Commit 1743b515 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

qemu-nbd: move client handling to nbd.c 



This patch sets up the fd handler in nbd.c instead of qemu-nbd.c.  It
introduces NBDClient, which wraps the arguments to nbd_trip in a single
structure, so that we can add a notifier to it.  This way, qemu-nbd can
know about disconnections.

Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent a61c6782

nbd.c

+59 −3
Original line number Diff line number Diff line
@@ -600,6 +600,37 @@ struct NBDExport { 
    QSIMPLEQ_HEAD(, NBDRequest) requests;

};



struct NBDClient {

    int refcount;

    void (*close)(NBDClient *client);



    NBDExport *exp;

    int sock;

};



static void nbd_client_get(NBDClient *client)

{

    client->refcount++;

}



static void nbd_client_put(NBDClient *client)

{

    if (--client->refcount == 0) {

        g_free(client);

    }

}



static void nbd_client_close(NBDClient *client)

{

    qemu_set_fd_handler2(client->sock, NULL, NULL, NULL, NULL);

    close(client->sock);

    client->sock = -1;

    if (client->close) {

        client->close(client);

    }

    nbd_client_put(client);

}



static NBDRequest *nbd_request_get(NBDExport *exp)

{

    NBDRequest *req;
@@ -712,9 +743,11 @@ out: 
    return rc;

}



int nbd_trip(NBDExport *exp, int csock)

static int nbd_trip(NBDClient *client)

{

    NBDExport *exp = client->exp;

    NBDRequest *req = nbd_request_get(exp);

    int csock = client->sock;

    struct nbd_request request;

    struct nbd_reply reply;

    int rc = -1;
@@ -836,7 +869,30 @@ out: 
    return rc;

}



int nbd_negotiate(NBDExport *exp, int csock)

static void nbd_read(void *opaque)

{

    NBDClient *client = opaque;



    nbd_client_get(client);

    if (nbd_trip(client) != 0) {

        nbd_client_close(client);

    }



    nbd_client_put(client);

}



NBDClient *nbd_client_new(NBDExport *exp, int csock,

                          void (*close)(NBDClient *))

{

    return nbd_send_negotiate(csock, exp->size, exp->nbdflags);

    NBDClient *client;

    if (nbd_send_negotiate(csock, exp->size, exp->nbdflags) == -1) {

        return NULL;

    }

    client = g_malloc0(sizeof(NBDClient));

    client->refcount = 1;

    client->exp = exp;

    client->sock = csock;

    client->close = close;

    qemu_set_fd_handler2(csock, NULL, nbd_read, NULL, client);

    return client;

}

nbd.h

+3 −2
Original line number Diff line number Diff line
@@ -76,11 +76,12 @@ int nbd_client(int fd); 
int nbd_disconnect(int fd);



typedef struct NBDExport NBDExport;

typedef struct NBDClient NBDClient;



NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset,

                          off_t size, uint32_t nbdflags);

void nbd_export_close(NBDExport *exp);

int nbd_negotiate(NBDExport *exp, int csock);

int nbd_trip(NBDExport *exp, int csock);

NBDClient *nbd_client_new(NBDExport *exp, int csock,

                          void (*close)(NBDClient *));



#endif

qemu-nbd.c

+4 −10
Original line number Diff line number Diff line
@@ -249,15 +249,10 @@ static int nbd_can_accept(void *opaque) 
    return nb_fds < shared;

}



static void nbd_read(void *opaque)

static void nbd_client_closed(NBDClient *client)

{

    int fd = (uintptr_t) opaque;



    if (nbd_trip(exp, fd) != 0) {

        qemu_set_fd_handler2(fd, NULL, NULL, NULL, NULL);

        close(fd);

    nb_fds--;

    }

    qemu_notify_event();

}



static void nbd_accept(void *opaque)
@@ -268,8 +263,7 @@ static void nbd_accept(void *opaque) 


    int fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len);

    nbd_started = true;

    if (fd != -1 && nbd_negotiate(exp, fd) != -1) {

        qemu_set_fd_handler2(fd, NULL, nbd_read, NULL, (void *) (intptr_t) fd);

    if (fd != -1 && nbd_client_new(exp, fd, nbd_client_closed)) {

        nb_fds++;

    }

}