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monitor: protect against CONFIG_LBD=n
[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>
1770662b 28#include <ctype.h>
e86c9dd6
NB
29
30int load_sys(char *path, char *buf)
31{
32 int fd = open(path, O_RDONLY);
33 int n;
34 if (fd < 0)
35 return -1;
36 n = read(fd, buf, 1024);
37 close(fd);
2f6079dc 38 if (n <0 || n >= 1024)
e86c9dd6
NB
39 return -1;
40 buf[n] = 0;
8dfb8619 41 if (n && buf[n-1] == '\n')
e86c9dd6
NB
42 buf[n-1] = 0;
43 return 0;
44}
45
7e0f6979 46void sysfs_free(struct mdinfo *sra)
8382f19b 47{
7e0f6979
NB
48 while (sra) {
49 struct mdinfo *sra2 = sra->next;
50 while (sra->devs) {
51 struct mdinfo *d = sra->devs;
52 sra->devs = d->next;
53 free(d);
54 }
55 free(sra);
56 sra = sra2;
8382f19b 57 }
8382f19b
NB
58}
59
549e9569
NB
60int sysfs_open(int devnum, char *devname, char *attr)
61{
62 char fname[50];
549e9569 63 int fd;
549e9569 64
77472ff8 65 sprintf(fname, "/sys/block/%s/md/", devnum2devname(devnum));
549e9569
NB
66 if (devname) {
67 strcat(fname, devname);
68 strcat(fname, "/");
69 }
70 strcat(fname, attr);
71 fd = open(fname, O_RDWR);
ea6d09b0 72 if (fd < 0 && errno == EACCES)
549e9569
NB
73 fd = open(fname, O_RDONLY);
74 return fd;
75}
76
f35f2525
N
77void sysfs_init(struct mdinfo *mdi, int fd, int devnum)
78{
79 if (fd >= 0) {
80 struct stat stb;
81 mdu_version_t vers;
82 if (fstat(fd, &stb))
83 return;
84 if (ioctl(fd, RAID_VERSION, &vers) != 0)
85 return;
86 if (major(stb.st_rdev)==9)
87 sprintf(mdi->sys_name, "md%d", (int)minor(stb.st_rdev));
88 else
89 sprintf(mdi->sys_name, "md_d%d",
90 (int)minor(stb.st_rdev)>>MdpMinorShift);
91 } else {
92 if (devnum >= 0)
93 sprintf(mdi->sys_name, "md%d", devnum);
94 else
95 sprintf(mdi->sys_name, "md_d%d",
96 -1-devnum);
97 }
98}
99
7e0f6979 100struct mdinfo *sysfs_read(int fd, int devnum, unsigned long options)
e86c9dd6
NB
101{
102 /* Longest possible name in sysfs, mounted at /sys, is
103 * /sys/block/md_dXXX/md/dev-XXXXX/block/dev
104 * /sys/block/md_dXXX/md/metadata_version
105 * which is about 41 characters. 50 should do for now
106 */
107 char fname[50];
108 char buf[1024];
109 char *base;
110 char *dbase;
7e0f6979 111 struct mdinfo *sra;
06c7f68e 112 struct mdinfo *dev;
355726fa 113 DIR *dir = NULL;
e86c9dd6
NB
114 struct dirent *de;
115
116 sra = malloc(sizeof(*sra));
117 if (sra == NULL)
118 return sra;
f35f2525
N
119 memset(sra, 0, sizeof(*sra));
120 sysfs_init(sra, fd, devnum);
e86c9dd6 121
7e0f6979 122 sprintf(fname, "/sys/block/%s/md/", sra->sys_name);
e86c9dd6
NB
123 base = fname + strlen(fname);
124
125 sra->devs = NULL;
8382f19b
NB
126 if (options & GET_VERSION) {
127 strcpy(base, "metadata_version");
128 if (load_sys(fname, buf))
129 goto abort;
294d6f45 130 if (strncmp(buf, "none", 4) == 0) {
7e0f6979
NB
131 sra->array.major_version =
132 sra->array.minor_version = -1;
294d6f45
NB
133 strcpy(sra->text_version, "");
134 } else if (strncmp(buf, "external:", 9) == 0) {
142cb9e1
NB
135 sra->array.major_version = -1;
136 sra->array.minor_version = -2;
137 strcpy(sra->text_version, buf+9);
