nilfs2: fix circular locking dependency of writer mutex

[safe/jmp/linux-2.6] / fs / nilfs2 / ioctl.c

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 108d281..be387c6 100644 (file)
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -516,14 +516,16 @@ static ssize_t
 nilfs_ioctl_do_free_segments(struct the_nilfs *nilfs, __u64 *posp, int flags,
                             void *buf, size_t size, size_t nmembs)
 {
-       struct nilfs_sb_info *sbi = nilfs_get_writer(nilfs);
+       struct nilfs_sb_info *sbi = nilfs->ns_writer;
        int ret;
 
-       if (unlikely(!sbi))
+       if (unlikely(!sbi)) {
+               /* never happens because called for a writable mount */
+               WARN_ON(1);
                return -EROFS;
+       }
        ret = nilfs_segctor_add_segments_to_be_freed(
                NILFS_SC(sbi), buf, nmembs);
-       nilfs_put_writer(nilfs);
 
        return (ret < 0) ? ret : nmembs;
 }