]> git.ipfire.org Git - thirdparty/mdadm.git/blobdiff - mapfile.c
mdadm: load default sysfs attributes after assemblation
[thirdparty/mdadm.git] / mapfile.c
index 366ebe332299c92fceaa4d3c9fa2e8c644b27801..8d7acb3cc389ca0ce49c1dabb99bfe2782875993 100644 (file)
--- a/mapfile.c
+++ b/mapfile.c
@@ -1,8 +1,8 @@
 /*
- * mapfile - manage /var/run/mdadm.map. Part of:
+ * mapfile - keep track of uuid <-> array mapping. Part of:
  * mdadm - manage Linux "md" devices aka RAID arrays.
  *
- * Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
+ * Copyright (C) 2006-2010 Neil Brown <neilb@suse.de>
  *
  *
  *    This program is free software; you can redistribute it and/or modify
@@ -28,8 +28,8 @@
  *           Australia
  */
 
-/* /var/run/mdadm.map is used to track arrays being created in --incremental
- * more.  It particularly allows lookup from UUID to array device, but
+/* The mapfile is used to track arrays being created in --incremental
+ * mode.  It particularly allows lookup from UUID to array device, but
  * also allows the array device name to be easily found.
  *
  * The map file is line based with space separated fields.  The fields are:
  *  UUID       -  uuid of the array
  *  path       -  path where device created: /dev/md/home
  *
- * The preferred location for the map file is /var/run/mdadm.map.
- * However /var/run may not exist or be writable in early boot.  And if
- * no-one has created /var/run/mdadm, we still want to survive.
- * So possible locations are:
- *   /var/run/mdadm/map  /var/run/mdadm.map  /dev/.mdadm.map
- * the last, because udev requires a writable /dev very early.
- * We read from the first one that exists and write to the first
- * one that we can.
+ * The best place for the mapfile is /run/mdadm/map.  Distros and users
+ * which have not switched to /run yet can choose a different location
+ * at compile time via MAP_DIR and MAP_FILE.
  */
 #include       "mdadm.h"
 #include       <sys/file.h>
 #include       <ctype.h>
 
-#define mapnames(base) { base, base ".new", base ".lock"}
-char *mapname[3][3] = {
-       mapnames(VAR_RUN "/map"),
-       mapnames("/var/run/mdadm.map"),
-       mapnames(ALT_RUN "/map")
+#define MAP_READ 0
+#define MAP_NEW 1
+#define MAP_LOCK 2
+#define MAP_DIRNAME 3
+
+char *mapname[4] = {
+       MAP_DIR "/" MAP_FILE,
+       MAP_DIR "/" MAP_FILE ".new",
+       MAP_DIR "/" MAP_FILE ".lock",
+       MAP_DIR
 };
 
-int mapmode[3] = { O_RDONLY, O_RDWR|O_CREAT, O_RDWR|O_CREAT | O_TRUNC };
+int mapmode[3] = { O_RDONLY, O_RDWR|O_CREAT, O_RDWR|O_CREAT|O_TRUNC };
 char *mapsmode[3] = { "r", "w", "w"};
 
-FILE *open_map(int modenum, int *choice)
+FILE *open_map(int modenum)
 {
-       int i;
-       for (i = 0 ; i < 3 ; i++) {
-               int fd = open(mapname[i][modenum], mapmode[modenum], 0600);
-               if (fd >= 0) {
-                       *choice = i;
-                       return fdopen(fd, mapsmode[modenum]);
-               }
-       }
+       int fd;
+       if ((mapmode[modenum] & O_CREAT))
+               /* Attempt to create directory, don't worry about
+                * failure.
+                */
+               (void)mkdir(mapname[MAP_DIRNAME], 0755);
+       fd = open(mapname[modenum], mapmode[modenum], 0600);
+       if (fd >= 0)
+               return fdopen(fd, mapsmode[modenum]);
        return NULL;
 }
 
