| /* |
| * Copyright 2002 Andi Kleen, SuSE Labs. |
| * Thanks to Ben LaHaise for precious feedback. |
| */ |
| #include <linux/highmem.h> |
| #include <linux/bootmem.h> |
| #include <linux/module.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/mm.h> |
| #include <linux/interrupt.h> |
| #include <linux/seq_file.h> |
| #include <linux/debugfs.h> |
| |
| #include <asm/e820.h> |
| #include <asm/processor.h> |
| #include <asm/tlbflush.h> |
| #include <asm/sections.h> |
| #include <asm/uaccess.h> |
| #include <asm/pgalloc.h> |
| #include <asm/proto.h> |
| #include <asm/pat.h> |
| |
| /* |
| * The current flushing context - we pass it instead of 5 arguments: |
| */ |
| struct cpa_data { |
| unsigned long vaddr; |
| pgprot_t mask_set; |
| pgprot_t mask_clr; |
| int numpages; |
| int flushtlb; |
| unsigned long pfn; |
| unsigned force_split : 1; |
| }; |
| |
| #ifdef CONFIG_PROC_FS |
| static unsigned long direct_pages_count[PG_LEVEL_NUM]; |
| |
| void update_page_count(int level, unsigned long pages) |
| { |
| unsigned long flags; |
| |
| /* Protect against CPA */ |
| spin_lock_irqsave(&pgd_lock, flags); |
| direct_pages_count[level] += pages; |
| spin_unlock_irqrestore(&pgd_lock, flags); |
| } |
| |
| static void split_page_count(int level) |
| { |
| direct_pages_count[level]--; |
| direct_pages_count[level - 1] += PTRS_PER_PTE; |
| } |
| |
| int arch_report_meminfo(char *page) |
| { |
| int n = sprintf(page, "DirectMap4k: %8lu kB\n", |
| direct_pages_count[PG_LEVEL_4K] << 2); |
| #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) |
| n += sprintf(page + n, "DirectMap2M: %8lu kB\n", |
| direct_pages_count[PG_LEVEL_2M] << 11); |
| #else |
| n += sprintf(page + n, "DirectMap4M: %8lu kB\n", |
| direct_pages_count[PG_LEVEL_2M] << 12); |
| #endif |
| #ifdef CONFIG_X86_64 |
| if (direct_gbpages) |
| n += sprintf(page + n, "DirectMap1G: %8lu kB\n", |
| direct_pages_count[PG_LEVEL_1G] << 20); |
| #endif |
| return n; |
| } |
| #else |
| static inline void split_page_count(int level) { } |
| #endif |
| |
| #ifdef CONFIG_X86_64 |
| |
| static inline unsigned long highmap_start_pfn(void) |
| { |
| return __pa(_text) >> PAGE_SHIFT; |
| } |
| |
| static inline unsigned long highmap_end_pfn(void) |
| { |
| return __pa(roundup((unsigned long)_end, PMD_SIZE)) >> PAGE_SHIFT; |
| } |
| |
| #endif |
| |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| # define debug_pagealloc 1 |
| #else |
| # define debug_pagealloc 0 |
| #endif |
| |
| static inline int |
| within(unsigned long addr, unsigned long start, unsigned long end) |
| { |
| return addr >= start && addr < end; |
| } |
| |
| /* |
| * Flushing functions |
| */ |
| |
| /** |
| * clflush_cache_range - flush a cache range with clflush |
| * @addr: virtual start address |
| * @size: number of bytes to flush |
| * |
| * clflush is an unordered instruction which needs fencing with mfence |
| * to avoid ordering issues. |
| */ |
| void clflush_cache_range(void *vaddr, unsigned int size) |
| { |
| void *vend = vaddr + size - 1; |
| |
| mb(); |
| |
| for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size) |
| clflush(vaddr); |
| /* |
| * Flush any possible final partial cacheline: |
| */ |
| clflush(vend); |
| |
| mb(); |
| } |
| |
| 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_model >= 4) |
| wbinvd(); |
| } |
| |
| static void cpa_flush_all(unsigned long cache) |
| { |
| BUG_ON(irqs_disabled()); |
| |
| on_each_cpu(__cpa_flush_all, (void *) cache, 1); |
| } |
| |
| static void __cpa_flush_range(void *arg) |
| { |
| /* |
| * We could optimize that further and do individual per page |
