ovn-controller: Create tunnels based on Chassis configuration.

[mirror_ovs.git] / ovn / controller / chassis.c

/* Copyright (c) 2015 Nicira, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <config.h>
#include "chassis.h"

#include "lib/hash.h"
#include "lib/poll-loop.h"
#include "lib/sset.h"
#include "lib/util.h"
#include "lib/vswitch-idl.h"
#include "openvswitch/vlog.h"
#include "ovn/lib/ovn-sb-idl.h"
#include "ovn-controller.h"

VLOG_DEFINE_THIS_MODULE(chassis);

void
chassis_init(struct controller_ctx *ctx)
{
    ovsdb_idl_add_table(ctx->ovs_idl, &ovsrec_table_open_vswitch);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_open_vswitch_col_external_ids);
    ovsdb_idl_add_table(ctx->ovs_idl, &ovsrec_table_bridge);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_bridge_col_ports);
    ovsdb_idl_add_table(ctx->ovs_idl, &ovsrec_table_port);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_port_col_name);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_port_col_interfaces);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_port_col_external_ids);
    ovsdb_idl_add_table(ctx->ovs_idl, &ovsrec_table_interface);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_interface_col_name);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_interface_col_type);
    ovsdb_idl_add_column(ctx->ovs_idl, &ovsrec_interface_col_options);
}

static void
register_chassis(struct controller_ctx *ctx)
{
    const struct sbrec_chassis *chassis_rec;
    const struct ovsrec_open_vswitch *cfg;
    const char *encap_type, *encap_ip;
    struct sbrec_encap *encap_rec;
    static bool inited = false;
    int retval = TXN_TRY_AGAIN;
    struct ovsdb_idl_txn *txn;

    SBREC_CHASSIS_FOR_EACH(chassis_rec, ctx->ovnsb_idl) {
        if (!strcmp(chassis_rec->name, ctx->chassis_id)) {
            break;
        }
    }

    /* xxx Need to support more than one encap.  Also need to support
     * xxx encap options. */
    cfg = ovsrec_open_vswitch_first(ctx->ovs_idl);
    if (!cfg) {
        VLOG_INFO("No Open_vSwitch row defined.");
        return;
    }

    encap_type = smap_get(&cfg->external_ids, "ovn-encap-type");
    encap_ip = smap_get(&cfg->external_ids, "ovn-encap-ip");
    if (!encap_type || !encap_ip) {
        VLOG_INFO("Need to specify an encap type and ip");
        return;
    }

    if (chassis_rec) {
        int i;

        for (i = 0; i < chassis_rec->n_encaps; i++) {
            if (!strcmp(chassis_rec->encaps[i]->type, encap_type)
                && !strcmp(chassis_rec->encaps[i]->ip, encap_ip)) {
                /* Nothing changed. */
                inited = true;
                return;
            } else if (!inited) {
                VLOG_WARN("Chassis config changing on startup, make sure "
                          "multiple chassis are not configured : %s/%s->%s/%s",
                          chassis_rec->encaps[i]->type,
                          chassis_rec->encaps[i]->ip,
                          encap_type, encap_ip);
            }

        }
    }

    txn = ovsdb_idl_txn_create(ctx->ovnsb_idl);
    ovsdb_idl_txn_add_comment(txn,
                              "ovn-controller: registering chassis '%s'",
                              ctx->chassis_id);

    if (!chassis_rec) {
        chassis_rec = sbrec_chassis_insert(txn);
        sbrec_chassis_set_name(chassis_rec, ctx->chassis_id);
    }

    encap_rec = sbrec_encap_insert(txn);

    sbrec_encap_set_type(encap_rec, encap_type);
    sbrec_encap_set_ip(encap_rec, encap_ip);

    sbrec_chassis_set_encaps(chassis_rec, &encap_rec, 1);

