From d5b23994586934f18853684307bc01965bcdad4b Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Tue, 22 Jun 2021 16:00:30 +0200 Subject: [PATCH] block: BDRV_O_NO_IO for backing file on creation When creating an image file with a backing file, we generally try to open the backing file (unless -u was specified), mostly to verify that it is there, but also to get the file size if none was specified for the new image. For neither of these things do we need data I/O, and so we can pass BDRV_O_NO_IO when opening the backing file. This allows us to open even encrypted backing images without requiring the user to provide a secret. This makes the -u switch in iotests 189 and 198 unnecessary (and the $size parameter), so drop it, because this way we get regression tests for this patch here. Fixes: https://gitlab.com/qemu-project/qemu/-/issues/441 Signed-off-by: Max Reitz Message-Id: <20210622140030.212487-1-mreitz@redhat.com> Signed-off-by: Kevin Wolf --- block.c | 6 +++++- tests/qemu-iotests/189 | 2 +- tests/qemu-iotests/198 | 2 +- 3 files changed, 7 insertions(+), 3 deletions(-) diff --git a/block.c b/block.c index 3e277855e7..a2a4a0dd80 100644 --- a/block.c +++ b/block.c @@ -6553,9 +6553,13 @@ void bdrv_img_create(const char *filename, const char *fmt, } assert(full_backing); - /* backing files always opened read-only */ + /* + * No need to do I/O here, which allows us to open encrypted + * backing images without needing the secret + */ back_flags = flags; back_flags &= ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); + back_flags |= BDRV_O_NO_IO; backing_options = qdict_new(); if (backing_fmt) { diff --git a/tests/qemu-iotests/189 b/tests/qemu-iotests/189 index 4e463385b2..801494c6b9 100755 --- a/tests/qemu-iotests/189 +++ b/tests/qemu-iotests/189 @@ -67,7 +67,7 @@ echo "== verify pattern ==" $QEMU_IO --object $SECRET0 -c "read -P 0xa 0 $size" --image-opts $IMGSPECBASE | _filter_qemu_io | _filter_testdir echo "== create overlay ==" -_make_test_img --object $SECRET1 -o "encrypt.format=luks,encrypt.key-secret=sec1,encrypt.iter-time=10" -u -b "$TEST_IMG_BASE" -F $IMGFMT $size +_make_test_img --object $SECRET1 -o "encrypt.format=luks,encrypt.key-secret=sec1,encrypt.iter-time=10" -b "$TEST_IMG_BASE" -F $IMGFMT echo echo "== writing part of a cluster ==" diff --git a/tests/qemu-iotests/198 b/tests/qemu-iotests/198 index b333a8f281..1c93dea1f7 100755 --- a/tests/qemu-iotests/198 +++ b/tests/qemu-iotests/198 @@ -64,7 +64,7 @@ echo "== writing whole image base ==" $QEMU_IO --object $SECRET0 -c "write -P 0xa 0 $size" --image-opts $IMGSPECBASE | _filter_qemu_io | _filter_testdir echo "== create overlay ==" -_make_test_img --object $SECRET1 -o "encrypt.format=luks,encrypt.key-secret=sec1,encrypt.iter-time=10" -u -b "$TEST_IMG_BASE" -F $IMGFMT $size +_make_test_img --object $SECRET1 -o "encrypt.format=luks,encrypt.key-secret=sec1,encrypt.iter-time=10" -b "$TEST_IMG_BASE" -F $IMGFMT echo echo "== writing whole image layer ==" -- 2.11.0