KVM: convert slots_lock to a mutex
[safe/jmp/linux-2.6] / virt / kvm / ioapic.c
index 1150c6d..f01392f 100644 (file)
@@ -36,6 +36,7 @@
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/current.h>
+#include <trace/events/kvm.h>
 
 #include "ioapic.h"
 #include "lapic.h"
@@ -103,6 +104,7 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 {
        unsigned index;
        bool mask_before, mask_after;
+       union kvm_ioapic_redirect_entry *e;
 
        switch (ioapic->ioregsel) {
        case IOAPIC_REG_VERSION:
@@ -122,19 +124,20 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
                ioapic_debug("change redir index %x val %x\n", index, val);
                if (index >= IOAPIC_NUM_PINS)
                        return;
-               mask_before = ioapic->redirtbl[index].fields.mask;
+               e = &ioapic->redirtbl[index];
+               mask_before = e->fields.mask;
                if (ioapic->ioregsel & 1) {
-                       ioapic->redirtbl[index].bits &= 0xffffffff;
-                       ioapic->redirtbl[index].bits |= (u64) val << 32;
+                       e->bits &= 0xffffffff;
+                       e->bits |= (u64) val << 32;
                } else {
-                       ioapic->redirtbl[index].bits &= ~0xffffffffULL;
-                       ioapic->redirtbl[index].bits |= (u32) val;
-                       ioapic->redirtbl[index].fields.remote_irr = 0;
+                       e->bits &= ~0xffffffffULL;
+                       e->bits |= (u32) val;
+                       e->fields.remote_irr = 0;
                }
-               mask_after = ioapic->redirtbl[index].fields.mask;
+               mask_after = e->fields.mask;
                if (mask_before != mask_after)
                        kvm_fire_mask_notifiers(ioapic->kvm, index, mask_after);
-               if (ioapic->redirtbl[index].fields.trig_mode == IOAPIC_LEVEL_TRIG
+               if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
                    && ioapic->irr & (1 << index))
                        ioapic_service(ioapic, index);
                break;
@@ -164,7 +167,9 @@ static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
        /* Always delivery PIT interrupt to vcpu 0 */
        if (irq == 0) {
                irqe.dest_mode = 0; /* Physical mode. */
-               irqe.dest_id = ioapic->kvm->vcpus[0]->vcpu_id;
+               /* need to read apic_id from apic regiest since
+                * it can be rewritten */
+               irqe.dest_id = ioapic->kvm->bsp_vcpu->vcpu_id;
        }
 #endif
        return kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe);
@@ -177,6 +182,7 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
        union kvm_ioapic_redirect_entry entry;
        int ret = 1;
 
+       mutex_lock(&ioapic->lock);
        if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
                entry = ioapic->redirtbl[irq];
                level ^= entry.fields.polarity;
@@ -188,57 +194,82 @@ int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
                        if ((edge && old_irr != ioapic->irr) ||
                            (!edge && !entry.fields.remote_irr))
                                ret = ioapic_service(ioapic, irq);
+                       else
+                               ret = 0; /* report coalesced interrupt */
                }
+               trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
        }
+       mutex_unlock(&ioapic->lock);
+
        return ret;
 }
 
-static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int pin,
-                                   int trigger_mode)
+static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int vector,
+                                    int trigger_mode)
 {
-       union kvm_ioapic_redirect_entry *ent;
+       int i;
+
+       for (i = 0; i < IOAPIC_NUM_PINS; i++) {
+               union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
+
+               if (ent->fields.vector != vector)
+                       continue;
 
-       ent = &ioapic->redirtbl[pin];
+               /*
+                * We are dropping lock while calling ack notifiers because ack
+                * notifier callbacks for assigned devices call into IOAPIC
+                * recursively. Since remote_irr is cleared only after call
+                * to notifiers if the same vector will be delivered while lock
+                * is dropped it will be put into irr and will be delivered
+                * after ack notifier returns.
+                */
+               mutex_unlock(&ioapic->lock);
+               kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
+               mutex_lock(&ioapic->lock);
 
-       kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin);
+               if (trigger_mode != IOAPIC_LEVEL_TRIG)
+                       continue;
 
-       if (trigger_mode == IOAPIC_LEVEL_TRIG) {
                ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
                ent->fields.remote_irr = 0;
-               if (!ent->fields.mask && (ioapic->irr & (1 << pin)))
-                       ioapic_service(ioapic, pin);
+               if (!ent->fields.mask && (ioapic->irr & (1 << i)))
+                       ioapic_service(ioapic, i);
        }
 }
 
 void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)
 {
        struct kvm_ioapic *ioapic = kvm->arch.vioapic;
-       int i;
 