| * tlb invalidates for a low number of pages. Caveat: we must |
| * flush the high aliases on 64bit as well. |
| */ |
| __flush_tlb_all(); |
| } |
| |
| static void cpa_flush_range(unsigned long start, int numpages, int cache) |
| { |
| unsigned int i, level; |
| unsigned long addr; |
| |
| BUG_ON(irqs_disabled()); |
| WARN_ON(PAGE_ALIGN(start) != start); |
| |
| on_each_cpu(__cpa_flush_range, NULL, 1); |
| |
| if (!cache) |
| return; |
| |
| /* |
| * We only need to flush on one CPU, |
| * clflush is a MESI-coherent instruction that |
| * will cause all other CPUs to flush the same |
| * cachelines: |
| */ |
| for (i = 0, addr = start; i < numpages; i++, addr += PAGE_SIZE) { |
| pte_t *pte = lookup_address(addr, &level); |
| |
| /* |
| * Only flush present addresses: |
| */ |
| if (pte && (pte_val(*pte) & _PAGE_PRESENT)) |
| clflush_cache_range((void *) addr, PAGE_SIZE); |
| } |
| } |
| |
| /* |
| * 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 address, |
| unsigned long pfn) |
| { |
| pgprot_t forbidden = __pgprot(0); |
| |
| /* |
| * The BIOS area between 640k and 1Mb needs to be executable for |
| * PCI BIOS based config access (CONFIG_PCI_GOBIOS) support. |
| */ |
| if (within(pfn, BIOS_BEGIN >> PAGE_SHIFT, BIOS_END >> PAGE_SHIFT)) |
| pgprot_val(forbidden) |= _PAGE_NX; |
| |
| /* |
| * The kernel text needs to be executable for obvious reasons |
| * Does not cover __inittext since that is gone later on. On |
| * 64bit we do not enforce !NX on the low mapping |
| */ |
| if (within(address, (unsigned long)_text, (unsigned long)_etext)) |
| pgprot_val(forbidden) |= _PAGE_NX; |
| |
| /* |
| * The .rodata section needs to be read-only. Using the pfn |
| * catches all aliases. |
| */ |
| if (within(pfn, __pa((unsigned long)__start_rodata) >> PAGE_SHIFT, |
| __pa((unsigned long)__end_rodata) >> PAGE_SHIFT)) |
| pgprot_val(forbidden) |= _PAGE_RW; |
| |
| prot = __pgprot(pgprot_val(prot) & ~pgprot_val(forbidden)); |
| |
| return prot; |
| } |
| |
| /* |
| * 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) |
| { |
| pgd_t *pgd = pgd_offset_k(address); |
| pud_t *pud; |
| pmd_t *pmd; |
| |
| *level = PG_LEVEL_NONE; |
| |
| if (pgd_none(*pgd)) |
| return NULL; |
| |
| pud = pud_offset(pgd, 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); |
| } |
| EXPORT_SYMBOL_GPL(lookup_address); |
| |
| /* |
| * 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; |
| pud_t *pud; |
| pmd_t *pmd; |
| |
| pgd = (pgd_t *)page_address(page) + pgd_index(address); |
| pud = pud_offset(pgd, address); |
| pmd = pmd_offset(pud, address); |
| set_pte_atomic((pte_t *)pmd, pte); |
| } |
| } |
| #endif |
| } |
| |
| static int |
| try_preserve_large_page(pte_t *kpte, unsigned long address, |
| struct cpa_data *cpa) |
| { |
| unsigned long nextpage_addr, numpages, pmask, psize, flags, addr, pfn; |
| pte_t new_pte, old_pte, *tmp; |
| pgprot_t old_prot, new_prot; |
| int i, do_split = 1; |
| unsigned int level; |
| |
| if (cpa->force_split) |
| return 1; |
| |
| spin_lock_irqsave(&pgd_lock, flags); |
| /* |
| * Check for races, another CPU might have split this page |
| * up already: |
| */ |
| tmp = lookup_address(address, &level); |
| if (tmp != kpte) |
| goto out_unlock; |
| |
| switch (level) { |
| case PG_LEVEL_2M: |
| psize = PMD_PAGE_SIZE; |
| pmask = PMD_PAGE_MASK; |
| break; |
| #ifdef CONFIG_X86_64 |
| case PG_LEVEL_1G: |
| psize = PUD_PAGE_SIZE; |
| pmask = PUD_PAGE_MASK; |
| break; |
| #endif |
| default: |
| do_split = -EINVAL; |
| goto out_unlock; |
| } |
| |
| /* |
| * Calculate the number of pages, which fit into this large |
