]> git.ipfire.org Git - thirdparty/mdadm.git/blobdiff - policy.c
install: use BINDIR consistently to locate mdadm and mdmon
[thirdparty/mdadm.git] / policy.c
index abf9ee8ce3cd1e58bec689051a234c892a5ac55c..ef83621a93889f8b03a25729aef4b84e13694c62 100644 (file)
--- a/policy.c
+++ b/policy.c
  * particularly from a set of policy rules in mdadm.conf
  */
 
-void pol_new(struct dev_policy **pol, char *name, char *val, char *metadata)
+static void pol_new(struct dev_policy **pol, char *name, const char *val,
+                   const char *metadata)
 {
-       struct dev_policy *n = malloc(sizeof(*n));
+       struct dev_policy *n = xmalloc(sizeof(*n));
        const char *real_metadata = NULL;
        int i;
 
@@ -64,9 +65,9 @@ void pol_new(struct dev_policy **pol, char *name, char *val, char *metadata)
                                real_metadata = super1.name;
                }
                if (!real_metadata) {
-                       static char *prev = NULL;
+                       static const char *prev = NULL;
                        if (prev != metadata) {
-                               fprintf(stderr, Name ": metadata=%s unrecognised - ignoring rule\n",
+                               pr_err("metadata=%s unrecognised - ignoring rule\n",
                                        metadata);
                                prev = metadata;
                        }
@@ -137,8 +138,8 @@ static void pol_sort(struct dev_policy **pol)
                        if (p[next] == NULL ||
                            (p[1-next] != NULL &&
                             !(pol_lesseq(prev, p[1-next])
-                              ^pol_lesseq(p[1-next], p[next])
-                              ^pol_lesseq(p[next], prev)))
+                              ^pol_lesseq(prev, p[next])
+                              ^pol_lesseq(p[next], p[1-next])))
                                )
                                next = 1 - next;
 
@@ -194,30 +195,41 @@ static char *disk_path(struct mdinfo *disk)
        int prefix_len;
        DIR *by_path;
        char symlink[PATH_MAX] = "/dev/disk/by-path/";
+       char nm[PATH_MAX];
        struct dirent *ent;
+       int rv;
 
        by_path = opendir(symlink);
-       if (!by_path)
-               return NULL;
-       prefix_len = strlen(symlink);
-
-       while ((ent = readdir(by_path)) != NULL) {
-               if (ent->d_type != DT_LNK)
-                       continue;
-               strncpy(symlink + prefix_len,
-                       ent->d_name,
-                       sizeof(symlink) - prefix_len);
-               if (stat(symlink, &stb) < 0)
-                       continue;
-               if ((stb.st_mode & S_IFMT) != S_IFBLK)
-                       continue;
-               if (stb.st_rdev != makedev(disk->disk.major, disk->disk.minor))
-                       continue;
+       if (by_path) {
+               prefix_len = strlen(symlink);
+               while ((ent = readdir(by_path)) != NULL) {
+                       if (ent->d_type != DT_LNK)
+                               continue;
+                       strncpy(symlink + prefix_len,
+                                       ent->d_name,
+                                       sizeof(symlink) - prefix_len);
+                       if (stat(symlink, &stb) < 0)
+                               continue;
+                       if ((stb.st_mode & S_IFMT) != S_IFBLK)
+                               continue;
+                       if (stb.st_rdev != makedev(disk->disk.major, disk->disk.minor))
+                               continue;
+                       closedir(by_path);
+                       return xstrdup(ent->d_name);
+               }
                closedir(by_path);
-               return strdup(ent->d_name);
        }
-       closedir(by_path);
-       return NULL;
+       /* A NULL path isn't really acceptable - use the devname.. */
+       sprintf(symlink, "/sys/dev/block/%d:%d", disk->disk.major, disk->disk.minor);
+       rv = readlink(symlink, nm, sizeof(nm)-1);
+       if (rv > 0) {
+               char *dname;
+               nm[rv] = 0;
+               dname = strrchr(nm, '/');
+               if (dname)
+                       return xstrdup(dname + 1);
+       }
+       return xstrdup("unknown");
 }
 
 char type_part[] = "part";
@@ -244,13 +256,13 @@ static int pol_match(struct rule *rule, char *path, char *type)
                if (rule->name == rule_path) {
                        if (pathok == 0)
                                pathok = -1;
-                       if (fnmatch(rule->value, path, 0) == 0)
+                       if (path && fnmatch(rule->value, path, 0) == 0)
                                pathok = 1;
                }
                if (rule->name == rule_type) {
                        if (typeok == 0)
                                typeok = -1;
-                       if (strcmp(rule->value, type) == 0)
+                       if (type && strcmp(rule->value, type) == 0)
                                typeok = 1;
                }
                rule = rule->next;
@@ -269,7 +281,8 @@ static void pol_merge(struct dev_policy **pol, struct rule *rule)
 
        for (r = rule; r ; r = r->next)
                if (r->name == pol_act ||
-                   r->name == pol_domain)
+                   r->name == pol_domain ||
+                   r->name == pol_auto)
                        pol_new(pol, r->name, r->value, metadata);
 }
 
