Use the "at" variants of the read/write functions in the block device.
This reduces the number of syscalls on the host per I/O to one
(pread64/pwrite64) rather than two (lseek + read/write).
The CompositeDiskFile implementation is also updated in this commit,
since it's both a producer and consumer of DiskFile, and it isn't
trivial to update it in a separate commit without breaking compilation.
BUG=None
TEST=Start Crostini on kevin, banon, and nami
Change-Id: I031e7e87cd6c99504db8c56b1725ea51c1e27a53
Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1845948
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Stephen Barber <smbarber@chromium.org>
This adds a new disk file type next to raw files and qcow images that
represent an indirection to further raw disk files. The disk file
itself is a proto file with references to file paths for other disks to
open and their virtual offsets and lengths.
The intention is to make it easy to assemble a single virtual hard disk
out of several distinct partition files. In the particular case of
Cuttlefish running Android in a VM, this is relevant as the Android
build system distributes partitions as separate raw files. While the
simple solution is to pass each partition as a separate raw disk, some
functionality (like the bootloader) assumes there is a partition table
with multiple distinct partitions on a single disk.
Implementing composite disk support in the VMM bridges this gap through
supporting the general-purpose case of a disk built out of multiple
component files.
If desired, this can be extended to support qcow files to support
unusual configurations like a mixed qcow/raw disk.
Enabled with the "composite-disk" feature.
Bug: b/133432409
Change-Id: I2b0c47d92fab13b5dc0ca5a960c7cfd2b7145b87
Signed-off-by: Cody Schuffelen <schuffelen@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1667767
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Commit-Queue: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
This supports virtio disks that depend on multiple file descriptors. All
of the file descriptors are passed to the jail when relevant.
Bug: b/133432409
Change-Id: Idf2e24cd2984c0d12a47a523c13d24c1ba8d173e
Signed-off-by: Cody Schuffelen <schuffelen@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1691761
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
