From 8a39d00670f0792c1186e442e1dd28fe0326f2ee Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Fri, 15 Jul 2016 12:43:26 +0100 Subject: [PATCH] KVM: kvm_io_bus: Add kvm_io_bus_get_dev() call The kvm_io_bus framework is a nice place of holding information about various MMIO regions for kernel emulated devices. Add a call to retrieve the kvm_io_device structure which is associated with a certain MMIO address. This avoids to duplicate kvm_io_bus' knowledge of MMIO regions without having to fake MMIO calls if a user needs the device a certain MMIO address belongs to. This will be used by the ITS emulation to get the associated ITS device when someone triggers an MSI via an ioctl from userspace. Signed-off-by: Andre Przywara Reviewed-by: Eric Auger Reviewed-by: Marc Zyngier Acked-by: Christoffer Dall Acked-by: Paolo Bonzini Tested-by: Eric Auger Signed-off-by: Marc Zyngier --- include/linux/kvm_host.h | 2 ++ virt/kvm/kvm_main.c | 24 ++++++++++++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 0640ee92b978..614a98137c5f 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -164,6 +164,8 @@ int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, int len, struct kvm_io_device *dev); int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, struct kvm_io_device *dev); +struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, + gpa_t addr); #ifdef CONFIG_KVM_ASYNC_PF struct kvm_async_pf { diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ef54b4c31792..bd2eb92c5d0e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3496,6 +3496,30 @@ int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, return r; } +struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx, + gpa_t addr) +{ + struct kvm_io_bus *bus; + int dev_idx, srcu_idx; + struct kvm_io_device *iodev = NULL; + + srcu_idx = srcu_read_lock(&kvm->srcu); + + bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu); + + dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1); + if (dev_idx < 0) + goto out_unlock; + + iodev = bus->range[dev_idx].dev; + +out_unlock: + srcu_read_unlock(&kvm->srcu, srcu_idx); + + return iodev; +} +EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev); + static struct notifier_block kvm_cpu_notifier = { .notifier_call = kvm_cpu_hotplug, }; -- GitLab