KVM: cleanup io_device code

We modernize the io_device code so that we use container_of() instead of
dev->private, and move the vtable to a separate ops structure
(theoretically allows better caching for multiple instances of the same
ops structure)

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Avi Kivity <avi@redhat.com>

4 files changed, 58 insertions, 26 deletions

diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 0990bc9aac1f..e800d2d66266 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -350,10 +350,20 @@ void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val)
         mutex_unlock(&kvm->arch.vpit->pit_state.lock);
 }
 
+static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev)
+{
+        return container_of(dev, struct kvm_pit, dev);
+}
+
+static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev)
+{
+        return container_of(dev, struct kvm_pit, speaker_dev);
+}
+
 static void pit_ioport_write(struct kvm_io_device *this,
                              gpa_t addr, int len, const void *data)
 {
-        struct kvm_pit *pit = (struct kvm_pit *)this->private;
+        struct kvm_pit *pit = dev_to_pit(this);
         struct kvm_kpit_state *pit_state = &pit->pit_state;
         struct kvm *kvm = pit->kvm;
         int channel, access;
@@ -426,7 +436,7 @@ static void pit_ioport_write(struct kvm_io_device *this,
 static void pit_ioport_read(struct kvm_io_device *this,
                             gpa_t addr, int len, void *data)
 {
-        struct kvm_pit *pit = (struct kvm_pit *)this->private;
+        struct kvm_pit *pit = dev_to_pit(this);
         struct kvm_kpit_state *pit_state = &pit->pit_state;
         struct kvm *kvm = pit->kvm;
         int ret, count;
@@ -497,7 +507,7 @@ static int pit_in_range(struct kvm_io_device *this, gpa_t addr,
 static void speaker_ioport_write(struct kvm_io_device *this,
                                  gpa_t addr, int len, const void *data)
 {
-        struct kvm_pit *pit = (struct kvm_pit *)this->private;
+        struct kvm_pit *pit = speaker_to_pit(this);
         struct kvm_kpit_state *pit_state = &pit->pit_state;
         struct kvm *kvm = pit->kvm;
         u32 val = *(u32 *) data;
@@ -511,7 +521,7 @@ static void speaker_ioport_write(struct kvm_io_device *this,
 static void speaker_ioport_read(struct kvm_io_device *this,
                                 gpa_t addr, int len, void *data)
 {
-        struct kvm_pit *pit = (struct kvm_pit *)this->private;
+        struct kvm_pit *pit = speaker_to_pit(this);
         struct kvm_kpit_state *pit_state = &pit->pit_state;
         struct kvm *kvm = pit->kvm;
         unsigned int refresh_clock;
@@ -563,6 +573,18 @@ static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
         }
 }
 
+static const struct kvm_io_device_ops pit_dev_ops = {
+        .read     = pit_ioport_read,
+        .write    = pit_ioport_write,
+        .in_range = pit_in_range,
+};
+
+static const struct kvm_io_device_ops speaker_dev_ops = {
+        .read     = speaker_ioport_read,
+        .write    = speaker_ioport_write,
+        .in_range = speaker_in_range,
+};
+
 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
 {
         struct kvm_pit *pit;
@@ -583,17 +605,11 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
         spin_lock_init(&pit->pit_state.inject_lock);
 
         /* Initialize PIO device */
-        pit->dev.read = pit_ioport_read;
-        pit->dev.write = pit_ioport_write;
-        pit->dev.in_range = pit_in_range;
-        pit->dev.private = pit;
+        kvm_iodevice_init(&pit->dev, &pit_dev_ops);
         kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev);
 
         if (flags & KVM_PIT_SPEAKER_DUMMY) {
-                pit->speaker_dev.read = speaker_ioport_read;
-                pit->speaker_dev.write = speaker_ioport_write;
-                pit->speaker_dev.in_range = speaker_in_range;
-                pit->speaker_dev.private = pit;
+                kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
                 kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev);
         }
 
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 1ccb50c74f18..2520922282d5 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -444,10 +444,15 @@ static int picdev_in_range(struct kvm_io_device *this, gpa_t addr,
         }
 }
 
