From a29728463b254ce81ecefdf20c1a02e01d9361da Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Thu, 31 Jul 2014 17:41:33 +0200 Subject: drbd: Backport the "events2" command The events2 command originates from drbd-9 development. It features more information but requires a incompatible change in output format. Therefore the previous events command continues to exist, the new improved events2 command becomes available now. This prepares the user-base for a later switch to the complete drbd9 code base. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- drivers/block/drbd/drbd_nl.c | 625 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 622 insertions(+), 3 deletions(-) (limited to 'drivers/block/drbd/drbd_nl.c') diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index d37c509e6a44..aa805cdde769 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -36,6 +36,7 @@ #include "drbd_int.h" #include "drbd_protocol.h" #include "drbd_req.h" +#include "drbd_state_change.h" #include #include #include @@ -75,11 +76,17 @@ int drbd_adm_get_status(struct sk_buff *skb, struct genl_info *info); int drbd_adm_get_timeout_type(struct sk_buff *skb, struct genl_info *info); /* .dumpit */ int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb); +int drbd_adm_get_initial_state(struct sk_buff *skb, struct netlink_callback *cb); #include #include "drbd_nla.h" #include +static atomic_t drbd_genl_seq = ATOMIC_INIT(2); /* two. */ +static atomic_t notify_genl_seq = ATOMIC_INIT(2); /* two. */ + +DEFINE_MUTEX(notification_mutex); + /* used blkdev_get_by_path, to claim our meta data device(s) */ static char *drbd_m_holder = "Hands off! this is DRBD's meta data device."; @@ -349,6 +356,7 @@ int drbd_khelper(struct drbd_device *device, char *cmd) sib.sib_reason = SIB_HELPER_PRE; sib.helper_name = cmd; drbd_bcast_event(device, &sib); + notify_helper(NOTIFY_CALL, device, connection, cmd, 0); ret = call_usermodehelper(usermode_helper, argv, envp, UMH_WAIT_PROC); if (ret) drbd_warn(device, "helper command: %s %s %s exit code %u (0x%x)\n", @@ -361,6 +369,7 @@ int drbd_khelper(struct drbd_device *device, char *cmd) sib.sib_reason = SIB_HELPER_POST; sib.helper_exit_code = ret; drbd_bcast_event(device, &sib); + notify_helper(NOTIFY_RESPONSE, device, connection, cmd, ret); if (current == connection->worker.task) clear_bit(CALLBACK_PENDING, &connection->flags); @@ -388,6 +397,7 @@ static int conn_khelper(struct drbd_connection *connection, char *cmd) drbd_info(connection, "helper command: %s %s %s\n", usermode_helper, cmd, resource_name); /* TODO: conn_bcast_event() ?? */ + notify_helper(NOTIFY_CALL, NULL, connection, cmd, 0); ret = call_usermodehelper(usermode_helper, argv, envp, UMH_WAIT_PROC); if (ret) @@ -399,6 +409,7 @@ static int conn_khelper(struct drbd_connection *connection, char *cmd) usermode_helper, cmd, resource_name, (ret >> 8) & 0xff, ret); /* TODO: conn_bcast_event() ?? */ + notify_helper(NOTIFY_RESPONSE, NULL, connection, cmd, ret); if (ret < 0) /* Ignore any ERRNOs we got. */ ret = 0; @@ -2248,8 +2259,31 @@ int drbd_adm_net_opts(struct sk_buff *skb, struct genl_info *info) return 0; } +static void connection_to_info(struct connection_info *info, + struct drbd_connection *connection) +{ + info->conn_connection_state = connection->cstate; + info->conn_role = conn_highest_peer(connection); +} + +static void peer_device_to_info(struct peer_device_info *info, + struct drbd_peer_device *peer_device) +{ + struct drbd_device *device = peer_device->device; + + info->peer_repl_state = + max_t(enum drbd_conns, C_WF_REPORT_PARAMS, device->state.conn); + info->peer_disk_state = device->state.pdsk; + info->peer_resync_susp_user = device->state.user_isp; + info->peer_resync_susp_peer = device->state.peer_isp; + info->peer_resync_susp_dependency = device->state.aftr_isp; +} + int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info) { + struct connection_info connection_info; + enum drbd_notification_type flags; + unsigned int peer_devices = 0; struct drbd_config_context adm_ctx; struct drbd_peer_device *peer_device; struct net_conf *old_net_conf, *new_net_conf = NULL; @@ -2350,6 +2384,22 @@ int drbd_adm_connect(struct sk_buff *skb, struct genl_info *info) connection->peer_addr_len = nla_len(adm_ctx.peer_addr); memcpy(&connection->peer_addr, nla_data(adm_ctx.peer_addr), connection->peer_addr_len); + idr_for_each_entry(&connection->peer_devices, peer_device, i) { + peer_devices++; + } + + connection_to_info(&connection_info, connection); + flags = (peer_devices--) ? NOTIFY_CONTINUES : 0; + mutex_lock(¬ification_mutex); + notify_connection_state(NULL, 0, connection, &connection_info, NOTIFY_CREATE | flags); + idr_for_each_entry(&connection->peer_devices, peer_device, i) { + struct peer_device_info peer_device_info; + + peer_device_to_info(&peer_device_info, peer_device); + flags = (peer_devices--) ? NOTIFY_CONTINUES : 0; + notify_peer_device_state(NULL, 0, peer_device, &peer_device_info, NOTIFY_CREATE | flags); + } + mutex_unlock(¬ification_mutex); mutex_unlock(&adm_ctx.resource->conf_update); rcu_read_lock(); @@ -2431,6 +2481,8 @@ static enum drbd_state_rv conn_try_disconnect(struct drbd_connection *connection drbd_err(connection, "unexpected rv2=%d in conn_try_disconnect()\n", rv2); + /* Unlike in DRBD 9, the state engine has generated + * NOTIFY_DESTROY events before clearing connection->net_conf. */ } return rv; } @@ -3417,8 +3469,18 @@ drbd_check_resource_name(struct drbd_config_context *adm_ctx) return NO_ERROR; } +static void resource_to_info(struct resource_info *info, + struct drbd_resource *resource) +{ + info->res_role = conn_highest_role(first_connection(resource)); + info->res_susp = resource->susp; + info->res_susp_nod = resource->susp_nod; + info->res_susp_fen = resource->susp_fen; +} + int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info) { + struct drbd_connection *connection; struct drbd_config_context adm_ctx; enum drbd_ret_code retcode; struct res_opts res_opts; @@ -3453,14 +3515,32 @@ int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info) /* not yet safe for genl_family.parallel_ops */ mutex_lock(&resources_mutex); - if (!conn_create(adm_ctx.resource_name, &res_opts)) - retcode = ERR_NOMEM; + connection = conn_create(adm_ctx.resource_name, &res_opts); mutex_unlock(&resources_mutex); + + if (connection) { + struct resource_info resource_info; + + mutex_lock(¬ification_mutex); + resource_to_info(&resource_info, connection->resource); + notify_resource_state(NULL, 0, connection->resource, + &resource_info, NOTIFY_CREATE); + mutex_unlock(¬ification_mutex); + } else + retcode = ERR_NOMEM; + out: drbd_adm_finish(&adm_ctx, info, retcode); return 0; } +static void device_to_info(struct device_info *info, + struct drbd_device *device) +{ + info->dev_disk_state = device->state.disk; +} + + int drbd_adm_new_minor(struct sk_buff *skb, struct genl_info *info) { struct drbd_config_context adm_ctx; @@ -3495,6 +3575,36 @@ int drbd_adm_new_minor(struct sk_buff *skb, struct