KVM: Trace exception injection
[safe/jmp/linux-2.6] / arch / x86 / kvm / i8259.c
index 148c52a..93825ff 100644 (file)
  *   Port from Qemu.
  */
 #include <linux/mm.h>
+#include <linux/slab.h>
 #include <linux/bitops.h>
 #include "irq.h"
 
 #include <linux/kvm_host.h>
+#include "trace.h"
 
 static void pic_lock(struct kvm_pic *s)
        __acquires(&s->lock)
 {
-       spin_lock(&s->lock);
+       raw_spin_lock(&s->lock);
 }
 
 static void pic_unlock(struct kvm_pic *s)
        __releases(&s->lock)
 {
-       struct kvm *kvm = s->kvm;
-       unsigned acks = s->pending_acks;
        bool wakeup = s->wakeup_needed;
        struct kvm_vcpu *vcpu;
 
-       s->pending_acks = 0;
        s->wakeup_needed = false;
 
-       spin_unlock(&s->lock);
-
-       while (acks) {
-               kvm_notify_acked_irq(kvm, SELECT_PIC(__ffs(acks)),
-                                    __ffs(acks));
-               acks &= acks - 1;
-       }
+       raw_spin_unlock(&s->lock);
 
        if (wakeup) {
                vcpu = s->kvm->bsp_vcpu;
@@ -67,11 +60,23 @@ static void pic_clear_isr(struct kvm_kpic_state *s, int irq)
 {
        s->isr &= ~(1 << irq);
        s->isr_ack |= (1 << irq);
+       if (s != &s->pics_state->pics[0])
+               irq += 8;
+       /*
+        * We are dropping lock while calling ack notifiers since ack
+        * notifier callbacks for assigned devices call into PIC recursively.
+        * Other interrupt may be delivered to PIC while lock is dropped but
+        * it should be safe since PIC state is already updated at this stage.
+        */
+       pic_unlock(s->pics_state);
+       kvm_notify_acked_irq(s->pics_state->kvm, SELECT_PIC(irq), irq);
+       pic_lock(s->pics_state);
 }
 
 void kvm_pic_clear_isr_ack(struct kvm *kvm)
 {
        struct kvm_pic *s = pic_irqchip(kvm);
+
        pic_lock(s);
        s->pics[0].isr_ack = 0xff;
        s->pics[1].isr_ack = 0xff;
@@ -190,6 +195,8 @@ int kvm_pic_set_irq(void *opaque, int irq, int level)
        if (irq >= 0 && irq < PIC_NUM_PINS) {
                ret = pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
                pic_update_irq(s);
+               trace_kvm_pic_set_irq(irq >> 3, irq & 7, s->pics[irq >> 3].elcr,
+                                     s->pics[irq >> 3].imr, ret == 0);
        }
        pic_unlock(s);
 
@@ -202,16 +209,18 @@ int kvm_pic_set_irq(void *opaque, int irq, int level)
 static inline void pic_intack(struct kvm_kpic_state *s, int irq)
 {
        s->isr |= 1 << irq;
-       if (s->auto_eoi) {
-               if (s->rotate_on_auto_eoi)
-                       s->priority_add = (irq + 1) & 7;
-               pic_clear_isr(s, irq);
-       }
        /*
         * We don't clear a level sensitive interrupt here
         */
        if (!(s->elcr & (1 << irq)))
                s->irr &= ~(1 << irq);
+
+       if (s->auto_eoi) {
+               if (s->rotate_on_auto_eoi)
+                       s->priority_add = (irq + 1) & 7;
+               pic_clear_isr(s, irq);
+       }
+
 }
 
 int kvm_pic_read_irq(struct kvm *kvm)
@@ -245,29 +254,17 @@ int kvm_pic_read_irq(struct kvm *kvm)
        }
        pic_update_irq(s);
        pic_unlock(s);
-       kvm_notify_acked_irq(kvm, SELECT_PIC(irq), irq);
 
        return intno;
 }
 
 void kvm_pic_reset(struct kvm_kpic_state *s)
 {
-       int irq, irqbase, n;
+       int irq;
        struct kvm *kvm = s->pics_state->irq_request_opaque;
        struct kvm_vcpu *vcpu0 = kvm->bsp_vcpu;
+       u8 irr = s->irr, isr = s->imr;
 
