Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6

[linux.git] / fs / super.c

diff --git a/fs/super.c b/fs/super.c
index 9b780c42d845ca57cc40faa24814533a80ef29d1..47e554c12e768bc0c5b0ad10b10d3a3a92a90e46 100644 (file)
--- a/fs/super.c
+++ b/fs/super.c
@@ -49,11 +49,12 @@ DEFINE_SPINLOCK(sb_lock);
 
 /**
  *     alloc_super     -       create new superblock
+ *     @type:  filesystem type superblock should belong to
  *
  *     Allocates and initializes a new &struct super_block.  alloc_super()
  *     returns a pointer new superblock or %NULL if allocation had failed.
  */
-static struct super_block *alloc_super(void)
+static struct super_block *alloc_super(struct file_system_type *type)
 {
        struct super_block *s = kzalloc(sizeof(struct super_block),  GFP_USER);
        static struct super_operations default_op;
@@ -72,6 +73,13 @@ static struct super_block *alloc_super(void)
                INIT_LIST_HEAD(&s->s_inodes);
                init_rwsem(&s->s_umount);
                mutex_init(&s->s_lock);
+               lockdep_set_class(&s->s_umount, &type->s_umount_key);
+               /*
+                * The locking rules for s_lock are up to the
+                * filesystem. For example ext3fs has different
+                * lock ordering than usbfs:
+                */
+               lockdep_set_class(&s->s_lock, &type->s_lock_key);
                down_write(&s->s_umount);
                s->s_count = S_BIAS;
                atomic_set(&s->s_active, 1);
@@ -191,7 +199,7 @@ EXPORT_SYMBOL(deactivate_super);
  *     success, 0 if we had failed (superblock contents was already dead or
  *     dying when grab_super() had been called).
  */
-static int grab_super(struct super_block *s)
+static int grab_super(struct super_block *s) __releases(sb_lock)
 {
        s->s_count++;
        spin_unlock(&sb_lock);
@@ -212,6 +220,37 @@ static int grab_super(struct super_block *s)
        return 0;
 }
 
+/*
+ * Write out and wait upon all dirty data associated with this
+ * superblock.  Filesystem data as well as the underlying block
+ * device.  Takes the superblock lock.  Requires a second blkdev
+ * flush by the caller to complete the operation.
+ */
+void __fsync_super(struct super_block *sb)
+{
+       sync_inodes_sb(sb, 0);
+       DQUOT_SYNC(sb);
+       lock_super(sb);
+       if (sb->s_dirt && sb->s_op->write_super)
+               sb->s_op->write_super(sb);
+       unlock_super(sb);
+       if (sb->s_op->sync_fs)
+               sb->s_op->sync_fs(sb, 1);
+       sync_blockdev(sb->s_bdev);
+       sync_inodes_sb(sb, 1);
+}
+
+/*
+ * Write out and wait upon all dirty data associated with this
+ * superblock.  Filesystem data as well as the underlying block
+ * device.  Takes the superblock lock.
+ */
+int fsync_super(struct super_block *sb)
+{
+       __fsync_super(sb);
+       return sync_blockdev(sb->s_bdev);
+}
+
 /**
  *     generic_shutdown_super  -       common helper for ->kill_sb()
  *     @sb: superblock to kill
@@ -221,17 +260,17 @@ static int grab_super(struct super_block *s)
  *     that need destruction out of superblock, call generic_shutdown_super()
  *     and release aforementioned objects.  Note: dentries and inodes _are_
  *     taken care of and do not need specific handling.
+ *
+ *     Upon calling this function, the filesystem may no longer alter or
+ *     rearrange the set of dentries belonging to this super_block, nor may it
+ *     change the attachments of dentries to inodes.
  */
 void generic_shutdown_super(struct super_block *sb)
 {
-       struct dentry *root = sb->s_root;
        struct super_operations *sop = sb->s_op;
 
-       if (root) {
-               sb->s_root = NULL;
-               shrink_dcache_parent(root);
-               shrink_dcache_sb(sb);
-               dput(root);
+       if (sb->s_root) {
+               shrink_dcache_for_umount(sb);
                fsync_super(sb);
                lock_super(sb);
                sb->s_flags &= ~MS_ACTIVE;
@@ -295,7 +334,7 @@ retry:
        }
        if (!s) {
                spin_unlock(&sb_lock);
-               s = alloc_super();
+               s = alloc_super(type);
                if (!s)
                        return ERR_PTR(-ENOMEM);
                goto retry;
@@ -532,8 +571,10 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
 {
        int retval;
        
+#ifdef CONFIG_BLOCK
        if (!(flags & MS_RDONLY) && bdev_read_only(sb->s_bdev))
                return -EACCES;
+#endif
        if (flags & MS_RDONLY)
                acct_auto_close(sb);
        shrink_dcache_sb(sb);
@@ -653,6 +694,7 @@ void kill_litter_super(struct super_block *sb)
 
 EXPORT_SYMBOL(kill_litter_super);
 
+#ifdef CONFIG_BLOCK
 static int set_bdev_super(struct super_block *s, void *data)
 {
        s->s_bdev = data;
@@ -748,6 +790,7 @@ void kill_block_super(struct super_block *sb)
 }
 
 EXPORT_SYMBOL(kill_block_super);
+#endif
 
 int get_sb_nodev(struct file_system_type *fs_type,
        int flags, void *data,