From 9957c86d659a4d5a2bed25ccbd3bfc9c3f25e658 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Mon, 30 Jun 2014 20:51:11 +1000 Subject: KVM: Move all accesses to kvm::irq_routing into irqchip.c Now that struct _irqfd does not keep a reference to storage pointed to by the irq_routing field of struct kvm, we can move the statement that updates it out from under the irqfds.lock and put it in kvm_set_irq_routing() instead. That means we then have to take a srcu_read_lock on kvm->irq_srcu around the irqfd_update call in kvm_irqfd_assign(), since holding the kvm->irqfds.lock no longer ensures that that the routing can't change. Combined with changing kvm_irq_map_gsi() and kvm_irq_map_chip_pin() to take a struct kvm * argument instead of the pointer to the routing table, this allows us to to move all references to kvm->irq_routing into irqchip.c. That in turn allows us to move the definition of the kvm_irq_routing_table struct into irqchip.c as well. Signed-off-by: Paul Mackerras Tested-by: Eric Auger Tested-by: Cornelia Huck Signed-off-by: Paolo Bonzini --- virt/kvm/irqchip.c | 39 +++++++++++++++++++++++++-------------- 1 file changed, 25 insertions(+), 14 deletions(-) (limited to 'virt/kvm/irqchip.c') diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c index f4648dd94888..04faac50cef5 100644 --- a/virt/kvm/irqchip.c +++ b/virt/kvm/irqchip.c @@ -31,12 +31,26 @@ #include #include "irq.h" -int kvm_irq_map_gsi(struct kvm_kernel_irq_routing_entry *entries, - struct kvm_irq_routing_table *irq_rt, int gsi) +struct kvm_irq_routing_table { + int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS]; + struct kvm_kernel_irq_routing_entry *rt_entries; + u32 nr_rt_entries; + /* + * Array indexed by gsi. Each entry contains list of irq chips + * the gsi is connected to. + */ + struct hlist_head map[0]; +}; + +int kvm_irq_map_gsi(struct kvm *kvm, + struct kvm_kernel_irq_routing_entry *entries, int gsi) { + struct kvm_irq_routing_table *irq_rt; struct kvm_kernel_irq_routing_entry *e; int n = 0; + irq_rt = srcu_dereference_check(kvm->irq_routing, &kvm->irq_srcu, + lockdep_is_held(&kvm->irq_lock)); if (gsi < irq_rt->nr_rt_entries) { hlist_for_each_entry(e, &irq_rt->map[gsi], link) { entries[n] = *e; @@ -47,21 +61,21 @@ int kvm_irq_map_gsi(struct kvm_kernel_irq_routing_entry *entries, return n; } -int kvm_irq_map_chip_pin(struct kvm_irq_routing_table *irq_rt, - unsigned irqchip, unsigned pin) +int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin) { + struct kvm_irq_routing_table *irq_rt; + + irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu); return irq_rt->chip[irqchip][pin]; } bool kvm_irq_has_notifier(struct kvm *kvm, unsigned irqchip, unsigned pin) { - struct kvm_irq_routing_table *irq_rt; struct kvm_irq_ack_notifier *kian; int gsi, idx; idx = srcu_read_lock(&kvm->irq_srcu); - irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu); - gsi = kvm_irq_map_chip_pin(irq_rt, irqchip, pin); + gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin); if (gsi != -1) hlist_for_each_entry_rcu(kian, &kvm->irq_ack_notifier_list, link) @@ -78,15 +92,13 @@ EXPORT_SYMBOL_GPL(kvm_irq_has_notifier); void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin) { - struct kvm_irq_routing_table *irq_rt; struct kvm_irq_ack_notifier *kian; int gsi, idx; trace_kvm_ack_irq(irqchip, pin); idx = srcu_read_lock(&kvm->irq_srcu); - irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu); - gsi = kvm_irq_map_chip_pin(irq_rt, irqchip, pin); + gsi = kvm_irq_map_chip_pin(kvm, irqchip, pin); if (gsi != -1) hlist_for_each_entry_rcu(kian, &kvm->irq_ack_notifier_list, link) @@ -143,7 +155,6 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, { struct kvm_kernel_irq_routing_entry irq_set[KVM_NR_IRQCHIPS]; int ret = -1, i, idx; - struct kvm_irq_routing_table *irq_rt; trace_kvm_set_irq(irq, level, irq_source_id); @@ -152,8 +163,7 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, * writes to the unused one. */ idx = srcu_read_lock(&kvm->irq_srcu); - irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu); - i = kvm_irq_map_gsi(irq_set, irq_rt, irq); + i = kvm_irq_map_gsi(kvm, irq_set, irq); srcu_read_unlock(&kvm->irq_srcu, idx); while(i--) { @@ -250,7 +260,8 @@ int kvm_set_irq_routing(struct kvm *kvm, mutex_lock(&kvm->irq_lock); old = kvm->irq_routing; - kvm_irq_routing_update(kvm, new); + rcu_assign_pointer(kvm->irq_routing, new); + kvm_irq_routing_update(kvm); mutex_unlock(&kvm->irq_lock); synchronize_srcu_expedited(&kvm->irq_srcu); -- cgit v1.2.3