Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 57 insertions, 0 deletions

diff --git a/linux-user/i386/target_cpu.h b/linux-user/i386/target_cpu.h
new file mode 100644
index 000000000..52caf788c
--- /dev/null
+++ b/linux-user/i386/target_cpu.h
@@ -0,0 +1,57 @@
+/*
+ * i386 specific CPU ABI and functions for linux-user
+ *
+ *  Copyright (c) 2003 Fabrice Bellard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef I386_TARGET_CPU_H
+#define I386_TARGET_CPU_H
+
+static inline void cpu_clone_regs_child(CPUX86State *env, target_ulong newsp,
+                                        unsigned flags)
+{
+    if (newsp) {
+        env->regs[R_ESP] = newsp;
+    }
+    env->regs[R_EAX] = 0;
+}
+
+static inline void cpu_clone_regs_parent(CPUX86State *env, unsigned flags)
+{
+}
+
+abi_long do_arch_prctl(CPUX86State *env, int code, abi_ulong addr);
+
+#if defined(TARGET_ABI32)
+abi_long do_set_thread_area(CPUX86State *env, abi_ulong ptr);
+
+static inline void cpu_set_tls(CPUX86State *env, target_ulong newtls)
+{
+    do_set_thread_area(env, newtls);
+    cpu_x86_load_seg(env, R_GS, env->segs[R_GS].selector);
+}
+#else
+static inline void cpu_set_tls(CPUX86State *env, target_ulong newtls)
+{
+    do_arch_prctl(env, TARGET_ARCH_SET_FS, newtls);
+}
+#endif /* defined(TARGET_ABI32) */
+
+static inline abi_ulong get_sp_from_cpustate(CPUX86State *state)
+{
+    return state->regs[R_ESP];
+}
+#endif /* I386_TARGET_CPU_H */