block: Attach bs->file only during .bdrv_open()
The way that attaching bs->file worked was a bit unusual in that it was
the only child that would be attached to a node which is not opened yet.
Because of this, the block layer couldn't know yet which permissions the
driver would eventually need.
This patch moves the point where bs->file is attached to the beginning
of the individual .bdrv_open() implementations, so drivers already know
what they are going to do with the child. This is also more consistent
with how driver-specific children work.
For a moment, bdrv_open() gets its own BdrvChild to perform image
probing, but instead of directly assigning this BdrvChild to the BDS, it
becomes a temporary one and the node name is passed as an option to the
drivers, so that they can simply use bdrv_open_child() to create another
reference for their own use.
This duplicated child for (the not opened yet) bs is not the final
state, a follow-up patch will change the image probing code to use a
BlockBackend, which is completely independent of bs.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
diff --git a/block/bochs.c b/block/bochs.c
index 8c9652e..7dd2ac4 100644
--- a/block/bochs.c
+++ b/block/bochs.c
@@ -104,6 +104,12 @@
struct bochs_header bochs;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
bs->read_only = true; /* no write support yet */
ret = bdrv_pread(bs->file, 0, &bochs, sizeof(bochs));
diff --git a/block/cloop.c b/block/cloop.c
index 7b75f7e..877c9b0 100644
--- a/block/cloop.c
+++ b/block/cloop.c
@@ -66,6 +66,12 @@
uint32_t offsets_size, max_compressed_block_size = 1, i;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
bs->read_only = true;
/* read header */
diff --git a/block/crypto.c b/block/crypto.c
index e05e4dd..7cb2ff2 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -300,6 +300,12 @@
QCryptoBlockOpenOptions *open_opts = NULL;
unsigned int cflags = 0;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
opts = qemu_opts_create(opts_spec, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
diff --git a/block/dmg.c b/block/dmg.c
index 58a3ae8..8e387cd 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -413,6 +413,12 @@
int64_t offset;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
block_module_load_one("dmg-bz2");
bs->read_only = true;
diff --git a/block/parallels.c b/block/parallels.c
index ac94dfb..b2ec09f 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -581,6 +581,12 @@
Error *local_err = NULL;
char *buf;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
if (ret < 0) {
goto fail;
diff --git a/block/qcow.c b/block/qcow.c
index 4534515..038b05a 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -106,6 +106,12 @@
QCowHeader header;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
goto fail;
diff --git a/block/qcow2.c b/block/qcow2.c
index 3e1172b..21e6142 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -814,8 +814,8 @@
return ret;
}
-static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
- Error **errp)
+static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
{
BDRVQcow2State *s = bs->opaque;
unsigned int len, i;
@@ -1205,6 +1205,18 @@
return ret;
}
+static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
+ return qcow2_do_open(bs, options, flags, errp);
+}
+
static void qcow2_refresh_limits(BlockDriverState *bs, Error **errp)
{
BDRVQcow2State *s = bs->opaque;
@@ -1785,7 +1797,7 @@
options = qdict_clone_shallow(bs->options);
flags &= ~BDRV_O_INACTIVE;
- ret = qcow2_open(bs, options, flags, &local_err);
+ ret = qcow2_do_open(bs, options, flags, &local_err);
QDECREF(options);
if (local_err) {
error_propagate(errp, local_err);
diff --git a/block/qed.c b/block/qed.c
index 0b62c77..62a0a09 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -415,8 +415,8 @@
}
}
-static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
- Error **errp)
+static int bdrv_qed_do_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
{
BDRVQEDState *s = bs->opaque;
QEDHeader le_header;
@@ -550,6 +550,18 @@
return ret;
}
+static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
+ return bdrv_qed_do_open(bs, options, flags, errp);
+}
+
static void bdrv_qed_refresh_limits(BlockDriverState *bs, Error **errp)
{
BDRVQEDState *s = bs->opaque;
@@ -1629,7 +1641,7 @@
bdrv_qed_close(bs);
memset(s, 0, sizeof(BDRVQEDState));
- ret = bdrv_qed_open(bs, NULL, bs->open_flags, &local_err);
+ ret = bdrv_qed_do_open(bs, NULL, bs->open_flags, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_prepend(errp, "Could not reopen qed layer: ");
diff --git a/block/raw-format.c b/block/raw-format.c
index 0ddffbd..ce34d1b 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -384,6 +384,12 @@
BDRVRawState *s = bs->opaque;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
bs->sg = bs->file->bs->sg;
bs->supported_write_flags = BDRV_REQ_FUA &
bs->file->bs->supported_write_flags;
diff --git a/block/replication.c b/block/replication.c
index 729dd12..eff85c7 100644
--- a/block/replication.c
+++ b/block/replication.c
@@ -86,6 +86,12 @@
const char *mode;
const char *top_id;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
ret = -EINVAL;
opts = qemu_opts_create(&replication_runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
diff --git a/block/vdi.c b/block/vdi.c
index 0aeb940..18b4773 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -363,6 +363,12 @@
int ret;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
logout("\n");
ret = bdrv_read(bs->file, 0, (uint8_t *)&header, 1);
diff --git a/block/vhdx.c b/block/vhdx.c
index c67772e..9918ee9 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -898,6 +898,12 @@
uint64_t signature;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
s->bat = NULL;
s->first_visible_write = true;
diff --git a/block/vmdk.c b/block/vmdk.c
index 393c84d..9d68ec5 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -943,6 +943,12 @@
uint32_t magic;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
buf = vmdk_read_desc(bs->file, 0, errp);
if (!buf) {
return -EINVAL;
diff --git a/block/vpc.c b/block/vpc.c
index ed6353d..d0df2a1 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -220,6 +220,12 @@
int disk_type = VHD_DYNAMIC;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
opts = qemu_opts_create(&vpc_runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
