From: Jan Blunck Subject: [PATCH 7/7] BKL: Remove BKL from ext2 filesystem Date: Wed, 14 Apr 2010 14:38:39 +0200 Message-ID: <1271248719-21488-8-git-send-email-jblunck@suse.de> References: <1271248719-21488-1-git-send-email-jblunck@suse.de> Cc: Linux-Kernel Mailinglist , linux-ext4@vger.kernel.org, Frederic Weisbecker , Arnd Bergmann , Jan Blunck , Jan Kara To: Jan Kara , tytso@mit.edu Return-path: In-Reply-To: <1271248719-21488-1-git-send-email-jblunck@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org The BKL is still used in ext2_put_super(), ext2_fill_super(), ext2_sync_fs() ext2_remount() and ext2_write_inode(). From these calls ext2_put_super(), ext2_fill_super() and ext2_remount() are protected against each other by the struct super_block s_umount rw semaphore. The call in ext2_write_inode() could only protect the modification of the ext2_sb_info through ext2_update_dynamic_rev() against concurrent ext2_sync_fs() or ext2_remount(). ext2_fill_super() and ext2_put_super() can be left out because you need a valid filesystem reference in all three cases, which you do not have when you are one of these functions. If the BKL is only protecting the modification of the ext2_sb_info it can safely be removed since this is protected by the struct ext2_sb_info s_lock. Signed-off-by: Jan Blunck Cc: Jan Kara --- fs/ext2/inode.c | 3 --- fs/ext2/super.c | 13 ------------- 2 files changed, 0 insertions(+), 16 deletions(-) diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 5d15442..b90c3bf 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -22,7 +22,6 @@ * Assorted race fixes, rewrite of ext2_get_block() by Al Viro, 2000 */ -#include #include #include #include @@ -1406,13 +1405,11 @@ static int __ext2_write_inode(struct inode *inode, int do_sync) /* If this is the first large file * created, add a flag to the superblock. */ - lock_kernel(); spin_lock(&EXT2_SB(sb)->s_lock); ext2_update_dynamic_rev(sb); EXT2_SET_RO_COMPAT_FEATURE(sb, EXT2_FEATURE_RO_COMPAT_LARGE_FILE); spin_unlock(&EXT2_SB(sb)->s_lock); - unlock_kernel(); ext2_write_super(sb); } } diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 28f6560..71e9eb1 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -26,7 +26,6 @@ #include #include #include -#include #include #include #include @@ -120,8 +119,6 @@ static void ext2_put_super (struct super_block * sb) int i; struct ext2_sb_info *sbi = EXT2_SB(sb); - lock_kernel(); - if (sb->s_dirt) ext2_write_super(sb); @@ -147,8 +144,6 @@ static void ext2_put_super (struct super_block * sb) sb->s_fs_info = NULL; kfree(sbi->s_blockgroup_lock); kfree(sbi); - - unlock_kernel(); } static struct kmem_cache * ext2_inode_cachep; @@ -1170,7 +1165,6 @@ static int ext2_sync_fs(struct super_block *sb, int wait) struct ext2_sb_info *sbi = EXT2_SB(sb); struct ext2_super_block *es = EXT2_SB(sb)->s_es; - lock_kernel(); spin_lock(&sbi->s_lock); if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) { ext2_debug("setting valid to 0\n"); @@ -1178,8 +1172,6 @@ static int ext2_sync_fs(struct super_block *sb, int wait) } spin_unlock(&sbi->s_lock); ext2_sync_super(sb, es, wait); - unlock_kernel(); - return 0; } @@ -1201,7 +1193,6 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) unsigned long old_sb_flags; int err; - lock_kernel(); spin_lock(&sbi->s_lock); /* Store the old options */ @@ -1242,14 +1233,12 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) } if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { spin_unlock(&sbi->s_lock); - unlock_kernel(); return 0; } if (*flags & MS_RDONLY) { if (le16_to_cpu(es->s_state) & EXT2_VALID_FS || !(sbi->s_mount_state & EXT2_VALID_FS)) { spin_unlock(&sbi->s_lock); - unlock_kernel(); return 0; } /* @@ -1282,7 +1271,6 @@ static int ext2_remount (struct super_block * sb, int * flags, char * data) spin_unlock(&sbi->s_lock); ext2_write_super(sb); } - unlock_kernel(); return 0; restore_opts: sbi->s_mount_opt = old_opts.s_mount_opt; @@ -1290,7 +1278,6 @@ restore_opts: sbi->s_resgid = old_opts.s_resgid; sb->s_flags = old_sb_flags; spin_unlock(&sbi->s_lock); - unlock_kernel(); return err; } -- 1.6.4.2