@@ -279,7 +292,10 @@ static int path_has_part(char *path, char **part)
         * if it does, place a pointer to "-pathNN"
         * in 'part'.
         */
-       int l = strlen(path);
+       int l;
+       if (!path)
+               return 0;
+       l = strlen(path);
        while (l > 1 && isdigit(path[l-1]))
                l--;
        if (l < 5 || strncmp(path+l-5, "-part", 5) != 0)
@@ -333,23 +349,14 @@ static int config_rules_has_path = 0;
 /*
  * most policy comes from a set policy rules that are
  * read from the config file.
- * disk_policy() gathers policy information for the
- * disk described in the given mdinfo (disk.{major,minor}).
+ * path_policy() gathers policy information for the
+ * disk described in the given a 'path' and a 'type'.
  */
-struct dev_policy *disk_policy(struct mdinfo *disk)
+struct dev_policy *path_policy(char *path, char *type)
 {
-       char *path = NULL;
-       char *type = disk_type(disk);
        struct pol_rule *rules;
        struct dev_policy *pol = NULL;
-
-       if (!type)
-               return NULL;
-       if (config_rules_has_path) {
-               path = disk_path(disk);
-               if (!path)
-                       return NULL;
-       }
+       int i;
 
        rules = config_rules;
 
@@ -367,12 +374,59 @@ struct dev_policy *disk_policy(struct mdinfo *disk)
                        }
                rules = rules->next;
        }
+
+       /* Now add any metadata-specific internal knowledge
+        * about this path
+        */
+       for (i=0; path && superlist[i]; i++)
+               if (superlist[i]->get_disk_controller_domain) {
+                       const char *d =
+                               superlist[i]->get_disk_controller_domain(path);
+                       if (d)
+                               pol_new(&pol, pol_domain, d, superlist[i]->name);
+               }
+
        pol_sort(&pol);
        pol_dedup(pol);
+       return pol;
+}
+
+void pol_add(struct dev_policy **pol,
+                   char *name, char *val,
+                   char *metadata)
+{
+       pol_new(pol, name, val, metadata);
+       pol_sort(pol);
+       pol_dedup(*pol);
+}
+
+/*
+ * disk_policy() gathers policy information for the
+ * disk described in the given mdinfo (disk.{major,minor}).
+ */
+struct dev_policy *disk_policy(struct mdinfo *disk)
+{
+       char *path = NULL;
+       char *type = disk_type(disk);
+       struct dev_policy *pol = NULL;
+
+       if (config_rules_has_path)
+               path = disk_path(disk);
+
+       pol = path_policy(path, type);
+
        free(path);
        return pol;
 }
 
+struct dev_policy *devid_policy(int dev)
+{
+       struct mdinfo disk;
+       disk.disk.major = major(dev);
+       disk.disk.minor = minor(dev);
+       return disk_policy(&disk);
+}
+
 /*
  * process policy rules read from config file.
  */
@@ -386,6 +440,7 @@ char rule_part[] = "part-policy";
 char pol_metadata[] = "metadata";
 char pol_act[] = "action";
 char pol_domain[] = "domain";
+char pol_auto[] = "auto";
 
 static int try_rule(char *w, char *name, struct rule **rp)
 {
@@ -394,10 +449,10 @@ static int try_rule(char *w, char *name, struct rule **rp)
        if (strncmp(w, name, len) != 0 ||
            w[len] != '=')
                return 0;
-       r = malloc(sizeof(*r));
+       r = xmalloc(sizeof(*r));
        r->next = *rp;
        r->name = name;
-       r->value = strdup(w+len+1);
+       r->value = xstrdup(w+len+1);
        r->dups = NULL;
        *rp = r;
        return 1;
@@ -411,7 +466,7 @@ void policyline(char *line, char *type)
        if (config_rules_end == NULL)
                config_rules_end = &config_rules;
 
