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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2009-12-09 17:14:38 +1100
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2009-12-09 17:14:38 +1100
commitbcd6acd51f3d4d1ada201e9bc5c40a31d6d80c71 (patch)
tree2f6dffd2d3e4dd67355a224de7e7a960335a92fd /virt/kvm/irq_comm.c
parentMAINTAINERS: Add PowerPC patterns (diff)
parentMerge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip (diff)
downloadlinux-dev-bcd6acd51f3d4d1ada201e9bc5c40a31d6d80c71.tar.xz
linux-dev-bcd6acd51f3d4d1ada201e9bc5c40a31d6d80c71.zip
Merge commit 'origin/master' into next
Conflicts: include/linux/kvm.h
Diffstat (limited to 'virt/kvm/irq_comm.c')
-rw-r--r--virt/kvm/irq_comm.c231
1 files changed, 136 insertions, 95 deletions
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index 001663ff401a..9b077342ab54 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -31,20 +31,39 @@
#include "ioapic.h"
+static inline int kvm_irq_line_state(unsigned long *irq_state,
+ int irq_source_id, int level)
+{
+ /* Logical OR for level trig interrupt */
+ if (level)
+ set_bit(irq_source_id, irq_state);
+ else
+ clear_bit(irq_source_id, irq_state);
+
+ return !!(*irq_state);
+}
+
static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int level)
+ struct kvm *kvm, int irq_source_id, int level)
{
#ifdef CONFIG_X86
- return kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
+ struct kvm_pic *pic = pic_irqchip(kvm);
+ level = kvm_irq_line_state(&pic->irq_states[e->irqchip.pin],
+ irq_source_id, level);
+ return kvm_pic_set_irq(pic, e->irqchip.pin, level);
#else
return -1;
#endif
}
static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int level)
+ struct kvm *kvm, int irq_source_id, int level)
{
- return kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
+ struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+ level = kvm_irq_line_state(&ioapic->irq_states[e->irqchip.pin],
+ irq_source_id, level);
+
+ return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, level);
}
inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
@@ -63,8 +82,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
int i, r = -1;
struct kvm_vcpu *vcpu, *lowest = NULL;
- WARN_ON(!mutex_is_locked(&kvm->irq_lock));
-
if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
kvm_is_dm_lowest_prio(irq))
printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
@@ -96,10 +113,13 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
}
static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int level)
+ struct kvm *kvm, int irq_source_id, int level)
{
struct kvm_lapic_irq irq;
+ if (!level)
+ return -1;
+
trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
irq.dest_id = (e->msi.address_lo &
@@ -116,78 +136,67 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
}
-/* This should be called with the kvm->irq_lock mutex held
+/*
* Return value:
* < 0 Interrupt was ignored (masked or not delivered for other reasons)
* = 0 Interrupt was coalesced (previous irq is still pending)
* > 0 Number of CPUs interrupt was delivered to
*/
-int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
+int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level)
{
- struct kvm_kernel_irq_routing_entry *e;
- unsigned long *irq_state, sig_level;
- int ret = -1;
+ struct kvm_kernel_irq_routing_entry *e, irq_set[KVM_NR_IRQCHIPS];
+ int ret = -1, i = 0;
+ struct kvm_irq_routing_table *irq_rt;
+ struct hlist_node *n;
trace_kvm_set_irq(irq, level, irq_source_id);
- WARN_ON(!mutex_is_locked(&kvm->irq_lock));
-
- if (irq < KVM_IOAPIC_NUM_PINS) {
- irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
-
- /* Logical OR for level trig interrupt */
- if (level)
- set_bit(irq_source_id, irq_state);
- else
- clear_bit(irq_source_id, irq_state);
- sig_level = !!(*irq_state);
- } else if (!level)
- return ret;
- else /* Deal with MSI/MSI-X */
- sig_level = 1;
-
/* Not possible to detect if the guest uses the PIC or the
* IOAPIC. So set the bit in both. The guest will ignore
* writes to the unused one.
