1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright 2002 Andi Kleen, SuSE Labs.
4 * Thanks to Ben LaHaise for precious feedback.
6 #include <linux/highmem.h>
7 #include <linux/memblock.h>
8 #include <linux/sched.h>
10 #include <linux/interrupt.h>
11 #include <linux/seq_file.h>
12 #include <linux/debugfs.h>
13 #include <linux/pfn.h>
14 #include <linux/percpu.h>
15 #include <linux/gfp.h>
16 #include <linux/pci.h>
17 #include <linux/vmalloc.h>
18 #include <linux/libnvdimm.h>
20 #include <asm/e820/api.h>
21 #include <asm/processor.h>
22 #include <asm/tlbflush.h>
23 #include <asm/sections.h>
24 #include <asm/setup.h>
25 #include <linux/uaccess.h>
26 #include <asm/pgalloc.h>
27 #include <asm/proto.h>
28 #include <asm/memtype.h>
29 #include <asm/set_memory.h>
31 #include "../mm_internal.h"
34 * The current flushing context - we pass it instead of 5 arguments:
41 unsigned long numpages;
42 unsigned long curpage;
45 unsigned int force_split : 1,
46 force_static_prot : 1;
56 static const int cpa_warn_level = CPA_PROTECT;
59 * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings)
60 * using cpa_lock. So that we don't allow any other cpu, with stale large tlb
61 * entries change the page attribute in parallel to some other cpu
62 * splitting a large page entry along with changing the attribute.
64 static DEFINE_SPINLOCK(cpa_lock);
66 #define CPA_FLUSHTLB 1
68 #define CPA_PAGES_ARRAY 4
69 #define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */
72 static unsigned long direct_pages_count[PG_LEVEL_NUM];
74 void update_page_count(int level, unsigned long pages)
76 /* Protect against CPA */
78 direct_pages_count[level] += pages;
79 spin_unlock(&pgd_lock);
82 static void split_page_count(int level)
84 if (direct_pages_count[level] == 0)
87 direct_pages_count[level]--;
88 direct_pages_count[level - 1] += PTRS_PER_PTE;
91 void arch_report_meminfo(struct seq_file *m)
93 seq_printf(m, "DirectMap4k: %8lu kB\n",
94 direct_pages_count[PG_LEVEL_4K] << 2);
95 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
96 seq_printf(m, "DirectMap2M: %8lu kB\n",
97 direct_pages_count[PG_LEVEL_2M] << 11);
99 seq_printf(m, "DirectMap4M: %8lu kB\n",
100 direct_pages_count[PG_LEVEL_2M] << 12);
103 seq_printf(m, "DirectMap1G: %8lu kB\n",
104 direct_pages_count[PG_LEVEL_1G] << 20);
107 static inline void split_page_count(int level) { }
110 #ifdef CONFIG_X86_CPA_STATISTICS
112 static unsigned long cpa_1g_checked;
113 static unsigned long cpa_1g_sameprot;
114 static unsigned long cpa_1g_preserved;
115 static unsigned long cpa_2m_checked;
116 static unsigned long cpa_2m_sameprot;
117 static unsigned long cpa_2m_preserved;
118 static unsigned long cpa_4k_install;
120 static inline void cpa_inc_1g_checked(void)
125 static inline void cpa_inc_2m_checked(void)
130 static inline void cpa_inc_4k_install(void)
135 static inline void cpa_inc_lp_sameprot(int level)
137 if (level == PG_LEVEL_1G)
143 static inline void cpa_inc_lp_preserved(int level)
145 if (level == PG_LEVEL_1G)
151 static int cpastats_show(struct seq_file *m, void *p)
153 seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked);
154 seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot);
155 seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved);
156 seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked);
157 seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot);
158 seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved);
159 seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install);
163 static int cpastats_open(struct inode *inode, struct file *file)
165 return single_open(file, cpastats_show, NULL);
168 static const struct file_operations cpastats_fops = {
169 .open = cpastats_open,
172 .release = single_release,
175 static int __init cpa_stats_init(void)
177 debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL,
181 late_initcall(cpa_stats_init);
183 static inline void cpa_inc_1g_checked(void) { }
184 static inline void cpa_inc_2m_checked(void) { }
185 static inline void cpa_inc_4k_install(void) { }
186 static inline void cpa_inc_lp_sameprot(int level) { }
187 static inline void cpa_inc_lp_preserved(int level) { }
192 within(unsigned long addr, unsigned long start, unsigned long end)
194 return addr >= start && addr < end;
198 within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
200 return addr >= start && addr <= end;
205 static inline unsigned long highmap_start_pfn(void)
207 return __pa_symbol(_text) >> PAGE_SHIFT;
210 static inline unsigned long highmap_end_pfn(void)
212 /* Do not reference physical address outside the kernel. */
213 return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT;
216 static bool __cpa_pfn_in_highmap(unsigned long pfn)
219 * Kernel text has an alias mapping at a high address, known
222 return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn());
227 static bool __cpa_pfn_in_highmap(unsigned long pfn)
229 /* There is no highmap on 32-bit */
236 * See set_mce_nospec().
238 * Machine check recovery code needs to change cache mode of poisoned pages to
239 * UC to avoid speculative access logging another error. But passing the
240 * address of the 1:1 mapping to set_memory_uc() is a fine way to encourage a
241 * speculative access. So we cheat and flip the top bit of the address. This
242 * works fine for the code that updates the page tables. But at the end of the
243 * process we need to flush the TLB and cache and the non-canonical address
244 * causes a #GP fault when used by the INVLPG and CLFLUSH instructions.
246 * But in the common case we already have a canonical address. This code
247 * will fix the top bit if needed and is a no-op otherwise.
249 static inline unsigned long fix_addr(unsigned long addr)
252 return (long)(addr << 1) >> 1;
258 static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx)
260 if (cpa->flags & CPA_PAGES_ARRAY) {
261 struct page *page = cpa->pages[idx];
263 if (unlikely(PageHighMem(page)))
266 return (unsigned long)page_address(page);
269 if (cpa->flags & CPA_ARRAY)
270 return cpa->vaddr[idx];
272 return *cpa->vaddr + idx * PAGE_SIZE;
279 static void clflush_cache_range_opt(void *vaddr, unsigned int size)
281 const unsigned long clflush_size = boot_cpu_data.x86_clflush_size;
282 void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1));
283 void *vend = vaddr + size;
288 for (; p < vend; p += clflush_size)
293 * clflush_cache_range - flush a cache range with clflush
294 * @vaddr: virtual start address
295 * @size: number of bytes to flush
297 * CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or
298 * SFENCE to avoid ordering issues.
