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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:55:34 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:55:34 +0000
commit7f1d6c8fec531fa1762d6d65576aecbee837982c (patch)
treeb37177c380fa30d0336aad7cac9c72035523206a /policy.c
parentInitial commit. (diff)
downloadmdadm-7f1d6c8fec531fa1762d6d65576aecbee837982c.tar.xz
mdadm-7f1d6c8fec531fa1762d6d65576aecbee837982c.zip
Adding upstream version 4.3.upstream/4.3
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'policy.c')
-rw-r--r--policy.c931
1 files changed, 931 insertions, 0 deletions
diff --git a/policy.c b/policy.c
new file mode 100644
index 0000000..eee9ef6
--- /dev/null
+++ b/policy.c
@@ -0,0 +1,931 @@
+/*
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2001-2009 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>
+ */
+
+#include "mdadm.h"
+#include <dirent.h>
+#include <fnmatch.h>
+#include <ctype.h>
+#include "dlink.h"
+/*
+ * Policy module for mdadm.
+ * A policy statement about a device lists a set of values for each
+ * of a set of names. Each value can have a metadata type as context.
+ *
+ * names include:
+ * action - the actions that can be taken on hot-plug
+ * domain - the domain(s) that the device is part of
+ *
+ * Policy information is extracted from various sources, but
+ * particularly from a set of policy rules in mdadm.conf
+ */
+
+static void pol_new(struct dev_policy **pol, char *name, const char *val,
+ const char *metadata)
+{
+ struct dev_policy *n = xmalloc(sizeof(*n));
+ const char *real_metadata = NULL;
+ int i;
+
+ n->name = name;
+ n->value = val;
+
+ /* We need to normalise the metadata name */
+ if (metadata) {
+ for (i = 0; superlist[i] ; i++)
+ if (strcmp(metadata, superlist[i]->name) == 0) {
+ real_metadata = superlist[i]->name;
+ break;
+ }
+ if (!real_metadata) {
+ if (strcmp(metadata, "1") == 0 ||
+ strcmp(metadata, "1.0") == 0 ||
+ strcmp(metadata, "1.1") == 0 ||
+ strcmp(metadata, "1.2") == 0)
+ real_metadata = super1.name;
+ }
+ if (!real_metadata) {
+ static const char *prev = NULL;
+ if (prev != metadata) {
+ pr_err("metadata=%s unrecognised - ignoring rule\n",
+ metadata);
+ prev = metadata;
+ }
+ real_metadata = "unknown";
+ }
+ }
+
+ n->metadata = real_metadata;
+ n->next = *pol;
+ *pol = n;
+}
+
+static int pol_lesseq(struct dev_policy *a, struct dev_policy *b)
+{
+ int cmp;
+
+ if (a->name < b->name)
+ return 1;
+ if (a->name > b->name)
+ return 0;
+
+ cmp = strcmp(a->value, b->value);
+ if (cmp < 0)
+ return 1;
+ if (cmp > 0)
+ return 0;
+
+ return (a->metadata <= b->metadata);
+}
+
+static void pol_sort(struct dev_policy **pol)
+{
+ /* sort policy list in *pol by name/metadata/value
+ * using merge sort
+ */
+
+ struct dev_policy *pl[2];
+ pl[0] = *pol;
+ pl[1] = NULL;
+
+ do {
+ struct dev_policy **plp[2], *p[2];
+ int curr = 0;
+ struct dev_policy nul = { NULL, NULL, NULL, NULL };
+ struct dev_policy *prev = &nul;
+ int next = 0;
+
+ /* p[] are the two lists that we are merging.
+ * plp[] are the ends of the two lists we create
+ * from the merge.
+ * 'curr' is which of plp[] that we are currently
+ * adding items to.
+ * 'next' is which if p[] we will take the next
+ * item from.
+ * 'prev' is that last value, which was placed in
+ * plp[curr].
+ */
+ plp[0] = &pl[0];
+ plp[1] = &pl[1];
+ p[0] = pl[0];
+ p[1] = pl[1];
+
+ /* take least of p[0] and p[1]
+ * if it is larger than prev, add to
+ * plp[curr], else swap curr then add
+ */
+ while (p[0] || p[1]) {
+ if (p[next] == NULL ||
+ (p[1-next] != NULL &&
+ !(pol_lesseq(prev, p[1-next])
+ ^pol_lesseq(prev, p[next])
+ ^pol_lesseq(p[next], p[1-next])))
+ )
+ next = 1 - next;
+
+ if (!pol_lesseq(prev, p[next]))
+ curr = 1 - curr;
+
+ *plp[curr] = prev = p[next];
+ plp[curr] = &p[next]->next;
+ p[next] = p[next]->next;
+ }
+ *plp[0] = NULL;
+ *plp[1] = NULL;
+ } while (pl[0] && pl[1]);
+ if (pl[0])
+ *pol = pl[0];
+ else
+ *pol = pl[1];
+}
+
+static void pol_dedup(struct dev_policy *pol)
+{
+ /* This is a sorted list - remove duplicates. */
+ while (pol && pol->next) {
+ if (pol_lesseq(pol->next, pol)) {
+ struct dev_policy *tmp = pol->next;
+ pol->next = tmp->next;
+ free(tmp);
+ } else
+ pol = pol->next;
+ }
+}
+
+/*
+ * pol_find finds the first entry in the policy
+ * list to match name.
