-static void __init xen_reserve_top(void)
-{
-#ifdef CONFIG_X86_32
- unsigned long top = HYPERVISOR_VIRT_START;
- struct xen_platform_parameters pp;
-
- if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0)
- top = pp.virt_start;
-
- reserve_top_address(-top);
-#endif /* CONFIG_X86_32 */
-}
-
-/*
- * Like __va(), but returns address in the kernel mapping (which is
- * all we have until the physical memory mapping has been set up.
- */
-static void *__ka(phys_addr_t paddr)
-{
-#ifdef CONFIG_X86_64
- return (void *)(paddr + __START_KERNEL_map);
-#else
- return __va(paddr);
-#endif
-}
-
-/* Convert a machine address to physical address */
-static unsigned long m2p(phys_addr_t maddr)
-{
- phys_addr_t paddr;
-
- maddr &= PTE_PFN_MASK;
- paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT;
-
- return paddr;
-}
-
-/* Convert a machine address to kernel virtual */
-static void *m2v(phys_addr_t maddr)
-{
- return __ka(m2p(maddr));
-}
-
-static void set_page_prot(void *addr, pgprot_t prot)
-{
- unsigned long pfn = __pa(addr) >> PAGE_SHIFT;
- pte_t pte = pfn_pte(pfn, prot);
-
- if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0))
- BUG();
-}
-
-static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
-{
- unsigned pmdidx, pteidx;
- unsigned ident_pte;
- unsigned long pfn;
-
- ident_pte = 0;
- pfn = 0;
- for (pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) {
- pte_t *pte_page;
-
- /* Reuse or allocate a page of ptes */
- if (pmd_present(pmd[pmdidx]))
- pte_page = m2v(pmd[pmdidx].pmd);
- else {
- /* Check for free pte pages */
- if (ident_pte == ARRAY_SIZE(level1_ident_pgt))
- break;
-
- pte_page = &level1_ident_pgt[ident_pte];
- ident_pte += PTRS_PER_PTE;
-
- pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE);
- }
-
- /* Install mappings */
- for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
- pte_t pte;
-
- if (pfn > max_pfn_mapped)
- max_pfn_mapped = pfn;
-
- if (!pte_none(pte_page[pteidx]))
- continue;
-
- pte = pfn_pte(pfn, PAGE_KERNEL_EXEC);
- pte_page[pteidx] = pte;
- }
- }
-
- for (pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE)
- set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO);
-
- set_page_prot(pmd, PAGE_KERNEL_RO);
-}
-
-#ifdef CONFIG_X86_64
-static void convert_pfn_mfn(void *v)
-{
- pte_t *pte = v;
- int i;
-
- /* All levels are converted the same way, so just treat them
- as ptes. */
- for (i = 0; i < PTRS_PER_PTE; i++)
- pte[i] = xen_make_pte(pte[i].pte);
-}
-
-/*
- * Set up the inital kernel pagetable.
- *
- * We can construct this by grafting the Xen provided pagetable into
- * head_64.S's preconstructed pagetables. We copy the Xen L2's into
- * level2_ident_pgt, level2_kernel_pgt and level2_fixmap_pgt. This
- * means that only the kernel has a physical mapping to start with -
- * but that's enough to get __va working. We need to fill in the rest
- * of the physical mapping once some sort of allocator has been set
- * up.
- */
-static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
- unsigned long max_pfn)
-{
- pud_t *l3;
- pmd_t *l2;
-
- /* Zap identity mapping */
- init_level4_pgt[0] = __pgd(0);
-
- /* Pre-constructed entries are in pfn, so convert to mfn */
- convert_pfn_mfn(init_level4_pgt);
- convert_pfn_mfn(level3_ident_pgt);
- convert_pfn_mfn(level3_kernel_pgt);
-
- l3 = m2v(pgd[pgd_index(__START_KERNEL_map)].pgd);
- l2 = m2v(l3[pud_index(__START_KERNEL_map)].pud);
-
- memcpy(level2_ident_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
- memcpy(level2_kernel_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
-
- l3 = m2v(pgd[pgd_index(__START_KERNEL_map + PMD_SIZE)].pgd);
- l2 = m2v(l3[pud_index(__START_KERNEL_map + PMD_SIZE)].pud);
- memcpy(level2_fixmap_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD);
-
- /* Set up identity map */
- xen_map_identity_early(level2_ident_pgt, max_pfn);
-
- /* Make pagetable pieces RO */
- set_page_prot(init_level4_pgt, PAGE_KERNEL_RO);
- set_page_prot(level3_ident_pgt, PAGE_KERNEL_RO);
- set_page_prot(level3_kernel_pgt, PAGE_KERNEL_RO);
- set_page_prot(level3_user_vsyscall, PAGE_KERNEL_RO);
- set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
- set_page_prot(level2_fixmap_pgt, PAGE_KERNEL_RO);
-
- /* Pin down new L4 */
- pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE,
- PFN_DOWN(__pa_symbol(init_level4_pgt)));
-
- /* Unpin Xen-provided one */
- pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
-
- /* Switch over */
- pgd = init_level4_pgt;
-
- /*
- * At this stage there can be no user pgd, and no page
- * structure to attach it to, so make sure we just set kernel
- * pgd.
- */
- xen_mc_batch();
- __xen_write_cr3(true, __pa(pgd));
- xen_mc_issue(PARAVIRT_LAZY_CPU);
-
- reserve_early(__pa(xen_start_info->pt_base),
- __pa(xen_start_info->pt_base +
- xen_start_info->nr_pt_frames * PAGE_SIZE),
- "XEN PAGETABLES");
-
- return pgd;
-}
-#else /* !CONFIG_X86_64 */
-static pmd_t level2_kernel_pgt[PTRS_PER_PMD] __page_aligned_bss;
-
-static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
- unsigned long max_pfn)
-{
- pmd_t *kernel_pmd;
-
- init_pg_tables_start = __pa(pgd);
- init_pg_tables_end = __pa(pgd) + xen_start_info->nr_pt_frames*PAGE_SIZE;
- max_pfn_mapped = PFN_DOWN(init_pg_tables_end + 512*1024);
-
- kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
- memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);
-
- xen_map_identity_early(level2_kernel_pgt, max_pfn);
-
- memcpy(swapper_pg_dir, pgd, sizeof(pgd_t) * PTRS_PER_PGD);
- set_pgd(&swapper_pg_dir[KERNEL_PGD_BOUNDARY],
- __pgd(__pa(level2_kernel_pgt) | _PAGE_PRESENT));
-
- set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO);
- set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO);
- set_page_prot(empty_zero_page, PAGE_KERNEL_RO);
-
- pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd)));
-
- xen_write_cr3(__pa(swapper_pg_dir));
-
- pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(swapper_pg_dir)));
-
- return swapper_pg_dir;
-}
-#endif /* CONFIG_X86_64 */
-