30.07.2020 17:15, Andrey Shinkevich wrote:
Add bitmap table information to the QCOW2 metadata dump.
Bitmap name bitmap-1
...
Bitmap table type size offset
0 serialized 65536 10092544
1 all-zeroes 65536 0
For serialized, size and offset are size and offset of bitmap table.
But, all-zeroes bitmaps don't have any bitmap table, so size and offset
both are undefined (OK to print zero for them, but 65536 is unrelated).
2 all-zeroes 65536 0
Signed-off-by: Andrey Shinkevich <[email protected]>
---
tests/qemu-iotests/303.out | 4 ++++
tests/qemu-iotests/qcow2_format.py | 47 ++++++++++++++++++++++++++++++++++++++
2 files changed, 51 insertions(+)
diff --git a/tests/qemu-iotests/303.out b/tests/qemu-iotests/303.out
index dc3739b..d581fb4 100644
--- a/tests/qemu-iotests/303.out
+++ b/tests/qemu-iotests/303.out
@@ -70,6 +70,8 @@ type 1
granularity_bits 15
name_size 8
extra_data_size 0
+Bitmap table type size offset
+0 serialized 65536 10092544
Bitmap name bitmap-2
bitmap_table_offset 0x9c0000
@@ -79,4 +81,6 @@ type 1
granularity_bits 16
name_size 8
extra_data_size 0
+Bitmap table type size offset
+0 all-zeroes 65536 0
diff --git a/tests/qemu-iotests/qcow2_format.py b/tests/qemu-iotests/qcow2_format.py
index ca0d350..1f033d4 100644
--- a/tests/qemu-iotests/qcow2_format.py
+++ b/tests/qemu-iotests/qcow2_format.py
@@ -175,6 +175,10 @@ class Qcow2BitmapDirEntry(Qcow2Struct):
entry_raw_size = self.bitmap_dir_entry_raw_size()
padding = ((entry_raw_size + 7) & ~7) - entry_raw_size
fd.seek(padding, 1)
+ self.bitmap_table = Qcow2BitmapTable(fd=fd,
+ offset=self.bitmap_table_offset,
+ nb_entries=self.bitmap_table_size,
+ cluster_size=self.cluster_size)
def bitmap_dir_entry_raw_size(self):
return struct.calcsize(self.fmt) + self.name_size + \
@@ -183,6 +187,49 @@ class Qcow2BitmapDirEntry(Qcow2Struct):
def dump(self):
print(f'{"Bitmap name":<25} {self.name}')
super(Qcow2BitmapDirEntry, self).dump()
+ self.bitmap_table.dump()
+
+
+class Qcow2BitmapTableEntry(Qcow2Struct):
+
+ fields = (
+ ('u64', '{}', 'entry'),
+ )
+
+ BME_TABLE_ENTRY_RESERVED_MASK = 0xff000000000001fe
+ BME_TABLE_ENTRY_OFFSET_MASK = 0x00fffffffffffe00
+ BME_TABLE_ENTRY_FLAG_ALL_ONES = 1
+
+ def __init__(self, fd):
+ super().__init__(fd=fd)
+ self.reserved = self.entry & self.BME_TABLE_ENTRY_RESERVED_MASK
+ self.offset = self.entry & self.BME_TABLE_ENTRY_OFFSET_MASK
+ if self.offset:
+ if self.entry & self.BME_TABLE_ENTRY_FLAG_ALL_ONES:
+ self.type = 'invalid'
+ else:
+ self.type = 'serialized'
+ elif self.entry & self.BME_TABLE_ENTRY_FLAG_ALL_ONES:
+ self.type = 'all-ones'
+ else:
+ self.type = 'all-zeroes'
+
+
+class Qcow2BitmapTable:
+
+ def __init__(self, fd, offset, nb_entries, cluster_size):
+ self.cluster_size = cluster_size
+ position = fd.tell()
+ fd.seek(offset)
+ self.entries = [Qcow2BitmapTableEntry(fd) for _ in range(nb_entries)]
+ fd.seek(position)
+
+ def dump(self):
+ size = self.cluster_size
+ bitmap_table = enumerate(self.entries)
+ print(f'{"Bitmap table":<14} {"type":<15} {"size":<12} {"offset"}')
+ for i, entry in bitmap_table:
+ print(f'{i:<14} {entry.type:<15} {size:<12} {entry.offset}')
All this looks like 'cluster_size' is not really needed for Qcow2BitmapTable
class (we can print only offsets).
Still, if you want to save it, can we print it only for entries with
'serialized' type?
It's minor, I'm OK with it as is:
Reviewed-by: Vladimir Sementsov-Ogievskiy <[email protected]>
QCOW2_EXT_MAGIC_BITMAPS = 0x23852875
--
Best regards,
Vladimir