+ * If it returns non-NULL there is at least one
+ * value, but how many can only be found by
+ * iterating through the list.
+ */
+struct dev_policy *pol_find(struct dev_policy *pol, char *name)
+{
+ while (pol && pol->name < name)
+ pol = pol->next;
+
+ if (!pol || pol->name != name)
+ return NULL;
+ return pol;
+}
+
+static char **disk_paths(struct mdinfo *disk)
+{
+ struct stat stb;
+ int prefix_len;
+ DIR *by_path;
+ char symlink[PATH_MAX] = "/dev/disk/by-path/";
+ char **paths;
+ int cnt = 0;
+ struct dirent *ent;
+
+ paths = xmalloc(sizeof(*paths) * (cnt+1));
+
+ by_path = opendir(symlink);
+ 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;
+ paths[cnt++] = xstrdup(ent->d_name);
+ paths = xrealloc(paths, sizeof(*paths) * (cnt+1));
+ }
+ closedir(by_path);
+ }
+ paths[cnt] = NULL;
+ return paths;
+}
+
+char type_part[] = "part";
+char type_disk[] = "disk";
+static char *disk_type(struct mdinfo *disk)
+{
+ char buf[30+20+20];
+ struct stat stb;
+ sprintf(buf, "/sys/dev/block/%d:%d/partition",
+ disk->disk.major, disk->disk.minor);
+ if (stat(buf, &stb) == 0)
+ return type_part;
+ else
+ return type_disk;
+}
+
+static int path_has_part(char *path, char **part)
+{
+ /* check if path ends with "-partNN" and
+ * if it does, place a pointer to "-pathNN"
+ * in 'part'.
+ */
+ 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)
+ return 0;
+ *part = path+l-5;
+ return 1;
+}
+
+static int pol_match(struct rule *rule, char **paths, char *type, char **part)
+{
+ /* Check if this rule matches on any path and type.
+ * If 'part' is not NULL, then 'path' must end in -partN, which
+ * we ignore for matching, and return in *part on success.
+ */
+ int pathok = 0; /* 0 == no path, 1 == match, -1 == no match yet */
+ int typeok = 0;
+
+ for (; rule; rule = rule->next) {
+ if (rule->name == rule_path) {
+ char *p = NULL;
+ int i;
+ if (pathok == 0)
+ pathok = -1;
+ if (!paths)
+ continue;
+ for (i = 0; paths[i]; i++) {
+ if (part) {
+ if (!path_has_part(paths[i], &p))
+ continue;
+ *p = '\0';
+ *part = p+1;
+ }
+ if (fnmatch(rule->value, paths[i], 0) == 0)
+ pathok = 1;
+ if (part)
+ *p = '-';
+ }
+ }
+ if (rule->name == rule_type) {
+ if (typeok == 0)
+ typeok = -1;
+ if (type && strcmp(rule->value, type) == 0)
+ typeok = 1;
+ }
+ }
+ return pathok >= 0 && typeok >= 0;
+}
+
+static void pol_merge(struct dev_policy **pol, struct rule *rule)
+{
+ /* copy any name assignments from rule into pol */
+ struct rule *r;
+ char *metadata = NULL;
+ for (r = rule; r ; r = r->next)
+ if (r->name == pol_metadata)
+ metadata = r->value;
+
+ for (r = rule; r ; r = r->next)
+ if (r->name == pol_act ||
+ r->name == pol_domain ||
+ r->name == pol_auto)
+ pol_new(pol, r->name, r->value, metadata);
+}
+
+static void pol_merge_part(struct dev_policy **pol, struct rule *rule, char *part)
+{
+ /* copy any name assignments from rule into pol, appending
+ * -part to any domain. The string with -part appended is
+ * stored with the rule so it has a lifetime to match
+ * the rule.
