Imported Upstream version 0.7.0
[platform/upstream/multipath-tools.git] / multipathd / main.c
index 6e33b11..0c61caa 100644 (file)
@@ -7,7 +7,7 @@
 #include <unistd.h>
 #include <sys/stat.h>
 #include <libdevmapper.h>
-#include <wait.h>
+#include <sys/wait.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <linux/oom.h>
 #include <libudev.h>
-#include <mpath_persist.h>
+#include <urcu.h>
+#ifdef USE_SYSTEMD
+#include <systemd/sd-daemon.h>
+#endif
+#include <semaphore.h>
+#include <time.h>
+#include <stdbool.h>
+
+/*
+ * libmultipath
+ */
+#include "time-util.h"
 
 /*
  * libcheckers
  */
-#include <checkers.h>
+#include "checkers.h"
+
+#ifdef USE_SYSTEMD
+static int use_watchdog;
+#endif
+
+int uxsock_timeout;
 
 /*
  * libmultipath
  */
-#include <parser.h>
-#include <vector.h>
-#include <memory.h>
-#include <config.h>
-#include <util.h>
-#include <hwtable.h>
-#include <defaults.h>
-#include <structs.h>
-#include <blacklist.h>
-#include <structs_vec.h>
-#include <dmparser.h>
-#include <devmapper.h>
-#include <sysfs.h>
-#include <dict.h>
-#include <discovery.h>
-#include <debug.h>
-#include <propsel.h>
-#include <uevent.h>
-#include <switchgroup.h>
-#include <print.h>
-#include <configure.h>
-#include <prio.h>
-#include <pgpolicies.h>
-#include <uevent.h>
+#include "parser.h"
+#include "vector.h"
+#include "memory.h"
+#include "config.h"
+#include "util.h"
+#include "hwtable.h"
+#include "defaults.h"
+#include "structs.h"
+#include "blacklist.h"
+#include "structs_vec.h"
+#include "dmparser.h"
+#include "devmapper.h"
+#include "sysfs.h"
+#include "dict.h"
+#include "discovery.h"
+#include "debug.h"
+#include "propsel.h"
+#include "uevent.h"
+#include "switchgroup.h"
+#include "print.h"
+#include "configure.h"
+#include "prio.h"
+#include "wwids.h"
+#include "pgpolicies.h"
+#include "uevent.h"
+#include "log.h"
+
+#include "mpath_cmd.h"
+#include "mpath_persist.h"
+
+#include "prioritizers/alua_rtpg.h"
 
 #include "main.h"
 #include "pidfile.h"
@@ -60,6 +84,8 @@
 #include "cli_handlers.h"
 #include "lock.h"
 #include "waiter.h"
+#include "wwids.h"
+#include "../third-party/valgrind/drd.h"
 
 #define FILE_NAME_SIZE 256
 #define CMDSIZE 160
@@ -80,24 +106,135 @@ struct mpath_event_param
 
 unsigned int mpath_mx_alloc_len;
 
-pthread_cond_t exit_cond = PTHREAD_COND_INITIALIZER;
-pthread_mutex_t exit_mutex = PTHREAD_MUTEX_INITIALIZER;
-
 int logsink;
-enum daemon_status running_state;
+int verbosity;
+int bindings_read_only;
+int ignore_new_devs;
+enum daemon_status running_state = DAEMON_INIT;
 pid_t daemon_pid;
+pthread_mutex_t config_lock = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t config_cond;
 
 /*
  * global copy of vecs for use in sig handlers
  */
 struct vectors * gvecs;
 
+struct udev * udev;
+
+struct config *multipath_conf;
+
+/* Local variables */
+static volatile sig_atomic_t exit_sig;
+static volatile sig_atomic_t reconfig_sig;
+static volatile sig_atomic_t log_reset_sig;
+
+const char *
+daemon_status(void)
+{
+       switch (running_state) {
+       case DAEMON_INIT:
+               return "init";
+       case DAEMON_START:
+               return "startup";
+       case DAEMON_CONFIGURE:
+               return "configure";
+       case DAEMON_IDLE:
+               return "idle";
+       case DAEMON_RUNNING:
+               return "running";
+       case DAEMON_SHUTDOWN:
+               return "shutdown";
+       }
+       return NULL;
+}
+
+/*
+ * I love you too, systemd ...
+ */
+const char *
+sd_notify_status(void)
+{
+       switch (running_state) {
+       case DAEMON_INIT:
+               return "STATUS=init";
+       case DAEMON_START:
+               return "STATUS=startup";
+       case DAEMON_CONFIGURE:
+               return "STATUS=configure";
+       case DAEMON_IDLE:
+               return "STATUS=idle";
+       case DAEMON_RUNNING:
+               return "STATUS=running";
+       case DAEMON_SHUTDOWN:
+               return "STATUS=shutdown";
+       }
+       return NULL;
+}
+
+static void config_cleanup(void *arg)
+{
+       pthread_mutex_unlock(&config_lock);
+}
+
+void post_config_state(enum daemon_status state)
+{
+       pthread_mutex_lock(&config_lock);
+       if (state != running_state) {
+               running_state = state;
+               pthread_cond_broadcast(&config_cond);
+#ifdef USE_SYSTEMD
+               sd_notify(0, sd_notify_status());
+#endif
+       }
+       pthread_mutex_unlock(&config_lock);
+}
+
+int set_config_state(enum daemon_status state)
+{
+       int rc = 0;
+
+       pthread_cleanup_push(config_cleanup, NULL);
+       pthread_mutex_lock(&config_lock);
+       if (running_state != state) {
+               if (running_state != DAEMON_IDLE) {
+                       struct timespec ts;
+
+                       clock_gettime(CLOCK_MONOTONIC, &ts);
+                       ts.tv_sec += 1;
+                       rc = pthread_cond_timedwait(&config_cond,
+                                                   &config_lock, &ts);
+               }
+               if (!rc) {
+                       running_state = state;
+                       pthread_cond_broadcast(&config_cond);
+#ifdef USE_SYSTEMD
+                       sd_notify(0, sd_notify_status());
+#endif
+               }
+       }
+       pthread_cleanup_pop(1);
+       return rc;
+}
+
+struct config *get_multipath_config(void)
+{
+       rcu_read_lock();
+       return rcu_dereference(multipath_conf);
+}
+
+void put_multipath_config(struct config *conf)
+{
+       rcu_read_unlock();
+}
+
 static int
 need_switch_pathgroup (struct multipath * mpp, int refresh)
 {
        struct pathgroup * pgp;
        struct path * pp;
        unsigned int i, j;
+       struct config *conf;
 
        if (!mpp || mpp->pgfailback == -FAILBACK_MANUAL)
                return 0;
@@ -105,10 +242,18 @@ need_switch_pathgroup (struct multipath * mpp, int refresh)
        /*
         * Refresh path priority values
         */
-       if (refresh)
-               vector_foreach_slot (mpp->pg, pgp, i)
-                       vector_foreach_slot (pgp->paths, pp, j)
-                               pathinfo(pp, conf->hwtable, DI_PRIO);
+       if (refresh) {
+               vector_foreach_slot (mpp->pg, pgp, i) {
+                       vector_foreach_slot (pgp->paths, pp, j) {
+                               conf = get_multipath_config();
+                               pathinfo(pp, conf, DI_PRIO);
+                               put_multipath_config(conf);
+                       }
+               }
+       }
+
+       if (!mpp->pg || VECTOR_SIZE(mpp->paths) == 0)
+               return 0;
 
        mpp->bestpg = select_path_group(mpp);
 
@@ -132,10 +277,14 @@ coalesce_maps(struct vectors *vecs, vector nmpv)
 {
        struct multipath * ompp;
        vector ompv = vecs->mpvec;
-       unsigned int i;
-       int j;
+       unsigned int i, reassign_maps;
+       struct config *conf;
 
+       conf = get_multipath_config();
+       reassign_maps = conf->reassign_maps;
+       put_multipath_config(conf);
        vector_foreach_slot (ompv, ompp, i) {
+               condlog(3, "%s: coalesce map", ompp->alias);
                if (!find_mp_by_wwid(nmpv, ompp->wwid)) {
                        /*
                         * remove all current maps not allowed by the
@@ -147,22 +296,23 @@ coalesce_maps(struct vectors *vecs, vector nmpv)
                                /*
                                 * may be just because the device is open
                                 */
+                               if (setup_multipath(vecs, ompp) != 0) {
+                                       i--;
+                                       continue;
+                               }
                                if (!vector_alloc_slot(nmpv))
                                        return 1;
 
                                vector_set_slot(nmpv, ompp);
-                               setup_multipath(vecs, ompp);
-
-                               if ((j = find_slot(ompv, (void *)ompp)) != -1)
-                                       vector_del_slot(ompv, j);
 
-                               continue;
+                               vector_del_slot(ompv, i);
+                               i--;
                        }
                        else {
                                dm_lib_release();
                                condlog(2, "%s devmap removed", ompp->alias);
                        }
-               } else if (conf->reassign_maps) {
+               } else if (reassign_maps) {
                        condlog(3, "%s: Reassign existing device-mapper"
                                " devices", ompp->alias);
                        dm_reassign(ompp->alias);
@@ -183,8 +333,9 @@ sync_map_state(struct multipath *mpp)
 
        vector_foreach_slot (mpp->pg, pgp, i){
                vector_foreach_slot (pgp->paths, pp, j){
-                       if (pp->state == PATH_UNCHECKED || 
-                           pp->state == PATH_WILD)
+                       if (pp->state == PATH_UNCHECKED ||
+                           pp->state == PATH_WILD ||
+                           pp->state == PATH_DELAYED)
                                continue;
                        if ((pp->dmstate == PSTATE_FAILED ||
                             pp->dmstate == PSTATE_UNDEF) &&
@@ -210,23 +361,34 @@ sync_maps_state(vector mpvec)
 }
 
 static int
-flush_map(struct multipath * mpp, struct vectors * vecs)
+flush_map(struct multipath * mpp, struct vectors * vecs, int nopaths)
 {
+       int r;
+
+       if (nopaths)
+               r = dm_flush_map_nopaths(mpp->alias, mpp->deferred_remove);
+       else
+               r = dm_flush_map(mpp->alias);
        /*
         * clear references to this map before flushing so we can ignore
         * the spurious uevent we may generate with the dm_flush_map call below
         */
-       if (dm_flush_map(mpp->alias)) {
+       if (r) {
                /*
                 * May not really be an error -- if the map was already flushed
                 * from the device mapper by dmsetup(8) for instance.
                 */
-               condlog(0, "%s: can't flush", mpp->alias);
-               return 1;
+               if (r == 1)
+                       condlog(0, "%s: can't flush", mpp->alias);
+               else {
+                       condlog(2, "%s: devmap deferred remove", mpp->alias);
+                       mpp->deferred_remove = DEFERRED_REMOVE_IN_PROGRESS;
+               }
+               return r;
        }
        else {
                dm_lib_release();
-               condlog(2, "%s: devmap removed", mpp->alias);
+               condlog(2, "%s: map flushed", mpp->alias);
        }
 
        orphan_paths(vecs->pathvec, mpp);
@@ -235,6 +397,47 @@ flush_map(struct multipath * mpp, struct vectors * vecs)
        return 0;
 }
 
+int
+update_map (struct multipath *mpp, struct vectors *vecs)
+{
+       int retries = 3;
+       char params[PARAMS_SIZE] = {0};
+
+retry:
+       condlog(4, "%s: updating new map", mpp->alias);
+       if (adopt_paths(vecs->pathvec, mpp)) {
+               condlog(0, "%s: failed to adopt paths for new map update",
+                       mpp->alias);
+               retries = -1;
+               goto fail;
+       }
+       verify_paths(mpp, vecs);
+       mpp->flush_on_last_del = FLUSH_UNDEF;
+       mpp->action = ACT_RELOAD;
+
+       if (setup_map(mpp, params, PARAMS_SIZE)) {
+               condlog(0, "%s: failed to setup new map in update", mpp->alias);
+               retries = -1;
+               goto fail;
+       }
+       if (domap(mpp, params, 1) <= 0 && retries-- > 0) {
+               condlog(0, "%s: map_udate sleep", mpp->alias);
+               sleep(1);
+               goto retry;
+       }
+       dm_lib_release();
+
+fail:
+       if (setup_multipath(vecs, mpp))
+               return 1;
+
+       sync_map_state(mpp);
+
+       if (retries < 0)
+               condlog(0, "%s: failed reload in new map update", mpp->alias);
+       return 0;
+}
+
 static int
 uev_add_map (struct uevent * uev, struct vectors * vecs)
 {
@@ -254,7 +457,11 @@ uev_add_map (struct uevent * uev, struct vectors * vecs)
                        return 1;
                }
        }
+       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+       lock(&vecs->lock);
+       pthread_testcancel();
        rc = ev_add_map(uev->kernel, alias, vecs);
+       lock_cleanup_pop(vecs->lock);
        FREE(alias);
        return rc;
 }
@@ -265,11 +472,12 @@ ev_add_map (char * dev, char * alias, struct vectors * vecs)
        char * refwwid;
        struct multipath * mpp;
        int map_present;
-       int r = 1;
+       int r = 1, delayed_reconfig, reassign_maps;
+       struct config *conf;
 
        map_present = dm_map_present(alias);
 
