[GFS2] Bug fix to gfs2_readpages()
This fixes a bug where we were releasing a page incorrectly
sometimes when reading a stuffed file. This fixes the bug
that Kevin reported when using Xen.
Cc: Kevin Anderson <kanderso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index 27ce301..2c4ec5c 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -249,8 +249,6 @@
goto out;
}
-#define list_to_page(head) (list_entry((head)->prev, struct page, lru))
-
/**
* gfs2_readpages - Read a bunch of pages at once
*
@@ -290,7 +288,8 @@
struct pagevec lru_pvec;
pagevec_init(&lru_pvec, 0);
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
- struct page *page = list_to_page(pages);
+ struct page *page = list_entry(pages->prev, struct page, lru);
+ prefetchw(&page->flags);
list_del(&page->lru);
if (!add_to_page_cache(page, mapping,
page->index, GFP_KERNEL)) {
@@ -298,8 +297,9 @@
unlock_page(page);
if (!pagevec_add(&lru_pvec, page))
__pagevec_lru_add(&lru_pvec);
+ } else {
+ page_cache_release(page);
}
- page_cache_release(page);
}
pagevec_lru_add(&lru_pvec);
ret = 0;
@@ -321,7 +321,7 @@
out_unlock:
/* unlock all pages, we can't do any I/O right now */
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
- struct page *page = list_to_page(pages);
+ struct page *page = list_entry(pages->prev, struct page, lru);
list_del(&page->lru);
unlock_page(page);
page_cache_release(page);