genl_info *info) mutex_lock(&adm_ctx.resource->adm_mutex); retcode = drbd_create_device(&adm_ctx, dh->minor); + if (retcode == NO_ERROR) { + struct drbd_device *device; + struct drbd_peer_device *peer_device; + struct device_info info; + unsigned int peer_devices = 0; + enum drbd_notification_type flags; + + device = minor_to_device(dh->minor); + for_each_peer_device(peer_device, device) { + if (!has_net_conf(peer_device->connection)) + continue; + peer_devices++; + } + + device_to_info(&info, device); + mutex_lock(¬ification_mutex); + flags = (peer_devices--) ? NOTIFY_CONTINUES : 0; + notify_device_state(NULL, 0, device, &info, NOTIFY_CREATE | flags); + for_each_peer_device(peer_device, device) { + struct peer_device_info peer_device_info; + + if (!has_net_conf(peer_device->connection)) + continue; + peer_device_to_info(&peer_device_info, peer_device); + flags = (peer_devices--) ? NOTIFY_CONTINUES : 0; + notify_peer_device_state(NULL, 0, peer_device, &peer_device_info, + NOTIFY_CREATE | flags); + } + mutex_unlock(¬ification_mutex); + } mutex_unlock(&adm_ctx.resource->adm_mutex); out: drbd_adm_finish(&adm_ctx, info, retcode); @@ -3503,13 +3613,35 @@ out: static enum drbd_ret_code adm_del_minor(struct drbd_device *device) { + struct drbd_peer_device *peer_device; + if (device->state.disk == D_DISKLESS && /* no need to be device->state.conn == C_STANDALONE && * we may want to delete a minor from a live replication group. */ device->state.role == R_SECONDARY) { + struct drbd_connection *connection = + first_connection(device->resource); + _drbd_request_state(device, NS(conn, C_WF_REPORT_PARAMS), CS_VERBOSE + CS_WAIT_COMPLETE); + + /* If the state engine hasn't stopped the sender thread yet, we + * need to flush the sender work queue before generating the + * DESTROY events here. */ + if (get_t_state(&connection->worker) == RUNNING) + drbd_flush_workqueue(&connection->sender_work); + + mutex_lock(¬ification_mutex); + for_each_peer_device(peer_device, device) { + if (!has_net_conf(peer_device->connection)) + continue; + notify_peer_device_state(NULL, 0, peer_device, NULL, + NOTIFY_DESTROY | NOTIFY_CONTINUES); + } + notify_device_state(NULL, 0, device, NULL, NOTIFY_DESTROY); + mutex_unlock(¬ification_mutex); + drbd_delete_device(device); return NO_ERROR; } else @@ -3546,6 +3678,13 @@ static int adm_del_resource(struct drbd_resource *resource) if (!idr_is_empty(&resource->devices)) return ERR_RES_IN_USE; + /* The state engine has stopped the sender thread, so we don't + * need to flush the sender work queue before generating the + * DESTROY event here. */ + mutex_lock(¬ification_mutex); + notify_resource_state(NULL, 0, resource, NULL, NOTIFY_DESTROY); + mutex_unlock(¬ification_mutex); + mutex_lock(&resources_mutex); list_del_rcu(&resource->resources); mutex_unlock(&resources_mutex); @@ -3644,7 +3783,6 @@ finish: void drbd_bcast_event(struct drbd_device *device, const struct sib_info *sib) { - static atomic_t drbd_genl_seq = ATOMIC_INIT(2); /* two. */ struct sk_buff *msg; struct drbd_genlmsghdr *d_out; unsigned seq; @@ -3679,3 +3817,484 @@ failed: "Event seq:%u sib_reason:%u\n", err, seq, sib->sib_reason); } + +static void device_to_statistics(struct device_statistics *s, + struct drbd_device *device) +{ + memset(s, 0, sizeof(*s)); + s->dev_upper_blocked = !may_inc_ap_bio(device); + if (get_ldev(device)) { + struct drbd_md *md = &device->ldev->md; + u64 *history_uuids = (u64 *)s->history_uuids; + struct request_queue *q; + int