-       if (map_present && dm_type(alias, TGT_MPATH) <= 0) {
+       if (map_present && !dm_is_mpath(alias)) {
                condlog(4, "%s: not a multipath map", alias);
                return 0;
        }
@@ -277,12 +485,32 @@ ev_add_map (char * dev, char * alias, struct vectors * vecs)
        mpp = find_mp_by_alias(vecs->mpvec, alias);
 
        if (mpp) {
+               if (mpp->wait_for_udev > 1) {
+                       condlog(2, "%s: performing delayed actions",
+                               mpp->alias);
+                       if (update_map(mpp, vecs))
+                               /* setup multipathd removed the map */
+                               return 1;
+               }
+               conf = get_multipath_config();
+               delayed_reconfig = conf->delayed_reconfig;
+               reassign_maps = conf->reassign_maps;
+               put_multipath_config(conf);
+               if (mpp->wait_for_udev) {
+                       mpp->wait_for_udev = 0;
+                       if (delayed_reconfig &&
+                           !need_to_delay_reconfig(vecs)) {
+                               condlog(2, "reconfigure (delayed)");
+                               set_config_state(DAEMON_CONFIGURE);
+                               return 0;
+                       }
+               }
                /*
                 * Not really an error -- we generate our own uevent
                 * if we create a multipath mapped device as a result
                 * of uev_add_path
                 */
-               if (conf->reassign_maps) {
+               if (reassign_maps) {
                        condlog(3, "%s: Reassign existing device-mapper devices",
                                alias);
                        dm_reassign(alias);
@@ -294,20 +522,28 @@ ev_add_map (char * dev, char * alias, struct vectors * vecs)
        /*
         * now we can register the map
         */
-       if (map_present && (mpp = add_map_without_path(vecs, alias))) {
-               sync_map_state(mpp);
-               condlog(2, "%s: devmap %s registered", alias, dev);
-               return 0;
+       if (map_present) {
+               if ((mpp = add_map_without_path(vecs, alias))) {
+                       sync_map_state(mpp);
+                       condlog(2, "%s: devmap %s registered", alias, dev);
+                       return 0;
+               } else {
+                       condlog(2, "%s: uev_add_map failed", dev);
+                       return 1;
+               }
        }
-       refwwid = get_refwwid(dev, DEV_DEVMAP, vecs->pathvec);
+       r = get_refwwid(CMD_NONE, dev, DEV_DEVMAP, vecs->pathvec, &refwwid);
 
        if (refwwid) {
-               r = coalesce_paths(vecs, NULL, refwwid, 0);
+               r = coalesce_paths(vecs, NULL, refwwid, FORCE_RELOAD_NONE,
+                                  CMD_NONE);
                dm_lib_release();
        }
 
        if (!r)
                condlog(2, "%s: devmap %s added", alias, dev);
+       else if (r == 2)
+               condlog(2, "%s: uev_add_map %s blacklisted", alias, dev);
        else
                condlog(0, "%s: uev_add_map %s failed", alias, dev);
 
@@ -329,6 +565,10 @@ uev_remove_map (struct uevent * uev, struct vectors * vecs)
                return 0;
        }
        minor = uevent_get_minor(uev);
+
+       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+       lock(&vecs->lock);
+       pthread_testcancel();
        mpp = find_mp_by_minor(vecs->mpvec, minor);
 
        if (!mpp) {
@@ -345,10 +585,12 @@ uev_remove_map (struct uevent * uev, struct vectors * vecs)
        orphan_paths(vecs->pathvec, mpp);
        remove_map_and_stop_waiter(mpp, vecs, 1);
 out:
+       lock_cleanup_pop(vecs->lock);
        FREE(alias);
        return 0;
 }
 
+/* Called from CLI handler */
 int
 ev_remove_map (char * devname, char * alias, int minor, struct vectors * vecs)
 {
@@ -359,20 +601,22 @@ ev_remove_map (char * devname, char * alias, int minor, struct vectors * vecs)
        if (!mpp) {
                condlog(2, "%s: devmap not registered, can't remove",
                        devname);
-               return 0;
+               return 1;
        }
        if (strcmp(mpp->alias, alias)) {
                condlog(2, "%s: minor number mismatch (map %d, event %d)",
                        mpp->alias, mpp->dmi->minor, minor);
-               return 0;
+               return 1;
        }
-       return flush_map(mpp, vecs);
+       return flush_map(mpp, vecs, 0);
 }
 
 static int
-uev_add_path (struct uevent *uev, struct vectors * vecs)
+uev_add_path (struct uevent *uev, struct vectors * vecs, int need_do_map)
 {
        struct path *pp;
+       int ret = 0, i;
+       struct config *conf;
 
        condlog(2, "%s: add path (uevent)", uev->kernel);
        if (strstr(uev->kernel, "..") != NULL) {
@@ -383,69 +627,115 @@ uev_add_path (struct uevent *uev, struct vectors * vecs)
                return 1;
        }
 
+       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+       lock(&vecs->lock);
+       pthread_testcancel();
        pp = find_path_by_dev(vecs->pathvec, uev->kernel);
        if (pp) {
+               int r;
+
                condlog(0, "%s: spurious uevent, path already in pathvec",
                        uev->kernel);
-               if (pp->mpp)
-                       return 0;
-       } else {
-               /*
-                * get path vital state
-                */
-               if (!(pp = store_pathinfo(vecs->pathvec, conf->hwtable,
-                                         uev->udev, DI_ALL))) {
-                       condlog(0, "%s: failed to store path info",
-                               uev->kernel);
-                       return 1;
+               if (!pp->mpp && !strlen(pp->wwid)) {
+                       condlog(3, "%s: reinitialize path", uev->kernel);
+                       udev_device_unref(pp->udev);
+                       pp->udev = udev_device_ref(uev->udev);
+                       conf = get_multipath_config();
+                       r = pathinfo(pp, conf,
+                                    DI_ALL | DI_BLACKLIST);
+                       put_multipath_config(conf);
+                       if (r == PATHINFO_OK)
+                               ret = ev_add_path(pp, vecs, need_do_map);
+                       else if (r == PATHINFO_SKIPPED) {
+                               condlog(3, "%s: remove blacklisted path",
+                                       uev->kernel);
+                               i = find_slot(vecs->pathvec, (void *)pp);
+                               if (i != -1)
+                                       vector_del_slot(vecs->pathvec, i);
+                               free_path(pp);
+                       } else {
+                               condlog(0, "%s: failed to reinitialize path",
+                                       uev->kernel);
+                               ret = 1;
+                       }
                }
-               pp->checkint = conf->checkint;
        }
+       lock_cleanup_pop(vecs->lock);
+       if (pp)
+               return ret;
 
-       return (ev_add_path(pp, vecs) != 1)? 0 : 1;
+       /*
+        * get path vital state
+        */
+       conf = get_multipath_config();
+       ret = alloc_path_with_pathinfo(conf, uev->udev,
+                                      uev->wwid, DI_ALL, &pp);
+       put_multipath_config(conf);
+       if (!pp) {
+               if (ret == PATHINFO_SKIPPED)
+                       return 0;
+               condlog(3, "%s: failed to get path info", uev->kernel);
+               return 1;
+       }
+       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+       lock(&vecs->lock);
+       pthread_testcancel();
+       ret = store_path(vecs->pathvec, pp);
+       if (!ret) {
+               conf = get_multipath_config();
+               pp->checkint = conf->checkint;
+               put_multipath_config(conf);
+               ret = ev_add_path(pp, vecs, need_do_map);
+       } else {
+               condlog(0, "%s: failed to store path info, "
+                       "dropping event",
+                       uev->kernel);
+               free_path(pp);
+               ret = 1;
+       }
+       lock_cleanup_pop(vecs->lock);
+       return ret;
 }
 
 /*
  * returns:
  * 0: added
  * 1: error
- * 2: blacklisted
  */
 int
-ev_add_path (struct path * pp, struct vectors * vecs)
+ev_add_path (struct path * pp, struct vectors * vecs, int need_do_map)
 {
        struct multipath * mpp;
-       char empty_buff[WWID_SIZE] = {0};
        char params[PARAMS_SIZE] = {0};
        int retries = 3;
        int start_waiter = 0;
+       int ret;
 
        /*
         * need path UID to go any further
         */
-       if (memcmp(empty_buff, pp->wwid, WWID_SIZE) == 0) {
+       if (strlen(pp->wwid) == 0) {
                condlog(0, "%s: failed to get path uid", pp->dev);
                goto fail; /* leave path added to pathvec */
        }
-       if (filter_path(conf, pp) > 0){
-               int i = find_slot(vecs->pathvec, (void *)pp);
-               if (i != -1)
-                       vector_del_slot(vecs->pathvec, i);
-               free_path(pp);
-               return 2;
+       mpp = find_mp_by_wwid(vecs->mpvec, pp->wwid);
+       if (mpp && mpp->wait_for_udev &&
+           (pathcount(mpp, PATH_UP) > 0 ||
+            (pathcount(mpp, PATH_GHOST) > 0 && pp->tpgs != TPGS_IMPLICIT))) {
+               /* if wait_for_udev is set and valid paths exist */
+               condlog(2, "%s: delaying path addition until %s is fully initialized", pp->dev, mpp->alias);
+               mpp->wait_for_udev = 2;
+               orphan_path(pp, "waiting for create to complete");
+               return 0;
        }
-       mpp = pp->mpp = find_mp_by_wwid(vecs->mpvec, pp->wwid);
+
+       pp->mpp = mpp;
 rescan:
        if (mpp) {
-               if ((!pp->size) || (mpp->size != pp->size)) {
-                       if (!pp->size)
-                               condlog(0, "%s: failed to add new path %s, "
-                                       "device size is 0",
-                                       mpp->alias, pp->dev);
-                       else
-                               condlog(0, "%s: failed to add new path %s, "
-                                       "device size mismatch",
-                                       mpp->alias, pp->dev);
+               if (pp->size && mpp->size != pp->size) {
+                       condlog(0, "%s: failed to add new path %s, "
+                               "device size mismatch",
+                               mpp->alias, pp->dev);
                        int i = find_slot(vecs->pathvec, (void *)pp);
                        if (i != -1)
                                vector_del_slot(vecs->pathvec, i);
@@ -455,24 +745,17 @@ rescan:
 
                condlog(4,"%s: adopting all paths for path %s",
                        mpp->alias, pp->dev);
-               if (adopt_paths(vecs->pathvec, mpp, 1))
+               if (adopt_paths(vecs->pathvec, mpp))
                        goto fail; /* leave path added to pathvec */
 
-               verify_paths(mpp, vecs, NULL);
+               verify_paths(mpp, vecs);
                mpp->flush_on_last_del = FLUSH_UNDEF;
                mpp->action = ACT_RELOAD;
-       }
-       else {
-               if (!pp->size) {
-                       condlog(0, "%s: failed to create new map,"
-                               " device size is 0 ", pp->dev);
-                       int i = find_slot(vecs->pathvec, (void *)pp);
-                       if (i != -1)
-                               vector_del_slot(vecs->pathvec, i);
-                       free_path(pp);
-                       return 1;
+       } else {
+               if (!should_multipath(pp, vecs->pathvec)) {
+                       orphan_path(pp, "only one path");
+                       return 0;
                }
-
                condlog(4,"%s: creating new map", pp->dev);
                if ((mpp = add_map_with_path(vecs, pp, 1))) {
                        mpp->action = ACT_CREATE;
@@ -482,13 +765,20 @@ rescan:
                         */
                        start_waiter = 1;
                }
-               else
+               if (!start_waiter)
                        goto fail; /* leave path added to pathvec */
        }
 