-       if (s == &s->pics_state->pics[0])
-               irqbase = 0;
-       else
-               irqbase = 8;
-
-       for (irq = 0; irq < PIC_NUM_PINS/2; irq++) {
-               if (vcpu0 && kvm_apic_accept_pic_intr(vcpu0))
-                       if (s->irr & (1 << irq) || s->isr & (1 << irq)) {
-                               n = irq + irqbase;
-                               s->pics_state->pending_acks |= 1 << n;
-                       }
-       }
        s->last_irr = 0;
        s->irr = 0;
        s->imr = 0;
@@ -283,6 +280,13 @@ void kvm_pic_reset(struct kvm_kpic_state *s)
        s->rotate_on_auto_eoi = 0;
        s->special_fully_nested_mode = 0;
        s->init4 = 0;
+
+       for (irq = 0; irq < PIC_NUM_PINS/2; irq++) {
+               if (vcpu0 && kvm_apic_accept_pic_intr(vcpu0))
+                       if (irr & (1 << irq) || isr & (1 << irq)) {
+                               pic_clear_isr(s, irq);
+                       }
+       }
 }
 
 static void pic_ioport_write(void *opaque, u32 addr, u32 val)
@@ -325,9 +329,9 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
                                priority = get_priority(s, s->isr);
                                if (priority != 8) {
                                        irq = (priority + s->priority_add) & 7;
-                                       pic_clear_isr(s, irq);
                                        if (cmd == 5)
                                                s->priority_add = (irq + 1) & 7;
+                                       pic_clear_isr(s, irq);
                                        pic_update_irq(s->pics_state);
                                }
                                break;
@@ -430,8 +434,7 @@ static u32 elcr_ioport_read(void *opaque, u32 addr1)
        return s->elcr;
 }
 
-static int picdev_in_range(struct kvm_io_device *this, gpa_t addr,
-                          int len, int is_write)
+static int picdev_in_range(gpa_t addr)
 {
        switch (addr) {
        case 0x20:
@@ -451,16 +454,18 @@ 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,
+static int picdev_write(struct kvm_io_device *this,
                         gpa_t addr, int len, const void *val)
 {
        struct kvm_pic *s = to_pic(this);
        unsigned char data = *(unsigned char *)val;
+       if (!picdev_in_range(addr))
+               return -EOPNOTSUPP;
 
        if (len != 1) {
                if (printk_ratelimit())
                        printk(KERN_ERR "PIC: non byte write\n");
-               return;
+               return 0;
        }
        pic_lock(s);
        switch (addr) {
@@ -476,18 +481,21 @@ static void picdev_write(struct kvm_io_device *this,
                break;
        }
        pic_unlock(s);
+       return 0;
 }
 
-static void picdev_read(struct kvm_io_device *this,
-                       gpa_t addr, int len, void *val)
+static int picdev_read(struct kvm_io_device *this,
+                      gpa_t addr, int len, void *val)
 {
        struct kvm_pic *s = to_pic(this);
        unsigned char data = 0;
+       if (!picdev_in_range(addr))
+               return -EOPNOTSUPP;
 
        if (len != 1) {
                if (printk_ratelimit())
                        printk(KERN_ERR "PIC: non byte read\n");
-               return;
+               return 0;
        }
        pic_lock(s);
        switch (addr) {
@@ -504,6 +512,7 @@ static void picdev_read(struct kvm_io_device *this,
        }
        *(unsigned char *)val = data;
        pic_unlock(s);
+       return 0;
 }
 
 /*
@@ -526,16 +535,17 @@ 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;
+       int ret;
+
        s = kzalloc(sizeof(struct kvm_pic), GFP_KERNEL);
        if (!s)
                return NULL;
-       spin_lock_init(&s->lock);
+       raw_spin_lock_init(&s->lock);
        s->kvm = kvm;
        s->pics[0].elcr_mask = 0xf8;
        s->pics[1].elcr_mask = 0xde;
@@ -548,6 +558,24 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
         * Initialize PIO device
         */
        kvm_iodevice_init(&s->dev, &picdev_ops);
-       kvm_io_bus_register_dev(&kvm->pio_bus, &s->dev);
+       mutex_lock(&kvm->slots_lock);
+       ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, &s->dev);
+       mutex_unlock(&kvm->slots_lock);
+       if (ret < 0) {
+               kfree(s);
+               return NULL;
+       }
+
        return s;
 }
+
+void kvm_destroy_pic(struct kvm *kvm)
+{
+       struct kvm_pic *vpic = kvm->arch.vpic;
+
+       if (vpic) {
+               kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &vpic->dev);
+               kvm->arch.vpic = NULL;
+               kfree(vpic);
+       }
+}