On Mon, Oct 05, 2020 at 02:35:03PM +0200, Claudio Imbrenda wrote: > On Mon, 5 Oct 2020 13:54:42 +0200 > Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote: > > [...] > > > While doing a page allocator, the topology is not the only > > characteristic we may need to specify. > > Specific page characteristics like rights, access flags, cache > > behavior may be useful when testing I/O for some architectures. > > This obviously will need some connection to the MMU handling. > > > > Wouldn't it be interesting to use a bitmap flag as argument to > > page_alloc() to define separate regions, even if the connection with > > the MMU is done in a future series? > > the physical allocator is only concerned with the physical pages. if > you need special MMU flags to be set, then you should enable the MMU > and fiddle with the flags and settings yourself. > Given enough need, we could create a collection of functions like alloc_pages_ro() alloc_pages_uncached() ... These functions wouldn't have generic implementations, only arch-specific implementations, and those implementations would simply do a typical allocation, followed by an iteration of each PTE where the arch-specific flags get set. Thanks, drew
