]>
git.ipfire.org Git - thirdparty/mdadm.git/blob - sysfs.c
2 * sysfs - extract md related information from sysfs. Part of:
3 * mdadm - manage Linux "md" devices aka RAID arrays.
5 * Copyright (C) 2006 Neil Brown <neilb@suse.de>
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.
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.
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
23 * Email: <neilb@suse.de>
29 int load_sys(char *path
, char *buf
)
31 int fd
= open(path
, O_RDONLY
);
35 n
= read(fd
, buf
, 1024);
37 if (n
<0 || n
>= 1024)
45 void sysfs_free(struct mdinfo
*sra
)
48 struct mdinfo
*sra2
= sra
->next
;
50 struct mdinfo
*d
= sra
->devs
;
59 int sysfs_open(int devnum
, char *devname
, char *attr
)
65 sprintf(sys_name
, "md%d", devnum
);
67 sprintf(sys_name
, "md_d%d",
70 sprintf(fname
, "/sys/block/%s/md/", sys_name
);
72 strcat(fname
, devname
);
76 fd
= open(fname
, O_RDWR
);
77 if (fd
< 0 && errno
== EACCES
)
78 fd
= open(fname
, O_RDONLY
);
82 struct mdinfo
*sysfs_read(int fd
, int devnum
, unsigned long options
)
84 /* Longest possible name in sysfs, mounted at /sys, is
85 * /sys/block/md_dXXX/md/dev-XXXXX/block/dev
86 * /sys/block/md_dXXX/md/metadata_version
87 * which is about 41 characters. 50 should do for now
98 sra
= malloc(sizeof(*sra
));
106 if (fstat(fd
, &stb
)) return NULL
;
107 if (ioctl(fd
, RAID_VERSION
, &vers
) != 0)
109 if (major(stb
.st_rdev
)==9)
110 sprintf(sra
->sys_name
, "md%d", (int)minor(stb
.st_rdev
));
112 sprintf(sra
->sys_name
, "md_d%d",
113 (int)minor(stb
.st_rdev
)>>MdpMinorShift
);
116 sprintf(sra
->sys_name
, "md%d", devnum
);
118 sprintf(sra
->sys_name
, "md_d%d",
121 sprintf(fname
, "/sys/block/%s/md/", sra
->sys_name
);
122 base
= fname
+ strlen(fname
);
125 if (options
& GET_VERSION
) {
126 strcpy(base
, "metadata_version");
127 if (load_sys(fname
, buf
))
129 if (strncmp(buf
, "none", 4) == 0) {
130 sra
->array
.major_version
=
131 sra
->array
.minor_version
= -1;
132 strcpy(sra
->text_version
, "");
133 } else if (strncmp(buf
, "external:", 9) == 0) {
134 sra
->array
.major_version
= -1;
135 sra
->array
.minor_version
= -2;
136 strcpy(sra
->text_version
, buf
+9);
139 &sra
->array
.major_version
,
140 &sra
->array
.minor_version
);
141 strcpy(sra
->text_version
, buf
);
144 if (options
& GET_LEVEL
) {
145 strcpy(base
, "level");
146 if (load_sys(fname
, buf
))
148 sra
->array
.level
= map_name(pers
, buf
);
150 if (options
& GET_LAYOUT
) {
151 strcpy(base
, "layout");
152 if (load_sys(fname
, buf
))
154 sra
->array
.layout
= strtoul(buf
, NULL
, 0);
156 if (options
& GET_DISKS
) {
157 strcpy(base
, "raid_disks");
158 if (load_sys(fname
, buf
))
160 sra
->array
.raid_disks
= strtoul(buf
, NULL
, 0);
162 if (options
& GET_COMPONENT
) {
163 strcpy(base
, "component_size");
164 if (load_sys(fname
, buf
))
166 sra
->component_size
= strtoull(buf
, NULL
, 0);
167 /* sysfs reports "K", but we want sectors */
168 sra
->component_size
*= 2;
170 if (options
& GET_CHUNK
) {
171 strcpy(base
, "chunk_size");
172 if (load_sys(fname
, buf
))
174 sra
->array
.chunk_size
= strtoul(buf
, NULL
, 0);
176 if (options
& GET_CACHE
) {
177 strcpy(base
, "stripe_cache_size");
178 if (load_sys(fname
, buf
))
180 sra
->cache_size
= strtoul(buf
, NULL
, 0);
182 if (options
& GET_MISMATCH
) {
183 strcpy(base
, "mismatch_cnt");
184 if (load_sys(fname
, buf
))
186 sra
