diff options
author | Kevin Wolf <kwolf@redhat.com> | 2019-03-11 16:13:16 +0100 |
---|---|---|
committer | Kevin Wolf <kwolf@redhat.com> | 2019-03-12 20:30:14 +0100 |
commit | 30855137783c0c762007044821a6f11e14e6af33 (patch) | |
tree | d30b921270e23e1d0852e0c18533c7967be4add6 | |
parent | 69b736e76567ecbc9b9e55570bc0afc840614a98 (diff) | |
download | qemu-30855137783c0c762007044821a6f11e14e6af33.zip qemu-30855137783c0c762007044821a6f11e14e6af33.tar.gz qemu-30855137783c0c762007044821a6f11e14e6af33.tar.bz2 |
file-posix: Fix bdrv_open_flags() for snapshot=on
Using a different read-only setting for bs->open_flags than for the
flags to the driver's open function is just inconsistent and a bad idea.
After this patch, the temporary snapshot keeps being opened read-only if
read-only=on,snapshot=on is passed.
If we wanted to change this behaviour to make only the orginal image
file read-only, but the temporary overlay read-write (as the comment in
the removed code suggests), that change would have to be made in
bdrv_temp_snapshot_options() (where the comment suggests otherwise).
Addressing this inconsistency before introducing dynamic auto-read-only
is important because otherwise we would immediately try to reopen the
temporary overlay even though the file is already unlinked.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r-- | block.c | 7 | ||||
-rwxr-xr-x | tests/qemu-iotests/051 | 7 | ||||
-rw-r--r-- | tests/qemu-iotests/051.out | 9 | ||||
-rw-r--r-- | tests/qemu-iotests/051.pc.out | 9 |
4 files changed, 25 insertions, 7 deletions
@@ -1163,13 +1163,6 @@ static int bdrv_open_flags(BlockDriverState *bs, int flags) */ open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_PROTOCOL); - /* - * Snapshots should be writable. - */ - if (flags & BDRV_O_TEMPORARY) { - open_flags |= BDRV_O_RDWR; - } - return open_flags; } diff --git a/tests/qemu-iotests/051 b/tests/qemu-iotests/051 index 3b50c7f..6a3b7c2 100755 --- a/tests/qemu-iotests/051 +++ b/tests/qemu-iotests/051 @@ -356,6 +356,13 @@ $QEMU_IO -c "read -P 0x33 0 4k" "$TEST_IMG" | _filter_qemu_io # Using snapshot=on with a non-existent TMPDIR TMPDIR=/nonexistent run_qemu -drive driver=null-co,snapshot=on +# Using snapshot=on together with read-only=on +echo "info block" | + run_qemu -drive file="$TEST_IMG",snapshot=on,read-only=on,if=none,id=$device_id | + _filter_qemu_io | + sed -e 's#"/[^"]*/vl\.[A-Za-z0-9]\{6\}"#SNAPSHOT_PATH#g' + + # success, all done echo "*** done" rm -f $seq.full diff --git a/tests/qemu-iotests/051.out b/tests/qemu-iotests/051.out index b900935..9f1cf22 100644 --- a/tests/qemu-iotests/051.out +++ b/tests/qemu-iotests/051.out @@ -458,4 +458,13 @@ read 4096/4096 bytes at offset 0 Testing: -drive driver=null-co,snapshot=on QEMU_PROG: -drive driver=null-co,snapshot=on: Could not get temporary filename: No such file or directory +Testing: -drive file=TEST_DIR/t.qcow2,snapshot=on,read-only=on,if=none,id=drive0 +QEMU X.Y.Z monitor - type 'help' for more information +(qemu) info block +drive0 (NODE_NAME): json:{"backing": {"driver": "qcow2", "file": {"driver": "file", "filename": "TEST_DIR/t.qcow2"}}, "driver": "qcow2", "file": {"driver": "file", "filename": SNAPSHOT_PATH}} (qcow2, read-only) + Removable device: not locked, tray closed + Cache mode: writeback, ignore flushes + Backing file: TEST_DIR/t.qcow2 (chain depth: 1) +(qemu) quit + *** done diff --git a/tests/qemu-iotests/051.pc.out b/tests/qemu-iotests/051.pc.out index 8c5c735..c4743cc 100644 --- a/tests/qemu-iotests/051.pc.out +++ b/tests/qemu-iotests/051.pc.out @@ -530,4 +530,13 @@ read 4096/4096 bytes at offset 0 Testing: -drive driver=null-co,snapshot=on QEMU_PROG: -drive driver=null-co,snapshot=on: Could not get temporary filename: No such file or directory +Testing: -drive file=TEST_DIR/t.qcow2,snapshot=on,read-only=on,if=none,id=drive0 +QEMU X.Y.Z monitor - type 'help' for more information +(qemu) info block +drive0 (NODE_NAME): json:{"backing": {"driver": "qcow2", "file": {"driver": "file", "filename": "TEST_DIR/t.qcow2"}}, "driver": "qcow2", "file": {"driver": "file", "filename": SNAPSHOT_PATH}} (qcow2, read-only) + Removable device: not locked, tray closed + Cache mode: writeback, ignore flushes + Backing file: TEST_DIR/t.qcow2 (chain depth: 1) +(qemu) quit + *** done |