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, 71 insertions, 0 deletions

diff --git a/bsd-user/i386/target_arch_cpu.c b/bsd-user/i386/target_arch_cpu.c
new file mode 100644
index 000000000..d349e4529
--- /dev/null
+++ b/bsd-user/i386/target_arch_cpu.c
@@ -0,0 +1,71 @@
+/*
+ *  i386 cpu related code
+ *
+ * Copyright (c) 2013 Stacey Son <sson@FreeBSD.org>
+ *
+ *  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, or
+ *  (at your option) any later version.
+ *
+ *  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.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <sys/types.h>
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "qemu.h"
+#include "qemu/timer.h"
+
+#include "target_arch.h"
+
+static uint64_t *idt_table;
+
+uint64_t cpu_get_tsc(CPUX86State *env)
+{
+    return cpu_get_host_ticks();
+}
+
+void bsd_i386_write_dt(void *ptr, unsigned long addr, unsigned long limit,
+                     int flags)
+{
+    unsigned int e1, e2;
+    uint32_t *p;
+    e1 = (addr << 16) | (limit & 0xffff);
+    e2 = ((addr >> 16) & 0xff) | (addr & 0xff000000) | (limit & 0x000f0000);
+    e2 |= flags;
+    p = ptr;
+    p[0] = tswap32(e1);
+    p[1] = tswap32(e2);
+}
+
+
+static void set_gate(void *ptr, unsigned int type, unsigned int dpl,
+                     uint32_t addr, unsigned int sel)
+{
+    uint32_t *p, e1, e2;
+    e1 = (addr & 0xffff) | (sel << 16);
+    e2 = (addr & 0xffff0000) | 0x8000 | (dpl << 13) | (type << 8);
+    p = ptr;
+    p[0] = tswap32(e1);
+    p[1] = tswap32(e2);
+}
+
+/* only dpl matters as we do only user space emulation */
+void bsd_i386_set_idt(int n, unsigned int dpl)
+{
+    set_gate(idt_table + n, 0, dpl, 0, 0);
+}
+
+void bsd_i386_set_idt_base(uint64_t base)
+{
+    idt_table = g2h_untagged(base);
+}
+