diff options
Diffstat (limited to 'arch/x86/mm/pageattr.c')
| -rw-r--r-- | arch/x86/mm/pageattr.c | 2285 |
1 files changed, 0 insertions, 2285 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c deleted file mode 100644 index 1b99ad05b117..000000000000 --- a/arch/x86/mm/pageattr.c +++ /dev/null @@ -1,2285 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright 2002 Andi Kleen, SuSE Labs. - * Thanks to Ben LaHaise for precious feedback. - */ -#include <linux/highmem.h> -#include <linux/memblock.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/interrupt.h> -#include <linux/seq_file.h> -#include <linux/debugfs.h> -#include <linux/pfn.h> -#include <linux/percpu.h> -#include <linux/gfp.h> -#include <linux/pci.h> -#include <linux/vmalloc.h> - -#include <asm/e820/api.h> -#include <asm/processor.h> -#include <asm/tlbflush.h> -#include <asm/sections.h> -#include <asm/setup.h> -#include <linux/uaccess.h> -#include <asm/pgalloc.h> -#include <asm/proto.h> -#include <asm/pat.h> -#include <asm/set_memory.h> - -#include "mm_internal.h" - -/* - * The current flushing context - we pass it instead of 5 arguments: - */ -struct cpa_data { - unsigned long *vaddr; - pgd_t *pgd; - pgprot_t mask_set; - pgprot_t mask_clr; - unsigned long numpages; - unsigned long curpage; - unsigned long pfn; - unsigned int flags; - unsigned int force_split : 1, - force_static_prot : 1; - struct page **pages; -}; - -enum cpa_warn { - CPA_CONFLICT, - CPA_PROTECT, - CPA_DETECT, -}; - -static const int cpa_warn_level = CPA_PROTECT; - -/* - * Serialize cpa() (for !DEBUG_PAGEALLOC which uses large identity mappings) - * using cpa_lock. So that we don't allow any other cpu, with stale large tlb - * entries change the page attribute in parallel to some other cpu - * splitting a large page entry along with changing the attribute. - */ -static DEFINE_SPINLOCK(cpa_lock); - -#define CPA_FLUSHTLB 1 -#define CPA_ARRAY 2 -#define CPA_PAGES_ARRAY 4 -#define CPA_NO_CHECK_ALIAS 8 /* Do not search for aliases */ - -#ifdef CONFIG_PROC_FS -static unsigned long direct_pages_count[PG_LEVEL_NUM]; - -void update_page_count(int level, unsigned long pages) -{ - /* Protect against CPA */ - spin_lock(&pgd_lock); - direct_pages_count[level] += pages; - spin_unlock(&pgd_lock); -} - -static void split_page_count(int level) -{ - if (direct_pages_count[level] == 0) - return; - - direct_pages_count[level]--; - direct_pages_count[level - 1] += PTRS_PER_PTE; -} - -void arch_report_meminfo(struct seq_file *m) -{ - seq_printf(m, "DirectMap4k: %8lu kB\n", - direct_pages_count[PG_LEVEL_4K] << 2); -#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) - seq_printf(m, "DirectMap2M: %8lu kB\n", - direct_pages_count[PG_LEVEL_2M] << 11); -#else - seq_printf(m, "DirectMap4M: %8lu kB\n", - direct_pages_count[PG_LEVEL_2M] << 12); -#endif - if (direct_gbpages) - seq_printf(m, "DirectMap1G: %8lu kB\n", - direct_pages_count[PG_LEVEL_1G] << 20); -} -#else -static inline void split_page_count(int level) { } -#endif - -#ifdef CONFIG_X86_CPA_STATISTICS - -static unsigned long cpa_1g_checked; -static unsigned long cpa_1g_sameprot; -static unsigned long cpa_1g_preserved; -static unsigned long cpa_2m_checked; -static unsigned long cpa_2m_sameprot; -static unsigned long cpa_2m_preserved; -static unsigned long cpa_4k_install; - -static inline void cpa_inc_1g_checked(void) -{ - cpa_1g_checked++; -} - -static inline void cpa_inc_2m_checked(void) -{ - cpa_2m_checked++; -} - -static inline void cpa_inc_4k_install(void) -{ - cpa_4k_install++; -} - -static inline void cpa_inc_lp_sameprot(int level) -{ - if (level == PG_LEVEL_1G) - cpa_1g_sameprot++; - else - cpa_2m_sameprot++; -} - -static inline void cpa_inc_lp_preserved(int level) -{ - if (level == PG_LEVEL_1G) - cpa_1g_preserved++; - else - cpa_2m_preserved++; -} - -static int cpastats_show(struct seq_file *m, void *p) -{ - seq_printf(m, "1G pages checked: %16lu\n", cpa_1g_checked); - seq_printf(m, "1G pages sameprot: %16lu\n", cpa_1g_sameprot); - seq_printf(m, "1G pages preserved: %16lu\n", cpa_1g_preserved); - seq_printf(m, "2M pages checked: %16lu\n", cpa_2m_checked); - seq_printf(m, "2M pages sameprot: %16lu\n", cpa_2m_sameprot); - seq_printf(m, "2M pages preserved: %16lu\n", cpa_2m_preserved); - seq_printf(m, "4K pages set-checked: %16lu\n", cpa_4k_install); - return 0; -} - -static int cpastats_open(struct inode *inode, struct file *file) -{ - return single_open(file, cpastats_show, NULL); -} - -static const struct file_operations cpastats_fops = { - .open = cpastats_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; - -static int __init cpa_stats_init(void) -{ - debugfs_create_file("cpa_stats", S_IRUSR, arch_debugfs_dir, NULL, - &cpastats_fops); - return 0; -} -late_initcall(cpa_stats_init); -#else -static inline void cpa_inc_1g_checked(void) { } -static inline void cpa_inc_2m_checked(void) { } -static inline void cpa_inc_4k_install(void) { } -static inline void cpa_inc_lp_sameprot(int level) { } -static inline void cpa_inc_lp_preserved(int level) { } -#endif - - -static inline int -within(unsigned long addr, unsigned long start, unsigned long end) -{ - return addr >= start && addr < end; -} - -static inline int -within_inclusive(unsigned long addr, unsigned long start, unsigned long end) -{ - return addr >= start && addr <= end; -} - -#ifdef CONFIG_X86_64 - -static inline unsigned long highmap_start_pfn(void) -{ - return __pa_symbol(_text) >> PAGE_SHIFT; -} - -static inline unsigned long highmap_end_pfn(void) -{ - /* Do not reference physical address outside the kernel. */ - return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT; -} - -static bool __cpa_pfn_in_highmap(unsigned long pfn) -{ - /* - * Kernel text has an alias mapping at a high address, known - * here as "highmap". - */ - return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn()); -} - -#else - -static bool __cpa_pfn_in_highmap(unsigned long pfn) -{ - /* There is no highmap on 32-bit */ - return false; -} - -#endif - -/* - * See set_mce_nospec(). - * - * Machine check recovery code needs to change cache mode of poisoned pages to - * UC to avoid speculative access logging another error. But passing the - * address of the 1:1 mapping to set_memory_uc() is a fine way to encourage a - * speculative access. So we cheat and flip the top bit of the address. This - * works fine for the code that updates the page tables. But at the end of the - * process we need to flush the TLB and cache and the non-canonical address - * causes a #GP fault when used by the INVLPG and CLFLUSH instructions. - * - * But in the common case we already have a canonical address. This code - * will fix the top bit if needed and is a no-op otherwise. - */ -static inline unsigned long fix_addr(unsigned long addr) -{ -#ifdef CONFIG_X86_64 - return (long)(addr << 1) >> 1; -#else - return addr; -#endif -} - -static unsigned long __cpa_addr(struct cpa_data *cpa, unsigned long idx) -{ - if (cpa->flags & CPA_PAGES_ARRAY) { - struct page *page = cpa->pages[idx]; - - if (unlikely(PageHighMem(page))) - return 0; - - return (unsigned long)page_address(page); - } - - if (cpa->flags & CPA_ARRAY) - return cpa->vaddr[idx]; - - return *cpa->vaddr + idx * PAGE_SIZE; -} - -/* - * Flushing functions - */ - -static