Revert "ANDROID: incremental-fs: fix mount_fs issue"

This reverts three increment-fs commits:
d5faa13b59
10412e10c6
7ad88c9349

This is to fix the incrementalinstall test.
Can now install the same apk twice, and repeated installs are stable.

Bug: 217661925
Bug: 219731048
Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Change-Id: Ia8488d728218881ed17e4d68cab21b0b152e3ca4

fs/incfs/vfs.c

@@ -43,8 +43,7 @@ static int dir_link(struct dentry *old_dentry, struct inode *dir,
 			 struct dentry *new_dentry);
 static int dir_rmdir(struct inode *dir, struct dentry *dentry);
 static int dir_rename(struct inode *old_dir, struct dentry *old_dentry,
-		struct inode *new_dir, struct dentry *new_dentry,
+		struct inode *new_dir, struct dentry *new_dentry);
-		unsigned int flags);
 
 static int file_open(struct inode *inode, struct file *file);
 static int file_release(struct inode *inode, struct file *file);
@@ -87,7 +86,7 @@ static int dir_rename_wrap(struct user_namespace *ns, struct inode *old_dir,
 			   struct dentry *old_dentry, struct inode *new_dir,
 			   struct dentry *new_dentry, unsigned int flags)
 {
-	return dir_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
+	return dir_rename(old_dir, old_dentry, new_dir, new_dentry);
 }
 
 static const struct inode_operations incfs_dir_inode_ops = {
@@ -399,7 +398,7 @@ static int iterate_incfs_dir(struct file *file, struct dir_context *ctx)
 	struct mount_info *mi = get_mount_info(file_superblock(file));
 	bool root;
 
-	if (!dir || !mi) {
+	if (!dir) {
 		error = -EBADF;
 		goto out;
 	}
@@ -1331,8 +1330,7 @@ path_err:
 }
 
 static int dir_rename(struct inode *old_dir, struct dentry *old_dentry,
-		struct inode *new_dir, struct dentry *new_dentry,
+		struct inode *new_dir, struct dentry *new_dentry)
-		unsigned int flags)
 {
 	struct mount_info *mi = get_mount_info(old_dir->i_sb);
 	struct dentry *backing_old_dentry;
@@ -1344,9 +1342,6 @@ static int dir_rename(struct inode *old_dir, struct dentry *old_dentry,
 	struct renamedata rd = {};
 	int error = 0;
 
-	if (!mi)
-		return -EBADF;
-
 	error = mutex_lock_interruptible(&mi->mi_dir_struct_mutex);
 	if (error)
 		return error;
@@ -1390,11 +1385,6 @@ static int dir_rename(struct inode *old_dir, struct dentry *old_dentry,
 	rd.old_dentry	= backing_old_dentry;
 	rd.new_dir	= d_inode(backing_new_dir_dentry);
 	rd.new_dentry	= backing_new_dentry;
-	rd.flags	= flags;
-	rd.old_mnt_userns = &init_user_ns;
-	rd.new_mnt_userns = &init_user_ns;
-	rd.delegated_inode = NULL;
-
 	error = vfs_rename(&rd);
 	if (error)
 		goto unlock_out;
@@ -1683,9 +1673,6 @@ static ssize_t incfs_getxattr(struct dentry *d, const char *name,
 	size_t stored_size;
 	int i;
 
-	if (!mi)
-		return -EBADF;
-
 	if (di && di->backing_path.dentry)
 		return vfs_getxattr(&init_user_ns, di->backing_path.dentry, name, value, size);
 
@@ -1721,9 +1708,6 @@ static ssize_t incfs_setxattr(struct user_namespace *ns, struct dentry *d,
 	size_t *stored_size;
 	int i;
 
-	if (!mi)
-		return -EBADF;
-
 	if (di && di->backing_path.dentry)
 		return vfs_setxattr(ns, di->backing_path.dentry, name, value,
 				    size, flags);
@@ -1762,11 +1746,6 @@ static ssize_t incfs_listxattr(struct dentry *d, char *list, size_t size)
 	return vfs_listxattr(di->backing_path.dentry, list, size);
 }
 
