Loading...
Note: File does not exist in v6.2.
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2002 Andi Kleen, SuSE Labs.
4 * Thanks to Ben LaHaise for precious feedback.
5 */
6#include <linux/highmem.h>
7#include <linux/memblock.h>
8#include <linux/sched.h>
9#include <linux/mm.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
19#include <asm/e820/api.h>
20#include <asm/processor.h>
21#include <asm/tlbflush.h>
22#include <asm/sections.h>
23#include <asm/setup.h>
24#include <linux/uaccess.h>
25#include <asm/pgalloc.h>
26#include <asm/proto.h>
27#include <asm/pat.h>
28#include <asm/set_memory.h>
29
30#include "mm_internal.h"
31
32/*
33 * The current flushing context - we pass it instead of 5 arguments:
34 */
35struct cpa_data {
36 unsigned long *vaddr;
37 pgd_t *pgd;
38 pgprot_t mask_set;
39 pgprot_t mask_clr;
40 unsigned long numpages;
41 unsigned long curpage;
42 unsigned long pfn;
43 unsigned int flags;
44 unsigned int force_split : 1,
45 force_static_prot : 1;
46 struct page **pages;
47};
48
49enum cpa_warn {
50 CPA_CONFLICT,
51 CPA_PROTECT,
52 CPA_DETECT,
53};
54
55static const int cpa_warn_level = CPA_PROTECT;
56
57/*
58 * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings)
59 * using cpa_lock. So that we don't allow any other cpu, with stale large tlb
60 * entries change the page attribute in parallel to some other cpu
61 * splitting a large page entry along with changing the attribute.
62 */
63static DEFINE_SPINLOCK(cpa_lock);
64
65#define CPA_FLUSHTLB 1
66#define CPA_ARRAY 2
67#define CPA_PAGES_ARRAY 4
68#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */
69
70#ifdef CONFIG_PROC_FS
71static unsigned long direct_pages_count[PG_LEVEL_NUM];
72
73void update_page_count(int level, unsigned long pages)
74{
75 /* Protect against CPA */
76 spin_lock(&pgd_lock);
77 direct_pages_count[level] += pages;
78 spin_unlock(&pgd_lock);
79}
80
81static void split_page_count(int level)
82{
83 if (direct_pages_count[level] == 0)
84 return;
85
86 direct_pages_count[level]--;
87 direct_pages_count[level - 1] += PTRS_PER_PTE;
88}
89
90void arch_report_meminfo(struct seq_file *m)
91{
92 seq_printf(m, "DirectMap4k: %8lu kB\n",
93 direct_pages_count[PG_LEVEL_4K] << 2);
94#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
95 seq_printf(m, "DirectMap2M: %8lu kB\n",
96 direct_pages_count[PG_LEVEL_2M] << 11);
97#else
98 seq_printf(m, "DirectMap4M: %8lu kB\n",
99 direct_pages_count[PG_LEVEL_2M] << 12);
100#endif
101 if (direct_gbpages)
102 seq_printf(m, "DirectMap1G: %8lu kB\n",
103 direct_pages_count[PG_LEVEL_1G] << 20);
104}
105#else
106static inline void split_page_count(int level) { }
107#endif
108
109#ifdef CONFIG_X86_CPA_STATISTICS
110
111static unsigned long cpa_1g_checked;
112static unsigned long cpa_1g_sameprot;
113static unsigned long cpa_1g_preserved;
114static unsigned long cpa_2m_checked;
115static unsigned long cpa_2m_sameprot;
116static unsigned long cpa_2m_preserved;
117static unsigned long cpa_4k_install;
118
119static inline void cpa_inc_1g_checked(void)
120{
121 cpa_1g_checked++;
122}
123
124static inline void cpa_inc_2m_checked(void)
125{
126 cpa_2m_checked++;
127}
128
129static inline void cpa_inc_4k_install(void)
130{
131 cpa_4k_install++;
132}
133
134static inline void cpa_inc_lp_sameprot(int level)
135{
136 if (level == PG_LEVEL_1G)
137 cpa_1g_sameprot++;
138 else
139 cpa_2m_sameprot++;
140}
141
142static inline void cpa_inc_lp_preserved(int level)
143{
144 if (level == PG_LEVEL_1G)
145 cpa_1g_preserved++;
146 else
147 cpa_2m_preserved++;
148}
149
150static int cpastats_show(struct seq_file *m, void *p)
151{
152 seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked);
153 seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot);
154 seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved);
155 seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked);
156 seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot);
157 seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved);
158 seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install);
159 return 0;
160}
161
162static int cpastats_open(struct inode *inode, struct file *file)
163{
164 return single_open(file, cpastats_show, NULL);
165}
166
167static const struct file_operations cpastats_fops = {
168 .open = cpastats_open,
169 .read = seq_read,
170 .llseek = seq_lseek,
171 .release = single_release,
172};
173
174static int __init cpa_stats_init(void)
175{
176 debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL,
177 &cpastats_fops);
178 return 0;
179}
180late_initcall(cpa_stats_init);
181#else
182static inline void cpa_inc_1g_checked(void) { }
183static inline void cpa_inc_2m_checked(void) { }
184static inline void cpa_inc_4k_install(void) { }
185static inline void cpa_inc_lp_sameprot(int level) { }
186static inline void cpa_inc_lp_preserved(int level) { }
187#endif
188
189
190static inline int
191within(unsigned long addr, unsigned long start, unsigned long end)
192{
193 return addr >= start && addr < end;
194}
195
196static inline int
197within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
198{
199 return addr >= start && addr <= end;
200}
201
202#ifdef CONFIG_X86_64
203
204static inline unsigned long highmap_start_pfn(void)
205{
206 return __pa_symbol(_text) >> PAGE_SHIFT;
207}
208
209static inline unsigned long highmap_end_pfn(void)
210{
211 /* Do not reference physical address outside the kernel. */
212 return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT;
213}
214
215static bool __cpa_pfn_in_highmap(unsigned long pfn)
216{
217 /*
218 * Kernel text has an alias mapping at a high address, known
219 * here as "highmap".
220 */
221 return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn());
222}
223
224#else
225
226static bool __cpa_pfn_in_highmap(unsigned long pfn)
227{
228 /* There is no highmap on 32-bit */
229 return false;
230}
231
232#endif
233
234/*
235 * See set_mce_nospec().
236 *
237 * Machine check recovery code needs to change cache mode of poisoned pages to
238 * UC to avoid speculative access logging another error. But passing the
239 * address of the 1:1 mapping to set_memory_uc() is a fine way to encourage a
240 * speculative access. So we cheat and flip the top bit of the address. This
241 * works fine for the code that updates the page tables. But at the end of the
242 * process we need to flush the TLB and cache and the non-canonical address
243 * causes a #GP fault when used by the INVLPG and CLFLUSH instructions.
244 *
245 * But in the common case we already have a canonical address. This code
246 * will fix the top bit if needed and is a no-op otherwise.
247 */
248static inline unsigned long fix_addr(unsigned long addr)
249{
250#ifdef CONFIG_X86_64
251 return (long)(addr << 1) >> 1;
252#else
253 return addr;
254#endif
255}
256
257static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx)
258{
259 if (cpa->flags & CPA_PAGES_ARRAY) {
260 struct page *page = cpa->pages[idx];
261
262 if (unlikely(PageHighMem(page)))
263 return 0;
264
265 return (unsigned long)page_address(page);
266 }
267
268 if (cpa->flags & CPA_ARRAY)
269 return cpa->vaddr[idx];
270
271 return *cpa->vaddr + idx * PAGE_SIZE;
272}
273
274/*
275 * Flushing functions
276 */
277
278static void clflush_cache_range_opt(void *vaddr, unsigned int size)
279{
280 const unsigned long clflush_size = boot_cpu_data.x86_clflush_size;
281 void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1));
282 void *vend = vaddr + size;
283
284 if (p >= vend)
285 return;
286
287 for (; p < vend; p += clflush_size)
288 clflushopt(p);
289}
290
291/**
292 * clflush_cache_range - flush a cache range with clflush
293 * @vaddr: virtual start address
294 * @size: number of bytes to flush
295 *
296 * CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or
297 * SFENCE to avoid ordering issues.
298 */
299void clflush_cache_range(void *vaddr, unsigned int size)
300{
301 mb();
302 clflush_cache_range_opt(vaddr, size);
303 mb();
304}
305EXPORT_SYMBOL_GPL(clflush_cache_range);
306
307void arch_invalidate_pmem(void *addr, size_t size)
308{
309 clflush_cache_range(addr, size);
310}
311EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
312
313static void __cpa_flush_all(void *arg)
314{
315 unsigned long cache = (unsigned long)arg;
316
317 /*
318 * Flush all to work around Errata in early athlons regarding
319 * large page flushing.
