ufs: sb mutex merge + mutex_destroy

Commit 788257d6101d ("ufs: remove the BKL") replaced BKL with mutex
protection using functions lock_ufs, unlock_ufs and struct mutex 'mutex'
in sb_info.

Commit b6963327e052 ("ufs: drop lock/unlock super") removed lock/unlock
super and added struct mutex 's_lock' in sb_info.

Those 2 mutexes are generally locked/unlocked at the same time except in
allocation (balloc, ialloc).

This patch merges the 2 mutexes and propagates first commit solution.
It also adds mutex destruction before kfree during ufs_fill_super
failure and ufs_put_super.

[akpm@linux-foundation.org: avoid ifdefs, return -EROFS not -EINVAL]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: "Chen, Jet" <jet.chen@intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 10 insertions, 18 deletions

diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index c1183f9..b879f1b 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -697,7 +697,6 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
 	unsigned flags;
 
 	lock_ufs(sb);
-	mutex_lock(&UFS_SB(sb)->s_lock);
 
 	UFSD("ENTER\n");
 
@@ -715,7 +714,6 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
 	ufs_put_cstotal(sb);
 
 	UFSD("EXIT\n");
-	mutex_unlock(&UFS_SB(sb)->s_lock);
 	unlock_ufs(sb);
 
 	return 0;
@@ -760,6 +758,7 @@ static void ufs_put_super(struct super_block *sb)
 
 	ubh_brelse_uspi (sbi->s_uspi);
 	kfree (sbi->s_uspi);
+	mutex_destroy(&sbi->mutex);
 	kfree (sbi);
 	sb->s_fs_info = NULL;
 	UFSD("EXIT\n");
@@ -786,6 +785,14 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
 	flags = 0;
 	
 	UFSD("ENTER\n");
+
+#ifndef CONFIG_UFS_FS_WRITE
+	if (!(sb->s_flags & MS_RDONLY)) {
+		printk("ufs was compiled with read-only support, "
+		       "can't be mounted as read-write\n");
+		return -EROFS;
+	}
+#endif
 		
 	sbi = kzalloc(sizeof(struct ufs_sb_info), GFP_KERNEL);
 	if (!sbi)
@@ -795,15 +802,7 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
 
 	UFSD("flag %u\n", (int)(sb->s_flags & MS_RDONLY));
 	
-#ifndef CONFIG_UFS_FS_WRITE
-	if (!(sb->s_flags & MS_RDONLY)) {
-		printk("ufs was compiled with read-only support, "
-		"can't be mounted as read-write\n");
-		goto failed;
-	}
-#endif
 	mutex_init(&sbi->mutex);
-	mutex_init(&sbi->s_lock);
 	spin_lock_init(&sbi->work_lock);
 	INIT_DELAYED_WORK(&sbi->sync_work, delayed_sync_fs);
 	/*
@@ -1257,6 +1256,7 @@ magic_found:
 	return 0;
 
 failed:
+	mutex_destroy(&sbi->mutex);
 	if (ubh)
 		ubh_brelse_uspi (uspi);
 	kfree (uspi);
@@ -1280,7 +1280,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 
 	sync_filesystem(sb);
 	lock_ufs(sb);
-	mutex_lock(&UFS_SB(sb)->s_lock);
 	uspi = UFS_SB(sb)->s_uspi;
 	flags = UFS_SB(sb)->s_flags;
 	usb1 = ubh_get_usb_first(uspi);
@@ -1294,7 +1293,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 	new_mount_opt = 0;
 	ufs_set_opt (new_mount_opt, ONERROR_LOCK);
 	if (!ufs_parse_options (data, &new_mount_opt)) {
-		mutex_unlock(&UFS_SB(sb)->s_lock);
 		unlock_ufs(sb);
 		return -EINVAL;
 	}
@@ -1302,14 +1300,12 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 		new_mount_opt |= ufstype;
 	} else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) {
 		printk("ufstype can't be changed during remount\n");
-		mutex_unlock(&UFS_SB(sb)->s_lock);
 		unlock_ufs(sb);
 		return -EINVAL;
 	}
 
 	if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
 		UFS_SB(sb)->s_mount_opt = new_mount_opt;
-		mutex_unlock(&UFS_SB(sb)->s_lock);
 		unlock_ufs(sb);
 		return 0;
 	}
@@ -1334,7 +1330,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 #ifndef CONFIG_UFS_FS_WRITE
 		printk("ufs was compiled with read-only support, "
 		"can't be mounted as read-write\n");
-		mutex_unlock(&UFS_SB(sb)->s_lock);
 		unlock_ufs(sb);
 		return -EINVAL;
 #else
@@ -1344,13 +1339,11 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 		    ufstype != UFS_MOUNT_UFSTYPE_SUNx86 &&
 		    ufstype != UFS_MOUNT_UFSTYPE_UFS2) {
 			printk("this ufstype is read-only supported\n");
-			mutex_unlock(&UFS_SB(sb)->s_lock);
 			unlock_ufs(sb);
 			return -EINVAL;
 		}
 		if (!ufs_read_cylinder_structures(sb)) {
 			printk("failed during remounting\n");
-			mutex_unlock(&UFS_SB(sb)->s_lock);
 			unlock_ufs(sb);
 			return -EPERM;
 		}
@@ -1358,7 +1351,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
 #endif
 	}
 	UFS_SB(sb)->s_mount_opt = new_mount_opt;
-	mutex_unlock(&UFS_SB(sb)->s_lock);
 	unlock_ufs(sb);
 	return 0;
 }