// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2011 STRATO. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include "ctree.h" #include "transaction.h" #include "disk-io.h" #include "locking.h" #include "ulist.h" #include "backref.h" #include "extent_io.h" #include "qgroup.h" #include "block-group.h" #include "sysfs.h" #include "tree-mod-log.h" #include "fs.h" #include "accessors.h" #include "extent-tree.h" #include "root-tree.h" #include "tree-checker.h" enum btrfs_qgroup_mode btrfs_qgroup_mode(const struct btrfs_fs_info *fs_info) { if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) return BTRFS_QGROUP_MODE_DISABLED; if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE) return BTRFS_QGROUP_MODE_SIMPLE; return BTRFS_QGROUP_MODE_FULL; } bool btrfs_qgroup_enabled(const struct btrfs_fs_info *fs_info) { return btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_DISABLED; } bool btrfs_qgroup_full_accounting(const struct btrfs_fs_info *fs_info) { return btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL; } /* * Helpers to access qgroup reservation * * Callers should ensure the lock context and type are valid */ static u64 qgroup_rsv_total(const struct btrfs_qgroup *qgroup) { u64 ret = 0; int i; for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) ret += qgroup->rsv.values[i]; return ret; } #ifdef CONFIG_BTRFS_DEBUG static const char *qgroup_rsv_type_str(enum btrfs_qgroup_rsv_type type) { if (type == BTRFS_QGROUP_RSV_DATA) return "data"; if (type == BTRFS_QGROUP_RSV_META_PERTRANS) return "meta_pertrans"; if (type == BTRFS_QGROUP_RSV_META_PREALLOC) return "meta_prealloc"; return NULL; } #endif static void qgroup_rsv_add(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *qgroup, u64 num_bytes, enum btrfs_qgroup_rsv_type type) { trace_qgroup_update_reserve(fs_info, qgroup, num_bytes, type); qgroup->rsv.values[type] += num_bytes; } static void qgroup_rsv_release(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *qgroup, u64 num_bytes, enum btrfs_qgroup_rsv_type type) { trace_qgroup_update_reserve(fs_info, qgroup, -(s64)num_bytes, type); if (qgroup->rsv.values[type] >= num_bytes) { qgroup->rsv.values[type] -= num_bytes; return; } #ifdef CONFIG_BTRFS_DEBUG WARN_RATELIMIT(1, "qgroup %llu %s reserved space underflow, have %llu to free %llu", qgroup->qgroupid, qgroup_rsv_type_str(type), qgroup->rsv.values[type], num_bytes); #endif qgroup->rsv.values[type] = 0; } static void qgroup_rsv_add_by_qgroup(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *dest, const struct btrfs_qgroup *src) { int i; for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) qgroup_rsv_add(fs_info, dest, src->rsv.values[i], i); } static void qgroup_rsv_release_by_qgroup(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *dest, const struct btrfs_qgroup *src) { int i; for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) qgroup_rsv_release(fs_info, dest, src->rsv.values[i], i); } static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq, int mod) { if (qg->old_refcnt < seq) qg->old_refcnt = seq; qg->old_refcnt += mod; } static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq, int mod) { if (qg->new_refcnt < seq) qg->new_refcnt = seq; qg->new_refcnt += mod; } static inline u64 btrfs_qgroup_get_old_refcnt(const struct btrfs_qgroup *qg, u64 seq) { if (qg->old_refcnt < seq) return 0; return qg->old_refcnt - seq; } static inline u64 btrfs_qgroup_get_new_refcnt(const struct btrfs_qgroup *qg, u64 seq) { if (qg->new_refcnt < seq) return 0; return qg->new_refcnt - seq; } static int qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid, int init_flags); static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info); /* must be called with qgroup_ioctl_lock held */ static struct btrfs_qgroup *find_qgroup_rb(const struct btrfs_fs_info *fs_info, u64 qgroupid) { struct rb_node *n = fs_info->qgroup_tree.rb_node; struct btrfs_qgroup *qgroup; while (n) { qgroup = rb_entry(n, struct btrfs_qgroup, node); if (qgroup->qgroupid < qgroupid) n = n->rb_left; else if (qgroup->qgroupid > qgroupid) n = n->rb_right; else return qgroup; } return NULL; } /* * 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 transferred 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) { p = &(*p)->rb_left; } else if (qgroup->qgroupid > qgroupid) { p = &(*p)->rb_right; } else { kfree(prealloc); return qgroup; } } qgroup = prealloc; qgroup->qgroupid = qgroupid; INIT_LIST_HEAD(&qgroup->groups); INIT_LIST_HEAD(&qgroup->members); INIT_LIST_HEAD(&qgroup->dirty); INIT_LIST_HEAD(&qgroup->iterator); INIT_LIST_HEAD(&qgroup->nested_iterator); rb_link_node(&qgroup->node, parent, p); rb_insert_color(&qgroup->node, &fs_info->qgroup_tree); return qgroup; } static void __del_qgroup_rb(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *qgroup) { struct btrfs_qgroup_list *list; list_del(&qgroup->dirty); while (!list_empty(&qgroup->groups)) { list = list_first_entry(&qgroup->groups, struct btrfs_qgroup_list, next_group); list_del(&list->next_group); list_del(&list->next_member); kfree(list); } while (!list_empty(&qgroup->members)) { list = list_first_entry(&qgroup->members, struct btrfs_qgroup_list, next_member); list_del(&list->next_group); list_del(&list->next_member); kfree(list); } } /* must be called with qgroup_lock held */ static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid) { struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid); if (!qgroup) return -ENOENT; rb_erase(&qgroup->node, &fs_info->qgroup_tree); __del_qgroup_rb(fs_info, qgroup); return 0; } /* * Add relation specified by two qgroups. * * Must be called with qgroup_lock held, the ownership of @prealloc is * transferred to this function and caller should not touch it anymore. * * Return: 0 on success * -ENOENT if one of the qgroups is NULL * <0 other errors */ static int __add_relation_rb(struct btrfs_qgroup_list *prealloc, struct btrfs_qgroup *member, struct btrfs_qgroup *parent) { if (!member || !parent) { kfree(prealloc); return -ENOENT; } prealloc->group = parent; prealloc->member = member; list_add_tail(&prealloc->next_group, &member->groups); list_add_tail(&prealloc->next_member, &parent->members); return 0; } /* * Add relation specified by two qgroup ids. * * Must be called with qgroup_lock held. * * Return: 0 on success * -ENOENT if one of the ids does not exist * <0 other errors */ static int add_relation_rb(struct btrfs_fs_info *fs_info, struct btrfs_qgroup_list *prealloc, u64 memberid, u64 parentid) { struct btrfs_qgroup *member; struct btrfs_qgroup *parent; member = find_qgroup_rb(fs_info, memberid); parent = find_qgroup_rb(fs_info, parentid); return __add_relation_rb(prealloc, member, parent); } /* Must be called with qgroup_lock held */ static int del_relation_rb(struct btrfs_fs_info *fs_info, u64 memberid, u64 parentid) { struct btrfs_qgroup *member; struct btrfs_qgroup *parent; struct btrfs_qgroup_list *list; member = find_qgroup_rb(fs_info, memberid); parent = find_qgroup_rb(fs_info, parentid); if (!member || !parent) return -ENOENT; list_for_each_entry(list, &member->groups, next_group) { if (list->group == parent) { list_del(&list->next_group); list_del(&list->next_member); kfree(list); return 0; } } return -ENOENT; } #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS int btrfs_verify_qgroup_counts(const struct btrfs_fs_info *fs_info, u64 qgroupid, u64 rfer, u64 excl) { struct btrfs_qgroup *qgroup; qgroup = find_qgroup_rb(fs_info, qgroupid); if (!qgroup) return -EINVAL; if (qgroup->rfer != rfer || qgroup->excl != excl) return -EINVAL; return 0; } #endif static void qgroup_mark_inconsistent(struct btrfs_fs_info *fs_info) { if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) return; fs_info->qgroup_flags |= (BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT | BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN | BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING); } static void qgroup_read_enable_gen(struct btrfs_fs_info *fs_info, struct extent_buffer *leaf, int slot, struct btrfs_qgroup_status_item *ptr) { ASSERT(btrfs_fs_incompat(fs_info, SIMPLE_QUOTA)); ASSERT(btrfs_item_size(leaf, slot) >= sizeof(*ptr)); fs_info->qgroup_enable_gen = btrfs_qgroup_status_enable_gen(leaf, ptr); } /* * The full config is read in one go, only called from open_ctree() * It doesn't use any locking, as at this point we're still single-threaded */ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info) { struct btrfs_key key; struct btrfs_key found_key; struct btrfs_root *quota_root = fs_info->quota_root; struct btrfs_path *path = NULL; struct extent_buffer *l; int slot; int ret = 0; u64 flags = 0; u64 rescan_progress = 0; if (!fs_info->quota_root) return 0; fs_info->qgroup_ulist = ulist_alloc(GFP_KERNEL); if (!fs_info->qgroup_ulist) { ret = -ENOMEM; goto out; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } ret = btrfs_sysfs_add_qgroups(fs_info); if (ret < 0) goto out; /* default this to quota off, in case no status key is found */ fs_info->qgroup_flags = 0; /* * pass 1: read status, all qgroup infos and limits */ key.objectid = 0; key.type = 0; key.offset = 0; ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1); if (ret) goto out; while (1) { struct btrfs_qgroup *qgroup; slot = path->slots[0]; l = path->nodes[0]; btrfs_item_key_to_cpu(l, &found_key, slot); if (found_key.type == BTRFS_QGROUP_STATUS_KEY) { struct btrfs_qgroup_status_item *ptr; ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item); if (btrfs_qgroup_status_version(l, ptr) != BTRFS_QGROUP_STATUS_VERSION) { btrfs_err(fs_info, "old qgroup version, quota disabled"); goto out; } fs_info->qgroup_flags = btrfs_qgroup_status_flags(l, ptr); if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE) { qgroup_read_enable_gen(fs_info, l, slot, ptr); } else if (btrfs_qgroup_status_generation(l, ptr) != fs_info->generation) { qgroup_mark_inconsistent(fs_info); btrfs_err(fs_info, "qgroup generation mismatch, marked as inconsistent"); } rescan_progress = btrfs_qgroup_status_rescan(l, ptr); goto next1; } if (found_key.type != BTRFS_QGROUP_INFO_KEY && found_key.type != BTRFS_QGROUP_LIMIT_KEY) goto next1; qgroup = find_qgroup_rb(fs_info, found_key.offset); if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) || (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) { btrfs_err(fs_info, "inconsistent qgroup config"); qgroup_mark_inconsistent(fs_info); } if (!qgroup) { struct btrfs_qgroup *prealloc; struct btrfs_root *tree_root = fs_info->tree_root; prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL); if (!prealloc) { ret = -ENOMEM; goto out; } qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset); /* * If a qgroup exists for a subvolume ID, it is possible * that subvolume has been deleted, in which case * re-using that ID would lead to incorrect accounting. * * Ensure that we skip any such subvol ids. * * We don't need to lock because this is only called * during mount before we start doing things like creating * subvolumes. */ if (is_fstree(qgroup->qgroupid) && qgroup->qgroupid > tree_root->free_objectid) /* * Don't need to check against BTRFS_LAST_FREE_OBJECTID, * as it will get checked on the next call to * btrfs_get_free_objectid. */ tree_root->free_objectid = qgroup->qgroupid + 1; } ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); if (ret < 0) goto out; switch (found_key.type) { case BTRFS_QGROUP_INFO_KEY: { struct btrfs_qgroup_info_item *ptr; ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item); qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr); qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr); qgroup->excl = btrfs_qgroup_info_excl(l, ptr); qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr); /* generation currently unused */ break; } case BTRFS_QGROUP_LIMIT_KEY: { struct btrfs_qgroup_limit_item *ptr; ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item); qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr); qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr); qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr); qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr); qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr); break; } } next1: ret = btrfs_next_item(quota_root, path); if (ret < 0) goto out; if (ret) break; } btrfs_release_path(path); /* * pass 2: read all qgroup relations */ key.objectid = 0; key.type = BTRFS_QGROUP_RELATION_KEY; key.offset = 0; ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0); if (ret) goto out; while (1) { struct btrfs_qgroup_list *list = NULL; slot = path->slots[0]; l = path->nodes[0]; btrfs_item_key_to_cpu(l, &found_key, slot); if (found_key.type != BTRFS_QGROUP_RELATION_KEY) goto next2; if (found_key.objectid > found_key.offset) { /* parent <- member, not needed to build config */ /* FIXME should we omit the key completely? */ goto next2; } list = kzalloc(sizeof(*list), GFP_KERNEL); if (!list) { ret = -ENOMEM; goto out; } ret = add_relation_rb(fs_info, list, found_key.objectid, found_key.offset); list = NULL; if (ret == -ENOENT) { btrfs_warn(fs_info, "orphan qgroup relation 0x%llx->0x%llx", found_key.objectid, found_key.offset); ret = 0; /* ignore the error */ } if (ret) goto out; next2: ret = btrfs_next_item(quota_root, path); if (ret < 0) goto out; if (ret) break; } out: btrfs_free_path(path); fs_info->qgroup_flags |= flags; if (ret >= 0) { if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON) set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags); if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ret = qgroup_rescan_init(fs_info, rescan_progress, 0); } else { ulist_free(fs_info->qgroup_ulist); fs_info->qgroup_ulist = NULL; fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN; btrfs_sysfs_del_qgroups(fs_info); } return ret < 0 ? ret : 0; } /* * Called in close_ctree() when quota is still enabled. This verifies we don't * leak some reserved space. * * Return false if no reserved space is left. * Return true if some reserved space is leaked. */ bool btrfs_check_quota_leak(const struct btrfs_fs_info *fs_info) { struct rb_node *node; bool ret = false; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) return ret; /* * Since we're unmounting, there is no race and no need to grab qgroup * lock. And here we don't go post-order to provide a more user * friendly sorted result. */ for (node = rb_first(&fs_info->qgroup_tree); node; node = rb_next(node)) { struct btrfs_qgroup *qgroup; int i; qgroup = rb_entry(node, struct btrfs_qgroup, node); for (i = 0; i < BTRFS_QGROUP_RSV_LAST; i++) { if (qgroup->rsv.values[i]) { ret = true; btrfs_warn(fs_info, "qgroup %hu/%llu has unreleased space, type %d rsv %llu", btrfs_qgroup_level(qgroup->qgroupid), btrfs_qgroup_subvolid(qgroup->qgroupid), i, qgroup->rsv.values[i]); } } } return ret; } /* * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(), * first two are in single-threaded paths.And for the third one, we have set * quota_root to be null with qgroup_lock held before, so it is safe to clean * up the in-memory structures without qgroup_lock held. */ void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info) { struct rb_node *n; struct btrfs_qgroup *qgroup; while ((n = rb_first(&fs_info->qgroup_tree))) { qgroup = rb_entry(n, struct btrfs_qgroup, node); rb_erase(n, &fs_info->qgroup_tree); __del_qgroup_rb(fs_info, qgroup); btrfs_sysfs_del_one_qgroup(fs_info, qgroup); kfree(qgroup); } /* * We call btrfs_free_qgroup_config() when unmounting * filesystem and disabling quota, so we set qgroup_ulist * to be null here to avoid double free. */ ulist_free(fs_info->qgroup_ulist); fs_info->qgroup_ulist = NULL; btrfs_sysfs_del_qgroups(fs_info); } static int add_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src, u64 dst) { int ret; struct btrfs_root *quota_root = trans->fs_info->quota_root; struct btrfs_path *path; struct btrfs_key key; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = src; key.type = BTRFS_QGROUP_RELATION_KEY; key.offset = dst; ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0); btrfs_mark_buffer_dirty(trans, path->nodes[0]); btrfs_free_path(path); return ret; } static int del_qgroup_relation_item(struct btrfs_trans_handle *trans, u64 