Commit 4295c5fc authored by Max Reitz's avatar Max Reitz
Browse files

block/mirror: Pull out mirror_perform() 



When converting mirror's I/O to coroutines, we are going to need a point
where these coroutines are created.  mirror_perform() is going to be
that point.

Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarJeff Cody <jcody@redhat.com>
Reviewed-by: default avatarAlberto Garcia <berto@igalia.com>
Message-id: 20180613181823.13618-2-mreitz@redhat.com
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent f45280cb

block/mirror.c

+29 −22
Original line number Diff line number Diff line
@@ -80,6 +80,12 @@ typedef struct MirrorOp { 
    uint64_t bytes;

} MirrorOp;



typedef enum MirrorMethod {

    MIRROR_METHOD_COPY,

    MIRROR_METHOD_ZERO,

    MIRROR_METHOD_DISCARD,

} MirrorMethod;



static BlockErrorAction mirror_error_action(MirrorBlockJob *s, bool read,

                                            int error)

{
@@ -319,6 +325,22 @@ static void mirror_do_zero_or_discard(MirrorBlockJob *s, 
    }

}



static unsigned mirror_perform(MirrorBlockJob *s, int64_t offset,

                               unsigned bytes, MirrorMethod mirror_method)

{

    switch (mirror_method) {

    case MIRROR_METHOD_COPY:

        return mirror_do_read(s, offset, bytes);

    case MIRROR_METHOD_ZERO:

    case MIRROR_METHOD_DISCARD:

        mirror_do_zero_or_discard(s, offset, bytes,

                                  mirror_method == MIRROR_METHOD_DISCARD);

        return bytes;

    default:

        abort();

    }

}



static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)

{

    BlockDriverState *source = s->source;
@@ -385,11 +407,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) 
        int ret;

        int64_t io_bytes;

        int64_t io_bytes_acct;

        enum MirrorMethod {

            MIRROR_METHOD_COPY,

            MIRROR_METHOD_ZERO,

            MIRROR_METHOD_DISCARD

        } mirror_method = MIRROR_METHOD_COPY;

        MirrorMethod mirror_method = MIRROR_METHOD_COPY;



        assert(!(offset % s->granularity));

        ret = bdrv_block_status_above(source, NULL, offset,
@@ -427,23 +445,12 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) 
        }



        io_bytes = mirror_clip_bytes(s, offset, io_bytes);

        switch (mirror_method) {

        case MIRROR_METHOD_COPY:

            io_bytes = io_bytes_acct = mirror_do_read(s, offset, io_bytes);

            break;

        case MIRROR_METHOD_ZERO:

        case MIRROR_METHOD_DISCARD:

            mirror_do_zero_or_discard(s, offset, io_bytes,

                                      mirror_method == MIRROR_METHOD_DISCARD);

            if (write_zeroes_ok) {

        io_bytes = mirror_perform(s, offset, io_bytes, mirror_method);

        if (mirror_method != MIRROR_METHOD_COPY && write_zeroes_ok) {

            io_bytes_acct = 0;

        } else {

            io_bytes_acct = io_bytes;

        }

            break;

        default:

            abort();

        }

        assert(io_bytes);

        offset += io_bytes;

        nb_chunks -= DIV_ROUND_UP(io_bytes, s->granularity);
@@ -635,7 +642,7 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) 
                continue;

            }



            mirror_do_zero_or_discard(s, offset, bytes, false);

            mirror_perform(s, offset, bytes, MIRROR_METHOD_ZERO);

            offset += bytes;

        }