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1067 lines
27 KiB
1067 lines
27 KiB
/*
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* PPC64 (POWER4) Huge TLB Page Support for Kernel.
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*
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* Copyright (C) 2003 David Gibson, IBM Corporation.
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*
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* Based on the IA-32 version:
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* Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
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*/
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#include <linux/init.h>
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/pagemap.h>
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#include <linux/smp_lock.h>
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#include <linux/slab.h>
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#include <linux/err.h>
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#include <linux/sysctl.h>
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#include <asm/mman.h>
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#include <asm/pgalloc.h>
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#include <asm/tlb.h>
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#include <asm/tlbflush.h>
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#include <asm/mmu_context.h>
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#include <asm/machdep.h>
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#include <asm/cputable.h>
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#include <asm/tlb.h>
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#include <linux/sysctl.h>
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#define NUM_LOW_AREAS (0x100000000UL >> SID_SHIFT)
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#define NUM_HIGH_AREAS (PGTABLE_RANGE >> HTLB_AREA_SHIFT)
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#ifdef CONFIG_PPC_64K_PAGES
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#define HUGEPTE_INDEX_SIZE (PMD_SHIFT-HPAGE_SHIFT)
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#else
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#define HUGEPTE_INDEX_SIZE (PUD_SHIFT-HPAGE_SHIFT)
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#endif
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#define PTRS_PER_HUGEPTE (1 << HUGEPTE_INDEX_SIZE)
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#define HUGEPTE_TABLE_SIZE (sizeof(pte_t) << HUGEPTE_INDEX_SIZE)
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#define HUGEPD_SHIFT (HPAGE_SHIFT + HUGEPTE_INDEX_SIZE)
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#define HUGEPD_SIZE (1UL << HUGEPD_SHIFT)
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#define HUGEPD_MASK (~(HUGEPD_SIZE-1))
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#define huge_pgtable_cache (pgtable_cache[HUGEPTE_CACHE_NUM])
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/* Flag to mark huge PD pointers. This means pmd_bad() and pud_bad()
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* will choke on pointers to hugepte tables, which is handy for
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* catching screwups early. */
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#define HUGEPD_OK 0x1
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typedef struct { unsigned long pd; } hugepd_t;
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#define hugepd_none(hpd) ((hpd).pd == 0)
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static inline pte_t *hugepd_page(hugepd_t hpd)
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{
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BUG_ON(!(hpd.pd & HUGEPD_OK));
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return (pte_t *)(hpd.pd & ~HUGEPD_OK);
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}
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static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr)
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{
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unsigned long idx = ((addr >> HPAGE_SHIFT) & (PTRS_PER_HUGEPTE-1));
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pte_t *dir = hugepd_page(*hpdp);
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return dir + idx;
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}
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static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
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unsigned long address)
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{
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pte_t *new = kmem_cache_alloc(huge_pgtable_cache,
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GFP_KERNEL|__GFP_REPEAT);
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if (! new)
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return -ENOMEM;
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spin_lock(&mm->page_table_lock);
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if (!hugepd_none(*hpdp))
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kmem_cache_free(huge_pgtable_cache, new);
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else
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hpdp->pd = (unsigned long)new | HUGEPD_OK;
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spin_unlock(&mm->page_table_lock);
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return 0;
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}
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/* Modelled after find_linux_pte() */
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pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
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{
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pgd_t *pg;
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pud_t *pu;
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BUG_ON(! in_hugepage_area(mm->context, addr));
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addr &= HPAGE_MASK;
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pg = pgd_offset(mm, addr);
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if (!pgd_none(*pg)) {
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pu = pud_offset(pg, addr);
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if (!pud_none(*pu)) {
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#ifdef CONFIG_PPC_64K_PAGES
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pmd_t *pm;
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pm = pmd_offset(pu, addr);
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if (!pmd_none(*pm))
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return hugepte_offset((hugepd_t *)pm, addr);
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#else
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return hugepte_offset((hugepd_t *)pu, addr);
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#endif
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}
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}
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return NULL;
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}
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pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
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{
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pgd_t *pg;
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pud_t *pu;
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hugepd_t *hpdp = NULL;
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BUG_ON(! in_hugepage_area(mm->context, addr));
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addr &= HPAGE_MASK;
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pg = pgd_offset(mm, addr);
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pu = pud_alloc(mm, pg, addr);
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if (pu) {
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#ifdef CONFIG_PPC_64K_PAGES
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pmd_t *pm;
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pm = pmd_alloc(mm, pu, addr);
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if (pm)
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hpdp = (hugepd_t *)pm;
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#else
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hpdp = (hugepd_t *)pu;
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#endif
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}
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if (! hpdp)
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return NULL;
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if (hugepd_none(*hpdp) && __hugepte_alloc(mm, hpdp, addr))
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return NULL;
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return hugepte_offset(hpdp, addr);
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}
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static void free_hugepte_range(struct mmu_gather *tlb, hugepd_t *hpdp)
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{
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pte_t *hugepte = hugepd_page(*hpdp);