300 void clflush_cache_range(void *vaddr, unsigned int size)
303 clflush_cache_range_opt(vaddr, size);
306 EXPORT_SYMBOL_GPL(clflush_cache_range);
308 #ifdef CONFIG_ARCH_HAS_PMEM_API
309 void arch_invalidate_pmem(void *addr, size_t size)
311 clflush_cache_range(addr, size);
313 EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
316 static void __cpa_flush_all(void *arg)
318 unsigned long cache = (unsigned long)arg;
321 * Flush all to work around Errata in early athlons regarding
322 * large page flushing.
326 if (cache && boot_cpu_data.x86 >= 4)
330 static void cpa_flush_all(unsigned long cache)
332 BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
334 on_each_cpu(__cpa_flush_all, (void *) cache, 1);
337 static void __cpa_flush_tlb(void *data)
339 struct cpa_data *cpa = data;
342 for (i = 0; i < cpa->numpages; i++)
343 __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
346 static void cpa_flush(struct cpa_data *data, int cache)
348 struct cpa_data *cpa = data;
351 BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
353 if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
354 cpa_flush_all(cache);
358 if (cpa->numpages <= tlb_single_page_flush_ceiling)
359 on_each_cpu(__cpa_flush_tlb, cpa, 1);
367 for (i = 0; i < cpa->numpages; i++) {
368 unsigned long addr = __cpa_addr(cpa, i);
371 pte_t *pte = lookup_address(addr, &level);
374 * Only flush present addresses:
376 if (pte && (pte_val(*pte) & _PAGE_PRESENT))
377 clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE);
382 static bool overlaps(unsigned long r1_start, unsigned long r1_end,
383 unsigned long r2_start, unsigned long r2_end)
385 return (r1_start <= r2_end && r1_end >= r2_start) ||
386 (r2_start <= r1_end && r2_end >= r1_start);
389 #ifdef CONFIG_PCI_BIOS
391 * The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS
392 * based config access (CONFIG_PCI_GOBIOS) support.
394 #define BIOS_PFN PFN_DOWN(BIOS_BEGIN)
395 #define BIOS_PFN_END PFN_DOWN(BIOS_END - 1)
397 static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
399 if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END))
404 static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
411 * The .rodata section needs to be read-only. Using the pfn catches all
412 * aliases. This also includes __ro_after_init, so do not enforce until
413 * kernel_set_to_readonly is true.
415 static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn)
417 unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata));
420 * Note: __end_rodata is at page aligned and not inclusive, so
421 * subtract 1 to get the last enforced PFN in the rodata area.
423 epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1;
425 if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro))
431 * Protect kernel text against becoming non executable by forbidding
432 * _PAGE_NX. This protects only the high kernel mapping (_text -> _etext)
433 * out of which the kernel actually executes. Do not protect the low
436 * This does not cover __inittext since that is gone after boot.
438 static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end)
440 unsigned long t_end = (unsigned long)_etext - 1;
441 unsigned long t_start = (unsigned long)_text;
443 if (overlaps(start, end, t_start, t_end))
448 #if defined(CONFIG_X86_64)
450 * Once the kernel maps the text as RO (kernel_set_to_readonly is set),
451 * kernel text mappings for the large page aligned text, rodata sections
452 * will be always read-only. For the kernel identity mappings covering the
453 * holes caused by this alignment can be anything that user asks.
455 * This will preserve the large page mappings for kernel text/data at no
458 static pgprotval_t protect_kernel_text_ro(unsigned long start,
461 unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1;
462 unsigned long t_start = (unsigned long)_text;
465 if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end))
468 * Don't enforce the !RW mapping for the kernel text mapping, if
469 * the current mapping is already using small page mapping. No
470 * need to work hard to preserve large page mappings in this case.
472 * This also fixes the Linux Xen paravirt guest boot failure caused
473 * by unexpected read-only mappings for kernel identity
474 * mappings. In this paravirt guest case, the kernel text mapping
475 * and the kernel identity mapping share the same page-table pages,
476 * so the protections for kernel text and identity mappings have to
479 if (lookup_address(start, &level) && (level != PG_LEVEL_4K))
484 static pgprotval_t protect_kernel_text_ro(unsigned long start,
491 static inline bool conflicts(pgprot_t prot, pgprotval_t val)
493 return (pgprot_val(prot) & ~val) != pgprot_val(prot);
496 static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val,
497 unsigned long start, unsigned long end,
498 unsigned long pfn, const char *txt)
500 static const char *lvltxt[] = {
501 [CPA_CONFLICT] = "conflict",
502 [CPA_PROTECT] = "protect",
503 [CPA_DETECT] = "detect",
506 if (warnlvl > cpa_warn_level || !conflicts(prot, val))
509 pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n",
510 lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot),
511 (unsigned long long)val);
515 * Certain areas of memory on x86 require very specific protection flags,
516 * for example the BIOS area or kernel text. Callers don't always get this
517 * right (again, ioremap() on BIOS memory is not uncommon) so this function
518 * checks and fixes these known static required protection bits.
520 static inline pgprot_t static_protections(pgprot_t prot, unsigned long start,
521 unsigned long pfn, unsigned long npg,
522 unsigned long lpsize, int warnlvl)
524 pgprotval_t forbidden, res;
528 * There is no point in checking RW/NX conflicts when the requested
529 * mapping is setting the page !PRESENT.
531 if (!(pgprot_val(prot) & _PAGE_PRESENT))
534 /* Operate on the virtual address */
535 end = start + npg * PAGE_SIZE - 1;
537 res = protect_kernel_text(start, end);
538 check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX");
542 * Special case to preserve a large page. If the change spawns the
543 * full large page mapping then there is no point to split it
544 * up. Happens with ftrace and is going to be removed once ftrace
545 * switched to text_poke().
547 if (lpsize != (npg * PAGE_SIZE) || (start & (lpsize - 1))) {
548 res = protect_kernel_text_ro(start, end);
549 check_conflict(warnlvl, prot, res, start, end, pfn, "Text RO");
553 /* Check the PFN directly */
554 res = protect_pci_bios(pfn, pfn + npg - 1);
555 check_conflict(warnlvl, prot, res, start, end, pfn, "PCIBIOS NX");
558 res = protect_rodata(pfn, pfn + npg - 1);
559 check_conflict(warnlvl, prot, res, start, end, pfn, "Rodata RO");
562 return __pgprot(pgprot_val(prot) & ~forbidden);
566 * Lookup the page table entry for a virtual address in a specific pgd.
567 * Return a pointer to the entry and the level of the mapping.