    retval = ovsdb_idl_txn_commit_block(txn);
    if (retval != TXN_SUCCESS && retval != TXN_UNCHANGED) {
        VLOG_INFO("Problem registering chassis: %s",
                  ovsdb_idl_txn_status_to_string(retval));
        poll_immediate_wake();
    }
    ovsdb_idl_txn_destroy(txn);

    inited = true;
}

/* Enough context to create a new tunnel, using tunnel_add(). */
struct tunnel_ctx {
    /* Contains "struct port_hash_node"s.  Used to figure out what
     * existing tunnels should be deleted: we index all of the OVN encap
     * rows into this data structure, then as existing rows are
     * generated we remove them.  After generating all the rows, any
     * remaining in 'tunnel_hmap' must be deleted from the database. */
    struct hmap tunnel_hmap;

    /* Names of all ports in the bridge, to allow checking uniqueness when
     * adding a new tunnel. */
    struct sset port_names;

    struct ovsdb_idl_txn *ovs_txn;
    const struct ovsrec_bridge *br_int;
};

struct port_hash_node {
    struct hmap_node node;
    const struct ovsrec_port *port;
    const struct ovsrec_bridge *bridge;
};

static size_t
port_hash(const char *chassis_id, const char *type, const char *ip)
{
    size_t hash = hash_string(chassis_id, 0);
    hash = hash_string(type, hash);
    return hash_string(ip, hash);
}

static size_t
port_hash_rec(const struct ovsrec_port *port)
{
    const char *chassis_id, *ip;
    const struct ovsrec_interface *iface;

    chassis_id = smap_get(&port->external_ids, "ovn-chassis-id");

    if (!chassis_id || !port->n_interfaces) {
        /* This should not happen for an OVN-created port. */
        return 0;
    }

    iface = port->interfaces[0];
    ip = smap_get(&iface->options, "remote_ip");

    return port_hash(chassis_id, iface->type, ip);
}

static char *
tunnel_create_name(struct tunnel_ctx *tc, const char *chassis_id)
{
    int i;

    for (i = 0; i < UINT16_MAX; i++) {
        char *port_name;
        port_name = xasprintf("ovn-%.6s-%x", chassis_id, i);

        if (!sset_contains(&tc->port_names, port_name)) {
            return port_name;
        }

        free(port_name);
    }

    return NULL;
}


static void
tunnel_add(struct tunnel_ctx *tc, const char *new_chassis_id,
           const struct sbrec_encap *encap)
{
    struct port_hash_node *hash_node;

    /* Check whether such a row already exists in OVS.  If so, remove it
     * from 'tc->tunnel_hmap' and we're done. */
    HMAP_FOR_EACH_WITH_HASH (hash_node, node,
                             port_hash(new_chassis_id,
                                       encap->type, encap->ip),
                             &tc->tunnel_hmap) {
        const struct ovsrec_port *port = hash_node->port;
        const char *chassis_id = smap_get(&port->external_ids,
                                          "ovn-chassis-id");
        const struct ovsrec_interface *iface;
        const char *ip;

        if (!chassis_id || !port->n_interfaces) {
            continue;
        }

        iface = port->interfaces[0];
        ip = smap_get(&iface->options, "remote_ip");
        if (!ip) {
            continue;
        }

        if (!strcmp(new_chassis_id, chassis_id)
            && !strcmp(encap->type, iface->type)
            && !strcmp(encap->ip, ip)) {
            hmap_remove(&tc->tunnel_hmap, &hash_node->node);
            free(hash_node);
            return;
        }
    }

