1 // SPDX-License-Identifier: GPL-2.0
4 #include <linux/hugetlb.h>
5 #include <asm/pgalloc.h>
6 #include <asm/pgtable.h>
8 #include <asm/fixmap.h>
11 #ifdef CONFIG_DYNAMIC_PHYSICAL_MASK
12 phys_addr_t physical_mask __ro_after_init = (1ULL << __PHYSICAL_MASK_SHIFT) - 1;
13 EXPORT_SYMBOL(physical_mask);
17 #define PGTABLE_HIGHMEM __GFP_HIGHMEM
19 #define PGTABLE_HIGHMEM 0
22 gfp_t __userpte_alloc_gfp = GFP_PGTABLE_USER | PGTABLE_HIGHMEM;
24 pgtable_t pte_alloc_one(struct mm_struct *mm)
26 return __pte_alloc_one(mm, __userpte_alloc_gfp);
29 static int __init setup_userpte(char *arg)
35 * "userpte=nohigh" disables allocation of user pagetables in
38 if (strcmp(arg, "nohigh") == 0)
39 __userpte_alloc_gfp &= ~__GFP_HIGHMEM;
44 early_param("userpte", setup_userpte);
46 void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte)
48 pgtable_pte_page_dtor(pte);
49 paravirt_release_pte(page_to_pfn(pte));
50 paravirt_tlb_remove_table(tlb, pte);
53 #if CONFIG_PGTABLE_LEVELS > 2
54 void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd)
56 struct page *page = virt_to_page(pmd);
57 paravirt_release_pmd(__pa(pmd) >> PAGE_SHIFT);
59 * NOTE! For PAE, any changes to the top page-directory-pointer-table
60 * entries need a full cr3 reload to flush.
63 tlb->need_flush_all = 1;
65 pgtable_pmd_page_dtor(page);
66 paravirt_tlb_remove_table(tlb, page);
69 #if CONFIG_PGTABLE_LEVELS > 3
70 void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud)
72 paravirt_release_pud(__pa(pud) >> PAGE_SHIFT);
73 paravirt_tlb_remove_table(tlb, virt_to_page(pud));
76 #if CONFIG_PGTABLE_LEVELS > 4
77 void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d)
79 paravirt_release_p4d(__pa(p4d) >> PAGE_SHIFT);
80 paravirt_tlb_remove_table(tlb, virt_to_page(p4d));
82 #endif /* CONFIG_PGTABLE_LEVELS > 4 */
83 #endif /* CONFIG_PGTABLE_LEVELS > 3 */
84 #endif /* CONFIG_PGTABLE_LEVELS > 2 */
86 static inline void pgd_list_add(pgd_t *pgd)
88 struct page *page = virt_to_page(pgd);
90 list_add(&page->lru, &pgd_list);
93 static inline void pgd_list_del(pgd_t *pgd)
95 struct page *page = virt_to_page(pgd);
100 #define UNSHARED_PTRS_PER_PGD \
101 (SHARED_KERNEL_PMD ? KERNEL_PGD_BOUNDARY : PTRS_PER_PGD)
102 #define MAX_UNSHARED_PTRS_PER_PGD \
103 max_t(size_t, KERNEL_PGD_BOUNDARY, PTRS_PER_PGD)
106 static void pgd_set_mm(pgd_t *pgd, struct mm_struct *mm)
108 virt_to_page(pgd)->pt_mm = mm;
111 struct mm_struct *pgd_page_get_mm(struct page *page)
116 static void pgd_ctor(struct mm_struct *mm, pgd_t *pgd)
118 /* If the pgd points to a shared pagetable level (either the
119 ptes in non-PAE, or shared PMD in PAE), then just copy the
120 references from swapper_pg_dir. */
121 if (CONFIG_PGTABLE_LEVELS == 2 ||
122 (CONFIG_PGTABLE_LEVELS == 3 && SHARED_KERNEL_PMD) ||
123 CONFIG_PGTABLE_LEVELS >= 4) {
124 clone_pgd_range(pgd + KERNEL_PGD_BOUNDARY,
125 swapper_pg_dir + KERNEL_PGD_BOUNDARY,
129 /* list required to sync kernel mapping updates */
130 if (!SHARED_KERNEL_PMD) {
136 static void pgd_dtor(pgd_t *pgd)
138 if (SHARED_KERNEL_PMD)
141 spin_lock(&pgd_lock);
143 spin_unlock(&pgd_lock);
147 * List of all pgd's needed for non-PAE so it can invalidate entries
148 * in both cached and uncached pgd's; not needed for PAE since the
149 * kernel pmd is shared. If PAE were not to share the pmd a similar
150 * tactic would be needed. This is essentially codepath-based locking
151 * against pageattr.c; it is the unique case in which a valid change
152 * of kernel pagetables can't be lazily synchronized by vmalloc faults.