->mismatch_cnt
= strtoul(buf
, NULL
, 0);
189 if (! (options
& GET_DEVS
))
192 /* Get all the devices as well */
194 dir
= opendir(fname
);
197 sra
->array
.spare_disks
= 0;
199 while ((de
= readdir(dir
)) != NULL
) {
201 if (de
->d_ino
== 0 ||
202 strncmp(de
->d_name
, "dev-", 4) != 0)
204 strcpy(base
, de
->d_name
);
205 dbase
= base
+ strlen(base
);
208 dev
= malloc(sizeof(*dev
));
211 dev
->next
= sra
->devs
;
213 strcpy(dev
->sys_name
, de
->d_name
);
215 /* Always get slot, major, minor */
216 strcpy(dbase
, "slot");
217 if (load_sys(fname
, buf
))
219 dev
->disk
.raid_disk
= strtoul(buf
, &ep
, 10);
220 if (*ep
) dev
->disk
.raid_disk
= -1;
222 strcpy(dbase
, "block/dev");
223 if (load_sys(fname
, buf
))
225 sscanf(buf
, "%d:%d", &dev
->disk
.major
, &dev
->disk
.minor
);
227 if (options
& GET_OFFSET
) {
228 strcpy(dbase
, "offset");
229 if (load_sys(fname
, buf
))
231 dev
->data_offset
= strtoull(buf
, NULL
, 0);
233 if (options
& GET_SIZE
) {
234 strcpy(dbase
, "size");
235 if (load_sys(fname
, buf
))
237 dev
->component_size
= strtoull(buf
, NULL
, 0);
239 if (options
& GET_STATE
) {
241 strcpy(dbase
, "state");
242 if (load_sys(fname
, buf
))
244 if (strstr(buf
, "in_sync"))
245 dev
->disk
.state
|= (1<<MD_DISK_SYNC
);
246 if (strstr(buf
, "faulty"))
247 dev
->disk
.state
|= (1<<MD_DISK_FAULTY
);
248 if (dev
->disk
.state
== 0)
249 sra
->array
.spare_disks
++;
251 if (options
& GET_ERROR
) {
252 strcpy(buf
, "errors");
253 if (load_sys(fname
, buf
))
255 dev
->errors
= strtoul(buf
, NULL
, 0);
268 unsigned long long get_component_size(int fd
)
270 /* Find out the component size of the array.
271 * We cannot trust GET_ARRAY_INFO ioctl as it's
272 * size field is only 32bits.
273 * So look in /sys/block/mdXXX/md/component_size
275 * This returns in units of sectors.
280 if (fstat(fd
, &stb
)) return 0;
281 if (major(stb
.st_rdev
) == 9)
282 sprintf(fname
, "/sys/block/md%d/md/component_size",
283 (int)minor(stb
.st_rdev
));
285 sprintf(fname
, "/sys/block/md_d%d/md/component_size",
286 (int)minor(stb
.st_rdev
)>>MdpMinorShift
);
287 fd
= open(fname
, O_RDONLY
);
290 n
= read(fd
, fname
, sizeof(fname
));
292 if (n
== sizeof(fname
))
295 return strtoull(fname
, NULL
, 10) * 2;
298 int sysfs_set_str(struct mdinfo
*sra
, struct mdinfo
*dev
,
299 char *name
, char *val
)
305 sprintf(fname
, "/sys/block/%s/md/%s/%s",
306 sra
->sys_name
, dev
?dev
->sys_name
:"", name
);
307 fd
= open(fname
, O_WRONLY
);
310 n
= write(fd
, val
, strlen(val
));
312 if (n
!= strlen(val
))
317 int sysfs_set_num(struct mdinfo
*sra
, struct mdinfo
*dev
,
318 char *name
, unsigned long long val
)
321 sprintf(valstr
, "%llu", val
);
322 return sysfs_set_str(sra
, dev
, name
, valstr
);
325 int sysfs_get_ll(struct mdinfo
*sra
, struct mdinfo
*dev
,
326 char *name
, unsigned long long *val
)
333 sprintf(fname
, "/sys/block/%s/md/%s/%s",
334 sra
->sys_name
, dev
?dev
->sys_name
:"", name
);
335 fd
= open(fname
, O_RDONLY
);
338 n
= read(fd
, buf
, sizeof(buf
));
343 *val
= strtoull(buf
, &ep
, 0);
344 if (ep
== buf
|| (*ep
!= 0 && *ep
!= '\n' && *ep
!= ' '))
349 int sysfs_set_array(struct mdinfo
*sra
,
353 sra
->array
= info
->array
;
355 if (info
->array
.level
< 0)
356 return 0; /* FIXME */
357 rv
|= sysfs_set_str(sra
, NULL
, "level",
358 map_num(pers
, info
->array
.level
));
359 rv
|= sysfs_set_num(sra
, NULL