b8ac1967 138 } else {
8382f19b 139 sscanf(buf, "%d.%d",
7e0f6979
NB
140 &sra->array.major_version,
141 &sra->array.minor_version);
b8ac1967
NB
142 strcpy(sra->text_version, buf);
143 }
8382f19b 144 }
e86c9dd6
NB
145 if (options & GET_LEVEL) {
146 strcpy(base, "level");
147 if (load_sys(fname, buf))
148 goto abort;
7e0f6979 149 sra->array.level = map_name(pers, buf);
e86c9dd6
NB
150 }
151 if (options & GET_LAYOUT) {
152 strcpy(base, "layout");
153 if (load_sys(fname, buf))
154 goto abort;
7e0f6979 155 sra->array.layout = strtoul(buf, NULL, 0);
e86c9dd6 156 }
549e9569
NB
157 if (options & GET_DISKS) {
158 strcpy(base, "raid_disks");
159 if (load_sys(fname, buf))
160 goto abort;
161 sra->array.raid_disks = strtoul(buf, NULL, 0);
f1d26766
DW
162 }
163 if (options & GET_DEGRADED) {
164 strcpy(base, "degraded");
165 if (load_sys(fname, buf))
166 goto abort;
167 sra->array.failed_disks = strtoul(buf, NULL, 0);
549e9569 168 }
e86c9dd6
NB
169 if (options & GET_COMPONENT) {
170 strcpy(base, "component_size");
171 if (load_sys(fname, buf))
172 goto abort;
173 sra->component_size = strtoull(buf, NULL, 0);
353632d9
NB
174 /* sysfs reports "K", but we want sectors */
175 sra->component_size *= 2;
e86c9dd6
NB
176 }
177 if (options & GET_CHUNK) {
178 strcpy(base, "chunk_size");
179 if (load_sys(fname, buf))
180 goto abort;
7e0f6979 181 sra->array.chunk_size = strtoul(buf, NULL, 0);
e86c9dd6 182 }
758d3a8e
NB
183 if (options & GET_CACHE) {
184 strcpy(base, "stripe_cache_size");
185 if (load_sys(fname, buf))
186 goto abort;
187 sra->cache_size = strtoul(buf, NULL, 0);
188 }
37dfc3d6
NB
189 if (options & GET_MISMATCH) {
190 strcpy(base, "mismatch_cnt");
191 if (load_sys(fname, buf))
192 goto abort;
193 sra->mismatch_cnt = strtoul(buf, NULL, 0);
194 }
1770662b
DW
195 if (options & GET_SAFEMODE) {
196 int scale = 1;
197 int dot = 0;
198 int i;
199 unsigned long msec;
200 size_t len;
201
202 strcpy(base, "safe_mode_delay");
203 if (load_sys(fname, buf))
204 goto abort;
205
206 /* remove a period, and count digits after it */
207 len = strlen(buf);
208 for (i = 0; i < len; i++) {
209 if (dot) {
210 if (isdigit(buf[i])) {
211 buf[i-1] = buf[i];
212 scale *= 10;
213 }
214 buf[i] = 0;
215 } else if (buf[i] == '.') {
216 dot=1;
217 buf[i] = 0;
218 }
219 }
220 msec = strtoul(buf, NULL, 10);
221 msec = (msec * 1000) / scale;
222 sra->safe_mode_delay = msec;
223 }
e86c9dd6
NB
224
225 if (! (options & GET_DEVS))
226 return sra;
227
228 /* Get all the devices as well */
229 *base = 0;
230 dir = opendir(fname);
231 if (!dir)
232 goto abort;
7e0f6979 233 sra->array.spare_disks = 0;
e86c9dd6
NB
234
235 while ((de = readdir(dir)) != NULL) {
236 char *ep;
237 if (de->d_ino == 0 ||
238 strncmp(de->d_name, "dev-", 4) != 0)
239 continue;
240 strcpy(base, de->d_name);
241 dbase = base + strlen(base);
242 *dbase++ = '/';
243
244 dev = malloc(sizeof(*dev));
245 if (!dev)
246 goto abort;
e86c9dd6
NB
247
248 /* Always get slot, major, minor */
249 strcpy(dbase, "slot");
4795982e
DW
250 if (load_sys(fname, buf)) {
251 /* hmm... unable to read 'slot' maybe the device
252 * is going away?
