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-rw-r--r--block.c144
1 files changed, 100 insertions, 44 deletions
diff --git a/block.c b/block.c
index 5e80336e9f..d088ee02ff 100644
--- a/block.c
+++ b/block.c
@@ -1102,12 +1102,46 @@ static int bdrv_fill_options(QDict **options, const char **pfilename,
return 0;
}
+static BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
+ BlockDriverState *child_bs,
+ const BdrvChildRole *child_role)
+{
+ BdrvChild *child = g_new(BdrvChild, 1);
+ *child = (BdrvChild) {
+ .bs = child_bs,
+ .role = child_role,
+ };
+
+ QLIST_INSERT_HEAD(&parent_bs->children, child, next);
+
+ return child;
+}
+
+static void bdrv_detach_child(BdrvChild *child)
+{
+ QLIST_REMOVE(child, next);
+ g_free(child);
+}
+
+void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child)
+{
+ BlockDriverState *child_bs = child->bs;
+
+ if (child->bs->inherits_from == parent) {
+ child->bs->inherits_from = NULL;
+ }
+
+ bdrv_detach_child(child);
+ bdrv_unref(child_bs);
+}
+
void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
{
if (bs->backing_hd) {
assert(bs->backing_blocker);
bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
+ bdrv_detach_child(bs->backing_child);
} else if (backing_hd) {
error_setg(&bs->backing_blocker,
"node is used as backing hd of '%s'",
@@ -1118,8 +1152,10 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
if (!backing_hd) {
error_free(bs->backing_blocker);
bs->backing_blocker = NULL;
+ bs->backing_child = NULL;
goto out;
}
+ bs->backing_child = bdrv_attach_child(bs, backing_hd, &child_backing);
bs->open_flags &= ~BDRV_O_NO_BACKING;
pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
pstrcpy(bs->backing_format, sizeof(bs->backing_format),
@@ -1202,6 +1238,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
error_free(local_err);
goto free_exit;
}
+
bdrv_set_backing_hd(bs, backing_hd);
free_exit:
@@ -1214,7 +1251,7 @@ free_exit:
* device's options.
*
* If allow_none is true, no image will be opened if filename is false and no
- * BlockdevRef is given. *pbs will remain unchanged and 0 will be returned.
+ * BlockdevRef is given. NULL will be returned, but errp remains unset.
*
* bdrev_key specifies the key for the image's BlockdevRef in the options QDict.
* That QDict has to be flattened; therefore, if the BlockdevRef is a QDict
@@ -1222,21 +1259,21 @@ free_exit:
* BlockdevRef.
*
* The BlockdevRef will be removed from the options QDict.
- *
- * 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,
- BlockDriverState* parent, const BdrvChildRole *child_role,
- bool allow_none, Error **errp)
+BdrvChild *bdrv_open_child(const char *filename,
+ QDict *options, const char *bdref_key,
+ BlockDriverState* parent,
+ const BdrvChildRole *child_role,
+ bool allow_none, Error **errp)
{
+ BdrvChild *c = NULL;
+ BlockDriverState *bs;
QDict *image_options;
int ret;
char *bdref_key_dot;
const char *reference;
- assert(pbs);
- assert(*pbs == NULL);
+ assert(child_role != NULL);
bdref_key_dot = g_strdup_printf("%s.", bdref_key);
qdict_extract_subqdict(options, &image_options, bdref_key_dot);
@@ -1244,23 +1281,60 @@ int bdrv_open_image(BlockDriverState **pbs, const char *filename,
reference = qdict_get_try_str(options, bdref_key);
if (!filename && !reference && !qdict_size(image_options)) {
- if (allow_none) {
- ret = 0;
- } else {
+ if (!allow_none) {
error_setg(errp, "A block device must be specified for \"%s\"",
bdref_key);
- ret = -EINVAL;
}
QDECREF(image_options);
goto done;
}
- ret = bdrv_open_inherit(pbs, filename, reference, image_options, 0,
+ bs = NULL;
+ ret = bdrv_open_inherit(&bs, filename, reference, image_options, 0,
parent, child_role, NULL, errp);
+ if (ret < 0) {
+ goto done;
+ }
+
+ c = bdrv_attach_child(parent, bs, child_role);
done:
qdict_del(options, bdref_key);
- return ret;
+ return c;
+}
+
+/*
+ * This is a version of bdrv_open_child() that returns 0/-EINVAL instead of
+ * a BdrvChild object.
