2 * mdadm - manage Linux "md" devices aka RAID arrays.
4 * Copyright (C) 2011 Neil Brown <neilb@suse.de>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * Email: <neilb@suse.de>
29 /* This fill contains various 'library' style function. They
30 * have no dependency on anything outside this file.
33 int get_mdp_major(void)
35 static int mdp_major = -1;
45 fl = fopen("/proc/devices", "r");
49 while ((w = conf_word(fl, 1))) {
50 if (have_block && strcmp(w, "devices:") == 0)
52 have_block = (strcmp(w, "Block") == 0);
55 if (have_devices && strcmp(w, "mdp") == 0)
64 char *devid2kname(int devid)
68 static char devnm[32];
73 * /sys/dev/block/%d:%d link which must look like
74 * and take the last component.
76 sprintf(path, "/sys/dev/block/%d:%d", major(devid),
78 n = readlink(path, link, sizeof(link) - 1);
81 cp = strrchr(link, '/');
83 strcpy(devnm, cp + 1);
90 char *stat2kname(struct stat *st)
92 if ((S_IFMT & st->st_mode) != S_IFBLK)
95 return devid2kname(st->st_rdev);
98 char *fd2kname(int fd)
102 if (fstat(fd, &stb) == 0)
103 return stat2kname(&stb);
108 char *devid2devnm(dev_t devid)
112 static char devnm[32];
116 /* Might be an extended-minor partition or a
117 * named md device. Look at the
118 * /sys/dev/block/%d:%d link which must look like
119 * ../../block/mdXXX/mdXXXpYY
123 sprintf(path, "/sys/dev/block/%d:%d", major(devid), minor(devid));
124 n = readlink(path, link, sizeof(link) - 1);
127 cp = strstr(link, "/block/");
130 ep = strchr(cp, '/');
137 if (major(devid) == MD_MAJOR)
138 sprintf(devnm,"md%d", minor(devid));
139 else if (major(devid) == (unsigned)get_mdp_major())
140 sprintf(devnm,"md_d%d",
141 (minor(devid)>>MdpMinorShift));
148 char *stat2devnm(struct stat *st)
150 if ((S_IFMT & st->st_mode) != S_IFBLK)
153 return devid2devnm(st->st_rdev);
156 char *fd2devnm(int fd)
160 if (fstat(fd, &stb) == 0)
161 return stat2devnm(&stb);
167 * convert a major/minor pair for a block device into a name in /dev, if possible.
168 * On the first call, walk /dev collecting name.
169 * Put them in a simple linked listfor now.
176 int devlist_ready = 0;
178 int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s)
182 if (S_ISLNK(stb->st_mode)) {
183 if (stat(name, &st) != 0)
188 if ((stb->st_mode&S_IFMT)== S_IFBLK) {
189 char *n = xstrdup(name);
190 struct devmap *dm = xmalloc(sizeof(*dm));
191 if (strncmp(n, "/dev/./", 7) == 0)
192 strcpy(n + 4, name + 6);
194 dm->major = major(stb->st_rdev);
195 dm->minor = minor(stb->st_rdev);
207 int add_dev_1(const char *name, const struct stat *stb, int flag)
209 return add_dev(name, stb, flag, NULL);
211 int nftw(const char *path,
212 int (*han)(const char *name, const struct stat *stb,
213 int flag, struct FTW *s), int nopenfd, int flags)
215 return ftw(path, add_dev_1, nopenfd);
218 int nftw(const char *path,
219 int (*han)(const char *name, const struct stat *stb,
220 int flag, struct FTW *s), int nopenfd, int flags)
224 #endif /* HAVE_FTW */
225 #endif /* HAVE_NFTW */
228 * Find a block device with the right major/minor number.
229 * If we find multiple names, choose the shortest.
230 * If we find a name in /dev/md/, we prefer that.
231 * This applies only to names for MD devices.
232 * If 'prefer' is set (normally to e.g. /by-path/)
233 * then we prefer a name which contains that string.