320 */
321 __flush_tlb_all();
322
323 if (cache && boot_cpu_data.x86 >= 4)
324 wbinvd();
325}
326
327static void cpa_flush_all(unsigned long cache)
328{
329 BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
330
331 on_each_cpu(__cpa_flush_all, (void *) cache, 1);
332}
333
334void __cpa_flush_tlb(void *data)
335{
336 struct cpa_data *cpa = data;
337 unsigned int i;
338
339 for (i = 0; i < cpa->numpages; i++)
340 __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i)));
341}
342
343static void cpa_flush(struct cpa_data *data, int cache)
344{
345 struct cpa_data *cpa = data;
346 unsigned int i;
347
348 BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
349
350 if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) {
351 cpa_flush_all(cache);
352 return;
353 }
354
355 if (cpa->numpages <= tlb_single_page_flush_ceiling)
356 on_each_cpu(__cpa_flush_tlb, cpa, 1);
357 else
358 flush_tlb_all();
359
360 if (!cache)
361 return;
362
363 mb();
364 for (i = 0; i < cpa->numpages; i++) {
365 unsigned long addr = __cpa_addr(cpa, i);
366 unsigned int level;
367
368 pte_t *pte = lookup_address(addr, &level);
369
370 /*
371 * Only flush present addresses:
372 */
373 if (pte && (pte_val(*pte) & _PAGE_PRESENT))
374 clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE);
375 }
376 mb();
377}
378
379static bool overlaps(unsigned long r1_start, unsigned long r1_end,
380 unsigned long r2_start, unsigned long r2_end)
381{
382 return (r1_start <= r2_end && r1_end >= r2_start) ||
383 (r2_start <= r1_end && r2_end >= r1_start);
384}
385
386#ifdef CONFIG_PCI_BIOS
387/*
388 * The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS
389 * based config access (CONFIG_PCI_GOBIOS) support.
390 */
391#define BIOS_PFN PFN_DOWN(BIOS_BEGIN)
392#define BIOS_PFN_END PFN_DOWN(BIOS_END - 1)
393
394static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
395{
396 if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END))
397 return _PAGE_NX;
398 return 0;
399}
400#else
401static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn)
402{
403 return 0;
404}
405#endif
406
407/*
408 * The .rodata section needs to be read-only. Using the pfn catches all
409 * aliases. This also includes __ro_after_init, so do not enforce until
410 * kernel_set_to_readonly is true.
411 */
412static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn)
413{
414 unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata));
415
416 /*
417 * Note: __end_rodata is at page aligned and not inclusive, so
418 * subtract 1 to get the last enforced PFN in the rodata area.
419 */
420 epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1;
421
422 if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro))
423 return _PAGE_RW;
424 return 0;
425}
426
427/*
428 * Protect kernel text against becoming non executable by forbidding
429 * _PAGE_NX. This protects only the high kernel mapping (_text -> _etext)
430 * out of which the kernel actually executes. Do not protect the low
431 * mapping.
432 *
433 * This does not cover __inittext since that is gone after boot.
434 */
435static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end)
436{
437 unsigned long t_end = (unsigned long)_etext - 1;
438 unsigned long t_start = (unsigned long)_text;
439
440 if (overlaps(start, end, t_start, t_end))
441 return _PAGE_NX;
442 return 0;
443}
444
445#if defined(CONFIG_X86_64)
446/*
447 * Once the kernel maps the text as RO (kernel_set_to_readonly is set),
448 * kernel text mappings for the large page aligned text, rodata sections
449 * will be always read-only. For the kernel identity mappings covering the
450 * holes caused by this alignment can be anything that user asks.
451 *
452 * This will preserve the large page mappings for kernel text/data at no
453 * extra cost.
454 */
455static pgprotval_t protect_kernel_text_ro(unsigned long start,
456 unsigned long end)
457{
458 unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1;
459 unsigned long t_start = (unsigned long)_text;
460 unsigned int level;
461
462 if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end))
463 return 0;
464 /*
465 * Don't enforce the !RW mapping for the kernel text mapping, if
466 * the current mapping is already using small page mapping. No
467 * need to work hard to preserve large page mappings in this case.
468 *
469 * This also fixes the Linux Xen paravirt guest boot failure caused
470 * by unexpected read-only mappings for kernel identity
471 * mappings. In this paravirt guest case, the kernel text mapping
472 * and the kernel identity mapping share the same page-table pages,
473 * so the protections for kernel text and identity mappings have to
474 * be the same.
475 */
476 if (lookup_address(start, &level) && (level != PG_LEVEL_4K))
477 return _PAGE_RW;
478 return 0;
479}
480#else
481static pgprotval_t protect_kernel_text_ro(unsigned long start,
482 unsigned long end)
483{
484 return 0;
485}
486#endif
487
488static inline bool conflicts(pgprot_t prot, pgprotval_t val)
489{
490 return (pgprot_val(prot) & ~val) != pgprot_val(prot);
491}
492
493static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val,
494 unsigned long start, unsigned long end,
495 unsigned long pfn, const char *txt)
496{
497 static const char *lvltxt[] = {
498 [CPA_CONFLICT] = "conflict",
499 [CPA_PROTECT] = "protect",
500 [CPA_DETECT] = "detect",
501 };
502
503 if (warnlvl > cpa_warn_level || !conflicts(prot, val))
504 return;
505
506 pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n",
507 lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot),
508 (unsigned long long)val);
509}
510
511/*
512 * Certain areas of memory on x86 require very specific protection flags,
513 * for example the BIOS area or kernel text. Callers don't always get this
514 * right (again, ioremap() on BIOS memory is not uncommon) so this function
515 * checks and fixes these known static required protection bits.
516 */
517static inline pgprot_t static_protections(pgprot_t prot, unsigned long start,
518 unsigned long pfn, unsigned long npg,
519 unsigned long lpsize, int warnlvl)
520{
521 pgprotval_t forbidden, res;
522 unsigned long end;
523
524 /*
525 * There is no point in checking RW/NX conflicts when the requested
526 * mapping is setting the page !PRESENT.
527 */
528 if (!(pgprot_val(prot) & _PAGE_PRESENT))
529 return prot;
530
531 /* Operate on the virtual address */
532 end = start + npg * PAGE_SIZE - 1;
533
534 res = protect_kernel_text(start, end);
535 check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX");
536 forbidden = res;
537
538 /*
539 * Special case to preserve a large page. If the change spawns the
540 * full large page mapping then there is no point to split it
541 * up. Happens with ftrace and is going to be removed once ftrace
542 * switched to text_poke().
543 */
544 if (lpsize != (npg * PAGE_SIZE) || (start & (lpsize - 1))) {
545 res = protect_kernel_text_ro(start, end);
546 check_conflict(warnlvl, prot, res, start, end, pfn, "Text RO");
547 forbidden |= res;
548 }
549
550 /* Check the PFN directly */
551 res = protect_pci_bios(pfn, pfn + npg - 1);
552 check_conflict(warnlvl, prot, res, start, end, pfn, "PCIBIOS NX");
553 forbidden |= res;
554
555 res = protect_rodata(pfn, pfn + npg - 1);
556 check_conflict(warnlvl, prot, res, start, end, pfn, "Rodata RO");
557 forbidden |= res;
558
559 return __pgprot(pgprot_val(prot) & ~forbidden);
560}
561
562/*
563 * Lookup the page table entry for a virtual address in a specific pgd.
564 * Return a pointer to the entry and the level of the mapping.
565 */
566pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
567 unsigned int *level)
568{
569 p4d_t *p4d;
570 pud_t *pud;
571 pmd_t *pmd;
572
573 *level = PG_LEVEL_NONE;
574
575 if (pgd_none(*pgd))
576 return NULL;
577
578 p4d = p4d_offset(pgd, address);
579 if (p4d_none(*p4d))
580 return NULL;
581
582 *level = PG_LEVEL_512G;
583 if (p4d_large(*p4d) || !p4d_present(*p4d))
584 return (pte_t *)p4d;
585
586 pud = pud_offset(p4d, address);
587 if (pud_none(*pud))
588 return NULL;
589
590 *level = PG_LEVEL_1G;
591 if (pud_large(*pud) || !pud_present(*pud))
592 return (pte_t *)pud;
593
594 pmd = pmd_offset(pud, address);
595 if (pmd_none(*pmd))
596 return NULL;
597
598 *level = PG_LEVEL_2M;
599 if (pmd_large(*pmd) || !pmd_present(*pmd))
600 return (pte_t *)pmd;
601
602 *level = PG_LEVEL_4K;
603
604 return pte_offset_kernel(pmd, address);
605}
606
607/*
608 * Lookup the page table entry for a virtual address. Return a pointer
609 * to the entry and the level of the mapping.
