]> git.ipfire.org Git - thirdparty/mdadm.git/blame - sysfs.c
Support new offset layout for raid10
[thirdparty/mdadm.git] / sysfs.c
CommitLineData
e86c9dd6
NB
1/*
2 * sysfs - extract md related information from sysfs. Part of:
3 * mdadm - manage Linux "md" devices aka RAID arrays.
4 *
5 * Copyright (C) 2006 Neil Brown <neilb@suse.de>
6 *
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 * Author: Neil Brown
23 * Email: <neilb@suse.de>
24 */
25
26#include "mdadm.h"
27#include <dirent.h>
28
29int load_sys(char *path, char *buf)
30{
31 int fd = open(path, O_RDONLY);
32 int n;
33 if (fd < 0)
34 return -1;
35 n = read(fd, buf, 1024);
36 close(fd);
37 if (n <=0 || n >= 1024)
38 return -1;
39 buf[n] = 0;
40 if (buf[n-1] == '\n')
41 buf[n-1] = 0;
42 return 0;
43}
44
45struct sysarray *sysfs_read(int fd, int devnum, unsigned long options)
46{
47 /* Longest possible name in sysfs, mounted at /sys, is
48 * /sys/block/md_dXXX/md/dev-XXXXX/block/dev
49 * /sys/block/md_dXXX/md/metadata_version
50 * which is about 41 characters. 50 should do for now
51 */
52 char fname[50];
53 char buf[1024];
54 char *base;
55 char *dbase;
56 struct sysarray *sra;
57 struct sysdev *dev;
58 DIR *dir;
59 struct dirent *de;
60
61 sra = malloc(sizeof(*sra));
62 if (sra == NULL)
63 return sra;
64
65 if (fd >= 0) {
66 struct stat stb;
67 if (fstat(fd, &stb)) return NULL;
68 if (major(stb.st_rdev)==9)
69 sprintf(sra->name, "md%d", minor(stb.st_rdev));
70 else
71 sprintf(sra->name, "md_d%d",
7fa42a0b 72 minor(stb.st_rdev)>>MdpMinorShift);
e86c9dd6
NB
73 } else {
74 if (devnum >= 0)
75 sprintf(sra->name, "md%d", devnum);
76 else
77 sprintf(sra->name, "md_d%d",
78 -1-devnum);
79 }
80 sprintf(fname, "/sys/block/%s/md/", sra->name);
81 base = fname + strlen(fname);
82
83 sra->devs = NULL;
84 if (options & GET_LEVEL) {
85 strcpy(base, "level");
86 if (load_sys(fname, buf))
87 goto abort;
88 sra->level = map_name(pers, buf);
89 }
90 if (options & GET_LAYOUT) {
91 strcpy(base, "layout");
92 if (load_sys(fname, buf))
93 goto abort;
94 sra->layout = strtoul(buf, NULL, 0);
95 }
96 if (options & GET_COMPONENT) {
97 strcpy(base, "component_size");
98 if (load_sys(fname, buf))
99 goto abort;
100 sra->component_size = strtoull(buf, NULL, 0);
353632d9
NB
101 /* sysfs reports "K", but we want sectors */
102 sra->component_size *= 2;
e86c9dd6
NB
103 }
104 if (options & GET_CHUNK) {
105 strcpy(base, "chunk_size");
106 if (load_sys(fname, buf))
107 goto abort;
108 sra->chunk = strtoul(buf, NULL, 0);
109 }
110
111 if (! (options & GET_DEVS))
112 return sra;
113
114 /* Get all the devices as well */
115 *base = 0;
116 dir = opendir(fname);
117 if (!dir)
118 goto abort;
119 sra->spares = 0;
120
121 while ((de = readdir(dir)) != NULL) {
122 char *ep;
123 if (de->d_ino == 0 ||
124 strncmp(de->d_name, "dev-", 4) != 0)
125 continue;
126 strcpy(base, de->d_name);
127 dbase = base + strlen(base);
128 *dbase++ = '/';
129
130 dev = malloc(sizeof(*dev));
131 if (!dev)
132 goto abort;
133 dev->next = sra->devs;
134 sra->devs = dev;
135
136 /* Always get slot, major, minor */
137 strcpy(dbase, "slot");
138 if (load_sys(fname, buf))
139 goto abort;
140 dev->role = strtoul(buf, &ep, 10);
