[PATCH v4 10/15] x86: hyperv: Add mshv_handler irq handler and setup function

[Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>]

This will handle SYNIC interrupts such as intercepts, doorbells, and
scheduling messages intended for the mshv driver.

Signed-off-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Wei Liu <wei.liu@xxxxxxxxxx>
Reviewed-by: Tianyu Lan <tiala@xxxxxxxxxxxxx>
---
 arch/x86/kernel/cpu/mshyperv.c | 9 +++++++++
 drivers/hv/hv_common.c         | 5 +++++
 include/asm-generic/mshyperv.h | 2 ++
 3 files changed, 16 insertions(+)

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 9b898b65a013..06f79963add5 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -110,6 +110,7 @@ void hv_set_register(unsigned int reg, u64 value)
 }
 EXPORT_SYMBOL_GPL(hv_set_register);
 
+static void (*mshv_handler)(void);
 static void (*vmbus_handler)(void);
 static void (*hv_stimer0_handler)(void);
 static void (*hv_kexec_handler)(void);
@@ -120,6 +121,9 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_callback)
 	struct pt_regs *old_regs = set_irq_regs(regs);
 
 	inc_irq_stat(irq_hv_callback_count);
+	if (mshv_handler)
+		mshv_handler();
+
 	if (vmbus_handler)
 		vmbus_handler();
 
@@ -129,6 +133,11 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_callback)
 	set_irq_regs(old_regs);
 }
 
+void hv_setup_mshv_irq(void (*handler)(void))
+{
+	mshv_handler = handler;
+}
+
 void hv_setup_vmbus_handler(void (*handler)(void))
 {
 	vmbus_handler = handler;
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 3f6f23e4c579..6ec63502d83d 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -585,6 +585,11 @@ void __weak hv_remove_vmbus_handler(void)
 }
 EXPORT_SYMBOL_GPL(hv_remove_vmbus_handler);
 
+void __weak hv_setup_mshv_irq(void (*handler)(void))
+{
+}
+EXPORT_SYMBOL_GPL(hv_setup_mshv_irq);
+
 void __weak hv_setup_kexec_handler(void (*handler)(void))
 {
 }
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 4e49fd662b2b..d832852d0ee7 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -198,6 +198,8 @@ void hv_remove_vmbus_handler(void);
 void hv_setup_stimer0_handler(void (*handler)(void));
 void hv_remove_stimer0_handler(void);
 
+void hv_setup_mshv_irq(void (*handler)(void));
+
 void hv_setup_kexec_handler(void (*handler)(void));
 void hv_remove_kexec_handler(void);
 void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
-- 
2.25.1