@@ -78,19 +79,15 @@ int map_write(struct map_ent *mel)
 {
        FILE *f;
        int err;
-       int which;
 
-       f = open_map(1, &which);
+       f = open_map(MAP_NEW);
 
        if (!f)
                return 0;
        for (; mel; mel = mel->next) {
                if (mel->bad)
                        continue;
-               if (mel->devnum < 0)
-                       fprintf(f, "mdp%d ", -1-mel->devnum);
-               else
-                       fprintf(f, "md%d ", mel->devnum);
+               fprintf(f, "%s ", mel->devnm);
                fprintf(f, "%s ", mel->metadata);
                fprintf(f, "%08x:%08x:%08x:%08x ", mel->uuid[0],
                        mel->uuid[1], mel->uuid[2], mel->uuid[3]);
@@ -100,20 +97,19 @@ int map_write(struct map_ent *mel)
        err = ferror(f);
        fclose(f);
        if (err) {
-               unlink(mapname[which][1]);
+               unlink(mapname[1]);
                return 0;
        }
-       return rename(mapname[which][1],
-                     mapname[which][0]) == 0;
+       return rename(mapname[1],
+                     mapname[0]) == 0;
 }
 
-
 static FILE *lf = NULL;
-static int lwhich = 0;
 int map_lock(struct map_ent **melp)
 {
-       if (lf == NULL) {
-               lf = open_map(2, &lwhich);
+       while (lf == NULL) {
+               struct stat buf;
+               lf = open_map(MAP_LOCK);
                if (lf == NULL)
                        return -1;
                if (flock(fileno(lf), LOCK_EX) != 0) {
@@ -121,6 +117,15 @@ int map_lock(struct map_ent **melp)
                        lf = NULL;
                        return -1;
                }
+               if (fstat(fileno(lf), &buf) != 0 ||
+                   buf.st_nlink == 0) {
+                       /* The owner of the lock unlinked it,
+                        * so we have a lock on a stale file,
+                        * try again
+                        */
+                       fclose(lf);
+                       lf = NULL;
+               }
        }
        if (*melp)
                map_free(*melp);
@@ -131,22 +136,39 @@ int map_lock(struct map_ent **melp)
 void map_unlock(struct map_ent **melp)
 {
        if (lf) {
-               flock(fileno(lf), LOCK_UN);
+               /* must unlink before closing the file,
+                * as only the owner of the lock may
+                * unlink the file
+                */
+               unlink(mapname[2]);
                fclose(lf);
        }
-       unlink(mapname[lwhich][2]);
+       if (*melp)
+               map_free(*melp);
        lf = NULL;
 }
 
+void map_fork(void)
+{
+       /* We are forking, so must close the lock file.
+        * Don't risk flushing anything though.
+        */
+       if (lf) {
+               close(fileno(lf));
+               fclose(lf);
+               lf = NULL;
+       }
+}
+
 void map_add(struct map_ent **melp,
-           int devnum, char *metadata, int uuid[4], char *path)
+            char * devnm, char *metadata, int uuid[4], char *path)
 {
-       struct map_ent *me = malloc(sizeof(*me));
+       struct map_ent *me = xmalloc(sizeof(*me));
 
-       me->devnum = devnum;
+       strcpy(me->devnm, devnm);
        strcpy(me->metadata, metadata);
        memcpy(me->uuid, uuid, 16);
-       me->path = path ? strdup(path) : NULL;
+       me->path = path ? xstrdup(path) : NULL;
        me->next = *melp;
        me->bad = 0;
        *melp = me;
@@ -156,32 +178,27 @@ void map_read(struct map_ent **melp)
 {
        FILE *f;
        char buf[8192];
-       char path[200];
-       int devnum, uuid[4];
+       char path[201];
+       int uuid[4];
+       char devnm[32];
        char metadata[30];
-       char nam[4];
-       int which;
 
        *melp = NULL;
 