void clflush_cache_range_opt(void *vaddr, unsigned int size) -{ - const unsigned long clflush_size = boot_cpu_data.x86_clflush_size; - void *p = (void *)((unsigned long)vaddr & ~(clflush_size - 1)); - void *vend = vaddr + size; - - if (p >= vend) - return; - - for (; p < vend; p += clflush_size) - clflushopt(p); -} - -/** - * clflush_cache_range - flush a cache range with clflush - * @vaddr: virtual start address - * @size: number of bytes to flush - * - * CLFLUSHOPT is an unordered instruction which needs fencing with MFENCE or - * SFENCE to avoid ordering issues. - */ -void clflush_cache_range(void *vaddr, unsigned int size) -{ - mb(); - clflush_cache_range_opt(vaddr, size); - mb(); -} -EXPORT_SYMBOL_GPL(clflush_cache_range); - -void arch_invalidate_pmem(void *addr, size_t size) -{ - clflush_cache_range(addr, size); -} -EXPORT_SYMBOL_GPL(arch_invalidate_pmem); - -static void __cpa_flush_all(void *arg) -{ - unsigned long cache = (unsigned long)arg; - - /* - * Flush all to work around Errata in early athlons regarding - * large page flushing. - */ - __flush_tlb_all(); - - if (cache && boot_cpu_data.x86 >= 4) - wbinvd(); -} - -static void cpa_flush_all(unsigned long cache) -{ - BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); - - on_each_cpu(__cpa_flush_all, (void *) cache, 1); -} - -void __cpa_flush_tlb(void *data) -{ - struct cpa_data *cpa = data; - unsigned int i; - - for (i = 0; i < cpa->numpages; i++) - __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i))); -} - -static void cpa_flush(struct cpa_data *data, int cache) -{ - struct cpa_data *cpa = data; - unsigned int i; - - BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); - - if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) { - cpa_flush_all(cache); - return; - } - - if (cpa->numpages <= tlb_single_page_flush_ceiling) - on_each_cpu(__cpa_flush_tlb, cpa, 1); - else - flush_tlb_all(); - - if (!cache) - return; - - mb(); - for (i = 0; i < cpa->numpages; i++) { - unsigned long addr = __cpa_addr(cpa, i); - unsigned int level; - - pte_t *pte = lookup_address(addr, &level); - - /* - * Only flush present addresses: - */ - if (pte && (pte_val(*pte) & _PAGE_PRESENT)) - clflush_cache_range_opt((void *)fix_addr(addr), PAGE_SIZE); - } - mb(); -} - -static bool overlaps(unsigned long r1_start, unsigned long r1_end, - unsigned long r2_start, unsigned long r2_end) -{ - return (r1_start <= r2_end && r1_end >= r2_start) || - (r2_start <= r1_end && r2_end >= r1_start); -} - -#ifdef CONFIG_PCI_BIOS -/* - * The BIOS area between 640k and 1Mb needs to be executable for PCI BIOS - * based config access (CONFIG_PCI_GOBIOS) support. - */ -#define BIOS_PFN PFN_DOWN(BIOS_BEGIN) -#define BIOS_PFN_END PFN_DOWN(BIOS_END - 1) - -static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn) -{ - if (pcibios_enabled && overlaps(spfn, epfn, BIOS_PFN, BIOS_PFN_END)) - return _PAGE_NX; - return 0; -} -#else -static pgprotval_t protect_pci_bios(unsigned long spfn, unsigned long epfn) -{ - return 0; -} -#endif - -/* - * The .rodata section needs to be read-only. Using the pfn catches all - * aliases. This also includes __ro_after_init, so do not enforce until - * kernel_set_to_readonly is true. - */ -static pgprotval_t protect_rodata(unsigned long spfn, unsigned long epfn) -{ - unsigned long epfn_ro, spfn_ro = PFN_DOWN(__pa_symbol(__start_rodata)); - - /* - * Note: __end_rodata is at page aligned and not inclusive, so - * subtract 1 to get the last enforced PFN in the rodata area. - */ - epfn_ro = PFN_DOWN(__pa_symbol(__end_rodata)) - 1; - - if (kernel_set_to_readonly && overlaps(spfn, epfn, spfn_ro, epfn_ro)) - return _PAGE_RW; - return 0; -} - -/* - * Protect kernel text against becoming non executable by forbidding - * _PAGE_NX. This protects only the high kernel mapping (_text -> _etext) - * out of which the kernel actually executes. Do not protect the low - * mapping. - * - * This does not cover __inittext since that is gone after boot. - */ -static pgprotval_t protect_kernel_text(unsigned long start, unsigned long end) -{ - unsigned long t_end = (unsigned long)_etext - 1; - unsigned long t_start = (unsigned long)_text; - - if (overlaps(start, end, t_start, t_end)) - return _PAGE_NX; - return 0; -} - -#if defined(CONFIG_X86_64) -/* - * Once the kernel maps the text as RO (kernel_set_to_readonly is set), - * kernel text mappings for the large page aligned text, rodata sections - * will be always read-only. For the kernel identity mappings covering the - * holes caused by this alignment can be anything that user asks. - * - * This will preserve the large page mappings for kernel text/data at no - * extra cost. - */ -static pgprotval_t protect_kernel_text_ro(unsigned long start, - unsigned long end) -{ - unsigned long t_end = (unsigned long)__end_rodata_hpage_align - 1; - unsigned long t_start = (unsigned long)_text; - unsigned int level; - - if (!kernel_set_to_readonly || !overlaps(start, end, t_start, t_end)) - return 0; - /* - * Don't enforce the !RW mapping for the kernel text mapping, if - * the current mapping is already using small page mapping. No - * need to work hard to preserve large page mappings in this case. - * - * This also fixes the Linux Xen paravirt guest boot failure caused - * by unexpected read-only mappings for kernel identity - * mappings. In this paravirt guest case, the kernel text mapping - * and the kernel identity mapping share the same page-table pages, - * so the protections for kernel text and identity mappings have to - * be the same. - */ - if (lookup_address(start, &level) && (level != PG_LEVEL_4K)) - return _PAGE_RW; - return 0; -} -#else -static pgprotval_t protect_kernel_text_ro(unsigned long start, - unsigned long end) -{ - return 0; -} -#endif - -static inline bool conflicts(pgprot_t prot, pgprotval_t val) -{ - return (pgprot_val(prot) & ~val) != pgprot_val(prot); -} - -static inline void check_conflict(int warnlvl, pgprot_t prot, pgprotval_t val, - unsigned long start, unsigned long end, - unsigned long pfn, const char *txt) -{ - static const char *lvltxt[] = { - [CPA_CONFLICT] = "conflict", - [CPA_PROTECT] = "protect", - [CPA_DETECT] = "detect", - }; - - if (warnlvl > cpa_warn_level || !conflicts(prot, val)) - return; - - pr_warn("CPA %8s %10s: 0x%016lx - 0x%016lx PFN %lx req %016llx prevent %016llx\n", - lvltxt[warnlvl], txt, start, end, pfn, (unsigned long long)pgprot_val(prot), - (unsigned long long)val); -} - -/* - * Certain areas of memory on x86 require very specific protection flags, - * for example the BIOS area or kernel text. Callers don't always get this - * right (again, ioremap() on BIOS memory is not uncommon) so this function - * checks and fixes these known static required protection bits. - */ -static inline pgprot_t static_protections(pgprot_t prot, unsigned long start, - unsigned long pfn, unsigned long npg, - unsigned long lpsize, int warnlvl) -{ - pgprotval_t forbidden, res; - unsigned long end; - - /* - * There is no point in checking RW/NX conflicts when the requested - * mapping is setting the page !PRESENT. - */ - if (!