Commit a50c1f57 authored by Alberto Garcia's avatar Alberto Garcia Committed by Kevin Wolf
Browse files

qcow2: Add incompatibility note between backing files and raw external data files 



Backing files and raw external data files are mutually exclusive.
The documentation of the raw external data bit (in autoclear_features)
already indicates that, but we should also mention it on the other
side.

Suggested-by: default avatarEric Blake <eblake@redhat.com>
Signed-off-by: default avatarAlberto Garcia <berto@igalia.com>
Message-Id: <20200410121816.8334-1-berto@igalia.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 16aaacb3

docs/interop/qcow2.txt

+3 −0
Original line number Diff line number Diff line
@@ -25,6 +25,9 @@ The first cluster of a qcow2 image contains the file header: 
                    is stored (NB: The string is not null terminated). 0 if the

                    image doesn't have a backing file.



                    Note: backing files are incompatible with raw external data

                    files (auto-clear feature bit 1).



         16 - 19:   backing_file_size

                    Length of the backing file name in bytes. Must not be

                    longer than 1023 bytes. Undefined if the image doesn't have