253 */
254 strcpy(dbase, "block");
255 if (readlink(fname, buf, sizeof(buf)) < 0 &&
256 errno != ENAMETOOLONG) {
257 /* ...yup device is gone */
258 free(dev);
259 continue;
260 } else {
261 /* slot is unreadable but 'block' link
262 * still intact... something bad is happening
263 * so abort
264 */
265 free(dev);
266 goto abort;
267 }
268
269 }
270 dev->next = sra->devs;
271 sra->devs = dev;
272
273 strcpy(dev->sys_name, de->d_name);
06c7f68e
NB
274 dev->disk.raid_disk = strtoul(buf, &ep, 10);
275 if (*ep) dev->disk.raid_disk = -1;
e86c9dd6
NB
276
277 strcpy(dbase, "block/dev");
278 if (load_sys(fname, buf))
279 goto abort;
06c7f68e 280 sscanf(buf, "%d:%d", &dev->disk.major, &dev->disk.minor);
e86c9dd6
NB
281
282 if (options & GET_OFFSET) {
283 strcpy(dbase, "offset");
284 if (load_sys(fname, buf))
285 goto abort;
06c7f68e 286 dev->data_offset = strtoull(buf, NULL, 0);
e86c9dd6
NB
287 }
288 if (options & GET_SIZE) {
289 strcpy(dbase, "size");
290 if (load_sys(fname, buf))
291 goto abort;
047d2e49 292 dev->component_size = strtoull(buf, NULL, 0) * 2;
e86c9dd6
NB
293 }
294 if (options & GET_STATE) {
06c7f68e 295 dev->disk.state = 0;
e86c9dd6
NB
296 strcpy(dbase, "state");
297 if (load_sys(fname, buf))
298 goto abort;
299 if (strstr(buf, "in_sync"))
06c7f68e 300 dev->disk.state |= (1<<MD_DISK_SYNC);
e86c9dd6 301 if (strstr(buf, "faulty"))
06c7f68e
NB
302 dev->disk.state |= (1<<MD_DISK_FAULTY);
303 if (dev->disk.state == 0)
7e0f6979 304 sra->array.spare_disks++;
e86c9dd6
NB
305 }
306 if (options & GET_ERROR) {
307 strcpy(buf, "errors");
308 if (load_sys(fname, buf))
309 goto abort;
310 dev->errors = strtoul(buf, NULL, 0);
311 }
312 }
355726fa 313 closedir(dir);
e86c9dd6
NB
314 return sra;
315
316 abort:
355726fa
NB
317 if (dir)
318 closedir(dir);
8382f19b 319 sysfs_free(sra);
e86c9dd6
NB
320 return NULL;
321}
322
1770662b
DW
323int sysfs_attr_match(const char *attr, const char *str)
324{
325 /* See if attr, read from a sysfs file, matches
326 * str. They must either be the same, or attr can
327 * have a trailing newline or comma
328 */
329 while (*attr && *str && *attr == *str) {
330 attr++;
331 str++;
332 }
333
334 if (*str || (*attr && *attr != ',' && *attr != '\n'))
335 return 0;
336 return 1;
337}
338
339int sysfs_match_word(const char *word, char **list)
340{
341 int n;
342 for (n=0; list[n]; n++)
343 if (sysfs_attr_match(word, list[n]))
344 break;
345 return n;
346}
347
e86c9dd6
NB
348unsigned long long get_component_size(int fd)
349{
350 /* Find out the component size of the array.
