xen: move VCPUOP_register_vcpu_info to common code

Move the implementation of VCPUOP_register_vcpu_info from x86 specific
to commmon code.

Move vcpu_info_mfn from an arch specific vcpu sub-field to the common
vcpu struct.
Move the initialization of vcpu_info_mfn to common code.

Move unmap_vcpu_info and the call to unmap_vcpu_info at domain
destruction time to common code.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>

xen/arch/x86/domain.c

@@ -385,8 +385,6 @@ int vcpu_initialise(struct vcpu *v)
 
     vmce_init_vcpu(v);
 
-    v->arch.vcpu_info_mfn = INVALID_MFN;
-
     if ( is_hvm_domain(d) )
     {
         rc = hvm_vcpu_initialise(v);
@@ -960,99 +958,6 @@ int arch_vcpu_reset(struct vcpu *v)
     return 0;
 }
 
-/* 
- * Unmap the vcpu info page if the guest decided to place it somewhere
- * else.  This is only used from arch_domain_destroy, so there's no
- * need to do anything clever.
- */
-static void
-unmap_vcpu_info(struct vcpu *v)
-{
-    unsigned long mfn;
-
-    if ( v->arch.vcpu_info_mfn == INVALID_MFN )
-        return;
-
-    mfn = v->arch.vcpu_info_mfn;
-    unmap_domain_page_global(v->vcpu_info);
-
-    v->vcpu_info = &dummy_vcpu_info;
-    v->arch.vcpu_info_mfn = INVALID_MFN;
-
-    put_page_and_type(mfn_to_page(mfn));
-}
-
-/* 
- * Map a guest page in and point the vcpu_info pointer at it.  This
- * makes sure that the vcpu_info is always pointing at a valid piece
- * of memory, and it sets a pending event to make sure that a pending
- * event doesn't get missed.
- */
-static int
-map_vcpu_info(struct vcpu *v, unsigned long gfn, unsigned offset)
-{
-    struct domain *d = v->domain;
-    void *mapping;
-    vcpu_info_t *new_info;
-    struct page_info *page;
-    int i;
-
-    if ( offset > (PAGE_SIZE - sizeof(vcpu_info_t)) )
-        return -EINVAL;
-
-    if ( v->arch.vcpu_info_mfn != INVALID_MFN )
-        return -EINVAL;
-
-    /* Run this command on yourself or on other offline VCPUS. */
-    if ( (v != current) && !test_bit(_VPF_down, &v->pause_flags) )
-        return -EINVAL;
-
-    page = get_page_from_gfn(d, gfn, NULL, P2M_ALLOC);
-    if ( !page )
-        return -EINVAL;
-
-    if ( !get_page_type(page, PGT_writable_page) )
-    {
-        put_page(page);
-        return -EINVAL;
-    }
-
-    mapping = __map_domain_page_global(page);
-    if ( mapping == NULL )
-    {
-        put_page_and_type(page);
-        return -ENOMEM;
-    }
-
-    new_info = (vcpu_info_t *)(mapping + offset);
-
-    if ( v->vcpu_info == &dummy_vcpu_info )
-    {
-        memset(new_info, 0, sizeof(*new_info));
-        __vcpu_info(v, new_info, evtchn_upcall_mask) = 1;
-    }
-    else
-    {
-        memcpy(new_info, v->vcpu_info, sizeof(*new_info));
-    }
-
-    v->vcpu_info = new_info;
-    v->arch.vcpu_info_mfn = page_to_mfn(page);
-
-    /* Set new vcpu_info pointer /before/ setting pending flags. */
-    wmb();
-
-    /*
-     * Mark everything as being pending just to make sure nothing gets
-     * lost.  The domain will get a spurious event, but it can cope.
-     */
-    vcpu_info(v, evtchn_upcall_pending) = 1;
-    for ( i = 0; i < BITS_PER_EVTCHN_WORD(d); i++ )
-        set_bit(i, &vcpu_info(v, evtchn_pending_sel));
-
-    return 0;
-}
-
 long
 arch_do_vcpu_op(
     int cmd, struct vcpu *v, XEN_GUEST_HANDLE_PARAM(void) arg)
@@ -1089,22 +994,6 @@ arch_do_vcpu_op(
         break;
     }
 