-       /* persistent reseravtion check*/
-       mpath_pr_event_handle(pp);      
+       /* persistent reservation check*/
+       mpath_pr_event_handle(pp);
+
+       if (!need_do_map)
+               return 0;
 
+       if (!dm_map_present(mpp->alias)) {
+               mpp->action = ACT_CREATE;
+               start_waiter = 1;
+       }
        /*
         * push the map to the device-mapper
         */
@@ -500,14 +790,22 @@ rescan:
        /*
         * reload the map for the multipath mapped device
         */
-       if (domap(mpp, params) <= 0) {
+retry:
+       ret = domap(mpp, params, 1);
+       if (ret <= 0) {
+               if (ret < 0 && retries-- > 0) {
+                       condlog(0, "%s: retry domap for addition of new "
+                               "path %s", mpp->alias, pp->dev);
+                       sleep(1);
+                       goto retry;
+               }
                condlog(0, "%s: failed in domap for addition of new "
                        "path %s", mpp->alias, pp->dev);
                /*
                 * deal with asynchronous uevents :((
                 */
                if (mpp->action == ACT_RELOAD && retries-- > 0) {
-                       condlog(0, "%s: uev_add_path sleep", mpp->alias);
+                       condlog(0, "%s: ev_add_path sleep", mpp->alias);
                        sleep(1);
                        update_mpp_paths(mpp, vecs->pathvec);
                        goto rescan;
@@ -533,38 +831,43 @@ rescan:
                        goto fail_map;
 
        if (retries >= 0) {
-               condlog(2, "%s path added to devmap %s", pp->dev, mpp->alias);
+               condlog(2, "%s [%s]: path added to devmap %s",
+                       pp->dev, pp->dev_t, mpp->alias);
                return 0;
-       }
-       else
-               return 1;
+       } else
+               goto fail;
 
 fail_map:
        remove_map(mpp, vecs, 1);
 fail:
-       orphan_path(pp);
+       orphan_path(pp, "failed to add path");
        return 1;
 }
 
 static int
-uev_remove_path (struct uevent *uev, struct vectors * vecs)
+uev_remove_path (struct uevent *uev, struct vectors * vecs, int need_do_map)
 {
        struct path *pp;
+       int ret;
 
        condlog(2, "%s: remove path (uevent)", uev->kernel);
+       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+       lock(&vecs->lock);
+       pthread_testcancel();
        pp = find_path_by_dev(vecs->pathvec, uev->kernel);
-
+       if (pp)
+               ret = ev_remove_path(pp, vecs, need_do_map);
+       lock_cleanup_pop(vecs->lock);
        if (!pp) {
                /* Not an error; path might have been purged earlier */
                condlog(0, "%s: path already removed", uev->kernel);
                return 0;
        }
-
-       return ev_remove_path(pp, vecs);
+       return ret;
 }
 
 int
-ev_remove_path (struct path *pp, struct vectors * vecs)
+ev_remove_path (struct path *pp, struct vectors * vecs, int need_do_map)
 {
        struct multipath * mpp;
        int i, retval = 0;
@@ -601,9 +904,10 @@ ev_remove_path (struct path *pp, struct vectors * vecs)
                                mpp->retry_tick = 0;
                                mpp->no_path_retry = NO_PATH_RETRY_FAIL;
                                mpp->flush_on_last_del = FLUSH_IN_PROGRESS;
+                               mpp->stat_map_failures++;
                                dm_queue_if_no_path(mpp->alias, 0);
                        }
-                       if (!flush_map(mpp, vecs)) {
+                       if (!flush_map(mpp, vecs, 1)) {
                                condlog(2, "%s: removed map after"
                                        " removing all paths",
                                        alias);
@@ -620,11 +924,19 @@ ev_remove_path (struct path *pp, struct vectors * vecs)
                                " removal of path %s", mpp->alias, pp->dev);
                        goto fail;
                }
+
+               if (mpp->wait_for_udev) {
+                       mpp->wait_for_udev = 2;
+                       goto out;
+               }
+
+               if (!need_do_map)
+                       goto out;
                /*
                 * reload the map
                 */
                mpp->action = ACT_RELOAD;
-               if (domap(mpp, params) <= 0) {
+               if (domap(mpp, params, 1) <= 0) {
                        condlog(0, "%s: failed in domap for "
                                "removal of path %s",
                                mpp->alias, pp->dev);
@@ -633,13 +945,12 @@ ev_remove_path (struct path *pp, struct vectors * vecs)
                        /*
                         * update our state from kernel
                         */
-                       if (setup_multipath(vecs, mpp)) {
-                               goto fail;
-                       }
+                       if (setup_multipath(vecs, mpp))
+                               return 1;
                        sync_map_state(mpp);
 
-                       condlog(2, "%s: path removed from map %s",
-                               pp->dev, mpp->alias);
+                       condlog(2, "%s [%s]: path removed from map %s",
+                               pp->dev, pp->dev_t, mpp->alias);
                }
        }
 
@@ -660,28 +971,83 @@ static int
 uev_update_path (struct uevent *uev, struct vectors * vecs)
 {
        int ro, retval = 0;
+       struct path * pp;
+       struct config *conf;
+       int disable_changed_wwids;
+       int needs_reinit = 0;
+
+       conf = get_multipath_config();
+       disable_changed_wwids = conf->disable_changed_wwids;
+       put_multipath_config(conf);
 
        ro = uevent_get_disk_ro(uev);
 
-       if (ro >= 0) {
-               struct path * pp;
+       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+       lock(&vecs->lock);
+       pthread_testcancel();
 
-               condlog(2, "%s: update path write_protect to '%d' (uevent)",
-                       uev->kernel, ro);
-               pp = find_path_by_dev(vecs->pathvec, uev->kernel);
-               if (!pp) {
-                       condlog(0, "%s: spurious uevent, path not found",
-                               uev->kernel);
-                       return 1;
+       pp = find_path_by_dev(vecs->pathvec, uev->kernel);
+       if (pp) {
+               struct multipath *mpp = pp->mpp;
+
+               if (disable_changed_wwids &&
+                   (strlen(pp->wwid) || pp->wwid_changed)) {
+                       char wwid[WWID_SIZE];
+
+                       strcpy(wwid, pp->wwid);
+                       get_uid(pp, pp->state, uev->udev);
+                       if (strcmp(wwid, pp->wwid) != 0) {
+                               condlog(0, "%s: path wwid changed from '%s' to '%s'. disallowing", uev->kernel, wwid, pp->wwid);
+                               strcpy(pp->wwid, wwid);
+                               if (!pp->wwid_changed) {
+                                       pp->wwid_changed = 1;
+                                       pp->tick = 1;
+                                       if (pp->mpp)
+                                               dm_fail_path(pp->mpp->alias, pp->dev_t);
+                               }
+                               goto out;
+                       } else
+                               pp->wwid_changed = 0;
                }
-               if (pp->mpp)
-                       retval = reload_map(vecs, pp->mpp);
 
-               condlog(2, "%s: map %s reloaded (retval %d)",
-                       uev->kernel, pp->mpp->alias, retval);
+               if (pp->initialized == INIT_REQUESTED_UDEV)
+                       needs_reinit = 1;
+               else if (mpp && ro >= 0) {
+                       condlog(2, "%s: update path write_protect to '%d' (uevent)", uev->kernel, ro);
 
+                       if (mpp->wait_for_udev)
+                               mpp->wait_for_udev = 2;
+                       else {
+                               if (ro == 1)
+                                       pp->mpp->force_readonly = 1;
+                               retval = reload_map(vecs, mpp, 0, 1);
+                               pp->mpp->force_readonly = 0;
+                               condlog(2, "%s: map %s reloaded (retval %d)",
+                                       uev->kernel, mpp->alias, retval);
+                       }
+               }
        }
+out:
+       lock_cleanup_pop(vecs->lock);
+       if (!pp) {
+               /* If the path is blacklisted, print a debug/non-default verbosity message. */
+               if (uev->udev) {
+                       int flag = DI_SYSFS | DI_WWID;
+
+                       conf = get_multipath_config();
+                       retval = alloc_path_with_pathinfo(conf, uev->udev, uev->wwid, flag, NULL);
+                       put_multipath_config(conf);
+
+                       if (retval == PATHINFO_SKIPPED) {
+                               condlog(3, "%s: spurious uevent, path is blacklisted", uev->kernel);
+                               return 0;
+                       }
+               }
 
+               condlog(0, "%s: spurious uevent, path not found", uev->kernel);
+       }
+       if (needs_reinit)
+               retval = uev_add_path(uev, vecs, 1);
        return retval;
 }
 
@@ -696,13 +1062,14 @@ map_discovery (struct vectors * vecs)
 
        vector_foreach_slot (vecs->mpvec, mpp, i)
                if (setup_multipath(vecs, mpp))
-                       return 1;
+                       i--;
 
        return 0;
 }
 
 int
-uxsock_trigger (char * str, char ** reply, int * len, void * trigger_data)
+uxsock_trigger (char * str, char ** reply, int * len, bool is_root,
+               void * trigger_data)
 {
        struct vectors * vecs;
        int r;
@@ -711,64 +1078,55 @@ uxsock_trigger (char * str, char ** reply, int * len, void * trigger_data)
        *len = 0;
        vecs = (struct vectors *)trigger_data;
 
-       pthread_cleanup_push(cleanup_lock, &vecs->lock);
-       lock(vecs->lock);
-       pthread_testcancel();
+       if ((str != NULL) && (is_root == false) &&
+           (strncmp(str, "list", strlen("list")) != 0) &&
+           (strncmp(str, "show", strlen("show")) != 0)) {
+               *reply = STRDUP("permission deny: need to be root");
+               if (*reply)
+                       *len = strlen(*reply) + 1;
+               return 1;
+       }
 
-       r = parse_cmd(str, reply, len, vecs);
+       r = parse_cmd(str, reply, len, vecs, uxsock_timeout);
 
        if (r > 0) {
-               *reply = STRDUP("fail\n");
-               *len = strlen(*reply) + 1;
+               if (r == ETIMEDOUT)
+                       *reply = STRDUP("timeout\n");
+               else
+                       *reply = STRDUP("fail\n");
+               if (*reply)
+                       *len = strlen(*reply) + 1;
                r = 1;
        }
        else if (!r && *len == 0) {
                *reply = STRDUP("ok\n");
-               *len = strlen(*reply) + 1;
+               if (*reply)
+                       *len = strlen(*reply) + 1;
                r = 0;
        }
        /* else if (r < 0) leave *reply alone */
 
-       lock_cleanup_pop(vecs->lock);
        return r;
 }
 
-static int
-uev_discard(char * devpath)
-{
-       char *tmp;
-       char a[11], b[11];
-
-       /*
-        * keep only block devices, discard partitions
-        */
-       tmp = strstr(devpath, "/block/");
-       if (tmp == NULL){
-               condlog(4, "no /block/ in '%s'", devpath);
-               return 1;
-       }
-       if (sscanf(tmp, "/block/%10s", a) != 1 ||
-           sscanf(tmp, "/block/%10[^/]/%10s", a, b) == 2) {
-               condlog(4, "discard event on %s", devpath);
-               return 1;
-       }
-       return 0;
-}
-
 int
 uev_trigger (struct uevent * uev, void * trigger_data)
 {
        int r = 0;
        struct vectors * vecs;
+       struct uevent *merge_uev, *tmp;
 
        vecs = (struct vectors *)trigger_data;
 
-       if (uev_discard(uev->devpath))
-               return 0;
+       pthread_cleanup_push(config_cleanup, NULL);
+       pthread_mutex_lock(&config_lock);
+       if (running_state != DAEMON_IDLE &&
+           running_state != DAEMON_RUNNING)
+               pthread_cond_wait(&config_cond, &config_lock);
+       pthread_cleanup_pop(1);
 
-       pthread_cleanup_push(cleanup_lock, &vecs->lock);
-       lock(vecs->lock);
-       pthread_testcancel();
+       if (running_state == DAEMON_SHUTDOWN)
+               return 0;
 
        /*
         * device map event
@@ -788,83 +1146,93 @@ uev_trigger (struct uevent * uev, void * trigger_data)
        }
 