    /* No such port, so add one. */
    struct smap external_ids = SMAP_INITIALIZER(&external_ids);
    struct smap options = SMAP_INITIALIZER(&options);
    struct ovsrec_port *port, **ports;
    struct ovsrec_interface *iface;
    char *port_name;
    size_t i;

    port_name = tunnel_create_name(tc, new_chassis_id);
    if (!port_name) {
        VLOG_WARN("Unable to allocate unique name for '%s' tunnel",
                  new_chassis_id);
        return;
    }

    iface = ovsrec_interface_insert(tc->ovs_txn);
    ovsrec_interface_set_name(iface, port_name);
    ovsrec_interface_set_type(iface, encap->type);
    smap_add(&options, "remote_ip", encap->ip);
    smap_add(&options, "key", "flow");
    ovsrec_interface_set_options(iface, &options);
    smap_destroy(&options);

    port = ovsrec_port_insert(tc->ovs_txn);
    ovsrec_port_set_name(port, port_name);
    ovsrec_port_set_interfaces(port, &iface, 1);
    smap_add(&external_ids, "ovn-chassis-id", new_chassis_id);
    ovsrec_port_set_external_ids(port, &external_ids);
    smap_destroy(&external_ids);

    ports = xmalloc(sizeof *tc->br_int->ports * (tc->br_int->n_ports + 1));
    for (i = 0; i < tc->br_int->n_ports; i++) {
        ports[i] = tc->br_int->ports[i];
    }
    ports[tc->br_int->n_ports] = port;
    ovsrec_bridge_set_ports(tc->br_int, ports, tc->br_int->n_ports + 1);

    sset_add(&tc->port_names, port_name);
    free(port_name);
    free(ports);
}

static void
bridge_delete_port(const struct ovsrec_bridge *br,
                   const struct ovsrec_port *port)
{
    struct ovsrec_port **ports;
    size_t i, n;

    ports = xmalloc(sizeof *br->ports * br->n_ports);
    for (i = n = 0; i < br->n_ports; i++) {
        if (br->ports[i] != port) {
            ports[n++] = br->ports[i];
        }
    }
    ovsrec_bridge_set_ports(br, ports, n);
    free(ports);
}

static struct sbrec_encap *
preferred_encap(const struct sbrec_chassis *chassis_rec)
{
    size_t i;

    /* For hypervisors, we only support Geneve and STT encapsulations.
     * Sets are returned alphabetically, so "geneve" will be preferred
     * over "stt". */
    for (i = 0; i < chassis_rec->n_encaps; i++) {
        if (!strcmp(chassis_rec->encaps[i]->type, "geneve")
                || !strcmp(chassis_rec->encaps[i]->type, "stt")) {
            return chassis_rec->encaps[i];
        }
    }

    return NULL;
}

static void
update_encaps(struct controller_ctx *ctx)
{
    const struct sbrec_chassis *chassis_rec;
    const struct ovsrec_bridge *br;
    int retval;

    struct tunnel_ctx tc = {
        .tunnel_hmap = HMAP_INITIALIZER(&tc.tunnel_hmap),
        .port_names = SSET_INITIALIZER(&tc.port_names),
        .br_int = ctx->br_int
    };

    tc.ovs_txn = ovsdb_idl_txn_create(ctx->ovs_idl);
    ovsdb_idl_txn_add_comment(tc.ovs_txn,
                              "ovn-controller: modifying OVS tunnels '%s'",
                              ctx->chassis_id);

    /* Collect all port names into tc.port_names.
     *
     * Collect all the OVN-created tunnels into tc.tunnel_hmap. */
    OVSREC_BRIDGE_FOR_EACH(br, ctx->ovs_idl) {
        size_t i;

        for (i = 0; i < br->n_ports; i++) {
            const struct ovsrec_port *port = br->ports[i];

            sset_add(&tc.port_names, port->name);

            if (smap_get(&port->external_ids, "ovn-chassis-id")) {
                struct port_hash_node *hash_node = xzalloc(sizeof *hash_node);
                hash_node->bridge = br;
                hash_node->port = port;
                hmap_insert(&tc.tunnel_hmap, &hash_node->node,
                            port_hash_rec(port));
            }
        }
    }

