mm: add unmap_mapping_pages()
Several users of unmap_mapping_range() would prefer to express their
range in pages rather than bytes. Unfortuately, on a 32-bit kernel, you
have to remember to cast your page number to a 64-bit type before
shifting it, and four places in the current tree didn't remember to do
that. That's a sign of a bad interface.
Conveniently, unmap_mapping_range() actually converts from bytes into
pages, so hoist the guts of unmap_mapping_range() into a new function
unmap_mapping_pages() and convert the callers which want to use pages.
Link: http://lkml.kernel.org/r/20171206142627.GD32044@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: "zhangyi (F)" <yi.zhang@huawei.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/truncate.c b/mm/truncate.c
index e4b4cf0..c34e2fd 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -179,12 +179,8 @@
truncate_cleanup_page(struct address_space *mapping, struct page *page)
{
if (page_mapped(page)) {
- loff_t holelen;
-
- holelen = PageTransHuge(page) ? HPAGE_PMD_SIZE : PAGE_SIZE;
- unmap_mapping_range(mapping,
- (loff_t)page->index << PAGE_SHIFT,
- holelen, 0);
+ pgoff_t nr = PageTransHuge(page) ? HPAGE_PMD_NR : 1;
+ unmap_mapping_pages(mapping, page->index, nr, false);
}
if (page_has_private(page))
@@ -715,19 +711,15 @@
/*
* Zap the rest of the file in one hit.
*/
- unmap_mapping_range(mapping,
- (loff_t)index << PAGE_SHIFT,
- (loff_t)(1 + end - index)
- << PAGE_SHIFT,
- 0);
+ unmap_mapping_pages(mapping, index,
+ (1 + end - index), false);
did_range_unmap = 1;
} else {
/*
* Just zap this page
*/
- unmap_mapping_range(mapping,
- (loff_t)index << PAGE_SHIFT,
- PAGE_SIZE, 0);
+ unmap_mapping_pages(mapping, index,
+ 1, false);
}
}
BUG_ON(page_mapped(page));
@@ -753,8 +745,7 @@
* get remapped later.
*/
if (dax_mapping(mapping)) {
- unmap_mapping_range(mapping, (loff_t)start << PAGE_SHIFT,
- (loff_t)(end - start + 1) << PAGE_SHIFT, 0);
+ unmap_mapping_pages(mapping, start, end - start + 1, false);
}
out:
cleancache_invalidate_inode(mapping);