351 * We cannot trust GET_ARRAY_INFO ioctl as it's
352 * size field is only 32bits.
353 * So look in /sys/block/mdXXX/md/component_size
353632d9 354 *
8686f3ed 355 * This returns in units of sectors.
e86c9dd6
NB
356 */
357 struct stat stb;
358 char fname[50];
359 int n;
360 if (fstat(fd, &stb)) return 0;
361 if (major(stb.st_rdev) == 9)
362 sprintf(fname, "/sys/block/md%d/md/component_size",
ea24acd0 363 (int)minor(stb.st_rdev));
e86c9dd6
NB
364 else
365 sprintf(fname, "/sys/block/md_d%d/md/component_size",
ea24acd0 366 (int)minor(stb.st_rdev)>>MdpMinorShift);
e86c9dd6
NB
367 fd = open(fname, O_RDONLY);
368 if (fd < 0)
369 return 0;
370 n = read(fd, fname, sizeof(fname));
371 close(fd);
372 if (n == sizeof(fname))
373 return 0;
374 fname[n] = 0;
8686f3ed 375 return strtoull(fname, NULL, 10) * 2;
e86c9dd6
NB
376}
377
7e0f6979 378int sysfs_set_str(struct mdinfo *sra, struct mdinfo *dev,
e86c9dd6
NB
379 char *name, char *val)
380{
381 char fname[50];
382 int n;
383 int fd;
7e1432fb 384
e86c9dd6 385 sprintf(fname, "/sys/block/%s/md/%s/%s",
7e0f6979 386 sra->sys_name, dev?dev->sys_name:"", name);
e86c9dd6
NB
387 fd = open(fname, O_WRONLY);
388 if (fd < 0)
389 return -1;
390 n = write(fd, val, strlen(val));
391 close(fd);
2a24d7b6
DW
392 if (n != strlen(val)) {
393 dprintf(Name ": failed to write '%s' to '%s' (%s)\n",
394 val, fname, strerror(errno));
e86c9dd6 395 return -1;
2a24d7b6 396 }
e86c9dd6
NB
397 return 0;
398}
399
7e0f6979 400int sysfs_set_num(struct mdinfo *sra, struct mdinfo *dev,
e86c9dd6
NB
401 char *name, unsigned long long val)
402{
403 char valstr[50];
404 sprintf(valstr, "%llu", val);
405 return sysfs_set_str(sra, dev, name, valstr);
406}
407
7e0f6979 408int sysfs_get_ll(struct mdinfo *sra, struct mdinfo *dev,
e86c9dd6
NB
409 char *name, unsigned long long *val)
410{
411 char fname[50];
412 char buf[50];
413 int n;
414 int fd;
415 char *ep;
416 sprintf(fname, "/sys/block/%s/md/%s/%s",
7e0f6979 417 sra->sys_name, dev?dev->sys_name:"", name);
e86c9dd6
NB
418 fd = open(fname, O_RDONLY);
419 if (fd < 0)
420 return -1;
421 n = read(fd, buf, sizeof(buf));
422 close(fd);
423 if (n <= 0)
424 return -1;
425 buf[n] = 0;
426 *val = strtoull(buf, &ep, 0);
427 if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
428 return -1;
429 return 0;
430}
2503d23b 431
8ed3e5e1
DW
432int sysfs_set_safemode(struct mdinfo *sra, unsigned long ms)
433{
434 unsigned long sec;
435 unsigned long msec;
436 char delay[30];
437
438 sec = ms / 1000;
439 msec = ms - (sec * 1000);
440
441 sprintf(delay, "%ld.%ld", sec, msec);
442 return sysfs_set_str(sra, NULL, "safe_mode_delay", delay);
443}
444
f35f2525 445int sysfs_set_array(struct mdinfo *info, int vers)
2503d23b
NB
446{
447 int rv = 0;
f35f2525
N
448 char ver[100];
449
450 ver[0] = 0;
451 if (info->array.major_version == -1 &&
452 info->array.minor_version == -2) {