        /*
-        * path add/remove event
+        * path add/remove/change event, add/remove maybe merged
         */
-       if (filter_devnode(conf->blist_devnode, conf->elist_devnode,
-                          uev->kernel) > 0)
-               goto out;
-
-       if (!strncmp(uev->action, "add", 3)) {
-               r = uev_add_path(uev, vecs);
-               goto out;
-       }
-       if (!strncmp(uev->action, "remove", 6)) {
-               r = uev_remove_path(uev, vecs);
-               goto out;
-       }
-       if (!strncmp(uev->action, "change", 6)) {
-               r = uev_update_path(uev, vecs);
-               goto out;
+       list_for_each_entry_safe(merge_uev, tmp, &uev->merge_node, node) {
+               if (!strncmp(merge_uev->action, "add", 3))
+                       r += uev_add_path(merge_uev, vecs, 0);
+               if (!strncmp(merge_uev->action, "remove", 6))
+                       r += uev_remove_path(merge_uev, vecs, 0);
        }
 
+       if (!strncmp(uev->action, "add", 3))
+               r += uev_add_path(uev, vecs, 1);
+       if (!strncmp(uev->action, "remove", 6))
+               r += uev_remove_path(uev, vecs, 1);
+       if (!strncmp(uev->action, "change", 6))
+               r += uev_update_path(uev, vecs);
+
 out:
-       lock_cleanup_pop(vecs->lock);
        return r;
 }
 
+static void rcu_unregister(void *param)
+{
+       rcu_unregister_thread();
+}
+
 static void *
 ueventloop (void * ap)
 {
-       block_signal(SIGUSR1, NULL);
-       block_signal(SIGHUP, NULL);
+       struct udev *udev = ap;
 
-       if (uevent_listen())
+       pthread_cleanup_push(rcu_unregister, NULL);
+       rcu_register_thread();
+       if (uevent_listen(udev))
                condlog(0, "error starting uevent listener");
-
+       pthread_cleanup_pop(1);
        return NULL;
 }
 
 static void *
 uevqloop (void * ap)
 {
-       block_signal(SIGUSR1, NULL);
-       block_signal(SIGHUP, NULL);
-
+       pthread_cleanup_push(rcu_unregister, NULL);
+       rcu_register_thread();
        if (uevent_dispatch(&uev_trigger, ap))
                condlog(0, "error starting uevent dispatcher");
-
+       pthread_cleanup_pop(1);
        return NULL;
 }
 static void *
 uxlsnrloop (void * ap)
 {
-       block_signal(SIGUSR1, NULL);
-       block_signal(SIGHUP, NULL);
-
-       if (cli_init())
+       if (cli_init()) {
+               condlog(1, "Failed to init uxsock listener");
                return NULL;
-
+       }
+       pthread_cleanup_push(rcu_unregister, NULL);
+       rcu_register_thread();
        set_handler_callback(LIST+PATHS, cli_list_paths);
        set_handler_callback(LIST+PATHS+FMT, cli_list_paths_fmt);
+       set_handler_callback(LIST+PATHS+RAW+FMT, cli_list_paths_raw);
+       set_handler_callback(LIST+PATH, cli_list_path);
        set_handler_callback(LIST+MAPS, cli_list_maps);
-       set_handler_callback(LIST+STATUS, cli_list_status);
-       set_handler_callback(LIST+DAEMON, cli_list_daemon);
+       set_unlocked_handler_callback(LIST+STATUS, cli_list_status);
+       set_unlocked_handler_callback(LIST+DAEMON, cli_list_daemon);
        set_handler_callback(LIST+MAPS+STATUS, cli_list_maps_status);
        set_handler_callback(LIST+MAPS+STATS, cli_list_maps_stats);
        set_handler_callback(LIST+MAPS+FMT, cli_list_maps_fmt);
+       set_handler_callback(LIST+MAPS+RAW+FMT, cli_list_maps_raw);
        set_handler_callback(LIST+MAPS+TOPOLOGY, cli_list_maps_topology);
        set_handler_callback(LIST+TOPOLOGY, cli_list_maps_topology);
+       set_handler_callback(LIST+MAPS+JSON, cli_list_maps_json);
        set_handler_callback(LIST+MAP+TOPOLOGY, cli_list_map_topology);
+       set_handler_callback(LIST+MAP+FMT, cli_list_map_fmt);
+       set_handler_callback(LIST+MAP+RAW+FMT, cli_list_map_fmt);
+       set_handler_callback(LIST+MAP+JSON, cli_list_map_json);
        set_handler_callback(LIST+CONFIG, cli_list_config);
        set_handler_callback(LIST+BLACKLIST, cli_list_blacklist);
        set_handler_callback(LIST+DEVICES, cli_list_devices);
        set_handler_callback(LIST+WILDCARDS, cli_list_wildcards);
+       set_handler_callback(RESET+MAPS+STATS, cli_reset_maps_stats);
+       set_handler_callback(RESET+MAP+STATS, cli_reset_map_stats);
        set_handler_callback(ADD+PATH, cli_add_path);
        set_handler_callback(DEL+PATH, cli_del_path);
        set_handler_callback(ADD+MAP, cli_add_map);
        set_handler_callback(DEL+MAP, cli_del_map);
        set_handler_callback(SWITCH+MAP+GROUP, cli_switch_group);
-       set_handler_callback(RECONFIGURE, cli_reconfigure);
+       set_unlocked_handler_callback(RECONFIGURE, cli_reconfigure);
        set_handler_callback(SUSPEND+MAP, cli_suspend);
        set_handler_callback(RESUME+MAP, cli_resume);
        set_handler_callback(RESIZE+MAP, cli_resize);
@@ -876,50 +1244,24 @@ uxlsnrloop (void * ap)
        set_handler_callback(RESTOREQ+MAP, cli_restore_queueing);
        set_handler_callback(DISABLEQ+MAPS, cli_disable_all_queueing);
        set_handler_callback(RESTOREQ+MAPS, cli_restore_all_queueing);
-       set_handler_callback(QUIT, cli_quit);
-       set_handler_callback(SHUTDOWN, cli_shutdown);
+       set_unlocked_handler_callback(QUIT, cli_quit);
+       set_unlocked_handler_callback(SHUTDOWN, cli_shutdown);
        set_handler_callback(GETPRSTATUS+MAP, cli_getprstatus);
        set_handler_callback(SETPRSTATUS+MAP, cli_setprstatus);
        set_handler_callback(UNSETPRSTATUS+MAP, cli_unsetprstatus);
+       set_handler_callback(FORCEQ+DAEMON, cli_force_no_daemon_q);
+       set_handler_callback(RESTOREQ+DAEMON, cli_restore_no_daemon_q);
 
        umask(077);
        uxsock_listen(&uxsock_trigger, ap);
-
+       pthread_cleanup_pop(1);
        return NULL;
 }
 
-int
-exit_daemon (int status)
-{
-       if (status != 0)
-               fprintf(stderr, "bad exit status. see daemon.log\n");
-
-       condlog(3, "unlink pidfile");
-       unlink(DEFAULT_PIDFILE);
-
-       pthread_mutex_lock(&exit_mutex);
-       pthread_cond_signal(&exit_cond);
-       pthread_mutex_unlock(&exit_mutex);
-
-       return status;
-}
-
-const char *
-daemon_status(void)
+void
+exit_daemon (void)
 {
-       switch (running_state) {
-       case DAEMON_INIT:
-               return "init";
-       case DAEMON_START:
-               return "startup";
-       case DAEMON_CONFIGURE:
-               return "configure";
-       case DAEMON_RUNNING:
-               return "running";
-       case DAEMON_SHUTDOWN:
-               return "shutdown";
-       }
-       return NULL;
+       post_config_state(DAEMON_SHUTDOWN);
 }
 
 static void
@@ -939,19 +1281,23 @@ fail_path (struct path * pp, int del_active)
 /*
  * caller must have locked the path list before calling that function
  */
-static void
+static int
 reinstate_path (struct path * pp, int add_active)
 {
+       int ret = 0;
+
        if (!pp->mpp)
-               return;
+               return 0;
 
-       if (dm_reinstate_path(pp->mpp->alias, pp->dev_t))
+       if (dm_reinstate_path(pp->mpp->alias, pp->dev_t)) {
                condlog(0, "%s: reinstate failed", pp->dev_t);
-       else {
+               ret = 1;
+       } else {
                condlog(2, "%s: reinstated", pp->dev_t);
                if (add_active)
                        update_queue_mode_add_path(pp->mpp);
        }
+       return ret;
 }
 
 static void
@@ -995,6 +1341,63 @@ mpvec_garbage_collector (struct vectors * vecs)
        }
 }
 
+/* This is called after a path has started working again. It the multipath
+ * device for this path uses the followover failback type, and this is the
+ * best pathgroup, and this is the first path in the pathgroup to come back
+ * up, then switch to this pathgroup */
+static int
+followover_should_failback(struct path * pp)
+{
+       struct pathgroup * pgp;
+       struct path *pp1;
+       int i;
+
+       if (pp->mpp->pgfailback != -FAILBACK_FOLLOWOVER ||
+           !pp->mpp->pg || !pp->pgindex ||
+           pp->pgindex != pp->mpp->bestpg)
+               return 0;
+
+       pgp = VECTOR_SLOT(pp->mpp->pg, pp->pgindex - 1);
+       vector_foreach_slot(pgp->paths, pp1, i) {
+               if (pp1 == pp)
+                       continue;
+               if (pp1->chkrstate != PATH_DOWN && pp1->chkrstate != PATH_SHAKY)
+                       return 0;
+       }
+       return 1;
+}
+
+static void
+missing_uev_wait_tick(struct vectors *vecs)
+{
+       struct multipath * mpp;
+       unsigned int i;
+       int timed_out = 0, delayed_reconfig;
+       struct config *conf;
+
+       vector_foreach_slot (vecs->mpvec, mpp, i) {
+               if (mpp->wait_for_udev && --mpp->uev_wait_tick <= 0) {
+                       timed_out = 1;
+                       condlog(0, "%s: timeout waiting on creation uevent. enabling reloads", mpp->alias);
+                       if (mpp->wait_for_udev > 1 && update_map(mpp, vecs)) {
+                               /* update_map removed map */
+                               i--;
+                               continue;
+                       }
+                       mpp->wait_for_udev = 0;
+               }
+       }
+
+       conf = get_multipath_config();
+       delayed_reconfig = conf->delayed_reconfig;
+       put_multipath_config(conf);
+       if (timed_out && delayed_reconfig &&
+           !need_to_delay_reconfig(vecs)) {
+               condlog(2, "reconfigure (delayed)");
+               set_config_state(DAEMON_CONFIGURE);
+       }
+}
+
 static void
 defered_failback_tick (vector mpvec)
 {
@@ -1021,10 +1424,11 @@ retry_count_tick(vector mpvec)
        unsigned int i;
 
        vector_foreach_slot (mpvec, mpp, i) {
-               if (mpp->retry_tick) {
+               if (mpp->retry_tick > 0) {
                        mpp->stat_total_queueing_time++;
                        condlog(4, "%s: Retrying.. No active path", mpp->alias);
                        if(--mpp->retry_tick == 0) {
+                               mpp->stat_map_failures++;
                                dm_queue_if_no_path(mpp->alias, 0);
                                condlog(2, "%s: Disable queueing", mpp->alias);
                        }
@@ -1038,12 +1442,15 @@ int update_prio(struct path *pp, int refresh_all)
        struct path *pp1;
        struct pathgroup * pgp;
        int i, j, changed = 0;
+       struct config *conf;
 
        if (refresh_all) {
                vector_foreach_slot (pp->mpp->pg, pgp, i) {
                        vector_foreach_slot (pgp->paths, pp1, j) {
                                oldpriority = pp1->priority;
-                               pathinfo(pp1, conf->hwtable, DI_PRIO);
+                               conf = get_multipath_config();
+                               pathinfo(pp1, conf, DI_PRIO);
+                               put_multipath_config(conf);
                                if (pp1->priority != oldpriority)
                                        changed = 1;
                        }
@@ -1051,68 +1458,207 @@ int update_prio(struct path *pp, int refresh_all)
                return changed;
        }
        oldpriority = pp->priority;
-       pathinfo(pp, conf->hwtable, DI_PRIO);
+       conf = get_multipath_config();
+       if (pp->state != PATH_DOWN)
+               pathinfo(pp, conf, DI_PRIO);
+       put_multipath_config(conf);
+
+       if (pp->priority == oldpriority)
+               return 0;
+       return 1;
+}
+
+int update_path_groups(struct multipath *mpp, struct vectors *vecs, int refresh)
+{
+       if (reload_map(vecs, mpp, refresh, 1))
+               return 1;
+
+       dm_lib_release();
+       if (setup_multipath(vecs, mpp) != 0)
+               return 1;
+       sync_map_state(mpp);
+
+       return 0;
+}
+
+void repair_path(struct path * pp)
+{
+       if (pp->state != PATH_DOWN)
+               return;
+
+       checker_repair(&pp->checker);
+       LOG_MSG(1, checker_message(&pp->checker));
+}
+
+static int check_path_reinstate_state(struct path * pp) {
+       struct timespec curr_time;
+       if (!((pp->mpp->san_path_err_threshold > 0) &&
+                               (pp->mpp->san_path_err_forget_rate > 0) &&
+                               (pp->mpp->san_path_err_recovery_time >0))) {
+               return 0;
+       }
+
+       if (pp->disable_reinstate) {
+               /* If we don't know how much time has passed, automatically
+                * reinstate the path, just to be safe. Also, if there are
+                * no other usable paths, reinstate the path
+                */
+               if (clock_gettime(CLOCK_MONOTONIC, &curr_time) != 0 ||
+                               pp->mpp->nr_active == 0) {
+                       condlog(2, "%s : reinstating path early", pp->dev);
+                       goto reinstate_path;
+               }
+               if ((curr_time.tv_sec - pp->dis_reinstate_time ) > pp->mpp->san_path_err_recovery_time) {
+                       condlog(2,"%s : reinstate the path after err recovery time", pp->dev);
+                       goto reinstate_path;
+               }
+               return 1;
+       }
+       /* forget errors on a working path */
+       if ((pp->state == PATH_UP || pp->state == PATH_GHOST) &&
+                       pp->path_failures > 0) {
+               if (pp->san_path_err_forget_rate > 0){
+                       pp->san_path_err_forget_rate--;
+               } else {
+                       /* for every san_path_err_forget_rate number of
+                        * successful path checks decrement path_failures by 1
+                        */
+                       pp->path_failures--;
+                       pp->san_path_err_forget_rate = pp->mpp->san_path_err_forget_rate;
+               }
+               return 0;
+       }
 
