[PATCH 01/43] btrfs: push __setup_root into btrfs_alloc_root

Josef Bacik
2020-01-17T21:26:10Z

There's no reason to not init the root at alloc time, and with later
patches it actually causes problems if we error out mounting the fs
before the tree_root is init'ed because we expect it to have a valid ref
count. Fix this by pushing __setup_root into btrfs_alloc_root.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/disk-io.c | 34 +++++++++++++---------------------
1 file changed, 13 insertions(+), 21 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 5ce2801f8388..1dc33e95052b 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1130,6 +1130,7 @@ static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
u64 objectid)
{
bool dummy = test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
+ root->fs_info = fs_info;
root->node = NULL;
root->commit_root = NULL;
root->state = 0;
@@ -1198,11 +1199,11 @@ static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info,
}

static struct btrfs_root *btrfs_alloc_root(struct btrfs_fs_info *fs_info,
- gfp_t flags)
+ u64 objectid, gfp_t flags)
{
struct btrfs_root *root = kzalloc(sizeof(*root), flags);
if (root)
- root->fs_info = fs_info;
+ __setup_root(root, fs_info, objectid);
return root;
}

@@ -1215,12 +1216,11 @@ struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info)
if (!fs_info)
return ERR_PTR(-EINVAL);

- root = btrfs_alloc_root(fs_info, GFP_KERNEL);
+ root = btrfs_alloc_root(fs_info, BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
if (!root)
return ERR_PTR(-ENOMEM);

/* We don't use the stripesize in selftest, set it as sectorsize */
- __setup_root(root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
root->alloc_bytenr = 0;

return root;
@@ -1244,12 +1244,11 @@ struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
* context to avoid deadlock if reclaim happens.
*/
nofs_flag = memalloc_nofs_save();
- root = btrfs_alloc_root(fs_info, GFP_KERNEL);
+ root = btrfs_alloc_root(fs_info, objectid, GFP_KERNEL);
memalloc_nofs_restore(nofs_flag);
if (!root)
return ERR_PTR(-ENOMEM);

- __setup_root(root, fs_info, objectid);
root->root_key.objectid = objectid;
root->root_key.type = BTRFS_ROOT_ITEM_KEY;
root->root_key.offset = 0;
@@ -1309,12 +1308,10 @@ static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
struct btrfs_root *root;
struct extent_buffer *leaf;

- root = btrfs_alloc_root(fs_info, GFP_NOFS);
+ root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID, GFP_NOFS);
if (!root)
return ERR_PTR(-ENOMEM);

- __setup_root(root, fs_info, BTRFS_TREE_LOG_OBJECTID);
-
root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
root->root_key.type = BTRFS_ROOT_ITEM_KEY;
root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
@@ -1401,14 +1398,12 @@ static struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
if (!path)
return ERR_PTR(-ENOMEM);

- root = btrfs_alloc_root(fs_info, GFP_NOFS);
+ root = btrfs_alloc_root(fs_info, key->objectid, GFP_NOFS);
if (!root) {
ret = -ENOMEM;
goto alloc_fail;
}

- __setup_root(root, fs_info, key->objectid);
-
ret = btrfs_find_root(tree_root, key, path,
&root->root_item, &root->root_key);
if (ret) {
@@ -2208,12 +2203,11 @@ static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
return -EIO;
}

- log_tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
+ log_tree_root = btrfs_alloc_root(fs_info, BTRFS_TREE_LOG_OBJECTID,
+ GFP_KERNEL);
if (!log_tree_root)
return -ENOMEM;

- __setup_root(log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
-
log_tree_root->node = read_tree_block(fs_info, bytenr,
fs_info->generation + 1,
level, NULL);
@@ -2645,8 +2639,10 @@ int __cold open_ctree(struct super_block *sb,
int clear_free_space_tree = 0;
int level;

- tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
- chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info, GFP_KERNEL);
+ tree_root = fs_info->tree_root = btrfs_alloc_root(fs_info,
+ BTRFS_ROOT_TREE_OBJECTID, GFP_KERNEL);
+ chunk_root = fs_info->chunk_root = btrfs_alloc_root(fs_info,
+ BTRFS_CHUNK_TREE_OBJECTID, GFP_KERNEL);
if (!tree_root || !chunk_root) {
err = -ENOMEM;
goto fail;
@@ -2825,8 +2821,6 @@ int __cold open_ctree(struct super_block *sb,
goto fail_alloc;
}

- __setup_root(tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
-
invalidate_bdev(fs_devices->latest_bdev);

/*
@@ -3022,8 +3016,6 @@ int __cold open_ctree(struct super_block *sb,
generation = btrfs_super_chunk_root_generation(disk_super);
level = btrfs_super_chunk_root_level(disk_super);

- __setup_root(chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
-
chunk_root->node = read_tree_block(fs_info,
btrfs_super_chunk_root(disk_super),
generation, level, NULL);
--
2.24.1