*/
#define USER_LIMIT ((STACK_TOP_MAX + PGDIR_SIZE - 1) & PGDIR_MASK)
-/*
- * Xen leaves the responsibility for maintaining p2m mappings to the
- * guests themselves, but it must also access and update the p2m array
- * during suspend/resume when all the pages are reallocated.
- *
- * The p2m table is logically a flat array, but we implement it as a
- * three-level tree to allow the address space to be sparse.
- *
- * Xen
- * |
- * p2m_top p2m_top_mfn
- * / \ / \
- * p2m_mid p2m_mid p2m_mid_mfn p2m_mid_mfn
- * / \ / \ / /
- * p2m p2m p2m p2m p2m p2m p2m ...
- *
- * The p2m_mid_mfn pages are mapped by p2m_top_mfn_p.
- *
- * The p2m_top and p2m_top_mfn levels are limited to 1 page, so the
- * maximum representable pseudo-physical address space is:
- * P2M_TOP_PER_PAGE * P2M_MID_PER_PAGE * P2M_PER_PAGE pages
- *
- * P2M_PER_PAGE depends on the architecture, as a mfn is always
- * unsigned long (8 bytes on 64-bit, 4 bytes on 32), leading to
- * 512 and 1024 entries respectively.
- */
-
-unsigned long xen_max_p2m_pfn __read_mostly;
-
-#define P2M_PER_PAGE (PAGE_SIZE / sizeof(unsigned long))
-#define P2M_MID_PER_PAGE (PAGE_SIZE / sizeof(unsigned long *))
-#define P2M_TOP_PER_PAGE (PAGE_SIZE / sizeof(unsigned long **))
-
-#define MAX_P2M_PFN (P2M_TOP_PER_PAGE * P2M_MID_PER_PAGE * P2M_PER_PAGE)
-
-/* Placeholders for holes in the address space */
-static RESERVE_BRK_ARRAY(unsigned long, p2m_missing, P2M_PER_PAGE);
-static RESERVE_BRK_ARRAY(unsigned long *, p2m_mid_missing, P2M_MID_PER_PAGE);
-static RESERVE_BRK_ARRAY(unsigned long, p2m_mid_missing_mfn, P2M_MID_PER_PAGE);
-
-static RESERVE_BRK_ARRAY(unsigned long **, p2m_top, P2M_TOP_PER_PAGE);
-static RESERVE_BRK_ARRAY(unsigned long, p2m_top_mfn, P2M_TOP_PER_PAGE);
-static RESERVE_BRK_ARRAY(unsigned long *, p2m_top_mfn_p, P2M_TOP_PER_PAGE);
-
-RESERVE_BRK(p2m_mid, PAGE_SIZE * (MAX_DOMAIN_PAGES / (P2M_PER_PAGE * P2M_MID_PER_PAGE)));
-RESERVE_BRK(p2m_mid_mfn, PAGE_SIZE * (MAX_DOMAIN_PAGES / (P2M_PER_PAGE * P2M_MID_PER_PAGE)));
-
-static inline unsigned p2m_top_index(unsigned long pfn)
-{
- BUG_ON(pfn >= MAX_P2M_PFN);
- return pfn / (P2M_MID_PER_PAGE * P2M_PER_PAGE);
-}
-
-static inline unsigned p2m_mid_index(unsigned long pfn)
-{
- return (pfn / P2M_PER_PAGE) % P2M_MID_PER_PAGE;
-}
-
-static inline unsigned p2m_index(unsigned long pfn)
-{
- return pfn % P2M_PER_PAGE;
-}
-
-static void p2m_top_init(unsigned long ***top)
-{
- unsigned i;
-
- for (i = 0; i < P2M_TOP_PER_PAGE; i++)
- top[i] = p2m_mid_missing;
-}
-
-static void p2m_top_mfn_init(unsigned long *top)
-{
- unsigned i;
-
- for (i = 0; i < P2M_TOP_PER_PAGE; i++)
- top[i] = virt_to_mfn(p2m_mid_missing_mfn);
-}
-
-static void p2m_top_mfn_p_init(unsigned long **top)
-{
- unsigned i;
-
- for (i = 0; i < P2M_TOP_PER_PAGE; i++)
- top[i] = p2m_mid_missing_mfn;
-}
-
-static void p2m_mid_init(unsigned long **mid)
-{
- unsigned i;
-
- for (i = 0; i < P2M_MID_PER_PAGE; i++)
- mid[i] = p2m_missing;
-}
-
-static void p2m_mid_mfn_init(unsigned long *mid)
-{
- unsigned i;
-
- for (i = 0; i < P2M_MID_PER_PAGE; i++)
- mid[i] = virt_to_mfn(p2m_missing);
-}
-
-static void p2m_init(unsigned long *p2m)
-{
- unsigned i;
-
- for (i = 0; i < P2M_MID_PER_PAGE; i++)
- p2m[i] = INVALID_P2M_ENTRY;
-}
-
-/*
- * Build the parallel p2m_top_mfn and p2m_mid_mfn structures
- *
- * This is called both at boot time, and after resuming from suspend:
- * - At boot time we're called very early, and must use extend_brk()
- * to allocate memory.
