Btrfs: fix wrong reserved space in qgroup during snap/subv creation

There are two problems in the space reservation of the snapshot/
subvolume creation.
- don't reserve the space for the root item insertion
- the space which is reserved in the qgroup is different with
  the free space reservation. we need reserve free space for
  7 items, but in qgroup reservation, we need reserve space only
  for 3 items.

So we implement new metadata reservation functions for the
snapshot/subvolume creation.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This commit is contained in:
Miao Xie 2013-02-28 10:04:33 +00:00 committed by Josef Bacik
parent e9662f701c
commit d5c1207017
5 changed files with 105 additions and 36 deletions

View file

@ -3106,8 +3106,13 @@ void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
struct inode *inode);
void btrfs_orphan_release_metadata(struct inode *inode);
int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
struct btrfs_pending_snapshot *pending);
int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
struct btrfs_block_rsv *rsv,
int nitems,
u64 *qgroup_reserved);
void btrfs_subvolume_release_metadata(struct btrfs_root *root,
struct btrfs_block_rsv *rsv,
u64 qgroup_reserved);
int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes);
void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes);
int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes);

View file

@ -4560,19 +4560,60 @@ void btrfs_orphan_release_metadata(struct inode *inode)
btrfs_block_rsv_release(root, root->orphan_block_rsv, num_bytes);
}
int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
struct btrfs_pending_snapshot *pending)
/*
* btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
* root: the root of the parent directory
* rsv: block reservation
* items: the number of items that we need do reservation
* qgroup_reserved: used to return the reserved size in qgroup
*
* This function is used to reserve the space for snapshot/subvolume
* creation and deletion. Those operations are different with the
* common file/directory operations, they change two fs/file trees
* and root tree, the number of items that the qgroup reserves is
* different with the free space reservation. So we can not use
* the space reseravtion mechanism in start_transaction().
*/
int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
struct btrfs_block_rsv *rsv,
int items,
u64 *qgroup_reserved)
{
struct btrfs_root *root = pending->root;
struct btrfs_block_rsv *src_rsv = get_block_rsv(trans, root);
struct btrfs_block_rsv *dst_rsv = &pending->block_rsv;
/*
* two for root back/forward refs, two for directory entries,
* one for root of the snapshot and one for parent inode.
*/
u64 num_bytes = btrfs_calc_trans_metadata_size(root, 6);
dst_rsv->space_info = src_rsv->space_info;
return block_rsv_migrate_bytes(src_rsv, dst_rsv, num_bytes);
u64 num_bytes;
int ret;
if (root->fs_info->quota_enabled) {
/* One for parent inode, two for dir entries */
num_bytes = 3 * root->leafsize;
ret = btrfs_qgroup_reserve(root, num_bytes);
if (ret)
return ret;
} else {
num_bytes = 0;
}
*qgroup_reserved = num_bytes;
num_bytes = btrfs_calc_trans_metadata_size(root, items);
rsv->space_info = __find_space_info(root->fs_info,
BTRFS_BLOCK_GROUP_METADATA);
ret = btrfs_block_rsv_add(root, rsv, num_bytes,
BTRFS_RESERVE_FLUSH_ALL);
if (ret) {
if (*qgroup_reserved)
btrfs_qgroup_free(root, *qgroup_reserved);
}
return ret;
}
void btrfs_subvolume_release_metadata(struct btrfs_root *root,
struct btrfs_block_rsv *rsv,
u64 qgroup_reserved)
{
btrfs_block_rsv_release(root, rsv, (u64)-1);
if (qgroup_reserved)
btrfs_qgroup_free(root, qgroup_reserved);
}
/**