(pgprot_val(prot) & _PAGE_PRESENT)) - return prot; - - /* Operate on the virtual address */ - end = start + npg * PAGE_SIZE - 1; - - res = protect_kernel_text(start, end); - check_conflict(warnlvl, prot, res, start, end, pfn, "Text NX"); - forbidden = res; - - /* - * Special case to preserve a large page. If the change spawns the - * full large page mapping then there is no point to split it - * up. Happens with ftrace and is going to be removed once ftrace - * switched to text_poke(). - */ - if (lpsize != (npg * PAGE_SIZE) || (start & (lpsize - 1))) { - res = protect_kernel_text_ro(start, end); - check_conflict(warnlvl, prot, res, start, end, pfn, "Text RO"); - forbidden |= res; - } - - /* Check the PFN directly */ - res = protect_pci_bios(pfn, pfn + npg - 1); - check_conflict(warnlvl, prot, res, start, end, pfn, "PCIBIOS NX"); - forbidden |= res; - - res = protect_rodata(pfn, pfn + npg - 1); - check_conflict(warnlvl, prot, res, start, end, pfn, "Rodata RO"); - forbidden |= res; - - return __pgprot(pgprot_val(prot) & ~forbidden); -} - -/* - * Lookup the page table entry for a virtual address in a specific pgd. - * Return a pointer to the entry and the level of the mapping. - */ -pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, - unsigned int *level) -{ - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - - *level = PG_LEVEL_NONE; - - if (pgd_none(*pgd)) - return NULL; - - p4d = p4d_offset(pgd, address); - if (p4d_none(*p4d)) - return NULL; - - *level = PG_LEVEL_512G; - if (p4d_large(*p4d) || !p4d_present(*p4d)) - return (pte_t *)p4d; - - pud = pud_offset(p4d, address); - if (pud_none(*pud)) - return NULL; - - *level = PG_LEVEL_1G; - if (pud_large(*pud) || !pud_present(*pud)) - return (pte_t *)pud; - - pmd = pmd_offset(pud, address); - if (pmd_none(*pmd)) - return NULL; - - *level = PG_LEVEL_2M; - if (pmd_large(*pmd) || !pmd_present(*pmd)) - return (pte_t *)pmd; - - *level = PG_LEVEL_4K; - - return pte_offset_kernel(pmd, address); -} - -/* - * Lookup the page table entry for a virtual address. Return a pointer - * to the entry and the level of the mapping. - * - * Note: We return pud and pmd either when the entry is marked large - * or when the present bit is not set. Otherwise we would return a - * pointer to a nonexisting mapping. - */ -pte_t *lookup_address(unsigned long address, unsigned int *level) -{ - return lookup_address_in_pgd(pgd_offset_k(address), address, level); -} -EXPORT_SYMBOL_GPL(lookup_address); - -static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address, - unsigned int *level) -{ - if (cpa->pgd) - return lookup_address_in_pgd(cpa->pgd + pgd_index(address), - address, level); - - return lookup_address(address, level); -} - -/* - * Lookup the PMD entry for a virtual address. Return a pointer to the entry - * or NULL if not present. - */ -pmd_t *lookup_pmd_address(unsigned long address) -{ - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - - pgd = pgd_offset_k(address); - if (pgd_none(*pgd)) - return NULL; - - p4d = p4d_offset(pgd, address); - if (p4d_none(*p4d) || p4d_large(*p4d) || !p4d_present(*p4d)) - return NULL; - - pud = pud_offset(p4d, address); - if (pud_none(*pud) || pud_large(*pud) || !pud_present(*pud)) - return NULL; - - return pmd_offset(pud, address); -} - -/* - * This is necessary because __pa() does not work on some - * kinds of memory, like vmalloc() or the alloc_remap() - * areas on 32-bit NUMA systems. The percpu areas can - * end up in this kind of memory, for instance. - * - * This could be optimized, but it is only intended to be - * used at inititalization time, and keeping it - * unoptimized should increase the testing coverage for - * the more obscure platforms. - */ -phys_addr_t slow_virt_to_phys(void *__virt_addr) -{ - unsigned long virt_addr = (unsigned long)__virt_addr; - phys_addr_t phys_addr; - unsigned long offset; - enum pg_level level; - pte_t *pte; - - pte = lookup_address(virt_addr, &level); - BUG_ON(!pte); - - /* - * pXX_pfn() returns unsigned long, which must be cast to phys_addr_t - * before being left-shifted PAGE_SHIFT bits -- this trick is to - * make 32-PAE kernel work correctly. - */ - switch (level) { - case PG_LEVEL_1G: - phys_addr = (phys_addr_t)pud_pfn(*(pud_t *)pte) << PAGE_SHIFT; - offset = virt_addr & ~PUD_PAGE_MASK; - break; - case PG_LEVEL_2M: - phys_addr = (phys_addr_t)pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT; - offset = virt_addr & ~PMD_PAGE_MASK; - break; - default: - phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT; - offset = virt_addr & ~PAGE_MASK; - } - - return (phys_addr_t)(phys_addr | offset); -} -EXPORT_SYMBOL_GPL(slow_virt_to_phys); - -/* - * Set the new pmd in all the pgds we know about: - */ -static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte) -{ - /* change init_mm */ - set_pte_atomic(kpte, pte); -#ifdef CONFIG_X86_32 - if (!SHARED_KERNEL_PMD) { - struct page *page; - - list_for_each_entry(page, &pgd_list, lru) { - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - - pgd = (pgd_t *)page_address(page) + pgd_index(address); - p4d = p4d_offset(pgd, address); - pud = pud_offset(p4d, address); - pmd = pmd_offset(pud, address); - set_pte_atomic((pte_t *)pmd, pte); - } - } -#endif -} - -static pgprot_t pgprot_clear_protnone_bits(pgprot_t prot) -{ - /* - * _PAGE_GLOBAL means "global page" for present PTEs. - * But, it is also used to indicate _PAGE_PROTNONE - * for non-present PTEs. - * - * This ensures that a _PAGE_GLOBAL PTE going from - * present to non-present is not confused as - * _PAGE_PROTNONE. - */ - if (!(pgprot_val(prot) & _PAGE_PRESENT)) - pgprot_val(prot) &= ~_PAGE_GLOBAL; - - return prot; -} - -static int __should_split_large_page(pte_t *kpte, unsigned long address, - struct cpa_data *cpa) -{ - unsigned long numpages, pmask, psize, lpaddr, pfn, old_pfn; - pgprot_t old_prot, new_prot, req_prot, chk_prot; - pte_t new_pte, *tmp; - enum pg_level level; - - /* - * Check for races, another CPU might have split this page - * up already: - */ - tmp = _lookup_address_cpa(cpa, address, &level); - if (tmp != kpte) - return 1; - - switch (level) { - case PG_LEVEL_2M: - old_prot = pmd_pgprot(*(pmd_t *)kpte); - old_pfn = pmd_pfn(*(pmd_t *)kpte); - cpa_inc_2m_checked(); - break; - case PG_LEVEL_1G: - old_prot = pud_pgprot(*(pud_t *)kpte); - old_pfn = pud_pfn(*(pud_t *)kpte); - cpa_inc_1g_checked(); - break; - default: - return -EINVAL; - } - - psize = page_level_size(level); - pmask = page_level_mask(level); - - /* - * Calculate the number of pages, which fit into this large - * page starting at address: - */ - lpaddr = (address + psize) & pmask; - numpages = (lpaddr - address) >> PAGE_SHIFT; - if (numpages < cpa->numpages) - cpa->numpages = numpages; - - /* - * We are safe now. Check whether the new pgprot is the same: - * Convert protection attributes to 4k-format, as cpa->mask* are set - * up accordingly. - */ - - /* Clear PSE (aka _PAGE_PAT) and move PAT bit to correct position */ - req_prot = pgprot_large_2_4k(old_prot); - - pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr); - pgprot_val(req_prot) |= pgprot_val(cpa->mask_set); - - /* - * req_prot is in format of 4k pages. It must be converted to large - * page format: the caching mode includes the PAT bit located at - * different bit positions in the two formats. - */ - req_prot = pgprot_4k_2_large(req_prot); - req_prot = pgprot_clear_protnone_bits(req_prot); - if (pgprot_val(req_prot) & _PAGE_PRESENT) - pgprot_val(req_prot) |= _PAGE_PSE; - - /* - * old_pfn points to the large page base pfn. So we need to add the - * offset of the virtual address: - */ - pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT); - cpa->pfn = pfn; - - /* - * Calculate the large page base address and the number of 4K pages - * in the large page - */ - lpaddr = address & pmask; - numpages = psize >> PAGE_SHIFT; - - /* - * Sanity check that the existing mapping is correct versus the static - * protections. static_protections() guards against !PRESENT, so no - * extra conditional required here. - */ - chk_prot = static_protections(old_prot, lpaddr, old_pfn, numpages, - psize, CPA_CONFLICT); - - if (WARN_ON_ONCE(pgprot_val(chk_prot) != pgprot_val(old_prot))) { - /* - * Split the large page and tell the split code to - * enforce static protections. - */ - cpa->force_static_prot = 1; - return 1; - } - - /* - * Optimization: If the requested pgprot is the same as the current - * pgprot, then the large page can be preserved and no updates are - * required independent of alignment and length of the requested - * range. The above already established that the current pgprot is - * correct, which in consequence makes the requested pgprot correct - * as well if it is the same. The static protection scan below will - * not come to a different conclusion. - */ - if (pgprot_val(req_prot) == pgprot_val(old_prot)) { - cpa_inc_lp_sameprot(level); - return 0; - } - - /* - * If the requested range does not cover the full page, split it up - */ - if (address != lpaddr || cpa->numpages != numpages) - return 1; - - /* - * Check whether the requested pgprot is conflicting with a static - * protection requirement in the large page. - */ - new_prot = static_protections(req_prot, lpaddr, old_pfn, numpages, - psize, CPA_DETECT); - - /* - * If there is a conflict, split the large page. - * - * There used to be a 4k wise evaluation trying really hard to - * preserve the large pages, but experimentation has shown, that this - * does not help at all. There might be corner cases which would - * preserve one large page occasionally, but it's really not worth the - * extra code and cycles for the common case. - */ - if (pgprot_val(req_prot) != pgprot_val(new_prot)) - return 1; - - /* All checks passed. Update the large page mapping. */ - new_pte = pfn_pte(old_pfn, new_prot); - __set_pmd_pte(kpte, address, new_pte); - cpa->flags |= CPA_FLUSHTLB; - cpa_inc_lp_preserved(level); - return 0; -} - -static int should_split_large_page(pte_t *kpte, unsigned long address, - struct cpa_data *cpa) -{ - int do_split; - - if (cpa->force_split) - return 1; - - spin_lock(&pgd_lock); - do_split = __should_split_large_page(kpte, address, cpa); - spin_unlock(&pgd_lock); - - return do_split; -} - -static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn, - pgprot_t ref_prot, unsigned long address, - unsigned long size) -{ - unsigned int npg = PFN_DOWN(size); - pgprot_t prot; - - /* - * If should_split_large_page() discovered an inconsistent mapping, - * remove the invalid protection in the split mapping. - */ - if (!cpa->force_static_prot) - goto set; - - /* Hand in lpsize = 0 to enforce the protection mechanism */ - prot = static_protections(ref_prot, address, pfn, npg, 0, CPA_PROTECT); - - if (pgprot_val(prot) == pgprot_val(ref_prot)) - goto set; - - /* - * If this is splitting a PMD, fix it up. PUD splits cannot be - * fixed trivially as that would require to rescan the newly - * installed PMD mappings after returning from split_large_page() - * so an eventual further split can allocate the necessary PTE - * pages. Warn for now and revisit it in case this actually - * happens. - */ - if (size == PAGE_SIZE) - ref_prot = prot; - else - pr_warn_once("CPA: Cannot fixup static protections for PUD split\n"); -set: - set_pte(pte, pfn_pte(pfn, ref_prot)); -} - -static int -__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address, - struct page *base) -{ - unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1; - pte_t *pbase = (pte_t *)page_address(base); - unsigned int i, level; - pgprot_t ref_prot; - pte_t *tmp; - - spin_lock(&pgd_lock); - /* - * Check for races, another CPU might have split this page - * up for us already: - */ - tmp = _lookup_address_cpa(cpa, address, &level); - if (tmp != kpte) { - spin_unlock(&pgd_lock); - return 1; - } - - paravirt_alloc_pte(&init_mm, page_to_pfn(base)); - - switch (level) { - case PG_LEVEL_2M: - ref_prot = pmd_pgprot(*(pmd_t *)kpte); - /* - * Clear PSE (aka _PAGE_PAT) and move - * PAT bit to correct position. - */ - ref_prot = pgprot_large_2_4k(ref_prot); - ref_pfn = pmd_pfn(*(pmd_t *)kpte); - lpaddr = address & PMD_MASK; - lpinc = PAGE_SIZE; - break; - - case PG_LEVEL_1G: - ref_prot = pud_pgprot(*(pud_t *)kpte); - ref_pfn = pud_pfn(*(pud_t *)kpte); - pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT; - lpaddr = address & PUD_MASK; - lpinc = PMD_SIZE; - /* - * Clear the PSE flags if the PRESENT flag is not set - * otherwise pmd_present/pmd_huge will return true - * even on a non present pmd. - */ - if (!(pgprot_val(ref_prot) & _PAGE_PRESENT)) - pgprot_val(ref_prot) &= ~_PAGE_PSE; - break; - - default: - spin_unlock(&pgd_lock); - return 1; - } - - ref_prot = pgprot_clear_protnone_bits(ref_prot); - - /* - * Get the target pfn from the original entry: - */ - pfn = ref_pfn; - for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc, lpaddr += lpinc) - split_set_pte(cpa, pbase + i, pfn, ref_prot, lpaddr, lpinc); - - if (virt_addr_valid(address)) { - unsigned long pfn = PFN_DOWN(__pa(address)); - - if (pfn_range_is_mapped(pfn, pfn + 1)) - split_page_count(level); - } - - /* - * Install the new, split up pagetable. - * - * We use the standard kernel pagetable protections for the new - * pagetable protections, the actual ptes set above control the - * primary protection behavior: - */ - __set_pmd_pte(kpte, address, mk_pte(base, __pgprot(_KERNPG_TABLE))); - - /* - * Do a global flush tlb after splitting the large page - * and before we do the actual change page attribute in the PTE. - * - * Without this, we violate the TLB application note, that says: - * "The TLBs may contain both ordinary and large-page - * translations for a 4-KByte range of linear addresses. This - * may occur if software modifies the paging structures so that - * the page size used for the address range changes. If the two - * translations differ with respect to page frame or attributes - * (e.g., permissions), processor behavior is undefined and may - * be implementation-specific." - * - * We do this global tlb flush inside the cpa_lock, so that we - * don't allow any other cpu, with stale tlb entries change the - * page attribute in parallel, that also falls into the - * just split large page entry. - */ - flush_tlb_all(); - spin_unlock(&pgd_lock); - - return 0; -} - -static int split_large_page(struct cpa_data *cpa, pte_t *kpte, - unsigned long address) -{ - struct page *base; - - if (!debug_pagealloc_enabled()) - spin_unlock(&cpa_lock); - base = alloc_pages(GFP_KERNEL, 0); - if (!debug_pagealloc_enabled()) - spin_lock(&cpa_lock); - if (!base) - return -ENOMEM; - - if (__split_large_page(cpa, kpte, address, base)) - __free_page(base); - - return 