DEFINE_PER_CPU(unsigned long, xen_cr3); /* cr3 stored as physaddr */
DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */
+static phys_addr_t xen_pt_base, xen_pt_size __initdata;
/*
* Just beyond the highest usermode address. STACK_TOP_MAX has a
static void xen_post_allocator_init(void);
+static void __init pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
+{
+ struct mmuext_op op;
+
+ op.cmd = cmd;
+ op.arg1.mfn = pfn_to_mfn(pfn);
+ if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
+ BUG();
+}
+
#ifdef CONFIG_X86_64
static void __init xen_cleanhighmap(unsigned long vaddr,
unsigned long vaddr_end)
xen_mc_flush();
}
+/*
+ * Make a page range writeable and free it.
+ */
+static void __init xen_free_ro_pages(unsigned long paddr, unsigned long size)
+{
+ void *vaddr = __va(paddr);
+ void *vaddr_end = vaddr + size;
+
+ for (; vaddr < vaddr_end; vaddr += PAGE_SIZE)
+ make_lowmem_page_readwrite(vaddr);
+
+ memblock_free(paddr, size);
+}
+
+static void __init xen_cleanmfnmap_free_pgtbl(void *pgtbl, bool unpin)
+{
+ unsigned long pa = __pa(pgtbl) & PHYSICAL_PAGE_MASK;
+
+ if (unpin)
+ pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(pa));
+ ClearPagePinned(virt_to_page(__va(pa)));
+ xen_free_ro_pages(pa, PAGE_SIZE);
+}
+
+/*
+ * Since it is well isolated we can (and since it is perhaps large we should)
+ * also free the page tables mapping the initial P->M table.
+ */
+static void __init xen_cleanmfnmap(unsigned long vaddr)
+{
+ unsigned long va = vaddr & PMD_MASK;
+ unsigned long pa;
+ pgd_t *pgd = pgd_offset_k(va);
+ pud_t *pud_page = pud_offset(pgd, 0);
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ unsigned int i;
+ bool unpin;
+
+ unpin = (vaddr == 2 * PGDIR_SIZE);
+ set_pgd(pgd, __pgd(0));
+ do {
+ pud = pud_page + pud_index(va);
+ if (pud_none(*pud)) {
+ va += PUD_SIZE;
+ } else if (pud_large(*pud)) {
+ pa = pud_val(*pud) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, PUD_SIZE);
+ va += PUD_SIZE;
+ } else {
+ pmd = pmd_offset(pud, va);
+ if (pmd_large(*pmd)) {
+ pa = pmd_val(*pmd) & PHYSICAL_PAGE_MASK;
+ xen_free_ro_pages(pa, PMD_SIZE);
+ } else if (!pmd_none(*pmd)) {
+ pte = pte_offset_kernel(pmd, va);
+ set_pmd(pmd, __pmd(0));
+ for (i = 0; i < PTRS_PER_PTE; ++i) {
+ if (pte_none(pte[i]))
+ break;
+ pa = pte_pfn(pte[i]) << PAGE_SHIFT;
+ xen_free_ro_pages(pa, PAGE_SIZE);
+ }
+ xen_cleanmfnmap_free_pgtbl(pte, unpin);
+ }
+ va += PMD_SIZE;
+ if (pmd_index(va))
+ continue;
+ set_pud(pud, __pud(0));
+ xen_cleanmfnmap_free_pgtbl(pmd, unpin);
+ }
+
+ } while (pud_index(va) || pmd_index(va));
+ xen_cleanmfnmap_free_pgtbl(pud_page, unpin);
+}
+
static void __init xen_pagetable_p2m_free(void)
{
unsigned long size;
/* using __ka address and sticking INVALID_P2M_ENTRY! */
memset((void *)xen_start_info->mfn_list, 0xff, size);
- /* We should be in __ka space. */
- BUG_ON(xen_start_info->mfn_list < __START_KERNEL_map);
addr = xen_start_info->mfn_list;
- /* We roundup to the PMD, which means that if anybody at this stage is
- * using the __ka address of xen_start_info or xen_start_info->shared_info
- * they are in going to crash. Fortunatly we have already revectored
- * in xen_setup_kernel_pagetable and in xen_setup_shared_info. */
+ /*
+ * We could be in __ka space.
