xen: fix wrong SPDX headers of Xen related headers

Commit b24413180f5600 ("License cleanup: add SPDX GPL-2.0 license
identifier to files with no license") was meant to do a tree-wide
cleanup for files without any license information by adding a SPDX
GPL-2.0 line to them.

Unfortunately this was applied even to several Xen-related headers
which have been originally under the MIT license, but obviously have
been copied to the Linux tree from the Xen project without keeping the
license boiler plate as required.

Correct that by changing the license of those files back to "MIT".

Some files still contain the MIT license text. Replace that by the
related SPDX line.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20211015143312.29900-1-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

x86/xen/time: setup vcpu 0 time info page

In order to support pvclock vdso on xen we need to setup the time
info page for vcpu 0 and register the page with Xen using the
VCPUOP_register_vcpu_time_memory_area hypercall. This hypercall
will also forcefully update the pvti which will set some of the
necessary flags for vdso. Afterwards we check if it supports the
PVCLOCK_TSC_STABLE_BIT flag which is mandatory for having
vdso/vsyscall support. And if so, it will set the cpu 0 pvti that
will be later on used when mapping the vdso image.

The xen headers are also updated to include the new hypercall for
registering the secondary vcpu_time_info struct.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

xen: update xen headers

Update some Xen headers to be able to use new functionality.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

xen: Support 64-bit PV guest receiving NMIs

This is based on a patch that Zhenzhong Duan had sent - which
was missing some of the remaining pieces. The kernel has the
logic to handle Xen-type-exceptions using the paravirt interface
in the assembler code (see PARAVIRT_ADJUST_EXCEPTION_FRAME -
pv_irq_ops.adjust_exception_frame and and INTERRUPT_RETURN -
pv_cpu_ops.iret).

That means the nmi handler (and other exception handlers) use
the hypervisor iret.

The other changes that would be neccessary for this would
be to translate the NMI_VECTOR to one of the entries on the
ipi_vector and make xen_send_IPI_mask_allbutself use different
events.

Fortunately for us commit 1db01b4903639fcfaec213701a494fe3fb2c490b
(xen: Clean up apic ipi interface) implemented this and we piggyback
on the cleanup such that the apic IPI interface will pass the right
vector value for NMI.

With this patch we can trigger NMIs within a PV guest (only tested
x86_64).

For this to work with normal PV guests (not initial domain)
we need the domain to be able to use the APIC ops - they are
already implemented to use the Xen event channels. For that
to be turned on in a PV domU we need to remove the masking
of X86_FEATURE_APIC.

Incidentally that means kgdb will also now work within
a PV guest without using the 'nokgdbroundup' workaround.

Note that the 32-bit version is different and this patch
does not enable that.

CC: Lisa Nguyen <lisa@xenapiadmin.com>
CC: Ben Guthro <benjamin.guthro@citrix.com>
CC: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v1: Fixed up per David Vrabel comments]
Reviewed-by: Ben Guthro <benjamin.guthro@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>

xen: add missing definitions in include/xen/interface/vcpu.h which ia64/xen needs

Add xen handles realted definitions for xen vcpu which ia64/xen needs.
Pointer argumsnts for ia64/xen hypercall are passed in pseudo physical
address (guest physical address) so that it is required to convert
guest kernel virtual address into pseudo physical address.
The xen guest handle represents such arguments.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

xen: fix incorrect vcpu_register_vcpu_info hypercall argument

The kernel's copy of struct vcpu_register_vcpu_info was out of date,
at best causing the hypercall to fail and the guest kernel to fall
back to the old mechanism, or worse, causing random memory corruption.

[ Stable folks: applies to 2.6.23 ]

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Morten =?utf-8?q?B=C3=B8geskov?= <xen-users@morten.bogeskov.dk>
Cc: Mark Williamson <mark.williamson@cl.cam.ac.uk>

xen: Place vcpu_info structure into per-cpu memory

An experimental patch for Xen allows guests to place their vcpu_info
structs anywhere. We try to use this to place the vcpu_info into the
PDA, which allows direct access.

If this works, then switch to using direct access operations for
irq_enable, disable, save_fl and restore_fl.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Keir Fraser <keir@xensource.com>

xen: Add Xen interface header files

Add Xen interface header files. These are taken fairly directly from
the Xen tree, but somewhat rearranged to suit the kernel's conventions.

Define macros and inline functions for doing hypercalls into the
hypervisor.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>