-       f = open_map(0, &which);
+       f = open_map(MAP_READ);
        if (!f) {
                RebuildMap();
-               f = open_map(0, &which);
+               f = open_map(MAP_READ);
        }
        if (!f)
                return;
 
        while (fgets(buf, sizeof(buf), f)) {
                path[0] = 0;
-               if (sscanf(buf, " %3[mdp]%d %s %x:%x:%x:%x %200s",
-                          nam, &devnum, metadata, uuid, uuid+1,
+               if (sscanf(buf, " %s %s %x:%x:%x:%x %200s",
+                          devnm, metadata, uuid, uuid+1,
                           uuid+2, uuid+3, path) >= 7) {
-                       if (strncmp(nam, "md", 2) != 0)
-                               continue;
-                       if (nam[2] == 'p')
-                               devnum = -1 - devnum;
-                       map_add(melp, devnum, metadata, uuid, path);
+                       map_add(melp, devnm, metadata, uuid, path);
                }
        }
        fclose(f);
@@ -197,7 +214,7 @@ void map_free(struct map_ent *map)
        }
 }
 
-int map_update(struct map_ent **mpp, int devnum, char *metadata,
+int map_update(struct map_ent **mpp, char *devnm, char *metadata,
               int *uuid, char *path)
 {
        struct map_ent *map, *mp;
@@ -209,15 +226,16 @@ int map_update(struct map_ent **mpp, int devnum, char *metadata,
                map_read(&map);
 
        for (mp = map ; mp ; mp=mp->next)
-               if (mp->devnum == devnum) {
+               if (strcmp(mp->devnm, devnm) == 0) {
                        strcpy(mp->metadata, metadata);
                        memcpy(mp->uuid, uuid, 16);
                        free(mp->path);
-                       mp->path = path ? strdup(path) : NULL;
+                       mp->path = path ? xstrdup(path) : NULL;
+                       mp->bad = 0;
                        break;
                }
        if (!mp)
-               map_add(&map, devnum, metadata, uuid, path);
+               map_add(&map, devnm, metadata, uuid, path);
        if (mpp)
                *mpp = NULL;
        rv = map_write(map);
@@ -225,7 +243,7 @@ int map_update(struct map_ent **mpp, int devnum, char *metadata,
        return rv;
 }
 
-void map_delete(struct map_ent **mapp, int devnum)
+void map_delete(struct map_ent **mapp, char *devnm)
 {
        struct map_ent *mp;
 
@@ -233,7 +251,7 @@ void map_delete(struct map_ent **mapp, int devnum)
                map_read(mapp);
 
        for (mp = *mapp; mp; mp = *mapp) {
-               if (mp->devnum == devnum) {
+               if (strcmp(mp->devnm, devnm) == 0) {
                        *mapp = mp->next;
                        free(mp->path);
                        free(mp);
@@ -242,6 +260,17 @@ void map_delete(struct map_ent **mapp, int devnum)
        }
 }
 
+void map_remove(struct map_ent **mapp, char *devnm)
+{
+       if (devnm[0] == 0)
+               return;
+
+       map_delete(mapp, devnm);
+       map_write(*mapp);
+       map_free(*mapp);
+       *mapp = NULL;
+}
+
 struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
 {
        struct map_ent *mp;
@@ -251,7 +280,7 @@ struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
        for (mp = *map ; mp ; mp = mp->next) {
                if (memcmp(uuid, mp->uuid, 16) != 0)
                        continue;
-               if (!mddev_busy(mp->devnum)) {
+               if (!mddev_busy(mp->devnm)) {
                        mp->bad = 1;
                        continue;
                }
@@ -260,16 +289,16 @@ struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
        return NULL;
 }
 
