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 c1183f9f69dc..b879f1ba3439 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;
 }