Commit 52a46505 authored by Eric Blake's avatar Eric Blake Committed by Kevin Wolf
Browse files

nbd: Simplify client FUA handling 



Now that the block layer honors per-bds FUA support, we don't
have to duplicate the fallback flush at the NBD layer.  The
static function nbd_co_writev_flags() is no longer needed, and
the driver can just directly use nbd_client_co_writev().

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Acked-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 465fe887

block/nbd-client.c

+4 −4
Original line number Diff line number Diff line
@@ -243,15 +243,15 @@ static int nbd_co_readv_1(BlockDriverState *bs, int64_t sector_num, 


static int nbd_co_writev_1(BlockDriverState *bs, int64_t sector_num,

                           int nb_sectors, QEMUIOVector *qiov,

                           int offset, int *flags)

                           int offset, int flags)

{

    NbdClientSession *client = nbd_get_client_session(bs);

    struct nbd_request request = { .type = NBD_CMD_WRITE };

    struct nbd_reply reply;

    ssize_t ret;



    if ((*flags & BDRV_REQ_FUA) && (client->nbdflags & NBD_FLAG_SEND_FUA)) {

        *flags &= ~BDRV_REQ_FUA;

    if (flags & BDRV_REQ_FUA) {

        assert(client->nbdflags & NBD_FLAG_SEND_FUA);

        request.type |= NBD_CMD_FLAG_FUA;

    }
@@ -291,7 +291,7 @@ int nbd_client_co_readv(BlockDriverState *bs, int64_t sector_num, 
}



int nbd_client_co_writev(BlockDriverState *bs, int64_t sector_num,

                         int nb_sectors, QEMUIOVector *qiov, int *flags)

                         int nb_sectors, QEMUIOVector *qiov, int flags)

{

    int offset = 0;

    int ret;

block/nbd-client.h

+1 −1
Original line number Diff line number Diff line
@@ -48,7 +48,7 @@ int nbd_client_co_discard(BlockDriverState *bs, int64_t sector_num, 
                          int nb_sectors);

int nbd_client_co_flush(BlockDriverState *bs);

int nbd_client_co_writev(BlockDriverState *bs, int64_t sector_num,

                         int nb_sectors, QEMUIOVector *qiov, int *flags);

                         int nb_sectors, QEMUIOVector *qiov, int flags);

int nbd_client_co_readv(BlockDriverState *bs, int64_t sector_num,

                        int nb_sectors, QEMUIOVector *qiov);

block/nbd.c

+3 −22
Original line number Diff line number Diff line
@@ -355,25 +355,6 @@ static int nbd_co_readv(BlockDriverState *bs, int64_t sector_num, 
    return nbd_client_co_readv(bs, sector_num, nb_sectors, qiov);

}



static int nbd_co_writev_flags(BlockDriverState *bs, int64_t sector_num,

                               int nb_sectors, QEMUIOVector *qiov, int flags)

{

    int ret;



    ret = nbd_client_co_writev(bs, sector_num, nb_sectors, qiov, &flags);

    if (ret < 0) {

        return ret;

    }



    /* The flag wasn't sent to the server, so we need to emulate it with an

     * explicit flush */

    if (flags & BDRV_REQ_FUA) {

        ret = nbd_client_co_flush(bs);

    }



    return ret;

}



static int nbd_co_flush(BlockDriverState *bs)

{

    return nbd_client_co_flush(bs);
@@ -470,7 +451,7 @@ static BlockDriver bdrv_nbd = { 
    .bdrv_parse_filename        = nbd_parse_filename,

    .bdrv_file_open             = nbd_open,

    .bdrv_co_readv              = nbd_co_readv,

    .bdrv_co_writev_flags       = nbd_co_writev_flags,

    .bdrv_co_writev_flags       = nbd_client_co_writev,

    .bdrv_close                 = nbd_close,

    .bdrv_co_flush_to_os        = nbd_co_flush,

    .bdrv_co_discard            = nbd_co_discard,
@@ -488,7 +469,7 @@ static BlockDriver bdrv_nbd_tcp = { 
    .bdrv_parse_filename        = nbd_parse_filename,

    .bdrv_file_open             = nbd_open,

    .bdrv_co_readv              = nbd_co_readv,

    .bdrv_co_writev_flags       = nbd_co_writev_flags,

    .bdrv_co_writev_flags       = nbd_client_co_writev,

    .bdrv_close                 = nbd_close,

    .bdrv_co_flush_to_os        = nbd_co_flush,

    .bdrv_co_discard            = nbd_co_discard,
@@ -506,7 +487,7 @@ static BlockDriver bdrv_nbd_unix = { 
    .bdrv_parse_filename        = nbd_parse_filename,

    .bdrv_file_open             = nbd_open,

    .bdrv_co_readv              = nbd_co_readv,

    .bdrv_co_writev_flags       = nbd_co_writev_flags,

    .bdrv_co_writev_flags       = nbd_client_co_writev,

    .bdrv_close                 = nbd_close,

    .bdrv_co_flush_to_os        = nbd_co_flush,

    .bdrv_co_discard            = nbd_co_discard,