dev, O_RDONLY, 0, 1)) {
115                     log_debug("%s: Skipping: open failed", name);
116                     return LVM_FAILURE;
117           }
118 
119           /* Check it's not too small */
120           if (!dev_get_size(dev, &size)) {
121                     log_debug("%s: Skipping: dev_get_size failed", name);
122                     goto out;
123           }
124 
125           if (size < PV_MIN_SIZE) {
126                     log_debug("%s: Skipping: Too small to hold a PV", name);
127                     goto out;
128           }
129 
130           if (is_partitioned_dev(dev)) {
131                     log_debug("%s: Skipping: Partition table signature found",
132                                 name);
133                     goto out;
134           }
135 
136           ret = LVM_SUCCESS;
137 
138       out:
139           dev_close(dev);
140 
141           return ret;
142 }
143 
_scan_dev(const struct config_node * cn)144 static int _scan_dev(const struct config_node *cn)
145 {
146           size_t val_len,i,j;
147           char *name;
148 
149           struct kinfo_drivers *kd;
150           struct config_value *cv;
151 
152           /* All types unrecognised initially */
153           memset(_char_device_major, -1, sizeof(int) * NUMBER_OF_MAJORS);
154           memset(_block_device_major, -1, sizeof(int) * NUMBER_OF_MAJORS);
155 
156           /* get size kernel drivers array from kernel*/
157           if (sysctlbyname("kern.drivers", NULL, &val_len, NULL, 0) < 0) {
158                     printf("sysctlbyname failed");
159                     return LVM_FAILURE;
160           }
161 
162           if ((kd = malloc(val_len)) == NULL){
163                     printf("malloc kd info error\n");
164                     return LVM_FAILURE;
165           }
166 
167           /* get array from kernel */
168           if (sysctlbyname("kern.drivers", kd, &val_len, NULL, 0) < 0) {
169                     printf("sysctlbyname failed kd");
170                     return LVM_FAILURE;
171           }
172 
173           for (i = 0, val_len /= sizeof(*kd); i < val_len; i++) {
174 
175                     if (!strncmp("device-mapper", kd[i].d_name, 13) ||
176                         !strncmp("dm", kd[i].d_name, 2))
177                               _device_mapper_major = kd[i].d_bmajor;
178 
179                     /* We select only devices with correct char/block major number. */
180                     if (kd[i].d_cmajor != -1 && kd[i].d_bmajor != -1) {
181                               /* Go through the valid device names and if there is a
182                                  match store max number of partitions */
183                               for (j = 0; device_info[j].name != NULL; j++){
184                                         if (!strcmp(device_info[j].name, kd[i].d_name)){
185                                                   _char_device_major[kd[i].d_cmajor] =
186                                                       device_info[j].max_partitions;
187                                                   _block_device_major[kd[i].d_bmajor] =
188                                                       device_info[j].max_partitions;
189                                                   break;
190                                         }
191                               }
192                     }
193 
194                     if (!cn)
195                               continue;
196 
197                     /* Check devices/types for local variations */
198                     for (cv = cn->v; cv; cv = cv->next) {
199                               if (cv->type != CFG_STRING) {
200                                         log_error("Expecting string in devices/types "
201                                                     "in config file");
202                                         free(kd);
203                                         return LVM_FAILURE;
204                               }
205 
206                               name = cv->v.str;
207                               cv = cv->next;
208                               if (!cv || cv->type != CFG_INT) {
209                                         log_error("Max partition count missing for %s "
210                                                     "in devices/types in config file",
211                                                     name);
212                                         free(kd);
213                                         return LVM_FAILURE;
214                               }
215                               if (!cv->v.i) {
216                                         log_error("Zero partition count invalid for "
217                                                     "%s in devices/types in config file",
218                                                     name);
219                                         free(kd);
220                                         return LVM_FAILURE;
221                               }
222 
223                               if (!strncmp(name, kd[i].d_name, strlen(name))){
224                                                   _char_device_major[kd[i].d_cmajor] =
225                                                       cv->v.i;
226                                                   _block_device_major[kd[i].d_bmajor] =
227                                                       cv->v.i;
228                                                   break;
229                               }
230                     }
231           }
232 
233           free(kd);
234 
235           return LVM_SUCCESS;
236 }
237 
max_partitions(int major)238 int max_partitions(int major)
239 {
240           return _char_device_major[major];
241 }
242 
lvm_type_filter_create(const char * proc,const struct config_node * cn)243 struct dev_filter *lvm_type_filter_create(const char *proc,
244                                                     const struct config_node *cn)
245 {
246           struct dev_filter *f;
247 
248           if (!(f = dm_malloc(sizeof(struct dev_filter)))) {
249                     log_error("LVM type filter allocation failed");
250                     return NULL;
251           }
252 
253           f->passes_filter = _passes_lvm_type_device_filter;
254           f->destroy = lvm_type_filter_destroy;
255           f->private = NULL;
256 
257           if (!_scan_dev(cn)) {
258                     dm_free(f);
259                     return_NULL;
260           }
261 
262           return f;
263 }
264 
lvm_type_filter_destroy(struct dev_filter * f)265 void lvm_type_filter_destroy(struct dev_filter *f)
266 {
267           dm_free(f);
268           return;
269 }
270