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hpdp->pd = 0;
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tlb->need_flush = 1;
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pgtable_free_tlb(tlb, pgtable_free_cache(hugepte, HUGEPTE_CACHE_NUM,
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PGF_CACHENUM_MASK));
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}
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#ifdef CONFIG_PPC_64K_PAGES
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static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
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unsigned long addr, unsigned long end,
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unsigned long floor, unsigned long ceiling)
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{
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pmd_t *pmd;
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unsigned long next;
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unsigned long start;
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start = addr;
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pmd = pmd_offset(pud, addr);
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do {
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next = pmd_addr_end(addr, end);
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if (pmd_none(*pmd))
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continue;
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free_hugepte_range(tlb, (hugepd_t *)pmd);
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} while (pmd++, addr = next, addr != end);
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start &= PUD_MASK;
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if (start < floor)
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return;
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if (ceiling) {
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ceiling &= PUD_MASK;
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if (!ceiling)
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return;
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}
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if (end - 1 > ceiling - 1)
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return;
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pmd = pmd_offset(pud, start);
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pud_clear(pud);
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pmd_free_tlb(tlb, pmd);
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}
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#endif
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static void hugetlb_free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
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unsigned long addr, unsigned long end,
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unsigned long floor, unsigned long ceiling)
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{
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pud_t *pud;
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unsigned long next;
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unsigned long start;
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start = addr;
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pud = pud_offset(pgd, addr);
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do {
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next = pud_addr_end(addr, end);
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#ifdef CONFIG_PPC_64K_PAGES
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if (pud_none_or_clear_bad(pud))
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continue;
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hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
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#else
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if (pud_none(*pud))
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continue;
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free_hugepte_range(tlb, (hugepd_t *)pud);
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#endif
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} while (pud++, addr = next, addr != end);
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start &= PGDIR_MASK;
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if (start < floor)
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return;
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if (ceiling) {
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ceiling &= PGDIR_MASK;
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if (!ceiling)
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return;
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}
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if (end - 1 > ceiling - 1)
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return;
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pud = pud_offset(pgd, start);
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pgd_clear(pgd);
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pud_free_tlb(tlb, pud);
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}
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/*
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* This function frees user-level page tables of a process.
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*
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* Must be called with pagetable lock held.
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*/
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void hugetlb_free_pgd_range(struct mmu_gather **tlb,
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unsigned long addr, unsigned long end,
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unsigned long floor, unsigned long ceiling)
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{
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pgd_t *pgd;
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unsigned long next;
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unsigned long start;
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/*
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* Comments below take from the normal free_pgd_range(). They
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* apply here too. The tests against HUGEPD_MASK below are
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* essential, because we *don't* test for this at the bottom
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* level. Without them we'll attempt to free a hugepte table
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* when we unmap just part of it, even if there are other
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* active mappings using it.
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*
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* The next few lines have given us lots of grief...
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*
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* Why are we testing HUGEPD* at this top level? Because
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* often there will be no work to do at all, and we'd prefer
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* not to go all the way down to the bottom just to discover
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* that.
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*
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* Why all these "- 1"s? Because 0 represents both the bottom
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* of the address space and the top of it (using -1 for the
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* top wouldn't help much: the masks would do the wrong thing).
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* The rule is that addr 0 and floor 0 refer to the bottom of
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* the address space, but end 0 and ceiling 0 refer to the top
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* Comparisons need to use "end - 1" and "ceiling - 1" (though
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* that end 0 case should be mythical).
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*
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* Wherever addr is brought up or ceiling brought down, we
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* must be careful to reject "the opposite 0" before it
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* confuses the subsequent tests. But what about where end is
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* brought down by HUGEPD_SIZE below? no, end can't go down to
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* 0 there.
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*
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* Whereas we round start (addr) and ceiling down, by different
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* masks at different levels, in order to test whether a table
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* now has no other vmas using it, so can be freed, we don't
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* bother to round floor or end up - the tests don't need that.