-       pr = malloc(sizeof(*pr));
+       pr = xmalloc(sizeof(*pr));
        pr->type = type;
        pr->rule = NULL;
        for (w = dl_next(line); w != line ; w = dl_next(w)) {
@@ -420,14 +475,42 @@ void policyline(char *line, char *type)
                else if (! try_rule(w, rule_type, &pr->rule) &&
                         ! try_rule(w, pol_metadata, &pr->rule) &&
                         ! try_rule(w, pol_act, &pr->rule) &&
-                        ! try_rule(w, pol_domain, &pr->rule))
-                       fprintf(stderr, Name ": policy rule %s unrecognised and ignored\n",
+                        ! try_rule(w, pol_domain, &pr->rule) &&
+                        ! try_rule(w, pol_auto, &pr->rule))
+                       pr_err("policy rule %s unrecognised and ignored\n",
                                w);
        }
        pr->next = config_rules;
        config_rules = pr;
 }
 
+void policy_add(char *type, ...)
+{
+       va_list ap;
+       struct pol_rule *pr;
+       char *name, *val;
+
+       pr = xmalloc(sizeof(*pr));
+       pr->type = type;
+       pr->rule = NULL;
+
+       va_start(ap, type);
+       while ((name = va_arg(ap, char*)) != NULL) {
+               struct rule *r;
+
+               val = va_arg(ap, char*);
+               r = xmalloc(sizeof(*r));
+               r->next = pr->rule;
+               r->name = name;
+               r->value = xstrdup(val);
+               r->dups = NULL;
+               pr->rule = r;
+       }
+       pr->next = config_rules;
+       config_rules = pr;
+       va_end(ap);
+}
+
 void policy_free(void)
 {
        while (config_rules) {
@@ -459,3 +542,373 @@ void dev_policy_free(struct dev_policy *p)
                free(t);
        }
 }
+
+static enum policy_action map_act(const char *act)
+{
+       if (strcmp(act, "include") == 0)
+               return act_include;
+       if (strcmp(act, "re-add") == 0)
+               return act_re_add;
+       if (strcmp(act, "spare") == 0)
+               return act_spare;
+       if (strcmp(act, "spare-same-slot") == 0)
+               return act_spare_same_slot;
+       if (strcmp(act, "force-spare") == 0)
+               return act_force_spare;
+       return act_err;
+}
+
+static enum policy_action policy_action(struct dev_policy *plist, const char *metadata)
+{
+       enum policy_action rv = act_default;
+       struct dev_policy *p;
+
+       plist = pol_find(plist, pol_act);
+       pol_for_each(p, plist, metadata) {
+               enum policy_action a = map_act(p->value);
+               if (a > rv)
+                       rv = a;
+       }
+       return rv;
+}
+
+int policy_action_allows(struct dev_policy *plist, const char *metadata, enum policy_action want)
+{
+       enum policy_action act = policy_action(plist, metadata);
+
+       if (act == act_err)
+               return 0;
+       return (act >= want);
+}
+
+int disk_action_allows(struct mdinfo *disk, const char *metadata, enum policy_action want)
+{
+       struct dev_policy *pol = disk_policy(disk);
+       int rv = policy_action_allows(pol, metadata, want);
+
+       dev_policy_free(pol);
+       return rv;
+}
+
+/* Domain policy:
+ * Any device can have a list of domains asserted by different policy
+ * statements.
+ * An array also has a list of domains comprising all the domains of
+ * all the devices in an array.
+ * Where an array has a spare-group, that becomes an addition domain for
+ * every device in the array and thus for the array.
+ *
+ * We keep the list of domains in a sorted linked list
+ * As dev policies are already sorted, this is fairly easy to manage.
+ */
+
+static struct domainlist **domain_merge_one(struct domainlist **domp,
+                                           const char *domain)
+{
+       /* merge a domain name into a sorted list and return the
+        * location of the insertion or match
+        */
+       struct domainlist *dom = *domp;
+
+       while (dom && strcmp(dom->dom, domain) < 0) {
+               domp = &dom->next;
+               dom = *domp;
+       }
+       if (dom == NULL || strcmp(dom->dom, domain) != 0) {
+               dom = xmalloc(sizeof(*dom));
+               dom->next = *domp;
+               dom->dom = domain;
+               *domp = dom;
+       }
+       return domp;
+}
+
+#if (DEBUG)
+void dump_policy(struct dev_policy *policy)
+{
+       while (policy) {
+               dprintf("policy: %p name: %s value: %s metadata: %s\n",
+                       policy,
+                       policy->name,
+                       policy->value,
