entry: Rename "kvm" entry code assets to "virt" to genericize APIs

Rename the "kvm" entry code files and Kconfigs to use generic "virt"
nomenclature so that the code can be reused by other hypervisors (or
rather, their root/dom0 partition drivers), without incorrectly suggesting
the code somehow relies on and/or involves KVM.

No functional change intended.

Signed-off-by: Sean Christopherson <[e-mail]>
Reviewed-by: Thomas Gleixner <[e-mail]>
Reviewed-by: Joel Fernandes <[e-mail]>
Signed-off-by: Wei Liu <[e-mail]>

MAINTAINERS

···
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core/entry
 F:	include/linux/entry-common.h
-F:	include/linux/entry-kvm.h
+F:	include/linux/entry-virt.h
 F:	include/linux/irq-entry-common.h
 F:	kernel/entry/
 

arch/arm64/kvm/Kconfig

···
 	select HAVE_KVM_CPU_RELAX_INTERCEPT
 	select KVM_MMIO
 	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
-	select KVM_XFER_TO_GUEST_WORK
+	select VIRT_XFER_TO_GUEST_WORK
 	select KVM_VFIO
 	select HAVE_KVM_DIRTY_RING_ACQ_REL
 	select NEED_KVM_DIRTY_RING_WITH_BITMAP

arch/loongarch/kvm/Kconfig

···
 	select KVM_GENERIC_HARDWARE_ENABLING
 	select KVM_GENERIC_MMU_NOTIFIER
 	select KVM_MMIO
-	select KVM_XFER_TO_GUEST_WORK
+	select VIRT_XFER_TO_GUEST_WORK
 	select SCHED_INFO
 	select GUEST_PERF_EVENTS if PERF_EVENTS
 	help

arch/riscv/kvm/Kconfig

···
 	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
 	select KVM_GENERIC_HARDWARE_ENABLING
 	select KVM_MMIO
-	select KVM_XFER_TO_GUEST_WORK
+	select VIRT_XFER_TO_GUEST_WORK
 	select KVM_GENERIC_MMU_NOTIFIER
 	select SCHED_INFO
 	select GUEST_PERF_EVENTS if PERF_EVENTS

arch/x86/kvm/Kconfig

···
 	select HAVE_KVM_MSI
 	select HAVE_KVM_CPU_RELAX_INTERCEPT
 	select HAVE_KVM_NO_POLL
-	select KVM_XFER_TO_GUEST_WORK
+	select VIRT_XFER_TO_GUEST_WORK
 	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
 	select KVM_VFIO
 	select HAVE_KVM_PM_NOTIFIER if PM

include/linux/entry-kvm.h include/linux/entry-virt.h

···
 /* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __LINUX_ENTRYKVM_H
-#define __LINUX_ENTRYKVM_H
+#ifndef __LINUX_ENTRYVIRT_H
+#define __LINUX_ENTRYVIRT_H
 
 #include <linux/static_call_types.h>
 #include <linux/resume_user_mode.h>
···
 #include <linux/tick.h>
 
 /* Transfer to guest mode work */
-#ifdef CONFIG_KVM_XFER_TO_GUEST_WORK
+#ifdef CONFIG_VIRT_XFER_TO_GUEST_WORK
 
 #ifndef ARCH_XFER_TO_GUEST_MODE_WORK
 # define ARCH_XFER_TO_GUEST_MODE_WORK	(0)
···
 	lockdep_assert_irqs_disabled();
 	return __xfer_to_guest_mode_work_pending();
 }
-#endif /* CONFIG_KVM_XFER_TO_GUEST_WORK */
+#endif /* CONFIG_VIRT_XFER_TO_GUEST_WORK */
 
