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authorEric Auger <eric.auger@linaro.org>2015-09-18 22:29:42 +0800
committerPaolo Bonzini <pbonzini@redhat.com>2015-10-01 15:06:44 +0200
commit166c9775f1f8b8f00ad1db0fa5c8fc74059d965d (patch)
tree06d78f0f45d69b861ecc3be064469bcee19c2b21 /include/linux/kvm_irqfd.h
parent37d9fe4783ffcaddcc4afe67626691e62c5ab30e (diff)
KVM: create kvm_irqfd.h
Move _irqfd_resampler and _irqfd struct declarations in a new public header: kvm_irqfd.h. They are respectively renamed into kvm_kernel_irqfd_resampler and kvm_kernel_irqfd. Those datatypes will be used by architecture specific code, in the context of IRQ bypass manager integration. Signed-off-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'include/linux/kvm_irqfd.h')
-rw-r--r--include/linux/kvm_irqfd.h69
1 files changed, 69 insertions, 0 deletions
diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h
new file mode 100644
index 000000000000..f926b39a26b6
--- /dev/null
+++ b/include/linux/kvm_irqfd.h
@@ -0,0 +1,69 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * irqfd: Allows an fd to be used to inject an interrupt to the guest
+ * Credit goes to Avi Kivity for the original idea.
+ */
+
+#ifndef __LINUX_KVM_IRQFD_H
+#define __LINUX_KVM_IRQFD_H
+
+#include <linux/kvm_host.h>
+#include <linux/poll.h>
+
+/*
+ * Resampling irqfds are a special variety of irqfds used to emulate
+ * level triggered interrupts. The interrupt is asserted on eventfd
+ * trigger. On acknowledgment through the irq ack notifier, the
+ * interrupt is de-asserted and userspace is notified through the
+ * resamplefd. All resamplers on the same gsi are de-asserted
+ * together, so we don't need to track the state of each individual
+ * user. We can also therefore share the same irq source ID.
+ */
+struct kvm_kernel_irqfd_resampler {
+ struct kvm *kvm;
+ /*
+ * List of resampling struct _irqfd objects sharing this gsi.
+ * RCU list modified under kvm->irqfds.resampler_lock
+ */
+ struct list_head list;
+ struct kvm_irq_ack_notifier notifier;
+ /*
+ * Entry in list of kvm->irqfd.resampler_list. Use for sharing
+ * resamplers among irqfds on the same gsi.
+ * Accessed and modified under kvm->irqfds.resampler_lock
+ */
+ struct list_head link;
+};
+
+struct kvm_kernel_irqfd {
+ /* Used for MSI fast-path */
+ struct kvm *kvm;
+ wait_queue_t wait;
+ /* Update side is protected by irqfds.lock */
+ struct kvm_kernel_irq_routing_entry irq_entry;
+ seqcount_t irq_entry_sc;
+ /* Used for level IRQ fast-path */
+ int gsi;
+ struct work_struct inject;
+ /* The resampler used by this irqfd (resampler-only) */
+ struct kvm_kernel_irqfd_resampler *resampler;
+ /* Eventfd notified on resample (resampler-only) */
+ struct eventfd_ctx *resamplefd;
+ /* Entry in list of irqfds for a resampler (resampler-only) */
+ struct list_head resampler_link;
+ /* Used for setup/shutdown */
+ struct eventfd_ctx *eventfd;
+ struct list_head list;
+ poll_table pt;
+ struct work_struct shutdown;
+};
+
+#endif /* __LINUX_KVM_IRQFD_H */