n; + + spin_lock_irq(&md->uuid_lock); + s->dev_current_uuid = md->uuid[UI_CURRENT]; + BUILD_BUG_ON(sizeof(s->history_uuids) < UI_HISTORY_END - UI_HISTORY_START + 1); + for (n = 0; n < UI_HISTORY_END - UI_HISTORY_START + 1; n++) + history_uuids[n] = md->uuid[UI_HISTORY_START + n]; + for (; n < HISTORY_UUIDS; n++) + history_uuids[n] = 0; + s->history_uuids_len = HISTORY_UUIDS; + spin_unlock_irq(&md->uuid_lock); + + s->dev_disk_flags = md->flags; + q = bdev_get_queue(device->ldev->backing_bdev); + s->dev_lower_blocked = + bdi_congested(&q->backing_dev_info, + (1 << WB_async_congested) | + (1 << WB_sync_congested)); + put_ldev(device); + } + s->dev_size = drbd_get_capacity(device->this_bdev); + s->dev_read = device->read_cnt; + s->dev_write = device->writ_cnt; + s->dev_al_writes = device->al_writ_cnt; + s->dev_bm_writes = device->bm_writ_cnt; + s->dev_upper_pending = atomic_read(&device->ap_bio_cnt); + s->dev_lower_pending = atomic_read(&device->local_cnt); + s->dev_al_suspended = test_bit(AL_SUSPENDED, &device->flags); + s->dev_exposed_data_uuid = device->ed_uuid; +} + +enum mdf_peer_flag { + MDF_PEER_CONNECTED = 1 << 0, + MDF_PEER_OUTDATED = 1 << 1, + MDF_PEER_FENCING = 1 << 2, + MDF_PEER_FULL_SYNC = 1 << 3, +}; + +static void peer_device_to_statistics(struct peer_device_statistics *s, + struct drbd_peer_device *peer_device) +{ + struct drbd_device *device = peer_device->device; + + memset(s, 0, sizeof(*s)); + s->peer_dev_received = device->recv_cnt; + s->peer_dev_sent = device->send_cnt; + s->peer_dev_pending = atomic_read(&device->ap_pending_cnt) + + atomic_read(&device->rs_pending_cnt); + s->peer_dev_unacked = atomic_read(&device->unacked_cnt); + s->peer_dev_out_of_sync = drbd_bm_total_weight(device) << (BM_BLOCK_SHIFT - 9); + s->peer_dev_resync_failed = device->rs_failed << (BM_BLOCK_SHIFT - 9); + if (get_ldev(device)) { + struct drbd_md *md = &device->ldev->md; + + spin_lock_irq(&md->uuid_lock); + s->peer_dev_bitmap_uuid = md->uuid[UI_BITMAP]; + spin_unlock_irq(&md->uuid_lock); + s->peer_dev_flags = + (drbd_md_test_flag(device->ldev, MDF_CONNECTED_IND) ? + MDF_PEER_CONNECTED : 0) + + (drbd_md_test_flag(device->ldev, MDF_CONSISTENT) && + !drbd_md_test_flag(device->ldev, MDF_WAS_UP_TO_DATE) ? + MDF_PEER_OUTDATED : 0) + + /* FIXME: MDF_PEER_FENCING? */ + (drbd_md_test_flag(device->ldev, MDF_FULL_SYNC) ? + MDF_PEER_FULL_SYNC : 0); + put_ldev(device); + } +} + +static int nla_put_notification_header(struct sk_buff *msg, + enum drbd_notification_type type) +{ + struct drbd_notification_header nh = { + .nh_type = type, + }; + + return drbd_notification_header_to_skb(msg, &nh, true); +} + +void notify_resource_state(struct sk_buff *skb, + unsigned int seq, + struct drbd_resource *resource, + struct resource_info *resource_info, + enum drbd_notification_type type) +{ + struct resource_statistics resource_statistics; + struct drbd_genlmsghdr *dh; + bool multicast = false; + int err; + + if (!skb) { + seq = atomic_inc_return(¬ify_genl_seq); + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO); + err = -ENOMEM; + if (!skb) + goto failed; + multicast = true; + } + + err = -EMSGSIZE; + dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_RESOURCE_STATE); + if (!dh) + goto nla_put_failure; + dh->minor = -1U; + dh->ret_code = NO_ERROR; + if (nla_put_drbd_cfg_context(skb, resource, NULL, NULL) || + nla_put_notification_header(skb, type) || + ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY && + resource_info_to_skb(skb, resource_info, true))) + goto