qcow2: Refactor get_cluster_table()

After the previous patch we're now always using l2_load() in
get_cluster_table() regardless of whether a new L2 table has to be
allocated or not.

This patch refactors that part of the code to use one single l2_load()
call.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: ce31758c4a1fadccea7a6ccb93951eb01d95fd4c.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Alberto Garcia 2018-02-05 16:33:18 +02:00 committed by Max Reitz
parent 3861946a5b
commit 05f9ee4689

View file

@ -694,15 +694,7 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
return -EIO;
}
/* seek the l2 table of the given l2 offset */
if (s->l1_table[l1_index] & QCOW_OFLAG_COPIED) {
/* load the l2 table in memory */
ret = l2_load(bs, offset, l2_offset, &l2_table);
if (ret < 0) {
return ret;
}
} else {
if (!(s->l1_table[l1_index] & QCOW_OFLAG_COPIED)) {
/* First allocate a new L2 table (and do COW if needed) */
ret = l2_allocate(bs, l1_index);
if (ret < 0) {
@ -718,11 +710,12 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
/* Get the offset of the newly-allocated l2 table */
l2_offset = s->l1_table[l1_index] & L1E_OFFSET_MASK;
assert(offset_into_cluster(s, l2_offset) == 0);
/* Load the l2 table in memory */
ret = l2_load(bs, offset, l2_offset, &l2_table);
if (ret < 0) {
return ret;
}
}
/* load the l2 table in memory */
ret = l2_load(bs, offset, l2_offset, &l2_table);
if (ret < 0) {
return ret;
}
/* find the cluster offset for the given disk offset */