610 *
611 * Note: We return pud and pmd either when the entry is marked large
612 * or when the present bit is not set. Otherwise we would return a
613 * pointer to a nonexisting mapping.
614 */
615pte_t *lookup_address(unsigned long address, unsigned int *level)
616{
617 return lookup_address_in_pgd(pgd_offset_k(address), address, level);
618}
619EXPORT_SYMBOL_GPL(lookup_address);
620
621static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
622 unsigned int *level)
623{
624 if (cpa->pgd)
625 return lookup_address_in_pgd(cpa->pgd + pgd_index(address),
626 address, level);
627
628 return lookup_address(address, level);
629}
630
631/*
632 * Lookup the PMD entry for a virtual address. Return a pointer to the entry
633 * or NULL if not present.
634 */
635pmd_t *lookup_pmd_address(unsigned long address)
636{
637 pgd_t *pgd;
638 p4d_t *p4d;
639 pud_t *pud;
640
641 pgd = pgd_offset_k(address);
642 if (pgd_none(*pgd))
643 return NULL;
644
645 p4d = p4d_offset(pgd, address);
646 if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d))
647 return NULL;
648
649 pud = pud_offset(p4d, address);
650 if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud))
651 return NULL;
652
653 return pmd_offset(pud, address);
654}
655
656/*
657 * This is necessary because __pa() does not work on some
658 * kinds of memory, like vmalloc() or the alloc_remap()
659 * areas on 32-bit NUMA systems. The percpu areas can
660 * end up in this kind of memory, for instance.
661 *
662 * This could be optimized, but it is only intended to be
663 * used at inititalization time, and keeping it
664 * unoptimized should increase the testing coverage for
665 * the more obscure platforms.
666 */
667phys_addr_t slow_virt_to_phys(void *__virt_addr)
668{
669 unsigned long virt_addr = (unsigned long)__virt_addr;
670 phys_addr_t phys_addr;
671 unsigned long offset;
672 enum pg_level level;
673 pte_t *pte;
674
675 pte = lookup_address(virt_addr, &level);
676 BUG_ON(!pte);
677
678 /*
679 * pXX_pfn() returns unsigned long, which must be cast to phys_addr_t
680 * before being left-shifted PAGE_SHIFT bits -- this trick is to
681 * make 32-PAE kernel work correctly.
682 */
683 switch (level) {
684 case PG_LEVEL_1G:
685 phys_addr = (phys_addr_t)pud_pfn(*(pud_t *)pte) << PAGE_SHIFT;
686 offset = virt_addr & ~PUD_PAGE_MASK;
687 break;
688 case PG_LEVEL_2M:
689 phys_addr = (phys_addr_t)pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT;
690 offset = virt_addr & ~PMD_PAGE_MASK;
691 break;
692 default:
693 phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
694 offset = virt_addr & ~PAGE_MASK;
695 }
696
697 return (phys_addr_t)(phys_addr | offset);
698}
699EXPORT_SYMBOL_GPL(slow_virt_to_phys);
700
701/*
702 * Set the new pmd in all the pgds we know about:
703 */
704static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
705{
706 /* change init_mm */
707 set_pte_atomic(kpte, pte);
708#ifdef CONFIG_X86_32
709 if (!SHARED_KERNEL_PMD) {
710 struct page *page;
711
712 list_for_each_entry(page, &pgd_list, lru) {
713 pgd_t *pgd;
714 p4d_t *p4d;
715 pud_t *pud;
716 pmd_t *pmd;
717
718 pgd = (pgd_t *)page_address(page) + pgd_index(address);
719 p4d = p4d_offset(pgd, address);
720 pud = pud_offset(p4d, address);
721 pmd = pmd_offset(pud, address);
722 set_pte_atomic((pte_t *)pmd, pte);
723 }
724 }
725#endif
726}
727
728static pgprot_t pgprot_clear_protnone_bits(pgprot_t prot)
729{
730 /*
731 * _PAGE_GLOBAL means "global page" for present PTEs.
732 * But, it is also used to indicate _PAGE_PROTNONE
733 * for non-present PTEs.
734 *
735 * This ensures that a _PAGE_GLOBAL PTE going from
736 * present to non-present is not confused as
737 * _PAGE_PROTNONE.
738 */
739 if (!(pgprot_val(prot) & _PAGE_PRESENT))
740 pgprot_val(prot) &= ~_PAGE_GLOBAL;
741
742 return prot;
743}
744
745static int __should_split_large_page(pte_t *kpte, unsigned long address,
746 struct cpa_data *cpa)
747{
748 unsigned long numpages, pmask, psize, lpaddr, pfn, old_pfn;
749 pgprot_t old_prot, new_prot, req_prot, chk_prot;
750 pte_t new_pte, *tmp;
751 enum pg_level level;
752
753 /*
754 * Check for races, another CPU might have split this page
755 * up already:
756 */
757 tmp = _lookup_address_cpa(cpa, address, &level);
758 if (tmp != kpte)
759 return 1;
760
761 switch (level) {
762 case PG_LEVEL_2M:
763 old_prot = pmd_pgprot(*(pmd_t *)kpte);
764 old_pfn = pmd_pfn(*(pmd_t *)kpte);
765 cpa_inc_2m_checked();
766 break;
767 case PG_LEVEL_1G:
768 old_prot = pud_pgprot(*(pud_t *)kpte);
769 old_pfn = pud_pfn(*(pud_t *)kpte);
770 cpa_inc_1g_checked();
771 break;
772 default:
773 return -EINVAL;
774 }
775
776 psize = page_level_size(level);
777 pmask = page_level_mask(level);
778
779 /*
780 * Calculate the number of pages, which fit into this large
781 * page starting at address:
782 */
783 lpaddr = (address + psize) & pmask;
784 numpages = (lpaddr - address) >> PAGE_SHIFT;
785 if (numpages < cpa->numpages)
786 cpa->numpages = numpages;
787
788 /*
789 * We are safe now. Check whether the new pgprot is the same:
790 * Convert protection attributes to 4k-format, as cpa->mask* are set
791 * up accordingly.
792 */
793
794 /* Clear PSE (aka _PAGE_PAT) and move PAT bit to correct position */
795 req_prot = pgprot_large_2_4k(old_prot);
796
797 pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr);
798 pgprot_val(req_prot) |= pgprot_val(cpa->mask_set);
799
800 /*
801 * req_prot is in format of 4k pages. It must be converted to large
802 * page format: the caching mode includes the PAT bit located at
803 * different bit positions in the two formats.
804 */
805 req_prot = pgprot_4k_2_large(req_prot);
806 req_prot = pgprot_clear_protnone_bits(req_prot);
807 if (pgprot_val(req_prot) & _PAGE_PRESENT)
808 pgprot_val(req_prot) |= _PAGE_PSE;
809
810 /*
811 * old_pfn points to the large page base pfn. So we need to add the
812 * offset of the virtual address:
813 */
814 pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT);
815 cpa->pfn = pfn;
816
817 /*
818 * Calculate the large page base address and the number of 4K pages
819 * in the large page
820 */
821 lpaddr = address & pmask;
822 numpages = psize >> PAGE_SHIFT;
823
824 /*
825 * Sanity check that the existing mapping is correct versus the static
826 * protections. static_protections() guards against !PRESENT, so no
827 * extra conditional required here.
828 */
829 chk_prot = static_protections(old_prot, lpaddr, old_pfn, numpages,
830 psize, CPA_CONFLICT);
831
832 if (WARN_ON_ONCE(pgprot_val(chk_prot) != pgprot_val(old_prot))) {
833 /*
834 * Split the large page and tell the split code to
835 * enforce static protections.
836 */
837 cpa->force_static_prot = 1;
838 return 1;
839 }
840
841 /*
842 * Optimization: If the requested pgprot is the same as the current
843 * pgprot, then the large page can be preserved and no updates are
844 * required independent of alignment and length of the requested
845 * range. The above already established that the current pgprot is
846 * correct, which in consequence makes the requested pgprot correct
847 * as well if it is the same. The static protection scan below will
848 * not come to a different conclusion.
849 */
850 if (pgprot_val(req_prot) == pgprot_val(old_prot)) {
851 cpa_inc_lp_sameprot(level);
852 return 0;
853 }
854
855 /*
856 * If the requested range does not cover the full page, split it up
857 */
858 if (address != lpaddr || cpa->numpages != numpages)
859 return 1;
860
861 /*
862 * Check whether the requested pgprot is conflicting with a static
863 * protection requirement in the large page.
864 */
865 new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages,
866 psize, CPA_DETECT);
867
868 /*
869 * If there is a conflict, split the large page.