-       if (pp->priority == oldpriority)
+       /* If the path isn't recovering from a failed state, do nothing */
+       if (pp->state != PATH_DOWN && pp->state != PATH_SHAKY &&
+                       pp->state != PATH_TIMEOUT)
                return 0;
-       return 1;
-}
 
-int update_path_groups(struct multipath *mpp, struct vectors *vecs, int refresh)
-{
-       int i;
-       struct path * pp;
-       char params[PARAMS_SIZE];
+       if (pp->path_failures == 0)
+               pp->san_path_err_forget_rate = pp->mpp->san_path_err_forget_rate;
 
-       update_mpp_paths(mpp, vecs->pathvec);
-       if (refresh) {
-               vector_foreach_slot (mpp->paths, pp, i)
-                       pathinfo(pp, conf->hwtable, DI_PRIO);
-       }
-       params[0] = '\0';
-       if (setup_map(mpp, params, PARAMS_SIZE))
-               return 1;
+       pp->path_failures++;
 
-       mpp->action = ACT_RELOAD;
-       if (domap(mpp, params) <= 0) {
-               condlog(0, "%s: failed to update map : %s", mpp->alias,
-                       strerror(errno));
+       /* if we don't know the currently time, we don't know how long to
+        * delay the path, so there's no point in checking if we should
+        */
+
+       if (clock_gettime(CLOCK_MONOTONIC, &curr_time) != 0)
+               return 0;
+       /* when path failures has exceeded the san_path_err_threshold
+        * place the path in delayed state till san_path_err_recovery_time
+        * so that the cutomer can rectify the issue within this time. After
+        * the completion of san_path_err_recovery_time it should
+        * automatically reinstate the path
+        */
+       if (pp->path_failures > pp->mpp->san_path_err_threshold) {
+               condlog(2, "%s : hit error threshold. Delaying path reinstatement", pp->dev);
+               pp->dis_reinstate_time = curr_time.tv_sec;
+               pp->disable_reinstate = 1;
                return 1;
+       } else {
+               return 0;
        }
-       dm_lib_release();
-       if (setup_multipath(vecs, mpp) != 0)
-               return 1;
-       sync_map_state(mpp);
 
+reinstate_path:
+       pp->path_failures = 0;
+       pp->disable_reinstate = 0;
+       pp->san_path_err_forget_rate = 0;
        return 0;
 }
 
-void
-check_path (struct vectors * vecs, struct path * pp)
+/*
+ * Returns '1' if the path has been checked, '-1' if it was blacklisted
+ * and '0' otherwise
+ */
+int
+check_path (struct vectors * vecs, struct path * pp, int ticks)
 {
        int newstate;
        int new_path_up = 0;
+       int chkr_new_path_up = 0;
+       int add_active;
+       int disable_reinstate = 0;
+       int oldchkrstate = pp->chkrstate;
+       int retrigger_tries, checkint;
+       struct config *conf;
+       int ret;
+
+       if ((pp->initialized == INIT_OK ||
+            pp->initialized == INIT_REQUESTED_UDEV) && !pp->mpp)
+               return 0;
 
-       if (!pp->mpp)
-               return;
-
-       if (pp->tick && --pp->tick)
-               return; /* don't check this path yet */
+       if (pp->tick)
+               pp->tick -= (pp->tick > ticks) ? ticks : pp->tick;
+       if (pp->tick)
+               return 0; /* don't check this path yet */
+
+       conf = get_multipath_config();
+       retrigger_tries = conf->retrigger_tries;
+       checkint = conf->checkint;
+       put_multipath_config(conf);
+       if (!pp->mpp && pp->initialized == INIT_MISSING_UDEV &&
+           pp->retriggers < retrigger_tries) {
+               condlog(2, "%s: triggering change event to reinitialize",
+                       pp->dev);
+               pp->initialized = INIT_REQUESTED_UDEV;
+               pp->retriggers++;
+               sysfs_attr_set_value(pp->udev, "uevent", "change",
+                                    strlen("change"));
+               return 0;
+       }
 
        /*
         * provision a next check soonest,
         * in case we exit abnormaly from here
         */
-       pp->tick = conf->checkint;
+       pp->tick = checkint;
 
        newstate = path_offline(pp);
-       if (newstate == PATH_UP)
-               newstate = get_state(pp, 1);
+       /*
+        * Wait for uevent for removed paths;
+        * some LLDDs like zfcp keep paths unavailable
+        * without sending uevents.
+        */
+       if (newstate == PATH_REMOVED)
+               newstate = PATH_DOWN;
+
+       if (newstate == PATH_UP) {
+               conf = get_multipath_config();
+               newstate = get_state(pp, conf, 1);
+               put_multipath_config(conf);
+       } else
+               checker_clear_message(&pp->checker);
+
+       if (pp->wwid_changed) {
+               condlog(2, "%s: path wwid has changed. Refusing to use",
+                       pp->dev);
+               newstate = PATH_DOWN;
+       }
 
        if (newstate == PATH_WILD || newstate == PATH_UNCHECKED) {
                condlog(2, "%s: unusable path", pp->dev);
-               pathinfo(pp, conf->hwtable, 0);
-               return;
+               conf = get_multipath_config();
+               pathinfo(pp, conf, 0);
+               put_multipath_config(conf);
+               return 1;
+       }
+       if (!pp->mpp) {
+               if (!strlen(pp->wwid) && pp->initialized != INIT_MISSING_UDEV &&
+                   (newstate == PATH_UP || newstate == PATH_GHOST)) {
+                       condlog(2, "%s: add missing path", pp->dev);
+                       conf = get_multipath_config();
+                       ret = pathinfo(pp, conf, DI_ALL | DI_BLACKLIST);
+                       if (ret == PATHINFO_OK) {
+                               ev_add_path(pp, vecs, 1);
+                               pp->tick = 1;
+                       } else if (ret == PATHINFO_SKIPPED) {
+                               put_multipath_config(conf);
+                               return -1;
+                       }
+                       put_multipath_config(conf);
+               }
+               return 0;
        }
        /*
         * Async IO in flight. Keep the previous path state
@@ -1120,35 +1666,74 @@ check_path (struct vectors * vecs, struct path * pp)
         */
        if (newstate == PATH_PENDING) {
                pp->tick = 1;
-               return;
+               return 0;
        }
        /*
         * Synchronize with kernel state
         */
-       if (update_multipath_strings(pp->mpp, vecs->pathvec)) {
-               condlog(1, "%s: Could not synchronize with kernel state\n",
+       if (update_multipath_strings(pp->mpp, vecs->pathvec, 1)) {
+               condlog(1, "%s: Could not synchronize with kernel state",
                        pp->dev);
                pp->dmstate = PSTATE_UNDEF;
        }
+       /* if update_multipath_strings orphaned the path, quit early */
+       if (!pp->mpp)
+               return 0;
+
+       if ((newstate == PATH_UP || newstate == PATH_GHOST) &&
+                       check_path_reinstate_state(pp)) {
+               pp->state = PATH_DELAYED;
+               return 1;
+       }
+
+       if ((newstate == PATH_UP || newstate == PATH_GHOST) &&
+            pp->wait_checks > 0) {
+               if (pp->mpp->nr_active > 0) {
+                       pp->state = PATH_DELAYED;
+                       pp->wait_checks--;
+                       return 1;
+               } else
+                       pp->wait_checks = 0;
+       }
+
+       /*
+        * don't reinstate failed path, if its in stand-by
+        * and if target supports only implicit tpgs mode.
+        * this will prevent unnecessary i/o by dm on stand-by
+        * paths if there are no other active paths in map.
+        */
+       disable_reinstate = (newstate == PATH_GHOST &&
+                           pp->mpp->nr_active == 0 &&
+                           pp->tpgs == TPGS_IMPLICIT) ? 1 : 0;
+
+       pp->chkrstate = newstate;
        if (newstate != pp->state) {
                int oldstate = pp->state;
                pp->state = newstate;
+
                LOG_MSG(1, checker_message(&pp->checker));
 
                /*
                 * upon state change, reset the checkint
                 * to the shortest delay
                 */
+               conf = get_multipath_config();
                pp->checkint = conf->checkint;
+               put_multipath_config(conf);
 
-               if (newstate == PATH_DOWN || newstate == PATH_SHAKY) {
+               if (newstate != PATH_UP && newstate != PATH_GHOST) {
                        /*
                         * proactively fail path in the DM
                         */
                        if (oldstate == PATH_UP ||
-                           oldstate == PATH_GHOST)
+                           oldstate == PATH_GHOST) {
                                fail_path(pp, 1);
-                       else
+                               if (pp->mpp->delay_wait_checks > 0 &&
+                                   pp->watch_checks > 0) {
+                                       pp->wait_checks = pp->mpp->delay_wait_checks;
+                                       pp->watch_checks = 0;
+                               }
+                       }else
                                fail_path(pp, 0);
 
                        /*
@@ -1157,7 +1742,8 @@ check_path (struct vectors * vecs, struct path * pp)
                        pp->mpp->failback_tick = 0;
 
                        pp->mpp->stat_path_failures++;
-                       return;
+                       repair_path(pp);
+                       return 1;
                }
 
                if(newstate == PATH_UP || newstate == PATH_GHOST){
@@ -1175,13 +1761,26 @@ check_path (struct vectors * vecs, struct path * pp)
                 * reinstate this path
                 */
                if (oldstate != PATH_UP &&
-                   oldstate != PATH_GHOST)
-                       reinstate_path(pp, 1);
-               else
-                       reinstate_path(pp, 0);
-
+                   oldstate != PATH_GHOST) {
+                       if (pp->mpp->delay_watch_checks > 0)
+                               pp->watch_checks = pp->mpp->delay_watch_checks;
+                       add_active = 1;
+               } else {
+                       if (pp->watch_checks > 0)
+                               pp->watch_checks--;
+                       add_active = 0;
+               }
+               if (!disable_reinstate && reinstate_path(pp, add_active)) {
+                       condlog(3, "%s: reload map", pp->dev);
+                       ev_add_path(pp, vecs, 1);
+                       pp->tick = 1;
+                       return 0;
+               }
                new_path_up = 1;
 