- *
- * - After resume we're called from within stop_machine, but the mfn
- * tree should alreay be completely allocated.
- */
-void xen_build_mfn_list_list(void)
-{
- unsigned long pfn;
-
- /* Pre-initialize p2m_top_mfn to be completely missing */
- if (p2m_top_mfn == NULL) {
- p2m_mid_missing_mfn = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_mid_mfn_init(p2m_mid_missing_mfn);
-
- p2m_top_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_top_mfn_p_init(p2m_top_mfn_p);
-
- p2m_top_mfn = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_top_mfn_init(p2m_top_mfn);
- } else {
- /* Reinitialise, mfn's all change after migration */
- p2m_mid_mfn_init(p2m_mid_missing_mfn);
- }
-
- for (pfn = 0; pfn < xen_max_p2m_pfn; pfn += P2M_PER_PAGE) {
- unsigned topidx = p2m_top_index(pfn);
- unsigned mididx = p2m_mid_index(pfn);
- unsigned long **mid;
- unsigned long *mid_mfn_p;
-
- mid = p2m_top[topidx];
- mid_mfn_p = p2m_top_mfn_p[topidx];
-
- /* Don't bother allocating any mfn mid levels if
- * they're just missing, just update the stored mfn,
- * since all could have changed over a migrate.
- */
- if (mid == p2m_mid_missing) {
- BUG_ON(mididx);
- BUG_ON(mid_mfn_p != p2m_mid_missing_mfn);
- p2m_top_mfn[topidx] = virt_to_mfn(p2m_mid_missing_mfn);
- pfn += (P2M_MID_PER_PAGE - 1) * P2M_PER_PAGE;
- continue;
- }
-
- if (mid_mfn_p == p2m_mid_missing_mfn) {
- /*
- * XXX boot-time only! We should never find
- * missing parts of the mfn tree after
- * runtime. extend_brk() will BUG if we call
- * it too late.
- */
- mid_mfn_p = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_mid_mfn_init(mid_mfn_p);
-
- p2m_top_mfn_p[topidx] = mid_mfn_p;
- }
-
- p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p);
- mid_mfn_p[mididx] = virt_to_mfn(mid[mididx]);
- }
-}
-
-void xen_setup_mfn_list_list(void)
-{
- 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);
- HYPERVISOR_shared_info->arch.max_pfn = xen_max_p2m_pfn;
-}
-
-/* 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 long pfn;
-
- xen_max_p2m_pfn = max_pfn;
-
- p2m_missing = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_init(p2m_missing);
-
- p2m_mid_missing = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_mid_init(p2m_mid_missing);
-
- p2m_top = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_top_init(p2m_top);
-
- /*
- * The domain builder gives us a pre-constructed p2m array in
- * mfn_list for all the pages initially given to us, so we just
- * need to graft that into our tree structure.
- */
- for (pfn = 0; pfn < max_pfn; pfn += P2M_PER_PAGE) {
- unsigned topidx = p2m_top_index(pfn);
- unsigned mididx = p2m_mid_index(pfn);
-
- if (p2m_top[topidx] == p2m_mid_missing) {
- unsigned long **mid = extend_brk(PAGE_SIZE, PAGE_SIZE);
- p2m_mid_init(mid);
-
- p2m_top[topidx] = mid;
- }
-
- p2m_top[topidx][mididx] = &mfn_list[pfn];
- }
-}
-
-unsigned long get_phys_to_machine(unsigned long pfn)
-{
- unsigned topidx, mididx, idx;
-
- if (unlikely(pfn >= MAX_P2M_PFN))
- return INVALID_P2M_ENTRY;
-
- topidx = p2m_top_index(pfn);
- mididx = p2m_mid_index(pfn);
- idx = p2m_index(pfn);
-
- return p2m_top[topidx][mididx][idx];
-}
-EXPORT_SYMBOL_GPL(get_phys_to_machine);
-
-static void *alloc_p2m_page(void)
-{
- return (void *)__get_free_page(GFP_KERNEL | __GFP_REPEAT);
-}
-
-static void free_p2m_page(void *p)
-{
- free_page((unsigned long)p);
-}
-
-/*
- * Fully allocate the p2m structure for a given pfn. We need to check
- * that both the top and mid levels are allocated, and make sure the
- * parallel mfn tree is kept in sync. We may race with other cpus, so
- * the new pages are installed with cmpxchg; if we lose the race then
- * simply free the page we allocated and use the one that's there.
