From 101d2be7646b7dd1c367d50208a59b29fce61398 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 21 Nov 2005 21:32:16 -0800 Subject: [PATCH] [PATCH] unpaged: VM_NONLINEAR VM_RESERVED There's one peculiar use of VM_RESERVED which the previous patch left behind: because VM_NONLINEAR's try_to_unmap_cluster uses vm_private_data as a swapout cursor, but should never meet VM_RESERVED vmas, it was a way of extending VM_NONLINEAR to VM_RESERVED vmas using vm_private_data for some other purpose. But that's an empty set - they don't have the populate function required. So just throw away those VM_RESERVED tests. But one more interesting in rmap.c has to go too: try_to_unmap_one will want to swap out an anonymous page from VM_RESERVED or VM_UNPAGED area. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/fremap.c | 6 ++---- mm/rmap.c | 15 +++++---------- 2 files changed, 7 insertions(+), 14 deletions(-) diff --git a/mm/fremap.c b/mm/fremap.c index 94254c5d7a..007cbad933 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -204,12 +204,10 @@ asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size, * Make sure the vma is shared, that it supports prefaulting, * and that the remapped range is valid and fully within * the single existing vma. vm_private_data is used as a - * swapout cursor in a VM_NONLINEAR vma (unless VM_RESERVED - * or VM_LOCKED, but VM_LOCKED could be revoked later on). + * swapout cursor in a VM_NONLINEAR vma. */ if (vma && (vma->vm_flags & VM_SHARED) && - (!vma->vm_private_data || - (vma->vm_flags & (VM_NONLINEAR|VM_RESERVED))) && + (!vma->vm_private_data || (vma->vm_flags & VM_NONLINEAR)) && vma->vm_ops && vma->vm_ops->populate && end > start && start >= vma->vm_start && end <= vma->vm_end) { diff --git a/mm/rmap.c b/mm/rmap.c index 914d04b98b..377d417ec1 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -529,10 +529,8 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma) * If the page is mlock()d, we cannot swap it out. * If it's recently referenced (perhaps page_referenced * skipped over this mm) then we should reactivate it. - * - * Pages belonging to VM_RESERVED regions should not happen here. */ - if ((vma->vm_flags & (VM_LOCKED|VM_RESERVED)) || + if ((vma->vm_flags & VM_LOCKED) || ptep_clear_flush_young(vma, address, pte)) { ret = SWAP_FAIL; goto out_unmap; @@ -727,7 +725,7 @@ static int try_to_unmap_file(struct page *page) list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { - if (vma->vm_flags & (VM_LOCKED|VM_RESERVED)) + if (vma->vm_flags & VM_LOCKED) continue; cursor = (unsigned long) vma->vm_private_data; if (cursor > max_nl_cursor) @@ -761,7 +759,7 @@ static int try_to_unmap_file(struct page *page) do { list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { - if (vma->vm_flags & (VM_LOCKED|VM_RESERVED)) + if (vma->vm_flags & VM_LOCKED) continue; cursor = (unsigned long) vma->vm_private_data; while ( cursor < max_nl_cursor && @@ -783,11 +781,8 @@ static int try_to_unmap_file(struct page *page) * in locked vmas). Reset cursor on all unreserved nonlinear * vmas, now forgetting on which ones it had fallen behind. */ - list_for_each_entry(vma, &mapping->i_mmap_nonlinear, - shared.vm_set.list) { - if (!(vma->vm_flags & VM_RESERVED)) - vma->vm_private_data = NULL; - } + list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) + vma->vm_private_data = NULL; out: spin_unlock(&mapping->i_mmap_lock); return ret; -- 2.39.5