153 * vmalloc faults work because attached pagetables are never freed.
157 #ifdef CONFIG_X86_PAE
159 * In PAE mode, we need to do a cr3 reload (=tlb flush) when
160 * updating the top-level pagetable entries to guarantee the
161 * processor notices the update. Since this is expensive, and
162 * all 4 top-level entries are used almost immediately in a
163 * new process's life, we just pre-populate them here.
165 * Also, if we're in a paravirt environment where the kernel pmd is
166 * not shared between pagetables (!SHARED_KERNEL_PMDS), we allocate
167 * and initialize the kernel pmds here.
169 #define PREALLOCATED_PMDS UNSHARED_PTRS_PER_PGD
170 #define MAX_PREALLOCATED_PMDS MAX_UNSHARED_PTRS_PER_PGD
173 * We allocate separate PMDs for the kernel part of the user page-table
174 * when PTI is enabled. We need them to map the per-process LDT into the
175 * user-space page-table.
177 #define PREALLOCATED_USER_PMDS (boot_cpu_has(X86_FEATURE_PTI) ? \
179 #define MAX_PREALLOCATED_USER_PMDS KERNEL_PGD_PTRS
181 void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
183 paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
185 /* Note: almost everything apart from _PAGE_PRESENT is
186 reserved at the pmd (PDPT) level. */
187 set_pud(pudp, __pud(__pa(pmd) | _PAGE_PRESENT));
190 * According to Intel App note "TLBs, Paging-Structure Caches,
191 * and Their Invalidation", April 2007, document 317080-001,
192 * section 8.1: in PAE mode we explicitly have to flush the
193 * TLB via cr3 if the top-level pgd is changed...
197 #else /* !CONFIG_X86_PAE */
199 /* No need to prepopulate any pagetable entries in non-PAE modes. */
200 #define PREALLOCATED_PMDS 0
201 #define MAX_PREALLOCATED_PMDS 0
202 #define PREALLOCATED_USER_PMDS 0
203 #define MAX_PREALLOCATED_USER_PMDS 0
204 #endif /* CONFIG_X86_PAE */
206 static void free_pmds(struct mm_struct *mm, pmd_t *pmds[], int count)
210 for (i = 0; i < count; i++)
212 pgtable_pmd_page_dtor(virt_to_page(pmds[i]));
213 free_page((unsigned long)pmds[i]);
218 static int preallocate_pmds(struct mm_struct *mm, pmd_t *pmds[], int count)
222 gfp_t gfp = GFP_PGTABLE_USER;
225 gfp &= ~__GFP_ACCOUNT;
227 for (i = 0; i < count; i++) {
228 pmd_t *pmd = (pmd_t *)__get_free_page(gfp);
231 if (pmd && !pgtable_pmd_page_ctor(virt_to_page(pmd))) {
232 free_page((unsigned long)pmd);
242 free_pmds(mm, pmds, count);
250 * Mop up any pmd pages which may still be attached to the pgd.