+ *
+ * If allow_none is true, no image will be opened if filename is false and no
+ * BlockdevRef is given. *pbs will remain unchanged and 0 will be returned.
+ *
+ * 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,
+ BlockDriverState* parent, const BdrvChildRole *child_role,
+ bool allow_none, Error **errp)
+{
+ Error *local_err = NULL;
+ BdrvChild *c;
+
+ assert(pbs);
+ assert(*pbs == NULL);
+
+ c = bdrv_open_child(filename, options, bdref_key, parent, child_role,
+ allow_none, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return -EINVAL;
+ }
+
+ if (c != NULL) {
+ *pbs = c->bs;
+ }
+
+ return 0;
}
int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp)
@@ -1328,19 +1402,6 @@ out:
return ret;
}
-static void bdrv_attach_child(BlockDriverState *parent_bs,
- BlockDriverState *child_bs,
- const BdrvChildRole *child_role)
-{
- BdrvChild *child = g_new(BdrvChild, 1);
- *child = (BdrvChild) {
- .bs = child_bs,
- .role = child_role,
- };
-
- QLIST_INSERT_HEAD(&parent_bs->children, child, next);
-}
-
/*
* Opens a disk image (raw, qcow2, vmdk, ...)
*
@@ -1393,9 +1454,6 @@ static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename,
return -ENODEV;
}
bdrv_ref(bs);
- if (child_role) {
- bdrv_attach_child(parent, bs, child_role);
- }
*pbs = bs;
return 0;
}
@@ -1540,10 +1598,6 @@ static int bdrv_open_inherit(BlockDriverState **pbs, const char *filename,
goto close_and_fail;
}
- if (child_role) {
- bdrv_attach_child(parent, bs, child_role);
- }
-
QDECREF(options);
*pbs = bs;
return 0;
@@ -1849,20 +1903,23 @@ void bdrv_close(BlockDriverState *bs)
if (bs->drv) {
BdrvChild *child, *next;
- QLIST_FOREACH_SAFE(child, &bs->children, next, next) {
- if (child->bs->inherits_from == bs) {
- child->bs->inherits_from = NULL;
- }
- QLIST_REMOVE(child, next);
- g_free(child);
- }
+ bs->drv->bdrv_close(bs);
if (bs->backing_hd) {
BlockDriverState *backing_hd = bs->backing_hd;
bdrv_set_backing_hd(bs, NULL);
bdrv_unref(backing_hd);
}
- bs->drv->bdrv_close(bs);
+
+ QLIST_FOREACH_SAFE(child, &bs->children, next, next) {
+ /* TODO Remove bdrv_unref() from drivers' close function and use
+ * bdrv_unref_child() here */
+ if (child->bs->inherits_from == bs) {
+ child->bs->inherits_from = NULL;
+ }
+ bdrv_detach_child(child);
+ }
+
g_free(bs->opaque);
bs->opaque = NULL;
bs->drv = NULL;
@@ -2116,7 +2173,6 @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
/* The contents of 'tmp' will become bs_top, as we are
* swapping bs_new and bs_top contents. */
bdrv_set_backing_hd(bs_top, bs_new);
- bdrv_attach_child(bs_top, bs_new, &child_backing);
}
static void bdrv_delete(BlockDriverState *bs)
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2025-04-30 05:53:35 +0200