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-rw-r--r--arch/mips/kvm/emulate.c89
-rw-r--r--arch/mips/kvm/interrupt.h1
-rw-r--r--arch/mips/kvm/locore.S1
-rw-r--r--arch/mips/kvm/mips.c13
-rw-r--r--arch/mips/kvm/trap_emul.c2
5 files changed, 64 insertions, 42 deletions
diff --git a/arch/mips/kvm/emulate.c b/arch/mips/kvm/emulate.c
index 838d3a6a5b7d..824be0da92cd 100644
--- a/arch/mips/kvm/emulate.c
+++ b/arch/mips/kvm/emulate.c
@@ -302,12 +302,31 @@ static inline ktime_t kvm_mips_count_time(struct kvm_vcpu *vcpu)
*/
static uint32_t kvm_mips_read_count_running(struct kvm_vcpu *vcpu, ktime_t now)
{
- ktime_t expires;
+ struct mips_coproc *cop0 = vcpu->arch.cop0;
+ ktime_t expires, threshold;
+ uint32_t count, compare;
int running;
- /* Is the hrtimer pending? */
+ /* Calculate the biased and scaled guest CP0_Count */
+ count = vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
+ compare = kvm_read_c0_guest_compare(cop0);
+
+ /*
+ * Find whether CP0_Count has reached the closest timer interrupt. If
+ * not, we shouldn't inject it.
+ */
+ if ((int32_t)(count - compare) < 0)
+ return count;
+
+ /*
+ * The CP0_Count we're going to return has already reached the closest
+ * timer interrupt. Quickly check if it really is a new interrupt by
+ * looking at whether the interval until the hrtimer expiry time is
+ * less than 1/4 of the timer period.
+ */
expires = hrtimer_get_expires(&vcpu->arch.comparecount_timer);
- if (ktime_compare(now, expires) >= 0) {
+ threshold = ktime_add_ns(now, vcpu->arch.count_period / 4);
+ if (ktime_before(expires, threshold)) {
/*
* Cancel it while we handle it so there's no chance of
* interference with the timeout handler.
@@ -329,8 +348,7 @@ static uint32_t kvm_mips_read_count_running(struct kvm_vcpu *vcpu, ktime_t now)
}
}
- /* Return the biased and scaled guest CP0_Count */
- return vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
+ return count;
}
/**
@@ -420,32 +438,6 @@ static void kvm_mips_resume_hrtimer(struct kvm_vcpu *vcpu,
}
/**
- * kvm_mips_update_hrtimer() - Update next expiry time of hrtimer.
- * @vcpu: Virtual CPU.
- *
- * Recalculates and updates the expiry time of the hrtimer. This can be used
- * after timer parameters have been altered which do not depend on the time that
- * the change occurs (in those cases kvm_mips_freeze_hrtimer() and
- * kvm_mips_resume_hrtimer() are used directly).
- *
- * It is guaranteed that no timer interrupts will be lost in the process.
- *
- * Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
- */
-static void kvm_mips_update_hrtimer(struct kvm_vcpu *vcpu)
-{
- ktime_t now;
- uint32_t count;
-
- /*
- * freeze_hrtimer takes care of a timer interrupts <= count, and
- * resume_hrtimer the hrtimer takes care of a timer interrupts > count.
- */
- now = kvm_mips_freeze_hrtimer(vcpu, &count);
- kvm_mips_resume_hrtimer(vcpu, now, count);
-}
-
-/**
* kvm_mips_write_count() - Modify the count and update timer.
* @vcpu: Virtual CPU.
* @count: Guest CP0_Count value to set.
@@ -540,23 +532,42 @@ int kvm_mips_set_count_hz(struct kvm_vcpu *vcpu, s64 count_hz)
* kvm_mips_write_compare() - Modify compare and update timer.
* @vcpu: Virtual CPU.
* @compare: New CP0_Compare value.
+ * @ack: Whether to acknowledge timer interrupt.
*
* Update CP0_Compare to a new value and update the timeout.
+ * If @ack, atomically acknowledge any pending timer interrupt, otherwise ensure
+ * any pending timer interrupt is preserved.