+ * We roundup to the PMD, which means that if anybody at this stage is
+ * using the __ka address of xen_start_info or
+ * xen_start_info->shared_info they are in going to crash. Fortunatly
+ * we have already revectored in xen_setup_kernel_pagetable and in
+ * xen_setup_shared_info.
+ */
size = roundup(size, PMD_SIZE);
- xen_cleanhighmap(addr, addr + size);
- size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
- memblock_free(__pa(xen_start_info->mfn_list), size);
+ if (addr >= __START_KERNEL_map) {
+ xen_cleanhighmap(addr, addr + size);
+ size = PAGE_ALIGN(xen_start_info->nr_pages *
+ sizeof(unsigned long));
+ memblock_free(__pa(addr), size);
+ } else {
+ xen_cleanmfnmap(addr);
+ }
+}
+
+static void __init xen_pagetable_cleanhighmap(void)
+{
+ unsigned long size;
+ unsigned long addr;
/* At this stage, cleanup_highmap has already cleaned __ka space
* from _brk_limit way up to the max_pfn_mapped (which is the end of
#ifdef CONFIG_X86_64
xen_pagetable_p2m_free();
+
+ xen_pagetable_cleanhighmap();
#endif
/* And revector! Bye bye old array */
xen_start_info->mfn_list = (unsigned long)xen_p2m_addr;
#else /* CONFIG_X86_64 */
static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
{
+ unsigned long pfn;
+
+ if (xen_feature(XENFEAT_writable_page_tables) ||
+ xen_feature(XENFEAT_auto_translated_physmap) ||
+ xen_start_info->mfn_list >= __START_KERNEL_map)
+ return pte;
+
+ /*
+ * Pages belonging to the initial p2m list mapped outside the default
+ * address range must be mapped read-only. This region contains the
+ * page tables for mapping the p2m list, too, and page tables MUST be
+ * mapped read-only.
+ */
+ pfn = pte_pfn(pte);
+ if (pfn >= xen_start_info->first_p2m_pfn &&
+ pfn < xen_start_info->first_p2m_pfn + xen_start_info->nr_p2m_frames)
+ pte = __pte_ma(pte_val_ma(pte) & ~_PAGE_RW);
+
return pte;
}
#endif /* CONFIG_X86_64 */
native_set_pte(ptep, pte);
}
-static void __init pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
-{
- struct mmuext_op op;
- op.cmd = cmd;
- op.arg1.mfn = pfn_to_mfn(pfn);
- if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
- BUG();
-}
-
/* Early in boot, while setting up the initial pagetable, assume
everything is pinned. */
static void __init xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
* 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));
+ if (xen_start_info->mfn_list < __START_KERNEL_map)
+ max_pfn_mapped = xen_start_info->first_p2m_pfn;
+ else
+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
pt_base = PFN_DOWN(__pa(xen_start_info->pt_base));
pt_end = pt_base + xen_start_info->nr_pt_frames;
/* Graft it onto L4[511][510] */
copy_page(level2_kernel_pgt, l2);
+ /* Copy the initial P->M table mappings if necessary. */
+ i = pgd_index(xen_start_info->mfn_list);
+ if (i && i < pgd_index(__START_KERNEL_map))
+ init_level4_pgt[i] = ((pgd_t *)xen_start_info->pt_base)[i];
+
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
/* Make pagetable pieces RO */
set_page_prot(init_level4_pgt, PAGE_KERNEL_RO);
check_pt_base(&pt_base, &pt_end, addr[i]);
/* Our (by three pages) smaller Xen pagetable that we are using */
- memblock_reserve(PFN_PHYS(pt_base), (pt_end - pt_base) * PAGE_SIZE);
+ xen_pt_base = PFN_PHYS(pt_base);
+ xen_pt_size = (pt_end - pt_base) * PAGE_SIZE;
+ memblock_reserve(xen_pt_base, xen_pt_size);
+
/* Revector the xen_start_info */
xen_start_info = (struct start_info *)__va(__pa(xen_start_info));
}
+
+/*
+ * Read a value from a physical address.
+ */
+static unsigned long __init xen_read_phys_ulong(phys_addr_t addr)
+{
+ unsigned long *vaddr;
+ unsigned long val;
+
+ vaddr = early_memremap_ro(addr, sizeof(val));
+ val = *vaddr;
+ early_memunmap(vaddr, sizeof(val));
+ return val;
+}
+
+/*
+ * Translate a virtual address to a physical one without relying on mapped
+ * page tables.