251 * Normally they will be freed by munmap/exit_mmap, but any pmd we
252 * preallocate which never got a corresponding vma will need to be
255 static void mop_up_one_pmd(struct mm_struct *mm, pgd_t *pgdp)
259 if (pgd_val(pgd) != 0) {
260 pmd_t *pmd = (pmd_t *)pgd_page_vaddr(pgd);
264 paravirt_release_pmd(pgd_val(pgd) >> PAGE_SHIFT);
270 static void pgd_mop_up_pmds(struct mm_struct *mm, pgd_t *pgdp)
274 for (i = 0; i < PREALLOCATED_PMDS; i++)
275 mop_up_one_pmd(mm, &pgdp[i]);
277 #ifdef CONFIG_PAGE_TABLE_ISOLATION
279 if (!boot_cpu_has(X86_FEATURE_PTI))
282 pgdp = kernel_to_user_pgdp(pgdp);
284 for (i = 0; i < PREALLOCATED_USER_PMDS; i++)
285 mop_up_one_pmd(mm, &pgdp[i + KERNEL_PGD_BOUNDARY]);
289 static void pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmds[])
295 if (PREALLOCATED_PMDS == 0) /* Work around gcc-3.4.x bug */
298 p4d = p4d_offset(pgd, 0);
299 pud = pud_offset(p4d, 0);
301 for (i = 0; i < PREALLOCATED_PMDS; i++, pud++) {
302 pmd_t *pmd = pmds[i];
304 if (i >= KERNEL_PGD_BOUNDARY)
305 memcpy(pmd, (pmd_t *)pgd_page_vaddr(swapper_pg_dir[i]),
306 sizeof(pmd_t) * PTRS_PER_PMD);
308 pud_populate(mm, pud, pmd);
312 #ifdef CONFIG_PAGE_TABLE_ISOLATION
313 static void pgd_prepopulate_user_pmd(struct mm_struct *mm,
314 pgd_t *k_pgd, pmd_t *pmds[])
316 pgd_t *s_pgd = kernel_to_user_pgdp(swapper_pg_dir);
317 pgd_t *u_pgd = kernel_to_user_pgdp(k_pgd);
322 u_p4d = p4d_offset(u_pgd, 0);
323 u_pud = pud_offset(u_p4d, 0);
325 s_pgd += KERNEL_PGD_BOUNDARY;
326 u_pud += KERNEL_PGD_BOUNDARY;
328 for (i = 0; i < PREALLOCATED_USER_PMDS; i++, u_pud++, s_pgd++) {
329 pmd_t *pmd = pmds[i];
331 memcpy(pmd, (pmd_t *)pgd_page_vaddr(*s_pgd),
332 sizeof(pmd_t) * PTRS_PER_PMD);
334 pud_populate(mm, u_pud, pmd);
339 static void pgd_prepopulate_user_pmd(struct mm_struct *mm,
340 pgd_t *k_pgd, pmd_t *pmds[])
345 * Xen paravirt assumes pgd table should be in one page. 64 bit kernel also
346 * assumes that pgd should be in one page.
348 * But kernel with PAE paging that is not running as a Xen domain
349 * only needs to allocate 32 bytes for pgd instead of one page.
351 #ifdef CONFIG_X86_PAE
353 #include <linux/slab.h>
355 #define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
358 static struct kmem_cache *pgd_cache;
360 void __init pgtable_cache_init(void)
363 * When PAE kernel is running as a Xen domain, it does not use
364 * shared kernel pmd. And this requires a whole page for pgd.
366 if (!SHARED_KERNEL_PMD)
370 * when PAE kernel is not running as a Xen domain, it uses
371 * shared kernel pmd. Shared kernel pmd does not require a whole
372 * page for pgd. We are able to just allocate a 32-byte for pgd.
373 * During boot time, we create a 32-byte slab for pgd table allocation.
375 pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_ALIGN,
379 static inline pgd_t *_pgd_alloc(void)
382 * If no SHARED_KERNEL_PMD, PAE kernel is running as a Xen domain.
383 * We allocate one page for pgd.
385 if (!SHARED_KERNEL_PMD)
386 return (pgd_t *)__get_free_pages(GFP_PGTABLE_USER,
387 PGD_ALLOCATION_ORDER);
390 * Now PAE kernel is not running as a Xen domain. We can allocate
391 * a 32-byte slab for pgd to save memory space.
