946 lines
22 KiB
C
946 lines
22 KiB
C
/*
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* Copyright 2002 Andi Kleen, SuSE Labs.
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* Thanks to Ben LaHaise for precious feedback.
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*/
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#include <linux/highmem.h>
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#include <linux/bootmem.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <linux/interrupt.h>
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#include <asm/e820.h>
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#include <asm/processor.h>
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#include <asm/tlbflush.h>
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#include <asm/sections.h>
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#include <asm/uaccess.h>
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#include <asm/pgalloc.h>
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#include <asm/proto.h>
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/*
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* The current flushing context - we pass it instead of 5 arguments:
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*/
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struct cpa_data {
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unsigned long vaddr;
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pgprot_t mask_set;
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pgprot_t mask_clr;
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int numpages;
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int flushtlb;
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unsigned long pfn;
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};
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#ifdef CONFIG_X86_64
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static inline unsigned long highmap_start_pfn(void)
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{
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return __pa(_text) >> PAGE_SHIFT;
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}
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static inline unsigned long highmap_end_pfn(void)
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{
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return __pa(round_up((unsigned long)_end, PMD_SIZE)) >> PAGE_SHIFT;
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}
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#endif
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#ifdef CONFIG_DEBUG_PAGEALLOC
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# define debug_pagealloc 1
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#else
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# define debug_pagealloc 0
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#endif
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static inline int
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within(unsigned long addr, unsigned long start, unsigned long end)
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{
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return addr >= start && addr < end;
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}
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/*
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* Flushing functions
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*/
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/**
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* clflush_cache_range - flush a cache range with clflush
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* @addr: virtual start address
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* @size: number of bytes to flush
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*
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* clflush is an unordered instruction which needs fencing with mfence
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* to avoid ordering issues.
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*/
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void clflush_cache_range(void *vaddr, unsigned int size)
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{
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void *vend = vaddr + size - 1;
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mb();
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for (; vaddr < vend; vaddr += boot_cpu_data.x86_clflush_size)
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clflush(vaddr);
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/*
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* Flush any possible final partial cacheline:
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*/
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clflush(vend);
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mb();
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}
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static void __cpa_flush_all(void *arg)
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{
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unsigned long cache = (unsigned long)arg;
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/*
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* Flush all to work around Errata in early athlons regarding
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* large page flushing.
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*/
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__flush_tlb_all();
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if (cache && boot_cpu_data.x86_model >= 4)
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wbinvd();
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}
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static void cpa_flush_all(unsigned long cache)
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{
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BUG_ON(irqs_disabled());
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on_each_cpu(__cpa_flush_all, (void *) cache, 1, 1);
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}
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static void __cpa_flush_range(void *arg)
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{
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/*
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* We could optimize that further and do individual per page
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* tlb invalidates for a low number of pages. Caveat: we must
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* flush the high aliases on 64bit as well.
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*/
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__flush_tlb_all();
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}
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static void cpa_flush_range(unsigned long start, int numpages, int cache)
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{
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unsigned int i, level;
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unsigned long addr;
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BUG_ON(irqs_disabled());
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WARN_ON(PAGE_ALIGN(start) != start);
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on_each_cpu(__cpa_flush_range, NULL, 1, 1);
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if (!cache)
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return;
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/*
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* We only need to flush on one CPU,
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* clflush is a MESI-coherent instruction that
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* will cause all other CPUs to flush the same
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* cachelines:
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*/
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for (i = 0, addr = start; i < numpages; i++, addr += PAGE_SIZE) {
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pte_t *pte = lookup_address(addr, &level);
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/*
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* Only flush present addresses:
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*/
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if (pte && (pte_val(*pte) & _PAGE_PRESENT))
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clflush_cache_range((void *) addr, PAGE_SIZE);
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}
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}
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/*
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* Certain areas of memory on x86 require very specific protection flags,
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* for example the BIOS area or kernel text. Callers don't always get this
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* right (again, ioremap() on BIOS memory is not uncommon) so this function
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* checks and fixes these known static required protection bits.
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*/
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static inline pgprot_t static_protections(pgprot_t prot, unsigned long address,
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unsigned long pfn)
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{
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pgprot_t forbidden = __pgprot(0);
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/*
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* The BIOS area between 640k and 1Mb needs to be executable for
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* PCI BIOS based config access (CONFIG_PCI_GOBIOS) support.
