linux/arch/powerpc
Paul Mackerras d24ea8a733 KVM: PPC: Book3S: Simplify external interrupt handling
Currently we use two bits in the vcpu pending_exceptions bitmap to
indicate that an external interrupt is pending for the guest, one
for "one-shot" interrupts that are cleared when delivered, and one
for interrupts that persist until cleared by an explicit action of
the OS (e.g. an acknowledge to an interrupt controller).  The
BOOK3S_IRQPRIO_EXTERNAL bit is used for one-shot interrupt requests
and BOOK3S_IRQPRIO_EXTERNAL_LEVEL is used for persisting interrupts.

In practice BOOK3S_IRQPRIO_EXTERNAL never gets used, because our
Book3S platforms generally, and pseries in particular, expect
external interrupt requests to persist until they are acknowledged
at the interrupt controller.  That combined with the confusion
introduced by having two bits for what is essentially the same thing
makes it attractive to simplify things by only using one bit.  This
patch does that.

With this patch there is only BOOK3S_IRQPRIO_EXTERNAL, and by default
it has the semantics of a persisting interrupt.  In order to avoid
breaking the ABI, we introduce a new "external_oneshot" flag which
preserves the behaviour of the KVM_INTERRUPT ioctl with the
KVM_INTERRUPT_SET argument.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09 16:04:27 +11:00
..
boot powerpc updates for 4.19 2018-08-17 11:32:50 -07:00
configs powerpc updates for 4.19 2018-08-17 11:32:50 -07:00
crypto powerpc updates for 4.19 2018-08-17 11:32:50 -07:00
include KVM: PPC: Book3S: Simplify external interrupt handling 2018-10-09 16:04:27 +11:00
kernel powerpc: Turn off CPU_FTR_P9_TM_HV_ASSIST in non-hypervisor mode 2018-10-09 16:04:27 +11:00
kvm KVM: PPC: Book3S: Simplify external interrupt handling 2018-10-09 16:04:27 +11:00
lib powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled 2018-08-10 22:12:35 +10:00
math-emu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm KVM: PPC: Avoid marking DMA-mapped pages dirty in real mode 2018-09-12 08:49:54 +10:00
net powerpc updates for 4.19 2018-08-17 11:32:50 -07:00
oprofile treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
perf powerpc updates for 4.19 2018-08-17 11:32:50 -07:00
platforms Merge branch 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax 2018-08-26 11:48:42 -07:00
purgatory powerpc updates for 4.19 2018-08-17 11:32:50 -07:00
sysdev treewide: correct "differenciate" and "instanciate" typos 2018-08-23 18:48:43 -07:00
tools powerpc: Add a checkpatch wrapper with our preferred settings 2018-08-07 21:49:25 +10:00
xmon Merge branch 'fixes' into next 2018-08-13 15:59:06 +10:00
Kconfig powerpc: disable support for relative ksymtab references 2018-08-29 16:12:07 -07:00
Kconfig.debug Kconfig: consolidate the "Kernel hacking" menu 2018-08-02 08:06:48 +09:00
Makefile kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
Makefile.postlink License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00