, "raid_disks", info
->array
.raid_disks
);
360 rv
|= sysfs_set_num(sra
, NULL
, "chunk_size", info
->array
.chunk_size
);
361 rv
|= sysfs_set_num(sra
, NULL
, "layout", info
->array
.layout
);
362 rv
|= sysfs_set_num(sra
, NULL
, "component_size", info
->component_size
);
363 rv
|= sysfs_set_num(sra
, NULL
, "resync_start", info
->resync_start
);
364 sra
->array
= info
->array
;
368 int sysfs_add_disk(struct mdinfo
*sra
, struct mdinfo
*sd
)
376 sprintf(dv
, "%d:%d", sd
->disk
.major
, sd
->disk
.minor
);
377 rv
= sysfs_set_str(sra
, NULL
, "new_dev", dv
);
381 memset(nm
, 0, sizeof(nm
));
382 sprintf(dv
, "/sys/dev/block/%d:%d", sd
->disk
.major
, sd
->disk
.minor
);
383 if (readlink(dv
, nm
, sizeof(nm
)) < 0)
385 dname
= strrchr(nm
, '/');
387 strcpy(sd
->sys_name
, "dev-");
388 strcpy(sd
->sys_name
+4, dname
);
390 rv
|= sysfs_set_num(sra
, sd
, "offset", sd
->data_offset
);
391 rv
|= sysfs_set_num(sra
, sd
, "size", (sd
->component_size
+1) / 2);
392 if (sra
->array
.level
!= LEVEL_CONTAINER
) {
393 rv
|= sysfs_set_num(sra
, sd
, "slot", sd
->disk
.raid_disk
);
394 // rv |= sysfs_set_str(sra, sd, "state", "in_sync");
397 sd2
= malloc(sizeof(*sd2
));
399 sd2
->next
= sra
->devs
;
405 int sysfs_disk_to_sg(int fd
)
407 /* from an open block device, try find and open its corresponding
408 * scsi_generic interface
413 char sg_major_minor
[8];
417 int major
, minor
, rv
;
422 snprintf(path
, sizeof(path
), "/sys/dev/block/%d:%d/device",
423 major(st
.st_rdev
), minor(st
.st_rdev
));
431 if (strncmp("scsi_generic:", de
->d_name
,
432 strlen("scsi_generic:")) == 0)
441 snprintf(sg_path
, sizeof(sg_path
), "%s/%s/dev", path
, de
->d_name
);
442 fd
= open(sg_path
, O_RDONLY
);
446 rv
= read(fd
, sg_major_minor
, sizeof(sg_major_minor
));
451 sg_major_minor
[rv
- 1] = '\0';
453 c
= strchr(sg_major_minor
, ':');
456 major
= strtol(sg_major_minor
, NULL
, 10);
457 minor
= strtol(c
, NULL
, 10);
458 snprintf(path
, sizeof(path
), "/dev/.tmp.md.%d:%d:%d",
459 (int) getpid(), major
, minor
);
460 if (mknod(path
, S_IFCHR
|0600, makedev(major
, minor
))==0) {
461 fd
= open(path
, O_RDONLY
);
469 int sysfs_disk_to_scsi_id(int fd
, __u32
*id
)
471 /* from an open block device, try to retrieve it scsi_id */
481 snprintf(path
, sizeof(path
), "/sys/dev/block/%d:%d/device",
482 major(st
.st_rdev
), minor(st
.st_rdev
));
490 if (strncmp("scsi_disk:", de
->d_name
,
491 strlen("scsi_disk:")) == 0)
500 c1
= strchr(de
->d_name
, ':');
502 c2
= strchr(c1
, ':');
504 *id
= strtol(c1
, NULL
, 10) << 24; /* host */
506 c2
= strchr(c1
, ':');
508 *id
|= strtol(c1
, NULL
, 10) << 16; /* channel */
510 c2
= strchr(c1
, ':');
512 *id
|= strtol(c1
, NULL
, 10) << 8; /* lun */
514 *id
|= strtol(c1
, NULL
, 10); /* id */
520 int sysfs_unique_holder(int devnum
, long rdev
)
522 /* Check that devnum is a holder of rdev,
523 * and is the only holder.
524 * we should be locked against races by
525 * an O_EXCL on devnum
532 sprintf(dirname
, "/sys/dev/block/%d:%d/holders",
533 major(rdev
), minor(rdev
));
534 dir
= opendir(dirname
);
539 while ((de
= readdir(dir
)) != NULL
) {
548 if (de
->d_name
[0] == '.')
550 strcpy(dirname
+l
, "/");
551 strcat(dirname
+l
, de
->d_name
);
552 strcat(dirname
+l
, "/dev");
553 fd
= open(dirname
, O_RDONLY
);
558 n
= read(fd
, buf
, sizeof(buf
)-1);
561 if (sscanf(buf
, "%d:%d%c", &mj
, &mn
, &c
) != 3 ||