870 *
871 * There used to be a 4k wise evaluation trying really hard to
872 * preserve the large pages, but experimentation has shown, that this
873 * does not help at all. There might be corner cases which would
874 * preserve one large page occasionally, but it's really not worth the
875 * extra code and cycles for the common case.
876 */
877 if (pgprot_val(req_prot) != pgprot_val(new_prot))
878 return 1;
879
880 /* All checks passed. Update the large page mapping. */
881 new_pte = pfn_pte(old_pfn, new_prot);
882 __set_pmd_pte(kpte, address, new_pte);
883 cpa->flags |= CPA_FLUSHTLB;
884 cpa_inc_lp_preserved(level);
885 return 0;
886}
887
888static int should_split_large_page(pte_t *kpte, unsigned long address,
889 struct cpa_data *cpa)
890{
891 int do_split;
892
893 if (cpa->force_split)
894 return 1;
895
896 spin_lock(&pgd_lock);
897 do_split = __should_split_large_page(kpte, address, cpa);
898 spin_unlock(&pgd_lock);
899
900 return do_split;
901}
902
903static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn,
904 pgprot_t ref_prot, unsigned long address,
905 unsigned long size)
906{
907 unsigned int npg = PFN_DOWN(size);
908 pgprot_t prot;
909
910 /*
911 * If should_split_large_page() discovered an inconsistent mapping,
912 * remove the invalid protection in the split mapping.
913 */
914 if (!cpa->force_static_prot)
915 goto set;
916
917 /* Hand in lpsize = 0 to enforce the protection mechanism */
918 prot = static_protections(ref_prot, address, pfn, npg, 0, CPA_PROTECT);
919
920 if (pgprot_val(prot) == pgprot_val(ref_prot))
921 goto set;
922
923 /*
924 * If this is splitting a PMD, fix it up. PUD splits cannot be
925 * fixed trivially as that would require to rescan the newly
926 * installed PMD mappings after returning from split_large_page()
927 * so an eventual further split can allocate the necessary PTE
928 * pages. Warn for now and revisit it in case this actually
929 * happens.
930 */
931 if (size == PAGE_SIZE)
932 ref_prot = prot;
933 else
934 pr_warn_once("CPA: Cannot fixup static protections for PUD split\n");
935set:
936 set_pte(pte, pfn_pte(pfn, ref_prot));
937}
938
939static int
940__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
941 struct page *base)
942{
943 unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1;
944 pte_t *pbase = (pte_t *)page_address(base);
945 unsigned int i, level;
946 pgprot_t ref_prot;
947 pte_t *tmp;
948
949 spin_lock(&pgd_lock);
950 /*
951 * Check for races, another CPU might have split this page
952 * up for us already:
953 */
954 tmp = _lookup_address_cpa(cpa, address, &level);
955 if (tmp != kpte) {
956 spin_unlock(&pgd_lock);
957 return 1;
958 }
959
960 paravirt_alloc_pte(&init_mm, page_to_pfn(base));
961
962 switch (level) {
963 case PG_LEVEL_2M:
964 ref_prot = pmd_pgprot(*(pmd_t *)kpte);
965 /*
966 * Clear PSE (aka _PAGE_PAT) and move
967 * PAT bit to correct position.
968 */
969 ref_prot = pgprot_large_2_4k(ref_prot);
970 ref_pfn = pmd_pfn(*(pmd_t *)kpte);
971 lpaddr = address & PMD_MASK;
972 lpinc = PAGE_SIZE;
973 break;
974
975 case PG_LEVEL_1G:
976 ref_prot = pud_pgprot(*(pud_t *)kpte);
977 ref_pfn = pud_pfn(*(pud_t *)kpte);
978 pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT;
979 lpaddr = address & PUD_MASK;
980 lpinc = PMD_SIZE;
981 /*
982 * Clear the PSE flags if the PRESENT flag is not set
983 * otherwise pmd_present/pmd_huge will return true
984 * even on a non present pmd.
985 */
986 if (!(pgprot_val(ref_prot) & _PAGE_PRESENT))
987 pgprot_val(ref_prot) &= ~_PAGE_PSE;
988 break;
989
990 default:
991 spin_unlock(&pgd_lock);
992 return 1;
993 }
994
995 ref_prot = pgprot_clear_protnone_bits(ref_prot);
996
997 /*
998 * Get the target pfn from the original entry:
999 */
1000 pfn = ref_pfn;
1001 for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc, lpaddr += lpinc)
1002 split_set_pte(cpa, pbase + i, pfn, ref_prot, lpaddr, lpinc);
1003
1004 if (virt_addr_valid(address)) {
1005 unsigned long pfn = PFN_DOWN(__pa(address));
1006
1007 if (pfn_range_is_mapped(pfn, pfn + 1))
1008 split_page_count(level);
1009 }
1010
1011 /*
1012 * Install the new, split up pagetable.
1013 *
1014 * We use the standard kernel pagetable protections for the new
1015 * pagetable protections, the actual ptes set above control the
1016 * primary protection behavior:
1017 */
1018 __set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE)));
1019
1020 /*
1021 * Do a global flush tlb after splitting the large page
1022 * and before we do the actual change page attribute in the PTE.
1023 *
1024 * Without this, we violate the TLB application note, that says:
1025 * "The TLBs may contain both ordinary and large-page
1026 * translations for a 4-KByte range of linear addresses. This
1027 * may occur if software modifies the paging structures so that
1028 * the page size used for the address range changes. If the two
1029 * translations differ with respect to page frame or attributes
1030 * (e.g., permissions), processor behavior is undefined and may
1031 * be implementation-specific."
1032 *
1033 * We do this global tlb flush inside the cpa_lock, so that we
1034 * don't allow any other cpu, with stale tlb entries change the
1035 * page attribute in parallel, that also falls into the
1036 * just split large page entry.
1037 */
1038 flush_tlb_all();
1039 spin_unlock(&pgd_lock);
1040
1041 return 0;
1042}
1043
1044static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
1045 unsigned long address)
1046{
1047 struct page *base;
1048
1049 if (!debug_pagealloc_enabled())
1050 spin_unlock(&cpa_lock);
1051 base = alloc_pages(GFP_KERNEL, 0);
1052 if (!debug_pagealloc_enabled())
1053 spin_lock(&cpa_lock);
1054 if (!base)
1055 return -ENOMEM;
1056
1057 if (__split_large_page(cpa, kpte, address, base))
1058 __free_page(base);
1059
1060 return 0;
1061}
1062
1063static bool try_to_free_pte_page(pte_t *pte)
1064{
1065 int i;
1066
1067 for (i = 0; i < PTRS_PER_PTE; i++)
1068 if (!pte_none(pte[i]))
1069 return false;
1070
1071 free_page((unsigned long)pte);
1072 return true;
1073}
1074
1075static bool try_to_free_pmd_page(pmd_t *pmd)
1076{
1077 int i;
1078
1079 for (i = 0; i < PTRS_PER_PMD; i++)
1080 if (!pmd_none(pmd[i]))
1081 return false;
1082
1083 free_page((unsigned long)pmd);
1084 return true;
1085}
1086
1087static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
1088{
1089 pte_t *pte = pte_offset_kernel(pmd, start);
1090
1091 while (start < end) {
1092 set_pte(pte, __pte(0));
1093
1094 start += PAGE_SIZE;
1095 pte++;
1096 }
1097
1098 if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
1099 pmd_clear(pmd);
1100 return true;
1101 }
1102 return false;
1103}
1104
1105static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd,
1106 unsigned long start, unsigned long end)
1107{
1108 if (unmap_pte_range(pmd, start, end))
1109 if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
1110 pud_clear(pud);
1111}
1112
1113static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
1114{
1115 pmd_t *pmd = pmd_offset(pud, start);
1116
1117 /*
1118 * Not on a 2MB page boundary?
1119 */
1120 if (start & (PMD_SIZE - 1)) {
1121 unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
1122 unsigned long pre_end = min_t(unsigned long, end, next_page);
1123
1124 __unmap_pmd_range(pud, pmd, start, pre_end);
1125
1126 start = pre_end;
1127 pmd++;
1128 }
1129
1130 /*
1131 * Try to unmap in 2M chunks.
1132 */
1133 while (end - start >= PMD_SIZE) {
1134 if (pmd_large(*pmd))
1135 pmd_clear(pmd);
1136 else
1137 __unmap_pmd_range(pud, pmd, start, start + PMD_SIZE);
1138
1139 start += PMD_SIZE;
1140 pmd++;
1141 }
1142
1143 /*
1144 * 4K leftovers?
1145 */
1146 if (start < end)
1147 return __unmap_pmd_range(pud, pmd, start, end);
1148
1149 /*
1150 * Try again to free the PMD page if haven't succeeded above.
