2 * sysfs - extract md related information from sysfs. Part of:
3 * mdadm - manage Linux "md" devices aka RAID arrays.
5 * Copyright (C) 2006-2009 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>
30 #define MAX_SYSFS_PATH_LEN 120
32 int load_sys(char *path
, char *buf
, int len
)
34 int fd
= open(path
, O_RDONLY
);
38 n
= read(fd
, buf
, len
);
43 if (n
&& buf
[n
-1] == '\n')
48 void sysfs_free(struct mdinfo
*sra
)
51 struct mdinfo
*sra2
= sra
->next
;
53 struct mdinfo
*d
= sra
->devs
;
58 free(sra
->bb
.entries
);
64 int sysfs_open(char *devnm
, char *devname
, char *attr
)
66 char fname
[MAX_SYSFS_PATH_LEN
];
69 snprintf(fname
, MAX_SYSFS_PATH_LEN
, "/sys/block/%s/md/", devnm
);
71 strncat(fname
, devname
, MAX_SYSFS_PATH_LEN
- strlen(fname
));
72 strncat(fname
, "/", MAX_SYSFS_PATH_LEN
- strlen(fname
));
74 strncat(fname
, attr
, MAX_SYSFS_PATH_LEN
- strlen(fname
));
75 fd
= open(fname
, O_RDWR
);
76 if (fd
< 0 && errno
== EACCES
)
77 fd
= open(fname
, O_RDONLY
);
81 void sysfs_init_dev(struct mdinfo
*mdi
, unsigned long devid
)
83 snprintf(mdi
->sys_name
,
84 sizeof(mdi
->sys_name
), "dev-%s", devid2kname(devid
));
87 int sysfs_init(struct mdinfo
*mdi
, int fd
, char *devnm
)
90 char fname
[MAX_SYSFS_PATH_LEN
];
100 snprintf(fname
, MAX_SYSFS_PATH_LEN
, "/sys/block/%s/md", devnm
);
102 if (stat(fname
, &stb
))
104 if (!S_ISDIR(stb
.st_mode
))
106 strcpy(mdi
->sys_name
, devnm
);
113 struct mdinfo
*sysfs_read(int fd
, char *devnm
, unsigned long options
)
115 char fname
[PATH_MAX
];
120 struct mdinfo
*dev
, **devp
;
124 sra
= xcalloc(1, sizeof(*sra
));
125 if (sysfs_init(sra
, fd
, devnm
)) {
130 sprintf(fname
, "/sys/block/%s/md/", sra
->sys_name
);
131 base
= fname
+ strlen(fname
);
134 if (options
& GET_VERSION
) {
135 strcpy(base
, "metadata_version");
136 if (load_sys(fname
, buf
, sizeof(buf
)))
138 if (strncmp(buf
, "none", 4) == 0) {
139 sra
->array
.major_version
=
140 sra
->array
.minor_version
= -1;
141 strcpy(sra
->text_version
, "");
142 } else if (strncmp(buf
, "external:", 9) == 0) {
143 sra
->array
.major_version
= -1;
144 sra
->array
.minor_version
= -2;
145 strcpy(sra
->text_version
, buf
+9);
148 &sra
->array
.major_version
,
149 &sra
->array
.minor_version
);
150 strcpy(sra
->text_version
, buf
);
153 if (options
& GET_LEVEL
) {
154 strcpy(base
, "level");
155 if (load_sys(fname
, buf
, sizeof(buf
)))
157 sra
->array
.level
= map_name(pers
, buf
);
159 if (options
& GET_LAYOUT
) {
160 strcpy(base
, "layout");
161 if (load_sys(fname
, buf
, sizeof(buf
)))
163 sra
->array
.layout
= strtoul(buf
, NULL
, 0);
165 if (options
& GET_DISKS
) {
166 strcpy(base
, "raid_disks");
167 if (load_sys(fname
, buf
, sizeof(buf
)))
