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| author | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-28 23:34:23 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-28 23:34:23 +0100 |
| commit | 6aab341e0a28aff100a09831c5300a2994b8b986 (patch) | |
| tree | 1af3908275aa5e1b16e80efee554a9a7504c56d4 /mm/msync.c | |
| parent | [PATCH] drivers/scsi/dpt_i2o.c: fix a NULL pointer dereference (diff) | |
| download | linux-6aab341e0a28aff100a09831c5300a2994b8b986.tar.xz linux-6aab341e0a28aff100a09831c5300a2994b8b986.zip | |
mm: re-architect the VM_UNPAGED logic
This replaces the (in my opinion horrible) VM_UNMAPPED logic with very
explicit support for a "remapped page range" aka VM_PFNMAP. It allows a
VM area to contain an arbitrary range of page table entries that the VM
never touches, and never considers to be normal pages.
Any user of "remap_pfn_range()" automatically gets this new
functionality, and doesn't even have to mark the pages reserved or
indeed mark them any other way. It just works. As a side effect, doing
mmap() on /dev/mem works for arbitrary ranges.
Sparc update from David in the next commit.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm/msync.c')
| -rw-r--r-- | mm/msync.c | 12 |
1 files changed, 3 insertions, 9 deletions
diff --git a/mm/msync.c b/mm/msync.c index b3f4caf3010b..1b5b6f662dcf 100644 --- a/mm/msync.c +++ b/mm/msync.c @@ -27,7 +27,6 @@ static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd, again: pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); do { - unsigned long pfn; struct page *page; if (progress >= 64) { @@ -40,13 +39,9 @@ again: continue; if (!pte_maybe_dirty(*pte)) continue; - pfn = pte_pfn(*pte); - if (unlikely(!pfn_valid(pfn))) { - print_bad_pte(vma, *pte, addr); + page = vm_normal_page(vma, addr, *pte); + if (!page) continue; - } - page = pfn_to_page(pfn); - if (ptep_clear_flush_dirty(vma, addr, pte) || page_test_and_clear_dirty(page)) set_page_dirty(page); @@ -97,9 +92,8 @@ static void msync_page_range(struct vm_area_struct *vma, /* For hugepages we can't go walking the page table normally, * but that's ok, hugetlbfs is memory based, so we don't need * to do anything more on an msync(). - * Can't do anything with VM_UNPAGED regions either. */ - if (vma->vm_flags & (VM_HUGETLB|VM_UNPAGED)) + if (vma->vm_flags & VM_HUGETLB) return; BUG_ON(addr >= end); |