569 pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
576 *level = PG_LEVEL_NONE;
581 p4d = p4d_offset(pgd, address);
585 *level = PG_LEVEL_512G;
586 if (p4d_large(*p4d) || !p4d_present(*p4d))
589 pud = pud_offset(p4d, address);
593 *level = PG_LEVEL_1G;
594 if (pud_large(*pud) || !pud_present(*pud))
597 pmd = pmd_offset(pud, address);
601 *level = PG_LEVEL_2M;
602 if (pmd_large(*pmd) || !pmd_present(*pmd))
605 *level = PG_LEVEL_4K;
607 return pte_offset_kernel(pmd, address);
611 * Lookup the page table entry for a virtual address. Return a pointer
612 * to the entry and the level of the mapping.
614 * Note: We return pud and pmd either when the entry is marked large
615 * or when the present bit is not set. Otherwise we would return a
616 * pointer to a nonexisting mapping.
618 pte_t *lookup_address(unsigned long address, unsigned int *level)
620 return lookup_address_in_pgd(pgd_offset_k(address), address, level);
622 EXPORT_SYMBOL_GPL(lookup_address);
625 * Lookup the page table entry for a virtual address in a given mm. Return a
626 * pointer to the entry and the level of the mapping.
628 pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address,
631 return lookup_address_in_pgd(pgd_offset(mm, address), address, level);
633 EXPORT_SYMBOL_GPL(lookup_address_in_mm);
635 static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
639 return lookup_address_in_pgd(cpa->pgd + pgd_index(address),
642 return lookup_address(address, level);
646 * Lookup the PMD entry for a virtual address. Return a pointer to the entry
647 * or NULL if not present.
649 pmd_t *lookup_pmd_address(unsigned long address)
655 pgd = pgd_offset_k(address);
659 p4d = p4d_offset(pgd, address);
660 if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d))
663 pud = pud_offset(p4d, address);
664 if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud))
667 return pmd_offset(pud, address);
671 * This is necessary because __pa() does not work on some
672 * kinds of memory, like vmalloc() or the alloc_remap()
673 * areas on 32-bit NUMA systems. The percpu areas can
674 * end up in this kind of memory, for instance.
676 * This could be optimized, but it is only intended to be
677 * used at inititalization time, and keeping it
678 * unoptimized should increase the testing coverage for
679 * the more obscure platforms.
681 phys_addr_t slow_virt_to_phys(void *__virt_addr)
683 unsigned long virt_addr = (unsigned long)__virt_addr;
684 phys_addr_t phys_addr;
685 unsigned long offset;
689 pte = lookup_address(virt_addr, &level);
693 * pXX_pfn() returns unsigned long, which must be cast to phys_addr_t
694 * before being left-shifted PAGE_SHIFT bits -- this trick is to
695 * make 32-PAE kernel work correctly.
699 phys_addr = (phys_addr_t)pud_pfn(*(pud_t *)pte) << PAGE_SHIFT;
700 offset = virt_addr & ~PUD_PAGE_MASK;
703 phys_addr = (phys_addr_t)pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT;
704 offset = virt_addr & ~PMD_PAGE_MASK;
707 phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
708 offset = virt_addr & ~PAGE_MASK;
711 return (phys_addr_t)(phys_addr | offset);
713 EXPORT_SYMBOL_GPL(slow_virt_to_phys);
716 * Set the new pmd in all the pgds we know about:
718 static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
721 set_pte_atomic(kpte, pte);
723 if (!SHARED_KERNEL_PMD) {
726 list_for_each_entry(page, &pgd_list, lru) {
732 pgd = (pgd_t *)page_address(page) + pgd_index(address);
733 p4d = p4d_offset(pgd, address);
734 pud = pud_offset(p4d, address);
735 pmd = pmd_offset(pud, address);
736 set_pte_atomic((pte_t *)pmd, pte);
742 static pgprot_t pgprot_clear_protnone_bits(pgprot_t prot)
745 * _PAGE_GLOBAL means "global page" for present PTEs.
746 * But, it is also used to indicate _PAGE_PROTNONE
747 * for non-present PTEs.
749 * This ensures that a _PAGE_GLOBAL PTE going from
750 * present to non-present is not confused as
753 if (!(pgprot_val(prot) & _PAGE_PRESENT))
754 pgprot_val(prot) &= ~_PAGE_GLOBAL;
759 static int __should_split_large_page(pte_t *kpte, unsigned long address,
760 struct cpa_data *cpa)
762 unsigned long numpages, pmask, psize, lpaddr, pfn, old_pfn;
763 pgprot_t old_prot, new_prot, req_prot, chk_prot;
768 * Check for races, another CPU might have split this page
771 tmp = _lookup_address_cpa(cpa, address, &level);
777 old_prot = pmd_pgprot(*(pmd_t *)kpte);
778 old_pfn = pmd_pfn(*(pmd_t *)kpte);
779 cpa_inc_2m_checked();
782 old_prot = pud_pgprot(*(pud_t *)kpte);
783 old_pfn = pud_pfn(*(pud_t *)kpte);
784 cpa_inc_1g_checked();
790 psize = page_level_size(level);
791 pmask = page_level_mask(level);
794 * Calculate the number of pages, which fit into this large
795 * page starting at address:
797 lpaddr = (address + psize) & pmask;
798 numpages = (lpaddr - address) >> PAGE_SHIFT;
799 if (numpages < cpa->numpages)
800 cpa->numpages = numpages;
803 * We are safe now. Check whether the new pgprot is the same:
804 * Convert protection attributes to 4k-format, as cpa->mask* are set
808 /* Clear PSE (aka _PAGE_PAT) and move PAT bit to correct position */
809 req_prot = pgprot_large_2_4k(old_prot);
811 pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr);
812 pgprot_val(req_prot) |= pgprot_val(cpa->mask_set);
815 * req_prot is in format of 4k pages. It must be converted to large
816 * page format: the caching mode includes the PAT bit located at
817 * different bit positions in the two formats.
819 req_prot = pgprot_4k_2_large(req_prot);
820 req_prot = pgprot_clear_protnone_bits(req_prot);
821 if (pgprot_val(req_prot) & _PAGE_PRESENT)
822 pgprot_val(req_prot) |= _PAGE_PSE;
825 * old_pfn points to the large page base pfn. So we need to add the
826 * offset of the virtual address:
828 pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT);
832 * Calculate the large page base address and the number of 4K pages
835 lpaddr = address & pmask;
836 numpages = psize >> PAGE_SHIFT;
839 * Sanity check that the existing mapping is correct versus the static
840 * protections. static_protections() guards against !PRESENT, so no
841 * extra conditional required here.