 #endif

include/linux/kvm_host.h

···
 #ifndef __KVM_HOST_H
 #define __KVM_HOST_H
 
-#include <linux/entry-kvm.h>
+#include <linux/entry-virt.h>
 #include <linux/types.h>
 #include <linux/hardirq.h>
 #include <linux/list.h>
···
 }
 #endif /* CONFIG_HAVE_KVM_VCPU_RUN_PID_CHANGE */
 
-#ifdef CONFIG_KVM_XFER_TO_GUEST_WORK
+#ifdef CONFIG_VIRT_XFER_TO_GUEST_WORK
 static inline void kvm_handle_signal_exit(struct kvm_vcpu *vcpu)
 {
 	vcpu->run->exit_reason = KVM_EXIT_INTR;
···
 	}
 	return r;
 }
-#endif /* CONFIG_KVM_XFER_TO_GUEST_WORK */
+#endif /* CONFIG_VIRT_XFER_TO_GUEST_WORK */
 
 /*
  * If more than one page is being (un)accounted, @virt must be the address of

include/linux/rcupdate.h

···
 static inline void rcu_sysrq_end(void) { }
 #endif /* #else #ifdef CONFIG_RCU_STALL_COMMON */
 
-#if defined(CONFIG_NO_HZ_FULL) && (!defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_KVM_XFER_TO_GUEST_WORK))
+#if defined(CONFIG_NO_HZ_FULL) && (!defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_VIRT_XFER_TO_GUEST_WORK))
 void rcu_irq_work_resched(void);
 #else
 static __always_inline void rcu_irq_work_resched(void) { }

kernel/entry/Makefile

···
 
 obj-$(CONFIG_GENERIC_IRQ_ENTRY) 	+= common.o
 obj-$(CONFIG_GENERIC_SYSCALL) 		+= syscall-common.o syscall_user_dispatch.o
-obj-$(CONFIG_KVM_XFER_TO_GUEST_WORK)	+= kvm.o
+obj-$(CONFIG_VIRT_XFER_TO_GUEST_WORK)	+= virt.o

kernel/entry/kvm.c kernel/entry/virt.c

···
 // SPDX-License-Identifier: GPL-2.0
 
-#include <linux/entry-kvm.h>
+#include <linux/entry-virt.h>
 
 static int xfer_to_guest_mode_work(unsigned long ti_work)
 {

kernel/rcu/tree.c

···
 }
 EXPORT_SYMBOL_GPL(rcutorture_format_gp_seqs);
 
-#if defined(CONFIG_NO_HZ_FULL) && (!defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_KVM_XFER_TO_GUEST_WORK))
+#if defined(CONFIG_NO_HZ_FULL) && (!defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_VIRT_XFER_TO_GUEST_WORK))
 /*
  * An empty function that will trigger a reschedule on
  * IRQ tail once IRQs get re-enabled on userspace/guest resume.
···
 	if (IS_ENABLED(CONFIG_GENERIC_ENTRY) && !(current->flags & PF_VCPU))
 		return;
 
-	if (IS_ENABLED(CONFIG_KVM_XFER_TO_GUEST_WORK) && (current->flags & PF_VCPU))
+	if (IS_ENABLED(CONFIG_VIRT_XFER_TO_GUEST_WORK) && (current->flags & PF_VCPU))
 		return;
 
 	instrumentation_begin();
···
 	}
 	instrumentation_end();
 }
-#endif /* #if defined(CONFIG_NO_HZ_FULL) && (!defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_KVM_XFER_TO_GUEST_WORK)) */
+#endif /* #if defined(CONFIG_NO_HZ_FULL) && (!defined(CONFIG_GENERIC_ENTRY) || !defined(CONFIG_VIRT_XFER_TO_GUEST_WORK)) */
 
 #ifdef CONFIG_PROVE_RCU
 /**

virt/kvm/Kconfig

···
 config HAVE_KVM_NO_POLL
        bool
 
-config KVM_XFER_TO_GUEST_WORK
+config VIRT_XFER_TO_GUEST_WORK
        bool
 
 config HAVE_KVM_PM_NOTIFIER