BKL: Remove BKL from ecryptfs

The BKL is only used in fill_super, which is protected by the superblocks
s_umount rw_semaphorei, and in fasync, which does not do anything that
could require the BKL. Therefore it is safe to remove the BKL entirely.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Dustin Kirkland <kirkland@canonical.com>
Cc: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Cc: ecryptfs-devel@lists.launchpad.net

fs/ecryptfs/file.c

@@ -31,7 +31,6 @@
 #include <linux/security.h>
 #include <linux/compat.h>
 #include <linux/fs_stack.h>
-#include <linux/smp_lock.h>
 #include "ecryptfs_kernel.h"
 
 /**
@@ -284,11 +283,9 @@ static int ecryptfs_fasync(int fd, struct file *file, int flag)
 	int rc = 0;
 	struct file *lower_file = NULL;
 
-	lock_kernel();
 	lower_file = ecryptfs_file_to_lower(file);
 	if (lower_file->f_op && lower_file->f_op->fasync)
 		rc = lower_file->f_op->fasync(fd, lower_file, flag);
-	unlock_kernel();
 	return rc;
 }
 

fs/ecryptfs/main.c

@@ -36,7 +36,6 @@
 #include <linux/parser.h>
 #include <linux/fs_stack.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>     /* For lock_kernel() */
 #include "ecryptfs_kernel.h"
 
 /**
@@ -551,7 +550,6 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags,
 	const char *err = "Getting sb failed";
 	int rc;
 
-	lock_kernel();
 	sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL);
 	if (!sbi) {
 		rc = -ENOMEM;
@@ -610,7 +608,6 @@ static int ecryptfs_get_sb(struct file_system_type *fs_type, int flags,
 		goto out;
 	}
 	simple_set_mnt(mnt, s);
-	unlock_kernel();
 	return 0;
 
 out:
@@ -619,7 +616,6 @@ out:
 		kmem_cache_free(ecryptfs_sb_info_cache, sbi);
 	}
 	printk(KERN_ERR "%s; rc = [%d]\n", err, rc);
-	unlock_kernel();
 	return rc;
 }