+static inline struct kvm_pic *to_pic(struct kvm_io_device *dev)
+{
+        return container_of(dev, struct kvm_pic, dev);
+}
+
 static void picdev_write(struct kvm_io_device *this,
                          gpa_t addr, int len, const void *val)
 {
-        struct kvm_pic *s = this->private;
+        struct kvm_pic *s = to_pic(this);
         unsigned char data = *(unsigned char *)val;
 
         if (len != 1) {
@@ -474,7 +479,7 @@ static void picdev_write(struct kvm_io_device *this,
 static void picdev_read(struct kvm_io_device *this,
                         gpa_t addr, int len, void *val)
 {
-        struct kvm_pic *s = this->private;
+        struct kvm_pic *s = to_pic(this);
         unsigned char data = 0;
 
         if (len != 1) {
@@ -516,6 +521,12 @@ static void pic_irq_request(void *opaque, int level)
         }
 }
 
+static const struct kvm_io_device_ops picdev_ops = {
+        .read     = picdev_read,
+        .write    = picdev_write,
+        .in_range = picdev_in_range,
+};
+
 struct kvm_pic *kvm_create_pic(struct kvm *kvm)
 {
         struct kvm_pic *s;
@@ -534,10 +545,7 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
         /*
          * Initialize PIO device
          */
-        s->dev.read = picdev_read;
-        s->dev.write = picdev_write;
-        s->dev.in_range = picdev_in_range;
-        s->dev.private = s;
+        kvm_iodevice_init(&s->dev, &picdev_ops);
         kvm_io_bus_register_dev(&kvm->pio_bus, &s->dev);
         return s;
 }
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ae99d83f81a3..4bfd458a4f3e 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -522,10 +522,15 @@ static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
         return val;
 }
 
+static inline struct kvm_lapic *to_lapic(struct kvm_io_device *dev)
+{
+        return container_of(dev, struct kvm_lapic, dev);
+}
+
 static void apic_mmio_read(struct kvm_io_device *this,
                            gpa_t address, int len, void *data)
 {
-        struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
+        struct kvm_lapic *apic = to_lapic(this);
         unsigned int offset = address - apic->base_address;
         unsigned char alignment = offset & 0xf;
         u32 result;
@@ -606,7 +611,7 @@ static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
 static void apic_mmio_write(struct kvm_io_device *this,
                             gpa_t address, int len, const void *data)
 {
-        struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
+        struct kvm_lapic *apic = to_lapic(this);
         unsigned int offset = address - apic->base_address;
         unsigned char alignment = offset & 0xf;
         u32 val;
@@ -723,7 +728,7 @@ static void apic_mmio_write(struct kvm_io_device *this,
 static int apic_mmio_range(struct kvm_io_device *this, gpa_t addr,
                            int len, int size)
 {
-        struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
+        struct kvm_lapic *apic = to_lapic(this);
         int ret = 0;
 
 
@@ -917,6 +922,12 @@ static struct kvm_timer_ops lapic_timer_ops = {
         .is_periodic = lapic_is_periodic,
 };
 
+static const struct kvm_io_device_ops apic_mmio_ops = {
+        .read     = apic_mmio_read,
+        .write    = apic_mmio_write,
+        .in_range = apic_mmio_range,
+};
+
 int kvm_create_lapic(struct kvm_vcpu *vcpu)
 {
         struct kvm_lapic *apic;
@@ -951,10 +962,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu)
         vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE;
 
         kvm_lapic_reset(vcpu);
-        apic->dev.read = apic_mmio_read;
-        apic->dev.write = apic_mmio_write;
-        apic->dev.in_range = apic_mmio_range;
-        apic->dev.private = apic;
+        kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
 
         return 0;
 nomem_free_apic:
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5eb3b8dd74b8..75e9df097845 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2264,7 +2264,7 @@ static struct kvm_io_device *vcpu_find_pervcpu_dev(struct kvm_vcpu *vcpu,
 
         if (vcpu->arch.apic) {
                 dev = &vcpu->arch.apic->dev;
-                if (dev->in_range(dev, addr, len, is_write))
+                if (kvm_iodevice_in_range(dev, addr, len, is_write))
                         return dev;
         }
         return NULL;