View file

@ -363,7 +363,7 @@ static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
return 0;
}
static noinline int create_subvol(struct btrfs_root *root,
static noinline int create_subvol(struct inode *dir,
struct dentry *dentry,
char *name, int namelen,
u64 *async_transid,
@ -374,32 +374,39 @@ static noinline int create_subvol(struct btrfs_root *root,
struct btrfs_root_item root_item;
struct btrfs_inode_item *inode_item;
struct extent_buffer *leaf;
struct btrfs_root *root = BTRFS_I(dir)->root;
struct btrfs_root *new_root;
struct dentry *parent = dentry->d_parent;
struct inode *dir;
struct btrfs_block_rsv block_rsv;
struct timespec cur_time = CURRENT_TIME;
int ret;
int err;
u64 objectid;
u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
u64 index = 0;
u64 qgroup_reserved;
uuid_le new_uuid;
ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
if (ret)
return ret;
dir = parent->d_inode;
btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
/*
* 1 - inode item
* 2 - refs
* 1 - root item
* 2 - dir items
* The same as the snapshot creation, please see the comment
* of create_snapshot().
*/
trans = btrfs_start_transaction(root, 6);
if (IS_ERR(trans))
return PTR_ERR(trans);
ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
7, &qgroup_reserved);
if (ret)
return ret;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto out;
}
trans->block_rsv = &block_rsv;
trans->bytes_reserved = block_rsv.size;
ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
if (ret)
@ -515,6 +522,8 @@ static noinline int create_subvol(struct btrfs_root *root,
BUG_ON(ret);
fail:
trans->block_rsv = NULL;
trans->bytes_reserved = 0;
if (async_transid) {
*async_transid = trans->transid;
err = btrfs_commit_transaction_async(trans, root, 1);
@ -526,7 +535,8 @@ static noinline int create_subvol(struct btrfs_root *root,
if (!ret)
d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
out:
btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
return ret;
}
@ -549,21 +559,31 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
btrfs_init_block_rsv(&pending_snapshot->block_rsv,
BTRFS_BLOCK_RSV_TEMP);
/*
* 1 - parent dir inode
* 2 - dir entries
* 1 - root item
* 2 - root ref/backref
* 1 - root of snapshot
*/
ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
&pending_snapshot->block_rsv, 7,
&pending_snapshot->qgroup_reserved);
if (ret)
goto out;
pending_snapshot->dentry = dentry;
pending_snapshot->root = root;
pending_snapshot->readonly = readonly;
pending_snapshot->dir = dir;
pending_snapshot->inherit = inherit;
trans = btrfs_start_transaction(root->fs_info->extent_root, 6);
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
goto fail;
}
ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
BUG_ON(ret);
spin_lock(&root->fs_info->trans_lock);
list_add(&pending_snapshot->list,
&trans->transaction->pending_snapshots);
@ -600,6 +620,10 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
d_instantiate(dentry, inode);
ret = 0;
fail:
btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
&pending_snapshot->block_rsv,
pending_snapshot->qgroup_reserved);
out:
kfree(pending_snapshot);
return ret;
}
@ -733,8 +757,8 @@ static noinline int btrfs_mksubvol(struct path *parent,
error = create_snapshot(snap_src, dir, dentry, name, namelen,
async_transid, readonly, inherit);
} else {
error = create_subvol(BTRFS_I(dir)->root, dentry,
name, namelen, async_transid, inherit);
error = create_subvol(dir, dentry, name, namelen,
async_transid, inherit);
}
if (!error)
fsnotify_mkdir(dir, dentry);

View file

@ -1082,7 +1082,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
path = btrfs_alloc_path();
if (!path) {
ret = pending->error = -ENOMEM;
goto path_alloc_fail;
return ret;
}
new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
@ -1279,8 +1279,6 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
kfree(new_root_item);
root_item_alloc_fail:
btrfs_free_path(path);
path_alloc_fail:
btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1);
return ret;
}

View file

@ -90,6 +90,7 @@ struct btrfs_pending_snapshot {
struct btrfs_qgroup_inherit *inherit;
/* block reservation for the operation */
struct btrfs_block_rsv block_rsv;
u64 qgroup_reserved;
/* extra metadata reseration for relocation */
int error;
bool readonly;