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Diffstat (limited to 'mdstat.c')
-rw-r--r-- | mdstat.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/mdstat.c b/mdstat.c new file mode 100644 index 0000000..2fd792c --- /dev/null +++ b/mdstat.c @@ -0,0 +1,441 @@ +/* + * mdstat - parse /proc/mdstat file. Part of: + * mdadm - manage Linux "md" devices aka RAID arrays. + * + * Copyright (C) 2002-2009 Neil Brown <neilb@suse.de> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Author: Neil Brown + * Email: <neilb@suse.de> + */ + +/* + * The /proc/mdstat file comes in at least 3 flavours: + * In an unpatched 2.2 kernel (md 0.36.6): + * Personalities : [n raidx] ... + * read_ahead {not set|%d sectors} + * md0 : {in}active{ raidX /dev/hda... %d blocks{ maxfault=%d}} + * md1 : ..... + * + * Normally only 4 md lines, but all are listed. + * + * In a patched 2.2 kernel (md 0.90.0) + * Personalities : [raidx] ... + * read_ahead {not set|%d sectors} + * mdN : {in}active {(readonly)} raidX dev[%d]{(F)} ... %d blocks STATUS RESYNC + * ... Only initialised arrays listed + * unused devices: {dev dev ... | <none>} + * + * STATUS is personality dependant: + * linear: %dk rounding + * raid0: %dk chunks + * raid1: [%d/%d] [U_U] ( raid/working. operational or not) + * raid5: level 4/5, %dk chunk, algorithm %d [%d/%d] [U_U] + * + * RESYNC is empty or: + * {resync|recovery}=%u%% finish=%u.%umin + * or + * resync=DELAYED + * + * In a 2.4 kernel (md 0.90.0/2.4) + * Personalities : [raidX] ... + * read_ahead {not set|%d sectors} + * mdN : {in}active {(read-only)} raidX dev[%d]{(F)} ... + * %d blocks STATUS + * RESYNC + * unused devices: {dev dev .. | <none>} + * + * STATUS matches 0.90.0/2.2 + * RESYNC includes [===>....], + * adds a space after {resync|recovery} and before and after '=' + * adds a decimal to the recovery percent. + * adds (%d/%d) resync amount and max_blocks, before finish. + * adds speed=%dK/sec after finish + * + * + * + * Out of this we want to extract: + * list of devices, active or not + * pattern of failed drives (so need number of drives) + * percent resync complete + * + * As continuation is indicated by leading space, we use + * conf_line from config.c to read logical lines + * + */ + +#include "mdadm.h" +#include "dlink.h" +#include <sys/select.h> +#include <ctype.h> + +static void free_member_devnames(struct dev_member *m) +{ + while(m) { + struct dev_member *t = m; + + m = m->next; + free(t->name); + free(t); + } +} + +static int add_member_devname(struct dev_member **m, char *name) +{ + struct dev_member *new; + char *t; + + if ((t = strchr(name, '[')) == NULL) + /* not a device */ + return 0; + + new = xmalloc(sizeof(*new)); + new->name = strndup(name, t - name); + new->next = *m; + *m = new; + return 1; +} + +void free_mdstat(struct mdstat_ent *ms) +{ + while (ms) { + struct mdstat_ent *t; + free(ms->level); + free(ms->pattern); + free(ms->metadata_version); + free_member_devnames(ms->members); + t = ms; + ms = ms->next; + free(t); + } +} + +static int mdstat_fd = -1; +struct mdstat_ent *mdstat_read(int hold, int start) +{ + FILE *f; + struct mdstat_ent *all, *rv, **end, **insert_here; + char *line; + int fd; + + if (hold && mdstat_fd != -1) { + off_t offset = lseek(mdstat_fd, 0L, 0); + if (offset == (off_t)-1) { + return NULL; + } + fd = dup(mdstat_fd); + if (fd >= 0) + f = fdopen(fd, "r"); + else + return NULL; + } else + f = fopen("/proc/mdstat", "r"); + if (f == NULL) + return NULL; + else + fcntl(fileno(f), F_SETFD, FD_CLOEXEC); + + all = NULL; + end = &all; + for (; (line = conf_line(f)) ; free_line(line)) { + struct mdstat_ent *ent; + char *w; + char devnm[32]; + int in_devs = 0; + + if (strcmp(line, "Personalities") == 0) + continue; + if (strcmp(line, "read_ahead") == 0) + continue; + if (strcmp(line, "unused") == 0) + continue; + insert_here = NULL; + /* Better be an md line.. */ + if (strncmp(line, "md", 2)!= 0 || strlen(line) >= 32 || + (line[2] != '_' && !isdigit(line[2]))) + continue; + strcpy(devnm, line); + + ent = xmalloc(sizeof(*ent)); + ent->level = ent->pattern= NULL; + ent->next = NULL; + ent->percent = RESYNC_NONE; + ent->active = -1; + ent->resync = 0; + ent->metadata_version = NULL; + ent->raid_disks = 0; + ent->devcnt = 0; + ent->members = NULL; + + strcpy(ent->devnm, devnm); + + for (w=dl_next(line); w!= line ; w=dl_next(w)) { + int l = strlen(w); + char *eq; + if (strcmp(w, "active") == 0) + ent->active = 1; + else if (strcmp(w, "inactive") == 0) { + ent->active = 0; + in_devs = 1; + } else if (strcmp(w, "bitmap:") == 0) { + /* We need to stop parsing here; + * otherwise, ent->raid_disks will be + * overwritten by the wrong value. + */ + break; + } else if (ent->active > 0 && + ent->level == NULL && + w[0] != '(' /*readonly*/) { + ent->level = xstrdup(w); + in_devs = 1; + } else if (in_devs && strcmp(w, "blocks") == 0) + in_devs = 0; + else if (in_devs) { + char *ep = strchr(w, '['); + ent->devcnt += + add_member_devname(&ent->members, w); + if (ep && strncmp(w, "md", 2) == 0) { + /* This has an md device as a component. + * If that device is already in the + * list, make sure we insert before + * there. + */ + struct mdstat_ent **ih; + ih = &all; + while (ih != insert_here && *ih && + ((int)strlen((*ih)->devnm) != + ep-w || + strncmp((*ih)->devnm, w, + ep-w) != 0)) + ih = & (*ih)->next; + insert_here = ih; + } + } else if (strcmp(w, "super") == 0 && + dl_next(w) != line) { + w = dl_next(w); + ent->metadata_version = xstrdup(w); + } else if (w[0] == '[' && isdigit(w[1])) { + ent->raid_disks = atoi(w+1); + } else if (!ent->pattern && + w[0] == '[' && + (w[1] == 'U' || w[1] == '_')) { + ent->pattern = xstrdup(w+1); + if (ent->pattern[l-2] == ']') + ent->pattern[l-2] = '\0'; + } else if (ent->percent == RESYNC_NONE && + strncmp(w, "re", 2) == 0 && + w[l-1] == '%' && + (eq = strchr(w, '=')) != NULL ) { + ent->percent = atoi(eq+1); + if (strncmp(w,"resync", 6) == 0) + ent->resync = 1; + else if (strncmp(w, "reshape", 7) == 0) + ent->resync = 2; + else + ent->resync = 0; + } else if (ent->percent == RESYNC_NONE && + (w[0] == 'r' || w[0] == 'c')) { + if (strncmp(w, "resync", 6) == 0) + ent->resync = 1; + if (strncmp(w, "reshape", 7) == 0) + ent->resync = 2; + if (strncmp(w, "recovery", 8) == 0) + ent->resync = 0; + if (strncmp(w, "check", 5) == 0) + ent->resync = 3; + + if (l > 8 && strcmp(w+l-8, "=DELAYED") == 0) + ent->percent = RESYNC_DELAYED; + if (l > 8 && strcmp(w+l-8, "=PENDING") == 0) + ent->percent = RESYNC_PENDING; + if (l > 7 && strcmp(w+l-7, "=REMOTE") == 0) + ent->percent = RESYNC_REMOTE; + } else if (ent->percent == RESYNC_NONE && + w[0] >= '0' && + w[0] <= '9' && + w[l-1] == '%') { + ent->percent = atoi(w); + } + } + if (insert_here && (*insert_here)) { + ent->next = *insert_here; + *insert_here = ent; + } else { + *end = ent; + end = &ent->next; + } + } + if (hold && mdstat_fd == -1) { + mdstat_fd = dup(fileno(f)); + fcntl(mdstat_fd, F_SETFD, FD_CLOEXEC); + } + fclose(f); + + /* If we might want to start array, + * reverse the order, so that components comes before composites + */ + if (start) { + rv = NULL; + while (all) { + struct mdstat_ent *e = all; + all = all->next; + e->next = rv; + rv = e; + } + } else + rv = all; + return rv; +} + +void mdstat_close(void) +{ + if (mdstat_fd >= 0) + close(mdstat_fd); + mdstat_fd = -1; +} + +/* + * function: mdstat_wait + * Description: Function waits for event on mdstat. + * Parameters: + * seconds - timeout for waiting + * Returns: + * > 0 - detected event + * 0 - timeout + * < 0 - detected error + */ +int mdstat_wait(int seconds) +{ + fd_set fds; + struct timeval tm; + int maxfd = 0; + FD_ZERO(&fds); + if (mdstat_fd >= 0) { + FD_SET(mdstat_fd, &fds); + maxfd = mdstat_fd; + } else + return -1; + + tm.tv_sec = seconds; + tm.tv_usec = 0; + + return select(maxfd + 1, NULL, NULL, &fds, &tm); +} + +void mdstat_wait_fd(int fd, const sigset_t *sigmask) +{ + fd_set fds, rfds; + int maxfd = 0; + + FD_ZERO(&fds); + FD_ZERO(&rfds); + if (mdstat_fd >= 0) + FD_SET(mdstat_fd, &fds); + + if (fd >= 0) { + struct stat stb; + fstat(fd, &stb); + if ((stb.st_mode & S_IFMT) == S_IFREG) + /* Must be a /proc or /sys fd, so expect + * POLLPRI + * i.e. an 'exceptional' event. + */ + FD_SET(fd, &fds); + else + FD_SET(fd, &rfds); + + if (fd > maxfd) + maxfd = fd; + + } + if (mdstat_fd > maxfd) + maxfd = mdstat_fd; + + pselect(maxfd + 1, &rfds, NULL, &fds, + NULL, sigmask); +} + +int mddev_busy(char *devnm) +{ + struct mdstat_ent *mdstat = mdstat_read(0, 0); + struct mdstat_ent *me; + + for (me = mdstat ; me ; me = me->next) + if (strcmp(me->devnm, devnm) == 0) + break; + free_mdstat(mdstat); + return me != NULL; +} + +struct mdstat_ent *mdstat_by_component(char *name) +{ + struct mdstat_ent *mdstat = mdstat_read(0, 0); + + while (mdstat) { + struct dev_member *m; + struct mdstat_ent *ent; + if (mdstat->metadata_version && + strncmp(mdstat->metadata_version, "external:", 9) == 0 && + is_subarray(mdstat->metadata_version+9)) + /* don't return subarrays, only containers */ + ; + else for (m = mdstat->members; m; m = m->next) { + if (strcmp(m->name, name) == 0) { + free_mdstat(mdstat->next); + mdstat->next = NULL; + return mdstat; + } + } + ent = mdstat; + mdstat = mdstat->next; + ent->next = NULL; + free_mdstat(ent); + } + return NULL; +} + +struct mdstat_ent *mdstat_by_subdev(char *subdev, char *container) +{ + struct mdstat_ent *mdstat = mdstat_read(0, 0); + struct mdstat_ent *ent = NULL; + + while (mdstat) { + /* metadata version must match: + * external:[/-]%s/%s + * where first %s is 'container' and second %s is 'subdev' + */ + if (ent) + free_mdstat(ent); + ent = mdstat; + mdstat = mdstat->next; + ent->next = NULL; + + if (ent->metadata_version == NULL || + strncmp(ent->metadata_version, "external:", 9) != 0) + continue; + + if (!metadata_container_matches(ent->metadata_version+9, + container) || + !metadata_subdev_matches(ent->metadata_version+9, + subdev)) + continue; + + free_mdstat(mdstat); + return ent; + } + return NULL; +} |