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authorKevin Wolf <kwolf@redhat.com>2011-11-16 11:35:54 +0100
committerKevin Wolf <kwolf@redhat.com>2011-12-15 12:40:33 +0100
commitc2c9a46609164a36b477f6cff1d10ed27a6b53fc (patch)
tree7cf3cf48bcc3e87a93457b5bb5ef9a7cc468ca2e /docs/specs
parent3763f26f2fdff156fec6868b651fe7853fc64de5 (diff)
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qcow2: Allow >4 GB VM state
This is a compatible extension to the snapshot header format that allows saving a 64 bit VM state size. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'docs/specs')
-rw-r--r--docs/specs/qcow2.txt8
1 files changed, 7 insertions, 1 deletions
diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt
index e792953..b6adcad 100644
--- a/docs/specs/qcow2.txt
+++ b/docs/specs/qcow2.txt
@@ -253,7 +253,13 @@ Snapshot table entry:
36 - 39: Size of extra data in the table entry (used for future
extensions of the format)
- variable: Extra data for future extensions. Must be ignored.
+ variable: Extra data for future extensions. Unknown fields must be
+ ignored. Currently defined are (offset relative to snapshot
+ table entry):
+
+ Byte 40 - 47: Size of the VM state in bytes. 0 if no VM
+ state is saved. If this field is present,
+ the 32-bit value in bytes 32-35 is ignored.
variable: Unique ID string for the snapshot (not null terminated)