+ */
+ struct rule *r;
+ char *metadata = NULL;
+ for (r = rule; r ; r = r->next)
+ if (r->name == pol_metadata)
+ metadata = r->value;
+
+ for (r = rule; r ; r = r->next) {
+ if (r->name == pol_act)
+ pol_new(pol, r->name, r->value, metadata);
+ else if (r->name == pol_domain) {
+ char *dom;
+ int len;
+ if (r->dups == NULL)
+ r->dups = dl_head();
+ len = strlen(r->value);
+ for (dom = dl_next(r->dups); dom != r->dups;
+ dom = dl_next(dom))
+ if (strcmp(dom+len+1, part)== 0)
+ break;
+ if (dom == r->dups) {
+ char *newdom = dl_strndup(
+ r->value, len + 1 + strlen(part));
+ strcat(strcat(newdom, "-"), part);
+ dl_add(r->dups, newdom);
+ dom = newdom;
+ }
+ pol_new(pol, r->name, dom, metadata);
+ }
+ }
+}
+
+static struct pol_rule *config_rules = NULL;
+static struct pol_rule **config_rules_end = NULL;
+static int config_rules_has_path = 0;
+
+/*
+ * most policy comes from a set policy rules that are
+ * read from the config file.
+ * path_policy() gathers policy information for the
+ * disk described in the given a 'path' and a 'type'.
+ */
+struct dev_policy *path_policy(char **paths, char *type)
+{
+ struct pol_rule *rules;
+ struct dev_policy *pol = NULL;
+ int i;
+
+ rules = config_rules;
+
+ while (rules) {
+ char *part = NULL;
+ if (rules->type == rule_policy)
+ if (pol_match(rules->rule, paths, type, NULL))
+ pol_merge(&pol, rules->rule);
+ if (rules->type == rule_part && strcmp(type, type_part) == 0)
+ if (pol_match(rules->rule, paths, type_disk, &part))
+ pol_merge_part(&pol, rules->rule, part);
+ rules = rules->next;
+ }
+
+ /* Now add any metadata-specific internal knowledge
+ * about this path
+ */
+ for (i=0; paths && paths[0] && superlist[i]; i++)
+ if (superlist[i]->get_disk_controller_domain) {
+ const char *d =
+ superlist[i]->get_disk_controller_domain(
+ paths[0]);
+ 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);
+}
+
+static void free_paths(char **paths)
+{
+ int i;
+
+ if (!paths)
+ return;
+
+ for (i = 0; paths[i]; i++)
+ free(paths[i]);
+ free(paths);
+}
+
+/*
+ * 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 **paths = NULL;
+ char *type = disk_type(disk);
+ struct dev_policy *pol = NULL;
+
+ if (config_rules_has_path)
+ paths = disk_paths(disk);
+
+ pol = path_policy(paths, type);
+
+ free_paths(paths);
+ 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.
+ */
+
+char rule_path[] = "path";
+char rule_type[] = "type";
+
+char rule_policy[] = "policy";
+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)
+{
+ struct rule *r;
+ int len = strlen(name);
+ if (strncmp(w, name, len) != 0 ||
+ w[len] != '=')
+ return 0;
+ r = xmalloc(sizeof(*r));
+ r->next = *rp;
+ r->name = name;
+ r->value = xstrdup(w+len+1);
+ r->dups = NULL;
+ *rp = r;
+ return 1;
+}
+
+void policyline(char *line, char *type)
+{
+ struct pol_rule *pr;
+ char *w;
+
+ if (config_rules_end == NULL)
+ config_rules_end = &config_rules;
+
+ pr = xmalloc(sizeof(*pr));
+ pr->type = type;
+ pr->rule = NULL;
+ for (w = dl_next(line); w != line ; w = dl_next(w)) {
+ if (try_rule(w, rule_path, &pr->rule))
+ config_rules_has_path = 1;
+ 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) &&
+ ! 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) {
+ struct pol_rule *pr = config_rules;
+ struct rule *r;
+
+ config_rules = config_rules->next;
+
+ for (r = pr->rule; r; ) {
+ struct rule *next = r->next;
+ free(r->value);
+ if (r->dups)
+ free_line(r->dups);
+ free(r);
+ r = next;
+ }
+ free(pr);
+ }
+ config_rules_end = NULL;
+ config_rules_has_path = 0;
+}
+
+void dev_policy_free(struct dev_policy *p)
+{
+ struct dev_policy *t;
+ while (p) {
+ t = p;
+ p = p->next;
+ 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;
+ int has_one_domain = 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;
+ if (has_one_domain && metadata && strcmp(metadata, "imsm") == 0)
+ found_any = -1;
+ has_one_domain = 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, "%20s %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_paths = disk_paths(disk);
+ int i;
+ int rv = 0;
+
+ for (i = 0; id_paths[i]; i++) {
+ snprintf(path, PATH_MAX, FAILED_SLOTS_DIR "/%s", id_paths[i]);
+ f = fopen(path, "r");
+ if (!f)
+ continue;
+
+ rv = fscanf(f, " %20s %x:%x:%x:%x\n",
+ array->metadata,
+ array->uuid,
+ array->uuid+1,
+ array->uuid+2,
+ array->uuid+3);
+ fclose(f);
+ break;
+ }
+ free_paths(id_paths);
+ 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;
+}