+               if (oldchkrstate != PATH_UP && oldchkrstate != PATH_GHOST)
+                       chkr_new_path_up = 1;
+
                /*
                 * if at least one path is up in a group, and
                 * the group is disabled, re-enable it
@@ -1190,35 +1789,57 @@ check_path (struct vectors * vecs, struct path * pp)
                        enable_group(pp);
        }
        else if (newstate == PATH_UP || newstate == PATH_GHOST) {
-               if (pp->dmstate == PSTATE_FAILED ||
-                   pp->dmstate == PSTATE_UNDEF) {
+               if ((pp->dmstate == PSTATE_FAILED ||
+                   pp->dmstate == PSTATE_UNDEF) &&
+                   !disable_reinstate) {
                        /* Clear IO errors */
-                       reinstate_path(pp, 0);
+                       if (reinstate_path(pp, 0)) {
+                               condlog(3, "%s: reload map", pp->dev);
+                               ev_add_path(pp, vecs, 1);
+                               pp->tick = 1;
+                               return 0;
+                       }
                } else {
+                       unsigned int max_checkint;
                        LOG_MSG(4, checker_message(&pp->checker));
-                       /*
-                        * double the next check delay.
-                        * max at conf->max_checkint
-                        */
-                       if (pp->checkint < (conf->max_checkint / 2))
-                               pp->checkint = 2 * pp->checkint;
-                       else
-                               pp->checkint = conf->max_checkint;
+                       conf = get_multipath_config();
+                       max_checkint = conf->max_checkint;
+                       put_multipath_config(conf);
+                       if (pp->checkint != max_checkint) {
+                               /*
+                                * double the next check delay.
+                                * max at conf->max_checkint
+                                */
+                               if (pp->checkint < (max_checkint / 2))
+                                       pp->checkint = 2 * pp->checkint;
+                               else
+                                       pp->checkint = max_checkint;
 
+                               condlog(4, "%s: delay next check %is",
+                                       pp->dev_t, pp->checkint);
+                       }
+                       if (pp->watch_checks > 0)
+                               pp->watch_checks--;
                        pp->tick = pp->checkint;
-                       condlog(4, "%s: delay next check %is",
-                               pp->dev_t, pp->tick);
                }
        }
        else if (newstate == PATH_DOWN) {
-               if (conf->log_checker_err == LOG_CHKR_ERR_ONCE)
+               int log_checker_err;
+
+               conf = get_multipath_config();
+               log_checker_err = conf->log_checker_err;
+               put_multipath_config(conf);
+               if (log_checker_err == LOG_CHKR_ERR_ONCE)
                        LOG_MSG(3, checker_message(&pp->checker));
                else
                        LOG_MSG(2, checker_message(&pp->checker));
        }
 
        pp->state = newstate;
+       repair_path(pp);
 
+       if (pp->mpp->wait_for_udev)
+               return 1;
        /*
         * path prio refreshing
         */
@@ -1233,9 +1854,24 @@ check_path (struct vectors * vecs, struct path * pp)
                    (new_path_up || pp->mpp->failback_tick <= 0))
                        pp->mpp->failback_tick =
                                pp->mpp->pgfailback + 1;
-               else if (pp->mpp->pgfailback == -FAILBACK_IMMEDIATE)
+               else if (pp->mpp->pgfailback == -FAILBACK_IMMEDIATE ||
+                        (chkr_new_path_up && followover_should_failback(pp)))
                        switch_pathgroup(pp->mpp);
        }
+       return 1;
+}
+
+static void init_path_check_interval(struct vectors *vecs)
+{
+       struct config *conf;
+       struct path *pp;
+       unsigned int i;
+
+       vector_foreach_slot (vecs->pathvec, pp, i) {
+               conf = get_multipath_config();
+               pp->checkint = conf->checkint;
+               put_multipath_config(conf);
+       }
 }
 
 static void *
@@ -1245,47 +1881,140 @@ checkerloop (void *ap)
        struct path *pp;
        int count = 0;
        unsigned int i;
-       sigset_t old;
+       struct itimerval timer_tick_it;
+       struct timespec last_time;
+       struct config *conf;
 
+       pthread_cleanup_push(rcu_unregister, NULL);
+       rcu_register_thread();
        mlockall(MCL_CURRENT | MCL_FUTURE);
        vecs = (struct vectors *)ap;
        condlog(2, "path checkers start up");
 
-       /*
-        * init the path check interval
-        */
-       vector_foreach_slot (vecs->pathvec, pp, i) {
-               pp->checkint = conf->checkint;
-       }
+       /* Tweak start time for initial path check */
+       if (clock_gettime(CLOCK_MONOTONIC, &last_time) != 0)
+               last_time.tv_sec = 0;
+       else
+               last_time.tv_sec -= 1;
 
        while (1) {
-               block_signal(SIGHUP, &old);
+               struct timespec diff_time, start_time, end_time;
+               int num_paths = 0, ticks = 0, signo, strict_timing, rc = 0;
+               sigset_t mask;
+
+               if (clock_gettime(CLOCK_MONOTONIC, &start_time) != 0)
+                       start_time.tv_sec = 0;
+               if (start_time.tv_sec && last_time.tv_sec) {
+                       timespecsub(&start_time, &last_time, &diff_time);
+                       condlog(4, "tick (%lu.%06lu secs)",
+                               diff_time.tv_sec, diff_time.tv_nsec / 1000);
+                       last_time = start_time;
+                       ticks = diff_time.tv_sec;
+               } else {
+                       ticks = 1;
+                       condlog(4, "tick (%d ticks)", ticks);
+               }
+#ifdef USE_SYSTEMD
+               if (use_watchdog)
+                       sd_notify(0, "WATCHDOG=1");
+#endif
+               rc = set_config_state(DAEMON_RUNNING);
+               if (rc == ETIMEDOUT) {
+                       condlog(4, "timeout waiting for DAEMON_IDLE");
+                       continue;
+               }
+
                pthread_cleanup_push(cleanup_lock, &vecs->lock);
-               lock(vecs->lock);
+               lock(&vecs->lock);
                pthread_testcancel();
-               condlog(4, "tick");
-
-               if (vecs->pathvec) {
-                       vector_foreach_slot (vecs->pathvec, pp, i) {
-                               check_path(vecs, pp);
-                       }
-               }
-               if (vecs->mpvec) {
-                       defered_failback_tick(vecs->mpvec);
-                       retry_count_tick(vecs->mpvec);
+               vector_foreach_slot (vecs->pathvec, pp, i) {
+                       rc = check_path(vecs, pp, ticks);
+                       if (rc < 0) {
+                               vector_del_slot(vecs->pathvec, i);
+                               free_path(pp);
+                               i--;
+                       } else
+                               num_paths += rc;
                }
+               lock_cleanup_pop(vecs->lock);
+
+               pthread_cleanup_push(cleanup_lock, &vecs->lock);
+               lock(&vecs->lock);
+               pthread_testcancel();
+               defered_failback_tick(vecs->mpvec);
+               retry_count_tick(vecs->mpvec);
+               missing_uev_wait_tick(vecs);
+               lock_cleanup_pop(vecs->lock);
+
                if (count)
                        count--;
                else {
+                       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+                       lock(&vecs->lock);
+                       pthread_testcancel();
                        condlog(4, "map garbage collection");
                        mpvec_garbage_collector(vecs);
                        count = MAPGCINT;
+                       lock_cleanup_pop(vecs->lock);
                }
 
-               lock_cleanup_pop(vecs->lock);
-               pthread_sigmask(SIG_SETMASK, &old, NULL);
-               sleep(1);
+               diff_time.tv_nsec = 0;
+               if (start_time.tv_sec &&
+                   clock_gettime(CLOCK_MONOTONIC, &end_time) == 0) {
+                       timespecsub(&end_time, &start_time, &diff_time);
+                       if (num_paths) {
+                               unsigned int max_checkint;
+
+                               condlog(3, "checked %d path%s in %lu.%06lu secs",
+                                       num_paths, num_paths > 1 ? "s" : "",
+                                       diff_time.tv_sec,
+                                       diff_time.tv_nsec / 1000);
+                               conf = get_multipath_config();
+                               max_checkint = conf->max_checkint;
+                               put_multipath_config(conf);
+                               if (diff_time.tv_sec > max_checkint)
+                                       condlog(1, "path checkers took longer "
+                                               "than %lu seconds, consider "
+                                               "increasing max_polling_interval",
+                                               diff_time.tv_sec);
+                       }
+               }
+
+               post_config_state(DAEMON_IDLE);
+               conf = get_multipath_config();
+               strict_timing = conf->strict_timing;
+               put_multipath_config(conf);
+               if (!strict_timing)
+                       sleep(1);
+               else {
+                       timer_tick_it.it_interval.tv_sec = 0;
+                       timer_tick_it.it_interval.tv_usec = 0;
+                       if (diff_time.tv_nsec) {
+                               timer_tick_it.it_value.tv_sec = 0;
+                               timer_tick_it.it_value.tv_usec =
+                                    1000UL * 1000 * 1000 - diff_time.tv_nsec;
+                       } else {
+                               timer_tick_it.it_value.tv_sec = 1;
+                               timer_tick_it.it_value.tv_usec = 0;
+                       }
+                       setitimer(ITIMER_REAL, &timer_tick_it, NULL);
+
+                       sigemptyset(&mask);
+                       sigaddset(&mask, SIGALRM);
+                       condlog(3, "waiting for %lu.%06lu secs",
+                               timer_tick_it.it_value.tv_sec,
+                               timer_tick_it.it_value.tv_usec);
+                       if (sigwait(&mask, &signo) != 0) {
+                               condlog(3, "sigwait failed with error %d",
+                                       errno);
+                               conf = get_multipath_config();
+                               conf->strict_timing = 0;
+                               put_multipath_config(conf);
+                               break;
+                       }
+               }
        }
+       pthread_cleanup_pop(1);
        return NULL;
 }
 
@@ -1295,23 +2024,36 @@ configure (struct vectors * vecs, int start_waiters)
        struct multipath * mpp;
        struct path * pp;
        vector mpvec;
-       int i;
+       int i, ret;
+       struct config *conf;
+       static int force_reload = FORCE_RELOAD_WEAK;
 
-       if (!vecs->pathvec && !(vecs->pathvec = vector_alloc()))
+       if (!vecs->pathvec && !(vecs->pathvec = vector_alloc())) {
+               condlog(0, "couldn't allocate path vec in configure");
                return 1;
+       }
 
-       if (!vecs->mpvec && !(vecs->mpvec = vector_alloc()))
+       if (!vecs->mpvec && !(vecs->mpvec = vector_alloc())) {
+               condlog(0, "couldn't allocate multipath vec in configure");
                return 1;
+       }
 
-       if (!(mpvec = vector_alloc()))
+       if (!(mpvec = vector_alloc())) {
+               condlog(0, "couldn't allocate new maps vec in configure");
                return 1;
+       }
 
        /*
         * probe for current path (from sysfs) and map (from dm) sets
         */
-       path_discovery(vecs->pathvec, conf, DI_ALL);
+       ret = path_discovery(vecs->pathvec, DI_ALL);
+       if (ret < 0) {
+               condlog(0, "configure failed at path discovery");
+               return 1;
+       }
 
        vector_foreach_slot (vecs->pathvec, pp, i){
+               conf = get_multipath_config();
                if (filter_path(conf, pp) > 0){
                        vector_del_slot(vecs->pathvec, i);
                        free_path(pp);
@@ -1319,27 +2061,41 @@ configure (struct vectors * vecs, int start_waiters)
                }
                else
                        pp->checkint = conf->checkint;
+               put_multipath_config(conf);
        }
-       if (map_discovery(vecs))
+       if (map_discovery(vecs)) {
+               condlog(0, "configure failed at map discovery");
                return 1;
+       }
 
        /*
         * create new set of maps & push changed ones into dm
+        * In the first call, use FORCE_RELOAD_WEAK to avoid making
+        * superfluous ACT_RELOAD ioctls. Later calls are done
+        * with FORCE_RELOAD_YES.
         */
-       if (coalesce_paths(vecs, mpvec, NULL, 1))
+       ret = coalesce_paths(vecs, mpvec, NULL, force_reload, CMD_NONE);
+       if (force_reload == FORCE_RELOAD_WEAK)
+               force_reload = FORCE_RELOAD_YES;
+       if (ret) {
+               condlog(0, "configure failed while coalescing paths");
                return 1;
+       }
 
        /*
         * may need to remove some maps which are no longer relevant
         * e.g., due to blacklist changes in conf file
         */
-       if (coalesce_maps(vecs, mpvec))
+       if (coalesce_maps(vecs, mpvec)) {
+               condlog(0, "configure failed while coalescing maps");
                return 1;
+       }
 
        dm_lib_release();
 
        sync_maps_state(mpvec);
        vector_foreach_slot(mpvec, mpp, i){
+               remember_wwid(mpp->wwid);
                update_map_pr(mpp);
        }
 