-    case VCPUOP_register_vcpu_info:
-    {
-        struct domain *d = v->domain;
-        struct vcpu_register_vcpu_info info;
-
-        rc = -EFAULT;
-        if ( copy_from_guest(&info, arg, 1) )
-            break;
-
-        domain_lock(d);
-        rc = map_vcpu_info(v, info.mfn, info.offset);
-        domain_unlock(d);
-
-        break;
-    }
-
     /*
      * XXX Disable for 4.0.0: __update_vcpu_system_time() writes to the given
      * virtual address even when running in another domain's address space.
@@ -1971,8 +1860,6 @@ int domain_relinquish_resources(struct domain *d)
             ret = vcpu_destroy_pagetables(v);
             if ( ret )
                 return ret;
-
-            unmap_vcpu_info(v);
         }
 
         if ( !is_hvm_domain(d) )

xen/common/domain.c

@@ -33,6 +33,7 @@
 #include <xen/xenoprof.h>
 #include <xen/irq.h>
 #include <asm/debugger.h>
+#include <asm/p2m.h>
 #include <asm/processor.h>
 #include <public/sched.h>
 #include <public/sysctl.h>
@@ -142,6 +143,7 @@ struct vcpu *alloc_vcpu(
         v->vcpu_info = ((vcpu_id < XEN_LEGACY_MAX_VCPUS)
                         ? (vcpu_info_t *)&shared_info(d, vcpu_info[vcpu_id])
                         : &dummy_vcpu_info);
+        v->vcpu_info_mfn = INVALID_MFN;
         init_waitqueue_vcpu(v);
     }
 
@@ -513,6 +515,7 @@ int rcu_lock_live_remote_domain_by_id(domid_t dom, struct domain **d)
 int domain_kill(struct domain *d)
 {
     int rc = 0;
+    struct vcpu *v;
 
     if ( d == current->domain )
         return -EINVAL;
@@ -537,6 +540,8 @@ int domain_kill(struct domain *d)
             BUG_ON(rc != -EAGAIN);
             break;
         }
+        for_each_vcpu ( d, v )
+            unmap_vcpu_info(v);
         d->is_dying = DOMDYING_dead;
         /* Mem event cleanup has to go here because the rings 
          * have to be put before we call put_domain. */
@@ -870,6 +875,96 @@ int vcpu_reset(struct vcpu *v)
     return rc;
 }
 
