diff options
Diffstat (limited to 'arch/x86/xen/mmu.c')
-rw-r--r-- | arch/x86/xen/mmu.c | 86 |
1 files changed, 72 insertions, 14 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index c237b810b03f..a1feff9e59b6 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -2034,6 +2034,20 @@ static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) set_page_prot(pmd, PAGE_KERNEL_RO); } +void __init xen_setup_machphys_mapping(void) +{ + struct xen_machphys_mapping mapping; + unsigned long machine_to_phys_nr_ents; + + if (HYPERVISOR_memory_op(XENMEM_machphys_mapping, &mapping) == 0) { + machine_to_phys_mapping = (unsigned long *)mapping.v_start; + machine_to_phys_nr_ents = mapping.max_mfn + 1; + } else { + machine_to_phys_nr_ents = MACH2PHYS_NR_ENTRIES; + } + machine_to_phys_order = fls(machine_to_phys_nr_ents - 1); +} + #ifdef CONFIG_X86_64 static void convert_pfn_mfn(void *v) { @@ -2119,44 +2133,83 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, return pgd; } #else /* !CONFIG_X86_64 */ -static RESERVE_BRK_ARRAY(pmd_t, level2_kernel_pgt, PTRS_PER_PMD); +static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD); +static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD); + +static __init void xen_write_cr3_init(unsigned long cr3) +{ + unsigned long pfn = PFN_DOWN(__pa(swapper_pg_dir)); + + BUG_ON(read_cr3() != __pa(initial_page_table)); + BUG_ON(cr3 != __pa(swapper_pg_dir)); + + /* + * We are switching to swapper_pg_dir for the first time (from + * initial_page_table) and therefore need to mark that page + * read-only and then pin it. + * + * Xen disallows sharing of kernel PMDs for PAE + * guests. Therefore we must copy the kernel PMD from + * initial_page_table into a new kernel PMD to be used in + * swapper_pg_dir. + */ + swapper_kernel_pmd = + extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE); + memcpy(swapper_kernel_pmd, initial_kernel_pmd, + sizeof(pmd_t) * PTRS_PER_PMD); + swapper_pg_dir[KERNEL_PGD_BOUNDARY] = + __pgd(__pa(swapper_kernel_pmd) | _PAGE_PRESENT); + set_page_prot(swapper_kernel_pmd, PAGE_KERNEL_RO); + + set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO); + xen_write_cr3(cr3); + pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, pfn); + + pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, + PFN_DOWN(__pa(initial_page_table))); + set_page_prot(initial_page_table, PAGE_KERNEL); + set_page_prot(initial_kernel_pmd, PAGE_KERNEL); + + pv_mmu_ops.write_cr3 = &xen_write_cr3; +} __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) { pmd_t *kernel_pmd; - level2_kernel_pgt = extend_brk(sizeof(pmd_t *) * PTRS_PER_PMD, PAGE_SIZE); + initial_kernel_pmd = + extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE); max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) + xen_start_info->nr_pt_frames * PAGE_SIZE + 512*1024); kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd); - memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD); + memcpy(initial_kernel_pmd, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD); - xen_map_identity_early(level2_kernel_pgt, max_pfn); + xen_map_identity_early(initial_kernel_pmd, 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)); + memcpy(initial_page_table, pgd, sizeof(pgd_t) * PTRS_PER_PGD); + initial_page_table[KERNEL_PGD_BOUNDARY] = + __pgd(__pa(initial_kernel_pmd) | _PAGE_PRESENT); - set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO); - set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO); + set_page_prot(initial_kernel_pmd, PAGE_KERNEL_RO); + set_page_prot(initial_page_table, 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))); + pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, + PFN_DOWN(__pa(initial_page_table))); + xen_write_cr3(__pa(initial_page_table)); memblock_x86_reserve_range(__pa(xen_start_info->pt_base), __pa(xen_start_info->pt_base + xen_start_info->nr_pt_frames * PAGE_SIZE), "XEN PAGETABLES"); - return swapper_pg_dir; + return initial_page_table; } #endif /* CONFIG_X86_64 */ @@ -2290,7 +2343,11 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = { .write_cr2 = xen_write_cr2, .read_cr3 = xen_read_cr3, +#ifdef CONFIG_X86_32 + .write_cr3 = xen_write_cr3_init, +#else .write_cr3 = xen_write_cr3, +#endif .flush_tlb_user = xen_flush_tlb, .flush_tlb_kernel = xen_flush_tlb, @@ -2627,7 +2684,8 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma, prot = __pgprot(pgprot_val(prot) | _PAGE_IOMAP); - vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP; + BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_RESERVED | VM_IO)) == + (VM_PFNMAP | VM_RESERVED | VM_IO))); rmd.mfn = mfn; rmd.prot = prot; |