@@ -1358,20 +2114,51 @@ configure (struct vectors * vecs, int start_waiters)
         * start dm event waiter threads for these new maps
         */
        vector_foreach_slot(vecs->mpvec, mpp, i) {
-               if (setup_multipath(vecs, mpp))
+               if (setup_multipath(vecs, mpp)) {
+                       i--;
+                       continue;
+               }
+               if (start_waiters) {
+                       if (start_waiter_thread(mpp, vecs)) {
+                               remove_map(mpp, vecs, 1);
+                               i--;
+                       }
+               }
+       }
+       return 0;
+}
+
+int
+need_to_delay_reconfig(struct vectors * vecs)
+{
+       struct multipath *mpp;
+       int i;
+
+       if (!VECTOR_SIZE(vecs->mpvec))
+               return 0;
+
+       vector_foreach_slot(vecs->mpvec, mpp, i) {
+               if (mpp->wait_for_udev)
                        return 1;
-               if (start_waiters)
-                       if (start_waiter_thread(mpp, vecs))
-                               return 1;
        }
        return 0;
 }
 
+void rcu_free_config(struct rcu_head *head)
+{
+       struct config *conf = container_of(head, struct config, rcu);
+
+       free_config(conf);
+}
+
 int
 reconfigure (struct vectors * vecs)
 {
-       struct config * old = conf;
-       int retval = 1;
+       struct config * old, *conf;
+
+       conf = load_config(DEFAULT_CONFIGFILE);
+       if (!conf)
+               return 1;
 
        /*
         * free old map and path vectors ... they use old conf state
@@ -1379,21 +2166,33 @@ reconfigure (struct vectors * vecs)
        if (VECTOR_SIZE(vecs->mpvec))
                remove_maps_and_stop_waiters(vecs);
 
-       if (VECTOR_SIZE(vecs->pathvec))
-               free_pathvec(vecs->pathvec, FREE_PATHS);
-
+       free_pathvec(vecs->pathvec, FREE_PATHS);
        vecs->pathvec = NULL;
-       conf = NULL;
 
-       if (!load_config(DEFAULT_CONFIGFILE)) {
-               conf->verbosity = old->verbosity;
-               conf->daemon = 1;
-               configure(vecs, 1);
-               free_config(old);
-               retval = 0;
+       /* Re-read any timezone changes */
+       tzset();
+
+       dm_drv_version(conf->version, TGT_MPATH);
+       if (verbosity)
+               conf->verbosity = verbosity;
+       if (bindings_read_only)
+               conf->bindings_read_only = bindings_read_only;
+       if (conf->find_multipaths) {
+               condlog(2, "find_multipaths is set: -n is implied");
+               ignore_new_devs = 1;
        }
+       if (ignore_new_devs)
+               conf->ignore_new_devs = ignore_new_devs;
+       uxsock_timeout = conf->uxsock_timeout;
 
-       return retval;
+       old = rcu_dereference(multipath_conf);
+       rcu_assign_pointer(multipath_conf, conf);
+       call_rcu(&old->rcu, rcu_free_config);
+
+       configure(vecs, 1);
+
+
+       return 0;
 }
 
 static struct vectors *
@@ -1406,21 +2205,9 @@ init_vecs (void)
        if (!vecs)
                return NULL;
 
-       vecs->lock.mutex =
-               (pthread_mutex_t *)MALLOC(sizeof(pthread_mutex_t));
-
-       if (!vecs->lock.mutex)
-               goto out;
-
-       pthread_mutex_init(vecs->lock.mutex, NULL);
-       vecs->lock.depth = 0;
+       pthread_mutex_init(&vecs->lock.mutex, NULL);
 
        return vecs;
-
-out:
-       FREE(vecs);
-       condlog(0, "failed to init paths");
-       return NULL;
 }
 
 static void *
@@ -1442,43 +2229,67 @@ signal_set(int signo, void (*func) (int))
                return (osig.sa_handler);
 }
 
+void
+handle_signals(void)
+{
+       if (exit_sig) {
+               condlog(2, "exit (signal)");
+               exit_daemon();
+       }
+       if (reconfig_sig) {
+               condlog(2, "reconfigure (signal)");
+               set_config_state(DAEMON_CONFIGURE);
+       }
+       if (log_reset_sig) {
+               condlog(2, "reset log (signal)");
+               pthread_mutex_lock(&logq_lock);
+               log_reset("multipathd");
+               pthread_mutex_unlock(&logq_lock);
+       }
+       exit_sig = 0;
+       reconfig_sig = 0;
+       log_reset_sig = 0;
+}
+
 static void
 sighup (int sig)
 {
-       condlog(2, "reconfigure (SIGHUP)");
-
-       if (running_state != DAEMON_RUNNING)
-               return;
-
-       lock(gvecs->lock);
-       reconfigure(gvecs);
-       unlock(gvecs->lock);
-
-#ifdef _DEBUG_
-       dbg_free_final(NULL);
-#endif
+       reconfig_sig = 1;
 }
 
 static void
 sigend (int sig)
 {
-       exit_daemon(0);
+       exit_sig = 1;
 }
 
 static void
 sigusr1 (int sig)
 {
-       condlog(3, "SIGUSR1 received");
+       log_reset_sig = 1;
+}
+
+static void
+sigusr2 (int sig)
+{
+       condlog(3, "SIGUSR2 received");
 }
 
 static void
 signal_init(void)
 {
+       sigset_t set;
+
+       sigemptyset(&set);
+       sigaddset(&set, SIGUSR2);
+       pthread_sigmask(SIG_SETMASK, &set, NULL);
+
        signal_set(SIGHUP, sighup);
        signal_set(SIGUSR1, sigusr1);
+       signal_set(SIGUSR2, sigusr2);
        signal_set(SIGINT, sigend);
        signal_set(SIGTERM, sigend);
-       signal(SIGPIPE, SIG_IGN);
+       signal_set(SIGPIPE, sigend);
 }
 
 static void
@@ -1510,7 +2321,13 @@ set_oom_adj (void)
 #endif
        FILE *fp;
        struct stat st;
+       char *envp;
 
+       envp = getenv("OOMScoreAdjust");
+       if (envp) {
+               condlog(3, "Using systemd provided OOMScoreAdjust");
+               return;
+       }
        do {
                if (stat(file, &st) == 0){
                        fp = fopen(file, "w");
@@ -1528,8 +2345,12 @@ set_oom_adj (void)
                                strerror(errno));
                        return;
                }
+#ifdef OOM_ADJUST_MIN
                file = "/proc/self/oom_adj";
                score = OOM_ADJUST_MIN;
+#else
+               retry = 0;
+#endif
        } while (retry--);
        condlog(0, "couldn't adjust oom score");
 }
@@ -1538,47 +2359,79 @@ static int
 child (void * param)
 {
        pthread_t check_thr, uevent_thr, uxlsnr_thr, uevq_thr;
-       pthread_attr_t log_attr, misc_attr;
+       pthread_attr_t log_attr, misc_attr, uevent_attr;
        struct vectors * vecs;
        struct multipath * mpp;
        int i;
+#ifdef USE_SYSTEMD
+       unsigned long checkint;
+       int startup_done = 0;
+#endif
        int rc;
+       int pid_fd = -1;
+       struct config *conf;
+       char *envp;
 
        mlockall(MCL_CURRENT | MCL_FUTURE);
+       signal_init();
+       rcu_init();
 
-       setup_thread_attr(&misc_attr, 64 * 1024, 1);
+       setup_thread_attr(&misc_attr, 64 * 1024, 0);
+       setup_thread_attr(&uevent_attr, DEFAULT_UEVENT_STACKSIZE * 1024, 0);
        setup_thread_attr(&waiter_attr, 32 * 1024, 1);
 
-       if (logsink) {
+       if (logsink == 1) {
                setup_thread_attr(&log_attr, 64 * 1024, 0);
                log_thread_start(&log_attr);
                pthread_attr_destroy(&log_attr);
        }
+       pid_fd = pidfile_create(DEFAULT_PIDFILE, daemon_pid);
+       if (pid_fd < 0) {
+               condlog(1, "failed to create pidfile");
+               if (logsink == 1)
+                       log_thread_stop();
+               exit(1);
+       }
 
-       running_state = DAEMON_START;
+       post_config_state(DAEMON_START);
 
        condlog(2, "--------start up--------");
        condlog(2, "read " DEFAULT_CONFIGFILE);
 
-       if (load_config(DEFAULT_CONFIGFILE))
-               exit(1);
-
-       if (init_checkers()) {
+       conf = load_config(DEFAULT_CONFIGFILE);
+       if (!conf)
+               goto failed;
+
+       if (verbosity)
+               conf->verbosity = verbosity;
+       if (bindings_read_only)
+               conf->bindings_read_only = bindings_read_only;
+       if (ignore_new_devs)
+               conf->ignore_new_devs = ignore_new_devs;
+       uxsock_timeout = conf->uxsock_timeout;
+       rcu_assign_pointer(multipath_conf, conf);
+       dm_init(conf->verbosity);
+       dm_drv_version(conf->version, TGT_MPATH);
+       if (init_checkers(conf->multipath_dir)) {
                condlog(0, "failed to initialize checkers");
-               exit(1);
+               goto failed;
        }
-       if (init_prio()) {
+       if (init_prio(conf->multipath_dir)) {
                condlog(0, "failed to initialize prioritizers");
-               exit(1);
+               goto failed;
        }
 
        setlogmask(LOG_UPTO(conf->verbosity + 3));
 
-       if (conf->max_fds) {
+       envp = getenv("LimitNOFILE");
+
+       if (envp) {
+               condlog(2,"Using systemd provided open fds limit of %s", envp);
+       } else if (conf->max_fds) {
                struct rlimit fd_limit;
 
                if (getrlimit(RLIMIT_NOFILE, &fd_limit) < 0) {
-                       condlog(0, "can't get open fds limit: %s\n",
+                       condlog(0, "can't get open fds limit: %s",
                                strerror(errno));
                        fd_limit.rlim_cur = 0;
                        fd_limit.rlim_max = 0;
@@ -1589,103 +2442,133 @@ child (void * param)
                                fd_limit.rlim_max = conf->max_fds;
                        if (setrlimit(RLIMIT_NOFILE, &fd_limit) < 0) {
                                condlog(0, "can't set open fds limit to "
-                                       "%lu/%lu : %s\n",
+                                       "%lu/%lu : %s",
                                        fd_limit.rlim_cur, fd_limit.rlim_max,
                                        strerror(errno));
                        } else {
-                               condlog(3, "set open fds limit to %lu/%lu\n",
+                               condlog(3, "set open fds limit to %lu/%lu",
                                        fd_limit.rlim_cur, fd_limit.rlim_max);
                        }
                }
 
        }
 
-       signal_init();
+       vecs = gvecs = init_vecs();
+       if (!vecs)
+               goto failed;
+
        setscheduler();
        set_oom_adj();
-       vecs = gvecs = init_vecs();
 
-       if (!vecs)
-               exit(1);
+       dm_udev_set_sync_support(0);
+#ifdef USE_SYSTEMD
+       envp = getenv("WATCHDOG_USEC");
+       if (envp && sscanf(envp, "%lu", &checkint) == 1) {
+               /* Value is in microseconds */
+               conf->max_checkint = checkint / 1000000;
+               /* Rescale checkint */
+               if (conf->checkint > conf->max_checkint)
+                       conf->checkint = conf->max_checkint;
+               else
+                       conf->checkint = conf->max_checkint / 4;
+               condlog(3, "enabling watchdog, interval %d max %d",
+                       conf->checkint, conf->max_checkint);
+               use_watchdog = conf->checkint;
+       }
+#endif
+       /*
+        * Startup done, invalidate configuration
+        */
+       conf = NULL;
+
+       /*
+        * Signal start of configuration
+        */
+       post_config_state(DAEMON_CONFIGURE);
+
+       init_path_check_interval(vecs);
 
-       conf->daemon = 1;
-       udev_set_sync_support(0);
        /*
         * Start uevent listener early to catch events
         */
-       if ((rc = pthread_create(&uevent_thr, &misc_attr, ueventloop, vecs))) {
+       if ((rc = pthread_create(&uevent_thr, &uevent_attr, ueventloop, udev))) {
                condlog(0, "failed to create uevent thread: %d", rc);
-               exit(1);
+               goto failed;
        }
+       pthread_attr_destroy(&uevent_attr);
        if ((rc = pthread_create(&uxlsnr_thr, &misc_attr, uxlsnrloop, vecs))) {
                condlog(0, "failed to create cli listener: %d", rc);
-               exit(1);
-       }
-       /*
-        * fetch and configure both paths and multipaths
-        */
-       lock(vecs->lock);
-       running_state = DAEMON_CONFIGURE;
-
-       if (configure(vecs, 1)) {
-               unlock(vecs->lock);
-               condlog(0, "failure during configuration");
-               exit(1);
+               goto failed;
        }
-       unlock(vecs->lock);
 
