diff options
| -rw-r--r-- | mm/mlock.c | 81 |
1 files changed, 64 insertions, 17 deletions
diff --git a/mm/mlock.c b/mm/mlock.c index 4f318642fbb..67b3dd8616d 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -377,18 +377,10 @@ static int mlock_fixup(struct vm_area_struct *vma, struct vm_area_struct **prev, int ret = 0; int lock = newflags & VM_LOCKED; - if (newflags == vma->vm_flags || - (vma->vm_flags & (VM_IO | VM_PFNMAP))) + if (newflags == vma->vm_flags || (vma->vm_flags & VM_SPECIAL) || + is_vm_hugetlb_page(vma) || vma == get_gate_vma(current)) goto out; /* don't set VM_LOCKED, don't count */ - if ((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) || - is_vm_hugetlb_page(vma) || - vma == get_gate_vma(current)) { - if (lock) - make_pages_present(start, end); - goto out; /* don't set VM_LOCKED, don't count */ - } - pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); *prev = vma_merge(mm, *prev, start, end, newflags, vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma)); @@ -424,14 +416,10 @@ success: * set VM_LOCKED, __mlock_vma_pages_range will bring it back. */ - if (lock) { + if (lock) vma->vm_flags = newflags; - ret = __mlock_vma_pages_range(vma, start, end); - if (ret < 0) - ret = __mlock_posix_error_return(ret); - } else { + else munlock_vma_pages_range(vma, start, end); - } out: *prev = vma; @@ -444,7 +432,8 @@ static int do_mlock(unsigned long start, size_t len, int on) struct vm_area_struct * vma, * prev; int error; - len = PAGE_ALIGN(len); + VM_BUG_ON(start & ~PAGE_MASK); + VM_BUG_ON(len != PAGE_ALIGN(len)); end = start + len; if (end < start) return -EINVAL; @@ -487,6 +476,58 @@ static int do_mlock(unsigned long start, size_t len, int on) return error; } +static int do_mlock_pages(unsigned long start, size_t len, int ignore_errors) +{ + struct mm_struct *mm = current->mm; + unsigned long end, nstart, nend; + struct vm_area_struct *vma = NULL; + int ret = 0; + + VM_BUG_ON(start & ~PAGE_MASK); + VM_BUG_ON(len != PAGE_ALIGN(len)); + end = start + len; + + down_read(&mm->mmap_sem); + for (nstart = start; nstart < end; nstart = nend) { + /* + * We want to fault in pages for [nstart; end) address range. + * Find first corresponding VMA. + */ + if (!vma) + vma = find_vma(mm, nstart); + else + vma = vma->vm_next; + if (!vma || vma->vm_start >= end) + break; + /* + * Set [nstart; nend) to intersection of desired address + * range with the first VMA. Also, skip undesirable VMA types. + */ + nend = min(end, vma->vm_end); + if (vma->vm_flags & (VM_IO | VM_PFNMAP)) + continue; + if (nstart < vma->vm_start) + nstart = vma->vm_start; + /* + * Now fault in a range of pages within the first VMA. + */ + if (vma->vm_flags & VM_LOCKED) { + ret = __mlock_vma_pages_range(vma, nstart, nend); + if (ret < 0 && ignore_errors) { + ret = 0; + continue; /* continue at next VMA */ + } + if (ret) { + ret = __mlock_posix_error_return(ret); + break; + } + } else + make_pages_present(nstart, nend); + } + up_read(&mm->mmap_sem); + return ret; /* 0 or negative error code */ +} + SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) { unsigned long locked; @@ -512,6 +553,8 @@ SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) if ((locked <= lock_limit) || capable(CAP_IPC_LOCK)) error = do_mlock(start, len, 1); up_write(¤t->mm->mmap_sem); + if (!error) + error = do_mlock_pages(start, len, 0); return error; } @@ -576,6 +619,10 @@ SYSCALL_DEFINE1(mlockall, int, flags) capable(CAP_IPC_LOCK)) ret = do_mlockall(flags); up_write(¤t->mm->mmap_sem); + if (!ret && (flags & MCL_CURRENT)) { + /* Ignore errors */ + do_mlock_pages(0, TASK_SIZE, 1); + } out: return ret; } |