From 51b0a488882328f8f02519bb47ca7e0e7fbe12ff Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 7 Jul 2017 07:44:59 -0500 Subject: block: Make bdrv_is_allocated_above() byte-based We are gradually moving away from sector-based interfaces, towards byte-based. In the common case, allocation is unlikely to ever use values that are not naturally sector-aligned, but it is possible that byte-based values will let us be more precise about allocation at the end of an unaligned file that can do byte-based access. Changing the signature of the function to use int64_t *pnum ensures that the compiler enforces that all callers are updated. For now, the io.c layer still assert()s that all callers are sector-aligned, but that can be relaxed when a later patch implements byte-based block status. Therefore, for the most part this patch is just the addition of scaling at the callers followed by inverse scaling at bdrv_is_allocated(). But some code, particularly stream_run(), gets a lot simpler because it no longer has to mess with sectors. Leave comments where we can further simplify by switching to byte-based iterations, once later patches eliminate the need for sector-aligned operations. For ease of review, bdrv_is_allocated() was tackled separately. Signed-off-by: Eric Blake Signed-off-by: Kevin Wolf --- block/replication.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) (limited to 'block/replication.c') diff --git a/block/replication.c b/block/replication.c index 8f3aba7a20..bf4462c8e7 100644 --- a/block/replication.c +++ b/block/replication.c @@ -264,7 +264,8 @@ static coroutine_fn int replication_co_writev(BlockDriverState *bs, BdrvChild *top = bs->file; BdrvChild *base = s->secondary_disk; BdrvChild *target; - int ret, n; + int ret; + int64_t n; ret = replication_get_io_status(s); if (ret < 0) { @@ -283,14 +284,20 @@ static coroutine_fn int replication_co_writev(BlockDriverState *bs, */ qemu_iovec_init(&hd_qiov, qiov->niov); while (remaining_sectors > 0) { - ret = bdrv_is_allocated_above(top->bs, base->bs, sector_num, - remaining_sectors, &n); + int64_t count; + + ret = bdrv_is_allocated_above(top->bs, base->bs, + sector_num * BDRV_SECTOR_SIZE, + remaining_sectors * BDRV_SECTOR_SIZE, + &count); if (ret < 0) { goto out1; } + assert(QEMU_IS_ALIGNED(count, BDRV_SECTOR_SIZE)); + n = count >> BDRV_SECTOR_BITS; qemu_iovec_reset(&hd_qiov); - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, n * BDRV_SECTOR_SIZE); + qemu_iovec_concat(&hd_qiov, qiov, bytes_done, count); target = ret ? top : base; ret = bdrv_co_writev(target, sector_num, n, &hd_qiov); @@ -300,7 +307,7 @@ static coroutine_fn int replication_co_writev(BlockDriverState *bs, remaining_sectors -= n; sector_num += n; - bytes_done += n * BDRV_SECTOR_SIZE; + bytes_done += count; } out1: -- cgit v1.2.1