Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

>>> On 15.01.16 at 15:55, wrote: > On Fri, 2016-01-15 at 07:39 -0700, Jan Beulich wrote: >> I don't think I agree - there are two models. The meaning of >> -E2BIG for the caller to retry with a smaller amount doesn't exist in >> the new model anymore, and hence libxc

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

On Mon, 2016-01-18 at 01:11 -0700, Jan Beulich wrote: > > > > On 15.01.16 at 15:55, wrote: > > On Fri, 2016-01-15 at 07:39 -0700, Jan Beulich wrote: > > > I don't think I agree - there are two models. The meaning of > > > -E2BIG for the caller to retry with a smaller

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

On Mon, 2016-01-18 at 09:51 -0700, Jan Beulich wrote: > > > > On 18.01.16 at 17:32, wrote: > > I must confess I'm not entirely following what the various proposals > > are, > > What is currently implemented by the patch is that, upon error on > iteration N the hypervisor

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

>>> On 18.01.16 at 17:32, wrote: > I must confess I'm not entirely following what the various proposals are, What is currently implemented by the patch is that, upon error on iteration N the hypervisor would clean up on a best effort basis and return the error indicator.

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

On Thu, 2016-01-14 at 03:04 -0700, Jan Beulich wrote: > - ARM side unimplemented (and hence libxc for now made cope with both >   models), So, one model is the one described in the commit message: > - zero (success, everything done) > - positive (success, this many done, more to do: re-invoke) > 

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

>>> On 15.01.16 at 11:09, wrote: > On Thu, 2016-01-14 at 03:04 -0700, Jan Beulich wrote: >> - ARM side unimplemented (and hence libxc for now made cope with both >> models), > > So, one model is the one described in the commit message: > >> - zero (success, everything

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

On Fri, 2016-01-15 at 03:47 -0700, Jan Beulich wrote: > > > > On 15.01.16 at 11:09, wrote: > > On Thu, 2016-01-14 at 03:04 -0700, Jan Beulich wrote: > > > - ARM side unimplemented (and hence libxc for now made cope with both > > >   models), > > > > So, one model is the

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

>>> On 15.01.16 at 14:57, wrote: > On Fri, 2016-01-15 at 03:47 -0700, Jan Beulich wrote: >> > > > On 15.01.16 at 11:09, wrote: >> > On Thu, 2016-01-14 at 03:04 -0700, Jan Beulich wrote: >> > > - ARM side unimplemented (and hence libxc for now

Re: [Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

On Fri, 2016-01-15 at 07:39 -0700, Jan Beulich wrote: > > > > On 15.01.16 at 14:57, wrote: > > On Fri, 2016-01-15 at 03:47 -0700, Jan Beulich wrote: > > > > > > On 15.01.16 at 11:09, wrote: > > > > On Thu, 2016-01-14 at 03:04 -0700, Jan Beulich

[Xen-devel] [PATCH v3] x86/p2m: use large pages for MMIO mappings

When mapping large BARs (e.g. the frame buffer of a graphics card) the overhead of establishing such mappings using only 4k pages has, particularly after the XSA-125 fix, become unacceptable. Alter the XEN_DOMCTL_memory_mapping semantics once again, so that there's no longer a fixed amount of