nla_put_failure; + resource_statistics.res_stat_write_ordering = resource->write_ordering; + err = resource_statistics_to_skb(skb, &resource_statistics, !capable(CAP_SYS_ADMIN)); + if (err) + goto nla_put_failure; + genlmsg_end(skb, dh); + if (multicast) { + err = drbd_genl_multicast_events(skb, 0); + /* skb has been consumed or freed in netlink_broadcast() */ + if (err && err != -ESRCH) + goto failed; + } + return; + +nla_put_failure: + nlmsg_free(skb); +failed: + drbd_err(resource, "Error %d while broadcasting event. Event seq:%u\n", + err, seq); +} + +void notify_device_state(struct sk_buff *skb, + unsigned int seq, + struct drbd_device *device, + struct device_info *device_info, + enum drbd_notification_type type) +{ + struct device_statistics device_statistics; + struct drbd_genlmsghdr *dh; + bool multicast = false; + int err; + + if (!skb) { + seq = atomic_inc_return(¬ify_genl_seq); + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO); + err = -ENOMEM; + if (!skb) + goto failed; + multicast = true; + } + + err = -EMSGSIZE; + dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_DEVICE_STATE); + if (!dh) + goto nla_put_failure; + dh->minor = device->minor; + dh->ret_code = NO_ERROR; + if (nla_put_drbd_cfg_context(skb, device->resource, NULL, device) || + nla_put_notification_header(skb, type) || + ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY && + device_info_to_skb(skb, device_info, true))) + goto nla_put_failure; + device_to_statistics(&device_statistics, device); + device_statistics_to_skb(skb, &device_statistics, !capable(CAP_SYS_ADMIN)); + genlmsg_end(skb, dh); + if (multicast) { + err = drbd_genl_multicast_events(skb, 0); + /* skb has been consumed or freed in netlink_broadcast() */ + if (err && err != -ESRCH) + goto failed; + } + return; + +nla_put_failure: + nlmsg_free(skb); +failed: + drbd_err(device, "Error %d while broadcasting event. Event seq:%u\n", + err, seq); +} + +void notify_connection_state(struct sk_buff *skb, + unsigned int seq, + struct drbd_connection *connection, + struct connection_info *connection_info, + enum drbd_notification_type type) +{ + struct connection_statistics connection_statistics; + struct drbd_genlmsghdr *dh; + bool multicast = false; + int err; + + if (!skb) { + seq = atomic_inc_return(¬ify_genl_seq); + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO); + err = -ENOMEM; + if (!skb) + goto failed; + multicast = true; + } + + err = -EMSGSIZE; + dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_CONNECTION_STATE); + if (!dh) + goto nla_put_failure; + dh->minor = -1U; + dh->ret_code = NO_ERROR; + if (nla_put_drbd_cfg_context(skb, connection->resource, connection, NULL) || + nla_put_notification_header(skb, type) || + ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY && + connection_info_to_skb(skb, connection_info, true))) + goto nla_put_failure; + connection_statistics.conn_congested = test_bit(NET_CONGESTED, &connection->flags); + connection_statistics_to_skb(skb, &connection_statistics, !capable(CAP_SYS_ADMIN)); + genlmsg_end(skb, dh); + if (multicast) { + err = drbd_genl_multicast_events(skb, 0); + /* skb has been consumed or freed in netlink_broadcast() */ + if (err && err != -ESRCH) + goto failed; + } + return; + +nla_put_failure: + nlmsg_free(skb); +failed: + drbd_err(connection, "Error %d while broadcasting event. Event seq:%u\n", + err, seq); +} + +void notify_peer_device_state(struct sk_buff *skb, + unsigned int seq, + struct drbd_peer_device *peer_device, + struct peer_device_info *peer_device_info, + enum drbd_notification_type type) +{ + struct peer_device_statistics peer_device_statistics; + struct drbd_resource *resource = peer_device->device->resource; + struct drbd_genlmsghdr *dh; + bool multicast = false; + int err; + + if (!skb) { + seq = atomic_inc_return(¬ify_genl_seq); + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO); + err = -ENOMEM; + if (!skb) + goto failed; + multicast = true; + } + + err = -EMSGSIZE; + dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_PEER_DEVICE_STATE); + if (!dh) + goto nla_put_failure; + dh->minor = -1U; + dh->ret_code = NO_ERROR; + if (nla_put_drbd_cfg_context(skb, resource, peer_device->connection, peer_device->device) || + nla_put_notification_header(skb, type) || + ((type & ~NOTIFY_FLAGS) != NOTIFY_DESTROY && + peer_device_info_to_skb(skb, peer_device_info, true))) + goto nla_put_failure; + peer_device_to_statistics(&peer_device_statistics, peer_device); + peer_device_statistics_to_skb(skb, &peer_device_statistics, !capable(CAP_SYS_ADMIN)); + genlmsg_end(skb, dh); + if (multicast) { + err = drbd_genl_multicast_events(skb, 0); + /* skb has been consumed or freed in netlink_broadcast() */ + if (err && err != -ESRCH) + goto failed; + } + return; + +nla_put_failure: + nlmsg_free(skb); +failed: + drbd_err(peer_device, "Error %d while broadcasting event. Event seq:%u\n", + err, seq); +} + +void notify_helper(enum drbd_notification_type type, + struct drbd_device *device, struct drbd_connection *connection, + const char *name, int status) +{ + struct drbd_resource *resource = device ? device->resource : connection->resource; + struct drbd_helper_info helper_info; + unsigned int seq = atomic_inc_return(¬ify_genl_seq); + struct sk_buff *skb = NULL; + struct drbd_genlmsghdr *dh; + int err; + + strlcpy(helper_info.helper_name, name, sizeof(helper_info.helper_name)); + helper_info.helper_name_len = min(strlen(name), sizeof(helper_info.helper_name)); + helper_info.helper_status = status; + + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_NOIO); + err = -ENOMEM; + if (!skb) + goto fail; + + err = -EMSGSIZE; + dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_HELPER); + if (!dh) + goto fail; + dh->minor = device ? device->minor : -1; + dh->ret_code = NO_ERROR; + mutex_lock(¬ification_mutex); + if (nla_put_drbd_cfg_context(skb, resource, connection, device) || + nla_put_notification_header(skb, type) || + drbd_helper_info_to_skb(skb, &helper_info, true)) + goto unlock_fail; + genlmsg_end(skb, dh); + err = drbd_genl_multicast_events(skb, 0); + skb = NULL; + /* skb has been consumed or freed in netlink_broadcast() */ + if (err && err != -ESRCH) + goto unlock_fail; + mutex_unlock(¬ification_mutex); + return; + +unlock_fail: + mutex_unlock(¬ification_mutex); +fail: + nlmsg_free(skb); + drbd_err(resource, "Error %d while broadcasting event. Event seq:%u\n", + err, seq); +} + +static void notify_initial_state_done(struct sk_buff *skb, unsigned int seq) +{ + struct drbd_genlmsghdr *dh; + int err; + + err = -EMSGSIZE; + dh = genlmsg_put(skb, 0, seq, &drbd_genl_family, 0, DRBD_INITIAL_STATE_DONE); + if (!dh) + goto nla_put_failure; + dh->minor = -1U; + dh->ret_code = NO_ERROR; + if (nla_put_notification_header(skb, NOTIFY_EXISTS)) + goto nla_put_failure; + genlmsg_end(skb, dh); + return; + +nla_put_failure: + nlmsg_free(skb); + pr_err("Error %d sending event. Event seq:%u\n", err, seq); +} + +static void free_state_changes(struct list_head *list) +{ + while (!list_empty(list)) { + struct drbd_state_change *state_change = + list_first_entry(list, struct drbd_state_change, list); + list_del(&state_change->list); + forget_state_change(state_change); + } +} + +static unsigned int notifications_for_state_change(struct drbd_state_change *state_change) +{ + return 1 + + state_change->n_connections + + state_change->n_devices + + state_change->n_devices * state_change->n_connections; +} + +static int get_initial_state(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct drbd_state_change *state_change = (struct drbd_state_change *)cb->args[0]; + unsigned int seq = cb->args[2]; + unsigned int n; + enum drbd_notification_type flags = 0; + + /* There is no need for taking notification_mutex here: it doesn't + matter if the initial state events mix with later state chage + events; we can always tell the events apart by the NOTIFY_EXISTS + flag. */ + + cb->args[5]--; + if (cb->args[5] == 1) { + notify_initial_state_done(skb, seq); + goto out; + } + n = cb->args[4]++; + if (cb->args[4] < cb->args[3]) + flags |= NOTIFY_CONTINUES; + if (n < 1) { + notify_resource_state_change(skb, seq, state_change->resource, + NOTIFY_EXISTS | flags); + goto next; + } + n--; + if (n < state_change->n_connections) { + notify_connection_state_change(skb, seq, &state_change->connections[n], + NOTIFY_EXISTS | flags); + goto next; + } + n -= state_change->n_connections; + if (n < state_change->n_devices) { + notify_device_state_change(skb, seq, &state_change->devices[n], + NOTIFY_EXISTS | flags); + goto next; + } + n -= state_change->n_devices; + if (n < state_change->n_devices * state_change->n_connections) { + notify_peer_device_state_change(skb, seq, &state_change->peer_devices[n], + NOTIFY_EXISTS | flags); + goto next; + } + +next: + if (cb->args[4] == cb->args[3]) { + struct drbd_state_change *next_state_change = + list_entry(state_change->list.next, + struct drbd_state_change, list); + cb->args[0] = (long)next_state_change; + cb->args[3] = notifications_for_state_change(next_state_change); + cb->args[4] = 0; + } +out: + return skb->len; +} + +int drbd_adm_get_initial_state(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct drbd_resource *resource; + LIST_HEAD(head); + + if (cb->args[5] >= 1) { + if (cb->args[5] > 1) + return get_initial_state(skb, cb); + if (cb->args[0]) { + struct drbd_state_change *state_change = + (struct drbd_state_change *)cb->args[0]; + + /* connect list to head */ + list_add(&head, &state_change->list); + free_state_changes(&head); + } + return 0; + } + + cb->args[5] = 2; /* number of iterations */ + mutex_lock(&resources_mutex); + for_each_resource(resource, &drbd_resources) { + struct drbd_state_change *state_change; + + state_change = remember_old_state(resource, GFP_KERNEL); + if (!state_change) { + if (!list_empty(&head)) + free_state_changes(&head); + mutex_unlock(&resources_mutex); + return -ENOMEM; + } + copy_old_to_new_state_change(state_change); + list_add_tail(&state_change->list, &head); + cb->args[5] += notifications_for_state_change(state_change); + } + mutex_unlock(&resources_mutex); + + if (!list_empty(&head)) { + struct drbd_state_change *state_change = + list_entry(head.next, struct drbd_state_change, list); + cb->args[0] = (long)state_change; + cb->args[3] = notifications_for_state_change(state_change); + list_del(&head); /* detach list from head */ + } + + cb->args[2] = cb->nlh->nlmsg_seq; + return get_initial_state(skb, cb); +} -- cgit v1.2.3-59-g8ed1b