393 return kmem_cache_alloc(pgd_cache, GFP_PGTABLE_USER);
396 static inline void _pgd_free(pgd_t *pgd)
398 if (!SHARED_KERNEL_PMD)
399 free_pages((unsigned long)pgd, PGD_ALLOCATION_ORDER);
401 kmem_cache_free(pgd_cache, pgd);
405 static inline pgd_t *_pgd_alloc(void)
407 return (pgd_t *)__get_free_pages(GFP_PGTABLE_USER,
408 PGD_ALLOCATION_ORDER);
411 static inline void _pgd_free(pgd_t *pgd)
413 free_pages((unsigned long)pgd, PGD_ALLOCATION_ORDER);
415 #endif /* CONFIG_X86_PAE */
417 pgd_t *pgd_alloc(struct mm_struct *mm)
420 pmd_t *u_pmds[MAX_PREALLOCATED_USER_PMDS];
421 pmd_t *pmds[MAX_PREALLOCATED_PMDS];
430 if (preallocate_pmds(mm, pmds, PREALLOCATED_PMDS) != 0)
433 if (preallocate_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS) != 0)
436 if (paravirt_pgd_alloc(mm) != 0)
437 goto out_free_user_pmds;
440 * Make sure that pre-populating the pmds is atomic with
441 * respect to anything walking the pgd_list, so that they
442 * never see a partially populated pgd.
444 spin_lock(&pgd_lock);
447 pgd_prepopulate_pmd(mm, pgd, pmds);
448 pgd_prepopulate_user_pmd(mm, pgd, u_pmds);
450 spin_unlock(&pgd_lock);
455 free_pmds(mm, u_pmds, PREALLOCATED_USER_PMDS);
457 free_pmds(mm, pmds, PREALLOCATED_PMDS);
464 void pgd_free(struct mm_struct *mm, pgd_t *pgd)
466 pgd_mop_up_pmds(mm, pgd);
468 paravirt_pgd_free(mm, pgd);
473 * Used to set accessed or dirty bits in the page table entries
474 * on other architectures. On x86, the accessed and dirty bits
475 * are tracked by hardware. However, do_wp_page calls this function
476 * to also make the pte writeable at the same time the dirty bit is
477 * set. In that case we do actually need to write the PTE.
479 int ptep_set_access_flags(struct vm_area_struct *vma,
480 unsigned long address, pte_t *ptep,
481 pte_t entry, int dirty)
483 int changed = !pte_same(*ptep, entry);
485 if (changed && dirty)
486 set_pte(ptep, entry);
491 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
492 int pmdp_set_access_flags(struct vm_area_struct *vma,
493 unsigned long address, pmd_t *pmdp,
494 pmd_t entry, int dirty)
496 int changed = !pmd_same(*pmdp, entry);
498 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
500 if (changed && dirty) {
501 set_pmd(pmdp, entry);
503 * We had a write-protection fault here and changed the pmd
504 * to to more permissive. No need to flush the TLB for that,
505 * #PF is architecturally guaranteed to do that and in the
506 * worst-case we'll generate a spurious fault.
513 int pudp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
514 pud_t *pudp, pud_t entry, int dirty)
516 int changed = !pud_same(*pudp, entry);
518 VM_BUG_ON(address & ~HPAGE_PUD_MASK);
520 if (changed && dirty) {
521 set_pud(pudp, entry);
523 * We had a write-protection fault here and changed the pud
524 * to to more permissive. No need to flush the TLB for that,
525 * #PF is architecturally guaranteed to do that and in the
526 * worst-case we'll generate a spurious fault.
