[v3,09/26] iommu, x86: define irq_remapping_cap()

Commit Message

Wu, Feng Dec. 12, 2014, 3:14 p.m. UTC

This patch adds a new interface irq_remapping_cap() to detect
whether irq remapping supports new features, such as VT-d
Posted-Interrupts. We export this function out, so that KVM
code can check this and use this mechanism properly.

Signed-off-by: Feng Wu <[e-mail]>
Reviewed-by: Jiang Liu <[e-mail]>
---
 arch/x86/include/asm/irq_remapping.h |  2 ++
 drivers/iommu/irq_remapping.c        | 12 ++++++++++++
 2 files changed, 14 insertions(+)

Patch

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index f87ac70..b3ad067 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -37,6 +37,7 @@  enum irq_remap_cap {
 
 extern void setup_irq_remapping_ops(void);
 extern int irq_remapping_supported(void);
+extern bool irq_remapping_cap(enum irq_remap_cap cap);
 extern void set_irq_remapping_broken(void);
 extern int irq_remapping_prepare(void);
 extern int irq_remapping_enable(void);
@@ -69,6 +70,7 @@  struct vcpu_data {
 
 static inline void setup_irq_remapping_ops(void) { }
 static inline int irq_remapping_supported(void) { return 0; }
+static bool irq_remapping_cap(enum irq_remap_cap cap) { return 0; }
 static inline void set_irq_remapping_broken(void) { }
 static inline int irq_remapping_prepare(void) { return -ENODEV; }
 static inline int irq_remapping_enable(void) { return -ENODEV; }
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index e63e969..b008663 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -103,6 +103,18 @@  int irq_remapping_supported(void)
 	return remap_ops->supported();
 }
 
+bool irq_remapping_cap(enum irq_remap_cap cap)
+{
+	if (disable_irq_post)
+		return 0;
+
+	if (!remap_ops || !remap_ops->capability)
+		return 0;
+
+	return remap_ops->capability(cap);
+}
+EXPORT_SYMBOL_GPL(irq_remapping_cap);
+
 int __init irq_remapping_prepare(void)
 {
 	if (!remap_ops || !remap_ops->prepare)