843 chk_prot = static_protections(old_prot, lpaddr, old_pfn, numpages,
844 psize, CPA_CONFLICT);
846 if (WARN_ON_ONCE(pgprot_val(chk_prot) != pgprot_val(old_prot))) {
848 * Split the large page and tell the split code to
849 * enforce static protections.
851 cpa->force_static_prot = 1;
856 * Optimization: If the requested pgprot is the same as the current
857 * pgprot, then the large page can be preserved and no updates are
858 * required independent of alignment and length of the requested
859 * range. The above already established that the current pgprot is
860 * correct, which in consequence makes the requested pgprot correct
861 * as well if it is the same. The static protection scan below will
862 * not come to a different conclusion.
864 if (pgprot_val(req_prot) == pgprot_val(old_prot)) {
865 cpa_inc_lp_sameprot(level);
870 * If the requested range does not cover the full page, split it up
872 if (address != lpaddr || cpa->numpages != numpages)
876 * Check whether the requested pgprot is conflicting with a static
877 * protection requirement in the large page.
879 new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages,
883 * If there is a conflict, split the large page.
885 * There used to be a 4k wise evaluation trying really hard to
886 * preserve the large pages, but experimentation has shown, that this
887 * does not help at all. There might be corner cases which would
888 * preserve one large page occasionally, but it's really not worth the
889 * extra code and cycles for the common case.
891 if (pgprot_val(req_prot) != pgprot_val(new_prot))
894 /* All checks passed. Update the large page mapping. */
895 new_pte = pfn_pte(old_pfn, new_prot);
896 __set_pmd_pte(kpte, address, new_pte);
897 cpa->flags |= CPA_FLUSHTLB;
898 cpa_inc_lp_preserved(level);
902 static int should_split_large_page(pte_t *kpte, unsigned long address,
903 struct cpa_data *cpa)
907 if (cpa->force_split)
910 spin_lock(&pgd_lock);
911 do_split = __should_split_large_page(kpte, address, cpa);
912 spin_unlock(&pgd_lock);
917 static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn,
918 pgprot_t ref_prot, unsigned long address,
921 unsigned int npg = PFN_DOWN(size);
925 * If should_split_large_page() discovered an inconsistent mapping,
926 * remove the invalid protection in the split mapping.
928 if (!cpa->force_static_prot)
931 /* Hand in lpsize = 0 to enforce the protection mechanism */
932 prot = static_protections(ref_prot, address, pfn, npg, 0, CPA_PROTECT);
934 if (pgprot_val(prot) == pgprot_val(ref_prot))
938 * If this is splitting a PMD, fix it up. PUD splits cannot be
939 * fixed trivially as that would require to rescan the newly
940 * installed PMD mappings after returning from split_large_page()
941 * so an eventual further split can allocate the necessary PTE
942 * pages. Warn for now and revisit it in case this actually
945 if (size == PAGE_SIZE)
948 pr_warn_once("CPA: Cannot fixup static protections for PUD split\n");
950 set_pte(pte, pfn_pte(pfn, ref_prot));
954 __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
957 unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1;
958 pte_t *pbase = (pte_t *)page_address(base);
959 unsigned int i, level;
963 spin_lock(&pgd_lock);
965 * Check for races, another CPU might have split this page
968 tmp = _lookup_address_cpa(cpa, address, &level);
970 spin_unlock(&pgd_lock);
974 paravirt_alloc_pte(&init_mm, page_to_pfn(base));
978 ref_prot = pmd_pgprot(*(pmd_t *)kpte);
980 * Clear PSE (aka _PAGE_PAT) and move
981 * PAT bit to correct position.
983 ref_prot = pgprot_large_2_4k(ref_prot);
984 ref_pfn = pmd_pfn(*(pmd_t *)kpte);
985 lpaddr = address & PMD_MASK;
990 ref_prot = pud_pgprot(*(pud_t *)kpte);
991 ref_pfn = pud_pfn(*(pud_t *)kpte);
992 pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT;
993 lpaddr = address & PUD_MASK;
996 * Clear the PSE flags if the PRESENT flag is not set
997 * otherwise pmd_present/pmd_huge will return true
998 * even on a non present pmd.
1000 if (!(pgprot_val(ref_prot) & _PAGE_PRESENT))
1001 pgprot_val(ref_prot) &= ~_PAGE_PSE;
1005 spin_unlock(&pgd_lock);
1009 ref_prot = pgprot_clear_protnone_bits(ref_prot);
1012 * Get the target pfn from the original entry:
1015 for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc, lpaddr += lpinc)
1016 split_set_pte(cpa, pbase + i, pfn, ref_prot, lpaddr, lpinc);
1018 if (virt_addr_valid(address)) {
1019 unsigned long pfn = PFN_DOWN(__pa(address));
1021 if (pfn_range_is_mapped(pfn, pfn + 1))
1022 split_page_count(level);
1026 * Install the new, split up pagetable.
1028 * We use the standard kernel pagetable protections for the new
1029 * pagetable protections, the actual ptes set above control the
1030 * primary protection behavior:
1032 __set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE)));
1035 * Do a global flush tlb after splitting the large page
1036 * and before we do the actual change page attribute in the PTE.
1038 * Without this, we violate the TLB application note, that says:
1039 * "The TLBs may contain both ordinary and large-page
1040 * translations for a 4-KByte range of linear addresses. This
1041 * may occur if software modifies the paging structures so that
1042 * the page size used for the address range changes. If the two
1043 * translations differ with respect to page frame or attributes
1044 * (e.g., permissions), processor behavior is undefined and may
1045 * be implementation-specific."
1047 * We do this global tlb flush inside the cpa_lock, so that we
1048 * don't allow any other cpu, with stale tlb entries change the
1049 * page attribute in parallel, that also falls into the
1050 * just split large page entry.
1053 spin_unlock(&pgd_lock);
1058 static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
1059 unsigned long address)
1063 if (!debug_pagealloc_enabled())
1064 spin_unlock(&cpa_lock);
1065 base = alloc_pages(GFP_KERNEL, 0);
1066 if (!debug_pagealloc_enabled())
1067 spin_lock(&cpa_lock);
1071 if (__split_large_page(cpa, kpte, address, base))
1077 static bool try_to_free_pte_page(pte_t *pte)
1081 for (i = 0; i < PTRS_PER_PTE; i++)
1082 if (!pte_none(pte[i]))
1085 free_page((unsigned long)pte);
1089 static bool try_to_free_pmd_page(pmd_t *pmd)
1093 for (i = 0; i < PTRS_PER_PMD; i++)
1094 if (!pmd_none(pmd[i]))
1097 free_page((unsigned long)pmd);
1101 static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
1103 pte_t *pte = pte_offset_kernel(pmd, start);
1105 while (start < end) {
1106 set_pte(pte, __pte(0));
1112 if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
1119 static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd,
1120 unsigned long start, unsigned long end)
1122 if (unmap_pte_range(pmd, start, end))
1123 if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
1127 static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
1129 pmd_t *pmd = pmd_offset(pud, start);
1132 * Not on a 2MB page boundary?
