[patch 3/4] KVM: introduce irq_lock, use it to protect ioapic

Marcelo Tosatti
2009-06-04T18:12:48Z

[-- Attachment #1: ioapic-lock --]
[-- Type: text/plain, Size: 2658 bytes --]

Introduce irq_lock, and use to protect ioapic data structures.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: kvm/include/linux/kvm_host.h
===================================================================
--- kvm.orig/include/linux/kvm_host.h
+++ kvm/include/linux/kvm_host.h
@@ -123,7 +123,6 @@ struct kvm_kernel_irq_routing_entry {
};

struct kvm {
- struct mutex lock; /* protects the vcpus array and APIC accesses */
spinlock_t mmu_lock;
struct rw_semaphore slots_lock;
struct mm_struct *mm; /* userspace tied to this vm */
@@ -132,6 +131,7 @@ struct kvm {
KVM_PRIVATE_MEM_SLOTS];
struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
struct list_head vm_list;
+ struct mutex lock;
struct kvm_io_bus mmio_bus;
struct kvm_io_bus pio_bus;
#ifdef CONFIG_HAVE_KVM_EVENTFD
@@ -145,6 +145,7 @@ struct kvm {
struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
#endif

+ struct mutex irq_lock;
#ifdef CONFIG_HAVE_KVM_IRQCHIP
struct list_head irq_routing; /* of kvm_kernel_irq_routing_entry */
struct hlist_head mask_notifier_list;
Index: kvm/virt/kvm/ioapic.c
===================================================================
--- kvm.orig/virt/kvm/ioapic.c
+++ kvm/virt/kvm/ioapic.c
@@ -243,6 +243,7 @@ static void ioapic_mmio_read(struct kvm_
ioapic_debug("addr %lx\n", (unsigned long)addr);
ASSERT(!(addr & 0xf)); /* check alignment */

+ mutex_lock(&ioapic->kvm->irq_lock);
addr &= 0xff;
switch (addr) {
case IOAPIC_REG_SELECT:
@@ -269,6 +270,7 @@ static void ioapic_mmio_read(struct kvm_
default:
printk(KERN_WARNING "ioapic: wrong length %d\n", len);
}
+ mutex_unlock(&ioapic->kvm->irq_lock);
}

static void ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
@@ -280,6 +282,8 @@ static void ioapic_mmio_write(struct kvm
ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
(void*)addr, len, val);
ASSERT(!(addr & 0xf)); /* check alignment */
+
+ mutex_lock(&ioapic->kvm->irq_lock);
if (len == 4 || len == 8)
data = *(u32 *) val;
else {
@@ -305,6 +309,7 @@ static void ioapic_mmio_write(struct kvm
default:
break;
}
+ mutex_unlock(&ioapic->kvm->irq_lock);
}

void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
Index: kvm/virt/kvm/kvm_main.c
===================================================================
--- kvm.orig/virt/kvm/kvm_main.c
+++ kvm/virt/kvm/kvm_main.c
@@ -979,6 +979,7 @@ static struct kvm *kvm_create_vm(void)
kvm_io_bus_init(&kvm->pio_bus);
kvm_irqfd_init(kvm);
mutex_init(&kvm->lock);
+ mutex_init(&kvm->irq_lock);
kvm_io_bus_init(&kvm->mmio_bus);
init_rwsem(&kvm->slots_lock);
atomic_set(&kvm->users_count, 1);

--