169 sra
->array
.raid_disks
= strtoul(buf
, NULL
, 0);
171 if (options
& GET_DEGRADED
) {
172 strcpy(base
, "degraded");
173 if (load_sys(fname
, buf
, sizeof(buf
)))
175 sra
->array
.failed_disks
= strtoul(buf
, NULL
, 0);
177 if (options
& GET_COMPONENT
) {
178 strcpy(base
, "component_size");
179 if (load_sys(fname
, buf
, sizeof(buf
)))
181 sra
->component_size
= strtoull(buf
, NULL
, 0);
182 /* sysfs reports "K", but we want sectors */
183 sra
->component_size
*= 2;
185 if (options
& GET_CHUNK
) {
186 strcpy(base
, "chunk_size");
187 if (load_sys(fname
, buf
, sizeof(buf
)))
189 sra
->array
.chunk_size
= strtoul(buf
, NULL
, 0);
191 if (options
& GET_CACHE
) {
192 strcpy(base
, "stripe_cache_size");
193 if (load_sys(fname
, buf
, sizeof(buf
)))
194 /* Probably level doesn't support it */
197 sra
->cache_size
= strtoul(buf
, NULL
, 0);
199 if (options
& GET_MISMATCH
) {
200 strcpy(base
, "mismatch_cnt");
201 if (load_sys(fname
, buf
, sizeof(buf
)))
203 sra
->mismatch_cnt
= strtoul(buf
, NULL
, 0);
205 if (options
& GET_SAFEMODE
) {
212 strcpy(base
, "safe_mode_delay");
213 if (load_sys(fname
, buf
, sizeof(buf
)))
216 /* remove a period, and count digits after it */
218 for (i
= 0; i
< len
; i
++) {
220 if (isdigit(buf
[i
])) {
225 } else if (buf
[i
] == '.') {
230 msec
= strtoul(buf
, NULL
, 10);
231 msec
= (msec
* 1000) / scale
;
232 sra
->safe_mode_delay
= msec
;
234 if (options
& GET_BITMAP_LOCATION
) {
235 strcpy(base
, "bitmap/location");
236 if (load_sys(fname
, buf
, sizeof(buf
)))
238 if (strncmp(buf
, "file", 4) == 0)
239 sra
->bitmap_offset
= 1;
240 else if (strncmp(buf
, "none", 4) == 0)
241 sra
->bitmap_offset
= 0;
242 else if (buf
[0] == '+')
243 sra
->bitmap_offset
= strtol(buf
+1, NULL
, 10);
248 if (options
& GET_ARRAY_STATE
) {
249 strcpy(base
, "array_state");
250 if (load_sys(fname
, sra
->sysfs_array_state
,
251 sizeof(sra
->sysfs_array_state
)))
254 sra
->sysfs_array_state
[0] = 0;
256 if (options
& GET_CONSISTENCY_POLICY
) {
257 strcpy(base
, "consistency_policy");
258 if (load_sys(fname
, buf
, sizeof(buf
))) {
259 sra
->consistency_policy
= CONSISTENCY_POLICY_UNKNOWN
;
261 sra
->consistency_policy
= map_name(consistency_policies
, buf
);
262 if (sra
->consistency_policy
== UnSet
)
263 sra
->consistency_policy
= CONSISTENCY_POLICY_UNKNOWN
;
267 if (! (options
& GET_DEVS
))
270 /* Get all the devices as well */
272 dir
= opendir(fname
);
275 sra
->array
.spare_disks
= 0;
279 while ((de
= readdir(dir
)) != NULL
) {
281 if (de
->d_ino
== 0 ||
282 strncmp(de
->d_name
, "dev-", 4) != 0)
284 strcpy(base
, de
->d_name
);
285 dbase
= base
+ strlen(base
);
288 dev
= xcalloc(1, sizeof(*dev
));
290 /* Always get slot, major, minor */
