Commit af8b7d2b authored by Juan Quintela's avatar Juan Quintela
Browse files

migration: Transmit initial package through the multifd channels 



Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
Reviewed-by: default avatarDaniel P. Berrangé <berrange@redhat.com>

--

Be network agnostic.
Add error checking for all values.
parent 36c2f8be

migration/ram.c

+99 −5
Original line number Diff line number Diff line
@@ -52,6 +52,8 @@ 
#include "qemu/rcu_queue.h"

#include "migration/colo.h"

#include "migration/block.h"

#include "sysemu/sysemu.h"

#include "qemu/uuid.h"



/***********************************************************/

/* ram save/restore */
@@ -433,6 +435,16 @@ exit: 


/* Multiple fd's */



#define MULTIFD_MAGIC 0x11223344U

#define MULTIFD_VERSION 1



typedef struct {

    uint32_t magic;

    uint32_t version;

    unsigned char uuid[16]; /* QemuUUID */

    uint8_t id;

} __attribute__((packed)) MultiFDInit_t;



struct MultiFDSendParams {

    uint8_t id;

    char *name;
@@ -445,6 +457,68 @@ struct MultiFDSendParams { 
};

typedef struct MultiFDSendParams MultiFDSendParams;



static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)

{

    MultiFDInit_t msg;

    int ret;



    msg.magic = cpu_to_be32(MULTIFD_MAGIC);

    msg.version = cpu_to_be32(MULTIFD_VERSION);

    msg.id = p->id;

    memcpy(msg.uuid, &qemu_uuid.data, sizeof(msg.uuid));



    ret = qio_channel_write_all(p->c, (char *)&msg, sizeof(msg), errp);

    if (ret != 0) {

        return -1;

    }

    return 0;

}



static int multifd_recv_initial_packet(QIOChannel *c, Error **errp)

{

    MultiFDInit_t msg;

    int ret;



    ret = qio_channel_read_all(c, (char *)&msg, sizeof(msg), errp);

    if (ret != 0) {

        return -1;

    }



    be32_to_cpus(&msg.magic);

    be32_to_cpus(&msg.version);



    if (msg.magic != MULTIFD_MAGIC) {

        error_setg(errp, "multifd: received packet magic %x "

                   "expected %x", msg.magic, MULTIFD_MAGIC);

        return -1;

    }



    if (msg.version != MULTIFD_VERSION) {

        error_setg(errp, "multifd: received packet version %d "

                   "expected %d", msg.version, MULTIFD_VERSION);

        return -1;

    }



    if (memcmp(msg.uuid, &qemu_uuid, sizeof(qemu_uuid))) {

        char *uuid = qemu_uuid_unparse_strdup(&qemu_uuid);

        char *msg_uuid = qemu_uuid_unparse_strdup((const QemuUUID *)msg.uuid);



        error_setg(errp, "multifd: received uuid '%s' and expected "

                   "uuid '%s' for channel %hhd", msg_uuid, uuid, msg.id);

        g_free(uuid);

        g_free(msg_uuid);

        return -1;

    }



    if (msg.id > migrate_multifd_channels()) {

        error_setg(errp, "multifd: received channel version %d "

                   "expected %d", msg.version, MULTIFD_VERSION);

        return -1;

    }



    return msg.id;

}



struct {

    MultiFDSendParams *params;

    /* number of created threads */
@@ -509,6 +583,11 @@ int multifd_save_cleanup(Error **errp) 
static void *multifd_send_thread(void *opaque)

{

    MultiFDSendParams *p = opaque;

    Error *local_err = NULL;



    if (multifd_send_initial_packet(p, &local_err) < 0) {

        goto out;

    }



    while (true) {

        qemu_mutex_lock(&p->mutex);
@@ -520,6 +599,11 @@ static void *multifd_send_thread(void *opaque) 
        qemu_sem_wait(&p->sem);

    }



out:

    if (local_err) {

        multifd_send_terminate_threads(local_err);

    }



    qemu_mutex_lock(&p->mutex);

    p->running = false;

    qemu_mutex_unlock(&p->mutex);
@@ -704,12 +788,22 @@ bool multifd_recv_all_channels_created(void) 
void multifd_recv_new_channel(QIOChannel *ioc)

{

    MultiFDRecvParams *p;

    /* we need to invent channels id's until we transmit */

    /* we will remove this on a later patch */

    static int i;

    Error *local_err = NULL;

    int id;



    p = &multifd_recv_state->params[i];

    i++;

    id = multifd_recv_initial_packet(ioc, &local_err);

    if (id < 0) {

        multifd_recv_terminate_threads(local_err);

        return;

    }



    p = &multifd_recv_state->params[id];

    if (p->c != NULL) {

        error_setg(&local_err, "multifd: received id '%d' already setup'",

                   id);

        multifd_recv_terminate_threads(local_err);

        return;

    }

    p->c = ioc;

    object_ref(OBJECT(ioc));