It may happen that Xen's and Linux's ideas of vCPU id diverge. In
particular, when we crash on a secondary vCPU we may want to do kdump
and unlike plain kexec where we do migrate_to_reboot_cpu() we try
booting on the vCPU which crashed. This doesn't work very well for
PVHVM guests as we have a number of hypercalls where we pass vCPU id
as a parameter. These hypercalls either fail or do something
unexpected.

To solve the issue introduce percpu xen_vcpu_id mapping. ARM and PV
guests get direct mapping for now. Boot CPU for PVHVM guest gets its
id from CPUID. With secondary CPUs it is a bit more
trickier. Currently, we initialize IPI vectors before these CPUs boot
so we can't use CPUID. Use ACPI ids from MADT instead.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Currently we don't save ACPI ids (unlike LAPIC ids which go to
x86_cpu_to_apicid) from MADT and we may need this information later.
Particularly, ACPI ids is the only existent way for a PVHVM Xen guest
to figure out Xen's idea of its vCPUs ids before these CPUs boot and
in some cases these ids diverge from Linux's cpu ids.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Update cpuid.h header from xen hypervisor tree to get
XEN_HVM_CPUID_VCPU_ID_PRESENT definition.
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

IOCTL_EVTCHN_RESTRICT limits the file descriptor to being able to bind
to interdomain event channels from a specific domain.  Event channels
that are already bound continue to work for sending and receiving
notifications.

This is useful as part of deprivileging a user space PV backend or
device model (QEMU).  e.g., Once the device model as bound to the
ioreq server event channels it can restrict the file handle so an
exploited DM cannot use it to create or bind to arbitrary event
channels.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

Commit 9d092603 ("xen-blkback: do not leak mode property") left one
path unfixed; correct this.
Acked-by: NJens Axboe <axboe@kernel.dk>
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The functions these get passed to have been taking pointers to const
since at least 2.6.16.
Acked-by: NJens Axboe <axboe@kernel.dk>
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

... for single items being collected: It is more typesafe (as the
compiler can check format string and to-be-written-to variable match)
and requires one less parameter to be passed.
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Acked-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

... for single items being collected: It is more typesafe (as the
compiler can check format string and to-be-written-to variable match)
and requires one less parameter to be passed.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Acked-by: NJens Axboe <axboe@kernel.dk>

Up to now reading the stolen time of a remote cpu was not possible in a
performant way under Xen. This made support of runqueue steal time via
paravirt_steal_rq_enabled impossible.

With the addition of an appropriate hypervisor interface this is now
possible, so add the support.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Add support for the Xen HYPERVISOR_vm_assist hypercall.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Reviewed-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Update some Xen headers to be able to use new functionality.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

req_start is simply an alias of the "offset" function parameter, and
req_end is being used just once in each function. (And both variables
were loop invariant anyway, so should at least have got initialized
outside the loop.)
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

There's no point calling xen_pcibk_config_read() here - all it'll do is
return whatever conf_space_read() returns for the field which was found
here (and which would be found there again). Also there's no point
clearing tmp_val before the call.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Other than for raw BAR values, flags are properly separated in the
internal representation.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

It is now identical to bar_init().
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The kernel.h macro DIV_ROUND_UP performs the computation
(((n) + (d) - 1) /(d)) but is perhaps more readable.

The Coccinelle script used to make this change is as follows:
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)
Signed-off-by: NAmitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

System workqueues have been able to handle high level of concurrency
for a long time now and there's no reason to use dedicated workqueues
just to gain concurrency.  Replace dedicated xenbus_frontend_wq with the
use of system_wq.

Unlike a dedicated per-cpu workqueue created with create_workqueue(),
system_wq allows multiple work items to overlap executions even on
the same CPU; however, a per-cpu workqueue doesn't have any CPU
locality or global ordering guarantees unless the target CPU is
explicitly specified and the increase of local concurrency shouldn't
make any difference.

In this case, there is only a single work item, increase of concurrency
level by switching to system_wq should not make any difference.
Signed-off-by: NBhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

System workqueues have been able to handle high level of concurrency
for a long time now and there's no reason to use dedicated workqueues
just to gain concurrency.  Replace dedicated xen_pcibk_wq with the
use of system_wq.

Unlike a dedicated per-cpu workqueue created with create_workqueue(),
system_wq allows multiple work items to overlap executions even on
the same CPU; however, a per-cpu workqueue doesn't have any CPU
locality or global ordering guarantees unless the target CPU is
explicitly specified and thus the increase of local concurrency shouldn't
make any difference.