        /*
         * start threads
         */
        if ((rc = pthread_create(&check_thr, &misc_attr, checkerloop, vecs))) {
                condlog(0,"failed to create checker loop thread: %d", rc);
-               exit(1);
+               goto failed;
        }
        if ((rc = pthread_create(&uevq_thr, &misc_attr, uevqloop, vecs))) {
                condlog(0, "failed to create uevent dispatcher: %d", rc);
-               exit(1);
+               goto failed;
        }
        pthread_attr_destroy(&misc_attr);
 
-       pthread_mutex_lock(&exit_mutex);
-       /* Startup complete, create logfile */
-       if (pidfile_create(DEFAULT_PIDFILE, daemon_pid))
-               /* Ignore errors, we can live without */
-               condlog(1, "failed to create pidfile");
-
-       running_state = DAEMON_RUNNING;
-       pthread_cond_wait(&exit_cond, &exit_mutex);
+       while (running_state != DAEMON_SHUTDOWN) {
+               pthread_cleanup_push(config_cleanup, NULL);
+               pthread_mutex_lock(&config_lock);
+               if (running_state != DAEMON_CONFIGURE &&
+                   running_state != DAEMON_SHUTDOWN) {
+                       pthread_cond_wait(&config_cond, &config_lock);
+               }
+               pthread_cleanup_pop(1);
+               if (running_state == DAEMON_CONFIGURE) {
+                       pthread_cleanup_push(cleanup_lock, &vecs->lock);
+                       lock(&vecs->lock);
+                       pthread_testcancel();
+                       if (!need_to_delay_reconfig(vecs)) {
+                               reconfigure(vecs);
+                       } else {
+                               conf = get_multipath_config();
+                               conf->delayed_reconfig = 1;
+                               put_multipath_config(conf);
+                       }
+                       lock_cleanup_pop(vecs->lock);
+                       post_config_state(DAEMON_IDLE);
+#ifdef USE_SYSTEMD
+                       if (!startup_done) {
+                               sd_notify(0, "READY=1");
+                               startup_done = 1;
+                       }
+#endif
+               }
+       }
 
-       /*
-        * exit path
-        */
-       running_state = DAEMON_SHUTDOWN;
-       block_signal(SIGHUP, NULL);
-       lock(vecs->lock);
+       lock(&vecs->lock);
+       conf = get_multipath_config();
        if (conf->queue_without_daemon == QUE_NO_DAEMON_OFF)
                vector_foreach_slot(vecs->mpvec, mpp, i)
                        dm_queue_if_no_path(mpp->alias, 0);
+       put_multipath_config(conf);
        remove_maps_and_stop_waiters(vecs);
-       unlock(vecs->lock);
+       unlock(&vecs->lock);
 
        pthread_cancel(check_thr);
        pthread_cancel(uevent_thr);
        pthread_cancel(uxlsnr_thr);
        pthread_cancel(uevq_thr);
 
-       lock(vecs->lock);
+       pthread_join(check_thr, NULL);
+       pthread_join(uevent_thr, NULL);
+       pthread_join(uxlsnr_thr, NULL);
+       pthread_join(uevq_thr, NULL);
+
+       lock(&vecs->lock);
        free_pathvec(vecs->pathvec, FREE_PATHS);
        vecs->pathvec = NULL;
-       unlock(vecs->lock);
-       /* Now all the waitevent threads will start rushing in. */
-       while (vecs->lock.depth > 0) {
-               sleep (1); /* This is weak. */
-               condlog(3,"Have %d wait event checkers threads to de-alloc, waiting..\n", vecs->lock.depth);
-       }
-       pthread_mutex_destroy(vecs->lock.mutex);
-       FREE(vecs->lock.mutex);
-       vecs->lock.depth = 0;
-       vecs->lock.mutex = NULL;
+       unlock(&vecs->lock);
+
+       pthread_mutex_destroy(&vecs->lock.mutex);
        FREE(vecs);
        vecs = NULL;
 
@@ -1701,7 +2584,7 @@ child (void * param)
 
        condlog(2, "--------shut down-------");
 
-       if (logsink)
+       if (logsink == 1)
                log_thread_stop();
 
        /*
@@ -1709,14 +2592,28 @@ child (void * param)
         * because logging functions like dlog() and dm_write_log()
         * reference the config.
         */
-       free_config(conf);
-       conf = NULL;
-
+       conf = rcu_dereference(multipath_conf);
+       rcu_assign_pointer(multipath_conf, NULL);
+       call_rcu(&conf->rcu, rcu_free_config);
+       udev_unref(udev);
+       udev = NULL;
+       pthread_attr_destroy(&waiter_attr);
 #ifdef _DEBUG_
        dbg_free_final(NULL);
 #endif
 
+#ifdef USE_SYSTEMD
+       sd_notify(0, "ERRNO=0");
+#endif
        exit(0);
+
+failed:
+#ifdef USE_SYSTEMD
+       sd_notify(0, "ERRNO=1");
+#endif
+       if (pid_fd >= 0)
+               close(pid_fd);
+       exit(1);
 }
 
 static int
@@ -1779,10 +2676,17 @@ main (int argc, char *argv[])
        extern int optind;
        int arg;
        int err;
+       int foreground = 0;
+       struct config *conf;
+
+       ANNOTATE_BENIGN_RACE_SIZED(&multipath_conf, sizeof(multipath_conf),
+                                  "Manipulated through RCU");
+       ANNOTATE_BENIGN_RACE_SIZED(&running_state, sizeof(running_state),
+               "Suppress complaints about unprotected running_state reads");
+       ANNOTATE_BENIGN_RACE_SIZED(&uxsock_timeout, sizeof(uxsock_timeout),
+               "Suppress complaints about this scalar variable");
 
        logsink = 1;
-       running_state = DAEMON_INIT;
-       dm_init();
 
        if (getuid() != 0) {
                fprintf(stderr, "need to be root\n");
@@ -1795,15 +2699,16 @@ main (int argc, char *argv[])
                        strerror(errno));
        umask(umask(077) | 022);
 
-       conf = alloc_config();
+       pthread_cond_init_mono(&config_cond);
 
-       if (!conf)
-               exit(1);
+       udev = udev_new();
 
-       while ((arg = getopt(argc, argv, ":dv:k::")) != EOF ) {
-       switch(arg) {
+       while ((arg = getopt(argc, argv, ":dsv:k::Bn")) != EOF ) {
+               switch(arg) {
                case 'd':
-                       logsink = 0;
+                       foreground = 1;
+                       if (logsink > 0)
+                               logsink = 0;
                        //debug=1; /* ### comment me out ### */
                        break;
                case 'v':
@@ -1811,13 +2716,31 @@ main (int argc, char *argv[])
                            !isdigit(optarg[0]))
                                exit(1);
 
-                       conf->verbosity = atoi(optarg);
+                       verbosity = atoi(optarg);
+                       break;
+               case 's':
+                       logsink = -1;
                        break;
                case 'k':
-                       uxclnt(optarg);
+                       conf = load_config(DEFAULT_CONFIGFILE);
+                       if (!conf)
+                               exit(1);
+                       if (verbosity)
+                               conf->verbosity = verbosity;
+                       uxsock_timeout = conf->uxsock_timeout;
+                       uxclnt(optarg, uxsock_timeout + 100);
+                       free_config(conf);
                        exit(0);
+               case 'B':
+                       bindings_read_only = 1;
+                       break;
+               case 'n':
+                       ignore_new_devs = 1;
+                       break;
                default:
-                       ;
+                       fprintf(stderr, "Invalid argument '-%c'\n",
+                               optopt);
+                       exit(1);
                }
        }
        if (optind < argc) {
@@ -1825,6 +2748,13 @@ main (int argc, char *argv[])
                char * s = cmd;
                char * c = s;
 
+               conf = load_config(DEFAULT_CONFIGFILE);
+               if (!conf)
+                       exit(1);
+               if (verbosity)
+                       conf->verbosity = verbosity;
+               uxsock_timeout = conf->uxsock_timeout;
+               memset(cmd, 0x0, CMDSIZE);
                while (optind < argc) {
                        if (strchr(argv[optind], ' '))
                                c += snprintf(c, s + CMDSIZE - c, "\"%s\" ", argv[optind]);
@@ -1833,13 +2763,17 @@ main (int argc, char *argv[])
                        optind++;
                }
                c += snprintf(c, s + CMDSIZE - c, "\n");
-               uxclnt(s);
+               uxclnt(s, uxsock_timeout + 100);
+               free_config(conf);
                exit(0);
        }
 
-       if (!logsink)
+       if (foreground) {
+               if (!isatty(fileno(stdout)))
+                       setbuf(stdout, NULL);
                err = 0;
-       else
+               daemon_pid = getpid();
+       } else
                err = daemonize();
 
        if (err < 0)
@@ -1867,18 +2801,18 @@ void *  mpath_pr_event_handler_fn (void * pathp )
 
        resp = mpath_alloc_prin_response(MPATH_PRIN_RKEY_SA);
        if (!resp){
-               condlog(0,"%s Alloc failed for prin response \n", pp->dev);
+               condlog(0,"%s Alloc failed for prin response", pp->dev);
                return NULL;
        }
 
        ret = prin_do_scsi_ioctl(pp->dev, MPATH_PRIN_RKEY_SA, resp, 0);
        if (ret != MPATH_PR_SUCCESS )
        {
-               condlog(0,"%s : pr in read keys service action failed. Error=%d\n", pp->dev, ret);
+               condlog(0,"%s : pr in read keys service action failed. Error=%d", pp->dev, ret);
                goto out;
        }
 
-       condlog(3, " event pr=%d addlen=%d\n",resp->prin_descriptor.prin_readkeys.prgeneration,
+       condlog(3, " event pr=%d addlen=%d",resp->prin_descriptor.prin_readkeys.prgeneration,
                        resp->prin_descriptor.prin_readkeys.additional_length );
 
        if (resp->prin_descriptor.prin_readkeys.additional_length == 0 )
@@ -1900,7 +2834,7 @@ void *  mpath_pr_event_handler_fn (void * pathp )
        isFound =0;
        for (i = 0; i < resp->prin_descriptor.prin_readkeys.additional_length/8; i++ )
        {
-               condlog(2, "PR IN READKEYS[%d]  reservation key:\n",i);
+               condlog(2, "PR IN READKEYS[%d]  reservation key:",i);
                dumpHex((char *)&resp->prin_descriptor.prin_readkeys.key_list[i*8], 8 , -1);
                if (!memcmp(mpp->reservation_key, &resp->prin_descriptor.prin_readkeys.key_list[i*8], 8))
                {
@@ -1912,7 +2846,7 @@ void *  mpath_pr_event_handler_fn (void * pathp )
        if (!isFound)
        {
                condlog(0, "%s: Either device not registered or ", pp->dev);
-               condlog(0, "host is not authorised for registration. Skip path\n");
+               condlog(0, "host is not authorised for registration. Skip path");
                ret = MPATH_PR_OTHER;
                goto out;
        }
@@ -1926,12 +2860,12 @@ void *  mpath_pr_event_handler_fn (void * pathp )
        }
        param->num_transportid = 0;
 
-       condlog(3, "device %s:%s \n", pp->dev, pp->mpp->wwid);
+       condlog(3, "device %s:%s", pp->dev, pp->mpp->wwid);
 
        ret = prout_do_scsi_ioctl(pp->dev, MPATH_PROUT_REG_IGN_SA, 0, 0, param, 0);
        if (ret != MPATH_PR_SUCCESS )
        {
-               condlog(0,"%s: Reservation registration failed. Error: %d\n", pp->dev, ret);
+               condlog(0,"%s: Reservation registration failed. Error: %d", pp->dev, ret);
        }
        mpp->prflag = 1;
 
@@ -1958,11 +2892,10 @@ int mpath_pr_event_handle(struct path *pp)
 
        rc = pthread_create(&thread, NULL , mpath_pr_event_handler_fn, pp);
        if (rc) {
-               condlog(0, "%s: ERROR; return code from pthread_create() is %d\n", pp->dev, rc);
+               condlog(0, "%s: ERROR; return code from pthread_create() is %d", pp->dev, rc);
                return -1;
        }
        pthread_attr_destroy(&attr);
        rc = pthread_join(thread, NULL);
        return 0;
 }
-