]> git.ipfire.org Git - thirdparty/mdadm.git/blobdiff - mapfile.c
Remove scattered checks for malloc success.
[thirdparty/mdadm.git] / mapfile.c
index d47fde1463b8adf9758e9391f58fe79967cc8633..fa238832ab6ba633ef08960125f37242945cfd09 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
@@ -28,7 +28,7 @@
  *           Australia
  */
 
-/* /var/run/mdadm.map is used to track arrays being created in --incremental
+/* 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.
  *
  *  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  /lib/initrw/madam/map
- * The last can easily be change at compile to e.g. somewhere in /dev.
- * 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 "/" ALT_MAPFILE)
+
+#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
 };
-char *mapdir[3] = { VAR_RUN, NULL, ALT_RUN };
 
-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;
-               if ((mapmode[modenum] & O_CREAT) &&
-                   mapdir[modenum])
-                       /* Attempt to create directory, don't worry about
-                        * failure.
-                        */
-                       mkdir(mapdir[modenum], 0755);
-               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;
 }
 
@@ -87,9 +80,8 @@ 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;
@@ -109,20 +101,20 @@ 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) {
@@ -130,6 +122,15 @@ 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);
@@ -140,22 +141,37 @@ 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]);
        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)
 {
-       struct map_ent *me = malloc(sizeof(*me));
+       struct map_ent *me = xmalloc(sizeof(*me));
 
        me->devnum = devnum;
        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;
@@ -169,14 +185,13 @@ void map_read(struct map_ent **melp)
        int devnum, uuid[4];
        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;
@@ -222,7 +237,8 @@ int map_update(struct map_ent **mpp, int devnum, char *metadata,
                        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)
@@ -251,6 +267,16 @@ void map_delete(struct map_ent **mapp, int devnum)
        }
 }
 
+void map_remove(struct map_ent **mapp, int devnum)
+{
+       if (devnum == NoMdDev)
+               return;
+
+       map_delete(mapp, devnum);
+       map_write(*mapp);
+       map_free(*mapp);
+}
+
 struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
 {
        struct map_ent *mp;
@@ -313,31 +339,20 @@ 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)
@@ -358,7 +373,7 @@ 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->devnum, GET_DEVS);
                struct mdinfo *sd;
 
                if (!sra)
@@ -370,8 +385,9 @@ void RebuildMap(void)
                        int dfd;
                        int ok;
                        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);
@@ -381,13 +397,16 @@ 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);
+                       info = st->ss->container_content(st, subarray);
+                       if (!info)
+                               continue;
+
                        if (md->devnum >= 0)
                                path = map_dev(MD_MAJOR, md->devnum, 0);
                        else
@@ -407,7 +426,9 @@ void RebuildMap(void)
                                 *   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;
@@ -425,13 +446,13 @@ void RebuildMap(void)
                                             st->ss->match_home(st, homehost) != 1) &&
                                            st->ss->match_home(st, "any") != 1 &&
                                            (require_homehost
-                                            || ! conf_name_is_free(info.name)))
+                                            || ! 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]) &&
@@ -464,9 +485,10 @@ void RebuildMap(void)
                                }
                        }
                        map_add(&map, md->devnum,
-                               info.text_version,
-                               info.uuid, path);
+                               info->text_version,
+                               info->uuid, path);
                        st->ss->free_super(st);
+                       free(info);
                        break;
                }
                sysfs_free(sra);
@@ -476,7 +498,8 @@ void RebuildMap(void)
                for (md = mdstat ; md ; md = md->next) {
                        struct mdinfo *sra = sysfs_read(-1, md->devnum,
                                                        GET_VERSION);
-                       sysfs_uevent(sra, "change");
+                       if (sra)
+                               sysfs_uevent(sra, "change");
                        sysfs_free(sra);
                }
        map_free(map);