    SBREC_CHASSIS_FOR_EACH(chassis_rec, ctx->ovnsb_idl) {
        if (strcmp(chassis_rec->name, ctx->chassis_id)) {
            /* Create tunnels to the other chassis. */
            const struct sbrec_encap *encap = preferred_encap(chassis_rec);
            if (!encap) {
                VLOG_INFO("No supported encaps for '%s'", chassis_rec->name);
                continue;
            }
            tunnel_add(&tc, chassis_rec->name, encap);
        }
    }

    /* Delete any existing OVN tunnels that were not still around. */
    struct port_hash_node *hash_node, *next_hash_node;
    HMAP_FOR_EACH_SAFE (hash_node, next_hash_node, node, &tc.tunnel_hmap) {
        hmap_remove(&tc.tunnel_hmap, &hash_node->node);
        bridge_delete_port(hash_node->bridge, hash_node->port);
        free(hash_node);
    }
    hmap_destroy(&tc.tunnel_hmap);
    sset_destroy(&tc.port_names);

    retval = ovsdb_idl_txn_commit_block(tc.ovs_txn);
    if (retval != TXN_SUCCESS && retval != TXN_UNCHANGED) {
        VLOG_INFO("Problem modifying OVS tunnels: %s",
                  ovsdb_idl_txn_status_to_string(retval));
        poll_immediate_wake();
    }
    ovsdb_idl_txn_destroy(tc.ovs_txn);
}

void
chassis_run(struct controller_ctx *ctx)
{
    register_chassis(ctx);
    update_encaps(ctx);
}

void
chassis_destroy(struct controller_ctx *ctx)
{
    int retval = TXN_TRY_AGAIN;

    ovs_assert(ctx->ovnsb_idl);

    while (retval != TXN_SUCCESS && retval != TXN_UNCHANGED) {
        const struct sbrec_chassis *chassis_rec;
        struct ovsdb_idl_txn *txn;

        SBREC_CHASSIS_FOR_EACH(chassis_rec, ctx->ovnsb_idl) {
            if (!strcmp(chassis_rec->name, ctx->chassis_id)) {
                break;
            }
        }

        if (!chassis_rec) {
            break;
        }

        txn = ovsdb_idl_txn_create(ctx->ovnsb_idl);
        ovsdb_idl_txn_add_comment(txn,
                                  "ovn-controller: unregistering chassis '%s'",
                                  ctx->chassis_id);
        sbrec_chassis_delete(chassis_rec);

        retval = ovsdb_idl_txn_commit_block(txn);
        if (retval == TXN_ERROR) {
            VLOG_INFO("Problem unregistering chassis: %s",
                      ovsdb_idl_txn_status_to_string(retval));
        }
        ovsdb_idl_txn_destroy(txn);
    }

    retval = TXN_TRY_AGAIN;
    while (retval != TXN_SUCCESS && retval != TXN_UNCHANGED) {
        struct ovsrec_port **ports;
        struct ovsdb_idl_txn *txn;
        size_t i, n;

        txn = ovsdb_idl_txn_create(ctx->ovs_idl);
        ovsdb_idl_txn_add_comment(txn,
                                  "ovn-controller: destroying tunnels");

        /* Delete all the OVS-created tunnels from the integration
         * bridge. */
        ports = xmalloc(sizeof *ctx->br_int->ports * ctx->br_int->n_ports);
        for (i = n = 0; i < ctx->br_int->n_ports; i++) {
            if (!smap_get(&ctx->br_int->ports[i]->external_ids,
                          "ovn-chassis-id")) {
                ports[n++] = ctx->br_int->ports[i];
            }
        }
        ovsrec_bridge_set_ports(ctx->br_int, ports, n);
        free(ports);

        retval = ovsdb_idl_txn_commit_block(txn);
        if (retval == TXN_ERROR) {
            VLOG_INFO("Problem destroying tunnels: %s",
                      ovsdb_idl_txn_status_to_string(retval));
        }
        ovsdb_idl_txn_destroy(txn);
    }
}