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*/
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addr &= HUGEPD_MASK;
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if (addr < floor) {
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addr += HUGEPD_SIZE;
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if (!addr)
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return;
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}
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if (ceiling) {
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ceiling &= HUGEPD_MASK;
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if (!ceiling)
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return;
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}
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if (end - 1 > ceiling - 1)
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end -= HUGEPD_SIZE;
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if (addr > end - 1)
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return;
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start = addr;
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pgd = pgd_offset((*tlb)->mm, addr);
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do {
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BUG_ON(! in_hugepage_area((*tlb)->mm->context, addr));
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next = pgd_addr_end(addr, end);
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if (pgd_none_or_clear_bad(pgd))
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continue;
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hugetlb_free_pud_range(*tlb, pgd, addr, next, floor, ceiling);
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} while (pgd++, addr = next, addr != end);
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}
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void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
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pte_t *ptep, pte_t pte)
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{
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if (pte_present(*ptep)) {
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/* We open-code pte_clear because we need to pass the right
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* argument to hpte_update (huge / !huge)
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*/
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unsigned long old = pte_update(ptep, ~0UL);
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if (old & _PAGE_HASHPTE)
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hpte_update(mm, addr & HPAGE_MASK, ptep, old, 1);
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flush_tlb_pending();
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}
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*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
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}
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pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
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pte_t *ptep)
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{
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unsigned long old = pte_update(ptep, ~0UL);
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if (old & _PAGE_HASHPTE)
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hpte_update(mm, addr & HPAGE_MASK, ptep, old, 1);
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*ptep = __pte(0);
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return __pte(old);
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}
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struct slb_flush_info {
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struct mm_struct *mm;
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u16 newareas;
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};
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static void flush_low_segments(void *parm)
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{
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struct slb_flush_info *fi = parm;
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unsigned long i;
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BUILD_BUG_ON((sizeof(fi->newareas)*8) != NUM_LOW_AREAS);
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if (current->active_mm != fi->mm)
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return;
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/* Only need to do anything if this CPU is working in the same
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* mm as the one which has changed */
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/* update the paca copy of the context struct */
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get_paca()->context = current->active_mm->context;
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asm volatile("isync" : : : "memory");
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for (i = 0; i < NUM_LOW_AREAS; i++) {
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if (! (fi->newareas & (1U << i)))
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continue;
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asm volatile("slbie %0"
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: : "r" ((i << SID_SHIFT) | SLBIE_C));
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}
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asm volatile("isync" : : : "memory");
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}
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static void flush_high_segments(void *parm)
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{
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struct slb_flush_info *fi = parm;
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unsigned long i, j;
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BUILD_BUG_ON((sizeof(fi->newareas)*8) != NUM_HIGH_AREAS);
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if (current->active_mm != fi->mm)
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return;
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/* Only need to do anything if this CPU is working in the same
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* mm as the one which has changed */
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/* update the paca copy of the context struct */
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get_paca()->context = current->active_mm->context;
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asm volatile("isync" : : : "memory");
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for (i = 0; i < NUM_HIGH_AREAS; i++) {
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if (! (fi->newareas & (1U << i)))
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continue;
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for (j = 0; j < (1UL << (HTLB_AREA_SHIFT-SID_SHIFT)); j++)
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asm volatile("slbie %0"
