Commit 030fa7f6 authored by Eric Blake's avatar Eric Blake
Browse files

nbd: Use new qio_channel_*_all() functions 



Rather than open-coding our own read/write-all functions, we
can make use of the recently-added qio code.  It slightly
changes the error message in one of the iotests.

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-Id: <20170905191114.5959-4-eblake@redhat.com>
Reviewed-by: default avatarDaniel P. Berrange <berrange@redhat.com>
parent e8ffaa31

block/nbd-client.c

+7 −8
Original line number Diff line number Diff line
@@ -121,7 +121,7 @@ static int nbd_co_send_request(BlockDriverState *bs, 
                               QEMUIOVector *qiov)

{

    NBDClientSession *s = nbd_get_client_session(bs);

    int rc, ret, i;

    int rc, i;



    qemu_co_mutex_lock(&s->send_mutex);

    while (s->in_flight == MAX_NBD_REQUESTS) {
@@ -156,9 +156,9 @@ static int nbd_co_send_request(BlockDriverState *bs, 
        qio_channel_set_cork(s->ioc, true);

        rc = nbd_send_request(s->ioc, request);

        if (rc >= 0 && !s->quit) {

            ret = nbd_rwv(s->ioc, qiov->iov, qiov->niov, request->len, false,

                          NULL);

            if (ret != request->len) {

            assert(request->len == iov_size(qiov->iov, qiov->niov));

            if (qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov,

                                       NULL) < 0) {

                rc = -EIO;

            }

        }
@@ -184,7 +184,6 @@ static void nbd_co_receive_reply(NBDClientSession *s, 
                                 QEMUIOVector *qiov)

{

    int i = HANDLE_TO_INDEX(s, request->handle);

    int ret;



    /* Wait until we're woken up by nbd_read_reply_entry.  */

    s->requests[i].receiving = true;
@@ -195,9 +194,9 @@ static void nbd_co_receive_reply(NBDClientSession *s, 
        reply->error = EIO;

    } else {

        if (qiov && reply->error == 0) {

            ret = nbd_rwv(s->ioc, qiov->iov, qiov->niov, request->len, true,

                          NULL);

            if (ret != request->len) {

            assert(request->len == iov_size(qiov->iov, qiov->niov));

            if (qio_channel_readv_all(s->ioc, qiov->iov, qiov->niov,

                                      NULL) < 0) {

                reply->error = EIO;

                s->quit = true;

            }

include/block/nbd.h

+0 −2
Original line number Diff line number Diff line
@@ -155,8 +155,6 @@ struct NBDExportInfo { 
};

typedef struct NBDExportInfo NBDExportInfo;



ssize_t nbd_rwv(QIOChannel *ioc, struct iovec *iov, size_t niov, size_t length,

                bool do_read, Error **errp);

int nbd_receive_negotiate(QIOChannel *ioc, const char *name,

                          QCryptoTLSCreds *tlscreds, const char *hostname,

                          QIOChannel **outioc, NBDExportInfo *info,

nbd/common.c

+0 −45
Original line number Diff line number Diff line
@@ -20,51 +20,6 @@ 
#include "qapi/error.h"

#include "nbd-internal.h"



/* nbd_wr_syncv

 * The function may be called from coroutine or from non-coroutine context.

 * When called from non-coroutine context @ioc must be in blocking mode.

 */

ssize_t nbd_rwv(QIOChannel *ioc, struct iovec *iov, size_t niov, size_t length,

                bool do_read, Error **errp)

{

    ssize_t done = 0;

    struct iovec *local_iov = g_new(struct iovec, niov);

    struct iovec *local_iov_head = local_iov;

    unsigned int nlocal_iov = niov;



    nlocal_iov = iov_copy(local_iov, nlocal_iov, iov, niov, 0, length);



    while (nlocal_iov > 0) {

        ssize_t len;

        if (do_read) {

            len = qio_channel_readv(ioc, local_iov, nlocal_iov, errp);

        } else {

            len = qio_channel_writev(ioc, local_iov, nlocal_iov, errp);

        }

        if (len == QIO_CHANNEL_ERR_BLOCK) {

            /* errp should not be set */

            assert(qemu_in_coroutine());

            qio_channel_yield(ioc, do_read ? G_IO_IN : G_IO_OUT);

            continue;

        }

        if (len < 0) {

            done = -EIO;

            goto cleanup;

        }



        if (do_read && len == 0) {

            break;

        }



        iov_discard_front(&local_iov, &nlocal_iov, len);

        done += len;

    }



 cleanup:

    g_free(local_iov_head);

    return done;

}



/* Discard length bytes from channel.  Return -errno on failure and 0 on

 * success */

int nbd_drop(QIOChannel *ioc, size_t size, Error **errp)

nbd/nbd-internal.h

+7 −34
Original line number Diff line number Diff line
@@ -85,28 +85,14 @@ 
static inline int nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size,

                               Error **errp)

{

    struct iovec iov = { .iov_base = buffer, .iov_len = size };

    ssize_t ret;



    /* Sockets are kept in blocking mode in the negotiation phase.  After

     * that, a non-readable socket simply means that another thread stole

     * our request/reply.  Synchronization is done with recv_coroutine, so

     * that this is coroutine-safe.

     */

    int ret;



    assert(size);



    ret = nbd_rwv(ioc, &iov, 1, size, true, errp);

    if (ret <= 0) {

        return ret;

    ret = qio_channel_read_all_eof(ioc, buffer, size, errp);

    if (ret < 0) {

        ret = -EIO;

    }



    if (ret != size) {

        error_setg(errp, "End of file");

        return -EINVAL;

    }



    return 1;

    return ret;

}



/* nbd_read
@@ -115,14 +101,7 @@ static inline int nbd_read_eof(QIOChannel *ioc, void *buffer, size_t size, 
static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size,

                           Error **errp)

{

    int ret = nbd_read_eof(ioc, buffer, size, errp);



    if (ret == 0) {

        ret = -EINVAL;

        error_setg(errp, "End of file");

    }



    return ret < 0 ? ret : 0;

    return qio_channel_read_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;

}



/* nbd_write
@@ -131,13 +110,7 @@ static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size, 
static inline int nbd_write(QIOChannel *ioc, const void *buffer, size_t size,

                            Error **errp)

{

    struct iovec iov = { .iov_base = (void *) buffer, .iov_len = size };



    ssize_t ret = nbd_rwv(ioc, &iov, 1, size, false, errp);



    assert(ret < 0 || ret == size);



    return ret < 0 ? ret : 0;

    return qio_channel_write_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;

}



struct NBDTLSHandshakeData {

tests/qemu-iotests/083.out

+4 −4
Original line number Diff line number Diff line
@@ -69,12 +69,12 @@ read failed: Input/output error 


=== Check disconnect 4 reply ===



End of file

Unexpected end-of-file before all bytes were read

read failed: Input/output error



=== Check disconnect 8 reply ===



End of file

Unexpected end-of-file before all bytes were read

read failed: Input/output error



=== Check disconnect before data ===
@@ -180,12 +180,12 @@ read failed: Input/output error 


=== Check disconnect 4 reply ===



End of file

Unexpected end-of-file before all bytes were read

read failed: Input/output error



=== Check disconnect 8 reply ===



End of file

Unexpected end-of-file before all bytes were read

read failed: Input/output error



=== Check disconnect before data ===