1151 */
1152 if (!pud_none(*pud))
1153 if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
1154 pud_clear(pud);
1155}
1156
1157static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end)
1158{
1159 pud_t *pud = pud_offset(p4d, start);
1160
1161 /*
1162 * Not on a GB page boundary?
1163 */
1164 if (start & (PUD_SIZE - 1)) {
1165 unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
1166 unsigned long pre_end = min_t(unsigned long, end, next_page);
1167
1168 unmap_pmd_range(pud, start, pre_end);
1169
1170 start = pre_end;
1171 pud++;
1172 }
1173
1174 /*
1175 * Try to unmap in 1G chunks?
1176 */
1177 while (end - start >= PUD_SIZE) {
1178
1179 if (pud_large(*pud))
1180 pud_clear(pud);
1181 else
1182 unmap_pmd_range(pud, start, start + PUD_SIZE);
1183
1184 start += PUD_SIZE;
1185 pud++;
1186 }
1187
1188 /*
1189 * 2M leftovers?
1190 */
1191 if (start < end)
1192 unmap_pmd_range(pud, start, end);
1193
1194 /*
1195 * No need to try to free the PUD page because we'll free it in
1196 * populate_pgd's error path
1197 */
1198}
1199
1200static int alloc_pte_page(pmd_t *pmd)
1201{
1202 pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
1203 if (!pte)
1204 return -1;
1205
1206 set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
1207 return 0;
1208}
1209
1210static int alloc_pmd_page(pud_t *pud)
1211{
1212 pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
1213 if (!pmd)
1214 return -1;
1215
1216 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
1217 return 0;
1218}
1219
1220static void populate_pte(struct cpa_data *cpa,
1221 unsigned long start, unsigned long end,
1222 unsigned num_pages, pmd_t *pmd, pgprot_t pgprot)
1223{
1224 pte_t *pte;
1225
1226 pte = pte_offset_kernel(pmd, start);
1227
1228 pgprot = pgprot_clear_protnone_bits(pgprot);
1229
1230 while (num_pages-- && start < end) {
1231 set_pte(pte, pfn_pte(cpa->pfn, pgprot));
1232
1233 start += PAGE_SIZE;
1234 cpa->pfn++;
1235 pte++;
1236 }
1237}
1238
1239static long populate_pmd(struct cpa_data *cpa,
1240 unsigned long start, unsigned long end,
1241 unsigned num_pages, pud_t *pud, pgprot_t pgprot)
1242{
1243 long cur_pages = 0;
1244 pmd_t *pmd;
1245 pgprot_t pmd_pgprot;
1246
1247 /*
1248 * Not on a 2M boundary?
1249 */
1250 if (start & (PMD_SIZE - 1)) {
1251 unsigned long pre_end = start + (num_pages << PAGE_SHIFT);
1252 unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
1253
1254 pre_end = min_t(unsigned long, pre_end, next_page);
1255 cur_pages = (pre_end - start) >> PAGE_SHIFT;
1256 cur_pages = min_t(unsigned int, num_pages, cur_pages);
1257
1258 /*
1259 * Need a PTE page?
1260 */
1261 pmd = pmd_offset(pud, start);
1262 if (pmd_none(*pmd))
1263 if (alloc_pte_page(pmd))
1264 return -1;
1265
1266 populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
1267
1268 start = pre_end;
1269 }
1270
1271 /*
1272 * We mapped them all?
1273 */
1274 if (num_pages == cur_pages)
1275 return cur_pages;
1276
1277 pmd_pgprot = pgprot_4k_2_large(pgprot);
1278
1279 while (end - start >= PMD_SIZE) {
1280
1281 /*
1282 * We cannot use a 1G page so allocate a PMD page if needed.
1283 */
1284 if (pud_none(*pud))
1285 if (alloc_pmd_page(pud))
1286 return -1;
1287
1288 pmd = pmd_offset(pud, start);
1289
1290 set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn,
1291 canon_pgprot(pmd_pgprot))));
1292
1293 start += PMD_SIZE;
1294 cpa->pfn += PMD_SIZE >> PAGE_SHIFT;
1295 cur_pages += PMD_SIZE >> PAGE_SHIFT;
1296 }
1297
1298 /*
1299 * Map trailing 4K pages.
1300 */
1301 if (start < end) {
1302 pmd = pmd_offset(pud, start);
1303 if (pmd_none(*pmd))
1304 if (alloc_pte_page(pmd))
1305 return -1;
1306
1307 populate_pte(cpa, start, end, num_pages - cur_pages,
1308 pmd, pgprot);
1309 }
1310 return num_pages;
1311}
1312
1313static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d,
1314 pgprot_t pgprot)
1315{
1316 pud_t *pud;
1317 unsigned long end;
1318 long cur_pages = 0;
1319 pgprot_t pud_pgprot;
1320
1321 end = start + (cpa->numpages << PAGE_SHIFT);
1322
1323 /*
1324 * Not on a Gb page boundary? => map everything up to it with
1325 * smaller pages.
1326 */
1327 if (start & (PUD_SIZE - 1)) {
1328 unsigned long pre_end;
1329 unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
1330
1331 pre_end = min_t(unsigned long, end, next_page);
1332 cur_pages = (pre_end - start) >> PAGE_SHIFT;
1333 cur_pages = min_t(int, (int)cpa->numpages, cur_pages);
1334
1335 pud = pud_offset(p4d, start);
1336
1337 /*
1338 * Need a PMD page?
1339 */
1340 if (pud_none(*pud))
1341 if (alloc_pmd_page(pud))
1342 return -1;
1343
1344 cur_pages = populate_pmd(cpa, start, pre_end, cur_pages,
1345 pud, pgprot);
1346 if (cur_pages < 0)
1347 return cur_pages;
1348
1349 start = pre_end;
1350 }
1351
1352 /* We mapped them all? */
1353 if (cpa->numpages == cur_pages)
1354 return cur_pages;
1355
1356 pud = pud_offset(p4d, start);
1357 pud_pgprot = pgprot_4k_2_large(pgprot);
1358
1359 /*
1360 * Map everything starting from the Gb boundary, possibly with 1G pages
1361 */
1362 while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) {
1363 set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
1364 canon_pgprot(pud_pgprot))));
1365
1366 start += PUD_SIZE;
1367 cpa->pfn += PUD_SIZE >> PAGE_SHIFT;
1368 cur_pages += PUD_SIZE >> PAGE_SHIFT;
1369 pud++;
1370 }
1371
1372 /* Map trailing leftover */
1373 if (start < end) {
1374 long tmp;
1375
1376 pud = pud_offset(p4d, start);
1377 if (pud_none(*pud))
1378 if (alloc_pmd_page(pud))
1379 return -1;
1380
1381 tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages,
1382 pud, pgprot);
1383 if (tmp < 0)
1384 return cur_pages;
1385
1386 cur_pages += tmp;
1387 }
1388 return cur_pages;
1389}
1390
1391/*
1392 * Restrictions for kernel page table do not necessarily apply when mapping in
1393 * an alternate PGD.
1394 */
1395static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
1396{
1397 pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
1398 pud_t *pud = NULL; /* shut up gcc */
1399 p4d_t *p4d;
1400 pgd_t *pgd_entry;
1401 long ret;
1402
1403 pgd_entry = cpa->pgd + pgd_index(addr);
1404
1405 if (pgd_none(*pgd_entry)) {
1406 p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL);
1407 if (!p4d)
1408 return -1;
1409
1410 set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE));
1411 }
1412
1413 /*
1414 * Allocate a PUD page and hand it down for mapping.
1415 */
1416 p4d = p4d_offset(pgd_entry, addr);
1417 if (p4d_none(*p4d)) {
1418 pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
1419 if (!pud)
1420 return -1;
1421
1422 set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE));
1423 }
1424
1425 pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr);
1426 pgprot_val(pgprot) |= pgprot_val(cpa->mask_set);
1427
1428 ret = populate_pud(cpa, addr, p4d, pgprot);
1429 if (ret < 0) {
1430 /*
1431 * Leave the PUD page in place in case some other CPU or thread
1432 * already found it, but remove any useless entries we just
1433 * added to it.
1434 */
1435 unmap_pud_range(p4d, addr,
1436 addr + (cpa->numpages << PAGE_SHIFT));
1437 return ret;
1438 }
1439
1440 cpa->numpages = ret;
1441 return 0;
1442}
1443
1444static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
1445 int primary)
1446{
1447 if (cpa->pgd) {
1448 /*
1449 * Right now, we only execute this code path when mapping
1450 * the EFI virtual memory map regions, no other users
1451 * provide a ->pgd value. This may change in the future.
1452 */
1453 return populate_pgd(cpa, vaddr);
1454 }
1455
1456 /*
1457 * Ignore all non primary paths.