| * page starting at address: |
| */ |
| nextpage_addr = (address + psize) & pmask; |
| numpages = (nextpage_addr - address) >> PAGE_SHIFT; |
| if (numpages < cpa->numpages) |
| cpa->numpages = numpages; |
| |
| /* |
| * We are safe now. Check whether the new pgprot is the same: |
| */ |
| old_pte = *kpte; |
| old_prot = new_prot = pte_pgprot(old_pte); |
| |
| pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr); |
| pgprot_val(new_prot) |= pgprot_val(cpa->mask_set); |
| |
| /* |
| * old_pte points to the large page base address. So we need |
| * to add the offset of the virtual address: |
| */ |
| pfn = pte_pfn(old_pte) + ((address & (psize - 1)) >> PAGE_SHIFT); |
| cpa->pfn = pfn; |
| |
| new_prot = static_protections(new_prot, address, pfn); |
| |
| /* |
| * We need to check the full range, whether |
| * static_protection() requires a different pgprot for one of |
| * the pages in the range we try to preserve: |
| */ |
| addr = address + PAGE_SIZE; |
| pfn++; |
| for (i = 1; i < cpa->numpages; i++, addr += PAGE_SIZE, pfn++) { |
| pgprot_t chk_prot = static_protections(new_prot, addr, pfn); |
| |
| if (pgprot_val(chk_prot) != pgprot_val(new_prot)) |
| goto out_unlock; |
| } |
| |
| /* |
| * If there are no changes, return. maxpages has been updated |
| * above: |
| */ |
| if (pgprot_val(new_prot) == pgprot_val(old_prot)) { |
| do_split = 0; |
| goto out_unlock; |
| } |
| |
| /* |
| * We need to change the attributes. Check, whether we can |
| * change the large page in one go. We request a split, when |
| * the address is not aligned and the number of pages is |
| * smaller than the number of pages in the large page. Note |
| * that we limited the number of possible pages already to |
| * the number of pages in the large page. |
| */ |
| if (address == (nextpage_addr - psize) && cpa->numpages == numpages) { |
| /* |
| * The address is aligned and the number of pages |
| * covers the full page. |
| */ |
| new_pte = pfn_pte(pte_pfn(old_pte), canon_pgprot(new_prot)); |
| __set_pmd_pte(kpte, address, new_pte); |
| cpa->flushtlb = 1; |
| do_split = 0; |
| } |
| |
| out_unlock: |
| spin_unlock_irqrestore(&pgd_lock, flags); |
| |
| return do_split; |
| } |
| |
| static LIST_HEAD(page_pool); |
| static unsigned long pool_size, pool_pages, pool_low; |
| static unsigned long pool_used, pool_failed; |
| |
| static void cpa_fill_pool(struct page **ret) |
| { |
| gfp_t gfp = GFP_KERNEL; |
| unsigned long flags; |
| struct page *p; |
| |
| /* |
| * Avoid recursion (on debug-pagealloc) and also signal |
| * our priority to get to these pagetables: |
| */ |
| if (current->flags & PF_MEMALLOC) |
| return; |
| current->flags |= PF_MEMALLOC; |
| |
| /* |
| * Allocate atomically from atomic contexts: |
| */ |
| if (in_atomic() || irqs_disabled() || debug_pagealloc) |
| gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; |
| |
| while (pool_pages < pool_size || (ret && !*ret)) { |
| p = alloc_pages(gfp, 0); |
| if (!p) { |
| pool_failed++; |
| break; |
| } |
| /* |
| * If the call site needs a page right now, provide it: |
| */ |
| if (ret && !*ret) { |
| *ret = p; |
| continue; |
| } |
| spin_lock_irqsave(&pgd_lock, flags); |
| list_add(&p->lru, &page_pool); |
| pool_pages++; |
| spin_unlock_irqrestore(&pgd_lock, flags); |
| } |
| |
| current->flags &= ~PF_MEMALLOC; |
| } |
| |
| #define SHIFT_MB (20 - PAGE_SHIFT) |
| #define ROUND_MB_GB ((1 << 10) - 1) |
| #define SHIFT_MB_GB 10 |
| #define POOL_PAGES_PER_GB 16 |
| |
| void __init cpa_init(void) |
| { |
| struct sysinfo si; |
| unsigned long gb; |
| |