534 int ptep_test_and_clear_young(struct vm_area_struct *vma,
535 unsigned long addr, pte_t *ptep)
539 if (pte_young(*ptep))
540 ret = test_and_clear_bit(_PAGE_BIT_ACCESSED,
541 (unsigned long *) &ptep->pte);
546 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
547 int pmdp_test_and_clear_young(struct vm_area_struct *vma,
548 unsigned long addr, pmd_t *pmdp)
552 if (pmd_young(*pmdp))
553 ret = test_and_clear_bit(_PAGE_BIT_ACCESSED,
554 (unsigned long *)pmdp);
558 int pudp_test_and_clear_young(struct vm_area_struct *vma,
559 unsigned long addr, pud_t *pudp)
563 if (pud_young(*pudp))
564 ret = test_and_clear_bit(_PAGE_BIT_ACCESSED,
565 (unsigned long *)pudp);
571 int ptep_clear_flush_young(struct vm_area_struct *vma,
572 unsigned long address, pte_t *ptep)
575 * On x86 CPUs, clearing the accessed bit without a TLB flush
576 * doesn't cause data corruption. [ It could cause incorrect
577 * page aging and the (mistaken) reclaim of hot pages, but the
578 * chance of that should be relatively low. ]
580 * So as a performance optimization don't flush the TLB when
581 * clearing the accessed bit, it will eventually be flushed by
582 * a context switch or a VM operation anyway. [ In the rare
583 * event of it not getting flushed for a long time the delay
584 * shouldn't really matter because there's no real memory
585 * pressure for swapout to react to. ]
587 return ptep_test_and_clear_young(vma, address, ptep);
590 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
591 int pmdp_clear_flush_young(struct vm_area_struct *vma,
592 unsigned long address, pmd_t *pmdp)
596 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
598 young = pmdp_test_and_clear_young(vma, address, pmdp);
600 flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
607 * reserve_top_address - reserves a hole in the top of kernel address space
608 * @reserve - size of hole to reserve
610 * Can be used to relocate the fixmap area and poke a hole in the top
611 * of kernel address space to make room for a hypervisor.
613 void __init reserve_top_address(unsigned long reserve)
616 BUG_ON(fixmaps_set > 0);
617 __FIXADDR_TOP = round_down(-reserve, 1 << PMD_SHIFT) - PAGE_SIZE;
618 printk(KERN_INFO "Reserving virtual address space above 0x%08lx (rounded to 0x%08lx)\n",
619 -reserve, __FIXADDR_TOP + PAGE_SIZE);
625 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte)
627 unsigned long address = __fix_to_virt(idx);
631 * Ensure that the static initial page tables are covering the
634 BUILD_BUG_ON(__end_of_permanent_fixed_addresses >
635 (FIXMAP_PMD_NUM * PTRS_PER_PTE));
638 if (idx >= __end_of_fixed_addresses) {
642 set_pte_vaddr(address, pte);
646 void native_set_fixmap(unsigned /* enum fixed_addresses */ idx,
647 phys_addr_t phys, pgprot_t flags)
649 /* Sanitize 'prot' against any unsupported bits: */
650 pgprot_val(flags) &= __default_kernel_pte_mask;
652 __native_set_fixmap(idx, pfn_pte(phys >> PAGE_SHIFT, flags));
655 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
656 #ifdef CONFIG_X86_5LEVEL
658 * p4d_set_huge - setup kernel P4D mapping
660 * No 512GB pages yet -- always return 0
662 int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
668 * p4d_clear_huge - clear kernel P4D mapping when it is set
670 * No 512GB pages yet -- always return 0
672 int p4d_clear_huge(p4d_t *p4d)
679 * pud_set_huge - setup kernel PUD mapping
681 * MTRRs can override PAT memory types with 4KiB granularity. Therefore, this
682 * function sets up a huge page only if any of the following conditions are met:
684 * - MTRRs are disabled, or
686 * - MTRRs are enabled and the range is completely covered by a single MTRR, or
688 * - MTRRs are enabled and the corresponding MTRR memory type is WB, which
689 * has no effect on the requested PAT memory type.
691 * Callers should try to decrease page size (1GB -> 2MB -> 4K) if the bigger
692 * page mapping attempt fails.
694 * Returns 1 on success and 0 on failure.
