btrfs: kill magical embedded struct superblock
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 9864cec..9552afc2 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1219,7 +1219,7 @@
* right now this just gets used so that a root has its own devid
* for stat. It may be used for more later
*/
- struct super_block anon_super;
+ dev_t anon_dev;
};
struct btrfs_ioctl_defrag_range_args {
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 1ac8db5d..b231ae1 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1077,12 +1077,7 @@
init_completion(&root->kobj_unregister);
root->defrag_running = 0;
root->root_key.objectid = objectid;
- root->anon_super.s_root = NULL;
- root->anon_super.s_dev = 0;
- INIT_LIST_HEAD(&root->anon_super.s_list);
- INIT_LIST_HEAD(&root->anon_super.s_instances);
- init_rwsem(&root->anon_super.s_umount);
-
+ root->anon_dev = 0;
return 0;
}
@@ -1311,7 +1306,7 @@
spin_lock_init(&root->cache_lock);
init_waitqueue_head(&root->cache_wait);
- ret = set_anon_super(&root->anon_super, NULL);
+ ret = get_anon_bdev(&root->anon_dev);
if (ret)
goto fail;
@@ -2393,10 +2388,8 @@
{
iput(root->cache_inode);
WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
- if (root->anon_super.s_dev) {
- down_write(&root->anon_super.s_umount);
- kill_anon_super(&root->anon_super);
- }
+ if (root->anon_dev)
+ free_anon_bdev(root->anon_dev);
free_extent_buffer(root->node);
free_extent_buffer(root->commit_root);
kfree(root->free_ino_ctl);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index cb170ca..ecf0fac 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6900,7 +6900,7 @@
{
struct inode *inode = dentry->d_inode;
generic_fillattr(inode, stat);
- stat->dev = BTRFS_I(inode)->root->anon_super.s_dev;
+ stat->dev = BTRFS_I(inode)->root->anon_dev;
stat->blksize = PAGE_CACHE_SIZE;
stat->blocks = (inode_get_bytes(inode) +
BTRFS_I(inode)->delalloc_bytes) >> 9;
diff --git a/fs/super.c b/fs/super.c
index 444da95..263edeb 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -693,7 +693,7 @@
static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */
static int unnamed_dev_start = 0; /* don't bother trying below it */
-int set_anon_super(struct super_block *s, void *data)
+int get_anon_bdev(dev_t *p)
{
int dev;
int error;
@@ -720,23 +720,37 @@
spin_unlock(&unnamed_dev_lock);
return -EMFILE;
}
- s->s_dev = MKDEV(0, dev & MINORMASK);
- s->s_bdi = &noop_backing_dev_info;
+ *p = MKDEV(0, dev & MINORMASK);
return 0;
}
+EXPORT_SYMBOL(get_anon_bdev);
+
+void free_anon_bdev(dev_t dev)
+{
+ int slot = MINOR(dev);
+ spin_lock(&unnamed_dev_lock);
+ ida_remove(&unnamed_dev_ida, slot);
+ if (slot < unnamed_dev_start)
+ unnamed_dev_start = slot;
+ spin_unlock(&unnamed_dev_lock);
+}
+EXPORT_SYMBOL(free_anon_bdev);
+
+int set_anon_super(struct super_block *s, void *data)
+{
+ int error = get_anon_bdev(&s->s_dev);
+ if (!error)
+ s->s_bdi = &noop_backing_dev_info;
+ return error;
+}
EXPORT_SYMBOL(set_anon_super);
void kill_anon_super(struct super_block *sb)
{
- int slot = MINOR(sb->s_dev);
-
+ dev_t dev = sb->s_dev;
generic_shutdown_super(sb);
- spin_lock(&unnamed_dev_lock);
- ida_remove(&unnamed_dev_ida, slot);
- if (slot < unnamed_dev_start)
- unnamed_dev_start = slot;
- spin_unlock(&unnamed_dev_lock);
+ free_anon_bdev(dev);
}
EXPORT_SYMBOL(kill_anon_super);