1134 if (start & (PMD_SIZE - 1)) {
1135 unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
1136 unsigned long pre_end = min_t(unsigned long, end, next_page);
1138 __unmap_pmd_range(pud, pmd, start, pre_end);
1145 * Try to unmap in 2M chunks.
1147 while (end - start >= PMD_SIZE) {
1148 if (pmd_large(*pmd))
1151 __unmap_pmd_range(pud, pmd, start, start + PMD_SIZE);
1161 return __unmap_pmd_range(pud, pmd, start, end);
1164 * Try again to free the PMD page if haven't succeeded above.
1166 if (!pud_none(*pud))
1167 if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
1171 static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end)
1173 pud_t *pud = pud_offset(p4d, start);
1176 * Not on a GB page boundary?
1178 if (start & (PUD_SIZE - 1)) {
1179 unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
1180 unsigned long pre_end = min_t(unsigned long, end, next_page);
1182 unmap_pmd_range(pud, start, pre_end);
1189 * Try to unmap in 1G chunks?
1191 while (end - start >= PUD_SIZE) {
1193 if (pud_large(*pud))
1196 unmap_pmd_range(pud, start, start + PUD_SIZE);
1206 unmap_pmd_range(pud, start, end);
1209 * No need to try to free the PUD page because we'll free it in
1210 * populate_pgd's error path
1214 static int alloc_pte_page(pmd_t *pmd)
1216 pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
1220 set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
1224 static int alloc_pmd_page(pud_t *pud)
1226 pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
1230 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
1234 static void populate_pte(struct cpa_data *cpa,
1235 unsigned long start, unsigned long end,
1236 unsigned num_pages, pmd_t *pmd, pgprot_t pgprot)
1240 pte = pte_offset_kernel(pmd, start);
1242 pgprot = pgprot_clear_protnone_bits(pgprot);
1244 while (num_pages-- && start < end) {
1245 set_pte(pte, pfn_pte(cpa->pfn, pgprot));
1253 static long populate_pmd(struct cpa_data *cpa,
1254 unsigned long start, unsigned long end,
1255 unsigned num_pages, pud_t *pud, pgprot_t pgprot)
1259 pgprot_t pmd_pgprot;
1262 * Not on a 2M boundary?
1264 if (start & (PMD_SIZE - 1)) {
1265 unsigned long pre_end = start + (num_pages << PAGE_SHIFT);
1266 unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
1268 pre_end = min_t(unsigned long, pre_end, next_page);
1269 cur_pages = (pre_end - start) >> PAGE_SHIFT;
1270 cur_pages = min_t(unsigned int, num_pages, cur_pages);
1275 pmd = pmd_offset(pud, start);
1277 if (alloc_pte_page(pmd))
1280 populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
1286 * We mapped them all?
1288 if (num_pages == cur_pages)
1291 pmd_pgprot = pgprot_4k_2_large(pgprot);
1293 while (end - start >= PMD_SIZE) {
1296 * We cannot use a 1G page so allocate a PMD page if needed.
1299 if (alloc_pmd_page(pud))
1302 pmd = pmd_offset(pud, start);
1304 set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn,
1305 canon_pgprot(pmd_pgprot))));
1308 cpa->pfn += PMD_SIZE >> PAGE_SHIFT;
1309 cur_pages += PMD_SIZE >> PAGE_SHIFT;
1313 * Map trailing 4K pages.
1316 pmd = pmd_offset(pud, start);
1318 if (alloc_pte_page(pmd))
1321 populate_pte(cpa, start, end, num_pages - cur_pages,
1327 static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d,
1333 pgprot_t pud_pgprot;
1335 end = start + (cpa->numpages << PAGE_SHIFT);
1338 * Not on a Gb page boundary? => map everything up to it with
1341 if (start & (PUD_SIZE - 1)) {
1342 unsigned long pre_end;
1343 unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
1345 pre_end = min_t(unsigned long, end, next_page);
1346 cur_pages = (pre_end - start) >> PAGE_SHIFT;
1347 cur_pages = min_t(int, (int)cpa->numpages, cur_pages);
1349 pud = pud_offset(p4d, start);
1355 if (alloc_pmd_page(pud))
1358 cur_pages = populate_pmd(cpa, start, pre_end, cur_pages,
1366 /* We mapped them all? */
1367 if (cpa->numpages == cur_pages)
1370 pud = pud_offset(p4d, start);
1371 pud_pgprot = pgprot_4k_2_large(pgprot);
1374 * Map everything starting from the Gb boundary, possibly with 1G pages
1376 while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) {
1377 set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
1378 canon_pgprot(pud_pgprot))));
1381 cpa->pfn += PUD_SIZE >> PAGE_SHIFT;
1382 cur_pages += PUD_SIZE >> PAGE_SHIFT;
1386 /* Map trailing leftover */
1390 pud = pud_offset(p4d, start);
1392 if (alloc_pmd_page(pud))
1395 tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages,
1406 * Restrictions for kernel page table do not necessarily apply when mapping in
1409 static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
1411 pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
1412 pud_t *pud = NULL; /* shut up gcc */
1417 pgd_entry = cpa->pgd + pgd_index(addr);
1419 if (pgd_none(*pgd_entry)) {
1420 p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL);
1424 set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE));
1428 * Allocate a PUD page and hand it down for mapping.
1430 p4d = p4d_offset(pgd_entry, addr);
1431 if (p4d_none(*p4d)) {
1432 pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
1436 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE));
1439 pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr);
1440 pgprot_val(pgprot) |= pgprot_val(cpa->mask_set);
1442 ret = populate_pud(cpa, addr, p4d, pgprot);
1445 * Leave the PUD page in place in case some other CPU or thread
1446 * already found it, but remove any useless entries we just
1449 unmap_pud_range(p4d, addr,
1450 addr + (cpa->numpages << PAGE_SHIFT));
1454 cpa->numpages = ret;
1458 static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
1463 * Right now, we only execute this code path when mapping
1464 * the EFI virtual memory map regions, no other users
1465 * provide a ->pgd value. This may change in the future.
