| /* |
| * SPARC64 Huge TLB page support. |
| * |
| * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net) |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/module.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/sysctl.h> |
| |
| #include <asm/mman.h> |
| #include <asm/pgalloc.h> |
| #include <asm/tlb.h> |
| #include <asm/tlbflush.h> |
| #include <asm/cacheflush.h> |
| #include <asm/mmu_context.h> |
| |
| /* Slightly simplified from the non-hugepage variant because by |
| * definition we don't have to worry about any page coloring stuff |
| */ |
| #define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL)) |
| #define VA_EXCLUDE_END (0xfffff80000000000UL + (1UL << 32UL)) |
| |
| static unsigned long hugetlb_get_unmapped_area_bottomup(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 task_size = TASK_SIZE; |
| unsigned long start_addr; |
| |
| if (test_thread_flag(TIF_32BIT)) |
| task_size = STACK_TOP32; |
| if (unlikely(len >= VA_EXCLUDE_START)) |
| return -ENOMEM; |
| |
| 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; |
| } |
| |
| task_size -= len; |
| |
| full_search: |
| addr = ALIGN(addr, HPAGE_SIZE); |
| |
| for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { |
| /* At this point: (!vma || addr < vma->vm_end). */ |
| if (addr < VA_EXCLUDE_START && |
| (addr + len) >= VA_EXCLUDE_START) { |
| addr = VA_EXCLUDE_END; |
| vma = find_vma(mm, VA_EXCLUDE_END); |
| } |
| if (unlikely(task_size < addr)) { |
| if (start_addr != TASK_UNMAPPED_BASE) { |
| start_addr = addr = TASK_UNMAPPED_BASE; |
| mm->cached_hole_size = 0; |
| goto full_search; |
| } |
| return -ENOMEM; |
| } |
| if (likely(!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 = ALIGN(vma->vm_end, HPAGE_SIZE); |
| } |
| } |
| |
| static unsigned long |
| hugetlb_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; |
| struct mm_struct *mm = current->mm; |
| unsigned long addr = addr0; |
| |
| /* This should only ever run for 32-bit processes. */ |
| BUG_ON(!test_thread_flag(TIF_32BIT)); |
| |
| /* check if free_area_cache is useful for us */ |
| if (len <= mm->cached_hole_size) { |
| mm->cached_hole_size = 0; |
| mm->free_area_cache = mm->mmap_base; |
| } |
| |
| /* either no address requested or can't fit in requested address hole */ |
| addr = mm->free_area_cache & HPAGE_MASK; |
| |
| /* make sure it can fit in the remaining address space */ |
| if (likely(addr > len)) { |
| vma = find_vma(mm, addr-len); |
| if (!vma || addr <= vma->vm_start) { |
| /* remember the address as a hint for next time */ |
| return (mm->free_area_cache = addr-len); |
| } |
| } |
| |
| if (unlikely(mm->mmap_base < len)) |
| goto bottomup; |
| |
| addr = (mm->mmap_base-len) & HPAGE_MASK; |
| |
| do { |
| /* |
| * Lookup failure means no vma is above this address, |
| * else if new region fits below vma->vm_start, |
| * return with success: |
| */ |
| vma = find_vma(mm, addr); |
| if (likely(!vma || addr+len <= vma->vm_start)) { |
| /* remember the address as a hint for next time */ |
| return (mm->free_area_cache = addr); |
| } |
| |
| /* remember the largest hole we saw so far */ |
| if (addr + mm->cached_hole_size < vma->vm_start) |
| mm->cached_hole_size = vma->vm_start - addr; |
| |
| /* try just below the current vma->vm_start */ |
| addr = (vma->vm_start-len) & HPAGE_MASK; |
| } while (likely(len < vma->vm_start)); |
| |
| bottomup: |
| /* |
| * 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->cached_hole_size = ~0UL; |
| mm->free_area_cache = TASK_UNMAPPED_BASE; |
| addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags); |
| /* |
| * Restore the topdown base: |
| */ |
| mm->free_area_cache = mm->mmap_base; |
| mm->cached_hole_size = ~0UL; |
| |
| return addr; |
| } |
| |
| unsigned long |
| hugetlb_get_unmapped_area(struct file *file, 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 task_size = TASK_SIZE; |
| |
