fix: KVM: x86: Unexport kvm_x86_ops (v5.18)

[lttng-modules.git] / include / wrapper / kvm-x86.h

diff --git a/include/wrapper/kvm-x86.h b/include/wrapper/kvm-x86.h
new file mode 100644 (file)
index 0000000..2007aeb
--- /dev/null
+++ b/include/wrapper/kvm-x86.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
+ *
+ * wrapper/kvm-x86.h
+ *
+ * Copyright (C) 2022 Michael Jeanson <mjeanson@efficios.com>
+ */
+
+#ifndef _LTTNG_WRAPPER_KVM_X86_H
+#define _LTTNG_WRAPPER_KVM_X86_H
+
+#include <linux/kvm_host.h>
+#include <lttng/kernel-version.h>
+
+#if LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,18,0)
+
+#ifdef CONFIG_KALLSYMS_ALL
+#include <linux/kallsyms.h>
+#include <wrapper/kallsyms.h>
+
+static struct kvm_x86_ops *kvm_x86_ops_sym;
+
+static inline
+void lttng_kvm_x86_get_exit_info(
+               struct kvm_vcpu *vcpu, u32 *reason,
+               u64 *info1, u64 *info2,
+               u32 *exit_int_info, u32 *exit_int_info_err_code)
+{
+       if (!kvm_x86_ops_sym)
+               kvm_x86_ops_sym =
+                       (void *) kallsyms_lookup_dataptr("kvm_x86_ops");
+
+       if (kvm_x86_ops_sym) {
+               kvm_x86_ops_sym->get_exit_info(vcpu, reason, info1, info2,
+                               exit_int_info, exit_int_info_err_code);
+       } else {
+               printk_once(KERN_WARNING "LTTng: kvm_x86_ops symbol lookup failed.\n");
+       }
+}
+
+static inline
+u64 lttng_kvm_x86_get_segment_base(struct kvm_vcpu *vcpu, int seg)
+{
+       if (!kvm_x86_ops_sym)
+               kvm_x86_ops_sym =
+                       (void *) kallsyms_lookup_dataptr("kvm_x86_ops");
+
+       if (kvm_x86_ops_sym) {
+               return kvm_x86_ops_sym->get_segment_base(vcpu, seg);
+       } else {
+               printk_once(KERN_WARNING "LTTng: kvm_x86_ops symbol lookup failed.\n");
+               return 0;
+       }
+}
+
+/*
+ * Canary function to check for 'kvm_x86_ops' at compile time.
+ *
+ * From 'arch/x86/include/asm/kvm_host.h':
+ *
+ *   extern struct kvm_x86_ops kvm_x86_ops;;
+ */
+static inline
+unsigned int __canary__kvm_x86_ops(void)
+{
+       return kvm_x86_ops.vm_size;
+}
+
+#endif /* CONFIG_KALLSYMS_ALL */
+
+#endif
+
+#endif /* _LTTNG_WRAPPER_KVM_X86_H */