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*/
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if (within(pfn, BIOS_BEGIN >> PAGE_SHIFT, BIOS_END >> PAGE_SHIFT))
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pgprot_val(forbidden) |= _PAGE_NX;
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/*
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* The kernel text needs to be executable for obvious reasons
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* Does not cover __inittext since that is gone later on. On
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* 64bit we do not enforce !NX on the low mapping
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*/
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if (within(address, (unsigned long)_text, (unsigned long)_etext))
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pgprot_val(forbidden) |= _PAGE_NX;
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/*
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* The .rodata section needs to be read-only. Using the pfn
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* catches all aliases.
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*/
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if (within(pfn, __pa((unsigned long)__start_rodata) >> PAGE_SHIFT,
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__pa((unsigned long)__end_rodata) >> PAGE_SHIFT))
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pgprot_val(forbidden) |= _PAGE_RW;
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prot = __pgprot(pgprot_val(prot) & ~pgprot_val(forbidden));
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return prot;
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}
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/*
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* Lookup the page table entry for a virtual address. Return a pointer
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* to the entry and the level of the mapping.
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*
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* Note: We return pud and pmd either when the entry is marked large
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* or when the present bit is not set. Otherwise we would return a
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* pointer to a nonexisting mapping.
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*/
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pte_t *lookup_address(unsigned long address, unsigned int *level)
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{
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pgd_t *pgd = pgd_offset_k(address);
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pud_t *pud;
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pmd_t *pmd;
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*level = PG_LEVEL_NONE;
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if (pgd_none(*pgd))
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return NULL;
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pud = pud_offset(pgd, address);
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if (pud_none(*pud))
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return NULL;
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*level = PG_LEVEL_1G;
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if (pud_large(*pud) || !pud_present(*pud))
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return (pte_t *)pud;
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pmd = pmd_offset(pud, address);
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if (pmd_none(*pmd))
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return NULL;
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*level = PG_LEVEL_2M;
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if (pmd_large(*pmd) || !pmd_present(*pmd))
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return (pte_t *)pmd;
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*level = PG_LEVEL_4K;
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return pte_offset_kernel(pmd, address);
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}
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/*
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* Set the new pmd in all the pgds we know about:
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*/
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static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
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{
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/* change init_mm */
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set_pte_atomic(kpte, pte);
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#ifdef CONFIG_X86_32
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if (!SHARED_KERNEL_PMD) {
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struct page *page;
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list_for_each_entry(page, &pgd_list, lru) {
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pgd_t *pgd;
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pud_t *pud;
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pmd_t *pmd;
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pgd = (pgd_t *)page_address(page) + pgd_index(address);
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pud = pud_offset(pgd, address);
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pmd = pmd_offset(pud, address);
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set_pte_atomic((pte_t *)pmd, pte);
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}
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}
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#endif
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}
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static int
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try_preserve_large_page(pte_t *kpte, unsigned long address,
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struct cpa_data *cpa)
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{
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unsigned long nextpage_addr, numpages, pmask, psize, flags, addr, pfn;
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pte_t new_pte, old_pte, *tmp;
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pgprot_t old_prot, new_prot;
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int i, do_split = 1;
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unsigned int level;
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spin_lock_irqsave(&pgd_lock, flags);
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/*
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* Check for races, another CPU might have split this page
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* up already:
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*/
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tmp = lookup_address(address, &level);
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if (tmp != kpte)
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goto out_unlock;
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switch (level) {
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case PG_LEVEL_2M:
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psize = PMD_PAGE_SIZE;
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pmask = PMD_PAGE_MASK;
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break;
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#ifdef CONFIG_X86_64
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case PG_LEVEL_1G:
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psize = PUD_PAGE_SIZE;
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pmask = PUD_PAGE_MASK;
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break;
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#endif
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default:
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do_split = -EINVAL;
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goto out_unlock;
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}
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/*
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* Calculate the number of pages, which fit into this large
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* page starting at address:
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*/
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nextpage_addr = (address + psize) & pmask;
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numpages = (nextpage_addr - address) >> PAGE_SHIFT;
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if (numpages < cpa->numpages)
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cpa->numpages = numpages;
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/*
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* We are safe now. Check whether the new pgprot is the same:
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*/
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old_pte = *kpte;
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old_prot = new_prot = pte_pgprot(old_pte);
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pgprot_val(new_prot) &= ~pgprot_val(cpa->mask_clr);
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pgprot_val(new_prot) |= pgprot_val(cpa->mask_set);
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/*
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* old_pte points to the large page base address. So we need
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* to add the offset of the virtual address:
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*/
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pfn = pte_pfn(old_pte) + ((address & (psize - 1)) >> PAGE_SHIFT);
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cpa->pfn = pfn;
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new_prot = static_protections(new_prot, address, pfn);
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/*
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* We need to check the full range, whether
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* static_protection() requires a different pgprot for one of
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* the pages in the range we try to preserve:
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*/
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addr = address + PAGE_SIZE;
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pfn++;
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for (i = 1; i < cpa->numpages; i++, addr += PAGE_SIZE, pfn++) {
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pgprot_t chk_prot = static_protections(new_prot, addr, pfn);
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if (pgprot_val(chk_prot) != pgprot_val(new_prot))
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goto out_unlock;
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}
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/*
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* If there are no changes, return. maxpages has been updated
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* above:
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*/
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if (pgprot_val(new_prot) == pgprot_val(old_prot)) {
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do_split = 0;
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goto out_unlock;
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}
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/*
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* We need to change the attributes. Check, whether we can
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* change the large page in one go. We request a split, when
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* the address is not aligned and the number of pages is
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* smaller than the number of pages in the large page. Note
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* that we limited the number of possible pages already to
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* the number of pages in the large page.