*/
- list_for_each_entry(e, &kvm->irq_routing, link)
- if (e->gsi == irq) {
- int r = e->set(e, kvm, sig_level);
- if (r < 0)
- continue;
+ rcu_read_lock();
+ irq_rt = rcu_dereference(kvm->irq_routing);
+ if (irq < irq_rt->nr_rt_entries)
+ hlist_for_each_entry(e, n, &irq_rt->map[irq], link)
+ irq_set[i++] = *e;
+ rcu_read_unlock();
+
+ while(i--) {
+ int r;
+ r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level);
+ if (r < 0)
+ continue;
+
+ ret = r + ((ret < 0) ? 0 : ret);
+ }
- ret = r + ((ret < 0) ? 0 : ret);
- }
return ret;
}
void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
{
- struct kvm_kernel_irq_routing_entry *e;
struct kvm_irq_ack_notifier *kian;
struct hlist_node *n;
- unsigned gsi = pin;
+ int gsi;
trace_kvm_ack_irq(irqchip, pin);
- list_for_each_entry(e, &kvm->irq_routing, link)
- if (e->type == KVM_IRQ_ROUTING_IRQCHIP &&
- e->irqchip.irqchip == irqchip &&
- e->irqchip.pin == pin) {
- gsi = e->gsi;
- break;
- }
-
- hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
- if (kian->gsi == gsi)
- kian->irq_acked(kian);
+ rcu_read_lock();
+ gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
+ if (gsi != -1)
+ hlist_for_each_entry_rcu(kian, n, &kvm->irq_ack_notifier_list,
+ link)
+ if (kian->gsi == gsi)
+ kian->irq_acked(kian);
+ rcu_read_unlock();
}
void kvm_register_irq_ack_notifier(struct kvm *kvm,
struct kvm_irq_ack_notifier *kian)
{
mutex_lock(&kvm->irq_lock);
- hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
+ hlist_add_head_rcu(&kian->link, &kvm->irq_ack_notifier_list);
mutex_unlock(&kvm->irq_lock);
}
@@ -195,8 +204,9 @@ void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
struct kvm_irq_ack_notifier *kian)
{
mutex_lock(&kvm->irq_lock);
- hlist_del_init(&kian->link);
+ hlist_del_init_rcu(&kian->link);
mutex_unlock(&kvm->irq_lock);
+ synchronize_rcu();
}
int kvm_request_irq_source_id(struct kvm *kvm)
@@ -205,16 +215,17 @@ int kvm_request_irq_source_id(struct kvm *kvm)
int irq_source_id;
mutex_lock(&kvm->irq_lock);
- irq_source_id = find_first_zero_bit(bitmap,
- sizeof(kvm->arch.irq_sources_bitmap));
+ irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
- if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
+ if (irq_source_id >= BITS_PER_LONG) {
printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
- return -EFAULT;
+ irq_source_id = -EFAULT;
+ goto unlock;
}
ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
set_bit(irq_source_id, bitmap);
+unlock:
mutex_unlock(&kvm->irq_lock);
return irq_source_id;
@@ -228,13 +239,23 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
mutex_lock(&kvm->irq_lock);
if (irq_source_id < 0 ||
- irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
+ irq_source_id >= BITS_PER_LONG) {
printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
- return;
+ goto unlock;
}
- for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
- clear_bit(irq_source_id, &kvm->arch.irq_states[i]);
clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
+ if (!irqchip_in_kernel(kvm))
+ goto unlock;
+
+ for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++) {
+ clear_bit(irq_source_id, &kvm->arch.vioapic->irq_states[i]);
+ if (i >= 16)
+ continue;
+#ifdef CONFIG_X86
+ clear_bit(irq_source_id, &pic_irqchip(kvm)->irq_states[i]);
+#endif
+ }
+unlock:
mutex_unlock(&kvm->irq_lock);
}
@@ -243,7 +264,7 @@ void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
{
mutex_lock(&kvm->irq_lock);
kimn->irq = irq;
- hlist_add_head(&kimn->link, &kvm->mask_notifier_list);
+ hlist_add_head_rcu(&kimn->link, &kvm->mask_notifier_list);
mutex_unlock(&kvm->irq_lock);
}
@@ -251,8 +272,9 @@ void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
struct kvm_irq_mask_notifier *kimn)
{
mutex_lock(&kvm->irq_lock);
- hlist_del(&kimn->link);
+ hlist_del_rcu(&kimn->link);
mutex_unlock(&kvm->irq_lock);
+ synchronize_rcu();
}
void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
@@ -260,33 +282,37 @@ void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
struct kvm_irq_mask_notifier *kimn;
struct hlist_node *n;
- WARN_ON(!mutex_is_locked(&kvm->irq_lock));
-
- hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(kimn, n, &kvm->mask_notifier_list, link)
if (kimn->irq == irq)
kimn->func(kimn, mask);
-}
-
-static void __kvm_free_irq_routing(struct list_head *irq_routing)
-{
- struct kvm_kernel_irq_routing_entry *e, *n;
-
- list_for_each_entry_safe(e, n, irq_routing, link)
- kfree(e);
+ rcu_read_unlock();
}
void kvm_free_irq_routing(struct kvm *kvm)
{
- mutex_lock(&kvm->irq_lock);
- __kvm_free_irq_routing(&kvm->irq_routing);
- mutex_unlock(&kvm->irq_lock);
+ /* Called only during vm destruction. Nobody can use the pointer
+ at this stage */
+ kfree(kvm->irq_routing);
}
-static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
+static int setup_routing_entry(struct kvm_irq_routing_table *rt,
+ struct kvm_kernel_irq_routing_entry *e,
const struct kvm_irq_routing_entry *ue)
{
int r = -EINVAL;
int delta;
+ struct kvm_kernel_irq_routing_entry *ei;
+ struct hlist_node *n;
+
+ /*
+ * Do not allow GSI to be mapped to the same irqchip more than once.