1467 return populate_pgd(cpa, vaddr);
1471 * Ignore all non primary paths.
1479 * Ignore the NULL PTE for kernel identity mapping, as it is expected
1481 * Also set numpages to '1' indicating that we processed cpa req for
1482 * one virtual address page and its pfn. TBD: numpages can be set based
1483 * on the initial value and the level returned by lookup_address().
1485 if (within(vaddr, PAGE_OFFSET,
1486 PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) {
1488 cpa->pfn = __pa(vaddr) >> PAGE_SHIFT;
1491 } else if (__cpa_pfn_in_highmap(cpa->pfn)) {
1492 /* Faults in the highmap are OK, so do not warn: */
1495 WARN(1, KERN_WARNING "CPA: called for zero pte. "
1496 "vaddr = %lx cpa->vaddr = %lx\n", vaddr,
1503 static int __change_page_attr(struct cpa_data *cpa, int primary)
1505 unsigned long address;
1508 pte_t *kpte, old_pte;
1510 address = __cpa_addr(cpa, cpa->curpage);
1512 kpte = _lookup_address_cpa(cpa, address, &level);
1514 return __cpa_process_fault(cpa, address, primary);
1517 if (pte_none(old_pte))
1518 return __cpa_process_fault(cpa, address, primary);
1520 if (level == PG_LEVEL_4K) {
1522 pgprot_t new_prot = pte_pgprot(old_pte);
1523 unsigned long pfn = pte_pfn(old_pte);
1525 pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
1526 pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
1528 cpa_inc_4k_install();
1529 /* Hand in lpsize = 0 to enforce the protection mechanism */
1530 new_prot = static_protections(new_prot, address, pfn, 1, 0,
1533 new_prot = pgprot_clear_protnone_bits(new_prot);
1536 * We need to keep the pfn from the existing PTE,
1537 * after all we're only going to change it's attributes
1538 * not the memory it points to
1540 new_pte = pfn_pte(pfn, new_prot);
1543 * Do we really change anything ?
1545 if (pte_val(old_pte) != pte_val(new_pte)) {
1546 set_pte_atomic(kpte, new_pte);
1547 cpa->flags |= CPA_FLUSHTLB;
1554 * Check, whether we can keep the large page intact
1555 * and just change the pte:
1557 do_split = should_split_large_page(kpte, address, cpa);
1559 * When the range fits into the existing large page,
1560 * return. cp->numpages and cpa->tlbflush have been updated in
1567 * We have to split the large page:
1569 err = split_large_page(cpa, kpte, address);
1576 static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias);
1578 static int cpa_process_alias(struct cpa_data *cpa)
1580 struct cpa_data alias_cpa;
1581 unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT);
1582 unsigned long vaddr;
1585 if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1))
1589 * No need to redo, when the primary call touched the direct
1592 vaddr = __cpa_addr(cpa, cpa->curpage);
1593 if (!(within(vaddr, PAGE_OFFSET,
1594 PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) {
1597 alias_cpa.vaddr = &laddr;
1598 alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
1599 alias_cpa.curpage = 0;
1601 ret = __change_page_attr_set_clr(&alias_cpa, 0);
1606 #ifdef CONFIG_X86_64
1608 * If the primary call didn't touch the high mapping already
1609 * and the physical address is inside the kernel map, we need
1610 * to touch the high mapped kernel as well:
1612 if (!within(vaddr, (unsigned long)_text, _brk_end) &&
1613 __cpa_pfn_in_highmap(cpa->pfn)) {
1614 unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) +
1615 __START_KERNEL_map - phys_base;
1617 alias_cpa.vaddr = &temp_cpa_vaddr;
1618 alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
1619 alias_cpa.curpage = 0;
1622 * The high mapping range is imprecise, so ignore the
1625 __change_page_attr_set_clr(&alias_cpa, 0);
1632 static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
1634 unsigned long numpages = cpa->numpages;
1635 unsigned long rempages = numpages;
1640 * Store the remaining nr of pages for the large page
1641 * preservation check.
1643 cpa->numpages = rempages;
1644 /* for array changes, we can't use large page */
1645 if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
1648 if (!debug_pagealloc_enabled())
1649 spin_lock(&cpa_lock);
1650 ret = __change_page_attr(cpa, checkalias);
1651 if (!debug_pagealloc_enabled())
1652 spin_unlock(&cpa_lock);
1657 ret = cpa_process_alias(cpa);
1663 * Adjust the number of pages with the result of the
1664 * CPA operation. Either a large page has been
1665 * preserved or a single page update happened.
1667 BUG_ON(cpa->numpages > rempages || !cpa->numpages);
1668 rempages -= cpa->numpages;
1669 cpa->curpage += cpa->numpages;
1673 /* Restore the original numpages */
1674 cpa->numpages = numpages;
1678 static int change_page_attr_set_clr(unsigned long *addr, int numpages,
1679 pgprot_t mask_set, pgprot_t mask_clr,
1680 int force_split, int in_flag,
1681 struct page **pages)
1683 struct cpa_data cpa;
1684 int ret, cache, checkalias;
1686 memset(&cpa, 0, sizeof(cpa));
1689 * Check, if we are requested to set a not supported
1690 * feature. Clearing non-supported features is OK.
1692 mask_set = canon_pgprot(mask_set);
1694 if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split)
1697 /* Ensure we are PAGE_SIZE aligned */
1698 if (in_flag & CPA_ARRAY) {
1700 for (i = 0; i < numpages; i++) {
1701 if (addr[i] & ~PAGE_MASK) {
1702 addr[i] &= PAGE_MASK;
1706 } else if (!(in_flag & CPA_PAGES_ARRAY)) {
1708 * in_flag of CPA_PAGES_ARRAY implies it is aligned.
1709 * No need to check in that case
1711 if (*addr & ~PAGE_MASK) {
1714 * People should not be passing in unaligned addresses:
1720 /* Must avoid aliasing mappings in the highmem code */
1721 kmap_flush_unused();
1727 cpa.numpages = numpages;
1728 cpa.mask_set = mask_set;
1729 cpa.mask_clr = mask_clr;
1732 cpa.force_split = force_split;
1734 if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY))
1735 cpa.flags |= in_flag;
1737 /* No alias checking for _NX bit modifications */
1738 checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
1739 /* Has caller explicitly disabled alias checking? */
1740 if (in_flag & CPA_NO_CHECK_ALIAS)
1743 ret = __change_page_attr_set_clr(&cpa, checkalias);
1746 * Check whether we really changed something:
1748 if (!(cpa.flags & CPA_FLUSHTLB))
1752 * No need to flush, when we did not set any of the caching
1755 cache = !!pgprot2cachemode(mask_set);
1758 * On error; flush everything to be sure.