+ */
+static phys_addr_t __init xen_early_virt_to_phys(unsigned long vaddr)
+{
+ phys_addr_t pa;
+ pgd_t pgd;
+ pud_t pud;
+ pmd_t pmd;
+ pte_t pte;
+
+ pa = read_cr3();
+ pgd = native_make_pgd(xen_read_phys_ulong(pa + pgd_index(vaddr) *
+ sizeof(pgd)));
+ if (!pgd_present(pgd))
+ return 0;
+
+ pa = pgd_val(pgd) & PTE_PFN_MASK;
+ pud = native_make_pud(xen_read_phys_ulong(pa + pud_index(vaddr) *
+ sizeof(pud)));
+ if (!pud_present(pud))
+ return 0;
+ pa = pud_pfn(pud) << PAGE_SHIFT;
+ if (pud_large(pud))
+ return pa + (vaddr & ~PUD_MASK);
+
+ pmd = native_make_pmd(xen_read_phys_ulong(pa + pmd_index(vaddr) *
+ sizeof(pmd)));
+ if (!pmd_present(pmd))
+ return 0;
+ pa = pmd_pfn(pmd) << PAGE_SHIFT;
+ if (pmd_large(pmd))
+ return pa + (vaddr & ~PMD_MASK);
+
+ pte = native_make_pte(xen_read_phys_ulong(pa + pte_index(vaddr) *
+ sizeof(pte)));
+ if (!pte_present(pte))
+ return 0;
+ pa = pte_pfn(pte) << PAGE_SHIFT;
+
+ return pa | (vaddr & ~PAGE_MASK);
+}
+
+/*
+ * Find a new area for the hypervisor supplied p2m list and relocate the p2m to
+ * this area.
+ */
+void __init xen_relocate_p2m(void)
+{
+ phys_addr_t size, new_area, pt_phys, pmd_phys, pud_phys;
+ unsigned long p2m_pfn, p2m_pfn_end, n_frames, pfn, pfn_end;
+ int n_pte, n_pt, n_pmd, n_pud, idx_pte, idx_pt, idx_pmd, idx_pud;
+ pte_t *pt;
+ pmd_t *pmd;
+ pud_t *pud;
+ pgd_t *pgd;
+ unsigned long *new_p2m;
+
+ size = PAGE_ALIGN(xen_start_info->nr_pages * sizeof(unsigned long));
+ n_pte = roundup(size, PAGE_SIZE) >> PAGE_SHIFT;
+ n_pt = roundup(size, PMD_SIZE) >> PMD_SHIFT;
+ n_pmd = roundup(size, PUD_SIZE) >> PUD_SHIFT;
+ n_pud = roundup(size, PGDIR_SIZE) >> PGDIR_SHIFT;
+ n_frames = n_pte + n_pt + n_pmd + n_pud;
+
+ new_area = xen_find_free_area(PFN_PHYS(n_frames));
+ if (!new_area) {
+ xen_raw_console_write("Can't find new memory area for p2m needed due to E820 map conflict\n");
+ BUG();
+ }
+
+ /*
+ * Setup the page tables for addressing the new p2m list.
+ * We have asked the hypervisor to map the p2m list at the user address
+ * PUD_SIZE. It may have done so, or it may have used a kernel space
+ * address depending on the Xen version.
+ * To avoid any possible virtual address collision, just use
+ * 2 * PUD_SIZE for the new area.
