From: David S. Miller Date: Mon, 20 Mar 2006 09:17:17 +0000 (-0800) Subject: [SPARC64]: Fix 2 bugs in huge page support. X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=f6b83f070e9b7ad9075f7cc5646260e56c7d0219;p=openwrt%2Fstaging%2Fblogic.git [SPARC64]: Fix 2 bugs in huge page support. 1) huge_pte_offset() did not check the page table hierarchy elements as being empty correctly, resulting in an OOPS 2) Need platform specific hugetlb_get_unmapped_area() to handle the top-down vs. bottom-up address space allocation strategies. Signed-off-by: David S. Miller --- diff --git a/arch/sparc64/mm/hugetlbpage.c b/arch/sparc64/mm/hugetlbpage.c index 625cbb336a23..a7a24869d045 100644 --- a/arch/sparc64/mm/hugetlbpage.c +++ b/arch/sparc64/mm/hugetlbpage.c @@ -1,7 +1,7 @@ /* * SPARC64 Huge TLB page support. * - * Copyright (C) 2002, 2003 David S. Miller (davem@redhat.com) + * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net) */ #include @@ -22,6 +22,175 @@ #include #include +/* 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; @@ -48,12 +217,14 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) pmd_t *pmd; pte_t *pte = NULL; + addr &= HPAGE_MASK; + pgd = pgd_offset(mm, addr); - if (pgd) { + if (!pgd_none(*pgd)) { pud = pud_offset(pgd, addr); - if (pud) { + if (!pud_none(*pud)) { pmd = pmd_offset(pud, addr); - if (pmd) + if (!pmd_none(*pmd)) pte = pte_offset_map(pmd, addr); } } diff --git a/include/asm-sparc64/page.h b/include/asm-sparc64/page.h index f6b49256fe2b..fcb2812265f4 100644 --- a/include/asm-sparc64/page.h +++ b/include/asm-sparc64/page.h @@ -104,6 +104,7 @@ typedef unsigned long pgprot_t; #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) #define ARCH_HAS_SETCLEAR_HUGE_PTE #define ARCH_HAS_HUGETLB_PREFAULT_HOOK +#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA #endif #define TASK_UNMAPPED_BASE (test_thread_flag(TIF_32BIT) ? \