[patch V9 31/39] x86/entry: Convert XEN hypercall vector to IDTENTRY_SYSVEC

From: Thomas Gleixner
Date: Thu May 21 2020 - 16:32:50 EST


From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Convert the last oldstyle defined vector to IDTENTRY_SYSVEC
- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64bit
- Remove the BUILD_INTERRUPT entries in 32bit
- Remove the old prototypes

Fixup the related XEN code by providing the primary C entry point in x86 to
avoid cluttering the generic code with X86'isms.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/entry/entry_32.S | 5 -----
arch/x86/entry/entry_64.S | 5 -----
arch/x86/include/asm/idtentry.h | 4 ++++
arch/x86/xen/enlighten_hvm.c | 12 ++++++++++++
drivers/xen/events/events_base.c | 6 ++----
include/xen/events.h | 7 -------
6 files changed, 18 insertions(+), 21 deletions(-)

--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1337,11 +1337,6 @@ SYM_FUNC_START(xen_failsafe_callback)
SYM_FUNC_END(xen_failsafe_callback)
#endif /* CONFIG_XEN_PV */

-#ifdef CONFIG_XEN_PVHVM
-BUILD_INTERRUPT3(xen_hvm_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
- xen_evtchn_do_upcall)
-#endif
-
SYM_CODE_START_LOCAL_NOALIGN(handle_exception)
/* the function address is in %gs's slot on the stack */
SAVE_ALL switch_stacks=1 skip_gs=1 unwind_espfix=1
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1111,11 +1111,6 @@ SYM_CODE_START(xen_failsafe_callback)
SYM_CODE_END(xen_failsafe_callback)
#endif /* CONFIG_XEN_PV */

-#ifdef CONFIG_XEN_PVHVM
-apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
- xen_hvm_callback_vector xen_evtchn_do_upcall
-#endif
-
/*
* Save all registers in pt_regs, and switch gs if needed.
* Use slow, but surefire "are we in kernel?" check.
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -618,6 +618,10 @@ DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_STIME
DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR, sysvec_acrn_hv_callback);
#endif

+#ifdef CONFIG_XEN_PVHVM
+DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR, sysvec_xen_hvm_callback);
+#endif
+
#undef X86_TRAP_OTHER

#endif
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -13,6 +13,7 @@
#include <asm/smp.h>
#include <asm/reboot.h>
#include <asm/setup.h>
+#include <asm/idtentry.h>
#include <asm/hypervisor.h>
#include <asm/e820/api.h>
#include <asm/early_ioremap.h>
@@ -118,6 +119,17 @@ static void __init init_hvm_pv_info(void
this_cpu_write(xen_vcpu_id, smp_processor_id());
}

+DEFINE_IDTENTRY_SYSVEC(sysvec_xen_hvm_callback)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ inc_irq_stat(irq_hv_callback_count);
+
+ xen_hvm_evtchn_do_upcall();
+
+ set_irq_regs(old_regs);
+}
+
#ifdef CONFIG_KEXEC_CORE
static void xen_hvm_shutdown(void)
{
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -37,6 +37,7 @@
#ifdef CONFIG_X86
#include <asm/desc.h>
#include <asm/ptrace.h>
+#include <asm/idtentry.h>
#include <asm/irq.h>
#include <asm/io_apic.h>
#include <asm/i8259.h>
@@ -1236,9 +1237,6 @@ void xen_evtchn_do_upcall(struct pt_regs
struct pt_regs *old_regs = set_irq_regs(regs);

irq_enter();
-#ifdef CONFIG_X86
- inc_irq_stat(irq_hv_callback_count);
-#endif

__xen_evtchn_do_upcall();

@@ -1658,7 +1656,7 @@ static __init void xen_alloc_callback_ve
return;

pr_info("Xen HVM callback vector for event delivery is enabled\n");
- alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, xen_hvm_callback_vector);
+ alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_xen_hvm_callback);
}
#else
void xen_setup_callback_vector(void) {}
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -90,13 +90,6 @@ unsigned int irq_from_evtchn(evtchn_port
int irq_from_virq(unsigned int cpu, unsigned int virq);
evtchn_port_t evtchn_from_irq(unsigned irq);

-#ifdef CONFIG_XEN_PVHVM
-/* Xen HVM evtchn vector callback */
-void xen_hvm_callback_vector(void);
-#ifdef CONFIG_TRACING
-#define trace_xen_hvm_callback_vector xen_hvm_callback_vector
-#endif
-#endif
int xen_set_callback_via(uint64_t via);
void xen_evtchn_do_upcall(struct pt_regs *regs);
void xen_hvm_evtchn_do_upcall(void);