-       for (i = 0; i < IOAPIC_NUM_PINS; i++)
-               if (ioapic->redirtbl[i].fields.vector == vector)
-                       __kvm_ioapic_update_eoi(ioapic, i, trigger_mode);
+       mutex_lock(&ioapic->lock);
+       __kvm_ioapic_update_eoi(ioapic, vector, trigger_mode);
+       mutex_unlock(&ioapic->lock);
 }
 
-static int ioapic_in_range(struct kvm_io_device *this, gpa_t addr,
-                          int len, int is_write)
+static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
 {
-       struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private;
+       return container_of(dev, struct kvm_ioapic, dev);
+}
 
+static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
+{
        return ((addr >= ioapic->base_address &&
                 (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
 }
 
-static void ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
-                            void *val)
+static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
+                           void *val)
 {
-       struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private;
+       struct kvm_ioapic *ioapic = to_ioapic(this);
        u32 result;
+       if (!ioapic_in_range(ioapic, addr))
+               return -EOPNOTSUPP;
 
        ioapic_debug("addr %lx\n", (unsigned long)addr);
        ASSERT(!(addr & 0xf));  /* check alignment */
 
        addr &= 0xff;
+       mutex_lock(&ioapic->lock);
        switch (addr) {
        case IOAPIC_REG_SELECT:
                result = ioapic->ioregsel;
@@ -252,6 +283,8 @@ static void ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
                result = 0;
                break;
        }
+       mutex_unlock(&ioapic->lock);
+
        switch (len) {
        case 8:
                *(u64 *) val = result;
@@ -264,25 +297,30 @@ static void ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
        default:
                printk(KERN_WARNING "ioapic: wrong length %d\n", len);
        }
+       return 0;
 }
 
-static void ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
-                             const void *val)
+static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
+                            const void *val)
 {
-       struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private;
+       struct kvm_ioapic *ioapic = to_ioapic(this);
        u32 data;
+       if (!ioapic_in_range(ioapic, addr))
+               return -EOPNOTSUPP;
 
        ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
                     (void*)addr, len, val);
        ASSERT(!(addr & 0xf));  /* check alignment */
+
        if (len == 4 || len == 8)
                data = *(u32 *) val;
        else {
                printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
-               return;
+               return 0;
        }
 
        addr &= 0xff;
+       mutex_lock(&ioapic->lock);
        switch (addr) {
        case IOAPIC_REG_SELECT:
                ioapic->ioregsel = data;
@@ -293,13 +331,15 @@ static void ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
                break;
 #ifdef CONFIG_IA64
        case IOAPIC_REG_EOI:
-               kvm_ioapic_update_eoi(ioapic->kvm, data, IOAPIC_LEVEL_TRIG);
+               __kvm_ioapic_update_eoi(ioapic, data, IOAPIC_LEVEL_TRIG);
                break;
 #endif
 
        default:
                break;
        }
+       mutex_unlock(&ioapic->lock);
+       return 0;
 }
 
 void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
@@ -314,21 +354,53 @@ void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
        ioapic->id = 0;
 }
 
+static const struct kvm_io_device_ops ioapic_mmio_ops = {
+       .read     = ioapic_mmio_read,
+       .write    = ioapic_mmio_write,
+};
+
 int kvm_ioapic_init(struct kvm *kvm)
 {
        struct kvm_ioapic *ioapic;
+       int ret;
 
        ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
        if (!ioapic)
                return -ENOMEM;
+       mutex_init(&ioapic->lock);
        kvm->arch.vioapic = ioapic;
        kvm_ioapic_reset(ioapic);
-       ioapic->dev.read = ioapic_mmio_read;
-       ioapic->dev.write = ioapic_mmio_write;
-       ioapic->dev.in_range = ioapic_in_range;
-       ioapic->dev.private = ioapic;
+       kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
        ioapic->kvm = kvm;
-       kvm_io_bus_register_dev(&kvm->mmio_bus, &ioapic->dev);
+       mutex_lock(&kvm->slots_lock);
+       ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
+       mutex_unlock(&kvm->slots_lock);
+       if (ret < 0)
+               kfree(ioapic);
+
+       return ret;
+}
+
+int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
+{
+       struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
+       if (!ioapic)
+               return -EINVAL;
+
+       mutex_lock(&ioapic->lock);
+       memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
+       mutex_unlock(&ioapic->lock);
        return 0;
 }
 
+int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
+{
+       struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
+       if (!ioapic)
+               return -EINVAL;
+
+       mutex_lock(&ioapic->lock);
+       memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
+       mutex_unlock(&ioapic->lock);
+       return 0;
+}