+                       policy->metadata);
+               policy = policy->next;
+       }
+}
+#endif
+
+void domain_merge(struct domainlist **domp, struct dev_policy *pollist,
+                        const char *metadata)
+{
+       /* Add to 'domp' all the domains in pol that apply to 'metadata'
+        * which are not already in domp
+        */
+       struct dev_policy *pol;
+       pollist = pol_find(pollist, pol_domain);
+       pol_for_each(pol, pollist, metadata)
+               domain_merge_one(domp, pol->value);
+}
+
+int domain_test(struct domainlist *dom, struct dev_policy *pol,
+               const char *metadata)
+{
+       /* Check that all domains in pol (for metadata) are also in
+        * dom.  Both lists are sorted.
+        * If pol has no domains, we don't really know about this device
+        * so we allow caller to choose:
+        * -1:  has no domains
+        *  0:  has domains, not all match
+        *  1:  has domains, all match
+        */
+       int found_any = -1;
+       struct dev_policy *p;
+
+       pol = pol_find(pol, pol_domain);
+       pol_for_each(p, pol, metadata) {
+               found_any = 1;
+               while (dom && strcmp(dom->dom, p->value) < 0)
+                       dom = dom->next;
+               if (!dom || strcmp(dom->dom, p->value) != 0)
+                       return 0;
+       }
+       return found_any;
+}
+
+void domainlist_add_dev(struct domainlist **dom, int devid, const char *metadata)
+{
+       struct dev_policy *pol = devid_policy(devid);
+       domain_merge(dom, pol, metadata);
+       dev_policy_free(pol);
+}
+
+struct domainlist *domain_from_array(struct mdinfo *mdi, const char *metadata)
+{
+       struct domainlist *domlist = NULL;
+
+       if (!mdi)
+               return NULL;
+       for (mdi = mdi->devs ; mdi ; mdi = mdi->next)
+               domainlist_add_dev(&domlist, makedev(mdi->disk.major,
+                                                    mdi->disk.minor),
+                                  metadata);
+
+       return domlist;
+}
+
+void domain_add(struct domainlist **domp, char *domain)
+{
+       domain_merge_one(domp, domain);
+}
+
+void domain_free(struct domainlist *dl)
+{
+       while (dl) {
+               struct domainlist *head = dl;
+               dl = dl->next;
+               free(head);
+       }
+}
+
+/*
+ * same-path policy.
+ * Some policy decisions are guided by knowledge of which
+ * array previously owned the device at a given physical location (path).
+ * When removing a device from an array we might record the array against
+ * the path, and when finding a new device, we might look for which
+ * array previously used that path.
+ *
+ * The 'array' is described by a map_ent, and the path by a the disk in an
+ * mdinfo, or a string.
+ */
+
+void policy_save_path(char *id_path, struct map_ent *array)
+{
+       char path[PATH_MAX];
+       FILE *f = NULL;
+
+       if (mkdir(FAILED_SLOTS_DIR, S_IRWXU) < 0 && errno != EEXIST) {
+               pr_err("can't create file to save path "
+                       "to old disk: %s\n", strerror(errno));
+               return;
+       }
+
+       snprintf(path, PATH_MAX, FAILED_SLOTS_DIR "/%s", id_path);
+       f = fopen(path, "w");
+       if (!f) {
+               pr_err("can't create file to"
+                       " save path to old disk: %s\n",
+                       strerror(errno));
+               return;
+       }
+
+       if (fprintf(f, "%s %08x:%08x:%08x:%08x\n",
+                   array->metadata,
+                   array->uuid[0], array->uuid[1],
+                   array->uuid[2], array->uuid[3]) <= 0)
+               pr_err("Failed to write to "
+                      "<id_path> cookie\n");
+
+       fclose(f);
+}
+
+int policy_check_path(struct mdinfo *disk, struct map_ent *array)
+{
+       char path[PATH_MAX];
+       FILE *f = NULL;
+       char *id_path = disk_path(disk);
+       int rv;
+
+       if (!id_path)
+               return 0;
+
+       snprintf(path, PATH_MAX, FAILED_SLOTS_DIR "/%s", id_path);
+       f = fopen(path, "r");
+       if (!f) {
+               free(id_path);
+               return 0;
+       }
+
+       rv = fscanf(f, " %s %x:%x:%x:%x\n",
+                   array->metadata,
+                   array->uuid,
+                   array->uuid+1,
+                   array->uuid+2,
+                   array->uuid+3);
+       fclose(f);
+       free(id_path);
+       return rv == 5;
+}
+
+/* invocation of udev rule file */
+char udev_template_start[] =
+"# do not edit this file, it is automatically generated by mdadm\n"
