diff options
| -rw-r--r-- | fs/btrfs/qgroup.c | 87 |
1 files changed, 61 insertions, 26 deletions
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index cfe2a6ed6229..da38b38cc6ad 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -180,30 +180,40 @@ static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info, return NULL; } -/* must be called with qgroup_lock held */ +/* + * Add qgroup to the filesystem's qgroup tree. + * + * Must be called with qgroup_lock held and @prealloc preallocated. + * + * The control on the lifespan of @prealloc would be transfered to this + * function, thus caller should no longer touch @prealloc. + */ static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info, + struct btrfs_qgroup *prealloc, u64 qgroupid) { struct rb_node **p = &fs_info->qgroup_tree.rb_node; struct rb_node *parent = NULL; struct btrfs_qgroup *qgroup; + /* Caller must have pre-allocated @prealloc. */ + ASSERT(prealloc); + while (*p) { parent = *p; qgroup = rb_entry(parent, struct btrfs_qgroup, node); - if (qgroup->qgroupid < qgroupid) + if (qgroup->qgroupid < qgroupid) { p = &(*p)->rb_left; - else if (qgroup->qgroupid > qgroupid) + } else if (qgroup->qgroupid > qgroupid) { p = &(*p)->rb_right; - else + } else { + kfree(prealloc); return qgroup; + } } - qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC); - if (!qgroup) - return ERR_PTR(-ENOMEM); - + qgroup = prealloc; qgroup->qgroupid = qgroupid; INIT_LIST_HEAD(&qgroup->groups); INIT_LIST_HEAD(&qgroup->members); @@ -436,11 +446,14 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info) qgroup_mark_inconsistent(fs_info); } if (!qgroup) { - qgroup = add_qgroup_rb(fs_info, found_key.offset); - if (IS_ERR(qgroup)) { - ret = PTR_ERR(qgroup); + struct btrfs_qgroup *prealloc; + + prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL); + if (!prealloc) { + ret = -ENOMEM; goto out; } + qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset); } ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); if (ret < 0) @@ -961,6 +974,7 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info) struct btrfs_key key; struct btrfs_key found_key; struct btrfs_qgroup *qgroup = NULL; + struct btrfs_qgroup *prealloc = NULL; struct btrfs_trans_handle *trans = NULL; struct ulist *ulist = NULL; int ret = 0; @@ -1096,6 +1110,15 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info) /* Release locks on tree_root before we access quota_root */ btrfs_release_path(path); + /* We should not have a stray @prealloc pointer. */ + ASSERT(prealloc == NULL); + prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS); + if (!prealloc) { + ret = -ENOMEM; + btrfs_abort_transaction(trans, ret); + goto out_free_path; + } + ret = add_qgroup_item(trans, quota_root, found_key.offset); if (ret) { @@ -1103,7 +1126,8 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info) goto out_free_path; } - qgroup = add_qgroup_rb(fs_info, found_key.offset); + qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset); + prealloc = NULL; if (IS_ERR(qgroup)) { ret = PTR_ERR(qgroup); btrfs_abort_transaction(trans, ret); @@ -1146,12 +1170,14 @@ out_add_root: goto out_free_path; } - qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID); - if (IS_ERR(qgroup)) { - ret = PTR_ERR(qgroup); - btrfs_abort_transaction(trans, ret); + ASSERT(prealloc == NULL); + prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS); + if (!prealloc) { + ret = -ENOMEM; goto out_free_path; } + qgroup = add_qgroup_rb(fs_info, prealloc, BTRFS_FS_TREE_OBJECTID); + prealloc = NULL; ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); if (ret < 0) { btrfs_abort_transaction(trans, ret); @@ -1224,6 +1250,7 @@ out: else if (trans) ret = btrfs_end_transaction(trans); ulist_free(ulist); + kfree(prealloc); return ret; } @@ -1581,6 +1608,7 @@ int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid) struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *quota_root; struct btrfs_qgroup *qgroup; + struct btrfs_qgroup *prealloc = NULL; int ret = 0; mutex_lock(&fs_info->qgroup_ioctl_lock); @@ -1595,21 +1623,25 @@ int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid) goto out; } + prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS); + if (!prealloc) { + ret = -ENOMEM; + goto out; + } + ret = add_qgroup_item(trans, quota_root, qgroupid); if (ret) goto out; spin_lock(&fs_info->qgroup_lock); - qgroup = add_qgroup_rb(fs_info, qgroupid); + qgroup = add_qgroup_rb(fs_info, prealloc, qgroupid); spin_unlock(&fs_info->qgroup_lock); + prealloc = NULL; - if (IS_ERR(qgroup)) { - ret = PTR_ERR(qgroup); - goto out; - } ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); out: mutex_unlock(&fs_info->qgroup_ioctl_lock); + kfree(prealloc); return ret; } @@ -2854,10 +2886,15 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, struct btrfs_root *quota_root; struct btrfs_qgroup *srcgroup; struct btrfs_qgroup *dstgroup; + struct btrfs_qgroup *prealloc; bool need_rescan = false; u32 level_size = 0; u64 nums; + prealloc = kzalloc(sizeof(*prealloc), GFP_NOFS); + if (!prealloc) + return -ENOMEM; + /* * There are only two callers of this function. * @@ -2935,11 +2972,8 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, spin_lock(&fs_info->qgroup_lock); - dstgroup = add_qgroup_rb(fs_info, objectid); - if (IS_ERR(dstgroup)) { - ret = PTR_ERR(dstgroup); - goto unlock; - } + dstgroup = add_qgroup_rb(fs_info, prealloc, objectid); + prealloc = NULL; if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) { dstgroup->lim_flags = inherit->lim.flags; @@ -3050,6 +3084,7 @@ out: mutex_unlock(&fs_info->qgroup_ioctl_lock); if (need_rescan) qgroup_mark_inconsistent(fs_info); + kfree(prealloc); return ret; } |