Factor out read/write extent code, since there will be more things to
take care of once reading/writing compressed clusters is introduced.
Signed-off-by: Fam Zheng <famc...@gmail.com>
---
block/vmdk.c | 54 +++++++++++++++++++++++++++++++++++++++++++++---------
1 files changed, 45 insertions(+), 9 deletions(-)
diff --git a/block/vmdk.c b/block/vmdk.c
index 9d1ae32..0d989f6 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -829,6 +829,43 @@ static int vmdk_is_allocated(BlockDriverState *bs, int64_t
sector_num,
return ret;
}
+static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset,
+ int64_t offset_in_cluster, const uint8_t *buf,
+ int nb_sectors, int64_t sector_num)
+{
+ int ret;
+ const uint8_t *write_buf = buf;
+ int write_len = nb_sectors * 512;
+
+ ret = bdrv_pwrite(extent->file,
+ cluster_offset + offset_in_cluster,
+ write_buf,
+ write_len);
+ if (ret != write_len) {
+ ret = ret < 0 ? ret : -EIO;
+ goto out;
+ }
+ ret = 0;
+ out:
+ return ret;
+}
+
+static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset,
+ int64_t offset_in_cluster, uint8_t *buf,
+ int nb_sectors)
+{
+ int ret;
+
+ ret = bdrv_pread(extent->file,
+ cluster_offset + offset_in_cluster,
+ buf, nb_sectors * 512);
+ if (ret == nb_sectors * 512) {
+ return 0;
+ } else {
+ return -EIO;
+ }
+}
+
static int vmdk_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
@@ -865,10 +902,10 @@ static int vmdk_read(BlockDriverState *bs, int64_t
sector_num,
memset(buf, 0, 512 * n);
}
} else {
- ret = bdrv_pread(extent->file,
- cluster_offset + index_in_cluster * 512,
- buf, n * 512);
- if (ret < 0) {
+ ret = vmdk_read_extent(extent,
+ cluster_offset, index_in_cluster * 512,
+ buf, n);
+ if (ret) {
return ret;
}
}
@@ -917,11 +954,10 @@ static int vmdk_write(BlockDriverState *bs, int64_t
sector_num,
n = nb_sectors;
}
- ret = bdrv_pwrite(extent->file,
- cluster_offset + index_in_cluster * 512,
- buf,
- n * 512);
- if (ret < 0) {
+ ret = vmdk_write_extent(extent,
+ cluster_offset, index_in_cluster * 512,
+ buf, n, sector_num);
+ if (ret) {
return ret;
}
if (m_data.valid) {
