Filipe Manana 於 2020/7/17 下午8:00 寫道:
On Fri, Jul 17, 2020 at 11:23 AM robbieko <robbieko@xxxxxxxxxxxx> wrote:
From: Robbie Ko <robbieko@xxxxxxxxxxxx>
When lock_delalloc_page, we first lock the page and then
check that the page dirty, if the page is not dirty, we
will return -EAGAIN but all pages must be freed, otherwise
page leak.
"When lock_delalloc_page" -> When locking pages for delalloc
We check if it's dirty and if the mapping still matches.
Btw, you can make line length closer to 75 characters, it makes things
a bit more readable.
The subject is also a bit confusing:
"btrfs: fix memory leak for page count"
something along the lines "btrfs: fix page leaks after failure to lock
page for delalloc" would be more clear to me at least,
it gives a clue about where the problem is.
OK, I will resend patch.
Thanks.
Signed-off-by: Robbie Ko <robbieko@xxxxxxxxxxxx>
The code looks correct, thanks.
Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx>
---
fs/btrfs/extent_io.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 68c96057ad2d..34d55b1e2a88 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1951,7 +1951,7 @@ static int __process_pages_contig(struct address_space *mapping,
struct page *pages[16];
unsigned ret;
int err = 0;
- int i;
+ int i, j;
if (page_ops & PAGE_LOCK) {
ASSERT(page_ops == PAGE_LOCK);
@@ -1999,7 +1999,8 @@ static int __process_pages_contig(struct address_space *mapping,
if (!PageDirty(pages[i]) ||
pages[i]->mapping != mapping) {
unlock_page(pages[i]);
- put_page(pages[i]);
+ for (j = i; j < ret; j++)
+ put_page(pages[j]);
err = -EAGAIN;
goto out;
}
--
2.17.1
