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authorAlberto Garcia2020-04-10 14:18:15 +0200
committerKevin Wolf2020-04-30 17:51:06 +0200
commita50c1f57e491ba17c0fcb7d285dfe04770be0a70 (patch)
tree4b523b49b48f8140122e6c7eb30d974956013e36 /docs/interop
parentMerge remote-tracking branch 'remotes/cohuck/tags/s390x-20200430' into staging (diff)
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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: Eric Blake <eblake@redhat.com> Signed-off-by: Alberto Garcia <berto@igalia.com> Message-Id: <20200410121816.8334-1-berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'docs/interop')
-rw-r--r--docs/interop/qcow2.txt3
1 files changed, 3 insertions, 0 deletions
diff --git a/docs/interop/qcow2.txt b/docs/interop/qcow2.txt
index 640e0eca40..298a031310 100644
--- a/docs/interop/qcow2.txt
+++ b/docs/interop/qcow2.txt
@@ -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