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:: "r" (((i << HTLB_AREA_SHIFT)
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+ (j << SID_SHIFT)) | SLBIE_C));
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}
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asm volatile("isync" : : : "memory");
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}
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static int prepare_low_area_for_htlb(struct mm_struct *mm, unsigned long area)
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{
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unsigned long start = area << SID_SHIFT;
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unsigned long end = (area+1) << SID_SHIFT;
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struct vm_area_struct *vma;
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BUG_ON(area >= NUM_LOW_AREAS);
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/* Check no VMAs are in the region */
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vma = find_vma(mm, start);
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if (vma && (vma->vm_start < end))
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return -EBUSY;
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return 0;
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}
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static int prepare_high_area_for_htlb(struct mm_struct *mm, unsigned long area)
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{
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unsigned long start = area << HTLB_AREA_SHIFT;
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unsigned long end = (area+1) << HTLB_AREA_SHIFT;
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struct vm_area_struct *vma;
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BUG_ON(area >= NUM_HIGH_AREAS);
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/* Hack, so that each addresses is controlled by exactly one
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* of the high or low area bitmaps, the first high area starts
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* at 4GB, not 0 */
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if (start == 0)
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start = 0x100000000UL;
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|
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/* Check no VMAs are in the region */
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vma = find_vma(mm, start);
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if (vma && (vma->vm_start < end))
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return -EBUSY;
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return 0;
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}
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|
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static int open_low_hpage_areas(struct mm_struct *mm, u16 newareas)
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{
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unsigned long i;
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struct slb_flush_info fi;
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|
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BUILD_BUG_ON((sizeof(newareas)*8) != NUM_LOW_AREAS);
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BUILD_BUG_ON((sizeof(mm->context.low_htlb_areas)*8) != NUM_LOW_AREAS);
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newareas &= ~(mm->context.low_htlb_areas);
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if (! newareas)
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return 0; /* The segments we want are already open */
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for (i = 0; i < NUM_LOW_AREAS; i++)
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if ((1 << i) & newareas)
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if (prepare_low_area_for_htlb(mm, i) != 0)
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return -EBUSY;
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mm->context.low_htlb_areas |= newareas;
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|
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/* the context change must make it to memory before the flush,
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* so that further SLB misses do the right thing. */
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mb();
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fi.mm = mm;
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fi.newareas = newareas;
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on_each_cpu(flush_low_segments, &fi, 0, 1);
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|
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return 0;
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}
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|
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static int open_high_hpage_areas(struct mm_struct *mm, u16 newareas)
|
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{
|
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struct slb_flush_info fi;
|
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unsigned long i;
|
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|
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BUILD_BUG_ON((sizeof(newareas)*8) != NUM_HIGH_AREAS);
|
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BUILD_BUG_ON((sizeof(mm->context.high_htlb_areas)*8)
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!= NUM_HIGH_AREAS);
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|
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newareas &= ~(mm->context.high_htlb_areas);
|
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if (! newareas)
|
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return 0; /* The areas we want are already open */
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|
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for (i = 0; i < NUM_HIGH_AREAS; i++)
|
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if ((1 << i) & newareas)
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if (prepare_high_area_for_htlb(mm, i) != 0)
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return -EBUSY;
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|
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mm->context.high_htlb_areas |= newareas;
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|
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/* the context change must make it to memory before the flush,
|
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* so that further SLB misses do the right thing. */
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mb();
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|
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fi.mm = mm;
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fi.newareas = newareas;
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on_each_cpu(flush_high_segments, &fi, 0, 1);
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|