291 strcpy(dbase
, "slot");
292 if (load_sys(fname
, buf
, sizeof(buf
))) {
293 /* hmm... unable to read 'slot' maybe the device
296 strcpy(dbase
, "block");
297 if (readlink(fname
, buf
, sizeof(buf
)) < 0 &&
298 errno
!= ENAMETOOLONG
) {
299 /* ...yup device is gone */
303 /* slot is unreadable but 'block' link
304 * still intact... something bad is happening
312 strcpy(dev
->sys_name
, de
->d_name
);
313 dev
->disk
.raid_disk
= strtoul(buf
, &ep
, 10);
314 if (*ep
) dev
->disk
.raid_disk
= -1;
316 strcpy(dbase
, "block/dev");
317 if (load_sys(fname
, buf
, sizeof(buf
))) {
318 /* assume this is a stale reference to a hot
324 sra
->array
.nr_disks
++;
325 sscanf(buf
, "%d:%d", &dev
->disk
.major
, &dev
->disk
.minor
);
327 /* special case check for block devices that can go 'offline' */
328 strcpy(dbase
, "block/device/state");
329 if (load_sys(fname
, buf
, sizeof(buf
)) == 0 &&
330 strncmp(buf
, "offline", 7) == 0) {
335 /* finally add this disk to the array */
340 if (options
& GET_OFFSET
) {
341 strcpy(dbase
, "offset");
342 if (load_sys(fname
, buf
, sizeof(buf
)))
344 dev
->data_offset
= strtoull(buf
, NULL
, 0);
345 strcpy(dbase
, "new_offset");
346 if (load_sys(fname
, buf
, sizeof(buf
)) == 0)
347 dev
->new_data_offset
= strtoull(buf
, NULL
, 0);
349 dev
->new_data_offset
= dev
->data_offset
;
351 if (options
& GET_SIZE
) {
352 strcpy(dbase
, "size");
353 if (load_sys(fname
, buf
, sizeof(buf
)))
355 dev
->component_size
= strtoull(buf
, NULL
, 0) * 2;
357 if (options
& GET_STATE
) {
359 strcpy(dbase
, "state");
360 if (load_sys(fname
, buf
, sizeof(buf
)))
362 if (strstr(buf
, "in_sync"))
363 dev
->disk
.state
|= (1<<MD_DISK_SYNC
);
364 if (strstr(buf
, "faulty"))
365 dev
->disk
.state
|= (1<<MD_DISK_FAULTY
);
366 if (dev
->disk
.state
== 0)
367 sra
->array
.spare_disks
++;
369 if (options
& GET_ERROR
) {
370 strcpy(buf
, "errors");
371 if (load_sys(fname
, buf
, sizeof(buf
)))
373 dev
->errors
= strtoul(buf
, NULL
, 0);
386 int sysfs_attr_match(const char *attr
, const char *str
)
388 /* See if attr, read from a sysfs file, matches
389 * str. They must either be the same, or attr can
390 * have a trailing newline or comma
392 while (*attr
&& *str
&& *attr
== *str
) {
397 if (*str
|| (*attr
&& *attr
!= ',' && *attr
!= '\n'))
402 int sysfs_match_word(const char *word
, char **list
)
405 for (n
=0; list
[n
]; n
++)
406 if (sysfs_attr_match(word
, list
[n
]))
411 unsigned long long get_component_size(int fd
)
413 /* Find out the component size of the array.
414 * We cannot trust GET_ARRAY_INFO ioctl as it's
415 * size field is only 32bits.
416 * So look in /sys/block/mdXXX/md/component_size
418 * This returns in units of sectors.
