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vhdx: DIV_ROUND_UP() in vhdx_calc_bat_entries() 

We have DIV_ROUND_UP(), so we can use it to produce more easily readable
code. It may be slower than the bit shifting currently performed
(because it actually performs a division), but since
vhdx_calc_bat_entries() is never used in a hot path, this is completely
fine.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 1450451066-13335-2-git-send-email-mreitz@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
This commit is contained in:
Max Reitz 2015-12-18 16:04:25 +01:00 committed by Jeff Cody
parent b189346eb1
commit 939901dcd2
1 changed files with 2 additions and 8 deletions
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block/vhdx.c
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@ -857,14 +857,8 @@ static void vhdx_calc_bat_entries(BDRVVHDXState *s)
{
uint32_t data_blocks_cnt, bitmap_blocks_cnt;
data_blocks_cnt = s->virtual_disk_size >> s->block_size_bits;
if (s->virtual_disk_size - (data_blocks_cnt << s->block_size_bits)) {
data_blocks_cnt++;
}
bitmap_blocks_cnt = data_blocks_cnt >> s->chunk_ratio_bits;
if (data_blocks_cnt - (bitmap_blocks_cnt << s->chunk_ratio_bits)) {
bitmap_blocks_cnt++;
}
data_blocks_cnt = DIV_ROUND_UP(s->virtual_disk_size, s->block_size);
bitmap_blocks_cnt = DIV_ROUND_UP(data_blocks_cnt, s->chunk_ratio);
if (s->parent_entries) {
s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1);