235 char *map_dev_preferred(int major, int minor, int create,
239 char *regular = NULL, *preferred=NULL;
242 if (major == 0 && minor == 0)
246 if (!devlist_ready) {
250 struct devmap *d = devlist;
255 if (lstat(dev, &stb) == 0 && S_ISLNK(stb.st_mode))
257 nftw(dev, add_dev, 10, FTW_PHYS);
262 for (p = devlist; p; p = p->next)
263 if (p->major == major && p->minor == minor) {
264 if (strncmp(p->name, "/dev/md/",8) == 0 ||
265 (prefer && strstr(p->name, prefer))) {
266 if (preferred == NULL ||
267 strlen(p->name) < strlen(preferred))
270 if (regular == NULL ||
271 strlen(p->name) < strlen(regular))
275 if (!regular && !preferred && !did_check) {
279 if (create && !regular && !preferred) {
281 snprintf(buf, sizeof(buf), "%d:%d", major, minor);
285 return preferred ? preferred : regular;
288 /* conf_word gets one word from the conf file.
289 * if "allow_key", then accept words at the start of a line,
290 * otherwise stop when such a word is found.
291 * We assume that the file pointer is at the end of a word, so the
292 * next character is a space, or a newline. If not, it is the start of a line.
295 char *conf_word(FILE *file, int allow_key)
302 char *word = xmalloc(wsize);
304 while (wordfound == 0) {
305 /* at the end of a word.. */
308 while (c != EOF && c != '\n')
315 if (c != ' ' && c != '\t' && ! allow_key) {
319 /* looks like it is safe to get a word here, if there is one */
321 /* first, skip any spaces */
322 while (c == ' ' || c == '\t')
324 if (c != EOF && c != '\n' && c != '#') {
325 /* we really have a character of a word, so start saving it */
326 while (c != EOF && c != '\n' &&
327 (quote || (c != ' ' && c != '\t'))) {
329 if (quote && c == quote)
331 else if (quote == 0 && (c == '\'' || c == '"'))
334 if (len == wsize-1) {
336 word = xrealloc(word, wsize);
341 /* Hack for broken kernels (2.6.14-.24) that put
342 * "active(auto-read-only)"
343 * in /proc/mdstat instead of
344 * "active (auto-read-only)"
346 if (c == '(' && len >= 6 &&
347 strncmp(word + len - 6, "active", 6) == 0)
356 /* Further HACK for broken kernels.. 2.6.14-2.6.24 */
357 if (strcmp(word, "auto-read-only)") == 0)
358 strcpy(word, "(auto-read-only)");
360 /* printf("word is <%s>\n", word); */
368 void print_quoted(char *str)
370 /* Printf the string with surrounding quotes
372 * If no space, tab, or quote - leave unchanged.
373 * Else print surrounded by " or ', swapping quotes
374 * when we find one that will cause confusion.
377 char first_quote = 0, q;
380 for (c = str; *c; c++) {
400 if (first_quote == '"')
405 for (c = str; *c; c++) {
416 void print_escape(char *str)
418 /* print str, but change space and tab to '_'
419 * as is suitable for device names
421 for (; *str; str++) {
436 int check_env(char *name)
438 char *val = getenv(name);
440 if (val && atoi(val) == 1)
452 use = ((stat("/dev/.udev", &stb) == 0 ||
453 stat("/run/udev", &stb) == 0) &&
454 check_env("MDADM_NO_UDEV") == 0);
459 unsigned long GCD(unsigned long a, unsigned long b)
471 * conf_line reads one logical line from the conffile or mdstat.
472 * It skips comments and continues until it finds a line that starts
473 * with a non blank/comment. This character is pushed back for the next call
474 * A doubly linked list of words is returned.
475 * the first word will be a keyword. Other words will have had quotes removed.
478 char *conf_line(FILE *file)
483 w = conf_word(file, 1);
491 while ((w = conf_word(file, 0))){
492 char *w2 = dl_strdup(w);
496 /* printf("got a line\n");*/
500 void free_line(char *line)
503 for (w = dl_next(line); w != line; w = dl_next(line)) {