[PATCH 08/16] kvm: libkvm: allocate unused gsi for irq routing

From: Sheng Yang <sheng@linux.intel.com>
To: Avi Kivity <avi@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Anthony Liguori <anthony@codemonkey.ws>
Cc: kvm@vger.kernel.org, Sheng Yang <sheng@linux.intel.com>
Subject: [PATCH 08/16] kvm: libkvm: allocate unused gsi for irq routing
Date: Thu, 12 Mar 2009 21:36:51 +0800	[thread overview]
Message-ID: <1236865019-30321-9-git-send-email-sheng@linux.intel.com> (raw)
In-Reply-To: <1236865019-30321-1-git-send-email-sheng@linux.intel.com>

Notice here is a simple solution, can be replaced later.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
---
 libkvm/kvm-common.h |    1 +
 libkvm/libkvm.c     |   15 +++++++++++++++
 libkvm/libkvm.h     |    8 ++++++++
 3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/libkvm/kvm-common.h b/libkvm/kvm-common.h
index de1ada2..70a95c2 100644
--- a/libkvm/kvm-common.h
+++ b/libkvm/kvm-common.h
@@ -66,6 +66,7 @@ struct kvm_context {
 #ifdef KVM_CAP_IRQ_ROUTING
 	struct kvm_irq_routing *irq_routes;
 	int nr_allocated_irq_routes;
+	int max_used_gsi;
 #endif
 };
 
diff --git a/libkvm/libkvm.c b/libkvm/libkvm.c
index e9bae23..405b0bf 100644
--- a/libkvm/libkvm.c
+++ b/libkvm/libkvm.c
@@ -1292,6 +1292,9 @@ int kvm_add_routing_entry(kvm_context_t kvm,
 	new->type = entry->type;
 	new->flags = entry->flags;
 	new->u = entry->u;
+
+	if (entry->gsi > kvm->max_used_gsi)
+		kvm->max_used_gsi = entry->gsi;
 	return 0;
 #else
 	return -ENOSYS;
@@ -1395,3 +1398,15 @@ int kvm_commit_irq_routes(kvm_context_t kvm)
 	return -ENOSYS;
 #endif
 }
+
+int kvm_get_irq_route_gsi(kvm_context_t kvm)
+{
+	if (kvm->max_used_gsi >= KVM_IOAPIC_NUM_PINS)  {
+	    if (kvm->max_used_gsi <= kvm_get_gsi_count(kvm)) 
+                return kvm->max_used_gsi + 1;
+            else
+                return -ENOSPC;
+        } else
+            return KVM_IOAPIC_NUM_PINS;
+}
+
diff --git a/libkvm/libkvm.h b/libkvm/libkvm.h
index 51f4d08..9a7cbc6 100644
--- a/libkvm/libkvm.h
+++ b/libkvm/libkvm.h
@@ -846,4 +846,12 @@ int kvm_del_routing_entry(kvm_context_t kvm,
  */
 int kvm_commit_irq_routes(kvm_context_t kvm);
 
+/*!
+ * \brief Get unused GSI number for irq routing table
+ *
+ * Get unused GSI number for irq routing table
+ *
+ * \param kvm Pointer to the current kvm_context
+ */
+int kvm_get_irq_route_gsi(kvm_context_t kvm);
 #endif
-- 
1.5.4.5

