In iomap_write_end, we're not holding a page reference anymore when
calling the page_done callback, but the callback needs that reference to
access the page. To fix that, move the put_page call in
__generic_write_end into the callers of __generic_write_end. Then, in
iomap_write_end, put the page after calling the page_done callback.
Reported-by: Jan Kara <jack@xxxxxxx>
Fixes: 63899c6f8851 ("iomap: add a page_done callback")
Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
---
fs/buffer.c | 5 +++--
fs/iomap.c | 1 +
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/buffer.c b/fs/buffer.c
index ce357602f471..6e2c95160ce3 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2104,7 +2104,6 @@ int __generic_write_end(struct inode *inode, loff_t pos, unsigned copied,
}
unlock_page(page);
- put_page(page);
if (old_size < pos)
pagecache_isize_extended(inode, old_size, pos);
@@ -2160,7 +2159,9 @@ int generic_write_end(struct file *file, struct address_space *mapping,
struct page *page, void *fsdata)
{
copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
- return __generic_write_end(mapping->host, pos, copied, page);
+ copied = __generic_write_end(mapping->host, pos, copied, page);
+ put_page(page);
+ return copied;
}
EXPORT_SYMBOL(generic_write_end);
diff --git a/fs/iomap.c b/fs/iomap.c
index 2344c662e6fc..b01ed5a28d2c 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -780,6 +780,7 @@ iomap_write_end(struct inode *inode, loff_t pos, unsigned len,
ret = __generic_write_end(inode, pos, ret, page);
if (iomap->page_done)
iomap->page_done(inode, pos, copied, page, iomap);
+ put_page(page);
if (ret < len)
iomap_write_failed(inode, pos, len);
--
2.20.1