+ * Allow only one to one mapping between GSI and MSI.
+ */
+ hlist_for_each_entry(ei, n, &rt->map[ue->gsi], link)
+ if (ei->type == KVM_IRQ_ROUTING_MSI ||
+ ue->u.irqchip.irqchip == ei->irqchip.irqchip)
+ return r;
e->gsi = ue->gsi;
e->type = ue->type;
@@ -309,6 +335,9 @@ static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
}
e->irqchip.irqchip = ue->u.irqchip.irqchip;
e->irqchip.pin = ue->u.irqchip.pin + delta;
+ if (e->irqchip.pin >= KVM_IOAPIC_NUM_PINS)
+ goto out;
+ rt->chip[ue->u.irqchip.irqchip][e->irqchip.pin] = ue->gsi;
break;
case KVM_IRQ_ROUTING_MSI:
e->set = kvm_set_msi;
@@ -319,6 +348,8 @@ static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
default:
goto out;
}
+
+ hlist_add_head(&e->link, &rt->map[e->gsi]);
r = 0;
out:
return r;
@@ -330,43 +361,53 @@ int kvm_set_irq_routing(struct kvm *kvm,
unsigned nr,
unsigned flags)
{
- struct list_head irq_list = LIST_HEAD_INIT(irq_list);
- struct list_head tmp = LIST_HEAD_INIT(tmp);
- struct kvm_kernel_irq_routing_entry *e = NULL;
- unsigned i;
+ struct kvm_irq_routing_table *new, *old;
+ u32 i, j, nr_rt_entries = 0;
int r;
for (i = 0; i < nr; ++i) {
+ if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
+ return -EINVAL;
+ nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
+ }
+
+ nr_rt_entries += 1;
+
+ new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head))
+ + (nr * sizeof(struct kvm_kernel_irq_routing_entry)),
+ GFP_KERNEL);
+
+ if (!new)
+ return -ENOMEM;
+
+ new->rt_entries = (void *)&new->map[nr_rt_entries];
+
+ new->nr_rt_entries = nr_rt_entries;
+ for (i = 0; i < 3; i++)
+ for (j = 0; j < KVM_IOAPIC_NUM_PINS; j++)
+ new->chip[i][j] = -1;
+
+ for (i = 0; i < nr; ++i) {
r = -EINVAL;
- if (ue->gsi >= KVM_MAX_IRQ_ROUTES)
- goto out;
if (ue->flags)
goto out;
- r = -ENOMEM;
- e = kzalloc(sizeof(*e), GFP_KERNEL);
- if (!e)
- goto out;
- r = setup_routing_entry(e, ue);
+ r = setup_routing_entry(new, &new->rt_entries[i], ue);
if (r)
goto out;
++ue;
- list_add(&e->link, &irq_list);
- e = NULL;
}
mutex_lock(&kvm->irq_lock);
- list_splice(&kvm->irq_routing, &tmp);
- INIT_LIST_HEAD(&kvm->irq_routing);
- list_splice(&irq_list, &kvm->irq_routing);
- INIT_LIST_HEAD(&irq_list);
- list_splice(&tmp, &irq_list);
+ old = kvm->irq_routing;
+ rcu_assign_pointer(kvm->irq_routing, new);
mutex_unlock(&kvm->irq_lock);
+ synchronize_rcu();
+ new = old;
r = 0;
out:
- kfree(e);
- __kvm_free_irq_routing(&irq_list);
+ kfree(new);
return r;
}