421 char fname
[MAX_SYSFS_PATH_LEN
];
425 snprintf(fname
, MAX_SYSFS_PATH_LEN
,
426 "/sys/block/%s/md/component_size", stat2devnm(&stb
));
427 fd
= open(fname
, O_RDONLY
);
430 n
= read(fd
, fname
, sizeof(fname
));
432 if (n
< 0 || n
== sizeof(fname
))
435 return strtoull(fname
, NULL
, 10) * 2;
438 int sysfs_set_str(struct mdinfo
*sra
, struct mdinfo
*dev
,
439 char *name
, char *val
)
441 char fname
[MAX_SYSFS_PATH_LEN
];
445 snprintf(fname
, MAX_SYSFS_PATH_LEN
, "/sys/block/%s/md/%s/%s",
446 sra
->sys_name
, dev
?dev
->sys_name
:"", name
);
447 fd
= open(fname
, O_WRONLY
);
450 n
= write(fd
, val
, strlen(val
));
452 if (n
!= strlen(val
)) {
453 dprintf("failed to write '%s' to '%s' (%s)\n",
454 val
, fname
, strerror(errno
));
460 int sysfs_set_num(struct mdinfo
*sra
, struct mdinfo
*dev
,
461 char *name
, unsigned long long val
)
464 sprintf(valstr
, "%llu", val
);
465 return sysfs_set_str(sra
, dev
, name
, valstr
);
468 int sysfs_set_num_signed(struct mdinfo
*sra
, struct mdinfo
*dev
,
469 char *name
, long long val
)
472 sprintf(valstr
, "%lli", val
);
473 return sysfs_set_str(sra
, dev
, name
, valstr
);
476 int sysfs_uevent(struct mdinfo
*sra
, char *event
)
478 char fname
[MAX_SYSFS_PATH_LEN
];
482 snprintf(fname
, MAX_SYSFS_PATH_LEN
, "/sys/block/%s/uevent",
484 fd
= open(fname
, O_WRONLY
);
487 n
= write(fd
, event
, strlen(event
));
489 if (n
!= (int)strlen(event
)) {
490 dprintf("failed to write '%s' to '%s' (%s)\n",
491 event
, fname
, strerror(errno
));
497 int sysfs_attribute_available(struct mdinfo
*sra
, struct mdinfo
*dev
, char *name
)
499 char fname
[MAX_SYSFS_PATH_LEN
];
502 snprintf(fname
, MAX_SYSFS_PATH_LEN
, "/sys/block/%s/md/%s/%s",
503 sra
->sys_name
, dev
?dev
->sys_name
:"", name
);
505 return stat(fname
, &st
) == 0;
508 int sysfs_get_fd(struct mdinfo
*sra
, struct mdinfo
*dev
,
511 char fname
[MAX_SYSFS_PATH_LEN
];
514 snprintf(fname
, MAX_SYSFS_PATH_LEN
, "/sys/block/%s/md/%s/%s",
515 sra
->sys_name
, dev
?dev
->sys_name
:"", name
);
516 fd
= open(fname
, O_RDWR
);
518 fd
= open(fname
, O_RDONLY
);
522 int sysfs_fd_get_ll(int fd
, unsigned long long *val
)
529 n
= read(fd
, buf
, sizeof(buf
));
530 if (n
<= 0 || n
== sizeof(buf
))
533 *val
= strtoull(buf
, &ep
, 0);
534 if (ep
== buf
|| (*ep
!= 0 && *ep
!= '\n' && *ep
!= ' '))
539 int sysfs_get_ll(struct mdinfo
*sra
, struct mdinfo
*dev
,
540 char *name
, unsigned long long *val
)
545 fd
= sysfs_get_fd(sra
, dev
, name
);
548 n
= sysfs_fd_get_ll(fd
, val
);
553 int sysfs_fd_get_two(int fd
, unsigned long long *v1
, unsigned long long *v2
)
555 /* two numbers in this sysfs file, either
565 n
= read(fd
, buf
, sizeof(buf
));
566 if (n
<= 0 || n
== sizeof(buf
))
569 *v1
= strtoull(buf
, &ep
, 0);
570 if (ep
== buf
|| (*ep
!= 0 && *ep
!= '\n' && *ep
!= ' '))
572 while (*ep
== ' ' || *ep
== '/' || *ep
== '(')
574 *v2
= strtoull(ep
, &ep2
, 0);
575 if (ep2
== ep
|| (*ep2
!= 0 && *ep2
!= '\n' && *ep2
