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Diffstat (limited to 'mm')
-rw-r--r--mm/filemap.c47
-rw-r--r--mm/page-writeback.c20
-rw-r--r--mm/swap.c20
3 files changed, 47 insertions, 40 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index f3d6d89cfd61..6aa6f0cc67e1 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -396,19 +396,17 @@ static int __filemap_fdatawait_range(struct address_space *mapping,
goto out;
pagevec_init(&pvec, 0);
- while ((index <= end) &&
- (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
- PAGECACHE_TAG_WRITEBACK,
- min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1)) != 0) {
+ while (index <= end) {
unsigned i;
+ nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index,
+ end, PAGECACHE_TAG_WRITEBACK);
+ if (!nr_pages)
+ break;
+
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
- /* until radix tree lookup accepts end_index */
- if (page->index > end)
- continue;
-
wait_on_page_writeback(page);
if (TestClearPageError(page))
ret = -EIO;
@@ -1426,9 +1424,10 @@ repeat:
EXPORT_SYMBOL(find_get_pages_contig);
/**
- * find_get_pages_tag - find and return pages that match @tag
+ * find_get_pages_range_tag - find and return pages in given range matching @tag
* @mapping: the address_space to search
* @index: the starting page index
+ * @end: The final page index (inclusive)
* @tag: the tag index
* @nr_pages: the maximum number of pages
* @pages: where the resulting pages are placed
@@ -1436,8 +1435,9 @@ EXPORT_SYMBOL(find_get_pages_contig);
* Like find_get_pages, except we only return pages which are tagged with
* @tag. We update @index to index the next page for the traversal.
*/
-unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index,
- int tag, unsigned int nr_pages, struct page **pages)
+unsigned find_get_pages_range_tag(struct address_space *mapping, pgoff_t *index,
+ pgoff_t end, int tag, unsigned int nr_pages,
+ struct page **pages)
{
struct radix_tree_iter iter;
void **slot;
@@ -1451,6 +1451,9 @@ restart:
radix_tree_for_each_tagged(slot, &mapping->page_tree,
&iter, *index, tag) {
struct page *page;
+
+ if (iter.index > end)
+ break;
repeat:
page = radix_tree_deref_slot(slot);
if (unlikely(!page))
@@ -1489,18 +1492,28 @@ repeat:
}
pages[ret] = page;
- if (++ret == nr_pages)
- break;
+ if (++ret == nr_pages) {
+ *index = pages[ret - 1]->index + 1;
+ goto out;
+ }
}
+ /*
+ * We come here when we got at @end. We take care to not overflow the
+ * index @index as it confuses some of the callers. This breaks the
+ * iteration when there is page at index -1 but that is already broken
+ * anyway.
+ */
+ if (end == (pgoff_t)-1)
+ *index = (pgoff_t)-1;
+ else
+ *index = end + 1;
+out:
rcu_read_unlock();
- if (ret)
- *index = pages[ret - 1]->index + 1;
-
return ret;
}
-EXPORT_SYMBOL(find_get_pages_tag);
+EXPORT_SYMBOL(find_get_pages_range_tag);
/*
* CD/DVDs are error prone. When a medium error occurs, the driver may fail
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index a98dae1bdcff..3ce079e4ed65 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2204,30 +2204,14 @@ retry:
while (!done && (index <= end)) {
int i;
- nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
- min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
+ nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
+ tag);
if (nr_pages == 0)
break;
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
- /*
- * At this point, the page may be truncated or
- * invalidated (changing page->mapping to NULL), or
- * even swizzled back from swapper_space to tmpfs file
- * mapping. However, page->index will not change
- * because we have a reference on the page.
- */
- if (page->index > end) {
- /*
- * can't be range_cyclic (1st pass) because
- * end == -1 in that case.
- */
- done = 1;
- break;
- }
-
done_index = page->index;
lock_page(page);
diff --git a/mm/swap.c b/mm/swap.c
index 39395fb549c0..8e6bcb688779 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -1130,15 +1130,25 @@ unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
}
EXPORT_SYMBOL(pagevec_lookup);
-unsigned pagevec_lookup_tag(struct pagevec *pvec, struct address_space *mapping,
- pgoff_t *index, int tag, unsigned nr_pages)
+unsigned pagevec_lookup_range_tag(struct pagevec *pvec,
+ struct address_space *mapping, pgoff_t *index, pgoff_t end,
+ int tag)
{
- pvec->nr = find_get_pages_tag(mapping, index, tag,
- nr_pages, pvec->pages);
+ pvec->nr = find_get_pages_range_tag(mapping, index, end, tag,
+ PAGEVEC_SIZE, pvec->pages);
return pagevec_count(pvec);
}
-EXPORT_SYMBOL(pagevec_lookup_tag);
+EXPORT_SYMBOL(pagevec_lookup_range_tag);
+unsigned pagevec_lookup_range_nr_tag(struct pagevec *pvec,
+ struct address_space *mapping, pgoff_t *index, pgoff_t end,
+ int tag, unsigned max_pages)
+{
+ pvec->nr = find_get_pages_range_tag(mapping, index, end, tag,
+ min_t(unsigned int, max_pages, PAGEVEC_SIZE), pvec->pages);
+ return pagevec_count(pvec);
+}
+EXPORT_SYMBOL(pagevec_lookup_range_nr_tag);
/*
* Perform any setup for the swap system
*/