vhost-user-backend: Allow AtomicBitmap#353
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This is needed for Cloud Hypervisor. Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
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The vhost_user_block device uses the vhost_user_backend crate to implement the vhost-user protocol. For live migration reasons, this crate only supports the BitmapMmapRegion bitmap, which is slower than the AtomicBitmap used by the rest of Cloud Hypervisor. The block crate is going to be using this bitmap in many more places, so supporting both would require making the whole crate generic. This is undesirable. A better approach is to use a Cargo feature to select the bitmap. However, all crates within a workspace must use the same Cargo features. Therefore, the vhost_user_block server needs to be moved out of the workspace. Disable it for now. It will be reenabled once rust-vmm/vhost#353 is merged and a new release of the vhost crate is made. Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
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Hi, Is this PR related to #352 ? |
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Summary of the PR
cloud-hypervisor/cloud-hypervisor#7971 changes the block layer to require that AtomicBitmap is used. This breaks the vhost-user server. Since this server is only for testing, making the whole block layer generic is undesirable.
Allow AtomicBitmap to be used when migration is not needed.
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test.
Release" section of CHANGELOG.md (if no such section exists, please create one).
unsafecode is properly documented.