141 if (*ep) dev->role = -1;
142
143 strcpy(dbase, "block/dev");
144 if (load_sys(fname, buf))
145 goto abort;
146 sscanf(buf, "%d:%d", &dev->major, &dev->minor);
147
148 if (options & GET_OFFSET) {
149 strcpy(dbase, "offset");
150 if (load_sys(fname, buf))
151 goto abort;
152 dev->offset = strtoull(buf, NULL, 0);
153 }
154 if (options & GET_SIZE) {
155 strcpy(dbase, "size");
156 if (load_sys(fname, buf))
157 goto abort;
158 dev->size = strtoull(buf, NULL, 0);
159 }
160 if (options & GET_STATE) {
161 dev->state = 0;
162 strcpy(dbase, "state");
163 if (load_sys(fname, buf))
164 goto abort;
165 if (strstr(buf, "in_sync"))
166 dev->state |= (1<<MD_DISK_SYNC);
167 if (strstr(buf, "faulty"))
168 dev->state |= (1<<MD_DISK_FAULTY);
169 if (dev->state == 0)
170 sra->spares++;
171 }
172 if (options & GET_ERROR) {
173 strcpy(buf, "errors");
174 if (load_sys(fname, buf))
175 goto abort;
176 dev->errors = strtoul(buf, NULL, 0);
177 }
178 }
179 return sra;
180
181 abort:
182 while (sra && sra->devs) {
183 dev = sra->devs;
184 sra->devs = dev->next;
185 free(dev);
186 }
187 if(sra) free(sra);
188 return NULL;
189}
190
191unsigned long long get_component_size(int fd)
192{
193 /* Find out the component size of the array.
194 * We cannot trust GET_ARRAY_INFO ioctl as it's
195 * size field is only 32bits.
196 * So look in /sys/block/mdXXX/md/component_size
353632d9
NB
197 *
198 * WARNING: this returns in units of Kilobytes.
e86c9dd6
NB
199 */
200 struct stat stb;
201 char fname[50];
202 int n;
203 if (fstat(fd, &stb)) return 0;
204 if (major(stb.st_rdev) == 9)
205 sprintf(fname, "/sys/block/md%d/md/component_size",
206 minor(stb.st_rdev));
207 else
208 sprintf(fname, "/sys/block/md_d%d/md/component_size",
7fa42a0b 209 minor(stb.st_rdev)>>MdpMinorShift);
e86c9dd6
NB
210 fd = open(fname, O_RDONLY);
211 if (fd < 0)
212 return 0;
213 n = read(fd, fname, sizeof(fname));
214 close(fd);
215 if (n == sizeof(fname))
216 return 0;
217 fname[n] = 0;
218 return strtoull(fname, NULL, 10);
219}
220
221int sysfs_set_str(struct sysarray *sra, struct sysdev *dev,
222 char *name, char *val)
223{
224 char fname[50];
225 int n;
226 int fd;
227 sprintf(fname, "/sys/block/%s/md/%s/%s",
228 sra->name, dev?dev->name:"", name);
229 fd = open(fname, O_WRONLY);
230 if (fd < 0)
231 return -1;
232 n = write(fd, val, strlen(val));
233 close(fd);
234 if (n != strlen(val))
235 return -1;
236 return 0;
237}
238
239int sysfs_set_num(struct sysarray *sra, struct sysdev *dev,
240 char *name, unsigned long long val)
241{
242 char valstr[50];
243 sprintf(valstr, "%llu", val);
244 return sysfs_set_str(sra, dev, name, valstr);
245}
246
247int sysfs_get_ll(struct sysarray *sra, struct sysdev *dev,
248 char *name, unsigned long long *val)
249{
250 char fname[50];
251 char buf[50];
252 int n;
253 int fd;
254 char *ep;
255 sprintf(fname, "/sys/block/%s/md/%s/%s",
256 sra->name, dev?dev->name:"", name);
257 fd = open(fname, O_RDONLY);
258 if (fd < 0)
259 return -1;
260 n = read(fd, buf, sizeof(buf));
261 close(fd);
262 if (n <= 0)
263 return -1;
264 buf[n] = 0;
265 *val = strtoull(buf, &ep, 0);
266 if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
267 return -1;
268 return 0;
269}