| if (test_thread_flag(TIF_32BIT)) |
| task_size = STACK_TOP32; |
| |
| if (len & ~HPAGE_MASK) |
| return -EINVAL; |
| if (len > task_size) |
| return -ENOMEM; |
| |
| if (addr) { |
| addr = ALIGN(addr, HPAGE_SIZE); |
| vma = find_vma(mm, addr); |
| if (task_size - len >= addr && |
| (!vma || addr + len <= vma->vm_start)) |
| return addr; |
| } |
| if (mm->get_unmapped_area == arch_get_unmapped_area) |
| return hugetlb_get_unmapped_area_bottomup(file, addr, len, |
| pgoff, flags); |
| else |
| return hugetlb_get_unmapped_area_topdown(file, addr, len, |
| pgoff, flags); |
| } |
| |
| pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr) |
| { |
| pgd_t *pgd; |
| pud_t *pud; |
| pmd_t *pmd; |
| pte_t *pte = NULL; |
| |
| /* We must align the address, because our caller will run |
| * set_huge_pte_at() on whatever we return, which writes out |
| * all of the sub-ptes for the hugepage range. So we have |
| * to give it the first such sub-pte. |
| */ |
| addr &= HPAGE_MASK; |
| |
| pgd = pgd_offset(mm, addr); |
| pud = pud_alloc(mm, pgd, addr); |
| if (pud) { |
| pmd = pmd_alloc(mm, pud, addr); |
| if (pmd) |
| pte = pte_alloc_map(mm, pmd, addr); |
| } |
| return pte; |
| } |
| |
| pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) |
| { |
| pgd_t *pgd; |
| pud_t *pud; |
| pmd_t *pmd; |
| pte_t *pte = NULL; |
| |
| addr &= HPAGE_MASK; |
| |
| pgd = pgd_offset(mm, addr); |
| if (!pgd_none(*pgd)) { |
| pud = pud_offset(pgd, addr); |
| if (!pud_none(*pud)) { |
| pmd = pmd_offset(pud, addr); |
| if (!pmd_none(*pmd)) |
| pte = pte_offset_map(pmd, addr); |
| } |
| } |
| return pte; |
| } |
| |
| void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, |
| pte_t *ptep, pte_t entry) |
| { |
| int i; |
| |
| if (!pte_present(*ptep) && pte_present(entry)) |
| mm->context.huge_pte_count++; |
| |
| for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) { |
| set_pte_at(mm, addr, ptep, entry); |
| ptep++; |
| addr += PAGE_SIZE; |
| pte_val(entry) += PAGE_SIZE; |
| } |
| } |
| |
| pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, |
| pte_t *ptep) |
| { |
| pte_t entry; |
| int i; |
| |
| entry = *ptep; |
| if (pte_present(entry)) |
| mm->context.huge_pte_count--; |
| |
| for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) { |
| pte_clear(mm, addr, ptep); |
| addr += PAGE_SIZE; |
| ptep++; |
| } |
| |
| return entry; |
| } |
| |
| struct page *follow_huge_addr(struct mm_struct *mm, |
| unsigned long address, int write) |
| { |
| return ERR_PTR(-EINVAL); |
| } |
| |
| 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) |
| { |
| return NULL; |
| } |
| |
| static void context_reload(void *__data) |
| { |
| struct mm_struct *mm = __data; |
| |
| if (mm == current->mm) |
| load_secondary_context(mm); |
| } |
| |
| void hugetlb_prefault_arch_hook(struct mm_struct *mm) |
| { |
| struct tsb_config *tp = &mm->context.tsb_block[MM_TSB_HUGE]; |
| |
| if (likely(tp->tsb != NULL)) |
| return; |
| |
| tsb_grow(mm, MM_TSB_HUGE, 0); |
| tsb_context_switch(mm); |
| smp_tsb_sync(mm); |
| |
| /* On UltraSPARC-III+ and later, configure the second half of |
| * the Data-TLB for huge pages. |
| */ |
| if (tlb_type == cheetah_plus) { |
| unsigned long ctx; |
| |
| spin_lock(&ctx_alloc_lock); |
| ctx = mm->context.sparc64_ctx_val; |
| ctx &= ~CTX_PGSZ_MASK; |
| ctx |= CTX_PGSZ_BASE << CTX_PGSZ0_SHIFT; |
| ctx |= CTX_PGSZ_HUGE << CTX_PGSZ1_SHIFT; |
| |
| if (ctx != mm->context.sparc64_ctx_val) { |
| /* When changing the page size fields, we |
| * must perform a context flush so that no |
| * stale entries match. This flush must |
| * occur with the original context register |
| * settings. |
| */ |
| do_flush_tlb_mm(mm); |
| |
| /* Reload the context register of all processors |
| * also executing in this address space. |
| */ |
| mm->context.sparc64_ctx_val = ctx; |
| on_each_cpu(context_reload, mm, 0, 0); |
| } |
| spin_unlock(&ctx_alloc_lock); |
| } |
| } |