From 25122d15e21cf252e91e4cad7cea760f97df29f1 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <idryomov@gmail.com>
Date: Sun, 20 Jan 2013 15:57:57 +0200
Subject: [PATCH] Btrfs: reorder locks and sanity checks in btrfs_ioctl_defrag
Operation-specific check (whether subvol is readonly or not) should go
after the mutual exclusiveness check.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
fs/btrfs/ioctl.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f5c1c150d9f3..afbf3ac2079d 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2186,19 +2186,20 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
struct btrfs_ioctl_defrag_range_args *range;
int ret;
- if (btrfs_root_readonly(root))
- return -EROFS;
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1)) {
pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
+ mnt_drop_write_file(file);
return -EINVAL;
}
- ret = mnt_want_write_file(file);
- if (ret) {
- atomic_set(&root->fs_info->mutually_exclusive_operation_running,
- 0);
- return ret;
+
+ if (btrfs_root_readonly(root)) {
+ ret = -EROFS;
+ goto out;
}
switch (inode->i_mode & S_IFMT) {
@@ -2250,8 +2251,8 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
ret = -EINVAL;
}
out:
- mnt_drop_write_file(file);
atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
+ mnt_drop_write_file(file);
return ret;
}
--
2.34.1