453 strcat(strcpy(ver, "external:"), info->text_version);
454
455 if ((vers % 100) < 2 ||
456 sysfs_set_str(info, NULL, "metadata_version",
457 ver) < 0) {
458 fprintf(stderr, Name ": This kernel does not "
459 "support external metadata.\n");
460 return 1;
461 }
462 }
2503d23b
NB
463 if (info->array.level < 0)
464 return 0; /* FIXME */
f35f2525 465 rv |= sysfs_set_str(info, NULL, "level",
2503d23b 466 map_num(pers, info->array.level));
f35f2525
N
467 rv |= sysfs_set_num(info, NULL, "raid_disks", info->array.raid_disks);
468 rv |= sysfs_set_num(info, NULL, "chunk_size", info->array.chunk_size);
469 rv |= sysfs_set_num(info, NULL, "layout", info->array.layout);
470 rv |= sysfs_set_num(info, NULL, "component_size", info->component_size/2);
471 if (info->array.level > 0)
472 rv |= sysfs_set_num(info, NULL, "resync_start", info->resync_start);
2503d23b
NB
473 return rv;
474}
475
2318b9f0 476int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd)
2503d23b
NB
477{
478 char dv[100];
479 char nm[100];
2503d23b
NB
480 char *dname;
481 int rv;
482
483 sprintf(dv, "%d:%d", sd->disk.major, sd->disk.minor);
484 rv = sysfs_set_str(sra, NULL, "new_dev", dv);
485 if (rv)
486 return rv;
487
488 memset(nm, 0, sizeof(nm));
489 sprintf(dv, "/sys/dev/block/%d:%d", sd->disk.major, sd->disk.minor);
73649188
N
490 rv = readlink(dv, nm, sizeof(nm));
491 if (rv <= 0)
2503d23b 492 return -1;
73649188 493 nm[rv] = '\0';
2503d23b
NB
494 dname = strrchr(nm, '/');
495 if (dname) dname++;
496 strcpy(sd->sys_name, "dev-");
497 strcpy(sd->sys_name+4, dname);
498
73649188 499 rv = sysfs_set_num(sra, sd, "offset", sd->data_offset);
2503d23b
NB
500 rv |= sysfs_set_num(sra, sd, "size", (sd->component_size+1) / 2);
501 if (sra->array.level != LEVEL_CONTAINER) {
502 rv |= sysfs_set_num(sra, sd, "slot", sd->disk.raid_disk);
503// rv |= sysfs_set_str(sra, sd, "state", "in_sync");
504 }
2503d23b
NB
505 return rv;
506}
90c8b707 507
755c99fa 508#if 0
90c8b707
DW
509int sysfs_disk_to_sg(int fd)
510{
511 /* from an open block device, try find and open its corresponding
512 * scsi_generic interface
513 */
514 struct stat st;
515 char path[256];
516 char sg_path[256];
517 char sg_major_minor[8];
518 char *c;
519 DIR *dir;
520 struct dirent *de;
521 int major, minor, rv;
522
523 if (fstat(fd, &st))
524 return -1;
525
526 snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/device",
527 major(st.st_rdev), minor(st.st_rdev));
528
529 dir = opendir(path);
530 if (!dir)
531 return -1;
532
533 de = readdir(dir);
534 while (de) {
535 if (strncmp("scsi_generic:", de->d_name,
536 strlen("scsi_generic:")) == 0)
537 break;
538 de = readdir(dir);
539 }
540 closedir(dir);
541
542 if (!de)
543 return -1;
544
545 snprintf(sg_path, sizeof(sg_path), "%s/%s/dev", path, de->d_name);
546 fd = open(sg_path, O_RDONLY);
547 if (fd < 0)
548 return fd;
549
550 rv = read(fd, sg_major_minor, sizeof(sg_major_minor));