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return 0;
|
|
}
|
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|
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int prepare_hugepage_range(unsigned long addr, unsigned long len, pgoff_t pgoff)
|
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{
|
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int err = 0;
|
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|
|
if (pgoff & (~HPAGE_MASK >> PAGE_SHIFT))
|
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return -EINVAL;
|
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if (len & ~HPAGE_MASK)
|
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return -EINVAL;
|
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if (addr & ~HPAGE_MASK)
|
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return -EINVAL;
|
|
|
|
if (addr < 0x100000000UL)
|
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err = open_low_hpage_areas(current->mm,
|
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LOW_ESID_MASK(addr, len));
|
|
if ((addr + len) > 0x100000000UL)
|
|
err = open_high_hpage_areas(current->mm,
|
|
HTLB_AREA_MASK(addr, len));
|
|
if (err) {
|
|
printk(KERN_DEBUG "prepare_hugepage_range(%lx, %lx)"
|
|
" failed (lowmask: 0x%04hx, highmask: 0x%04hx)\n",
|
|
addr, len,
|
|
LOW_ESID_MASK(addr, len), HTLB_AREA_MASK(addr, len));
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct page *
|
|
follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
|
|
{
|
|
pte_t *ptep;
|
|
struct page *page;
|
|
|
|
if (! in_hugepage_area(mm->context, address))
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
ptep = huge_pte_offset(mm, address);
|
|
page = pte_page(*ptep);
|
|
if (page)
|
|
page += (address % HPAGE_SIZE) / PAGE_SIZE;
|
|
|
|
return page;
|
|
}
|
|
|
|
int pmd_huge(pmd_t pmd)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
struct page *
|
|
follow_huge_pmd(struct mm_struct *mm, unsigned long address,
|
|
pmd_t *pmd, int write)
|
|
{
|
|
BUG();
|
|
return NULL;
|
|
}
|
|
|
|
/* Because we have an exclusive hugepage region which lies within the
|
|
* normal user address space, we have to take special measures to make
|
|
* non-huge mmap()s evade the hugepage reserved regions. */
|
|
unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
|
|
unsigned long len, unsigned long pgoff,
|
|
unsigned long flags)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
struct vm_area_struct *vma;
|
|
unsigned long start_addr;
|
|
|
|
if (len > TASK_SIZE)
|
|
return -ENOMEM;
|
|
|
|
if (addr) {
|
|
addr = PAGE_ALIGN(addr);
|
|
vma = find_vma(mm, addr);
|
|
if (((TASK_SIZE - len) >= addr)
|
|
&& (!vma || (addr+len) <= vma->vm_start)
|
|
&& !is_hugepage_only_range(mm, addr,len))
|
|
return addr;
|
|
}
|
|
if (len > mm->cached_hole_size) {
|
|
start_addr = addr = mm->free_area_cache;
|
|
} else {
|
|
start_addr = addr = TASK_UNMAPPED_BASE;
|
|
mm->cached_hole_size = 0;
|
|
}
|
|
|
|
full_search:
|
|
vma = find_vma(mm, addr);
|
|
while (TASK_SIZE - len >= addr) {
|
|
BUG_ON(vma && (addr >= vma->vm_end));
|
|
|
|
if (touches_hugepage_low_range(mm, addr, len)) {
|
|
addr = ALIGN(addr+1, 1<<SID_SHIFT);
|
|
vma = find_vma(mm, addr);
|
|
continue;
|
|
}
|
|
if (touches_hugepage_high_range(mm, addr, len)) {
|
|
addr = ALIGN(addr+1, 1UL<<HTLB_AREA_SHIFT);
|
|
vma = find_vma(mm, addr);
|
|
continue;
|
|
}
|
|
if (!vma || addr + len <= vma->vm_start) {
|
|
/*
|
|
* Remember the place where we stopped the search:
|
|
*/
|
|
mm->free_area_cache = addr + len;
|
|
return addr;
|
|
}
|
|
if (addr + mm->cached_hole_size < vma->vm_start)
|
|
mm->cached_hole_size = vma->vm_start - addr;
|
|
addr = vma->vm_end;
|
|
vma = vma->vm_next;
|
|
}
|
|
|
|
/* Make sure we didn't miss any holes */
|
|
if (start_addr != TASK_UNMAPPED_BASE) {
|
|
start_addr = addr = TASK_UNMAPPED_BASE;
|
|
mm->cached_hole_size = 0;
|
|
goto full_search;
|
|
}
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* This mmap-allocator allocates new areas top-down from below the
|
|
* stack's low limit (the base):
|
|
*
|
|
* Because we have an exclusive hugepage region which lies within the
|
|
* normal user address space, we have to take special measures to make
|
|
* non-huge mmap()s evade the hugepage reserved regions.
|
|
*/
|
|
unsigned long
|
|
arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
|
|
const unsigned long len, const unsigned long pgoff,
|
|
const unsigned long flags)
|
|
{
|
|
struct vm_area_struct *vma, *prev_vma;
|
|
struct mm_struct *mm = current->mm;
|
|
unsigned long base = mm->mmap_base, addr = addr0;
|
|
unsigned long largest_hole = mm->cached_hole_size;
|
|
int first_time = 1;
|
|
|
|
/* requested length too big for entire address space */
|
|
if (len > TASK_SIZE)
|
|
return -ENOMEM;
|
|
|
|
/* dont allow allocations above current base */
|
|
if (mm->free_area_cache > base)
|
|
mm->free_area_cache = base;
|
|
|
|
/* requesting a specific address */
|
|
if (addr) {
|
|
addr = PAGE_ALIGN(addr);
|
|
vma = find_vma(mm, addr);
|
|
if (TASK_SIZE - len >= addr &&
|
|
(!vma || addr + len <= vma->vm_start)
|
|
&& !is_hugepage_only_range(mm, addr,len))
|
|
return addr;
|
|
}
|
|
|
|
if (len <= largest_hole) {
|
|
largest_hole = 0;
|
|
mm->free_area_cache = base;
|
|
}
|
|
try_again:
|
|
/* make sure it can fit in the remaining address space */
|
|
if (mm->free_area_cache < len)
|
|
goto fail;
|
|
|
|
/* either no address requested or cant fit in requested address hole */
|
|
addr = (mm->free_area_cache - len) & PAGE_MASK;
|
|
do {
|
|
hugepage_recheck:
|
|
if (touches_hugepage_low_range(mm, addr, len)) {
|
|
addr = (addr & ((~0) << SID_SHIFT)) - len;
|
|
goto hugepage_recheck;
|
|
} else if (touches_hugepage_high_range(mm, addr, len)) {
|
|
addr = (addr & ((~0UL) << HTLB_AREA_SHIFT)) - len;
|
|
goto hugepage_recheck;
|
|
}
|
|
|
|
/*
|
|
* Lookup failure means no vma is above this address,
|
|
* i.e. return with success:
|
|
*/
|
|
if (!(vma = find_vma_prev(mm, addr, &prev_vma)))
|
|
return addr;
|
|
|
|
/*
|
|
* new region fits between prev_vma->vm_end and
|
|
* vma->vm_start, use it:
|
|
*/
|
|
if (addr+len <= vma->vm_start &&
|
|
(!prev_vma || (addr >= prev_vma->vm_end))) {
|
|
/* remember the address as a hint for next time */
|
|
mm->cached_hole_size = largest_hole;
|
|
return (mm->free_area_cache = addr);
|
|
} else {
|
|
/* pull free_area_cache down to the first hole */
|
|
if (mm->free_area_cache == vma->vm_end) {
|
|
mm->free_area_cache = vma->vm_start;
|
|
mm->cached_hole_size = largest_hole;
|
|
}
|
|
}
|
|
|
|
/* remember the largest hole we saw so far */
|
|
if (addr + largest_hole < vma->vm_start)
|
|
largest_hole = vma->vm_start - addr;
|
|
|
|
/* try just below the current vma->vm_start */
|
|
addr = vma->vm_start-len;
|
|
} while (len <= vma->vm_start);
|
|
|
|
fail:
|
|
/*
|
|
* if hint left us with no space for the requested
|
|
* mapping then try again:
|
|
*/
|
|
if (first_time) {
|
|
mm->free_area_cache = base;
|
|
largest_hole = 0;
|
|
first_time = 0;
|
|
goto try_again;
|
|
}
|
|
/*
|
|
* A failed mmap() very likely causes application failure,
|
|
* so fall back to the bottom-up function here. This scenario
|
|
* can happen with large stack limits and large mmap()
|
|
* allocations.