!= ' ' && *ep2
!= ')')) {
582 int sysfs_get_two(struct mdinfo
*sra
, struct mdinfo
*dev
,
583 char *name
, unsigned long long *v1
, unsigned long long *v2
)
588 fd
= sysfs_get_fd(sra
, dev
, name
);
591 n
= sysfs_fd_get_two(fd
, v1
, v2
);
596 int sysfs_fd_get_str(int fd
, char *val
, int size
)
601 n
= read(fd
, val
, size
);
602 if (n
<= 0 || n
== size
)
608 int sysfs_get_str(struct mdinfo
*sra
, struct mdinfo
*dev
,
609 char *name
, char *val
, int size
)
614 fd
= sysfs_get_fd(sra
, dev
, name
);
617 n
= sysfs_fd_get_str(fd
, val
, size
);
622 int sysfs_set_safemode(struct mdinfo
*sra
, unsigned long ms
)
631 sprintf(delay
, "%ld.%03ld\n", sec
, msec
);
632 /* this '\n' ^ needed for kernels older than 2.6.28 */
633 return sysfs_set_str(sra
, NULL
, "safe_mode_delay", delay
);
636 int sysfs_set_array(struct mdinfo
*info
, int vers
)
640 int raid_disks
= info
->array
.raid_disks
;
643 if (info
->array
.major_version
== -1 &&
644 info
->array
.minor_version
== -2) {
647 strcat(strcpy(ver
, "external:"), info
->text_version
);
649 /* meta version might already be set if we are setting
650 * new geometry for a reshape. In that case we don't
651 * want to over-write the 'readonly' flag that is
652 * stored in the metadata version. So read the current
653 * version first, and preserve the flag
655 if (sysfs_get_str(info
, NULL
, "metadata_version",
657 if (strlen(buf
) >= 9 && buf
[9] == '-')
660 if ((vers
% 100) < 2 ||
661 sysfs_set_str(info
, NULL
, "metadata_version",
663 pr_err("This kernel does not support external metadata.\n");
667 if (info
->array
.level
< 0)
668 return 0; /* FIXME */
669 rv
|= sysfs_set_str(info
, NULL
, "level",
670 map_num(pers
, info
->array
.level
));
671 if (info
->reshape_active
&& info
->delta_disks
!= UnSet
)
672 raid_disks
-= info
->delta_disks
;
673 rv
|= sysfs_set_num(info
, NULL
, "raid_disks", raid_disks
);
674 rv
|= sysfs_set_num(info
, NULL
, "chunk_size", info
->array
.chunk_size
);
675 rv
|= sysfs_set_num(info
, NULL
, "layout", info
->array
.layout
);
676 rv
|= sysfs_set_num(info
, NULL
, "component_size", info
->component_size
/2);
677 if (info
->custom_array_size
) {
680 rc
= sysfs_set_num(info
, NULL
, "array_size",
681 info
->custom_array_size
/2);
682 if (rc
&& errno
== ENOENT
) {
683 pr_err("This kernel does not have the md/array_size attribute, the array may be larger than expected\n");
689 if (info
->array
.level
> 0)
690 rv
|= sysfs_set_num(info
, NULL
, "resync_start", info
->resync_start
);
692 if (info
->reshape_active
) {
693 rv
|= sysfs_set_num(info
, NULL
, "reshape_position",
694 info
->reshape_progress
);
695 rv
|= sysfs_set_num(info
, NULL
, "chunk_size", info
->new_chunk
);
696 rv
|= sysfs_set_num(info
, NULL
, "layout", info
->new_layout
);
697 rv
|= sysfs_set_num(info
, NULL
, "raid_disks",
698 info
->array
.raid_disks
);
699 /* We don't set 'new_level' here. That can only happen
700 * once the reshape completes.