| si_meminfo(&si); |
| /* |
| * Calculate the number of pool pages: |
| * |
| * Convert totalram (nr of pages) to MiB and round to the next |
| * GiB. Shift MiB to Gib and multiply the result by |
| * POOL_PAGES_PER_GB: |
| */ |
| if (debug_pagealloc) { |
| gb = ((si.totalram >> SHIFT_MB) + ROUND_MB_GB) >> SHIFT_MB_GB; |
| pool_size = POOL_PAGES_PER_GB * gb; |
| } else { |
| pool_size = 1; |
| } |
| pool_low = pool_size; |
| |
| cpa_fill_pool(NULL); |
| printk(KERN_DEBUG |
| "CPA: page pool initialized %lu of %lu pages preallocated\n", |
| pool_pages, pool_size); |
| } |
| |
| static int split_large_page(pte_t *kpte, unsigned long address) |
| { |
| unsigned long flags, pfn, pfninc = 1; |
| unsigned int i, level; |
| pte_t *pbase, *tmp; |
| pgprot_t ref_prot; |
| struct page *base; |
| |
| /* |
| * Get a page from the pool. The pool list is protected by the |
| * pgd_lock, which we have to take anyway for the split |
| * operation: |
| */ |
| spin_lock_irqsave(&pgd_lock, flags); |
| if (list_empty(&page_pool)) { |
| spin_unlock_irqrestore(&pgd_lock, flags); |
| base = NULL; |
| cpa_fill_pool(&base); |
| if (!base) |
| return -ENOMEM; |
| spin_lock_irqsave(&pgd_lock, flags); |
| } else { |
| base = list_first_entry(&page_pool, struct page, lru); |
| list_del(&base->lru); |
| pool_pages--; |
| |
| if (pool_pages < pool_low) |
| pool_low = pool_pages; |
| } |
| |
| /* |
| * Check for races, another CPU might have split this page |
| * up for us already: |
| */ |
| tmp = lookup_address(address, &level); |
| if (tmp != kpte) |
| goto out_unlock; |
| |
| pbase = (pte_t *)page_address(base); |
| paravirt_alloc_pte(&init_mm, page_to_pfn(base)); |
| ref_prot = pte_pgprot(pte_clrhuge(*kpte)); |
| |
| #ifdef CONFIG_X86_64 |
| if (level == PG_LEVEL_1G) { |
| pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT; |
| pgprot_val(ref_prot) |= _PAGE_PSE; |
| } |
| #endif |
| |
| /* |
| * Get the target pfn from the original entry: |
| */ |
| pfn = pte_pfn(*kpte); |
| for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc) |
| set_pte(&pbase[i], pfn_pte(pfn, ref_prot)); |
| |
| if (address >= (unsigned long)__va(0) && |
| address < (unsigned long)__va(max_low_pfn_mapped << PAGE_SHIFT)) |
| split_page_count(level); |
| |
| #ifdef CONFIG_X86_64 |
| if (address >= (unsigned long)__va(1UL<<32) && |
| address < (unsigned long)__va(max_pfn_mapped << PAGE_SHIFT)) |
| split_page_count(level); |
| #endif |
| |
| /* |
| * Install the new, split up pagetable. Important details here: |
| * |
| * On Intel the NX bit of all levels must be cleared to make a |
| * page executable. See section 4.13.2 of Intel 64 and IA-32 |
| * Architectures Software Developer's Manual). |
| * |
| * Mark the entry present. The current mapping might be |
| * set to not present, which we preserved above. |
| */ |
| ref_prot = pte_pgprot(pte_mkexec(pte_clrhuge(*kpte))); |
| pgprot_val(ref_prot) |= _PAGE_PRESENT; |
| __set_pmd_pte(kpte, address, mk_pte(base, ref_prot)); |
| base = NULL; |
| |
| out_unlock: |
| /* |
| * If we dropped out via the lookup_address check under |
| * pgd_lock then stick the page back into the pool: |
| */ |
| if (base) { |
| list_add(&base->lru, &page_pool); |
| pool_pages++; |
| } else |
| pool_used++; |
| spin_unlock_irqrestore(&pgd_lock, flags); |
| |
| return 0; |
| } |
| |
| static int __change_page_attr(struct cpa_data *cpa, int primary) |
| { |
| unsigned long address = cpa->vaddr; |
| int do_split, err; |
| unsigned int level; |
| pte_t *kpte, old_pte; |
| |
| repeat: |
| kpte = lookup_address(address, &level); |
| if (!kpte) |