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*/
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if (address == (nextpage_addr - psize) && cpa->numpages == numpages) {
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/*
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* The address is aligned and the number of pages
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* covers the full page.
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*/
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new_pte = pfn_pte(pte_pfn(old_pte), canon_pgprot(new_prot));
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__set_pmd_pte(kpte, address, new_pte);
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cpa->flushtlb = 1;
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do_split = 0;
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}
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out_unlock:
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spin_unlock_irqrestore(&pgd_lock, flags);
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return do_split;
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}
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static LIST_HEAD(page_pool);
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static unsigned long pool_size, pool_pages, pool_low;
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static unsigned long pool_used, pool_failed;
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static void cpa_fill_pool(struct page **ret)
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{
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gfp_t gfp = GFP_KERNEL;
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unsigned long flags;
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struct page *p;
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/*
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* Avoid recursion (on debug-pagealloc) and also signal
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* our priority to get to these pagetables:
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*/
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if (current->flags & PF_MEMALLOC)
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return;
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current->flags |= PF_MEMALLOC;
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/*
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* Allocate atomically from atomic contexts:
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*/
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if (in_atomic() || irqs_disabled() || debug_pagealloc)
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gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
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while (pool_pages < pool_size || (ret && !*ret)) {
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p = alloc_pages(gfp, 0);
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if (!p) {
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pool_failed++;
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break;
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}
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/*
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* If the call site needs a page right now, provide it:
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*/
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if (ret && !*ret) {
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*ret = p;
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continue;
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}
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spin_lock_irqsave(&pgd_lock, flags);
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list_add(&p->lru, &page_pool);
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pool_pages++;
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spin_unlock_irqrestore(&pgd_lock, flags);
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}
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current->flags &= ~PF_MEMALLOC;
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}
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#define SHIFT_MB (20 - PAGE_SHIFT)
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#define ROUND_MB_GB ((1 << 10) - 1)
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#define SHIFT_MB_GB 10
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#define POOL_PAGES_PER_GB 16
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void __init cpa_init(void)
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{
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struct sysinfo si;
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unsigned long gb;
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si_meminfo(&si);
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/*
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* Calculate the number of pool pages:
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*
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* Convert totalram (nr of pages) to MiB and round to the next
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* GiB. Shift MiB to Gib and multiply the result by
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* POOL_PAGES_PER_GB:
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*/
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if (debug_pagealloc) {
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gb = ((si.totalram >> SHIFT_MB) + ROUND_MB_GB) >> SHIFT_MB_GB;
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pool_size = POOL_PAGES_PER_GB * gb;
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} else {
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pool_size = 1;
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}
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pool_low = pool_size;
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cpa_fill_pool(NULL);
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printk(KERN_DEBUG
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"CPA: page pool initialized %lu of %lu pages preallocated\n",
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pool_pages, pool_size);
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}
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static int split_large_page(pte_t *kpte, unsigned long address)
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{
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unsigned long flags, pfn, pfninc = 1;
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unsigned int i, level;
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pte_t *pbase, *tmp;
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pgprot_t ref_prot;
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struct page *base;
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/*
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* Get a page from the pool. The pool list is protected by the
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* pgd_lock, which we have to take anyway for the split
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* operation:
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*/
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spin_lock_irqsave(&pgd_lock, flags);
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if (list_empty(&page_pool)) {
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spin_unlock_irqrestore(&pgd_lock, flags);
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base = NULL;
