block: Fail gracefully with missing filename

This fixes a regression introduced in commit 2a05cbe42 ('block: Allow
block devices without files'):

$ qemu-system-x86_64 -drive driver=file
qemu-system-x86_64: block.c:892: bdrv_open_common: Assertion
`!drv->bdrv_needs_filename || filename != ((void *)0)' failed.

Now the respective check must be performed not only in bdrv_file_open(),
but also in bdrv_open().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

2 files changed, 36 insertions, 0 deletions

diff --git a/tests/qemu-iotests/051 b/tests/qemu-iotests/051
index b23d91b6f0..46345fb155 100755
--- a/tests/qemu-iotests/051
+++ b/tests/qemu-iotests/051
@@ -172,6 +172,18 @@ run_qemu -drive file="$TEST_IMG",file.driver=file
 run_qemu -drive file="$TEST_IMG",file.driver=qcow2
 
 echo
+echo === Leaving out required options ===
+echo
+
+run_qemu -drive driver=file
+run_qemu -drive driver=nbd
+run_qemu -drive driver=raw
+run_qemu -drive file.driver=file
+run_qemu -drive file.driver=nbd
+run_qemu -drive file.driver=raw
+run_qemu -drive foo=bar
+
+echo
 echo === Parsing protocol from file name ===
 echo
 
diff --git a/tests/qemu-iotests/051.out b/tests/qemu-iotests/051.out
index d0c5173626..30e2dbd6d7 100644
--- a/tests/qemu-iotests/051.out
+++ b/tests/qemu-iotests/051.out
@@ -225,6 +225,30 @@ Testing: -drive file=TEST_DIR/t.qcow2,file.driver=qcow2
 QEMU_PROG: -drive file=TEST_DIR/t.qcow2,file.driver=qcow2: could not open disk image TEST_DIR/t.qcow2: Block format 'qcow2' used by device '' doesn't support the option 'filename'
 
 
+=== Leaving out required options ===
+
+Testing: -drive driver=file
+QEMU_PROG: -drive driver=file: could not open disk image ide0-hd0: The 'file' block driver requires a file name
+
+Testing: -drive driver=nbd
+QEMU_PROG: -drive driver=nbd: could not open disk image ide0-hd0: Could not open image: Invalid argument
+
+Testing: -drive driver=raw
+QEMU_PROG: -drive driver=raw: could not open disk image ide0-hd0: Can't use 'raw' as a block driver for the protocol level
+
+Testing: -drive file.driver=file
+QEMU_PROG: -drive file.driver=file: could not open disk image ide0-hd0: The 'file' block driver requires a file name
+
+Testing: -drive file.driver=nbd
+QEMU_PROG: -drive file.driver=nbd: could not open disk image ide0-hd0: Could not open image: Invalid argument
+
+Testing: -drive file.driver=raw
+QEMU_PROG: -drive file.driver=raw: could not open disk image ide0-hd0: Can't use 'raw' as a block driver for the protocol level
+
+Testing: -drive foo=bar
+QEMU_PROG: -drive foo=bar: could not open disk image ide0-hd0: Must specify either driver or file
+
+
 === Parsing protocol from file name ===
 
 Testing: -hda foo:bar