diff options
Diffstat (limited to 'arch/ppc64/mm/hugetlbpage.c')
| -rw-r--r-- | arch/ppc64/mm/hugetlbpage.c | 704 |
1 files changed, 0 insertions, 704 deletions
diff --git a/arch/ppc64/mm/hugetlbpage.c b/arch/ppc64/mm/hugetlbpage.c deleted file mode 100644 index f9524602818..00000000000 --- a/arch/ppc64/mm/hugetlbpage.c +++ /dev/null @@ -1,704 +0,0 @@ -/* - * PPC64 (POWER4) Huge TLB Page Support for Kernel. - * - * Copyright (C) 2003 David Gibson, IBM Corporation. - * - * Based on the IA-32 version: - * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com> - */ - -#include <linux/init.h> -#include <linux/fs.h> -#include <linux/mm.h> -#include <linux/hugetlb.h> -#include <linux/pagemap.h> -#include <linux/smp_lock.h> -#include <linux/slab.h> -#include <linux/err.h> -#include <linux/sysctl.h> -#include <asm/mman.h> -#include <asm/pgalloc.h> -#include <asm/tlb.h> -#include <asm/tlbflush.h> -#include <asm/mmu_context.h> -#include <asm/machdep.h> -#include <asm/cputable.h> -#include <asm/tlb.h> - -#include <linux/sysctl.h> - -#define HUGEPGDIR_SHIFT (HPAGE_SHIFT + PAGE_SHIFT - 3) -#define HUGEPGDIR_SIZE (1UL << HUGEPGDIR_SHIFT) -#define HUGEPGDIR_MASK (~(HUGEPGDIR_SIZE-1)) - -#define HUGEPTE_INDEX_SIZE 9 -#define HUGEPGD_INDEX_SIZE 10 - -#define PTRS_PER_HUGEPTE (1 << HUGEPTE_INDEX_SIZE) -#define PTRS_PER_HUGEPGD (1 << HUGEPGD_INDEX_SIZE) - -static inline int hugepgd_index(unsigned long addr) -{ - return (addr & ~REGION_MASK) >> HUGEPGDIR_SHIFT; -} - -static pud_t *hugepgd_offset(struct mm_struct *mm, unsigned long addr) -{ - int index; - - if (! mm->context.huge_pgdir) - return NULL; - - - index = hugepgd_index(addr); - BUG_ON(index >= PTRS_PER_HUGEPGD); - return (pud_t *)(mm->context.huge_pgdir + index); -} - -static inline pte_t *hugepte_offset(pud_t *dir, unsigned long addr) -{ - int index; - - if (pud_none(*dir)) - return NULL; - - index = (addr >> HPAGE_SHIFT) % PTRS_PER_HUGEPTE; - return (pte_t *)pud_page(*dir) + index; -} - -static pud_t *hugepgd_alloc(struct mm_struct *mm, unsigned long addr) -{ - BUG_ON(! in_hugepage_area(mm->context, addr)); - - if (! mm->context.huge_pgdir) { - pgd_t *new; - spin_unlock(&mm->page_table_lock); - /* Don't use pgd_alloc(), because we want __GFP_REPEAT */ - new = kmem_cache_alloc(zero_cache, GFP_KERNEL | __GFP_REPEAT); - BUG_ON(memcmp(new, empty_zero_page, PAGE_SIZE)); - spin_lock(&mm->page_table_lock); - - /* - * Because we dropped the lock, we should re-check the - * entry, as somebody else could have populated it.. - */ - if (mm->context.huge_pgdir) - pgd_free(new); - else - mm->context.huge_pgdir = new; - } - return hugepgd_offset(mm, addr); -} - -static pte_t *hugepte_alloc(struct mm_struct *mm, pud_t *dir, unsigned long addr) -{ - if (! pud_present(*dir)) { - pte_t *new; - - spin_unlock(&mm->page_table_lock); - new = kmem_cache_alloc(zero_cache, GFP_KERNEL | __GFP_REPEAT); - BUG_ON(memcmp(new, empty_zero_page, PAGE_SIZE)); - spin_lock(&mm->page_table_lock); - /* - * Because we dropped the lock, we should re-check the - * entry, as somebody else could have populated it.. - */ - if (pud_present(*dir)) { - if (new) - kmem_cache_free(zero_cache, new); - } else { - struct page *ptepage; - - if (! new) - return NULL; - ptepage = virt_to_page(new); - ptepage->mapping = (void *) mm; - ptepage->index = addr & HUGEPGDIR_MASK; - pud_populate(mm, dir, new); - } - } - - return hugepte_offset(dir, addr); -} - -pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) -{ - pud_t *pud; - - BUG_ON(! in_hugepage_area(mm->context, addr)); - - pud = hugepgd_offset(mm, addr); - if (! pud) - return NULL; - - return hugepte_offset(pud, addr); -} - -pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr) -{ - pud_t *pud; - - BUG_ON(! in_hugepage_area(mm->context, addr)); - - pud = hugepgd_alloc(mm, addr); - if (! pud) - return NULL; - - return hugepte_alloc(mm, pud, addr); -} - -/* - * This function checks for proper alignment of input addr and len parameters. - */ -int is_aligned_hugepage_range(unsigned long addr, unsigned long len) -{ - if (len & ~HPAGE_MASK) - return -EINVAL; - if (addr & ~HPAGE_MASK) - return -EINVAL; - if (! (within_hugepage_low_range(addr, len) - || within_hugepage_high_range(addr, len)) ) - return -EINVAL; - return 0; -} - -static void flush_segments(void *parm) -{ - u16 segs = (unsigned long) parm; - unsigned long i; - - asm volatile("isync" : : : "memory"); - - for (i = 0; i < 16; i++) { - if (! (segs & (1U << i))) - continue; - asm volatile("slbie %0" : : "r" (i << SID_SHIFT)); - } - - asm volatile("isync" : : : "memory"); -} - -static int prepare_low_seg_for_htlb(struct mm_struct *mm, unsigned long seg) -{ - unsigned long start = seg << SID_SHIFT; - unsigned long end = (seg+1) << SID_SHIFT; - struct vm_area_struct *vma; - - BUG_ON(seg >= 16); - - /* Check no VMAs are in the region */ - vma = find_vma(mm, start); - if (vma && (vma->vm_start < end)) - return -EBUSY; - - return 0; -} - -static int open_low_hpage_segs(struct mm_struct *mm, u16 newsegs) -{ - unsigned long i; - - newsegs &= ~(mm->context.htlb_segs); - if (! newsegs) - return 0; /* The segments we want are already open */ - - for (i = 0; i < 16; i++) - if ((1 << i) & newsegs) - if (prepare_low_seg_for_htlb(mm, i) != 0) - return -EBUSY; - - mm->context.htlb_segs |= newsegs; - - /* update the paca copy of the context struct */ - get_paca()->context = mm->context; - - /* the context change must make it to memory before the flush, - * so that further SLB misses do the right thing. */ - mb(); - on_each_cpu(flush_segments, (void *)(unsigned long)newsegs, 0, 1); - - return 0; -} - -int prepare_hugepage_range(unsigned long addr, unsigned long len) -{ - if (within_hugepage_high_range(addr, len)) - return 0; - else if ((addr < 0x100000000UL) && ((addr+len) < 0x100000000UL)) { - int err; - /* Yes, we need both tests, in case addr+len overflows - * 64-bit arithmetic */ - err = open_low_hpage_segs(current->mm, - LOW_ESID_MASK(addr, len)); - if (err) - printk(KERN_DEBUG "prepare_hugepage_range(%lx, %lx)" - " failed (segs: 0x%04hx)\n", addr, len, - LOW_ESID_MASK(addr, len)); - return err; - } - - return -EINVAL; -} - -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(addr, len)) { - addr = TASK_HPAGE_END; - 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(addr, len)) { - addr = TASK_HPAGE_BASE - len; - } - - /* - * 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 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) -{ - unsigned long addr = TASK_HPAGE_BASE; - struct vm_area_struct *vma; - - vma = find_vma(current->mm, addr); - for (vma = find_vma(current->mm, addr); - addr + len <= TASK_HPAGE_END; - vma = vma->vm_next) { - BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */ - BUG_ON(! within_hugepage_high_range(addr, len)); - - if (!vma || (addr + len) <= vma->vm_start) - return addr; - addr = ALIGN(vma->vm_end, HPAGE_SIZE); - /* Because we're in a hugepage region, this alignment - * should not skip us over any VMAs */ - } - - return -ENOMEM; -} - -unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, - unsigned long len, unsigned long pgoff, - unsigned long flags) -{ - if (len & ~HPAGE_MASK) - return -EINVAL; - - if (!cpu_has_feature(CPU_FTR_16M_PAGE)) - return -EINVAL; - - if (test_thread_flag(TIF_32BIT)) { - int lastshift = 0; - u16 segmask, cursegs = current->mm->context.htlb_segs; - - /* First see if we can do the mapping in the existing - * low hpage segments */ - addr = htlb_get_low_area(len, cursegs); - if (addr != -ENOMEM) - return addr; - - for (segmask = LOW_ESID_MASK(0x100000000UL-len, len); - ! lastshift; segmask >>=1) { - if (segmask & 1) - lastshift = 1; - - addr = htlb_get_low_area(len, cursegs | segmask); - if ((addr != -ENOMEM) - && open_low_hpage_segs(current->mm, segmask) == 0) - return addr; - } - printk(KERN_DEBUG "hugetlb_get_unmapped_area() unable to open" - " enough segments\n"); - return -ENOMEM; - } else { - return htlb_get_high_area(len); - } -} - -void hugetlb_mm_free_pgd(struct mm_struct *mm) -{ - int i; - pgd_t *pgdir; - - spin_lock(&mm->page_table_lock); - - pgdir = mm->context.huge_pgdir; - if (! pgdir) - goto out; - - mm->context.huge_pgdir = NULL; - - /* cleanup any hugepte pages leftover */ - for (i = 0; i < PTRS_PER_HUGEPGD; i++) { - pud_t *pud = (pud_t *)(pgdir + i); - - if (! pud_none(*pud)) { - pte_t *pte = (pte_t *)pud_page(*pud); - struct page *ptepage = virt_to_page(pte); - - ptepage->mapping = NULL; - - BUG_ON(memcmp(pte, empty_zero_page, PAGE_SIZE)); - kmem_cache_free(zero_cache, pte); - } - pud_clear(pud); - } - - BUG_ON(memcmp(pgdir, empty_zero_page, PAGE_SIZE)); - kmem_cache_free(zero_cache, pgdir); - - out: - spin_unlock(&mm->page_table_lock); -} - -int hash_huge_page(struct mm_struct *mm, unsigned long access, - unsigned long ea, unsigned long vsid, int local) -{ - pte_t *ptep; - unsigned long va, vpn; - pte_t old_pte, new_pte; - unsigned long rflags, prpn; - long slot; - int err = 1; - - spin_lock(&mm->page_table_lock); - - ptep = huge_pte_offset(mm, ea); - - /* Search the Linux page table for a match with va */ - va = (vsid << 28) | (ea & 0x0fffffff); - vpn = va >> HPAGE_SHIFT; - - /* - * If no pte found or not present, send the problem up to - * do_page_fault - */ - if (unlikely(!ptep || pte_none(*ptep))) - goto out; - -/* BUG_ON(pte_bad(*ptep)); */ - - /* - * 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. - */ - - - old_pte = *ptep; - new_pte = old_pte; - - rflags = 0x2 | (! (pte_val(new_pte) & _PAGE_RW)); - /* _PAGE_EXEC -> HW_NO_EXEC since it's inverted */ - rflags |= ((pte_val(new_pte) & _PAGE_EXEC) ? 0 : HW_NO_EXEC); - - /* Check if pte already has an hpte (case 2) */ - if (unlikely(pte_val(old_pte) & _PAGE_HASHPTE)) { - /* There MIGHT be an HPTE for this pte */ - unsigned long hash, slot; - - hash = hpt_hash(vpn, 1); - if (pte_val(old_pte) & _PAGE_SECONDARY) - hash = ~hash; - slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; - slot += (pte_val(old_pte) & _PAGE_GROUP_IX) >> 12; - - if (ppc_md.hpte_updatepp(slot, rflags, va, 1, local) == -1) - pte_val(old_pte) &= ~_PAGE_HPTEFLAGS; - } - - if (likely(!(pte_val(old_pte) & _PAGE_HASHPTE))) { - unsigned long hash = hpt_hash(vpn, 1); - unsigned long hpte_group; - - prpn = pte_pfn(old_pte); - -repeat: - hpte_group = ((hash & htab_hash_mask) * - HPTES_PER_GROUP) & ~0x7UL; - - /* Update the linux pte with the HPTE slot */ - pte_val(new_pte) &= ~_PAGE_HPTEFLAGS; - pte_val(new_pte) |= _PAGE_HASHPTE; - - /* Add in WIMG bits */ - /* XXX We should store these in the pte */ - rflags |= _PAGE_COHERENT; - - slot = ppc_md.hpte_insert(hpte_group, va, prpn, - HPTE_V_LARGE, rflags); - - /* Primary is full, try the secondary */ - if (unlikely(slot == -1)) { - pte_val(new_pte) |= _PAGE_SECONDARY; - hpte_group = ((~hash & htab_hash_mask) * - HPTES_PER_GROUP) & ~0x7UL; - slot = ppc_md.hpte_insert(hpte_group, va, prpn, - HPTE_V_LARGE, rflags); - 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"); - - pte_val(new_pte) |= (slot<<12) & _PAGE_GROUP_IX; - - /* - * No need to use ldarx/stdcx here because all who - * might be updating the pte will hold the - * page_table_lock - */ - *ptep = new_pte; - } - - err = 0; - - out: - spin_unlock(&mm->page_table_lock); - - return err; -} |