704 if (info
->consistency_policy
== CONSISTENCY_POLICY_PPL
) {
705 if (sysfs_set_str(info
, NULL
, "consistency_policy",
706 map_num(consistency_policies
,
707 info
->consistency_policy
))) {
708 pr_err("This kernel does not support PPL\n");
716 int sysfs_add_disk(struct mdinfo
*sra
, struct mdinfo
*sd
, int resume
)
724 sprintf(dv
, "%d:%d", sd
->disk
.major
, sd
->disk
.minor
);
725 rv
= sysfs_set_str(sra
, NULL
, "new_dev", dv
);
729 memset(nm
, 0, sizeof(nm
));
730 dname
= devid2kname(makedev(sd
->disk
.major
, sd
->disk
.minor
));
731 strcpy(sd
->sys_name
, "dev-");
732 strcpy(sd
->sys_name
+4, dname
);
734 /* test write to see if 'recovery_start' is available */
735 if (resume
&& sd
->recovery_start
< MaxSector
&&
736 sysfs_set_num(sra
, sd
, "recovery_start", 0)) {
737 sysfs_set_str(sra
, sd
, "state", "remove");
741 rv
= sysfs_set_num(sra
, sd
, "offset", sd
->data_offset
);
742 rv
|= sysfs_set_num(sra
, sd
, "size", (sd
->component_size
+1) / 2);
743 if (sra
->array
.level
!= LEVEL_CONTAINER
) {
744 if (sd
->consistency_policy
== CONSISTENCY_POLICY_PPL
) {
745 rv
|= sysfs_set_num(sra
, sd
, "ppl_sector", sd
->ppl_sector
);
746 rv
|= sysfs_set_num(sra
, sd
, "ppl_size", sd
->ppl_size
);
748 if (sd
->recovery_start
== MaxSector
)
749 /* This can correctly fail if array isn't started,
750 * yet, so just ignore status for now.
752 sysfs_set_str(sra
, sd
, "state", "insync");
753 if (sd
->disk
.raid_disk
>= 0)
754 rv
|= sysfs_set_num(sra
, sd
, "slot", sd
->disk
.raid_disk
);
756 sysfs_set_num(sra
, sd
, "recovery_start", sd
->recovery_start
);
758 if (sd
->bb
.supported
) {
759 if (sysfs_set_str(sra
, sd
, "state", "external_bbl")) {
761 * backward compatibility - if kernel doesn't support
762 * bad blocks for external metadata, let it continue
763 * as long as there are none known so far
766 pr_err("The kernel has no support for bad blocks in external metadata\n");
771 for (i
= 0; i
< sd
->bb
.count
; i
++) {
773 const struct md_bb_entry
*entry
= &sd
->bb
.entries
[i
];
775 snprintf(s
, sizeof(s
) - 1, "%llu %d\n", entry
->sector
,
777 rv
|= sysfs_set_str(sra
, sd
, "bad_blocks", s
);
784 int sysfs_disk_to_sg(int fd
)
786 /* from an open block device, try find and open its corresponding
787 * scsi_generic interface
792 char sg_major_minor
[10];
796 int major
, minor
, rv
;
801 snprintf(path
, sizeof(path
), "/sys/dev/block/%d:%d/device",
802 major(st
.st_rdev
), minor(st
.st_rdev
));
810 if (strncmp("scsi_generic:", de
->d_name
,
811 strlen("scsi_generic:")) == 0)
820 snprintf(sg_path
, sizeof(sg_path
), "%s/%s/dev", path
, de
->d_name
);
821 fd
= open(sg_path
, O_RDONLY
);
825 rv
= read(fd
, sg_major_minor
, sizeof(sg_major_minor
));
827 if (rv
< 0 || rv