1761 cpa_flush_all(cache);
1765 cpa_flush(&cpa, cache);
1770 static inline int change_page_attr_set(unsigned long *addr, int numpages,
1771 pgprot_t mask, int array)
1773 return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0,
1774 (array ? CPA_ARRAY : 0), NULL);
1777 static inline int change_page_attr_clear(unsigned long *addr, int numpages,
1778 pgprot_t mask, int array)
1780 return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0,
1781 (array ? CPA_ARRAY : 0), NULL);
1784 static inline int cpa_set_pages_array(struct page **pages, int numpages,
1787 return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0,
1788 CPA_PAGES_ARRAY, pages);
1791 static inline int cpa_clear_pages_array(struct page **pages, int numpages,
1794 return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0,
1795 CPA_PAGES_ARRAY, pages);
1799 * _set_memory_prot is an internal helper for callers that have been passed
1800 * a pgprot_t value from upper layers and a reservation has already been taken.
1801 * If you want to set the pgprot to a specific page protocol, use the
1802 * set_memory_xx() functions.
1804 int __set_memory_prot(unsigned long addr, int numpages, pgprot_t prot)
1806 return change_page_attr_set_clr(&addr, numpages, prot,
1807 __pgprot(~pgprot_val(prot)), 0, 0,
1811 int _set_memory_uc(unsigned long addr, int numpages)
1814 * for now UC MINUS. see comments in ioremap()
1815 * If you really need strong UC use ioremap_uc(), but note
1816 * that you cannot override IO areas with set_memory_*() as
1817 * these helpers cannot work with IO memory.
1819 return change_page_attr_set(&addr, numpages,
1820 cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
1824 int set_memory_uc(unsigned long addr, int numpages)
1829 * for now UC MINUS. see comments in ioremap()
1831 ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
1832 _PAGE_CACHE_MODE_UC_MINUS, NULL);
1836 ret = _set_memory_uc(addr, numpages);
1843 memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
1847 EXPORT_SYMBOL(set_memory_uc);
1849 int _set_memory_wc(unsigned long addr, int numpages)
1853 ret = change_page_attr_set(&addr, numpages,
1854 cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
1857 ret = change_page_attr_set_clr(&addr, numpages,
1858 cachemode2pgprot(_PAGE_CACHE_MODE_WC),
1859 __pgprot(_PAGE_CACHE_MASK),
1865 int set_memory_wc(unsigned long addr, int numpages)
1869 ret = memtype_reserve(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
1870 _PAGE_CACHE_MODE_WC, NULL);
1874 ret = _set_memory_wc(addr, numpages);
1876 memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
1880 EXPORT_SYMBOL(set_memory_wc);
1882 int _set_memory_wt(unsigned long addr, int numpages)
1884 return change_page_attr_set(&addr, numpages,
1885 cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0);
1888 int _set_memory_wb(unsigned long addr, int numpages)
1890 /* WB cache mode is hard wired to all cache attribute bits being 0 */
1891 return change_page_attr_clear(&addr, numpages,
1892 __pgprot(_PAGE_CACHE_MASK), 0);
1895 int set_memory_wb(unsigned long addr, int numpages)
1899 ret = _set_memory_wb(addr, numpages);
1903 memtype_free(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
1906 EXPORT_SYMBOL(set_memory_wb);
1908 int set_memory_x(unsigned long addr, int numpages)
1910 if (!(__supported_pte_mask & _PAGE_NX))
1913 return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0);
1916 int set_memory_nx(unsigned long addr, int numpages)
1918 if (!(__supported_pte_mask & _PAGE_NX))
1921 return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0);
1924 int set_memory_ro(unsigned long addr, int numpages)
1926 return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0);
1929 int set_memory_rw(unsigned long addr, int numpages)
1931 return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0);
1934 int set_memory_np(unsigned long addr, int numpages)
1936 return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
1939 int set_memory_np_noalias(unsigned long addr, int numpages)
1941 int cpa_flags = CPA_NO_CHECK_ALIAS;
1943 return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
1944 __pgprot(_PAGE_PRESENT), 0,
1948 int set_memory_4k(unsigned long addr, int numpages)
1950 return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
1951 __pgprot(0), 1, 0, NULL);
1954 int set_memory_nonglobal(unsigned long addr, int numpages)
1956 return change_page_attr_clear(&addr, numpages,
1957 __pgprot(_PAGE_GLOBAL), 0);
1960 int set_memory_global(unsigned long addr, int numpages)
1962 return change_page_attr_set(&addr, numpages,
1963 __pgprot(_PAGE_GLOBAL), 0);
1966 static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
1968 struct cpa_data cpa;
1971 /* Nothing to do if memory encryption is not active */
1972 if (!mem_encrypt_active())
1975 /* Should not be working on unaligned addresses */
1976 if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr))
1979 memset(&cpa, 0, sizeof(cpa));
1981 cpa.numpages = numpages;
1982 cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0);
1983 cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC);
1984 cpa.pgd = init_mm.pgd;
1986 /* Must avoid aliasing mappings in the highmem code */
1987 kmap_flush_unused();
1991 * Before changing the encryption attribute, we need to flush caches.
1995 ret = __change_page_attr_set_clr(&cpa, 1);
1998 * After changing the encryption attribute, we need to flush TLBs again
1999 * in case any speculative TLB caching occurred (but no need to flush
2000 * caches again). We could just use cpa_flush_all(), but in case TLB
2001 * flushing gets optimized in the cpa_flush() path use the same logic
2009 int set_memory_encrypted(unsigned long addr, int numpages)
2011 return __set_memory_enc_dec(addr, numpages, true);
2013 EXPORT_SYMBOL_GPL(set_memory_encrypted);
2015 int set_memory_decrypted(unsigned long addr, int numpages)
2017 return __set_memory_enc_dec(addr, numpages, false);
2019 EXPORT_SYMBOL_GPL(set_memory_decrypted);
2021 int set_pages_uc(struct page *page, int numpages)
2023 unsigned long addr = (unsigned long)page_address(page);
2025 return set_memory_uc(addr, numpages);
2027 EXPORT_SYMBOL(set_pages_uc);
2029 static int _set_pages_array(struct page **pages, int numpages,
2030 enum page_cache_mode new_type)
2032 unsigned long start;
2034 enum page_cache_mode set_type;
2039 for (i = 0; i < numpages; i++) {
2040 if (PageHighMem(pages[i]))
2042 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
2043 end = start + PAGE_SIZE;
2044 if (memtype_reserve(start, end, new_type, NULL))
2048 /* If WC, set to UC- first and then WC */
2049 set_type = (new_type == _PAGE_CACHE_MODE_WC) ?
