> The only solution I came up with is to add before/after hooks in the block
> job. I agree with the criticism, but I think it's general enough and at the
> same
> time easy enough to implement.
>
> > IMHO, the current implementation is quite simple and easy to maintain.
>
> No, "if (bs->backup_info)" simply doesn't belong in bdrv_co_writev.
I do not really understand that argument, because the current COPY_ON_READ
implementation also works that way:
if (bs->copy_on_read) {
flags |= BDRV_REQ_COPY_ON_READ;
}
if (flags & BDRV_REQ_COPY_ON_READ) {
bs->copy_on_read_in_flight++;
}
if (bs->copy_on_read_in_flight) {
wait_for_overlapping_requests(bs, sector_num, nb_sectors);
}
tracked_request_begin(&req, bs, sector_num, nb_sectors, false);
if (flags & BDRV_REQ_COPY_ON_READ) {
...
Or do you also want to move that to block job hooks?