1458 */
1459 if (!primary) {
1460 cpa->numpages = 1;
1461 return 0;
1462 }
1463
1464 /*
1465 * Ignore the NULL PTE for kernel identity mapping, as it is expected
1466 * to have holes.
1467 * Also set numpages to '1' indicating that we processed cpa req for
1468 * one virtual address page and its pfn. TBD: numpages can be set based
1469 * on the initial value and the level returned by lookup_address().
1470 */
1471 if (within(vaddr, PAGE_OFFSET,
1472 PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) {
1473 cpa->numpages = 1;
1474 cpa->pfn = __pa(vaddr) >> PAGE_SHIFT;
1475 return 0;
1476
1477 } else if (__cpa_pfn_in_highmap(cpa->pfn)) {
1478 /* Faults in the highmap are OK, so do not warn: */
1479 return -EFAULT;
1480 } else {
1481 WARN(1, KERN_WARNING "CPA: called for zero pte. "
1482 "vaddr = %lx cpa->vaddr = %lx\n", vaddr,
1483 *cpa->vaddr);
1484
1485 return -EFAULT;
1486 }
1487}
1488
1489static int __change_page_attr(struct cpa_data *cpa, int primary)
1490{
1491 unsigned long address;
1492 int do_split, err;
1493 unsigned int level;
1494 pte_t *kpte, old_pte;
1495
1496 address = __cpa_addr(cpa, cpa->curpage);
1497repeat:
1498 kpte = _lookup_address_cpa(cpa, address, &level);
1499 if (!kpte)
1500 return __cpa_process_fault(cpa, address, primary);
1501
1502 old_pte = *kpte;
1503 if (pte_none(old_pte))
1504 return __cpa_process_fault(cpa, address, primary);
1505
1506 if (level == PG_LEVEL_4K) {
1507 pte_t new_pte;
1508 pgprot_t new_prot = pte_pgprot(old_pte);
1509 unsigned long pfn = pte_pfn(old_pte);
1510
1511 pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
1512 pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
1513
1514 cpa_inc_4k_install();
1515 /* Hand in lpsize = 0 to enforce the protection mechanism */
1516 new_prot = static_protections(new_prot, address, pfn, 1, 0,
1517 CPA_PROTECT);
1518
1519 new_prot = pgprot_clear_protnone_bits(new_prot);
1520
1521 /*
1522 * We need to keep the pfn from the existing PTE,
1523 * after all we're only going to change it's attributes
1524 * not the memory it points to
1525 */
1526 new_pte = pfn_pte(pfn, new_prot);
1527 cpa->pfn = pfn;
1528 /*
1529 * Do we really change anything ?
1530 */
1531 if (pte_val(old_pte) != pte_val(new_pte)) {
1532 set_pte_atomic(kpte, new_pte);
1533 cpa->flags |= CPA_FLUSHTLB;
1534 }
1535 cpa->numpages = 1;
1536 return 0;
1537 }
1538
1539 /*
1540 * Check, whether we can keep the large page intact
1541 * and just change the pte:
1542 */
1543 do_split = should_split_large_page(kpte, address, cpa);
1544 /*
1545 * When the range fits into the existing large page,
1546 * return. cp->numpages and cpa->tlbflush have been updated in
1547 * try_large_page:
1548 */
1549 if (do_split <= 0)
1550 return do_split;
1551
1552 /*
1553 * We have to split the large page:
1554 */
1555 err = split_large_page(cpa, kpte, address);
1556 if (!err)
1557 goto repeat;
1558
1559 return err;
1560}
1561
1562static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias);
1563
1564static int cpa_process_alias(struct cpa_data *cpa)
1565{
1566 struct cpa_data alias_cpa;
1567 unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT);
1568 unsigned long vaddr;
1569 int ret;
1570
1571 if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1))
1572 return 0;
1573
1574 /*
1575 * No need to redo, when the primary call touched the direct
1576 * mapping already:
1577 */
1578 vaddr = __cpa_addr(cpa, cpa->curpage);
1579 if (!(within(vaddr, PAGE_OFFSET,
1580 PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) {
1581
1582 alias_cpa = *cpa;
1583 alias_cpa.vaddr = &laddr;
1584 alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
1585 alias_cpa.curpage = 0;
1586
1587 ret = __change_page_attr_set_clr(&alias_cpa, 0);
1588 if (ret)
1589 return ret;
1590 }
1591
1592#ifdef CONFIG_X86_64
1593 /*
1594 * If the primary call didn't touch the high mapping already
1595 * and the physical address is inside the kernel map, we need
1596 * to touch the high mapped kernel as well:
1597 */
1598 if (!within(vaddr, (unsigned long)_text, _brk_end) &&
1599 __cpa_pfn_in_highmap(cpa->pfn)) {
1600 unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) +
1601 __START_KERNEL_map - phys_base;
1602 alias_cpa = *cpa;
1603 alias_cpa.vaddr = &temp_cpa_vaddr;
1604 alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY);
1605 alias_cpa.curpage = 0;
1606
1607 /*
1608 * The high mapping range is imprecise, so ignore the
1609 * return value.
1610 */
1611 __change_page_attr_set_clr(&alias_cpa, 0);
1612 }
1613#endif
1614
1615 return 0;
1616}
1617
1618static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
1619{
1620 unsigned long numpages = cpa->numpages;
1621 unsigned long rempages = numpages;
1622 int ret = 0;
1623
1624 while (rempages) {
1625 /*
1626 * Store the remaining nr of pages for the large page
1627 * preservation check.
1628 */
1629 cpa->numpages = rempages;
1630 /* for array changes, we can't use large page */
1631 if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
1632 cpa->numpages = 1;
1633
1634 if (!debug_pagealloc_enabled())
1635 spin_lock(&cpa_lock);
1636 ret = __change_page_attr(cpa, checkalias);
1637 if (!debug_pagealloc_enabled())
1638 spin_unlock(&cpa_lock);
1639 if (ret)
1640 goto out;
1641
1642 if (checkalias) {
1643 ret = cpa_process_alias(cpa);
1644 if (ret)
1645 goto out;
1646 }
1647
1648 /*
1649 * Adjust the number of pages with the result of the
1650 * CPA operation. Either a large page has been
1651 * preserved or a single page update happened.
1652 */
1653 BUG_ON(cpa->numpages > rempages || !cpa->numpages);
1654 rempages -= cpa->numpages;
1655 cpa->curpage += cpa->numpages;
1656 }
1657
1658out:
1659 /* Restore the original numpages */
1660 cpa->numpages = numpages;
1661 return ret;
1662}
1663
1664static int change_page_attr_set_clr(unsigned long *addr, int numpages,
1665 pgprot_t mask_set, pgprot_t mask_clr,
1666 int force_split, int in_flag,
1667 struct page **pages)
1668{
1669 struct cpa_data cpa;
1670 int ret, cache, checkalias;
1671
1672 memset(&cpa, 0, sizeof(cpa));
1673
1674 /*
1675 * Check, if we are requested to set a not supported
1676 * feature. Clearing non-supported features is OK.
1677 */
1678 mask_set = canon_pgprot(mask_set);
1679
1680 if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split)
1681 return 0;
1682
1683 /* Ensure we are PAGE_SIZE aligned */
1684 if (in_flag & CPA_ARRAY) {
1685 int i;
1686 for (i = 0; i < numpages; i++) {
1687 if (addr[i] & ~PAGE_MASK) {
1688 addr[i] &= PAGE_MASK;
1689 WARN_ON_ONCE(1);
1690 }
1691 }
1692 } else if (!(in_flag & CPA_PAGES_ARRAY)) {
1693 /*
1694 * in_flag of CPA_PAGES_ARRAY implies it is aligned.
1695 * No need to check in that case
1696 */
1697 if (*addr & ~PAGE_MASK) {
1698 *addr &= PAGE_MASK;
1699 /*
1700 * People should not be passing in unaligned addresses:
1701 */
1702 WARN_ON_ONCE(1);
1703 }
1704 }
1705
1706 /* Must avoid aliasing mappings in the highmem code */
1707 kmap_flush_unused();
1708
1709 vm_unmap_aliases();
1710
1711 cpa.vaddr = addr;
1712 cpa.pages = pages;
1713 cpa.numpages = numpages;
1714 cpa.mask_set = mask_set;
1715 cpa.mask_clr = mask_clr;
1716 cpa.flags = 0;
1717 cpa.curpage = 0;
1718 cpa.force_split = force_split;
1719
1720 if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY))
1721 cpa.flags |= in_flag;
1722
1723 /* No alias checking for _NX bit modifications */
1724 checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX;
1725 /* Has caller explicitly disabled alias checking? */
1726 if (in_flag & CPA_NO_CHECK_ALIAS)
1727 checkalias = 0;
1728
1729 ret = __change_page_attr_set_clr(&cpa, checkalias);
1730
1731 /*
1732 * Check whether we really changed something:
1733 */
1734 if (!(cpa.flags & CPA_FLUSHTLB))
1735 goto out;
1736
1737 /*
1738 * No need to flush, when we did not set any of the caching
1739 * attributes:
1740 */
1741 cache = !!pgprot2cachemode(mask_set);
1742
1743 /*
1744 * On error; flush everything to be sure.
