qcow2: Add offset_to_l2_slice_index()

Similar to offset_to_l2_index(), this function takes a guest offset
and returns the index in the L2 slice that contains its L2 entry.

An L2 slice has currently the same size as an L2 table (one cluster),
so both functions return the same value for now.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: a1c45c5c5a76146dd1712d8d1e7b409ad539c718.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Alberto Garcia 2018-02-05 16:33:14 +02:00 committed by Max Reitz
parent 3c2e511a24
commit 8f81817577
1 changed files with 5 additions and 0 deletions

View File

@ -474,6 +474,11 @@ static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
return (offset >> s->cluster_bits) & (s->l2_size - 1);
}
static inline int offset_to_l2_slice_index(BDRVQcow2State *s, int64_t offset)
{
return (offset >> s->cluster_bits) & (s->l2_slice_size - 1);
}
static inline int64_t align_offset(int64_t offset, int n)
{
offset = (offset + n - 1) & ~(n - 1);