This commit tries to clarify few function arguments,
and add comments describing the encrypt/decrypt interface
Signed-off-by: Maxim Levitsky <mlevi...@redhat.com>
---
block/qcow2-cluster.c | 8 +++----
block/qcow2-threads.c | 53 ++++++++++++++++++++++++++++++++++---------
2 files changed, 46 insertions(+), 15 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index f09cc992af..b95e64c237 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -463,8 +463,8 @@ static int coroutine_fn
do_perform_cow_read(BlockDriverState *bs,
}
static bool coroutine_fn do_perform_cow_encrypt(BlockDriverState *bs,
- uint64_t src_cluster_offset,
- uint64_t cluster_offset,
+ uint64_t guest_cluster_offset,
+ uint64_t host_cluster_offset,
unsigned offset_in_cluster,
uint8_t *buffer,
unsigned bytes)
@@ -474,8 +474,8 @@ static bool coroutine_fn
do_perform_cow_encrypt(BlockDriverState *bs,
assert((offset_in_cluster & ~BDRV_SECTOR_MASK) == 0);
assert((bytes & ~BDRV_SECTOR_MASK) == 0);
assert(s->crypto);
- if (qcow2_co_encrypt(bs, cluster_offset,
- src_cluster_offset + offset_in_cluster,
+ if (qcow2_co_encrypt(bs, host_cluster_offset,
+ guest_cluster_offset + offset_in_cluster,
buffer, bytes) < 0) {
return false;
}
diff --git a/block/qcow2-threads.c b/block/qcow2-threads.c
index 3b1e63fe41..8bc339690f 100644
--- a/block/qcow2-threads.c
+++ b/block/qcow2-threads.c
@@ -234,15 +234,19 @@ static int qcow2_encdec_pool_func(void *opaque)
}
static int coroutine_fn
-qcow2_co_encdec(BlockDriverState *bs, uint64_t file_cluster_offset,
- uint64_t offset, void *buf, size_t len, Qcow2EncDecFunc func)
+qcow2_co_encdec(BlockDriverState *bs, uint64_t host_cluster_offset,
+ uint64_t guest_offset, void *buf, size_t len,
+ Qcow2EncDecFunc func)
{
BDRVQcow2State *s = bs->opaque;
+
+ uint64_t offset = s->crypt_physical_offset ?
+ host_cluster_offset + offset_into_cluster(s, guest_offset) :
+ guest_offset;
+
Qcow2EncDecData arg = {
.block = s->crypto,
- .offset = s->crypt_physical_offset ?
- file_cluster_offset + offset_into_cluster(s, offset) :
- offset,
+ .offset = offset,
.buf = buf,
.len = len,
.func = func,
@@ -251,18 +255,45 @@ qcow2_co_encdec(BlockDriverState *bs, uint64_t
file_cluster_offset,
return qcow2_co_process(bs, qcow2_encdec_pool_func, &arg);
}
+
+/*
+ * qcow2_co_encrypt()
+ *
+ * Encrypts a sector size aligned contiguous area
+ *
+ * @host_cluster_offset - on disk offset of the cluster in which
+ * the buffer resides
+ *
+ * @guest_offset - guest (virtual) offset of the buffer
+ * @buf - buffer with the data to encrypt
+ * @len - length of the buffer
+ *
+ * Note that the area is not cluster aligned and might cross a cluster
+ * boundary
+ *
+ *
+ */
int coroutine_fn
-qcow2_co_encrypt(BlockDriverState *bs, uint64_t file_cluster_offset,
- uint64_t offset, void *buf, size_t len)
+qcow2_co_encrypt(BlockDriverState *bs, uint64_t host_cluster_offset,
+ uint64_t guest_offset, void *buf, size_t len)
{
- return qcow2_co_encdec(bs, file_cluster_offset, offset, buf, len,
+ return qcow2_co_encdec(bs, host_cluster_offset, guest_offset, buf, len,
qcrypto_block_encrypt);
}
+
+/*
+ * qcow2_co_decrypt()
+ *
+ * Decrypts a sector size aligned contiguous area
+ * Same function as qcow2_co_encrypt
+ *
+ */
+
int coroutine_fn
-qcow2_co_decrypt(BlockDriverState *bs, uint64_t file_cluster_offset,
- uint64_t offset, void *buf, size_t len)
+qcow2_co_decrypt(BlockDriverState *bs, uint64_t host_cluster_offset,
+ uint64_t guest_offset, void *buf, size_t len)
{
- return qcow2_co_encdec(bs, file_cluster_offset, offset, buf, len,
+ return qcow2_co_encdec(bs, host_cluster_offset, guest_offset, buf, len,
qcrypto_block_decrypt);
}
--
2.17.2