- */
-static bool alloc_p2m(unsigned long pfn)
-{
- unsigned topidx, mididx;
- unsigned long ***top_p, **mid;
- unsigned long *top_mfn_p, *mid_mfn;
-
- topidx = p2m_top_index(pfn);
- mididx = p2m_mid_index(pfn);
-
- top_p = &p2m_top[topidx];
- mid = *top_p;
-
- if (mid == p2m_mid_missing) {
- /* Mid level is missing, allocate a new one */
- mid = alloc_p2m_page();
- if (!mid)
- return false;
-
- p2m_mid_init(mid);
-
- if (cmpxchg(top_p, p2m_mid_missing, mid) != p2m_mid_missing)
- free_p2m_page(mid);
- }
-
- top_mfn_p = &p2m_top_mfn[topidx];
- mid_mfn = p2m_top_mfn_p[topidx];
-
- BUG_ON(virt_to_mfn(mid_mfn) != *top_mfn_p);
-
- if (mid_mfn == p2m_mid_missing_mfn) {
- /* Separately check the mid mfn level */
- unsigned long missing_mfn;
- unsigned long mid_mfn_mfn;
-
- mid_mfn = alloc_p2m_page();
- if (!mid_mfn)
- return false;
-
- p2m_mid_mfn_init(mid_mfn);
-
- missing_mfn = virt_to_mfn(p2m_mid_missing_mfn);
- mid_mfn_mfn = virt_to_mfn(mid_mfn);
- if (cmpxchg(top_mfn_p, missing_mfn, mid_mfn_mfn) != missing_mfn)
- free_p2m_page(mid_mfn);
- else
- p2m_top_mfn_p[topidx] = mid_mfn;
- }
-
- if (p2m_top[topidx][mididx] == p2m_missing) {
- /* p2m leaf page is missing */
- unsigned long *p2m;
-
- p2m = alloc_p2m_page();
- if (!p2m)
- return false;
-
- p2m_init(p2m);
-
- if (cmpxchg(&mid[mididx], p2m_missing, p2m) != p2m_missing)
- free_p2m_page(p2m);
- else
- mid_mfn[mididx] = virt_to_mfn(p2m);
- }
-
- return true;
-}
-
-/* Try to install p2m mapping; fail if intermediate bits missing */
-bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
-{
- unsigned topidx, mididx, idx;
-
- if (unlikely(pfn >= MAX_P2M_PFN)) {
- BUG_ON(mfn != INVALID_P2M_ENTRY);
- return true;
- }
-
- topidx = p2m_top_index(pfn);
- mididx = p2m_mid_index(pfn);
- idx = p2m_index(pfn);
-
- if (p2m_top[topidx][mididx] == p2m_missing)
- return mfn == INVALID_P2M_ENTRY;
-
- p2m_top[topidx][mididx][idx] = mfn;
-
- return true;
-}
-
-bool set_phys_to_machine(unsigned long pfn, unsigned long mfn)
-{
- if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) {
- BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
- return true;
- }
-
- if (unlikely(!__set_phys_to_machine(pfn, mfn))) {
- if (!alloc_p2m(pfn))
- return false;
-
- if (!__set_phys_to_machine(pfn, mfn))
- return false;
- }
-
- return true;
-}
-
unsigned long arbitrary_virt_to_mfn(void *vaddr)
{
xmaddr_t maddr = arbitrary_virt_to_machine(vaddr);
offset = address & ~PAGE_MASK;
return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
}
+EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine);
void make_lowmem_page_readonly(void *vaddr)
{
*/
void xen_mm_pin_all(void)
{
- unsigned long flags;
struct page *page;
- spin_lock_irqsave(&pgd_lock, flags);
+ spin_lock(&pgd_lock);
list_for_each_entry(page, &pgd_list, lru) {
if (!PagePinned(page)) {
}
}
- spin_unlock_irqrestore(&pgd_lock, flags);
+ spin_unlock(&pgd_lock);
}
/*
*/
void xen_mm_unpin_all(void)
{
- unsigned long flags;
struct page *page;
- spin_lock_irqsave(&pgd_lock, flags);
+ spin_lock(&pgd_lock);
list_for_each_entry(page, &pgd_list, lru) {
if (PageSavePinned(page)) {
}
}
- spin_unlock_irqrestore(&pgd_lock, flags);
+ spin_unlock(&pgd_lock);
}
void xen_activate_mm(struct mm_struct *prev, struct mm_struct *next)
active_mm = percpu_read(cpu_tlbstate.active_mm);
- if (active_mm == mm)
+ if (active_mm == mm && percpu_read(cpu_tlbstate.state) != TLBSTATE_OK)
leave_mm(smp_processor_id());
/* If this cpu still has a stale cr3 reference, then make sure
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;
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)
{
pud_t *l3;
pmd_t *l2;
+ /* max_pfn_mapped is the last pfn mapped in the initial memory
+ * mappings. Considering that on Xen after the kernel mappings we
+ * have the mappings of some pages that don't exist in pfn space, we
+ * set max_pfn_mapped to the last real pfn mapped. */
+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
+
/* Zap identity mapping */
init_level4_pgt[0] = __pgd(0);
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);
+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
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 */
.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,
x86_init.paging.pagetable_setup_done = xen_pagetable_setup_done;
pv_mmu_ops = xen_mmu_ops;
- vmap_lazy_unmap = false;
-
memset(dummy_mapping, 0xff, PAGE_SIZE);
}
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;
projects / linux-flexiantxendom0-natty.git / blobdiff