diff mbox series

[37/44] btrfs: hold a ref on the root in open_ctree

Message ID	20200124143301.2186319-38-josef@toxicpanda.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <SRS0=Oo12=3N=vger.kernel.org=linux-btrfs-owner@kernel.org> From: Josef Bacik <josef@toxicpanda.com> To: kernel-team@fb.com, linux-btrfs@vger.kernel.org Subject: [PATCH 37/44] btrfs: hold a ref on the root in open_ctree Date: Fri, 24 Jan 2020 09:32:54 -0500 Message-Id: <20200124143301.2186319-38-josef@toxicpanda.com> In-Reply-To: <20200124143301.2186319-1-josef@toxicpanda.com> References: <20200124143301.2186319-1-josef@toxicpanda.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk
Series	Cleanup how we handle root refs, part 1 \| expand [00/44,v5] Cleanup how we handle root refs, part 1 [01/44] btrfs: push __setup_root into btrfs_alloc_root [02/44] btrfs: move fs root init stuff into btrfs_init_fs_root [03/44] btrfs: make btrfs_find_orphan_roots use btrfs_get_fs_root [04/44] btrfs: export and use btrfs_read_tree_root [05/44] btrfs: make relocation use btrfs_read_tree_root() [06/44] btrfs: kill btrfs_read_fs_root [07/44] btrfs: kill the btrfs_read_fs_root_no_name helper [08/44] btrfs: make the fs root init functions static [09/44] btrfs: handle NULL roots in btrfs_put/btrfs_grab_fs_root [10/44] btrfs: hold a ref on fs roots while they're in the radix tree [11/44] btrfs: hold a ref on the root in resolve_indirect_ref [12/44] btrfs: hold a root ref in btrfs_get_dentry [13/44] btrfs: hold a ref on the root in __btrfs_run_defrag_inode [14/44] btrfs: hold a ref on the root in fixup_tree_root_location [15/44] btrfs: hold a ref on the root in create_subvol [16/44] btrfs: hold a ref on the root in search_ioctl [17/44] btrfs: hold a ref on the root in btrfs_search_path_in_tree [18/44] btrfs: hold a ref on the root in btrfs_search_path_in_tree_user [19/44] btrfs: hold a ref on the root in btrfs_ioctl_get_subvol_info [20/44] btrfs: hold ref on root in btrfs_ioctl_default_subvol [21/44] btrfs: hold a ref on the root in build_backref_tree [22/44] btrfs: hold a ref on the root in prepare_to_merge [23/44] btrfs: hold a ref on the root in merge_reloc_roots [24/44] btrfs: hold a ref on the root in record_reloc_root_in_trans [25/44] btrfs: hold a ref on the root in find_data_references [26/44] btrfs: hold a ref on the root in create_reloc_inode [27/44] btrfs: hold a ref on the root in btrfs_recover_relocation [28/44] btrfs: push grab_fs_root into read_fs_root [29/44] btrfs: hold a ref for the root in btrfs_find_orphan_roots [30/44] btrfs: hold a ref on the root in scrub_print_warning_inode [31/44] btrfs: hold a ref on the root in btrfs_ioctl_send [32/44] btrfs: hold a ref on the root in get_subvol_name_from_objectid [33/44] btrfs: hold a ref on the root in create_pending_snapshot [34/44] btrfs: hold a ref on the root in btrfs_recover_log_trees [35/44] btrfs: hold a ref on the root in btrfs_check_uuid_tree_entry [36/44] btrfs: move free_fs_info [37/44] btrfs: hold a ref on the root in open_ctree [38/44] btrfs: use btrfs_put_fs_root to free roots always [39/44] btrfs: push btrfs_grab_fs_root into btrfs_get_fs_root [40/44] btrfs: free more things in btrfs_free_fs_info [41/44] btrfs: move fs_info init work into it's own helper function [42/44] btrfs: make the init of static elements in fs_info separate [43/44] btrfs: add a leak check for roots [44/44] btrfs: rename btrfs_put_fs_root and btrfs_grab_fs_root

Commit Message

Josef Bacik Jan. 24, 2020, 2:32 p.m. UTC

We lookup the fs_root and put it in our fs_info directly, we should hold
a ref on this root for the lifetime of the fs_info.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/disk-io.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff mbox series

Patch

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index c605be6ba889..433c29ddfca7 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1537,6 +1537,7 @@  void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
 	kfree(fs_info->free_space_root);
 	kfree(fs_info->super_copy);
 	kfree(fs_info->super_for_commit);
+	btrfs_put_fs_root(fs_info->fs_root);
 	kvfree(fs_info);
 }
 
@@ -3203,6 +3204,13 @@  int __cold open_ctree(struct super_block *sb,
 		goto fail_qgroup;
 	}
 
+	if (!btrfs_grab_fs_root(fs_info->fs_root)) {
+		fs_info->fs_root = NULL;
+		err = -ENOENT;
+		btrfs_warn(fs_info, "failed to grab a ref on the fs tree");
+		goto fail_qgroup;
+	}
+
 	if (sb_rdonly(sb))
 		return 0;