+"\n";
+
+/* find rule named rule_type and return its value */
+char *find_rule(struct rule *rule, char *rule_type)
+{
+       while (rule) {
+               if (rule->name == rule_type)
+                       return rule->value;
+
+               rule = rule->next;
+       }
+       return NULL;
+}
+
+#define UDEV_RULE_FORMAT \
+"ACTION==\"add\", SUBSYSTEM==\"block\", " \
+"ENV{DEVTYPE}==\"%s\", ENV{ID_PATH}==\"%s\", " \
+"RUN+=\"" BINDIR "/mdadm --incremental $env{DEVNAME}\"\n"
+
+#define UDEV_RULE_FORMAT_NOTYPE \
+"ACTION==\"add\", SUBSYSTEM==\"block\", " \
+"ENV{ID_PATH}==\"%s\", " \
+"RUN+=\"" BINDIR "/mdadm --incremental $env{DEVNAME}\"\n"
+
+/* Write rule in the rule file. Use format from UDEV_RULE_FORMAT */
+int write_rule(struct rule *rule, int fd, int force_part)
+{
+       char line[1024];
+       char *pth = find_rule(rule, rule_path);
+       char *typ = find_rule(rule, rule_type);
+       if (!pth)
+               return -1;
+
+       if (force_part)
+               typ = type_part;
+       if (typ)
+               snprintf(line, sizeof(line) - 1, UDEV_RULE_FORMAT, typ, pth);
+       else
+               snprintf(line, sizeof(line) - 1, UDEV_RULE_FORMAT_NOTYPE, pth);
+       return write(fd, line, strlen(line)) == (int)strlen(line);
+}
+
+/* Generate single entry in udev rule basing on POLICY line found in config
+ * file. Take only those with paths, only first occurrence if paths are equal
+ * and if actions supports handling of spares (>=act_spare_same_slot)
+ */
+int generate_entries(int fd)
+{
+       struct pol_rule *loop, *dup;
+       char *loop_value, *dup_value;
+       int duplicate;
+
+       for (loop = config_rules; loop; loop = loop->next) {
+               if (loop->type != rule_policy && loop->type != rule_part)
+                       continue;
+               duplicate = 0;
+
+               /* only policies with paths and with actions supporting
+                * bare disks are considered */
+               loop_value = find_rule(loop->rule, pol_act);
+               if (!loop_value || map_act(loop_value) < act_spare_same_slot)
+                       continue;
+               loop_value = find_rule(loop->rule, rule_path);
+               if (!loop_value)
+                       continue;
+               for (dup = config_rules; dup != loop; dup = dup->next) {
+                       if (dup->type != rule_policy && loop->type != rule_part)
+                               continue;
+                       dup_value = find_rule(dup->rule, pol_act);
+                       if (!dup_value || map_act(dup_value) < act_spare_same_slot)
+                               continue;
+                       dup_value = find_rule(dup->rule, rule_path);
+                       if (!dup_value)
+                               continue;
+                       if (strcmp(loop_value, dup_value) == 0) {
+                               duplicate = 1;
+                               break;
+                       }
+               }
+
+               /* not a dup or first occurrence */
+               if (!duplicate)
+                       if (!write_rule(loop->rule, fd, loop->type == rule_part) )
+                               return 0;
+       }
+       return 1;
+}
+
+/* Write_rules routine creates dynamic udev rules used to handle
+ * hot-plug events for bare devices (and making them spares)
+ */
+int Write_rules(char *rule_name)
+{
+       int fd;
+       char udev_rule_file[PATH_MAX];
+
+       if (rule_name) {
+               strncpy(udev_rule_file, rule_name, sizeof(udev_rule_file) - 6);
+               udev_rule_file[sizeof(udev_rule_file) - 6] = '\0';
+               strcat(udev_rule_file, ".temp");
+               fd = creat(udev_rule_file,
+                          S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+               if (fd == -1)
+                       return 1;
+       } else
+               fd = 1;
+
+       /* write static invocation */
+       if (write(fd, udev_template_start,
+                 sizeof(udev_template_start) - 1)
+           != (int)sizeof(udev_template_start)-1)
+               goto abort;
+
+       /* iterate, if none created or error occurred, remove file */
+       if (generate_entries(fd) < 0)
+               goto abort;
+
+       fsync(fd);
+       if (rule_name) {
+               close(fd);
+               rename(udev_rule_file, rule_name);
+       }
+       return 0;
+abort:
+       if (rule_name) {
+               close(fd);
+               unlink(udev_rule_file);
+       }
+       return 1;
+}