On Wed, Feb 28, 2018 at 07:04:55PM +0100, Max Reitz wrote:
> 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: Max Reitz <mre...@redhat.com>
> Reviewed-by: Fam Zheng <f...@redhat.com>
> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
> ---
> block/mirror.c | 51 +++++++++++++++++++++++++++++----------------------
> 1 file changed, 29 insertions(+), 22 deletions(-)
>
> diff --git a/block/mirror.c b/block/mirror.c
> index f5bf620942..d197c8936e 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -82,6 +82,12 @@ 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)
> {
> @@ -321,6 +327,22 @@ 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;
> @@ -387,11 +409,7 @@ 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,
> @@ -429,22 +447,11 @@ 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_acct = 0;
> - } else {
> - io_bytes_acct = io_bytes;
> - }
> - break;
> - default:
> - abort();
> + 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;
> }
> assert(io_bytes);
> offset += io_bytes;
> @@ -638,7 +645,7 @@ 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;
> }
>
> --
> 2.14.3
>
>
Reviewed-by: Jeff Cody <jc...@redhat.com>