0; -} - -static bool try_to_free_pte_page(pte_t *pte) -{ - int i; - - for (i = 0; i < PTRS_PER_PTE; i++) - if (!pte_none(pte[i])) - return false; - - free_page((unsigned long)pte); - return true; -} - -static bool try_to_free_pmd_page(pmd_t *pmd) -{ - int i; - - for (i = 0; i < PTRS_PER_PMD; i++) - if (!pmd_none(pmd[i])) - return false; - - free_page((unsigned long)pmd); - return true; -} - -static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end) -{ - pte_t *pte = pte_offset_kernel(pmd, start); - - while (start < end) { - set_pte(pte, __pte(0)); - - start += PAGE_SIZE; - pte++; - } - - if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) { - pmd_clear(pmd); - return true; - } - return false; -} - -static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd, - unsigned long start, unsigned long end) -{ - if (unmap_pte_range(pmd, start, end)) - if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud))) - pud_clear(pud); -} - -static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end) -{ - pmd_t *pmd = pmd_offset(pud, start); - - /* - * Not on a 2MB page boundary? - */ - if (start & (PMD_SIZE - 1)) { - unsigned long next_page = (start + PMD_SIZE) & PMD_MASK; - unsigned long pre_end = min_t(unsigned long, end, next_page); - - __unmap_pmd_range(pud, pmd, start, pre_end); - - start = pre_end; - pmd++; - } - - /* - * Try to unmap in 2M chunks. - */ - while (end - start >= PMD_SIZE) { - if (pmd_large(*pmd)) - pmd_clear(pmd); - else - __unmap_pmd_range(pud, pmd, start, start + PMD_SIZE); - - start += PMD_SIZE; - pmd++; - } - - /* - * 4K leftovers? - */ - if (start < end) - return __unmap_pmd_range(pud, pmd, start, end); - - /* - * Try again to free the PMD page if haven't succeeded above. - */ - if (!pud_none(*pud)) - if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud))) - pud_clear(pud); -} - -static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end) -{ - pud_t *pud = pud_offset(p4d, start); - - /* - * Not on a GB page boundary? - */ - if (start & (PUD_SIZE - 1)) { - unsigned long next_page = (start + PUD_SIZE) & PUD_MASK; - unsigned long pre_end = min_t(unsigned long, end, next_page); - - unmap_pmd_range(pud, start, pre_end); - - start = pre_end; - pud++; - } - - /* - * Try to unmap in 1G chunks? - */ - while (end - start >= PUD_SIZE) { - - if (pud_large(*pud)) - pud_clear(pud); - else - unmap_pmd_range(pud, start, start + PUD_SIZE); - - start += PUD_SIZE; - pud++; - } - - /* - * 2M leftovers? - */ - if (start < end) - unmap_pmd_range(pud, start, end); - - /* - * No need to try to free the PUD page because we'll free it in - * populate_pgd's error path - */ -} - -static int alloc_pte_page(pmd_t *pmd) -{ - pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL); - if (!pte) - return -1; - - set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE)); - return 0; -} - -static int alloc_pmd_page(pud_t *pud) -{ - pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL); - if (!pmd) - return -1; - - set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); - return 0; -} - -static void populate_pte(struct cpa_data *cpa, - unsigned long start, unsigned long end, - unsigned num_pages, pmd_t *pmd, pgprot_t pgprot) -{ - pte_t *pte; - - pte = pte_offset_kernel(pmd, start); - - pgprot = pgprot_clear_protnone_bits(pgprot); - - while (num_pages-- && start < end) { - set_pte(pte, pfn_pte(cpa->pfn, pgprot)); - - start += PAGE_SIZE; - cpa->pfn++; - pte++; - } -} - -static long populate_pmd(struct cpa_data *cpa, - unsigned long start, unsigned long end, - unsigned num_pages, pud_t *pud, pgprot_t pgprot) -{ - long cur_pages = 0; - pmd_t *pmd; - pgprot_t pmd_pgprot; - - /* - * Not on a 2M boundary? - */ - if (start & (PMD_SIZE - 1)) { - unsigned long pre_end = start + (num_pages << PAGE_SHIFT); - unsigned long next_page = (start + PMD_SIZE) & PMD_MASK; - - pre_end = min_t(unsigned long, pre_end, next_page); - cur_pages = (pre_end - start) >> PAGE_SHIFT; - cur_pages = min_t(unsigned int, num_pages, cur_pages); - - /* - * Need a PTE page? - */ - pmd = pmd_offset(pud, start); - if (pmd_none(*pmd)) - if (alloc_pte_page(pmd)) - return -1; - - populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot); - - start = pre_end; - } - - /* - * We mapped them all? - */ - if (num_pages == cur_pages) - return cur_pages; - - pmd_pgprot = pgprot_4k_2_large(pgprot); - - while (end - start >= PMD_SIZE) { - - /* - * We cannot use a 1G page so allocate a PMD page if needed. - */ - if (pud_none(*pud)) - if (alloc_pmd_page(pud)) - return -1; - - pmd = pmd_offset(pud, start); - - set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn, - canon_pgprot(pmd_pgprot)))); - - start += PMD_SIZE; - cpa->pfn += PMD_SIZE >> PAGE_SHIFT; - cur_pages += PMD_SIZE >> PAGE_SHIFT; - } - - /* - * Map trailing 4K pages. - */ - if (start < end) { - pmd = pmd_offset(pud, start); - if (pmd_none(*pmd)) - if (alloc_pte_page(pmd)) - return -1; - - populate_pte(cpa, start, end, num_pages - cur_pages, - pmd, pgprot); - } - return num_pages; -} - -static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d, - pgprot_t pgprot) -{ - pud_t *pud; - unsigned long end; - long cur_pages = 0; - pgprot_t pud_pgprot; - - end = start + (cpa->numpages << PAGE_SHIFT); - - /* - * Not on a Gb page boundary? => map everything up to it with - * smaller pages. - */ - if (start & (PUD_SIZE - 1)) { - unsigned long pre_end; - unsigned long next_page = (start + PUD_SIZE) & PUD_MASK; - - pre_end = min_t(unsigned long, end, next_page); - cur_pages = (pre_end - start) >> PAGE_SHIFT; - cur_pages = min_t(int, (int)cpa->numpages, cur_pages); - - pud = pud_offset(p4d, start); - - /* - * Need a PMD page? - */ - if (pud_none(*pud)) - if (alloc_pmd_page(pud)) - return -1; - - cur_pages = populate_pmd(cpa, start, pre_end, cur_pages, - pud, pgprot); - if (cur_pages < 0) - return cur_pages; - - start = pre_end; - } - - /* We mapped them all? */ - if (cpa->numpages == cur_pages) - return cur_pages; - - pud = pud_offset(p4d, start); - pud_pgprot = pgprot_4k_2_large(pgprot); - - /* - * Map everything starting from the Gb boundary, possibly with 1G pages - */ - while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) { - set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn, - canon_pgprot(pud_pgprot)))); - - start += PUD_SIZE; - cpa->pfn += PUD_SIZE >> PAGE_SHIFT; - cur_pages += PUD_SIZE >> PAGE_SHIFT; - pud++; - } - - /* Map trailing leftover */ - if (start < end) { - long tmp; - - pud = pud_offset(p4d, start); - if (pud_none(*pud)) - if (alloc_pmd_page(pud)) - return -1; - - tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages, - pud, pgprot); - if (tmp < 0) - return cur_pages; - - cur_pages += tmp; - } - return cur_pages; -} - -/* - * Restrictions for kernel page table do not necessarily apply when mapping in - * an alternate PGD. - */ -static int populate_pgd(struct cpa_data *cpa, unsigned long addr) -{ - pgprot_t pgprot = __pgprot(_KERNPG_TABLE); - pud_t *pud = NULL; /* shut up gcc */ - p4d_t *p4d; - pgd_t *pgd_entry; - long ret; - - pgd_entry = cpa->pgd + pgd_index(addr); - - if (pgd_none(*pgd_entry)) { - p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL); - if (!p4d) - return -1; - - set_pgd(pgd_entry, __pgd(__pa(p4d) | _KERNPG_TABLE)); - } - - /* - * Allocate