+/*
+ * Just beyond the highest usermode address. STACK_TOP_MAX has a
+ * redzone above it, so round it up to a PGD boundary.
+ */
+#define USER_LIMIT ((STACK_TOP_MAX + PGDIR_SIZE - 1) & PGDIR_MASK)
+
+
+#define P2M_ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(unsigned long))
+#define TOP_ENTRIES (MAX_DOMAIN_PAGES / P2M_ENTRIES_PER_PAGE)
+
+/* Placeholder for holes in the address space */
+static unsigned long p2m_missing[P2M_ENTRIES_PER_PAGE] __page_aligned_data =
+ { [ 0 ... P2M_ENTRIES_PER_PAGE-1 ] = ~0UL };
+
+ /* Array of pointers to pages containing p2m entries */
+static unsigned long *p2m_top[TOP_ENTRIES] __page_aligned_data =
+ { [ 0 ... TOP_ENTRIES - 1] = &p2m_missing[0] };
+
+/* Arrays of p2m arrays expressed in mfns used for save/restore */
+static unsigned long p2m_top_mfn[TOP_ENTRIES] __page_aligned_bss;
+
+static unsigned long p2m_top_mfn_list[TOP_ENTRIES / P2M_ENTRIES_PER_PAGE]
+ __page_aligned_bss;
+
+static inline unsigned p2m_top_index(unsigned long pfn)
+{
+ BUG_ON(pfn >= MAX_DOMAIN_PAGES);
+ return pfn / P2M_ENTRIES_PER_PAGE;
+}
+
+static inline unsigned p2m_index(unsigned long pfn)
+{
+ return pfn % P2M_ENTRIES_PER_PAGE;
+}
+
+/* Build the parallel p2m_top_mfn structures */
+void xen_setup_mfn_list_list(void)
+{
+ unsigned pfn, idx;
+
+ for(pfn = 0; pfn < MAX_DOMAIN_PAGES; pfn += P2M_ENTRIES_PER_PAGE) {
+ unsigned topidx = p2m_top_index(pfn);
+
+ p2m_top_mfn[topidx] = virt_to_mfn(p2m_top[topidx]);
+ }
+
+ for(idx = 0; idx < ARRAY_SIZE(p2m_top_mfn_list); idx++) {
+ unsigned topidx = idx * P2M_ENTRIES_PER_PAGE;
+ p2m_top_mfn_list[idx] = virt_to_mfn(&p2m_top_mfn[topidx]);
+ }
+
+ BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
+
+ HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list =
+ virt_to_mfn(p2m_top_mfn_list);
+ HYPERVISOR_shared_info->arch.max_pfn = xen_start_info->nr_pages;
+}
+
+/* Set up p2m_top to point to the domain-builder provided p2m pages */
+void __init xen_build_dynamic_phys_to_machine(void)
+{
+ unsigned long *mfn_list = (unsigned long *)xen_start_info->mfn_list;
+ unsigned long max_pfn = min(MAX_DOMAIN_PAGES, xen_start_info->nr_pages);
+ unsigned pfn;
+
+ for(pfn = 0; pfn < max_pfn; pfn += P2M_ENTRIES_PER_PAGE) {
+ unsigned topidx = p2m_top_index(pfn);
+
+ p2m_top[topidx] = &mfn_list[pfn];
+ }
+}
+
+unsigned long get_phys_to_machine(unsigned long pfn)
+{
+ unsigned topidx, idx;
+
+ if (unlikely(pfn >= MAX_DOMAIN_PAGES))
+ return INVALID_P2M_ENTRY;
+
+ topidx = p2m_top_index(pfn);
+ idx = p2m_index(pfn);
+ return p2m_top[topidx][idx];
+}
+EXPORT_SYMBOL_GPL(get_phys_to_machine);
+
+static void alloc_p2m(unsigned long **pp, unsigned long *mfnp)
+{
+ unsigned long *p;
+ unsigned i;
+
+ p = (void *)__get_free_page(GFP_KERNEL | __GFP_NOFAIL);
+ BUG_ON(p == NULL);
+
+ for(i = 0; i < P2M_ENTRIES_PER_PAGE; i++)
+ p[i] = INVALID_P2M_ENTRY;
+
+ if (cmpxchg(pp, p2m_missing, p) != p2m_missing)
+ free_page((unsigned long)p);
+ else
+ *mfnp = virt_to_mfn(p);
+}
+
+void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
+{
+ unsigned topidx, idx;
+
+ if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) {
+ BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
+ return;
+ }
+
+ if (unlikely(pfn >= MAX_DOMAIN_PAGES)) {
+ BUG_ON(mfn != INVALID_P2M_ENTRY);
+ return;
+ }
+
+ topidx = p2m_top_index(pfn);
+ if (p2m_top[topidx] == p2m_missing) {
+ /* no need to allocate a page to store an invalid entry */
+ if (mfn == INVALID_P2M_ENTRY)
+ return;
+ alloc_p2m(&p2m_top[topidx], &p2m_top_mfn[topidx]);
+ }
+
+ idx = p2m_index(pfn);
+ p2m_top[topidx][idx] = mfn;
+}
+
+xmaddr_t arbitrary_virt_to_machine(void *vaddr)