An iofd allows an eventfd to attach to a specific PIO/MMIO region in the
guest. Any guest-writes to that region will trigger an eventfd signal.
Signed-off-by: Gregory Haskins <ghaskins@xxxxxxxxxx>
---
kvm/libkvm/libkvm.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++++
kvm/libkvm/libkvm.h | 31 ++++++++++++++++++++++++++++++
2 files changed, 83 insertions(+), 0 deletions(-)
diff --git a/kvm/libkvm/libkvm.c b/kvm/libkvm/libkvm.c
index 74a21a2..0139abd 100644
--- a/kvm/libkvm/libkvm.c
+++ b/kvm/libkvm/libkvm.c
@@ -1497,6 +1497,45 @@ int kvm_destroy_irqfd(kvm_context_t kvm, int fd, int flags)
return r;
}
+int kvm_assign_iofd(kvm_context_t kvm, unsigned long addr, size_t len,
+ int fd, int type, int flags)
+{
+ int r;
+ struct kvm_iofd data = {
+ .addr = addr,
+ .len = len,
+ .fd = fd,
+ .flags = type ? KVM_IOFD_FLAG_PIO : 0,
+ };
+
+ if (!kvm_check_extension(kvm, KVM_CAP_EVENTFD))
+ return -ENOENT;
+
+ r = ioctl(kvm->vm_fd, KVM_IOFD, &data);
+ if (r == -1)
+ r = -errno;
+ return r;
+}
+
+int kvm_deassign_iofd(kvm_context_t kvm, unsigned long addr, size_t len,
+ int type, int flags)
+{
+ int r;
+ struct kvm_iofd data = {
+ .addr = addr,
+ .len = len,
+ .flags = KVM_IOFD_FLAG_DEASSIGN | (type ? KVM_IOFD_FLAG_PIO : 0),
+ };
+
+ if (!kvm_check_extension(kvm, KVM_CAP_EVENTFD))
+ return -ENOENT;
+
+ r = ioctl(kvm->vm_fd, KVM_IOFD, &data);
+ if (r == -1)
+ r = -errno;
+ return r;
+}
+
#else /* KVM_CAP_EVENTFD */
int kvm_create_irqfd(kvm_context_t kvm, int gsi, int flags)
@@ -1509,4 +1548,17 @@ int kvm_destroy_irqfd(kvm_context_t kvm, int fd, int flags)
return -ENOENT;
}
+int kvm_assign_iofd(kvm_context_t kvm, unsigned long addr, size_t len,
+ int fd, int type, int flags)
+{
+ return -ENOENT;
+}
+
+int kvm_deassign_iofd(kvm_context_t kvm, unsigned long addr, size_t len,
+ int type, int flags)
+{
+ return -ENOENT;
+}
+
#endif /* KVM_CAP_EVENTFD */
+
diff --git a/kvm/libkvm/libkvm.h b/kvm/libkvm/libkvm.h
index 322b4cd..89c558a 100644
--- a/kvm/libkvm/libkvm.h
+++ b/kvm/libkvm/libkvm.h
@@ -881,6 +881,37 @@ int kvm_create_irqfd(kvm_context_t kvm, int gsi, int flags);
*/
int kvm_destroy_irqfd(kvm_context_t kvm, int fd, int flags);
+/*!
+ * \brief Assign an eventfd to an IO port (PIO or MMIO)
+ *
+ * Assigns an eventfd based file-descriptor to a specific PIO or MMIO
+ * address range. Any guest writes to the specified range will generate
+ * an eventfd signal.
+ *
+ * \param kvm Pointer to the current kvm_context
+ * \param addr The IO address
+ * \param len The length of the IO region at the address
+ * \param fd The eventfd file-descriptor
+ * \param type MMIO=0, PIO=1
+ * \param flags reserved, must be zero
+ */
+int kvm_assign_iofd(kvm_context_t kvm, unsigned long addr, size_t len,
+ int fd, int type, int flags);
+
+/*!
+ * \brief Deassign an iofd from a previously registered IO port
+ *
+ * Deassigns an iofd previously registered with kvm_assign_iofd()
+ *
+ * \param kvm Pointer to the current kvm_context
+ * \param addr The IO address
+ * \param len The length of the IO region at the address
+ * \param type MMIO=0, PIO=1
+ * \param flags reserved, must be zero
+ */
+int kvm_deassign_iofd(kvm_context_t kvm, unsigned long addr, size_t len,
+ int type, int flags);
+
#ifdef KVM_CAP_DEVICE_MSIX
int kvm_assign_set_msix_nr(kvm_context_t kvm,
struct kvm_assigned_msix_nr *msix_nr);
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
