Hi Denis, On 08/08/2025 03:19, dm...@proton.me wrote:
From: Denis Mukhin <dmuk...@ford.com>Currently, there are two different domain ID allocation implementations: 1) Sequential IDs allocation in dom0less Arm code based on max_init_domid; 2) Sequential IDs allocation in XEN_DOMCTL_createdomain; does not use max_init_domid (both Arm and x86). The domain ID allocation covers dom0 or late hwdom, predefined domains, post-boot domains, excluding Xen system domains (domid >= DOMID_FIRST_RESERVED). It makes sense to have a common helper code for such task across architectures (Arm and x86) and between dom0less / toolstack domU allocation. Note, fixing dependency on max_init_domid is out of scope of this patch. Wrap the domain ID allocation as an arch-independent function domid_alloc() in new common/domid.c based on the bitmap. Allocation algorithm: - If an explicit domain ID is provided, verify its availability and use it if ID is not used; - If DOMID_INVALID is provided, search the range [1..DOMID_FIRST_RESERVED-1], starting from the last used ID. Implementation guarantees that two consecutive calls will never return the same ID. ID#0 is reserved for the first boot domain (currently, dom0) and excluded from the allocation range. Remove is_free_domid() helper as it is not needed now. No functional change intended. Signed-off-by: Denis Mukhin <dmuk...@ford.com>
Reviewed-by: Julien Grall <jgr...@amazon.com> Cheers, -- Julien Grall
