Save/Restore Support: Implement code for arch suspend/resume

Before suspending the domain the shared_info_page is unmapped and for PVs the
pagetables should be canonicalized. After resume the shared_info_page should be
mapped again.

Signed-off-by: Bruno Alvisio <bruno.alvisio@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

diff --git a/arch/x86/setup.c b/arch/x86/setup.c
index 60e12c0c5d92d1d2864c9d93f1a28fbbbd80849c..4fd8e39c6d7334726c24591e79078f402bddcff2 100644 (file)
--- a/arch/x86/setup.c
+++ b/arch/x86/setup.c
@@ -32,6 +32,7 @@
 #include <xen/xen.h>
 #include <xen/arch-x86/cpuid.h>
 #include <xen/arch-x86/hvm/start_info.h>
+#include <xen/hvm/params.h>
 
 #ifdef CONFIG_PARAVIRT
 /*
@@ -41,6 +42,11 @@
 union start_info_union start_info_union;
 #endif
 
+/*
+ * This pointer holds a reference to the copy of the start_info struct.
+ */
+static start_info_t *start_info_ptr;
+
 /*
  * Shared page for communicating with the hypervisor.
  * Events flags go here, for example.
@@ -213,18 +219,63 @@ arch_init(void *par)
 #ifdef CONFIG_PARAVIRT
        memcpy(&start_info, par, sizeof(start_info));
 #endif
+       start_info_ptr = (start_info_t *)par;
 
        start_kernel((start_info_t *)par);
 }
 
 void arch_pre_suspend(void)
 {
+#ifdef CONFIG_PARAVIRT
+   /* Replace xenstore and console mfns with the correspondent pfns */
+    start_info_ptr->store_mfn =
+        virt_to_pfn(mfn_to_virt(start_info_ptr->store_mfn));
+    start_info_ptr->console.domU.mfn =
+        virt_to_pfn(mfn_to_virt(start_info_ptr->console.domU.mfn));
+#else
+    uint64_t store_v;
+    uint64_t console_v;
+
+    if( hvm_get_parameter(HVM_PARAM_STORE_PFN, &store_v) )
+        BUG();
+    start_info_ptr->store_mfn = store_v;
+
+    if( hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &console_v) )
+        BUG();
+    start_info_ptr->console.domU.mfn = console_v;
+#endif
+    unmap_shared_info();
 
+    arch_mm_pre_suspend();
 }
 
 void arch_post_suspend(int canceled)
 {
+#if CONFIG_PARAVIRT
+    if (canceled) {
+        start_info_ptr->store_mfn = pfn_to_mfn(start_info_ptr->store_mfn);
+        start_info_ptr->console.domU.mfn = pfn_to_mfn(start_info_ptr->console.domU.mfn);
+    } else {
+        memcpy(&start_info, start_info_ptr, sizeof(start_info_t));
+    }
+#else
+    uint64_t store_v;
+    uint64_t console_v;
+
+    if (hvm_get_parameter(HVM_PARAM_STORE_PFN, &store_v))
+        BUG();
+    start_info_ptr->store_mfn = pfn_to_mfn(store_v);
 
+    if (hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &console_v))
+        BUG();
+    start_info_ptr->console.domU.mfn = pfn_to_mfn(console_v);
+#endif
+
+    HYPERVISOR_shared_info = map_shared_info((void*) start_info_ptr);
+#ifndef CONFIG_PARAVIRT
+    xen_callback_vector();
+#endif
+    arch_mm_post_suspend(canceled);
 }
 
 void