*/
-void kvm_mips_write_compare(struct kvm_vcpu *vcpu, uint32_t compare)
+void kvm_mips_write_compare(struct kvm_vcpu *vcpu, uint32_t compare, bool ack)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
+ int dc;
+ u32 old_compare = kvm_read_c0_guest_compare(cop0);
+ ktime_t now;
+ uint32_t count;
/* if unchanged, must just be an ack */
- if (kvm_read_c0_guest_compare(cop0) == compare)
+ if (old_compare == compare) {
+ if (!ack)
+ return;
+ kvm_mips_callbacks->dequeue_timer_int(vcpu);
+ kvm_write_c0_guest_compare(cop0, compare);
return;
+ }
+
+ /* freeze_hrtimer() takes care of timer interrupts <= count */
+ dc = kvm_mips_count_disabled(vcpu);
+ if (!dc)
+ now = kvm_mips_freeze_hrtimer(vcpu, &count);
+
+ if (ack)
+ kvm_mips_callbacks->dequeue_timer_int(vcpu);
- /* Update compare */
kvm_write_c0_guest_compare(cop0, compare);
- /* Update timeout if count enabled */
- if (!kvm_mips_count_disabled(vcpu))
- kvm_mips_update_hrtimer(vcpu);
+ /* resume_hrtimer() takes care of timer interrupts > count */
+ if (!dc)
+ kvm_mips_resume_hrtimer(vcpu, now, count);
}
/**
@@ -1017,9 +1028,9 @@ enum emulation_result kvm_mips_emulate_CP0(uint32_t inst, uint32_t *opc,
/* If we are writing to COMPARE */
/* Clear pending timer interrupt, if any */
- kvm_mips_callbacks->dequeue_timer_int(vcpu);
kvm_mips_write_compare(vcpu,
- vcpu->arch.gprs[rt]);
+ vcpu->arch.gprs[rt],
+ true);
} else if ((rd == MIPS_CP0_STATUS) && (sel == 0)) {
kvm_write_c0_guest_status(cop0,
vcpu->arch.gprs[rt]);
diff --git a/arch/mips/kvm/interrupt.h b/arch/mips/kvm/interrupt.h
index 4ab4bdfad703..2143884709e4 100644
--- a/arch/mips/kvm/interrupt.h
+++ b/arch/mips/kvm/interrupt.h
@@ -28,6 +28,7 @@
#define MIPS_EXC_MAX 12
/* XXXSL More to follow */
+extern char __kvm_mips_vcpu_run_end[];
extern char mips32_exception[], mips32_exceptionEnd[];
extern char mips32_GuestException[], mips32_GuestExceptionEnd[];
diff --git a/arch/mips/kvm/locore.S b/arch/mips/kvm/locore.S
index 4a68b176d6e4..21c257579a06 100644
--- a/arch/mips/kvm/locore.S
+++ b/arch/mips/kvm/locore.S
@@ -231,6 +231,7 @@ FEXPORT(__kvm_mips_load_k0k1)
/* Jump to guest */
eret
+EXPORT(__kvm_mips_vcpu_run_end)
VECTOR(MIPSX(exception), unknown)
/* Find out what mode we came from and jump to the proper handler. */
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 39074fb83bad..26059bf34b1a 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -306,6 +306,15 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
memcpy(gebase + offset, mips32_GuestException,
mips32_GuestExceptionEnd - mips32_GuestException);
+#ifdef MODULE
+ offset += mips32_GuestExceptionEnd - mips32_GuestException;
+ memcpy(gebase + offset, (char *)__kvm_mips_vcpu_run,
+ __kvm_mips_vcpu_run_end - (char *)__kvm_mips_vcpu_run);
+ vcpu->arch.vcpu_run = gebase + offset;
+#else
+ vcpu->arch.vcpu_run = __kvm_mips_vcpu_run;
+#endif
+
/* Invalidate the icache for these ranges */
local_flush_icache_range((unsigned long)gebase,
(unsigned long)gebase + ALIGN(size, PAGE_SIZE));
@@ -392,7 +401,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
/* Disable hardware page table walking while in guest */
htw_stop();
- r = __kvm_mips_vcpu_run(run, vcpu);
+ r = vcpu->arch.vcpu_run(run, vcpu);
/* Re-enable HTW before enabling interrupts */
htw_start();
@@ -784,7 +793,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
/* If nothing is dirty, don't bother messing with page tables. */
if (is_dirty) {
- memslot = &kvm->memslots->memslots[log->slot];
+ memslot = id_to_memslot(kvm->memslots, log->slot);
ga = memslot->base_gfn << PAGE_SHIFT;
ga_end = ga + (memslot->npages << PAGE_SHIFT);
diff --git a/arch/mips/kvm/trap_emul.c b/arch/mips/kvm/trap_emul.c
index 4372cc86650c..9bf7b2b83956 100644
--- a/arch/mips/kvm/trap_emul.c
+++ b/arch/mips/kvm/trap_emul.c
@@ -449,7 +449,7 @@ static int kvm_trap_emul_set_one_reg(struct kvm_vcpu *vcpu,
kvm_mips_write_count(vcpu, v);
break;
case KVM_REG_MIPS_CP0_COMPARE:
- kvm_mips_write_compare(vcpu, v);
+ kvm_mips_write_compare(vcpu, v, false);
break;
case KVM_REG_MIPS_CP0_CAUSE:
/*