1745 */
1746 if (ret) {
1747 cpa_flush_all(cache);
1748 goto out;
1749 }
1750
1751 cpa_flush(&cpa, cache);
1752out:
1753 return ret;
1754}
1755
1756static inline int change_page_attr_set(unsigned long *addr, int numpages,
1757 pgprot_t mask, int array)
1758{
1759 return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0,
1760 (array ? CPA_ARRAY : 0), NULL);
1761}
1762
1763static inline int change_page_attr_clear(unsigned long *addr, int numpages,
1764 pgprot_t mask, int array)
1765{
1766 return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0,
1767 (array ? CPA_ARRAY : 0), NULL);
1768}
1769
1770static inline int cpa_set_pages_array(struct page **pages, int numpages,
1771 pgprot_t mask)
1772{
1773 return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0,
1774 CPA_PAGES_ARRAY, pages);
1775}
1776
1777static inline int cpa_clear_pages_array(struct page **pages, int numpages,
1778 pgprot_t mask)
1779{
1780 return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0,
1781 CPA_PAGES_ARRAY, pages);
1782}
1783
1784int _set_memory_uc(unsigned long addr, int numpages)
1785{
1786 /*
1787 * for now UC MINUS. see comments in ioremap_nocache()
1788 * If you really need strong UC use ioremap_uc(), but note
1789 * that you cannot override IO areas with set_memory_*() as
1790 * these helpers cannot work with IO memory.
1791 */
1792 return change_page_attr_set(&addr, numpages,
1793 cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
1794 0);
1795}
1796
1797int set_memory_uc(unsigned long addr, int numpages)
1798{
1799 int ret;
1800
1801 /*
1802 * for now UC MINUS. see comments in ioremap_nocache()
1803 */
1804 ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
1805 _PAGE_CACHE_MODE_UC_MINUS, NULL);
1806 if (ret)
1807 goto out_err;
1808
1809 ret = _set_memory_uc(addr, numpages);
1810 if (ret)
1811 goto out_free;
1812
1813 return 0;
1814
1815out_free:
1816 free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
1817out_err:
1818 return ret;
1819}
1820EXPORT_SYMBOL(set_memory_uc);
1821
1822int _set_memory_wc(unsigned long addr, int numpages)
1823{
1824 int ret;
1825
1826 ret = change_page_attr_set(&addr, numpages,
1827 cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS),
1828 0);
1829 if (!ret) {
1830 ret = change_page_attr_set_clr(&addr, numpages,
1831 cachemode2pgprot(_PAGE_CACHE_MODE_WC),
1832 __pgprot(_PAGE_CACHE_MASK),
1833 0, 0, NULL);
1834 }
1835 return ret;
1836}
1837
1838int set_memory_wc(unsigned long addr, int numpages)
1839{
1840 int ret;
1841
1842 ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE,
1843 _PAGE_CACHE_MODE_WC, NULL);
1844 if (ret)
1845 return ret;
1846
1847 ret = _set_memory_wc(addr, numpages);
1848 if (ret)
1849 free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
1850
1851 return ret;
1852}
1853EXPORT_SYMBOL(set_memory_wc);
1854
1855int _set_memory_wt(unsigned long addr, int numpages)
1856{
1857 return change_page_attr_set(&addr, numpages,
1858 cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0);
1859}
1860
1861int _set_memory_wb(unsigned long addr, int numpages)
1862{
1863 /* WB cache mode is hard wired to all cache attribute bits being 0 */
1864 return change_page_attr_clear(&addr, numpages,
1865 __pgprot(_PAGE_CACHE_MASK), 0);
1866}
1867
1868int set_memory_wb(unsigned long addr, int numpages)
1869{
1870 int ret;
1871
1872 ret = _set_memory_wb(addr, numpages);
1873 if (ret)
1874 return ret;
1875
1876 free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE);
1877 return 0;
1878}
1879EXPORT_SYMBOL(set_memory_wb);
1880
1881int set_memory_x(unsigned long addr, int numpages)
1882{
1883 if (!(__supported_pte_mask & _PAGE_NX))
1884 return 0;
1885
1886 return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0);
1887}
1888
1889int set_memory_nx(unsigned long addr, int numpages)
1890{
1891 if (!(__supported_pte_mask & _PAGE_NX))
1892 return 0;
1893
1894 return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0);
1895}
1896
1897int set_memory_ro(unsigned long addr, int numpages)
1898{
1899 return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0);
1900}
1901
1902int set_memory_rw(unsigned long addr, int numpages)
1903{
1904 return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0);
1905}
1906
1907int set_memory_np(unsigned long addr, int numpages)
1908{
1909 return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
1910}
1911
1912int set_memory_np_noalias(unsigned long addr, int numpages)
1913{
1914 int cpa_flags = CPA_NO_CHECK_ALIAS;
1915
1916 return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
1917 __pgprot(_PAGE_PRESENT), 0,
1918 cpa_flags, NULL);
1919}
1920
1921int set_memory_4k(unsigned long addr, int numpages)
1922{
1923 return change_page_attr_set_clr(&addr, numpages, __pgprot(0),
1924 __pgprot(0), 1, 0, NULL);
1925}
1926
1927int set_memory_nonglobal(unsigned long addr, int numpages)
1928{
1929 return change_page_attr_clear(&addr, numpages,
1930 __pgprot(_PAGE_GLOBAL), 0);
1931}
1932
1933int set_memory_global(unsigned long addr, int numpages)
1934{
1935 return change_page_attr_set(&addr, numpages,
1936 __pgprot(_PAGE_GLOBAL), 0);
1937}
1938
1939static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc)
1940{
1941 struct cpa_data cpa;
1942 int ret;
1943
1944 /* Nothing to do if memory encryption is not active */
1945 if (!mem_encrypt_active())
1946 return 0;
1947
1948 /* Should not be working on unaligned addresses */
1949 if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr))
1950 addr &= PAGE_MASK;
1951
1952 memset(&cpa, 0, sizeof(cpa));
1953 cpa.vaddr = &addr;
1954 cpa.numpages = numpages;
1955 cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0);
1956 cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC);
1957 cpa.pgd = init_mm.pgd;
1958
1959 /* Must avoid aliasing mappings in the highmem code */
1960 kmap_flush_unused();
1961 vm_unmap_aliases();
1962
1963 /*
1964 * Before changing the encryption attribute, we need to flush caches.
1965 */
1966 cpa_flush(&cpa, 1);
1967
1968 ret = __change_page_attr_set_clr(&cpa, 1);
1969
1970 /*
1971 * After changing the encryption attribute, we need to flush TLBs again
1972 * in case any speculative TLB caching occurred (but no need to flush
1973 * caches again). We could just use cpa_flush_all(), but in case TLB
1974 * flushing gets optimized in the cpa_flush() path use the same logic
1975 * as above.
1976 */
1977 cpa_flush(&cpa, 0);
1978
1979 return ret;
1980}
1981
1982int set_memory_encrypted(unsigned long addr, int numpages)
1983{
1984 return __set_memory_enc_dec(addr, numpages, true);
1985}
1986EXPORT_SYMBOL_GPL(set_memory_encrypted);
1987
1988int set_memory_decrypted(unsigned long addr, int numpages)
1989{
1990 return __set_memory_enc_dec(addr, numpages, false);
1991}
1992EXPORT_SYMBOL_GPL(set_memory_decrypted);
1993
1994int set_pages_uc(struct page *page, int numpages)
1995{
1996 unsigned long addr = (unsigned long)page_address(page);
1997
1998 return set_memory_uc(addr, numpages);
1999}
2000EXPORT_SYMBOL(set_pages_uc);
2001
2002static int _set_pages_array(struct page **pages, int numpages,
2003 enum page_cache_mode new_type)
2004{
2005 unsigned long start;
2006 unsigned long end;
2007 enum page_cache_mode set_type;
2008 int i;
2009 int free_idx;
2010 int ret;
2011
2012 for (i = 0; i < numpages; i++) {
2013 if (PageHighMem(pages[i]))
2014 continue;
2015 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
2016 end = start + PAGE_SIZE;
2017 if (reserve_memtype(start, end, new_type, NULL))
2018 goto err_out;
2019 }
2020
2021 /* If WC, set to UC- first and then WC */
2022 set_type = (new_type == _PAGE_CACHE_MODE_WC) ?
