Lines Matching +full:- +full:- +full:-
7 +----------+----------+----------+-----+
9 +----------+----------+----------+-----+
22 All fields are little-endian.
25 ------
38 uint64_t autoclear_features; /* self-resetting feature bits */
51 - ``cluster_size`` must be a power of 2 in range [2^12, 2^26].
52 - ``table_size`` must be a power of 2 in range [1, 16].
53 - ``header_size`` is the number of clusters used by the header and any additional
55 - ``features``, ``compat_features``, and ``autoclear_features`` are file format
58 - An image with unknown ``features`` bits enabled must not be opened. File format
59 changes that are not backwards-compatible must use ``features`` bits.
60 - An image with unknown ``compat_features`` bits enabled can be opened safely.
61 The unknown features are simply ignored and represent backwards-compatible
63 - An image with unknown ``autoclear_features`` bits enable can be opened safely
64 after clearing the unknown bits. This allows for backwards-compatible changes
65 to the file format which degrade gracefully and can be re-enabled again by a
67 - ``l1_table_offset`` is the offset of the first byte of the L1 table in the image
69 - ``image_size`` is the block device size seen by the guest and must be a multiple
71 - ``backing_filename_offset`` and ``backing_filename_size`` describe a string in
72 (byte offset, byte size) form. It is not NUL-terminated and has no alignment constraints.
79 - ``QED_F_BACKING_FILE = 0x01``. The image uses a backing file.
80 - ``QED_F_NEED_CHECK = 0x02``. The image needs a consistency check before use.
81 - ``QED_F_BACKING_FORMAT_NO_PROBE = 0x04``. The backing file is a raw disk image
93 ------
108 +----------+
110 +----------+
111 ,------' | '------.
112 +----------+ | +----------+
114 +----------+ +----------+
115 ,------' | '------.
116 +----------+ | +----------+
118 +----------+ +----------+
137 - 0 - unallocated. The L2 table is not yet allocated.
142 - 0 - unallocated. The data cluster is not yet allocated.
143 - 1 - zero. The data cluster contents are all zeroes and no cluster is allocated.
145 Future format extensions may wish to store per-offset information. The least
165 Zero data clusters are a space-efficient way of storing zeroed regions of the image.
182 <--------> <--------> <--------------->
183 +----------+----------+-----------------+
185 +----------+----------+-----------------+
189 offset_mask = ~(cluster_size - 1) # mask for the image file byte offset
198 --------------------
210 - Each cluster is referenced once and only once. It is an inconsistency to have
213 - Offsets must be within the image file size and must be ``cluster_size`` aligned.
214 - Table offsets must at least ``table_size`` * ``cluster_size`` bytes from the end