Since the work items could be pending, flush_work() has been used in
xen_pcibk_disconnect(). xen_pcibk_xenbus_remove() calls free_pdev()
which in turn calls xen_pcibk_disconnect() for every pdev to ensure that
there is no pending task while disconnecting the driver.
Signed-off-by: NBhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

This will match how PMU errors are reported at check_hw_exists()'s
msr_fail label, which is reached when VPMU initialzation fails.
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The pv_time_ops structure contains a function pointer for the
"steal_clock" functionality used only by KVM and Xen on ARM. Xen on x86
uses its own mechanism to account for the "stolen" time a thread wasn't
able to run due to hypervisor scheduling.

Add support in Xen arch independent time handling for this feature by
moving it out of the arm arch into drivers/xen and remove the x86 Xen
hack.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Replace explicit computation of vma page count by a call to
vma_pages().
Signed-off-by: NMuhammad Falak R Wani <falakreyaz@gmail.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The EFI DT parameters for bare metal are located under /chosen node,
while for Xen Dom0 they are located under /hyperviosr/uefi node. These
parameters under /chosen and /hyperviosr/uefi are not expected to appear
at the same time.

Parse these EFI parameters and initialize EFI like the way for bare
metal except the runtime services because the runtime services for Xen
Dom0 are available through hypercalls and they are always enabled. So it
sets the EFI_RUNTIME_SERVICES flag if it finds /hyperviosr/uefi node and
bails out in arm_enable_runtime_services() when EFI_RUNTIME_SERVICES
flag is set already.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>

Sometimes it needs to check if there is a subnode of given node in FDT
by given name. Introduce this helper to get the subnode if it exists.

CC: Rob Herring <robh@kernel.org>
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NRob Herring <robh@kernel.org>
Tested-by: NJulien Grall <julien.grall@arm.com>

When running on Xen hypervisor, runtime services are supported through
hypercall. Add a Xen specific function to initialize runtime services.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: NJulien Grall <julien.grall@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

Move x86 specific codes to architecture directory and export those EFI
runtime service functions. This will be useful for initializing runtime
service on ARM later.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: NJulien Grall <julien.grall@arm.com>
Signed-off-by: NStefano Stabellini <sstabellini@kernel.org>

Add a "uefi" node under /hypervisor node in FDT, then Linux kernel could
scan this to get the UEFI information.

CC: Rob Herring <robh@kernel.org>
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NRob Herring <robh@kernel.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Move xen_early_init() before efi_init(), then when calling efi_init()
could initialize Xen specific UEFI.

Check if it runs on Xen hypervisor through the flat dts.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

The kernel will get the event-channel IRQ through
HVM_PARAM_CALLBACK_IRQ.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

This new delivery type which is for ARM shares the same value with
HVM_PARAM_CALLBACK_TYPE_VECTOR which is for x86.

val[15:8] is flag: val[7:0] is a PPI.
To the flag, bit 8 stands the interrupt mode is edge(1) or level(0) and
bit 9 stands the interrupt polarity is active low(1) or high(0).
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Sync the changes of HVM_PARAM_CALLBACK_VIA ABI introduced by
Xen commit <ca5c54b6ff05> (public/hvm: export the HVM_PARAM_CALLBACK_VIA
ABI in the API).
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Add a bus_notifier for AMBA bus device in order to map the device
mmio regions when DOM0 booting with ACPI.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Add a bus_notifier for platform bus device in order to map the device
mmio regions when DOM0 booting with ACPI.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Add a new type of Xen map space for Dom0 to map device's MMIO region.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Use xen_xlate_map_ballooned_pages to setup grant table. Then it doesn't
rely on DT or ACPI to pass the start address and size of grant table.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Make xen_xlate_map_ballooned_pages work with 64K pages. In that case
Kernel pages are 64K in size but Xen pages remain 4K in size. Xen pfns
refer to 4K pages.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

Move xlated_setup_gnttab_pages to common place, so it can be reused by
ARM to setup grant table.

Rename it to xen_xlate_map_ballooned_pages.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>

ACPI 6.0 introduces a new table STAO to list the devices which are used
by Xen and can't be used by Dom0. On Xen virtual platforms, the physical
UART is used by Xen. So here it hides UART from Dom0.

CC: "Rafael J. Wysocki" <rjw@rjwysocki.net> (supporter:ACPI)
CC: Len Brown <lenb@kernel.org> (supporter:ACPI)
CC: linux-acpi@vger.kernel.org (open list:ACPI)
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>