Instead of letting every caller of bdrv_open() determine the right flags
for its child node manually and pass them to the function, pass the
parent node and the role of the newly opened child (like backing file,
protocol layer, etc.).
Signed-off-by: Kevin Wolf <address@hidden>
---
block.c | 74 ++++++++++++++++++++++++++++++++++++++---------
block/blkdebug.c | 2 +-
block/blkverify.c | 4 +--
block/quorum.c | 4 +--
block/vmdk.c | 5 ++--
include/block/block.h | 4 ++-
include/block/block_int.h | 7 +++++
7 files changed, 78 insertions(+), 22 deletions(-)
diff --git a/block.c b/block.c
index cea022f..c4f0fb4 100644
--- a/block.c
+++ b/block.c
@@ -79,6 +79,12 @@ static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states =
static QLIST_HEAD(, BlockDriver) bdrv_drivers =
QLIST_HEAD_INITIALIZER(bdrv_drivers);
+static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename,
+ const char *reference, QDict *options, int flags,
+ BlockDriverState* parent,
+ const BdrvChildRole *child_role,
+ BlockDriver *drv, Error **errp);
+
static void bdrv_dirty_bitmap_truncate(BlockDriverState *bs);
/* If non-zero, use only whitelisted block drivers */
static int use_bdrv_whitelist;
@@ -672,8 +678,8 @@ static int bdrv_temp_snapshot_flags(int flags)
}
/*
- * Returns the flags that bs->file should get, based on the given flags for
- * the parent BDS
+ * Returns the flags that bs->file should get if a protocol driver is expected,
+ * based on the given flags for the parent BDS
*/
static int bdrv_inherited_flags(int flags)
{
@@ -690,6 +696,25 @@ static int bdrv_inherited_flags(int flags)
return flags;
}
+const BdrvChildRole child_file = {
+ .inherit_flags = bdrv_inherited_flags,
+};
+
+/*
+ * Returns the flags that bs->file should get if the use of formats (and not
+ * only protocols) is permitted for it, based on the given flags for the parent
+ * BDS
+ */
+static int bdrv_inherited_fmt_flags(int parent_flags)
+{
+ int flags = child_file.inherit_flags(parent_flags);
+ return flags & ~BDRV_O_PROTOCOL;
+}
+
+const BdrvChildRole child_format = {
+ .inherit_flags = bdrv_inherited_fmt_flags,
+};
+
/*
* Returns the flags that bs->backing_hd should get, based on the given flags
* for the parent BDS
@@ -705,6 +730,10 @@ static int bdrv_backing_flags(int flags)
return flags;
}
+static const BdrvChildRole child_backing = {
+ .inherit_flags = bdrv_backing_flags,
+};
+
static int bdrv_open_flags(BlockDriverState *bs, int flags)
{
int open_flags = flags | BDRV_O_CACHE_WB;
@@ -827,7 +856,6 @@ static int bdrv_open_common(BlockDriverState *bs,
BlockDriverState *file,
return 0;
}
- bs->open_flags = flags;
bs->guest_block_size = 512;
bs->request_alignment = 512;
bs->zero_beyond_eof = true;
@@ -1134,9 +1162,10 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict
*options, Error **errp)
}
assert(bs->backing_hd == NULL);
- ret = bdrv_open(&backing_hd,
- *backing_filename ? backing_filename : NULL, NULL, options,
- bdrv_backing_flags(bs->open_flags), NULL, &local_err);
+ ret = bdrv_open_inherit(&backing_hd,
+ *backing_filename ? backing_filename : NULL,
+ NULL, options, 0, bs, &child_backing,
+ NULL, &local_err);
if (ret < 0) {
bdrv_unref(backing_hd);
backing_hd = NULL;
@@ -1170,7 +1199,8 @@ free_exit:
* To conform with the behavior of bdrv_open(), *pbs has to be NULL.
*/
int bdrv_open_image(BlockDriverState **pbs, const char *filename,
- QDict *options, const char *bdref_key, int flags,
+ QDict *options, const char *bdref_key,
+ BlockDriverState* parent, const BdrvChildRole *child_role,
bool allow_none, Error **errp)
{
QDict *image_options;
@@ -1198,7 +1228,8 @@ int bdrv_open_image(BlockDriverState **pbs, const char
*filename,
goto done;
}
- ret = bdrv_open(pbs, filename, reference, image_options, flags, NULL, errp);
+ ret = bdrv_open_inherit(pbs, filename, reference, image_options, 0,
+ parent, child_role, NULL, errp);
done:
qdict_del(options, bdref_key);
@@ -1285,9 +1316,11 @@ out:
* should be opened. If specified, neither options nor a filename may be
given,
* nor can an existing BDS be reused (that is, *pbs has to be NULL).
*/
-int bdrv_open(BlockDriverState **pbs, const char *filename,
- const char *reference, QDict *options, int flags,
- BlockDriver *drv, Error **errp)
+static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename,
+ const char *reference, QDict *options, int flags,
+ BlockDriverState* parent,