-static int incfs_test_super(struct super_block *s, void *p)
-{
-	return s->s_fs_info != NULL;
-}
-
 struct dentry *incfs_mount_fs(struct file_system_type *type, int flags,
 			      const char *dev_name, void *data)
 {
@@ -1777,8 +1756,7 @@ struct dentry *incfs_mount_fs(struct file_system_type *type, int flags,
 	struct dentry *incomplete_dir = NULL;
 	struct super_block *src_fs_sb = NULL;
 	struct inode *root_inode = NULL;
-	struct super_block *sb = sget(type, incfs_test_super, set_anon_super,
+	struct super_block *sb = sget(type, NULL, set_anon_super, flags, NULL);
-				      flags, NULL);
 	int error = 0;
 
 	if (IS_ERR(sb))
@@ -1819,18 +1797,13 @@ struct dentry *incfs_mount_fs(struct file_system_type *type, int flags,
 	src_fs_sb = backing_dir_path.dentry->d_sb;
 	sb->s_maxbytes = src_fs_sb->s_maxbytes;
 
-	if (!sb->s_fs_info) {
+	mi = incfs_alloc_mount_info(sb, &options, &backing_dir_path);
-		mi = incfs_alloc_mount_info(sb, &options, &backing_dir_path);
 
-		if (IS_ERR_OR_NULL(mi)) {
+	if (IS_ERR_OR_NULL(mi)) {
-			error = PTR_ERR(mi);
+		error = PTR_ERR(mi);
-			pr_err("incfs: Error allocating mount info. %d\n", error);
+		pr_err("incfs: Error allocating mount info. %d\n", error);
-			mi = NULL;
+		mi = NULL;
-			goto err;
+		goto err;
-		}
-		sb->s_fs_info = mi;
-	} else {
-		mi = sb->s_fs_info;
 	}
 
 	index_dir = open_or_create_special_dir(backing_dir_path.dentry,
@@ -1855,28 +1828,26 @@ struct dentry *incfs_mount_fs(struct file_system_type *type, int flags,
 	}
 	mi->mi_incomplete_dir = incomplete_dir;
 
+	sb->s_fs_info = mi;
 	root_inode = fetch_regular_inode(sb, backing_dir_path.dentry);
 	if (IS_ERR(root_inode)) {
 		error = PTR_ERR(root_inode);
 		goto err;
 	}
 
+	sb->s_root = d_make_root(root_inode);
 	if (!sb->s_root) {
-		sb->s_root = d_make_root(root_inode);
+		error = -ENOMEM;
-		if (!sb->s_root) {
+		goto err;
-			error = -ENOMEM;
-			goto err;
-		}
-		error = incfs_init_dentry(sb->s_root, &backing_dir_path);
-		if (error)
-			goto err;
 	}
+	error = incfs_init_dentry(sb->s_root, &backing_dir_path);
+	if (error)
+		goto err;
 
-	mi->mi_backing_dir_path = backing_dir_path;
+	path_put(&backing_dir_path);
 	sb->s_flags |= SB_ACTIVE;
 
 	pr_debug("incfs: mount\n");
-	free_options(&options);
 	return dget(sb->s_root);
 err:
 	sb->s_fs_info = NULL;
@@ -1893,9 +1864,6 @@ static int incfs_remount_fs(struct super_block *sb, int *flags, char *data)
 	struct mount_info *mi = get_mount_info(sb);
 	int err = 0;
 
-	if (!mi)
-		return err;
-
 	sync_filesystem(sb);
 	err = parse_options(&options, (char *)data);
 	if (err)
@@ -1923,23 +1891,14 @@ void incfs_kill_sb(struct super_block *sb)
 	struct mount_info *mi = sb->s_fs_info;
 
 	pr_debug("incfs: unmount\n");
-	vfs_rmdir(&init_user_ns, d_inode(mi->mi_backing_dir_path.dentry),
+	generic_shutdown_super(sb);
-		  mi->mi_index_dir);
-	vfs_rmdir(&init_user_ns, d_inode(mi->mi_backing_dir_path.dentry),
-		  mi->mi_incomplete_dir);
-
-	kill_anon_super(sb);
 	incfs_free_mount_info(mi);
-	sb->s_fs_info = NULL;
 }
 
 static int show_options(struct seq_file *m, struct dentry *root)
 {
 	struct mount_info *mi = get_mount_info(root->d_sb);
 
-	if (!mi)
-		return -EBADF;
-
 	seq_printf(m, ",read_timeout_ms=%u", mi->mi_options.read_timeout_ms);
 	seq_printf(m, ",readahead=%u", mi->mi_options.readahead_pages);
 	if (mi->mi_options.read_log_pages != 0) {

fs/incfs/vfs.h

@@ -19,6 +19,7 @@ static inline struct mount_info *get_mount_info(struct super_block *sb)
 {
 	struct mount_info *result = sb->s_fs_info;
 
+	WARN_ON(!result);
 	return result;
 }