From: Peter Dinda <pdinda@northwestern.edu>
Date: Fri, 13 Apr 2012 21:41:08 +0000 (-0500)
Subject: Linux host hypercall interface implementation
X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=commitdiff_plain;h=ad56fb16a79581bf088c8e5a9143d88e8c2f0055;p=palacios.git

Linux host hypercall interface implementation
---

diff --git a/linux_module/iface-host-hypercall.c b/linux_module/iface-host-hypercall.c
new file mode 100644
index 0000000..f5682db
--- /dev/null
+++ b/linux_module/iface-host-hypercall.c
@@ -0,0 +1,150 @@
+/* 
+ * Linux interface for guest-context code injection
+ *
+ * (c) Kyle C. Hale 2011
+ *
+ */
+
+#include <linux/elf.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+
+#include <linux/module.h>
+
+#include <interfaces/vmm_host_hypercall.h>
+
+#include "palacios.h"
+#include "vm.h"
+#include "linux-exts.h"
+#include "iface-host-hypercall.h"
+
+static int host_hypercall_nop(palacios_core_t core,
+			      unsigned int hcall_id, 
+			      struct guest_accessors *acc,
+			      void *priv_data) {
+  printk("palacios: host_hypercall_nop dummy handler invoked\n");
+  printk(" rip=%p\n rsp=%p\n rbp=%p\n rflags=%p\n",
+	 (void*)(acc->get_rip(core)),
+	 (void*)(acc->get_rsp(core)),
+	 (void*)(acc->get_rbp(core)),
+	 (void*)(acc->get_rflags(core)));
+
+  printk(" rax=%p\n rbx=%p\n rcx=%p\n rdx=%p\n rsi=%p\n rdi=%p\n",
+	 (void*)(acc->get_rax(core)),
+	 (void*)(acc->get_rbx(core)),
+	 (void*)(acc->get_rcx(core)),
+	 (void*)(acc->get_rdx(core)),
+	 (void*)(acc->get_rsi(core)),
+	 (void*)(acc->get_rdi(core)));
+  printk(" r8=%p\n r9=%p\n r10=%p\n r11=%p\n r12=%p\n r13=%p\n r14=%p\n r15=%p\n",
+	 (void*)(acc->get_r8(core)),
+	 (void*)(acc->get_r9(core)),
+	 (void*)(acc->get_r10(core)),
+	 (void*)(acc->get_r11(core)),
+	 (void*)(acc->get_r12(core)),
+	 (void*)(acc->get_r13(core)),
+	 (void*)(acc->get_r14(core)),
+	 (void*)(acc->get_r15(core)));
+  printk(" cr0=%p\n cr2=%p\n cr3=%p\n cr4=%p\n cr8=%p\n efer=%p\n",
+	 (void*)(acc->get_cr0(core)),
+	 (void*)(acc->get_cr2(core)),
+	 (void*)(acc->get_cr3(core)),
+	 (void*)(acc->get_cr4(core)),
+	 (void*)(acc->get_cr8(core)),
+	 (void*)(acc->get_efer(core)));
+  return 0;
+}
+
+
+static int vm_hypercall_add (struct v3_guest *guest, 
+			     unsigned int cmd, 
+			     unsigned long arg, 
+			     void *priv_data) {
+
+  struct hcall_data hdata;
+  void *func;
+
+  if (copy_from_user(&hdata,(void __user *) arg, sizeof(struct hcall_data))) { 
+    printk("palacios: copy from user in getting input for hypercall add\n");
+    return -EFAULT;
+  }
+
+  if (0==strcmp(hdata.fn,"")) { 
+    printk("palacios: no hypercall function supplied, using default\n");
+    func = (void*) host_hypercall_nop;
+  } else {
+    func = __symbol_get(hdata.fn);
+  }
+
+  if (func == NULL) { 
+    printk("palacios: cannot find function '%s' for hypercall addition - perhaps your module hasn't been loaded yet?\n",hdata.fn);
+    return -EFAULT;
+  }
+
+  if (v3_register_host_hypercall(guest->v3_ctx, 
+				 hdata.hcall_nr,
+				 func,
+				 NULL)) { 
+    printk("palacios: cannot register hypercall 0x%x for function %s (%p)\n",
+	   hdata.hcall_nr, hdata.fn, func);
+    return -EFAULT;
+  } 
+
+  printk("palacios: hypercall %d (0x%x) registered for function %s (%p)\n", 
+	 hdata.hcall_nr,hdata.hcall_nr,hdata.fn,func);
+  return 0;
+}
+
+static int vm_hypercall_remove (struct v3_guest *guest, 
+				unsigned int cmd, 
+				unsigned long arg, 
+				void *priv_data) {
+
+  struct hcall_data hdata;
+
+  if (copy_from_user(&hdata,(void __user *) arg, sizeof(struct hcall_data))) { 
+    printk("palacios: copy from user in getting input for hypercall remove\n");
+    return -EFAULT;
+  }
+  if (v3_unregister_host_hypercall(guest->v3_ctx, 
+				   hdata.hcall_nr)) {
+    printk("palacios: cannot unregister hypercall 0x%x\n", hdata.hcall_nr);
+    return -EFAULT;
+  } 
+
+  printk("palacios: hypercall %d (0x%x) unregistered\n", 
+	 hdata.hcall_nr,hdata.hcall_nr);
+
+  return 0;
+}
+
+static int init_host_hypercall (void) {
+    return 0;
+}
+
+
+static int deinit_host_hypercall (void) {
+    return 0;
+}
+
+static int guest_init_host_hypercall (struct v3_guest * guest, void ** vm_data) {
+    add_guest_ctrl(guest, V3_VM_HYPERCALL_ADD, vm_hypercall_add, NULL);
+    add_guest_ctrl(guest, V3_VM_HYPERCALL_REMOVE, vm_hypercall_remove, NULL);
+    return 0;
+}
+
+
+static int guest_deinit_host_hypercall (struct v3_guest * guest, void * vm_data) {
+    return 0;
+}
+
+
+static struct linux_ext host_hypercall_ext = {
+    .name = "HOST_HYPERCALL",
+    .init = init_host_hypercall,
+    .deinit = deinit_host_hypercall,
+    .guest_init = guest_init_host_hypercall,
+    .guest_deinit = guest_deinit_host_hypercall 
+};
+
+register_extension(&host_hypercall_ext);
diff --git a/linux_module/iface-host-hypercall.h b/linux_module/iface-host-hypercall.h
new file mode 100644
index 0000000..8b0f91c
--- /dev/null
+++ b/linux_module/iface-host-hypercall.h
@@ -0,0 +1,15 @@
+#ifndef __IFACE_HOST_HYPERCALL_H__
+#define __IFACE_HOST_HYPERCALL_H__
+
+#define V3_VM_HYPERCALL_ADD 12124
+#define V3_VM_HYPERCALL_REMOVE 12125
+
+
+#define HCALL_NAME_MAX 256
+
+struct hcall_data {
+  int   hcall_nr;
+  char  fn[HCALL_NAME_MAX];
+};
+
+#endif