|
|
*/
|
|
mm->free_area_cache = TASK_UNMAPPED_BASE;
|
|
mm->cached_hole_size = ~0UL;
|
|
addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
|
|
/*
|
|
* Restore the topdown base:
|
|
*/
|
|
mm->free_area_cache = base;
|
|
mm->cached_hole_size = ~0UL;
|
|
|
|
return addr;
|
|
}
|
|
|
|
static int htlb_check_hinted_area(unsigned long addr, unsigned long len)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
|
|
vma = find_vma(current->mm, addr);
|
|
if (!vma || ((addr + len) <= vma->vm_start))
|
|
return 0;
|
|
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static unsigned long htlb_get_low_area(unsigned long len, u16 segmask)
|
|
{
|
|
unsigned long addr = 0;
|
|
struct vm_area_struct *vma;
|
|
|
|
vma = find_vma(current->mm, addr);
|
|
while (addr + len <= 0x100000000UL) {
|
|
BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
|
|
|
|
if (! __within_hugepage_low_range(addr, len, segmask)) {
|
|
addr = ALIGN(addr+1, 1<<SID_SHIFT);
|
|
vma = find_vma(current->mm, addr);
|
|
continue;
|
|
}
|
|
|
|
if (!vma || (addr + len) <= vma->vm_start)
|
|
return addr;
|
|
addr = ALIGN(vma->vm_end, HPAGE_SIZE);
|
|
/* Depending on segmask this might not be a confirmed
|
|
* hugepage region, so the ALIGN could have skipped
|
|
* some VMAs */
|
|
vma = find_vma(current->mm, addr);
|
|
}
|
|
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static unsigned long htlb_get_high_area(unsigned long len, u16 areamask)
|
|
{
|
|
unsigned long addr = 0x100000000UL;
|
|
struct vm_area_struct *vma;
|
|
|
|
vma = find_vma(current->mm, addr);
|
|
while (addr + len <= TASK_SIZE_USER64) {
|
|
BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
|
|
|
|
if (! __within_hugepage_high_range(addr, len, areamask)) {
|
|
addr = ALIGN(addr+1, 1UL<<HTLB_AREA_SHIFT);
|
|
vma = find_vma(current->mm, addr);
|
|
continue;
|
|
}
|
|
|
|
if (!vma || (addr + len) <= vma->vm_start)
|
|
return addr;
|
|
addr = ALIGN(vma->vm_end, HPAGE_SIZE);
|
|
/* Depending on segmask this might not be a confirmed
|
|
* hugepage region, so the ALIGN could have skipped
|
|
* some VMAs */
|
|
vma = find_vma(current->mm, addr);
|
|
}
|
|
|
|
return -ENOMEM;
|
|
}
|
|
|
|
unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
|
|
unsigned long len, unsigned long pgoff,
|
|
unsigned long flags)
|
|
{
|
|
int lastshift;
|
|
u16 areamask, curareas;
|
|
|
|
if (HPAGE_SHIFT == 0)
|
|
return -EINVAL;
|
|
if (len & ~HPAGE_MASK)
|
|
return -EINVAL;
|
|
|
|
if (!cpu_has_feature(CPU_FTR_16M_PAGE))
|
|
return -EINVAL;
|
|
|
|
/* Paranoia, caller should have dealt with this */
|
|
BUG_ON((addr + len) < addr);
|
|
|
|
if (test_thread_flag(TIF_32BIT)) {
|
|
/* Paranoia, caller should have dealt with this */
|
|
BUG_ON((addr + len) > 0x100000000UL);
|
|
|
|
curareas = current->mm->context.low_htlb_areas;
|
|
|
|
/* First see if we can use the hint address */
|
|
if (addr && (htlb_check_hinted_area(addr, len) == 0)) {
|
|
areamask = LOW_ESID_MASK(addr, len);
|
|
if (open_low_hpage_areas(current->mm, areamask) == 0)
|
|
return addr;
|
|
}
|
|
|
|
/* Next see if we can map in the existing low areas */
|
|
addr = htlb_get_low_area(len, curareas);
|
|
if (addr != -ENOMEM)
|
|
return addr;
|
|
|
|
/* Finally go looking for areas to open */
|
|
lastshift = 0;
|
|