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cpa_fill_pool(&base);
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if (!base)
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return -ENOMEM;
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spin_lock_irqsave(&pgd_lock, flags);
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} else {
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base = list_first_entry(&page_pool, struct page, lru);
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list_del(&base->lru);
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pool_pages--;
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if (pool_pages < pool_low)
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pool_low = pool_pages;
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}
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|
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/*
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* Check for races, another CPU might have split this page
|
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* up for us already:
|
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*/
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tmp = lookup_address(address, &level);
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if (tmp != kpte)
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goto out_unlock;
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pbase = (pte_t *)page_address(base);
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#ifdef CONFIG_X86_32
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paravirt_alloc_pt(&init_mm, page_to_pfn(base));
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#endif
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ref_prot = pte_pgprot(pte_clrhuge(*kpte));
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|
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#ifdef CONFIG_X86_64
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if (level == PG_LEVEL_1G) {
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pfninc = PMD_PAGE_SIZE >> PAGE_SHIFT;
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pgprot_val(ref_prot) |= _PAGE_PSE;
|
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}
|
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#endif
|
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|
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/*
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* Get the target pfn from the original entry:
|
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*/
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pfn = pte_pfn(*kpte);
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for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc)
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set_pte(&pbase[i], pfn_pte(pfn, ref_prot));
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|
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/*
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* Install the new, split up pagetable. Important details here:
|
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*
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* On Intel the NX bit of all levels must be cleared to make a
|
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* page executable. See section 4.13.2 of Intel 64 and IA-32
|
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* Architectures Software Developer's Manual).
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*
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* Mark the entry present. The current mapping might be
|
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* set to not present, which we preserved above.
|
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*/
|
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ref_prot = pte_pgprot(pte_mkexec(pte_clrhuge(*kpte)));
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pgprot_val(ref_prot) |= _PAGE_PRESENT;
|
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__set_pmd_pte(kpte, address, mk_pte(base, ref_prot));
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base = NULL;
|
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|
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out_unlock:
|
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/*
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* If we dropped out via the lookup_address check under
|
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* pgd_lock then stick the page back into the pool:
|
|
*/
|
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if (base) {
|
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list_add(&base->lru, &page_pool);
|
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pool_pages++;
|
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} else
|
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pool_used++;
|
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spin_unlock_irqrestore(&pgd_lock, flags);
|
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|
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return 0;
|
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}
|
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|
|
static int __change_page_attr(struct cpa_data *cpa, int primary)
|
|
{
|
|
unsigned long address = cpa->vaddr;
|
|
int do_split, err;
|
|
unsigned int level;
|
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pte_t *kpte, old_pte;
|
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|
|
repeat:
|
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kpte = lookup_address(address, &level);
|
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if (!kpte)
|
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return primary ? -EINVAL : 0;
|
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|
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old_pte = *kpte;
|
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if (!pte_val(old_pte)) {
|
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if (!primary)
|
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return 0;
|
|
printk(KERN_WARNING "CPA: called for zero pte. "
|
|
"vaddr = %lx cpa->vaddr = %lx\n", address,
|
|
cpa->vaddr);
|
|
WARN_ON(1);
|
|
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;
|
|
|
|
/*
|
|
* No need to redo, when the primary call touched the direct
|
|
* mapping already:
|
|
*/
|
|
if (!within(cpa->vaddr, PAGE_OFFSET,
|
|
PAGE_OFFSET + (max_pfn_mapped << PAGE_SHIFT))) {
|
|
|
|
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)
|
|
{
|
|
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))
|
|
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;
|
|
|
|
/* 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));
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
int set_memory_uc(unsigned long addr, int numpages)
|
|
{
|
|
return change_page_attr_set(addr, numpages,
|
|
__pgprot(_PAGE_PCD));
|
|
}
|
|
EXPORT_SYMBOL(set_memory_uc);
|
|
|
|
int set_memory_wb(unsigned long addr, int numpages)
|
|
{
|
|
return change_page_attr_clear(addr, numpages,
|
|
__pgprot(_PAGE_PCD | _PAGE_PWT));
|
|
}
|
|
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));
|
|
}
|
|
|
|
int set_memory_rw(unsigned long addr, int numpages)
|
|
{
|
|
return change_page_attr_set(addr, numpages, __pgprot(_PAGE_RW));
|
|
}
|
|
|
|
int set_memory_np(unsigned long addr, int numpages)
|
|
{
|
|
return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_PRESENT));
|
|
}
|
|
|
|
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_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
|