| return 0; |
| |
| old_pte = *kpte; |
| if (!pte_val(old_pte)) { |
| if (!primary) |
| return 0; |
| WARN(1, KERN_WARNING "CPA: called for zero pte. " |
| "vaddr = %lx cpa->vaddr = %lx\n", address, |
| cpa->vaddr); |
| return -EINVAL; |
| } |
| |
| 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); |
| |
| new_prot = static_protections(new_prot, address, pfn); |
| |
| /* |
| * 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, canon_pgprot(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->flushtlb = 1; |
| } |
| cpa->numpages = 1; |
| return 0; |
| } |
| |
| /* |
| * Check, whether we can keep the large page intact |
| * and just change the pte: |
| */ |
| do_split = try_preserve_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(kpte, address); |
| if (!err) { |
| cpa->flushtlb = 1; |
| 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; |
| int ret = 0; |
| |
| if (cpa->pfn >= max_pfn_mapped) |
| return 0; |
| |
| #ifdef CONFIG_X86_64 |
| if (cpa->pfn >= max_low_pfn_mapped && cpa->pfn < (1UL<<(32-PAGE_SHIFT))) |
| return 0; |
| #endif |
| /* |
| * No need to redo, when the primary call touched the direct |
| * mapping already: |
| */ |
| if (!(within(cpa->vaddr, PAGE_OFFSET, |
| PAGE_OFFSET + (max_low_pfn_mapped << PAGE_SHIFT)) |
| #ifdef CONFIG_X86_64 |
| || within(cpa->vaddr, PAGE_OFFSET + (1UL<<32), |
| PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT)) |
| #endif |
| )) { |
| |
| alias_cpa = *cpa; |
| alias_cpa.vaddr = (unsigned long) __va(cpa->pfn << PAGE_SHIFT); |
| |
| ret = __change_page_attr_set_clr(&alias_cpa, 0); |
| } |
| |
| #ifdef CONFIG_X86_64 |
| if (ret) |
| return ret; |
| /* |
| * No need to redo, when the primary call touched the high |
| * mapping already: |
| */ |
| if (within(cpa->vaddr, (unsigned long) _text, (unsigned long) _end)) |
| return 0; |
| |
| /* |
| * If the physical address is inside the kernel map, we need |
| * to touch the high mapped kernel as well: |
| */ |
| if (!within(cpa->pfn, highmap_start_pfn(), highmap_end_pfn())) |
| return 0; |
| |
| alias_cpa = *cpa; |
| alias_cpa.vaddr = |
| (cpa->pfn << PAGE_SHIFT) + __START_KERNEL_map - phys_base; |
| |
| /* |
| * The high mapping range is imprecise, so ignore the return value. |
| */ |
| __change_page_attr_set_clr(&alias_cpa, 0); |
| #endif |
| return ret; |
| } |
| |
| static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias) |
| { |
| int ret, numpages = cpa->numpages; |
| |
| while (numpages) { |
| /* |
| * Store the remaining nr of pages for the large page |
| * preservation check. |
| */ |
| cpa->numpages = numpages; |
| |
| ret = __change_page_attr(cpa, checkalias); |
| if (ret) |
| return ret; |
| |
| if (checkalias) { |
| ret = cpa_process_alias(cpa); |
| if (ret) |
| return ret; |
| } |
| |
| /* |
| * 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 > numpages); |
| numpages -= cpa->numpages; |
| cpa->vaddr += cpa->numpages * PAGE_SIZE; |
| } |
| return 0; |
| } |
| |
| static inline int cache_attr(pgprot_t attr) |
| { |
| return pgprot_val(attr) & |
| (_PAGE_PAT | _PAGE_PAT_LARGE | _PAGE_PWT | _PAGE_PCD); |
| } |
| |
| static int change_page_attr_set_clr(unsigned long addr, int numpages, |
| pgprot_t mask_set, pgprot_t mask_clr, |
| int force_split) |
| { |
| struct cpa_data cpa; |
| int ret, cache, checkalias; |
| |
| /* |
| * Check, if we are requested to change a not supported |
| * feature: |
| */ |
| mask_set = canon_pgprot(mask_set); |
| mask_clr = canon_pgprot(mask_clr); |
| if (!pgprot_val(mask_set) && !pgprot_val(mask_clr) && !force_split) |
| return 0; |
| |
| /* Ensure we are PAGE_SIZE aligned */ |
