Btrfs: do not warn_on io_ctl->cur in io_ctl_map_page

io_ctl_map_page is called by many functions in free-space-cache.
In most scenarios, the ->cur is not null, e.g. io_ctl_add_entry.
I think we'd better remove the warn_on here.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 557502c..efdd1d3 100644 (file)
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -307,7 +307,6 @@ static void io_ctl_unmap_page(struct io_ctl *io_ctl)
 
 static void io_ctl_map_page(struct io_ctl *io_ctl, int clear)
 {
-       WARN_ON(io_ctl->cur);
        BUG_ON(io_ctl->index >= io_ctl->num_pages);
        io_ctl->page = io_ctl->pages[io_ctl->index++];
        io_ctl->cur = kmap(io_ctl->page);