On 13.08.2025 00:30, 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> > Reviewed-by: Alejandro Vallejo <alejandro.garciavall...@amd.com> > --- > Changes since v15: > - fixup for check after the first pass in the bitarray in domid_alloc() > - trivial renaming for the local variable in domid_alloc() > - kept Julien's R-b, added Alejandro's R-b
Just to mention: My take is that this kind of a fix ought to invalidate all earlier R-b. It's not just a cosmetic change, after all. Jan