| if (addr & ~PAGE_MASK) { |
| addr &= PAGE_MASK; |
| /* |
| * People should not be passing in unaligned addresses: |
| */ |
| WARN_ON_ONCE(1); |
| } |
| |
| cpa.vaddr = addr; |
| cpa.numpages = numpages; |
| cpa.mask_set = mask_set; |
| cpa.mask_clr = mask_clr; |
| cpa.flushtlb = 0; |
| cpa.force_split = force_split; |
| |
| /* No alias checking for _NX bit modifications */ |
| checkalias = (pgprot_val(mask_set) | pgprot_val(mask_clr)) != _PAGE_NX; |
| |
| ret = __change_page_attr_set_clr(&cpa, checkalias); |
| |
| /* |
| * Check whether we really changed something: |
| */ |
| if (!cpa.flushtlb) |
| goto out; |
| |
| /* |
| * No need to flush, when we did not set any of the caching |
| * attributes: |
| */ |
| cache = cache_attr(mask_set); |
| |
| /* |
| * On success we use clflush, when the CPU supports it to |
| * avoid the wbindv. If the CPU does not support it and in the |
| * error case we fall back to cpa_flush_all (which uses |
| * wbindv): |
| */ |
| if (!ret && cpu_has_clflush) |
| cpa_flush_range(addr, numpages, cache); |
| else |
| cpa_flush_all(cache); |
| |
| out: |
| cpa_fill_pool(NULL); |
| |
| return ret; |
| } |
| |
| static inline int change_page_attr_set(unsigned long addr, int numpages, |
| pgprot_t mask) |
| { |
| return change_page_attr_set_clr(addr, numpages, mask, __pgprot(0), 0); |
| } |
| |
| static inline int change_page_attr_clear(unsigned long addr, int numpages, |
| pgprot_t mask) |
| { |
| return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask, 0); |
| } |
| |
| int _set_memory_uc(unsigned long addr, int numpages) |
| { |
| /* |
| * for now UC MINUS. see comments in ioremap_nocache() |
| */ |
| return change_page_attr_set(addr, numpages, |
| __pgprot(_PAGE_CACHE_UC_MINUS)); |
| } |
| |
| int set_memory_uc(unsigned long addr, int numpages) |
| { |
| /* |
| * for now UC MINUS. see comments in ioremap_nocache() |
| */ |
| if (reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, |
| _PAGE_CACHE_UC_MINUS, NULL)) |
| return -EINVAL; |
| |
| return _set_memory_uc(addr, numpages); |
| } |
| EXPORT_SYMBOL(set_memory_uc); |
| |
| int _set_memory_wc(unsigned long addr, int numpages) |
| { |
| return change_page_attr_set(addr, numpages, |
| __pgprot(_PAGE_CACHE_WC)); |
| } |
| |
| int set_memory_wc(unsigned long addr, int numpages) |
| { |
| if (!pat_enabled) |
| return set_memory_uc(addr, numpages); |
| |
| if (reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, |
| _PAGE_CACHE_WC, NULL)) |
| return -EINVAL; |
| |
| return _set_memory_wc(addr, numpages); |
| } |
| EXPORT_SYMBOL(set_memory_wc); |
| |
| int _set_memory_wb(unsigned long addr, int numpages) |
| { |
| return change_page_attr_clear(addr, numpages, |
| __pgprot(_PAGE_CACHE_MASK)); |
| } |
| |
| int set_memory_wb(unsigned long addr, int numpages) |
| { |
| free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); |
| |
| return _set_memory_wb(addr, numpages); |
| } |
| EXPORT_SYMBOL(set_memory_wb); |
| |
| int set_memory_x(unsigned long addr, int numpages) |
| { |
| return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_NX)); |
| } |
| EXPORT_SYMBOL(set_memory_x); |
| |
| int set_memory_nx(unsigned long addr, int numpages) |
| { |
| return change_page_attr_set(addr, numpages, __pgprot(_PAGE_NX)); |
| } |
| EXPORT_SYMBOL(set_memory_nx); |
| |
| int set_memory_ro(unsigned long addr, int numpages) |
| { |
| return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_RW)); |
| } |
| EXPORT_SYMBOL_GPL(set_memory_ro); |
| |
| int set_memory_rw(unsigned long addr, int numpages) |
| { |