== sizeof(sg_major_minor
))
830 sg_major_minor
[rv
- 1] = '\0';
832 c
= strchr(sg_major_minor
, ':');
835 major
= strtol(sg_major_minor
, NULL
, 10);
836 minor
= strtol(c
, NULL
, 10);
837 snprintf(path
, sizeof(path
), "/dev/.tmp.md.%d:%d:%d",
838 (int) getpid(), major
, minor
);
839 if (mknod(path
, S_IFCHR
|0600, makedev(major
, minor
))==0) {
840 fd
= open(path
, O_RDONLY
);
849 int sysfs_disk_to_scsi_id(int fd
, __u32
*id
)
851 /* from an open block device, try to retrieve it scsi_id */
856 int host
, bus
, target
, lun
;
861 snprintf(path
, sizeof(path
), "/sys/dev/block/%d:%d/device/scsi_device",
862 major(st
.st_rdev
), minor(st
.st_rdev
));
868 for (de
= readdir(dir
); de
; de
= readdir(dir
)) {
871 if (de
->d_type
!= DT_DIR
)
874 count
= sscanf(de
->d_name
, "%d:%d:%d:%d", &host
, &bus
, &target
, &lun
);
883 *id
= (host
<< 24) | (bus
<< 16) | (target
<< 8) | (lun
<< 0);
887 int sysfs_unique_holder(char *devnm
, long rdev
)
889 /* Check that devnm is a holder of rdev,
890 * and is the only holder.
891 * we should be locked against races by
894 * 0 - not unique, not even a holder
895 * 1 - unique, this is the only holder.
896 * 2/3 - not unique, there is another holder
897 * -1 - error, cannot find the holders
904 sprintf(dirname
, "/sys/dev/block/%d:%d/holders",
905 major(rdev
), minor(rdev
));
906 dir
= opendir(dirname
);
910 while ((de
= readdir(dir
)) != NULL
) {
917 if (de
->d_name
[0] == '.')
919 strcpy(dirname
+l
, "/");
920 strcat(dirname
+l
, de
->d_name
);
921 n
= readlink(dirname
, buf
, sizeof(buf
)-1);
925 sl
= strrchr(buf
, '/');
930 if (strcmp(devnm
, sl
) == 0)
939 int sysfs_freeze_array(struct mdinfo
*sra
)
941 /* Try to freeze resync/rebuild on this array/container.
942 * Return -1 if the array is busy,
943 * return 0 if this kernel doesn't support 'frozen'
944 * return 1 if it worked.
948 if (!sysfs_attribute_available(sra
, NULL
, "sync_action"))
949 return 1; /* no sync_action == frozen */
950 if (sysfs_get_str(sra
, NULL
, "sync_action", buf
, 20) <= 0)
952 if (strcmp(buf
, "frozen\n") == 0)
955 if (strcmp(buf
, "idle\n") != 0 && strcmp(buf
, "recover\n") != 0)
957 if (sysfs_set_str(sra
, NULL
, "sync_action", "frozen") < 0)
962 int sysfs_wait(int fd
, int *msec
)
964 /* Wait up to '*msec' for fd to have an exception condition.
965 * if msec == NULL, wait indefinitely.
972 n
= select(fd
+1, NULL
, NULL
, &fds
, NULL
);
976 struct timeval start
, end
, tv
;
977 gettimeofday(&start
, NULL
);
980 tv
.tv_usec
= (*msec
)*1000;
982 tv
.tv_sec
= (*msec
)/1000;
985 n
= select(fd
+1, NULL
, NULL
, &fds
, &tv
);
986 gettimeofday(&end
, NULL
);
987 end
.tv_sec
-= start
.tv_sec
;
988 *msec
-= (end
.tv_sec
* 1000 + end
.tv_usec
/1000
989 - start
.tv_usec
/1000) + 1;