And because of that, it's entirely disabled for now. Both versions
are similar enough that a single header definition works for both
of them. The only "diverting" side-effect is that the union of the
two is larger than the official V1 header.
What this means for our V1 support is that we can't put the L1 table
adjacent to the V1 header (i.e. at offset 0x30 in the file), unless
we revert to hackery and klugery. Let's not. Instead, we align the L1
table at the cluster boundary. This is in line with the V2 layout and
perfectly ok for V1 anyway (ok -- as far as I've seen so far).
Due to the alignment, our V1 image seems to be 1 cluster larger than
the V1 image created by qemu-img (on average).
Compression of the clusters is not supported at this time.
MFC after: 2 months
-T (track size) or -H (number of heads) is given:
o scheme_metadata() always rounded to the block size. This is not
always valid (e.g. vtoc8 that must have partitions start at cylinder
boundaries).
o The bsd and vtoc8 schemes "resized" the image to make it match the
geometry, but since the geometry is an approximation and the size
of the image computed from cylinders * heads * sectors is always
smaller than the original image size, the partition information ran
out of bounds.
The fix is to have scheme_metadata() simply pass it's arguments to the
per-scheme metadata callback, so that schemes not only know where the
metadata is to go, but also what the current block address is. It's now
up to the per-scheme callback to reserve room for metadata and to make
sure alignment and rounding is applied.
The BSD scheme now has the most elaborate alignment and rounding. Just
to make the point: partitions are aligned on block boundaries, but the
image is rounded to the next cyclinder boundary.
vtoc8 now properly has all partitions aligned (and rounded) to the
cyclinder boundary.
Obtained from: Juniper Networks, Inc.
MFC after: 3 days
numbers or names. This gives more control over the actual layout and
helps to construct BSD disklabels with /usr or /var at dedicated
partitions.
Obtained from: Juniper Networks, Inc.
MFC after: 3 days
Relnotes: yes
the second sector by only clearing the amount of bytes needed for the
disklabel in the second sector. Previously we were clearing exactly 1
sector worth of bytes and as such writing over boot code that may have
been there.
Since we do support more than 8 partitions, make sure to set all fields
in d_partitions. For the first 8 partitions this is unneeded, but for
partitioons 9 and up this compensates for the fact that we don't clear
an entire sector anymore.
Obviously, one cannot use more than 8 partitions when using boot code
that starts right after the disk label.
Relevant GRNs:
107879 - Employ unused bytes after the disklabel in the second sector.
189500 - Revert the part of change 107879 that employs the unused bytes
after the disklabel in the 2nd sector for boot code.
Obtained from: Juniper Networks, Inc.
MFC after: 3 days
1. Iterate over all partitions counted in the label, which can be more
than the number of partitions given to mkimg(1).
2. Start the checksum from the beginning of the label; not the beginning
of the bootarea.
Tested with bsdlabel(8).
MFC after: 3 days
cheating by assigning the same sector offset to both directories,
but it seems that VirtualBox doesn't like that. Neither does
qemu from the looks of it. We now actually write the directory
and table twice.
MFC after: 3 days
a raw image with a VHD footer appended. There's little value that I
can see to use the fixed image type, but in order to make VHD images
for use by Microsoft's Azure platform, they must be fixed VHD images.
Support has been added by refactoring the code to re-use common code
and by adding a second output format structure. To created fixed VHD
images, specify "vhdf" as the output format.
Use this for VHD and VMDK to avoid allocating space in the image
for empty sectors.
Note that this negatively affects performance because mkimg uses a
temporary file for the intermediate storage. When mkimg has better
internal book keeping, performance can be significantly improved.
among others.
Add an undocumented option for unit testing (-y). When given, the image
will have UUIDs and timestamps synthesized in a way that gives identical
results across runs. As such, UUIDs stop being unique, globally or
otherwise.
VHD support requested by: gjb@
Add support for different output formats:
1. The output file that was previously written is now called the raw format.
2. Add the vmdk output format to create VMDK images.
When the format is not given, the raw output format is assumed.
sector granularity for both offset and length. Have all schemes
use mkimg_write() instead of mkimg_seek() followed by write(2).
Now that schemes don't use lseek(2) nor write(2) directly, it's
easier to support output formats other than raw disks.
