From: Suparna Bhattacharya <suparna@in.ibm.com>
The AIO patches have a tricky problem with unlock_page(), described in the
next patch.
To fix it we need to change the page gang-lookup API so that it can return to
the caller the page index at which the next search should commence.
This patch make that change, and updates callers.
---
25-akpm/fs/hugetlbfs/inode.c | 5 +----
25-akpm/include/linux/pagemap.h | 2 +-
25-akpm/include/linux/pagevec.h | 2 +-
25-akpm/mm/filemap.c | 12 +++++++++---
25-akpm/mm/swap.c | 9 ++++++---
25-akpm/mm/truncate.c | 20 ++++----------------
6 files changed, 22 insertions(+), 28 deletions(-)
diff -puN fs/hugetlbfs/inode.c~gang_lookup_next fs/hugetlbfs/inode.c
--- 25/fs/hugetlbfs/inode.c~gang_lookup_next Thu Jan 8 15:26:42 2004
+++ 25-akpm/fs/hugetlbfs/inode.c Thu Jan 8 15:26:42 2004
@@ -165,7 +165,7 @@ void truncate_hugepages(struct address_s
pagevec_init(&pvec, 0);
next = start;
while (1) {
- if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
+ if (!pagevec_lookup(&pvec, mapping, &next, PAGEVEC_SIZE)) {
if (next == start)
break;
next = start;
@@ -176,9 +176,6 @@ void truncate_hugepages(struct address_s
struct page *page = pvec.pages[i];
lock_page(page);
- if (page->index > next)
- next = page->index;
- ++next;
truncate_huge_page(page);
unlock_page(page);
hugetlb_put_quota(mapping);
diff -puN include/linux/pagemap.h~gang_lookup_next include/linux/pagemap.h
--- 25/include/linux/pagemap.h~gang_lookup_next Thu Jan 8 15:26:42 2004
+++ 25-akpm/include/linux/pagemap.h Thu Jan 8 15:26:42 2004
@@ -70,7 +70,7 @@ extern struct page * find_trylock_page(s
extern struct page * find_or_create_page(struct address_space *mapping,
unsigned long index, unsigned int gfp_mask);
extern unsigned int find_get_pages(struct address_space *mapping,
- pgoff_t start, unsigned int nr_pages,
+ pgoff_t *next, unsigned int nr_pages,
struct page **pages);
/*
diff -puN include/linux/pagevec.h~gang_lookup_next include/linux/pagevec.h
--- 25/include/linux/pagevec.h~gang_lookup_next Thu Jan 8 15:26:42 2004
+++ 25-akpm/include/linux/pagevec.h Thu Jan 8 15:26:42 2004
@@ -23,7 +23,7 @@ void __pagevec_lru_add(struct pagevec *p
void __pagevec_lru_add_active(struct pagevec *pvec);
void pagevec_strip(struct pagevec *pvec);
unsigned int pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
- pgoff_t start, unsigned int nr_pages);
+ pgoff_t *next, unsigned int nr_pages);
static inline void pagevec_init(struct pagevec *pvec, int cold)
{
diff -puN mm/filemap.c~gang_lookup_next mm/filemap.c
--- 25/mm/filemap.c~gang_lookup_next Thu Jan 8 15:26:42 2004
+++ 25-akpm/mm/filemap.c Thu Jan 8 15:26:42 2004
@@ -592,9 +592,12 @@ EXPORT_SYMBOL(find_or_create_page);
* The search returns a group of mapping-contiguous pages with ascending
* indexes. There may be holes in the indices due to not-present pages.
*
- * find_get_pages() returns the number of pages which were found.
+ * find_get_pages() returns the number of pages which were found
+ * and also atomically sets the next offset to continue looking up
+ * mapping contiguous pages from (useful when doing a range of
+ * pagevec lookups in chunks of PAGEVEC_SIZE).
