BKL-removal: Use unlocked_ioctl for jfs
Convert jfs_ioctl over to not use the BKL. The only potential race
I could see was with two ioctls in parallel changing the flags
and losing the updates. Use the i_mutex to protect against this.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index dfda12a..fc82ecc 100644
--- a/fs/jfs/ioctl.c
+++ b/fs/jfs/ioctl.c
@@ -51,9 +51,9 @@
}
-int jfs_ioctl(struct inode * inode, struct file * filp, unsigned int cmd,
- unsigned long arg)
+long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
+ struct inode *inode = filp->f_dentry->d_inode;
struct jfs_inode_info *jfs_inode = JFS_IP(inode);
unsigned int flags;
@@ -82,6 +82,10 @@
/* Is it quota file? Do not allow user to mess with it */
if (IS_NOQUOTA(inode))
return -EPERM;
+
+ /* Lock against other parallel changes of flags */
+ mutex_lock(&inode->i_mutex);
+
jfs_get_inode_flags(jfs_inode);
oldflags = jfs_inode->mode2;
@@ -92,8 +96,10 @@
if ((oldflags & JFS_IMMUTABLE_FL) ||
((flags ^ oldflags) &
(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
- if (!capable(CAP_LINUX_IMMUTABLE))
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ mutex_unlock(&inode->i_mutex);
return -EPERM;
+ }
}
flags = flags & JFS_FL_USER_MODIFIABLE;
@@ -101,6 +107,7 @@
jfs_inode->mode2 = flags;
jfs_set_inode_flags(inode);
+ mutex_unlock(&inode->i_mutex);
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
return 0;