-struct map_ent *map_by_devnum(struct map_ent **map, int devnum)
+struct map_ent *map_by_devnm(struct map_ent **map, char *devnm)
 {
        struct map_ent *mp;
        if (!*map)
                map_read(map);
 
        for (mp = *map ; mp ; mp = mp->next) {
-               if (mp->devnum != devnum)
+               if (strcmp(mp->devnm, devnm) != 0)
                        continue;
-               if (!mddev_busy(mp->devnum)) {
+               if (!mddev_busy(mp->devnm)) {
                        mp->bad = 1;
                        continue;
                }
@@ -291,7 +320,7 @@ struct map_ent *map_by_name(struct map_ent **map, char *name)
                        continue;
                if (strcmp(mp->path+8, name) != 0)
                        continue;
-               if (!mddev_busy(mp->devnum)) {
+               if (!mddev_busy(mp->devnm)) {
                        mp->bad = 1;
                        continue;
                }
@@ -304,31 +333,20 @@ struct map_ent *map_by_name(struct map_ent **map, char *name)
  * version super_by_fd does this automatically, this routine is meant as
  * a supplement for guess_super()
  */
-static void set_member_info(struct supertype *st, struct mdstat_ent *ent)
+static char *get_member_info(struct mdstat_ent *ent)
 {
 
-       st->subarray[0] = '\0';
-
        if (ent->metadata_version == NULL ||
            strncmp(ent->metadata_version, "external:", 9) != 0)
-               return;
+               return NULL;
 
        if (is_subarray(&ent->metadata_version[9])) {
-               char version[strlen(ent->metadata_version)+1];
                char *subarray;
-               char *name = &version[10];
 
-               strcpy(version, ent->metadata_version);
-               subarray = strrchr(version, '/');
-               name = &version[10];
-
-               if (!subarray)
-                       return;
-               *subarray++ = '\0';
-
-               st->container_dev = devname2devnum(name);
-               strncpy(st->subarray, subarray, sizeof(st->subarray));
+               subarray = strrchr(ent->metadata_version, '/');
+               return subarray + 1;
        }
+       return NULL;
 }
 
 void RebuildMap(void)
@@ -336,7 +354,6 @@ void RebuildMap(void)
        struct mdstat_ent *mdstat = mdstat_read(0, 0);
        struct mdstat_ent *md;
        struct map_ent *map = NULL;
-       int mdp = get_mdp_major();
        int require_homehost;
        char sys_hostname[256];
        char *homehost = conf_get_homehost(&require_homehost);
@@ -349,7 +366,7 @@ void RebuildMap(void)
        }
 
        for (md = mdstat ; md ; md = md->next) {
-               struct mdinfo *sra = sysfs_read(-1, md->devnum, GET_DEVS|SKIP_GONE_DEVS);
+               struct mdinfo *sra = sysfs_read(-1, md->devnm, GET_DEVS);
                struct mdinfo *sd;
 
                if (!sra)
@@ -360,9 +377,11 @@ void RebuildMap(void)
                        char dn[30];
                        int dfd;
                        int ok;
+                       dev_t devid;
                        struct supertype *st;
+                       char *subarray = NULL;
                        char *path;
-                       struct mdinfo info;
+                       struct mdinfo *info;
 