551 close(fd);
552 if (rv < 0)
553 return -1;
554 else
555 sg_major_minor[rv - 1] = '\0';
556
557 c = strchr(sg_major_minor, ':');
558 *c = '\0';
559 c++;
560 major = strtol(sg_major_minor, NULL, 10);
561 minor = strtol(c, NULL, 10);
562 snprintf(path, sizeof(path), "/dev/.tmp.md.%d:%d:%d",
563 (int) getpid(), major, minor);
564 if (mknod(path, S_IFCHR|0600, makedev(major, minor))==0) {
565 fd = open(path, O_RDONLY);
566 unlink(path);
567 return fd;
568 }
569
570 return -1;
571}
755c99fa 572#endif
90c8b707 573
f1665f72
DW
574int sysfs_disk_to_scsi_id(int fd, __u32 *id)
575{
576 /* from an open block device, try to retrieve it scsi_id */
577 struct stat st;
578 char path[256];
579 char *c1, *c2;
580 DIR *dir;
581 struct dirent *de;
582
583 if (fstat(fd, &st))
584 return 1;
585
586 snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/device",
587 major(st.st_rdev), minor(st.st_rdev));
588
589 dir = opendir(path);
590 if (!dir)
591 return 1;
592
593 de = readdir(dir);
594 while (de) {
595 if (strncmp("scsi_disk:", de->d_name,
596 strlen("scsi_disk:")) == 0)
597 break;
598 de = readdir(dir);
599 }
600 closedir(dir);
601
602 if (!de)
603 return 1;
604
605 c1 = strchr(de->d_name, ':');
606 c1++;
607 c2 = strchr(c1, ':');
608 *c2 = '\0';
609 *id = strtol(c1, NULL, 10) << 24; /* host */
610 c1 = c2 + 1;
611 c2 = strchr(c1, ':');
612 *c2 = '\0';
613 *id |= strtol(c1, NULL, 10) << 16; /* channel */
614 c1 = c2 + 1;
615 c2 = strchr(c1, ':');
616 *c2 = '\0';
617 *id |= strtol(c1, NULL, 10) << 8; /* lun */
618 c1 = c2 + 1;
619 *id |= strtol(c1, NULL, 10); /* id */
620
621 return 0;
622}
f94d52f4
NB
623
624
625int sysfs_unique_holder(int devnum, long rdev)
626{
627 /* Check that devnum is a holder of rdev,
628 * and is the only holder.
629 * we should be locked against races by
630 * an O_EXCL on devnum
631 */
632 DIR *dir;
633 struct dirent *de;
634 char dirname[100];
635 char l;
636 int found = 0;
637 sprintf(dirname, "/sys/dev/block/%d:%d/holders",
638 major(rdev), minor(rdev));
639 dir = opendir(dirname);
640 errno = ENOENT;
641 if (!dir)
642 return 0;
643 l = strlen(dirname);
644 while ((de = readdir(dir)) != NULL) {
645 char buf[10];
646 int n;
647 int mj, mn;
648 char c;
649 int fd;
650
651 if (de->d_ino == 0)
652 continue;
653 if (de->d_name[0] == '.')
654 continue;
655 strcpy(dirname+l, "/");
656 strcat(dirname+l, de->d_name);
657 strcat(dirname+l, "/dev");
658 fd = open(dirname, O_RDONLY);
659 if (fd < 0) {
660 errno = ENOENT;
661 break;
662 }
663 n = read(fd, buf, sizeof(buf)-1);
664 close(fd);
665 buf[n] = 0;
666 if (sscanf(buf, "%d:%d%c", &mj, &mn, &c) != 3 ||
667 c != '\n') {
668 errno = ENOENT;
669 break;
670 }
671 if (mj != MD_MAJOR)
672 mn = -1-(mn>>6);
673
674 if (devnum != mn) {
675 errno = EEXIST;
676 break;
677 }
678 found = 1;
679 }
680 closedir(dir);
681 if (de)
682 return 0;
683 else
684 return found;
685}