for (areamask = LOW_ESID_MASK(0x100000000UL-len, len);
|
|
! lastshift; areamask >>=1) {
|
|
if (areamask & 1)
|
|
lastshift = 1;
|
|
|
|
addr = htlb_get_low_area(len, curareas | areamask);
|
|
if ((addr != -ENOMEM)
|
|
&& open_low_hpage_areas(current->mm, areamask) == 0)
|
|
return addr;
|
|
}
|
|
} else {
|
|
curareas = current->mm->context.high_htlb_areas;
|
|
|
|
/* First see if we can use the hint address */
|
|
/* We discourage 64-bit processes from doing hugepage
|
|
* mappings below 4GB (must use MAP_FIXED) */
|
|
if ((addr >= 0x100000000UL)
|
|
&& (htlb_check_hinted_area(addr, len) == 0)) {
|
|
areamask = HTLB_AREA_MASK(addr, len);
|
|
if (open_high_hpage_areas(current->mm, areamask) == 0)
|
|
return addr;
|
|
}
|
|
|
|
/* Next see if we can map in the existing high areas */
|
|
addr = htlb_get_high_area(len, curareas);
|
|
if (addr != -ENOMEM)
|
|
return addr;
|
|
|
|
/* Finally go looking for areas to open */
|
|
lastshift = 0;
|
|
for (areamask = HTLB_AREA_MASK(TASK_SIZE_USER64-len, len);
|
|
! lastshift; areamask >>=1) {
|
|
if (areamask & 1)
|
|
lastshift = 1;
|
|
|
|
addr = htlb_get_high_area(len, curareas | areamask);
|
|
if ((addr != -ENOMEM)
|
|
&& open_high_hpage_areas(current->mm, areamask) == 0)
|
|
return addr;
|
|
}
|
|
}
|
|
printk(KERN_DEBUG "hugetlb_get_unmapped_area() unable to open"
|
|
" enough areas\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* Called by asm hashtable.S for doing lazy icache flush
|
|
*/
|
|
static unsigned int hash_huge_page_do_lazy_icache(unsigned long rflags,
|
|
pte_t pte, int trap)
|
|
{
|
|
struct page *page;
|
|
int i;
|
|
|
|
if (!pfn_valid(pte_pfn(pte)))
|
|
return rflags;
|
|
|
|
page = pte_page(pte);
|
|
|
|
/* page is dirty */
|
|
if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
|
|
if (trap == 0x400) {
|
|
for (i = 0; i < (HPAGE_SIZE / PAGE_SIZE); i++)
|
|
__flush_dcache_icache(page_address(page+i));
|
|
set_bit(PG_arch_1, &page->flags);
|
|
} else {
|
|
rflags |= HPTE_R_N;
|
|
}
|
|
}
|
|
return rflags;
|
|
}
|
|
|
|
int hash_huge_page(struct mm_struct *mm, unsigned long access,
|
|
unsigned long ea, unsigned long vsid, int local,
|
|
unsigned long trap)
|
|
{
|
|
pte_t *ptep;
|
|
unsigned long old_pte, new_pte;
|
|
unsigned long va, rflags, pa;
|
|
long slot;
|
|
int err = 1;
|
|
|
|
ptep = huge_pte_offset(mm, ea);
|
|
|
|
/* Search the Linux page table for a match with va */
|
|
va = (vsid << 28) | (ea & 0x0fffffff);
|
|
|
|
/*
|
|
* If no pte found or not present, send the problem up to
|
|
* do_page_fault
|
|
*/
|
|
if (unlikely(!ptep || pte_none(*ptep)))
|
|
goto out;
|
|
|
|
/*
|
|
* Check the user's access rights to the page. If access should be
|
|
* prevented then send the problem up to do_page_fault.
|
|
*/
|
|
if (unlikely(access & ~pte_val(*ptep)))
|
|
goto out;
|
|
/*
|
|
* At this point, we have a pte (old_pte) which can be used to build
|
|
* or update an HPTE. There are 2 cases:
|
|
*
|
|
* 1. There is a valid (present) pte with no associated HPTE (this is
|
|
* the most common case)
|
|
* 2. There is a valid (present) pte with an associated HPTE. The
|
|
* current values of the pp bits in the HPTE prevent access
|
|
* because we are doing software DIRTY bit management and the
|
|
* page is currently not DIRTY.
|
|
*/
|
|
|
|
|
|
do {
|
|
old_pte = pte_val(*ptep);
|
|
if (old_pte & _PAGE_BUSY)
|
|
goto out;
|
|
new_pte = old_pte | _PAGE_BUSY |
|
|
_PAGE_ACCESSED | _PAGE_HASHPTE;
|
|
} while(old_pte != __cmpxchg_u64((unsigned long *)ptep,
|
|
old_pte, new_pte));
|
|
|
|
rflags = 0x2 | (!(new_pte & _PAGE_RW));
|
|
/* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */
|
|
rflags |= ((new_pte & _PAGE_EXEC) ? 0 : HPTE_R_N);
|
|
if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
|
|
/* No CPU has hugepages but lacks no execute, so we
|
|
* don't need to worry about that case */
|
|
rflags = hash_huge_page_do_lazy_icache(rflags, __pte(old_pte),
|
|
trap);
|
|
|
|
/* Check if pte already has an hpte (case 2) */
|
|
if (unlikely(old_pte & _PAGE_HASHPTE)) {
|
|
/* There MIGHT be an HPTE for this pte */
|
|
unsigned long hash, slot;
|
|
|
|
hash = hpt_hash(va, HPAGE_SHIFT);
|
|
if (old_pte & _PAGE_F_SECOND)
|
|
hash = ~hash;
|
|
slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
|
|
slot += (old_pte & _PAGE_F_GIX) >> 12;
|
|
|
|
if (ppc_md.hpte_updatepp(slot, rflags, va, mmu_huge_psize,
|
|
local) == -1)
|
|
old_pte &= ~_PAGE_HPTEFLAGS;
|
|
}
|
|
|
|
if (likely(!(old_pte & _PAGE_HASHPTE))) {
|
|
unsigned long hash = hpt_hash(va, HPAGE_SHIFT);
|
|
unsigned long hpte_group;
|
|
|
|
pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
|
|
|
|
repeat:
|
|
hpte_group = ((hash & htab_hash_mask) *
|
|
HPTES_PER_GROUP) & ~0x7UL;
|
|
|
|
/* clear HPTE slot informations in new PTE */
|
|
new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE;
|
|
|
|
/* Add in WIMG bits */
|
|
/* XXX We should store these in the pte */
|
|
/* --BenH: I think they are ... */
|
|
rflags |= _PAGE_COHERENT;
|
|
|
|
/* Insert into the hash table, primary slot */
|
|
slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags, 0,
|
|
mmu_huge_psize);
|
|
|
|
/* Primary is full, try the secondary */
|
|
if (unlikely(slot == -1)) {
|
|
new_pte |= _PAGE_F_SECOND;
|
|
hpte_group = ((~hash & htab_hash_mask) *
|
|
HPTES_PER_GROUP) & ~0x7UL;
|
|
slot = ppc_md.hpte_insert(hpte_group, va, pa, rflags,
|
|
HPTE_V_SECONDARY,
|
|
mmu_huge_psize);
|
|
if (slot == -1) {
|
|
if (mftb() & 0x1)
|
|
hpte_group = ((hash & htab_hash_mask) *
|
|
HPTES_PER_GROUP)&~0x7UL;
|
|
|
|
ppc_md.hpte_remove(hpte_group);
|
|
goto repeat;
|
|
}
|
|
}
|
|
|
|
if (unlikely(slot == -2))
|
|
panic("hash_huge_page: pte_insert failed\n");
|
|
|
|
new_pte |= (slot << 12) & _PAGE_F_GIX;
|
|
}
|
|
|
|
/*
|
|
* No need to use ldarx/stdcx here
|
|
*/
|
|
*ptep = __pte(new_pte & ~_PAGE_BUSY);
|
|
|
|
err = 0;
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void zero_ctor(void *addr, kmem_cache_t *cache, unsigned long flags)
|
|
{
|
|
memset(addr, 0, kmem_cache_size(cache));
|
|
}
|
|
|
|
static int __init hugetlbpage_init(void)
|
|
{
|
|
if (!cpu_has_feature(CPU_FTR_16M_PAGE))
|
|
return -ENODEV;
|
|
|
|
huge_pgtable_cache = kmem_cache_create("hugepte_cache",
|
|
HUGEPTE_TABLE_SIZE,
|
|
HUGEPTE_TABLE_SIZE,
|
|
SLAB_HWCACHE_ALIGN |
|
|
SLAB_MUST_HWCACHE_ALIGN,
|
|
zero_ctor, NULL);
|
|
if (! huge_pgtable_cache)
|
|
panic("hugetlbpage_init(): could not create hugepte cache\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
module_init(hugetlbpage_init);
|
|
|