*/
-unsigned int find_get_pages(struct address_space *mapping, pgoff_t start,
+unsigned int find_get_pages(struct address_space *mapping, pgoff_t *next,
unsigned int nr_pages, struct page **pages)
{
unsigned int i;
@@ -602,9 +605,12 @@ unsigned int find_get_pages(struct addre
spin_lock(&mapping->page_lock);
ret = radix_tree_gang_lookup(&mapping->page_tree,
- (void **)pages, start, nr_pages);
+ (void **)pages, *next, nr_pages);
for (i = 0; i < ret; i++)
page_cache_get(pages[i]);
+ if (ret)
+ *next = pages[ret - 1]->index + 1;
+
spin_unlock(&mapping->page_lock);
return ret;
}
diff -puN mm/swap.c~gang_lookup_next mm/swap.c
--- 25/mm/swap.c~gang_lookup_next Thu Jan 8 15:26:42 2004
+++ 25-akpm/mm/swap.c Thu Jan 8 15:26:42 2004
@@ -348,12 +348,15 @@ void pagevec_strip(struct pagevec *pvec)
* The search returns a group of mapping-contiguous pages with ascending
* indexes. There may be holes in the indices due to not-present pages.
*
- * pagevec_lookup() returns the number of pages which were found.
+ * pagevec_lookup() returns the number of pages which were found
+ * and also atomically sets the next offset to continue looking up
+ * mapping contiguous pages from (useful when doing a range of
+ * pagevec lookups in chunks of PAGEVEC_SIZE).
*/
unsigned int pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
- pgoff_t start, unsigned int nr_pages)
+ pgoff_t *next, unsigned int nr_pages)
{
- pvec->nr = find_get_pages(mapping, start, nr_pages, pvec->pages);
+ pvec->nr = find_get_pages(mapping, next, nr_pages, pvec->pages);
return pagevec_count(pvec);
}
diff -puN mm/truncate.c~gang_lookup_next mm/truncate.c
--- 25/mm/truncate.c~gang_lookup_next Thu Jan 8 15:26:42 2004
+++ 25-akpm/mm/truncate.c Thu Jan 8 15:26:42 2004
@@ -122,14 +122,10 @@ void truncate_inode_pages(struct address
pagevec_init(&pvec, 0);
next = start;
- while (pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
+ while (pagevec_lookup(&pvec, mapping, &next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
- pgoff_t page_index = page->index;
- if (page_index > next)
- next = page_index;
- next++;
if (TestSetPageLocked(page))
continue;
if (PageWriteback(page)) {
@@ -155,7 +151,7 @@ void truncate_inode_pages(struct address
next = start;
for ( ; ; ) {
- if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
+ if (!pagevec_lookup(&pvec, mapping, &next, PAGEVEC_SIZE)) {
if (next == start)
break;
next = start;
@@ -166,9 +162,6 @@ void truncate_inode_pages(struct address
lock_page(page);
wait_on_page_writeback(page);
- if (page->index > next)
- next = page->index;
- next++;
truncate_complete_page(mapping, page);
unlock_page(page);
}
@@ -209,17 +202,13 @@ unsigned long invalidate_mapping_pages(s
pagevec_init(&pvec, 0);
while (next <= end &&
- pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
+ pagevec_lookup(&pvec, mapping, &next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
if (TestSetPageLocked(page)) {
- next++;
continue;
}
- if (page->index > next)
- next = page->index;
- next++;
if (PageDirty(page) || PageWriteback(page))
goto unlock;
if (page_mapped(page))
@@ -258,14 +247,13 @@ void invalidate_inode_pages2(struct addr
int i;
pagevec_init(&pvec, 0);
- while (pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
+ while (pagevec_lookup(&pvec, mapping, &next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
lock_page(page);
if (page->mapping == mapping) { /* truncate race? */
wait_on_page_writeback(page);
- next = page->index + 1;
if (page_mapped(page))
clear_page_dirty(page);
else
_