a PUD page and hand it down for mapping. - */ - p4d = p4d_offset(pgd_entry, addr); - if (p4d_none(*p4d)) { - pud = (pud_t *)get_zeroed_page(GFP_KERNEL); - if (!pud) - return -1; - - set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE)); - } - - pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr); - pgprot_val(pgprot) |= pgprot_val(cpa->mask_set); - - ret = populate_pud(cpa, addr, p4d, pgprot); - if (ret < 0) { - /* - * Leave the PUD page in place in case some other CPU or thread - * already found it, but remove any useless entries we just - * added to it. - */ - unmap_pud_range(p4d, addr, - addr + (cpa->numpages << PAGE_SHIFT)); - return ret; - } - - cpa->numpages = ret; - return 0; -} - -static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr, - int primary) -{ - if (cpa->pgd) { - /* - * Right now, we only execute this code path when mapping - * the EFI virtual memory map regions, no other users - * provide a ->pgd value. This may change in the future. - */ - return populate_pgd(cpa, vaddr); - } - - /* - * Ignore all non primary paths. - */ - if (!primary) { - cpa->numpages = 1; - return 0; - } - - /* - * Ignore the NULL PTE for kernel identity mapping, as it is expected - * to have holes. - * Also set numpages to '1' indicating that we processed cpa req for - * one virtual address page and its pfn. TBD: numpages can be set based - * on the initial value and the level returned by lookup_address(). - */ - if (within(vaddr, PAGE_OFFSET, - PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) { - cpa->numpages = 1; - cpa->pfn = __pa(vaddr) >> PAGE_SHIFT; - return 0; - - } else if (__cpa_pfn_in_highmap(cpa->pfn)) { - /* Faults in the highmap are OK, so do not warn: */ - return -EFAULT; - } else { - WARN(1, KERN_WARNING "CPA: called for zero pte. " - "vaddr = %lx cpa->vaddr = %lx\n", vaddr, - *cpa->vaddr); - - return -EFAULT; - } -} - -static int __change_page_attr(struct cpa_data *cpa, int primary) -{ - unsigned long address; - int do_split, err; - unsigned int level; - pte_t *kpte, old_pte; - - address = __cpa_addr(cpa, cpa->curpage); -repeat: - kpte = _lookup_address_cpa(cpa, address, &level); - if (!kpte) - return __cpa_process_fault(cpa, address, primary); - - old_pte = *kpte; - if (pte_none(old_pte)) - return __cpa_process_fault(cpa, address, primary); - - if (level == PG_LEVEL_4K) { - pte_t new_pte; - pgprot_t new_prot = pte_pgprot(old_pte); - unsigned long pfn = pte_pfn(old_pte); - - pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr); - pgprot_val(new_prot) |= pgprot_val(cpa->mask_set); - - cpa_inc_4k_install(); - /* Hand in lpsize = 0 to enforce the protection mechanism */ - new_prot = static_protections(new_prot, address, pfn, 1, 0, - CPA_PROTECT); - - new_prot = pgprot_clear_protnone_bits(new_prot); - - /* - * We need to keep the pfn from the existing PTE, - * after all we're only going to change it's attributes - * not the memory it points to - */ - new_pte = pfn_pte(pfn, new_prot); - cpa->pfn = pfn; - /* - * Do we really change anything ? - */ - if (pte_val(old_pte) != pte_val(new_pte)) { - set_pte_atomic(kpte, new_pte); - cpa->flags |= CPA_FLUSHTLB; - } - cpa->numpages = 1; - return 0; - } - - /* - * Check, whether we can keep the large page intact - * and just change the pte: - */ - do_split = should_split_large_page(kpte, address, cpa); - /* - * When the range fits into the existing large page, - * return. cp->numpages and cpa->tlbflush have been updated in - * try_large_page: - */ - if (do_split <= 0) - return do_split; - - /* - * We have to split the large page: - */ - err = split_large_page(cpa, kpte, address); - if (!err) - goto repeat; - - return err; -} - -static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias); - -static int cpa_process_alias(struct cpa_data *cpa) -{ - struct cpa_data alias_cpa; - unsigned long laddr = (unsigned long)__va(cpa->pfn << PAGE_SHIFT); - unsigned long vaddr; - int ret; - - if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1)) - return 0; - - /* - * No need to redo, when the primary call touched the direct - * mapping already: - */ - vaddr = __cpa_addr(cpa, cpa->curpage); - if (!(within(vaddr, PAGE_OFFSET, - PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)))) { - - alias_cpa = *cpa; - alias_cpa.vaddr = &laddr; - alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); - alias_cpa.curpage = 0; - - ret = __change_page_attr_set_clr(&alias_cpa, 0); - if (ret) - return ret; - } - -#ifdef CONFIG_X86_64 - /* - * If the primary call didn't touch the high mapping already - * and the physical address is inside the kernel map, we need - * to touch the high mapped kernel as well: - */ - if (!within(vaddr, (unsigned long)_text, _brk_end) && - __cpa_pfn_in_highmap(cpa->pfn)) { - unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) + - __START_KERNEL_map - phys_base; - alias_cpa = *cpa; - alias_cpa.vaddr = &temp_cpa_vaddr; - alias_cpa.flags &= ~(CPA_PAGES_ARRAY | CPA_ARRAY); - alias_cpa.curpage = 0; - - /* - * The high mapping range is imprecise, so ignore the - * return value. - */ - __change_page_attr_set_clr(&alias_cpa, 0); - } -#endif - - return 0; -} - -static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) -{ - unsigned long numpages = cpa->numpages; - unsigned long rempages = numpages; - int ret = 0; - - while (rempages) { - /* - * Store the remaining nr of pages for the large page - * preservation check. - */ - cpa->numpages = rempages; - /* for array changes, we can't use large page */ - if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY)) - cpa->numpages = 1; - - if (!debug_pagealloc_enabled()) - spin_lock(&cpa_lock); - ret = __change_page_attr(cpa, checkalias); - if (!debug_pagealloc_enabled()) - spin_unlock(&cpa_lock); - if (ret) - goto out; - - if (checkalias) { - ret = cpa_process_alias(cpa); - if (ret) - goto out; - } - - /* - * Adjust the number of pages with the result of the - * CPA operation. Either a large page has been - * preserved or a single page update happened. - */ - BUG_ON(cpa->numpages > rempages || !cpa->numpages); - rempages -= cpa->numpages; - cpa->curpage += cpa->numpages; - } - -out: - /* Restore the original numpages */ - cpa->numpages = numpages; - return ret; -} - -static int change_page_attr_set_clr(unsigned long *addr, int numpages, - pgprot_t mask_set, pgprot_t mask_clr, - int force_split, int in_flag, - struct page **pages) -{ - struct cpa_data cpa; - int ret, cache, checkalias; - - memset(&cpa, 0, sizeof(cpa)); - - /* - * Check, if we are requested to set a not supported - * feature. Clearing non-supported features is OK. - */ - mask_set = canon_pgprot(mask_set); - - if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split) - return 0; - - /* Ensure we are PAGE_SIZE aligned */ - if (in_flag & CPA_ARRAY) { - int i; - for (i = 0; i < numpages; i++) { - if (addr[i] & ~PAGE_MASK) { - addr[i] &= PAGE_MASK; - WARN_ON_ONCE(1); - } - } - } else if (!