                        sprintf(dn, "%d:%d", sd->disk.major, sd->disk.minor);
                        dfd = dev_open(dn, O_RDONLY);
@@ -372,33 +391,41 @@ void RebuildMap(void)
                        if ( st == NULL)
                                ok = -1;
                        else {
-                               set_member_info(st, md);
+                               subarray = get_member_info(md);
                                ok = st->ss->load_super(st, dfd, NULL);
                        }
                        close(dfd);
                        if (ok != 0)
                                continue;
-                       st->ss->getinfo_super(st, &info);
-                       if (md->devnum >= 0)
-                               path = map_dev(MD_MAJOR, md->devnum, 0);
-                       else
-                               path = map_dev(mdp, (-1-md->devnum)<< 6, 0);
+                       if (subarray)
+                               info = st->ss->container_content(st, subarray);
+                       else {
+                               info = xmalloc(sizeof(*info));
+                               st->ss->getinfo_super(st, info, NULL);
+                       }
+                       if (!info)
+                               continue;
+
+                       devid = devnm2devid(md->devnm);
+                       path = map_dev(major(devid), minor(devid), 0);
                        if (path == NULL ||
                            strncmp(path, "/dev/md/", 8) != 0) {
                                /* We would really like a name that provides
                                 * an MD_DEVNAME for udev.
                                 * The name needs to be unique both in /dev/md/
                                 * and in this mapfile.
-                                * It needs to match watch -I or -As would come
+                                * It needs to match what -I or -As would come
                                 * up with.
                                 * That means:
-                                *   Check if array is in mdadm.conf 
+                                *   Check if array is in mdadm.conf
                                 *        - if so use that.
                                 *   determine trustworthy from homehost etc
                                 *   find a unique name based on metadata name.
-                                *   
+                                *
                                 */
-                               struct mddev_ident_s *match = conf_match(&info, st);
+                               struct mddev_ident *match = conf_match(st, info,
+                                                                      NULL, 0,
+                                                                      NULL);
                                struct stat stb;
                                if (match && match->devname && match->devname[0] == '/') {
                                        path = match->devname;
@@ -415,14 +442,14 @@ void RebuildMap(void)
                                        if ((homehost == NULL ||
                                             st->ss->match_home(st, homehost) != 1) &&
                                            st->ss->match_home(st, "any") != 1 &&
-                                           (require_homehost
-                                            || ! conf_name_is_free(info.name)))
+                                           (require_homehost ||
+                                            !conf_name_is_free(info->name)))
                                                /* require a numeric suffix */
                                                unum = 0;
                                        else
                                                /* allow name to be used as-is if no conflict */
                                                unum = -1;
-                                       name = info.name;
+                                       name = info->name;
                                        if (!*name) {
                                                name = st->ss->name;
                                                if (!isdigit(name[strlen(name)-1]) &&
@@ -431,12 +458,19 @@ void RebuildMap(void)
                                                        sep = "";
                                                }
                                        }
-                                       if (strchr(name, ':'))
-                                               /* probably a uniquifying
+                                       if (strchr(name, ':')) {
+                                               /* Probably a uniquifying
                                                 * hostname prefix.  Allow
-                                                * without a suffix
+                                                * without a suffix, and strip
+                                                * hostname if it is us.
                                                 */
+                                               if (homehost && unum == -1 &&
+                                                   strncmp(name, homehost,
+                                                           strlen(homehost)) == 0 &&
+                                                   name[strlen(homehost)] == ':')
+                                                       name += strlen(homehost)+1;
                                                unum = -1;
+                                       }
 
                                        while (conflict) {
                                                if (unum >= 0)
@@ -454,20 +488,24 @@ void RebuildMap(void)
                                        path = namebuf;
                                }
                        }
-                       map_add(&map, md->devnum,
-                               info.text_version,
-                               info.uuid, path);
+                       map_add(&map, md->devnm,
+                               info->text_version,
+                               info->uuid, path);
                        st->ss->free_super(st);
+                       free(info);
                        break;
                }
                sysfs_free(sra);
        }
-       map_write(map);
+       /* Only trigger a change if we wrote a new map file */
+       if (map_write(map))
+               for (md = mdstat ; md ; md = md->next) {
+                       struct mdinfo *sra = sysfs_read(-1, md->devnm,
+                                                       GET_VERSION);
+                       if (sra)
+                               sysfs_uevent(sra, "change");
+                       sysfs_free(sra);
+               }
        map_free(map);
-       for (md = mdstat ; md ; md = md->next) {
-               struct mdinfo *sra = sysfs_read(-1, md->devnum, GET_VERSION);
-               sysfs_uevent(sra, "change");
-               sysfs_free(sra);
-       }
        free_mdstat(mdstat);
 }