2050 _PAGE_CACHE_MODE_UC_MINUS : new_type;
2052 ret = cpa_set_pages_array(pages, numpages,
2053 cachemode2pgprot(set_type));
2054 if (!ret && new_type == _PAGE_CACHE_MODE_WC)
2055 ret = change_page_attr_set_clr(NULL, numpages,
2057 _PAGE_CACHE_MODE_WC),
2058 __pgprot(_PAGE_CACHE_MASK),
2059 0, CPA_PAGES_ARRAY, pages);
2062 return 0; /* Success */
2065 for (i = 0; i < free_idx; i++) {
2066 if (PageHighMem(pages[i]))
2068 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
2069 end = start + PAGE_SIZE;
2070 memtype_free(start, end);
2075 int set_pages_array_uc(struct page **pages, int numpages)
2077 return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_UC_MINUS);
2079 EXPORT_SYMBOL(set_pages_array_uc);
2081 int set_pages_array_wc(struct page **pages, int numpages)
2083 return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WC);
2085 EXPORT_SYMBOL(set_pages_array_wc);
2087 int set_pages_array_wt(struct page **pages, int numpages)
2089 return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WT);
2091 EXPORT_SYMBOL_GPL(set_pages_array_wt);
2093 int set_pages_wb(struct page *page, int numpages)
2095 unsigned long addr = (unsigned long)page_address(page);
2097 return set_memory_wb(addr, numpages);
2099 EXPORT_SYMBOL(set_pages_wb);
2101 int set_pages_array_wb(struct page **pages, int numpages)
2104 unsigned long start;
2108 /* WB cache mode is hard wired to all cache attribute bits being 0 */
2109 retval = cpa_clear_pages_array(pages, numpages,
2110 __pgprot(_PAGE_CACHE_MASK));
2114 for (i = 0; i < numpages; i++) {
2115 if (PageHighMem(pages[i]))
2117 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
2118 end = start + PAGE_SIZE;
2119 memtype_free(start, end);
2124 EXPORT_SYMBOL(set_pages_array_wb);
2126 int set_pages_ro(struct page *page, int numpages)
2128 unsigned long addr = (unsigned long)page_address(page);
2130 return set_memory_ro(addr, numpages);
2133 int set_pages_rw(struct page *page, int numpages)
2135 unsigned long addr = (unsigned long)page_address(page);
2137 return set_memory_rw(addr, numpages);
2140 static int __set_pages_p(struct page *page, int numpages)
2142 unsigned long tempaddr = (unsigned long) page_address(page);
2143 struct cpa_data cpa = { .vaddr = &tempaddr,
2145 .numpages = numpages,
2146 .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW),
2147 .mask_clr = __pgprot(0),
2151 * No alias checking needed for setting present flag. otherwise,
2152 * we may need to break large pages for 64-bit kernel text
2153 * mappings (this adds to complexity if we want to do this from
2154 * atomic context especially). Let's keep it simple!
2156 return __change_page_attr_set_clr(&cpa, 0);
2159 static int __set_pages_np(struct page *page, int numpages)
2161 unsigned long tempaddr = (unsigned long) page_address(page);
2162 struct cpa_data cpa = { .vaddr = &tempaddr,
2164 .numpages = numpages,
2165 .mask_set = __pgprot(0),
2166 .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
2170 * No alias checking needed for setting not present flag. otherwise,
2171 * we may need to break large pages for 64-bit kernel text
2172 * mappings (this adds to complexity if we want to do this from
2173 * atomic context especially). Let's keep it simple!
2175 return __change_page_attr_set_clr(&cpa, 0);
2178 int set_direct_map_invalid_noflush(struct page *page)
2180 return __set_pages_np(page, 1);
2183 int set_direct_map_default_noflush(struct page *page)
2185 return __set_pages_p(page, 1);
2188 void __kernel_map_pages(struct page *page, int numpages, int enable)
2190 if (PageHighMem(page))
2193 debug_check_no_locks_freed(page_address(page),
2194 numpages * PAGE_SIZE);
2198 * The return value is ignored as the calls cannot fail.
2199 * Large pages for identity mappings are not used at boot time
2200 * and hence no memory allocations during large page split.
2203 __set_pages_p(page, numpages);
2205 __set_pages_np(page, numpages);
2208 * We should perform an IPI and flush all tlbs,
2209 * but that can deadlock->flush only current cpu.
2210 * Preemption needs to be disabled around __flush_tlb_all() due to
2211 * CR3 reload in __native_flush_tlb().
2217 arch_flush_lazy_mmu_mode();
2220 #ifdef CONFIG_HIBERNATION
2221 bool kernel_page_present(struct page *page)
2226 if (PageHighMem(page))
2229 pte = lookup_address((unsigned long)page_address(page), &level);
2230 return (pte_val(*pte) & _PAGE_PRESENT);
2232 #endif /* CONFIG_HIBERNATION */
2234 int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
2235 unsigned numpages, unsigned long page_flags)
2237 int retval = -EINVAL;
2239 struct cpa_data cpa = {
2243 .numpages = numpages,
2244 .mask_set = __pgprot(0),
2245 .mask_clr = __pgprot(~page_flags & (_PAGE_NX|_PAGE_RW)),
2249 WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
2251 if (!(__supported_pte_mask & _PAGE_NX))
2254 if (!(page_flags & _PAGE_ENC))
2255 cpa.mask_clr = pgprot_encrypted(cpa.mask_clr);
2257 cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
2259 retval = __change_page_attr_set_clr(&cpa, 0);
2267 * __flush_tlb_all() flushes mappings only on current CPU and hence this
2268 * function shouldn't be used in an SMP environment. Presently, it's used only
2269 * during boot (way before smp_init()) by EFI subsystem and hence is ok.
2271 int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
2272 unsigned long numpages)
2277 * The typical sequence for unmapping is to find a pte through
2278 * lookup_address_in_pgd() (ideally, it should never return NULL because
2279 * the address is already mapped) and change it's protections. As pfn is
2280 * the *target* of a mapping, it's not useful while unmapping.
2282 struct cpa_data cpa = {
2286 .numpages = numpages,
2287 .mask_set = __pgprot(0),
2288 .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
2292 WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
2294 retval = __change_page_attr_set_clr(&cpa, 0);
2301 * The testcases use internal knowledge of the implementation that shouldn't
2302 * be exposed to the rest of the kernel. Include these directly here.
2304 #ifdef CONFIG_CPA_DEBUG
2305 #include "cpa-test.c"