(in_flag & CPA_PAGES_ARRAY)) { - /* - * in_flag of CPA_PAGES_ARRAY implies it is aligned. - * No need to check in that case - */ - if (*addr & ~PAGE_MASK) { - *addr &= PAGE_MASK; - /* - * People should not be passing in unaligned addresses: - */ - WARN_ON_ONCE(1); - } - } - - /* Must avoid aliasing mappings in the highmem code */ - kmap_flush_unused(); - - vm_unmap_aliases(); - - cpa.vaddr = addr; - cpa.pages = pages; - cpa.numpages = numpages; - cpa.mask_set = mask_set; - cpa.mask_clr = mask_clr; - cpa.flags = 0; - cpa.curpage = 0; - cpa.force_split = force_split; - - if (in_flag & (CPA_ARRAY | CPA_PAGES_ARRAY)) - cpa.flags |= in_flag; - - /* No alias checking for _NX bit modifications */ - checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX; - /* Has caller explicitly disabled alias checking? */ - if (in_flag & CPA_NO_CHECK_ALIAS) - checkalias = 0; - - ret = __change_page_attr_set_clr(&cpa, checkalias); - - /* - * Check whether we really changed something: - */ - if (!(cpa.flags & CPA_FLUSHTLB)) - goto out; - - /* - * No need to flush, when we did not set any of the caching - * attributes: - */ - cache = !!pgprot2cachemode(mask_set); - - /* - * On error; flush everything to be sure. - */ - if (ret) { - cpa_flush_all(cache); - goto out; - } - - cpa_flush(&cpa, cache); -out: - return ret; -} - -static inline int change_page_attr_set(unsigned long *addr, int numpages, - pgprot_t mask, int array) -{ - return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0, - (array ? CPA_ARRAY : 0), NULL); -} - -static inline int change_page_attr_clear(unsigned long *addr, int numpages, - pgprot_t mask, int array) -{ - return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0, - (array ? CPA_ARRAY : 0), NULL); -} - -static inline int cpa_set_pages_array(struct page **pages, int numpages, - pgprot_t mask) -{ - return change_page_attr_set_clr(NULL, numpages, mask, __pgprot(0), 0, - CPA_PAGES_ARRAY, pages); -} - -static inline int cpa_clear_pages_array(struct page **pages, int numpages, - pgprot_t mask) -{ - return change_page_attr_set_clr(NULL, numpages, __pgprot(0), mask, 0, - CPA_PAGES_ARRAY, pages); -} - -int _set_memory_uc(unsigned long addr, int numpages) -{ - /* - * for now UC MINUS. see comments in ioremap() - * If you really need strong UC use ioremap_uc(), but note - * that you cannot override IO areas with set_memory_*() as - * these helpers cannot work with IO memory. - */ - return change_page_attr_set(&addr, numpages, - cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS), - 0); -} - -int set_memory_uc(unsigned long addr, int numpages) -{ - int ret; - - /* - * for now UC MINUS. see comments in ioremap() - */ - ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, - _PAGE_CACHE_MODE_UC_MINUS, NULL); - if (ret) - goto out_err; - - ret = _set_memory_uc(addr, numpages); - if (ret) - goto out_free; - - return 0; - -out_free: - free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); -out_err: - return ret; -} -EXPORT_SYMBOL(set_memory_uc); - -int _set_memory_wc(unsigned long addr, int numpages) -{ - int ret; - - ret = change_page_attr_set(&addr, numpages, - cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS), - 0); - if (!ret) { - ret = change_page_attr_set_clr(&addr, numpages, - cachemode2pgprot(_PAGE_CACHE_MODE_WC), - __pgprot(_PAGE_CACHE_MASK), - 0, 0, NULL); - } - return ret; -} - -int set_memory_wc(unsigned long addr, int numpages) -{ - int ret; - - ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, - _PAGE_CACHE_MODE_WC, NULL); - if (ret) - return ret; - - ret = _set_memory_wc(addr, numpages); - if (ret) - free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); - - return ret; -} -EXPORT_SYMBOL(set_memory_wc); - -int _set_memory_wt(unsigned long addr, int numpages) -{ - return change_page_attr_set(&addr, numpages, - cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0); -} - -int _set_memory_wb(unsigned long addr, int numpages) -{ - /* WB cache mode is hard wired to all cache attribute bits being 0 */ - return change_page_attr_clear(&addr, numpages, - __pgprot(_PAGE_CACHE_MASK), 0); -} - -int set_memory_wb(unsigned long addr, int numpages) -{ - int ret; - - ret = _set_memory_wb(addr, numpages); - if (ret) - return ret; - - free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); - return 0; -} -EXPORT_SYMBOL(set_memory_wb); - -int set_memory_x(unsigned long addr, int numpages) -{ - if (!(__supported_pte_mask & _PAGE_NX)) - return 0; - - return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_NX), 0); -} - -int set_memory_nx(unsigned long addr, int numpages) -{ - if (!(__supported_pte_mask & _PAGE_NX)) - return 0; - - return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_NX), 0); -} - -int set_memory_ro(unsigned long addr, int numpages) -{ - return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0); -} - -int set_memory_rw(unsigned long addr, int numpages) -{ - return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_RW), 0); -} - -int set_memory_np(unsigned long addr, int numpages) -{ - return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_PRESENT), 0); -} - -int set_memory_np_noalias(unsigned long addr, int numpages) -{ - int cpa_flags = CPA_NO_CHECK_ALIAS; - - return change_page_attr_set_clr(&addr, numpages, __pgprot(0), - __pgprot(_PAGE_PRESENT), 0, - cpa_flags, NULL); -} - -int set_memory_4k(unsigned long addr, int numpages) -{ - return change_page_attr_set_clr(&addr, numpages, __pgprot(0), - __pgprot(0), 1, 0, NULL); -} - -int set_memory_nonglobal(unsigned long addr, int numpages) -{ - return change_page_attr_clear(&addr, numpages, - __pgprot(_PAGE_GLOBAL), 0); -} - -int set_memory_global(unsigned long addr, int numpages) -{ - return change_page_attr_set(&addr, numpages, - __pgprot(_PAGE_GLOBAL), 0); -} - -static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) -{ - struct cpa_data cpa; - int ret; - - /* Nothing to do if memory encryption is not active */ - if (!mem_encrypt_active()) - return 0; - - /* Should not be working on unaligned addresses */ - if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr)) - addr &= PAGE_MASK; - - memset(&cpa, 0, sizeof(cpa)); - cpa.vaddr = &addr; - cpa.numpages = numpages; - cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0); - cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC); - cpa.pgd = init_mm.pgd; - - /* Must avoid aliasing mappings in the highmem code */ - kmap_flush_unused(); - vm_unmap_aliases(); - - /* - * Before changing the encryption attribute, we need to flush caches. - */ - cpa_flush(&cpa, 1); - - ret = __change_page_attr_set_clr(&cpa, 1); - - /* - * After changing the encryption attribute, we need to flush TLBs again - * in case any speculative TLB caching occurred (but no need to flush - * caches again). We could just use cpa_flush_all(), but in case TLB - * flushing gets optimized in the cpa_flush() path use the same logic - * as above. - */ - cpa_flush(&cpa, 0); - - return ret; -} - -int set_memory_encrypted(unsigned long addr, int numpages) -{ - return __set_memory_enc_dec(addr, numpages, true); -} -EXPORT_SYMBOL_GPL(set_memory_encrypted); - -int set_memory_decrypted(unsigned long addr, int numpages) -{ - return __set_memory_enc_dec(addr, numpages, false); -} -EXPORT_SYMBOL_GPL(set_memory_decrypted); - -int set_pages_uc(struct page *page, int numpages) -{ - unsigned long addr = (unsigned long)page_address(page); - - return set_memory_uc(addr, numpages); -} -EXPORT_SYMBOL(set_pages_uc); - -static int _set_pages_array(struct page **pages, int numpages, - enum