+ */
+ pud_phys = new_area;
+ pmd_phys = pud_phys + PFN_PHYS(n_pud);
+ pt_phys = pmd_phys + PFN_PHYS(n_pmd);
+ p2m_pfn = PFN_DOWN(pt_phys) + n_pt;
+
+ pgd = __va(read_cr3());
+ new_p2m = (unsigned long *)(2 * PGDIR_SIZE);
+ for (idx_pud = 0; idx_pud < n_pud; idx_pud++) {
+ pud = early_memremap(pud_phys, PAGE_SIZE);
+ clear_page(pud);
+ for (idx_pmd = 0; idx_pmd < min(n_pmd, PTRS_PER_PUD);
+ idx_pmd++) {
+ pmd = early_memremap(pmd_phys, PAGE_SIZE);
+ clear_page(pmd);
+ for (idx_pt = 0; idx_pt < min(n_pt, PTRS_PER_PMD);
+ idx_pt++) {
+ pt = early_memremap(pt_phys, PAGE_SIZE);
+ clear_page(pt);
+ for (idx_pte = 0;
+ idx_pte < min(n_pte, PTRS_PER_PTE);
+ idx_pte++) {
+ set_pte(pt + idx_pte,
+ pfn_pte(p2m_pfn, PAGE_KERNEL));
+ p2m_pfn++;
+ }
+ n_pte -= PTRS_PER_PTE;
+ early_memunmap(pt, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pt_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE,
+ PFN_DOWN(pt_phys));
+ set_pmd(pmd + idx_pt,
+ __pmd(_PAGE_TABLE | pt_phys));
+ pt_phys += PAGE_SIZE;
+ }
+ n_pt -= PTRS_PER_PMD;
+ early_memunmap(pmd, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pmd_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L2_TABLE,
+ PFN_DOWN(pmd_phys));
+ set_pud(pud + idx_pmd, __pud(_PAGE_TABLE | pmd_phys));
+ pmd_phys += PAGE_SIZE;
+ }
+ n_pmd -= PTRS_PER_PUD;
+ early_memunmap(pud, PAGE_SIZE);
+ make_lowmem_page_readonly(__va(pud_phys));
+ pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(pud_phys));
+ set_pgd(pgd + 2 + idx_pud, __pgd(_PAGE_TABLE | pud_phys));
+ pud_phys += PAGE_SIZE;
+ }
+
+ /* Now copy the old p2m info to the new area. */
+ memcpy(new_p2m, xen_p2m_addr, size);
+ xen_p2m_addr = new_p2m;
+
+ /* Release the old p2m list and set new list info. */
+ p2m_pfn = PFN_DOWN(xen_early_virt_to_phys(xen_start_info->mfn_list));
+ BUG_ON(!p2m_pfn);
+ p2m_pfn_end = p2m_pfn + PFN_DOWN(size);
+
+ if (xen_start_info->mfn_list < __START_KERNEL_map) {
+ pfn = xen_start_info->first_p2m_pfn;
+ pfn_end = xen_start_info->first_p2m_pfn +
+ xen_start_info->nr_p2m_frames;
+ set_pgd(pgd + 1, __pgd(0));
+ } else {
+ pfn = p2m_pfn;
+ pfn_end = p2m_pfn_end;
+ }
+
+ memblock_free(PFN_PHYS(pfn), PAGE_SIZE * (pfn_end - pfn));
+ while (pfn < pfn_end) {
+ if (pfn == p2m_pfn) {
+ pfn = p2m_pfn_end;
+ continue;
+ }
+ make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
+ pfn++;
+ }
+
+ xen_start_info->mfn_list = (unsigned long)xen_p2m_addr;
+ xen_start_info->first_p2m_pfn = PFN_DOWN(new_area);
+ xen_start_info->nr_p2m_frames = n_frames;
+}
+
#else /* !CONFIG_X86_64 */
static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD);
static RESERVE_BRK_ARRAY(pmd_t, swapper_kernel_pmd, PTRS_PER_PMD);
pv_mmu_ops.write_cr3 = &xen_write_cr3;
}
+/*
+ * For 32 bit domains xen_start_info->pt_base is the pgd address which might be
+ * not the first page table in the page table pool.
+ * Iterate through the initial page tables to find the real page table base.