+/*
+ * Map a guest page in and point the vcpu_info pointer at it.  This
+ * makes sure that the vcpu_info is always pointing at a valid piece
+ * of memory, and it sets a pending event to make sure that a pending
+ * event doesn't get missed.
+ */
+int map_vcpu_info(struct vcpu *v, unsigned long gfn, unsigned offset)
+{
+    struct domain *d = v->domain;
+    void *mapping;
+    vcpu_info_t *new_info;
+    struct page_info *page;
+    int i;
+
+    if ( offset > (PAGE_SIZE - sizeof(vcpu_info_t)) )
+        return -EINVAL;
+
+    if ( v->vcpu_info_mfn != INVALID_MFN )
+        return -EINVAL;
+
+    /* Run this command on yourself or on other offline VCPUS. */
+    if ( (v != current) && !test_bit(_VPF_down, &v->pause_flags) )
+        return -EINVAL;
+
+    page = get_page_from_gfn(d, gfn, NULL, P2M_ALLOC);
+    if ( !page )
+        return -EINVAL;
+
+    if ( !get_page_type(page, PGT_writable_page) )
+    {
+        put_page(page);
+        return -EINVAL;
+    }
+
+    mapping = __map_domain_page_global(page);
+    if ( mapping == NULL )
+    {
+        put_page_and_type(page);
+        return -ENOMEM;
+    }
+
+    new_info = (vcpu_info_t *)(mapping + offset);
+
+    if ( v->vcpu_info == &dummy_vcpu_info )
+    {
+        memset(new_info, 0, sizeof(*new_info));
+        __vcpu_info(v, new_info, evtchn_upcall_mask) = 1;
+    }
+    else
+    {
+        memcpy(new_info, v->vcpu_info, sizeof(*new_info));
+    }
+
+    v->vcpu_info = new_info;
+    v->vcpu_info_mfn = page_to_mfn(page);
+
+    /* Set new vcpu_info pointer /before/ setting pending flags. */
+    wmb();
+
+    /*
+     * Mark everything as being pending just to make sure nothing gets
+     * lost.  The domain will get a spurious event, but it can cope.
+     */
+    vcpu_info(v, evtchn_upcall_pending) = 1;
+    for ( i = 0; i < BITS_PER_EVTCHN_WORD(d); i++ )
+        set_bit(i, &vcpu_info(v, evtchn_pending_sel));
+
+    return 0;
+}
+
+/*
+ * Unmap the vcpu info page if the guest decided to place it somewhere
+ * else.  This is only used from arch_domain_destroy, so there's no
+ * need to do anything clever.
+ */
+void unmap_vcpu_info(struct vcpu *v)
+{
+    unsigned long mfn;
+
+    if ( v->vcpu_info_mfn == INVALID_MFN )
+        return;
+
+    mfn = v->vcpu_info_mfn;
+    unmap_domain_page_global(v->vcpu_info);
+
+    v->vcpu_info = &dummy_vcpu_info;
+    v->vcpu_info_mfn = INVALID_MFN;
+
+    put_page_and_type(mfn_to_page(mfn));
+}
 
 long do_vcpu_op(int cmd, int vcpuid, XEN_GUEST_HANDLE_PARAM(void) arg)
 {
@@ -994,6 +1089,22 @@ long do_vcpu_op(int cmd, int vcpuid, XEN_GUEST_HANDLE_PARAM(void) arg)
 
         break;
 
+    case VCPUOP_register_vcpu_info:
+    {
+        struct domain *d = v->domain;
+        struct vcpu_register_vcpu_info info;
+
+        rc = -EFAULT;
+        if ( copy_from_guest(&info, arg, 1) )
+            break;
+
+        domain_lock(d);
+        rc = map_vcpu_info(v, info.mfn, info.offset);
+        domain_unlock(d);
+
+        break;
+    }
+
 #ifdef VCPU_TRAP_NMI
     case VCPUOP_send_nmi:
         if ( !guest_handle_is_null(arg) )

xen/include/asm-x86/domain.h

@@ -436,9 +436,6 @@ struct arch_vcpu
 
     struct paging_vcpu paging;
 
-    /* Guest-specified relocation of vcpu_info. */
-    unsigned long vcpu_info_mfn;
-
     uint32_t gdbsx_vcpu_event;
 
     /* A secondary copy of the vcpu time info. */

xen/include/xen/domain.h

@@ -52,6 +52,9 @@ void free_pirq_struct(void *);
 int  vcpu_initialise(struct vcpu *v);
 void vcpu_destroy(struct vcpu *v);
 
+int map_vcpu_info(struct vcpu *v, unsigned long gfn, unsigned offset);
+void unmap_vcpu_info(struct vcpu *v);
+
 int arch_domain_create(struct domain *d, unsigned int domcr_flags);
 
 void arch_domain_destroy(struct domain *d);

xen/include/xen/sched.h

@@ -192,6 +192,9 @@ struct vcpu
 
     struct waitqueue_vcpu *waitqueue_vcpu;
 
+    /* Guest-specified relocation of vcpu_info. */
+    unsigned long vcpu_info_mfn;
+
     struct arch_vcpu arch;
 };