From d5c1207017cd8387b4d3224dd7ab6cf5cd7f1c9a Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Thu, 28 Feb 2013 10:04:33 +0000 Subject: [PATCH] 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 Signed-off-by: Josef Bacik --- fs/btrfs/ctree.h | 9 ++++-- fs/btrfs/extent-tree.c | 65 ++++++++++++++++++++++++++++++++++-------- fs/btrfs/ioctl.c | 62 ++++++++++++++++++++++++++++------------ fs/btrfs/transaction.c | 4 +-- fs/btrfs/transaction.h | 1 + 5 files changed, 105 insertions(+), 36 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index ae8dcc406805..0d82922179db 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -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); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 5681a91ed400..7cb9d734f6e5 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -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); } /** diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 8dcd4ff0c3a5..56d92549389c 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -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 @@ fail: 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); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 71de435a291e..f11c2e0a3746 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -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 @@ no_free_objectid: 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; } diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index 5f67fba07ab4..3c8e0d25c8e4 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -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; -- 2.39.5