| return change_page_attr_set(addr, numpages, __pgprot(_PAGE_RW)); |
| } |
| EXPORT_SYMBOL_GPL(set_memory_rw); |
| |
| int set_memory_np(unsigned long addr, int numpages) |
| { |
| return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_PRESENT)); |
| } |
| |
| int set_memory_4k(unsigned long addr, int numpages) |
| { |
| return change_page_attr_set_clr(addr, numpages, __pgprot(0), |
| __pgprot(0), 1); |
| } |
| |
| 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); |
| |
| 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_x(struct page *page, int numpages) |
| { |
| unsigned long addr = (unsigned long)page_address(page); |
| |
| return set_memory_x(addr, numpages); |
| } |
| EXPORT_SYMBOL(set_pages_x); |
| |
| int set_pages_nx(struct page *page, int numpages) |
| { |
| unsigned long addr = (unsigned long)page_address(page); |
| |
| return set_memory_nx(addr, numpages); |
| } |
| EXPORT_SYMBOL(set_pages_nx); |
| |
| 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); |
| } |
| |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| |
| static int __set_pages_p(struct page *page, int numpages) |
| { |
| struct cpa_data cpa = { .vaddr = (unsigned long) page_address(page), |
| .numpages = numpages, |
| .mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW), |
| .mask_clr = __pgprot(0)}; |
| |
| return __change_page_attr_set_clr(&cpa, 1); |
| } |
| |
| static int __set_pages_np(struct page *page, int numpages) |
| { |
| struct cpa_data cpa = { .vaddr = (unsigned long) page_address(page), |
| .numpages = numpages, |
| .mask_set = __pgprot(0), |
| .mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW)}; |
| |
| return __change_page_attr_set_clr(&cpa, 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); |
| } |
| |
| /* |
| * If page allocator is not up yet then do not call c_p_a(): |
| */ |
| if (!debug_pagealloc_enabled) |
| return; |
| |
| /* |
| * The return value is ignored as the calls cannot fail. |
| * Large pages are kept enabled at boot time, and are |
| * split up quickly with DEBUG_PAGEALLOC. If a splitup |
| * fails here (due to temporary memory shortage) no damage |
| * is done because we just keep the largepage intact up |
| * to the next attempt when it will likely be split up: |
| */ |
| 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: |
| */ |
| __flush_tlb_all(); |
| |
| /* |
| * Try to refill the page pool here. We can do this only after |
| * the tlb flush. |
| */ |
| cpa_fill_pool(NULL); |
| } |
| |
| #ifdef CONFIG_DEBUG_FS |
| static int dpa_show(struct seq_file *m, void *v) |
| { |
| seq_puts(m, "DEBUG_PAGEALLOC\n"); |
| seq_printf(m, "pool_size : %lu\n", pool_size); |
| seq_printf(m, "pool_pages : %lu\n", pool_pages); |
| seq_printf(m, "pool_low : %lu\n", pool_low); |
| seq_printf(m, "pool_used : %lu\n", pool_used); |
| seq_printf(m, "pool_failed : %lu\n", pool_failed); |
| |
| return 0; |
| } |
| |
| static int dpa_open(struct inode *inode, struct file *filp) |
| { |
| return single_open(filp, dpa_show, NULL); |
| } |
| |
| static const struct file_operations dpa_fops = { |
| .open = dpa_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static int __init debug_pagealloc_proc_init(void) |
| { |
| struct dentry *de; |
| |
| de = debugfs_create_file("debug_pagealloc", 0600, NULL, NULL, |
| &dpa_fops); |
| if (!de) |
| return -ENOMEM; |
| |
| return 0; |
| } |
| __initcall(debug_pagealloc_proc_init); |
| #endif |
| |
| #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 */ |
| |
| #endif /* CONFIG_DEBUG_PAGEALLOC */ |
| |
| /* |
| * 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 |