2023 _PAGE_CACHE_MODE_UC_MINUS : new_type;
2024
2025 ret = cpa_set_pages_array(pages, numpages,
2026 cachemode2pgprot(set_type));
2027 if (!ret && new_type == _PAGE_CACHE_MODE_WC)
2028 ret = change_page_attr_set_clr(NULL, numpages,
2029 cachemode2pgprot(
2030 _PAGE_CACHE_MODE_WC),
2031 __pgprot(_PAGE_CACHE_MASK),
2032 0, CPA_PAGES_ARRAY, pages);
2033 if (ret)
2034 goto err_out;
2035 return 0; /* Success */
2036err_out:
2037 free_idx = i;
2038 for (i = 0; i < free_idx; i++) {
2039 if (PageHighMem(pages[i]))
2040 continue;
2041 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
2042 end = start + PAGE_SIZE;
2043 free_memtype(start, end);
2044 }
2045 return -EINVAL;
2046}
2047
2048int set_pages_array_uc(struct page **pages, int numpages)
2049{
2050 return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_UC_MINUS);
2051}
2052EXPORT_SYMBOL(set_pages_array_uc);
2053
2054int set_pages_array_wc(struct page **pages, int numpages)
2055{
2056 return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WC);
2057}
2058EXPORT_SYMBOL(set_pages_array_wc);
2059
2060int set_pages_array_wt(struct page **pages, int numpages)
2061{
2062 return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WT);
2063}
2064EXPORT_SYMBOL_GPL(set_pages_array_wt);
2065
2066int set_pages_wb(struct page *page, int numpages)
2067{
2068 unsigned long addr = (unsigned long)page_address(page);
2069
2070 return set_memory_wb(addr, numpages);
2071}
2072EXPORT_SYMBOL(set_pages_wb);
2073
2074int set_pages_array_wb(struct page **pages, int numpages)
2075{
2076 int retval;
2077 unsigned long start;
2078 unsigned long end;
2079 int i;
2080
2081 /* WB cache mode is hard wired to all cache attribute bits being 0 */
2082 retval = cpa_clear_pages_array(pages, numpages,
2083 __pgprot(_PAGE_CACHE_MASK));
2084 if (retval)
2085 return retval;
2086
2087 for (i = 0; i < numpages; i++) {
2088 if (PageHighMem(pages[i]))
2089 continue;
2090 start = page_to_pfn(pages[i]) << PAGE_SHIFT;
2091 end = start + PAGE_SIZE;
2092 free_memtype(start, end);
2093 }
2094
2095 return 0;
2096}
2097EXPORT_SYMBOL(set_pages_array_wb);
2098
2099int set_pages_ro(struct page *page, int numpages)
2100{
2101 unsigned long addr = (unsigned long)page_address(page);
2102
2103 return set_memory_ro(addr, numpages);
2104}
2105
2106int set_pages_rw(struct page *page, int numpages)
2107{
2108 unsigned long addr = (unsigned long)page_address(page);
2109
2110 return set_memory_rw(addr, numpages);
2111}
2112
2113static int __set_pages_p(struct page *page, int numpages)
2114{
2115 unsigned long tempaddr = (unsigned long) page_address(page);
2116 struct cpa_data cpa = { .vaddr = &tempaddr,
2117 .pgd = NULL,
2118 .numpages = numpages,
2119 .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW),
2120 .mask_clr = __pgprot(0),
2121 .flags = 0};
2122
2123 /*
2124 * No alias checking needed for setting present flag. otherwise,
2125 * we may need to break large pages for 64-bit kernel text
2126 * mappings (this adds to complexity if we want to do this from
2127 * atomic context especially). Let's keep it simple!
2128 */
2129 return __change_page_attr_set_clr(&cpa, 0);
2130}
2131
2132static int __set_pages_np(struct page *page, int numpages)
2133{
2134 unsigned long tempaddr = (unsigned long) page_address(page);
2135 struct cpa_data cpa = { .vaddr = &tempaddr,
2136 .pgd = NULL,
2137 .numpages = numpages,
2138 .mask_set = __pgprot(0),
2139 .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
2140 .flags = 0};
2141
2142 /*
2143 * No alias checking needed for setting not present flag. otherwise,
2144 * we may need to break large pages for 64-bit kernel text
2145 * mappings (this adds to complexity if we want to do this from
2146 * atomic context especially). Let's keep it simple!
2147 */
2148 return __change_page_attr_set_clr(&cpa, 0);
2149}
2150
2151int set_direct_map_invalid_noflush(struct page *page)
2152{
2153 return __set_pages_np(page, 1);
2154}
2155
2156int set_direct_map_default_noflush(struct page *page)
2157{
2158 return __set_pages_p(page, 1);
2159}
2160
2161void __kernel_map_pages(struct page *page, int numpages, int enable)
2162{
2163 if (PageHighMem(page))
2164 return;
2165 if (!enable) {
2166 debug_check_no_locks_freed(page_address(page),
2167 numpages * PAGE_SIZE);
2168 }
2169
2170 /*
2171 * The return value is ignored as the calls cannot fail.
2172 * Large pages for identity mappings are not used at boot time
2173 * and hence no memory allocations during large page split.
2174 */
2175 if (enable)
2176 __set_pages_p(page, numpages);
2177 else
2178 __set_pages_np(page, numpages);
2179
2180 /*
2181 * We should perform an IPI and flush all tlbs,
2182 * but that can deadlock->flush only current cpu.
2183 * Preemption needs to be disabled around __flush_tlb_all() due to
2184 * CR3 reload in __native_flush_tlb().
2185 */
2186 preempt_disable();
2187 __flush_tlb_all();
2188 preempt_enable();
2189
2190 arch_flush_lazy_mmu_mode();
2191}
2192
2193#ifdef CONFIG_HIBERNATION
2194bool kernel_page_present(struct page *page)
2195{
2196 unsigned int level;
2197 pte_t *pte;
2198
2199 if (PageHighMem(page))
2200 return false;
2201
2202 pte = lookup_address((unsigned long)page_address(page), &level);
2203 return (pte_val(*pte) & _PAGE_PRESENT);
2204}
2205#endif /* CONFIG_HIBERNATION */
2206
2207int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
2208 unsigned numpages, unsigned long page_flags)
2209{
2210 int retval = -EINVAL;
2211
2212 struct cpa_data cpa = {
2213 .vaddr = &address,
2214 .pfn = pfn,
2215 .pgd = pgd,
2216 .numpages = numpages,
2217 .mask_set = __pgprot(0),
2218 .mask_clr = __pgprot(0),
2219 .flags = 0,
2220 };
2221
2222 WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
2223
2224 if (!(__supported_pte_mask & _PAGE_NX))
2225 goto out;
2226
2227 if (!(page_flags & _PAGE_NX))
2228 cpa.mask_clr = __pgprot(_PAGE_NX);
2229
2230 if (!(page_flags & _PAGE_RW))
2231 cpa.mask_clr = __pgprot(_PAGE_RW);
2232
2233 if (!(page_flags & _PAGE_ENC))
2234 cpa.mask_clr = pgprot_encrypted(cpa.mask_clr);
2235
2236 cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
2237
2238 retval = __change_page_attr_set_clr(&cpa, 0);
2239 __flush_tlb_all();
2240
2241out:
2242 return retval;
2243}
2244
2245/*
2246 * __flush_tlb_all() flushes mappings only on current CPU and hence this
2247 * function shouldn't be used in an SMP environment. Presently, it's used only
2248 * during boot (way before smp_init()) by EFI subsystem and hence is ok.
2249 */
2250int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address,
2251 unsigned long numpages)
2252{
2253 int retval;
2254
2255 /*
2256 * The typical sequence for unmapping is to find a pte through
2257 * lookup_address_in_pgd() (ideally, it should never return NULL because
2258 * the address is already mapped) and change it's protections. As pfn is
2259 * the *target* of a mapping, it's not useful while unmapping.
2260 */
2261 struct cpa_data cpa = {
2262 .vaddr = &address,
2263 .pfn = 0,
2264 .pgd = pgd,
2265 .numpages = numpages,
2266 .mask_set = __pgprot(0),
2267 .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
2268 .flags = 0,
2269 };
2270
2271 WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP");
2272
2273 retval = __change_page_attr_set_clr(&cpa, 0);
2274 __flush_tlb_all();
2275
2276 return retval;
2277}
2278
2279/*
2280 * The testcases use internal knowledge of the implementation that shouldn't
2281 * be exposed to the rest of the kernel. Include these directly here.
2282 */
2283#ifdef CONFIG_CPA_DEBUG
2284#include "pageattr-test.c"
2285#endif