From 820c6bee534ec3bd61c7d14d7040ec917cc25ab2 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Sat, 6 Jun 2020 11:18:06 +0300 Subject: [PATCH] qcow2_format.py: dump bitmaps header extension Add class for bitmap extension and dump its fields. Further work is to dump bitmap directory. Test new functionality inside 291 iotest. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Andrey Shinkevich Message-Id: <20200606081806.23897-14-vsementsov@virtuozzo.com> [eblake: fix iotest output] Signed-off-by: Eric Blake --- tests/qemu-iotests/291 | 4 ++++ tests/qemu-iotests/291.out | 33 ++++++++++++++++++++++++++++++ tests/qemu-iotests/qcow2_format.py | 42 ++++++++++++++++++++++++++++++-------- 3 files changed, 70 insertions(+), 9 deletions(-) diff --git a/tests/qemu-iotests/291 b/tests/qemu-iotests/291 index 3ca83b9cd1..e0cffc7cb1 100755 --- a/tests/qemu-iotests/291 +++ b/tests/qemu-iotests/291 @@ -62,6 +62,8 @@ $QEMU_IO -c 'w 1M 1M' -f $IMGFMT "$TEST_IMG" | _filter_qemu_io $QEMU_IMG bitmap --disable -f $IMGFMT "$TEST_IMG" b1 $QEMU_IMG bitmap --enable -f $IMGFMT "$TEST_IMG" b2 $QEMU_IO -c 'w 2M 1M' -f $IMGFMT "$TEST_IMG" | _filter_qemu_io +echo "Check resulting qcow2 header extensions:" +$PYTHON qcow2.py "$TEST_IMG" dump-header-exts echo echo "=== Bitmap preservation not possible to non-qcow2 ===" @@ -88,6 +90,8 @@ $QEMU_IMG bitmap --merge tmp -f $IMGFMT "$TEST_IMG" b0 $QEMU_IMG bitmap --remove --image-opts \ driver=$IMGFMT,file.driver=file,file.filename="$TEST_IMG" tmp $QEMU_IMG info "$TEST_IMG" | _filter_img_info --format-specific +echo "Check resulting qcow2 header extensions:" +$PYTHON qcow2.py "$TEST_IMG" dump-header-exts echo echo "=== Check bitmap contents ===" diff --git a/tests/qemu-iotests/291.out b/tests/qemu-iotests/291.out index 8c62017567..ccfcdc5e35 100644 --- a/tests/qemu-iotests/291.out +++ b/tests/qemu-iotests/291.out @@ -14,6 +14,25 @@ wrote 1048576/1048576 bytes at offset 1048576 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) wrote 1048576/1048576 bytes at offset 2097152 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Check resulting qcow2 header extensions: +Header extension: +magic 0xe2792aca (Backing format) +length 5 +data 'qcow2' + +Header extension: +magic 0x6803f857 (Feature table) +length 336 +data + +Header extension: +magic 0x23852875 (Bitmaps) +length 24 +nb_bitmaps 2 +reserved32 0 +bitmap_directory_size 0x40 +bitmap_directory_offset 0x510000 + === Bitmap preservation not possible to non-qcow2 === @@ -65,6 +84,20 @@ Format specific information: granularity: 65536 refcount bits: 16 corrupt: false +Check resulting qcow2 header extensions: +Header extension: +magic 0x6803f857 (Feature table) +length 336 +data + +Header extension: +magic 0x23852875 (Bitmaps) +length 24 +nb_bitmaps 3 +reserved32 0 +bitmap_directory_size 0x60 +bitmap_directory_offset 0x520000 + === Check bitmap contents === diff --git a/tests/qemu-iotests/qcow2_format.py b/tests/qemu-iotests/qcow2_format.py index 40b5bf467b..0f65fd161d 100644 --- a/tests/qemu-iotests/qcow2_format.py +++ b/tests/qemu-iotests/qcow2_format.py @@ -103,6 +103,19 @@ class Qcow2Struct(metaclass=Qcow2StructMeta): print('{:<25} {}'.format(f[2], value_str)) +class Qcow2BitmapExt(Qcow2Struct): + + fields = ( + ('u32', '{}', 'nb_bitmaps'), + ('u32', '{}', 'reserved32'), + ('u64', '{:#x}', 'bitmap_directory_size'), + ('u64', '{:#x}', 'bitmap_directory_offset') + ) + + +QCOW2_EXT_MAGIC_BITMAPS = 0x23852875 + + class QcowHeaderExtension(Qcow2Struct): class Magic(Enum): @@ -110,7 +123,7 @@ class QcowHeaderExtension(Qcow2Struct): 0xe2792aca: 'Backing format', 0x6803f857: 'Feature table', 0x0537be77: 'Crypto header', - 0x23852875: 'Bitmaps', + QCOW2_EXT_MAGIC_BITMAPS: 'Bitmaps', 0x44415441: 'Data file' } @@ -130,8 +143,11 @@ class QcowHeaderExtension(Qcow2Struct): This should be somehow refactored and functionality should be moved to superclass (to allow creation of any qcow2 struct), but then, fields of variable length (data here) should be supported in base class - somehow. So, it's a TODO. We'll see how to properly refactor this when - we have more qcow2 structures. + somehow. Note also, that we probably want to parse different + extensions. Should they be subclasses of this class, or how to do it + better? Should it be something like QAPI union with discriminator field + (magic here). So, it's a TODO. We'll see how to properly refactor this + when we have more qcow2 structures. """ if fd is None: assert all(v is not None for v in (magic, length, data)) @@ -148,15 +164,23 @@ class QcowHeaderExtension(Qcow2Struct): self.data = fd.read(padded) assert self.data is not None - def dump(self): - data = self.data[:self.length] - if all(c in string.printable.encode('ascii') for c in data): - data = f"'{ data.decode('ascii') }'" + if self.magic == QCOW2_EXT_MAGIC_BITMAPS: + self.obj = Qcow2BitmapExt(data=self.data) else: - data = '' + self.obj = None + def dump(self): super().dump() - print(f'{"data":<25} {data}') + + if self.obj is None: + data = self.data[:self.length] + if all(c in string.printable.encode('ascii') for c in data): + data = f"'{ data.decode('ascii') }'" + else: + data = '' + print(f'{"data":<25} {data}') + else: + self.obj.dump() @classmethod def create(cls, magic, data): -- 2.11.0