page_cache_mode new_type) -{ - unsigned long start; - unsigned long end; - enum page_cache_mode set_type; - int i; - int free_idx; - int ret; - - for (i = 0; i < numpages; i++) { - if (PageHighMem(pages[i])) - continue; - start = page_to_pfn(pages[i]) << PAGE_SHIFT; - end = start + PAGE_SIZE; - if (reserve_memtype(start, end, new_type, NULL)) - goto err_out; - } - - /* If WC, set to UC- first and then WC */ - set_type = (new_type == _PAGE_CACHE_MODE_WC) ? - _PAGE_CACHE_MODE_UC_MINUS : new_type; - - ret = cpa_set_pages_array(pages, numpages, - cachemode2pgprot(set_type)); - if (!ret && new_type == _PAGE_CACHE_MODE_WC) - ret = change_page_attr_set_clr(NULL, numpages, - cachemode2pgprot( - _PAGE_CACHE_MODE_WC), - __pgprot(_PAGE_CACHE_MASK), - 0, CPA_PAGES_ARRAY, pages); - if (ret) - goto err_out; - return 0; /* Success */ -err_out: - free_idx = i; - for (i = 0; i < free_idx; i++) { - if (PageHighMem(pages[i])) - continue; - start = page_to_pfn(pages[i]) << PAGE_SHIFT; - end = start + PAGE_SIZE; - free_memtype(start, end); - } - return -EINVAL; -} - -int set_pages_array_uc(struct page **pages, int numpages) -{ - return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_UC_MINUS); -} -EXPORT_SYMBOL(set_pages_array_uc); - -int set_pages_array_wc(struct page **pages, int numpages) -{ - return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WC); -} -EXPORT_SYMBOL(set_pages_array_wc); - -int set_pages_array_wt(struct page **pages, int numpages) -{ - return _set_pages_array(pages, numpages, _PAGE_CACHE_MODE_WT); -} -EXPORT_SYMBOL_GPL(set_pages_array_wt); - -int set_pages_wb(struct page *page, int numpages) -{ - unsigned long addr = (unsigned long)page_address(page); - - return set_memory_wb(addr, numpages); -} -EXPORT_SYMBOL(set_pages_wb); - -int set_pages_array_wb(struct page **pages, int numpages) -{ - int retval; - unsigned long start; - unsigned long end; - int i; - - /* WB cache mode is hard wired to all cache attribute bits being 0 */ - retval = cpa_clear_pages_array(pages, numpages, - __pgprot(_PAGE_CACHE_MASK)); - if (retval) - return retval; - - for (i = 0; i < numpages; i++) { - if (PageHighMem(pages[i])) - continue; - start = page_to_pfn(pages[i]) << PAGE_SHIFT; - end = start + PAGE_SIZE; - free_memtype(start, end); - } - - return 0; -} -EXPORT_SYMBOL(set_pages_array_wb); - -int set_pages_ro(struct page *page, int numpages) -{ - unsigned long addr = (unsigned long)page_address(page); - - return set_memory_ro(addr, numpages); -} - -int set_pages_rw(struct page *page, int numpages) -{ - unsigned long addr = (unsigned long)page_address(page); - - return set_memory_rw(addr, numpages); -} - -static int __set_pages_p(struct page *page, int numpages) -{ - unsigned long tempaddr = (unsigned long) page_address(page); - struct cpa_data cpa = { .vaddr = &tempaddr, - .pgd = NULL, - .numpages = numpages, - .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW), - .mask_clr = __pgprot(0), - .flags = 0}; - - /* - * No alias checking needed for setting present flag. otherwise, - * we may need to break large pages for 64-bit kernel text - * mappings (this adds to complexity if we want to do this from - * atomic context especially). Let's keep it simple! - */ - return __change_page_attr_set_clr(&cpa, 0); -} - -static int __set_pages_np(struct page *page, int numpages) -{ - unsigned long tempaddr = (unsigned long) page_address(page); - struct cpa_data cpa = { .vaddr = &tempaddr, - .pgd = NULL, - .numpages = numpages, - .mask_set = __pgprot(0), - .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), - .flags = 0}; - - /* - * No alias checking needed for setting not present flag. otherwise, - * we may need to break large pages for 64-bit kernel text - * mappings (this adds to complexity if we want to do this from - * atomic context especially). Let's keep it simple! - */ - return __change_page_attr_set_clr(&cpa, 0); -} - -int set_direct_map_invalid_noflush(struct page *page) -{ - return __set_pages_np(page, 1); -} - -int set_direct_map_default_noflush(struct page *page) -{ - return __set_pages_p(page, 1); -} - -void __kernel_map_pages(struct page *page, int numpages, int enable) -{ - if (PageHighMem(page)) - return; - if (!enable) { - debug_check_no_locks_freed(page_address(page), - numpages * PAGE_SIZE); - } - - /* - * The return value is ignored as the calls cannot fail. - * Large pages for identity mappings are not used at boot time - * and hence no memory allocations during large page split. - */ - if (enable) - __set_pages_p(page, numpages); - else - __set_pages_np(page, numpages); - - /* - * We should perform an IPI and flush all tlbs, - * but that can deadlock->flush only current cpu. - * Preemption needs to be disabled around __flush_tlb_all() due to - * CR3 reload in __native_flush_tlb(). - */ - preempt_disable(); - __flush_tlb_all(); - preempt_enable(); - - arch_flush_lazy_mmu_mode(); -} - -#ifdef CONFIG_HIBERNATION -bool kernel_page_present(struct page *page) -{ - unsigned int level; - pte_t *pte; - - if (PageHighMem(page)) - return false; - - pte = lookup_address((unsigned long)page_address(page), &level); - return (pte_val(*pte) & _PAGE_PRESENT); -} -#endif /* CONFIG_HIBERNATION */ - -int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address, - unsigned numpages, unsigned long page_flags) -{ - int retval = -EINVAL; - - struct cpa_data cpa = { - .vaddr = &address, - .pfn = pfn, - .pgd = pgd, - .numpages = numpages, - .mask_set = __pgprot(0), - .mask_clr = __pgprot(0), - .flags = 0, - }; - - WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP"); - - if (!(__supported_pte_mask & _PAGE_NX)) - goto out; - - if (!(page_flags & _PAGE_NX)) - cpa.mask_clr = __pgprot(_PAGE_NX); - - if (!(page_flags & _PAGE_RW)) - cpa.mask_clr = __pgprot(_PAGE_RW); - - if (!(page_flags & _PAGE_ENC)) - cpa.mask_clr = pgprot_encrypted(cpa.mask_clr); - - cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags); - - retval = __change_page_attr_set_clr(&cpa, 0); - __flush_tlb_all(); - -out: - return retval; -} - -/* - * __flush_tlb_all() flushes mappings only on current CPU and hence this - * function shouldn't be used in an SMP environment. Presently, it's used only - * during boot (way before smp_init()) by EFI subsystem and hence is ok. - */ -int __init kernel_unmap_pages_in_pgd(pgd_t *pgd, unsigned long address, - unsigned long numpages) -{ - int retval; - - /* - * The typical sequence for unmapping is to find a pte through - * lookup_address_in_pgd() (ideally, it should never return NULL because - * the address is already mapped) and change it's protections. As pfn is - * the *target* of a mapping, it's not useful while unmapping. - */ - struct cpa_data cpa = { - .vaddr = &address, - .pfn = 0, - .pgd = pgd, - .numpages = numpages, - .mask_set = __pgprot(0), - .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW), - .flags = 0, - }; - - WARN_ONCE(num_online_cpus() > 1, "Don't call after initializing SMP"); - - retval = __change_page_attr_set_clr(&cpa, 0); - __flush_tlb_all(); - - return retval; -} - -/* - * The testcases use internal knowledge of the implementation that shouldn't - * be exposed to the rest of the kernel. Include these directly here. - */ -#ifdef CONFIG_CPA_DEBUG -#include "pageattr-test.c" -#endif |