+ */
+static phys_addr_t xen_find_pt_base(pmd_t *pmd)
+{
+ phys_addr_t pt_base, paddr;
+ unsigned pmdidx;
+
+ pt_base = min(__pa(xen_start_info->pt_base), __pa(pmd));
+
+ for (pmdidx = 0; pmdidx < PTRS_PER_PMD; pmdidx++)
+ if (pmd_present(pmd[pmdidx]) && !pmd_large(pmd[pmdidx])) {
+ paddr = m2p(pmd[pmdidx].pmd);
+ pt_base = min(pt_base, paddr);
+ }
+
+ return pt_base;
+}
+
void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn)
{
pmd_t *kernel_pmd;
+ kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
+
+ xen_pt_base = xen_find_pt_base(kernel_pmd);
+ xen_pt_size = xen_start_info->nr_pt_frames * 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(xen_pt_base + xen_pt_size + 512 * 1024);
- kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
copy_page(initial_kernel_pmd, kernel_pmd);
xen_map_identity_early(initial_kernel_pmd, max_pfn);
PFN_DOWN(__pa(initial_page_table)));
xen_write_cr3(__pa(initial_page_table));
- memblock_reserve(__pa(xen_start_info->pt_base),
- xen_start_info->nr_pt_frames * PAGE_SIZE);
+ memblock_reserve(xen_pt_base, xen_pt_size);
}
#endif /* CONFIG_X86_64 */
+void __init xen_reserve_special_pages(void)
+{
+ phys_addr_t paddr;
+
+ memblock_reserve(__pa(xen_start_info), PAGE_SIZE);
+ if (xen_start_info->store_mfn) {
+ paddr = PFN_PHYS(mfn_to_pfn(xen_start_info->store_mfn));
+ memblock_reserve(paddr, PAGE_SIZE);
+ }
+ if (!xen_initial_domain()) {
+ paddr = PFN_PHYS(mfn_to_pfn(xen_start_info->console.domU.mfn));
+ memblock_reserve(paddr, PAGE_SIZE);
+ }
+}
+
+void __init xen_pt_check_e820(void)
+{
+ if (xen_is_e820_reserved(xen_pt_base, xen_pt_size)) {
+ xen_raw_console_write("Xen hypervisor allocated page table memory conflicts with E820 map\n");
+ BUG();
+ }
+}
+
static unsigned char dummy_mapping[PAGE_SIZE] __page_aligned_bss;
static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
{
x86_init.paging.pagetable_init = xen_pagetable_init;
- /* Optimization - we can use the HVM one but it has no idea which
- * VCPUs are descheduled - which means that it will needlessly IPI
- * them. Xen knows so let it do the job.
- */
- if (xen_feature(XENFEAT_auto_translated_physmap)) {
- pv_mmu_ops.flush_tlb_others = xen_flush_tlb_others;
+ if (xen_feature(XENFEAT_auto_translated_physmap))
return;
- }
+
pv_mmu_ops = xen_mmu_ops;
memset(dummy_mapping, 0xff, PAGE_SIZE);
return 0;
}
-static int do_remap_mfn(struct vm_area_struct *vma,
+static int do_remap_gfn(struct vm_area_struct *vma,
unsigned long addr,
- xen_pfn_t *mfn, int nr,
+ xen_pfn_t *gfn, int nr,
int *err_ptr, pgprot_t prot,
unsigned domid,
struct page **pages)
if (xen_feature(XENFEAT_auto_translated_physmap)) {
#ifdef CONFIG_XEN_PVH
/* We need to update the local page tables and the xen HAP */
- return xen_xlate_remap_gfn_array(vma, addr, mfn, nr, err_ptr,
+ return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr,
prot, domid, pages);
#else
return -EINVAL;
#endif
}
- rmd.mfn = mfn;
+ rmd.mfn = gfn;
rmd.prot = prot;
/* We use the err_ptr to indicate if there we are doing a contigious
* mapping or a discontigious mapping. */
batch_left, &done, domid);
/*
- * @err_ptr may be the same buffer as @mfn, so
- * only clear it after each chunk of @mfn is
+ * @err_ptr may be the same buffer as @gfn, so
+ * only clear it after each chunk of @gfn is
* used.
*/
if (err_ptr) {
addr += range;
if (err_ptr)
err_ptr += batch;
+ cond_resched();
}
out:
return err < 0 ? err : mapped;
}
-int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
+int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
unsigned long addr,
- xen_pfn_t mfn, int nr,
+ xen_pfn_t gfn, int nr,
pgprot_t prot, unsigned domid,
struct page **pages)
{
- return do_remap_mfn(vma, addr, &mfn, nr, NULL, prot, domid, pages);
+ return do_remap_gfn(vma, addr, &gfn, nr, NULL, prot, domid, pages);
}
-EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
+EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
-int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
+int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
unsigned long addr,
- xen_pfn_t *mfn, int nr,
+ xen_pfn_t *gfn, int nr,
int *err_ptr, pgprot_t prot,
unsigned domid, struct page **pages)
{
* cause of "wrong memory was mapped in".
*/
BUG_ON(err_ptr == NULL);
- return do_remap_mfn(vma, addr, mfn, nr, err_ptr, prot, domid, pages);
+ return do_remap_gfn(vma, addr, gfn, nr, err_ptr, prot, domid, pages);
}
-EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
+EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
/* Returns: 0 success */
-int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
+int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
int numpgs, struct page **pages)
{
if (!pages || !xen_feature(XENFEAT_auto_translated_physmap))
return -EINVAL;
#endif
}
-EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
+EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
Code Review / kvmfornfv.git / blobdiff