On Tue, May 04, 2021 at 03:11:54PM -0700, Jacob Pan wrote: > > It is a weird way to use xarray to have a structure which > > itself is just a wrapper around another RCU protected structure. > > > > Make the caller supply the ioasid_data memory, embedded in its own > > element, get rid of the void * and rely on XA_ZERO_ENTRY to hold > > allocated but not active entries. > > > Let me try to paraphrase to make sure I understand. Currently > struct ioasid_data is private to the iasid core, its memory is allocated by > the ioasid core. > > You are suggesting the following: > 1. make struct ioasid_data public > 2. caller allocates memory for ioasid_data, initialize it then pass it to > ioasid_alloc to store in the xarray > 3. caller will be responsible for setting private data inside ioasid_data > and do call_rcu after update if needed. Basically, but you probably won't need a "private data" once the caller has this struct as it can just embed it in whatever larger struct makes sense for it and use container_of/etc I didn't look too closely at the whole thing though. Honestly I'm a bit puzzled why we need a pluggable global allocator framework.. The whole framework went to some trouble to isolate everything into iommu drivers then that whole design is disturbed by this global thing. Jason