696 int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot)
700 mtrr = mtrr_type_lookup(addr, addr + PUD_SIZE, &uniform);
701 if ((mtrr != MTRR_TYPE_INVALID) && (!uniform) &&
702 (mtrr != MTRR_TYPE_WRBACK))
705 /* Bail out if we are we on a populated non-leaf entry: */
706 if (pud_present(*pud) && !pud_huge(*pud))
709 prot = pgprot_4k_2_large(prot);
711 set_pte((pte_t *)pud, pfn_pte(
712 (u64)addr >> PAGE_SHIFT,
713 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
719 * pmd_set_huge - setup kernel PMD mapping
721 * See text over pud_set_huge() above.
723 * Returns 1 on success and 0 on failure.
725 int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
729 mtrr = mtrr_type_lookup(addr, addr + PMD_SIZE, &uniform);
730 if ((mtrr != MTRR_TYPE_INVALID) && (!uniform) &&
731 (mtrr != MTRR_TYPE_WRBACK)) {
732 pr_warn_once("%s: Cannot satisfy [mem %#010llx-%#010llx] with a huge-page mapping due to MTRR override.\n",
733 __func__, addr, addr + PMD_SIZE);
737 /* Bail out if we are we on a populated non-leaf entry: */
738 if (pmd_present(*pmd) && !pmd_huge(*pmd))
741 prot = pgprot_4k_2_large(prot);
743 set_pte((pte_t *)pmd, pfn_pte(
744 (u64)addr >> PAGE_SHIFT,
745 __pgprot(pgprot_val(prot) | _PAGE_PSE)));
751 * pud_clear_huge - clear kernel PUD mapping when it is set
753 * Returns 1 on success and 0 on failure (no PUD map is found).
755 int pud_clear_huge(pud_t *pud)
757 if (pud_large(*pud)) {
766 * pmd_clear_huge - clear kernel PMD mapping when it is set
768 * Returns 1 on success and 0 on failure (no PMD map is found).
770 int pmd_clear_huge(pmd_t *pmd)
772 if (pmd_large(*pmd)) {
781 * Until we support 512GB pages, skip them in the vmap area.
783 int p4d_free_pud_page(p4d_t *p4d, unsigned long addr)
790 * pud_free_pmd_page - Clear pud entry and free pmd page.
791 * @pud: Pointer to a PUD.
792 * @addr: Virtual address associated with pud.
794 * Context: The pud range has been unmapped and TLB purged.
795 * Return: 1 if clearing the entry succeeded. 0 otherwise.
797 * NOTE: Callers must allow a single page allocation.
799 int pud_free_pmd_page(pud_t *pud, unsigned long addr)
805 pmd = (pmd_t *)pud_page_vaddr(*pud);
806 pmd_sv = (pmd_t *)__get_free_page(GFP_KERNEL);
810 for (i = 0; i < PTRS_PER_PMD; i++) {
812 if (!pmd_none(pmd[i]))
818 /* INVLPG to clear all paging-structure caches */
819 flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1);
821 for (i = 0; i < PTRS_PER_PMD; i++) {
822 if (!pmd_none(pmd_sv[i])) {
823 pte = (pte_t *)pmd_page_vaddr(pmd_sv[i]);
824 free_page((unsigned long)pte);
828 free_page((unsigned long)pmd_sv);
830 pgtable_pmd_page_dtor(virt_to_page(pmd));
831 free_page((unsigned long)pmd);
837 * pmd_free_pte_page - Clear pmd entry and free pte page.
838 * @pmd: Pointer to a PMD.
839 * @addr: Virtual address associated with pmd.
841 * Context: The pmd range has been unmapped and TLB purged.
842 * Return: 1 if clearing the entry succeeded. 0 otherwise.
844 int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
848 pte = (pte_t *)pmd_page_vaddr(*pmd);
851 /* INVLPG to clear all paging-structure caches */
852 flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1);
854 free_page((unsigned long)pte);
859 #else /* !CONFIG_X86_64 */
861 int pud_free_pmd_page(pud_t *pud, unsigned long addr)
863 return pud_none(*pud);
867 * Disable free page handling on x86-PAE. This assures that ioremap()
868 * does not update sync'd pmd entries. See vmalloc_sync_one().
870 int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
872 return pmd_none(*pmd);
875 #endif /* CONFIG_X86_64 */
876 #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */