diff options
Diffstat (limited to 'fs/proc/task_mmu.c')
-rw-r--r-- | fs/proc/task_mmu.c | 67 |
1 files changed, 45 insertions, 22 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 0482e7cb1fb7..932a822d9420 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1055,9 +1055,8 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct vm_area_struct *vma; struct pagemapread *pm = walk->private; spinlock_t *ptl; - pte_t *pte; + pte_t *pte, *orig_pte; int err = 0; - pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2)); /* find the first VMA at or above 'addr' */ vma = find_vma(walk->mm, addr); @@ -1071,6 +1070,7 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, for (; addr != end; addr += PAGE_SIZE) { unsigned long offset; + pagemap_entry_t pme; offset = (addr & ~PAGEMAP_WALK_MASK) >> PAGE_SHIFT; @@ -1085,32 +1085,55 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, if (pmd_trans_unstable(pmd)) return 0; - for (; addr != end; addr += PAGE_SIZE) { - int flags2; - - /* check to see if we've left 'vma' behind - * and need a new, higher one */ - if (vma && (addr >= vma->vm_end)) { - vma = find_vma(walk->mm, addr); - if (vma && (vma->vm_flags & VM_SOFTDIRTY)) - flags2 = __PM_SOFT_DIRTY; - else - flags2 = 0; - pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2)); + + while (1) { + /* End of address space hole, which we mark as non-present. */ + unsigned long hole_end; + + if (vma) + hole_end = min(end, vma->vm_start); + else + hole_end = end; + + for (; addr < hole_end; addr += PAGE_SIZE) { + pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2)); + + err = add_to_pagemap(addr, &pme, pm); + if (err) + return err; } - /* check that 'vma' actually covers this address, - * and that it isn't a huge page vma */ - if (vma && (vma->vm_start <= addr) && - !is_vm_hugetlb_page(vma)) { - pte = pte_offset_map(pmd, addr); + if (!vma || vma->vm_start >= end) + break; + /* + * We can't possibly be in a hugetlb VMA. In general, + * for a mm_walk with a pmd_entry and a hugetlb_entry, + * the pmd_entry can only be called on addresses in a + * hugetlb if the walk starts in a non-hugetlb VMA and + * spans a hugepage VMA. Since pagemap_read walks are + * PMD-sized and PMD-aligned, this will never be true. + */ + BUG_ON(is_vm_hugetlb_page(vma)); + + /* Addresses in the VMA. */ + orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + for (; addr < min(end, vma->vm_end); pte++, addr += PAGE_SIZE) { + pagemap_entry_t pme; + pte_to_pagemap_entry(&pme, pm, vma, addr, *pte); - /* unmap before userspace copy */ - pte_unmap(pte); + err = add_to_pagemap(addr, &pme, pm); + if (err) + break; } - err = add_to_pagemap(addr, &pme, pm); + pte_unmap_unlock(orig_pte, ptl); + if (err) return err; + + if (addr == end) + break; + + vma = find_vma(walk->mm, addr); } cond_resched(); |