src, u64 dst) { int ret; struct btrfs_root *quota_root = trans->fs_info->quota_root; struct btrfs_path *path; struct btrfs_key key; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = src; key.type = BTRFS_QGROUP_RELATION_KEY; key.offset = dst; ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, quota_root, path); out: btrfs_free_path(path); return ret; } static int add_qgroup_item(struct btrfs_trans_handle *trans, struct btrfs_root *quota_root, u64 qgroupid) { int ret; struct btrfs_path *path; struct btrfs_qgroup_info_item *qgroup_info; struct btrfs_qgroup_limit_item *qgroup_limit; struct extent_buffer *leaf; struct btrfs_key key; if (btrfs_is_testing(quota_root->fs_info)) return 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = 0; key.type = BTRFS_QGROUP_INFO_KEY; key.offset = qgroupid; /* * Avoid a transaction abort by catching -EEXIST here. In that * case, we proceed by re-initializing the existing structure * on disk. */ ret = btrfs_insert_empty_item(trans, quota_root, path, &key, sizeof(*qgroup_info)); if (ret && ret != -EEXIST) goto out; leaf = path->nodes[0]; qgroup_info = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_qgroup_info_item); btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid); btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0); btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0); btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0); btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0); btrfs_mark_buffer_dirty(trans, leaf); btrfs_release_path(path); key.type = BTRFS_QGROUP_LIMIT_KEY; ret = btrfs_insert_empty_item(trans, quota_root, path, &key, sizeof(*qgroup_limit)); if (ret && ret != -EEXIST) goto out; leaf = path->nodes[0]; qgroup_limit = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_qgroup_limit_item); btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0); btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0); btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0); btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0); btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0); btrfs_mark_buffer_dirty(trans, leaf); ret = 0; out: btrfs_free_path(path); return ret; } static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid) { int ret; struct btrfs_root *quota_root = trans->fs_info->quota_root; struct btrfs_path *path; struct btrfs_key key; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = 0; key.type = BTRFS_QGROUP_INFO_KEY; key.offset = qgroupid; ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, quota_root, path); if (ret) goto out; btrfs_release_path(path); key.type = BTRFS_QGROUP_LIMIT_KEY; ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, quota_root, path); out: btrfs_free_path(path); return ret; } static int update_qgroup_limit_item(struct btrfs_trans_handle *trans, struct btrfs_qgroup *qgroup) { struct btrfs_root *quota_root = trans->fs_info->quota_root; struct btrfs_path *path; struct btrfs_key key; struct extent_buffer *l; struct btrfs_qgroup_limit_item *qgroup_limit; int ret; int slot; key.objectid = 0; key.type = BTRFS_QGROUP_LIMIT_KEY; key.offset = qgroup->qgroupid; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1); if (ret > 0) ret = -ENOENT; if (ret) goto out; l = path->nodes[0]; slot = path->slots[0]; qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item); btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags); btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer); btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl); btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer); btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl); btrfs_mark_buffer_dirty(trans, l); out: btrfs_free_path(path); return ret; } static int update_qgroup_info_item(struct btrfs_trans_handle *trans, struct btrfs_qgroup *qgroup) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *quota_root = fs_info->quota_root; struct btrfs_path *path; struct btrfs_key key; struct extent_buffer *l; struct btrfs_qgroup_info_item *qgroup_info; int ret; int slot; if (btrfs_is_testing(fs_info)) return 0; key.objectid = 0; key.type = BTRFS_QGROUP_INFO_KEY; key.offset = qgroup->qgroupid; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1); if (ret > 0) ret = -ENOENT; if (ret) goto out; l = path->nodes[0]; slot = path->slots[0]; qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item); btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid); btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer); btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr); btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl); btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr); btrfs_mark_buffer_dirty(trans, l); out: btrfs_free_path(path); return ret; } static int update_qgroup_status_item(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *quota_root = fs_info->quota_root; struct btrfs_path *path; struct btrfs_key key; struct extent_buffer *l; struct btrfs_qgroup_status_item *ptr; int ret; int slot; key.objectid = 0; key.type = BTRFS_QGROUP_STATUS_KEY; key.offset = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1); if (ret > 0) ret = -ENOENT; if (ret) goto out; l = path->nodes[0]; slot = path->slots[0]; ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item); btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAGS_MASK); btrfs_set_qgroup_status_generation(l, ptr, trans->transid); btrfs_set_qgroup_status_rescan(l, ptr, fs_info->qgroup_rescan_progress.objectid); btrfs_mark_buffer_dirty(trans, l); out: btrfs_free_path(path); return ret; } /* * called with qgroup_lock held */ static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans, struct btrfs_root *root) { struct btrfs_path *path; struct btrfs_key key; struct extent_buffer *leaf = NULL; int ret; int nr = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = 0; key.offset = 0; key.type = 0; while (1) { ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; leaf = path->nodes[0]; nr = btrfs_header_nritems(leaf); if (!nr) break; /* * delete the leaf one by one * since the whole tree is going * to be deleted. */ path->slots[0] = 0; ret = btrfs_del_items(trans, root, path, 0, nr); if (ret) goto out; btrfs_release_path(path); } ret = 0; out: btrfs_free_path(path); return ret; } int btrfs_quota_enable(struct btrfs_fs_info *fs_info, struct btrfs_ioctl_quota_ctl_args *quota_ctl_args) { struct btrfs_root *quota_root; struct btrfs_root *tree_root = fs_info->tree_root; struct btrfs_path *path = NULL; struct btrfs_qgroup_status_item *ptr; struct extent_buffer *leaf; 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; const bool simple = (quota_ctl_args->cmd == BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA); int ret = 0; int slot; /* * We need to have subvol_sem write locked, to prevent races between * concurrent tasks trying to enable quotas, because we will unlock * and relock qgroup_ioctl_lock before setting fs_info->quota_root * and before setting BTRFS_FS_QUOTA_ENABLED. */ lockdep_assert_held_write(&fs_info->subvol_sem); if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { btrfs_err(fs_info, "qgroups are currently unsupported in extent tree v2"); return -EINVAL; } mutex_lock(&fs_info->qgroup_ioctl_lock); if (fs_info->quota_root) goto out; ulist = ulist_alloc(GFP_KERNEL); if (!ulist) { ret = -ENOMEM; goto out; } ret = btrfs_sysfs_add_qgroups(fs_info); if (ret < 0) goto out; /* * Unlock qgroup_ioctl_lock before starting the transaction. This is to * avoid lock acquisition inversion problems (reported by lockdep) between * qgroup_ioctl_lock and the vfs freeze semaphores, acquired when we * start a transaction. * After we started the transaction lock qgroup_ioctl_lock again and * check if someone else created the quota root in the meanwhile. If so, * just return success and release the transaction handle. * * Also we don't need to worry about someone else calling * btrfs_sysfs_add_qgroups() after we unlock and getting an error because * that function returns 0 (success) when the sysfs entries already exist. */ mutex_unlock(&fs_info->qgroup_ioctl_lock); /* * 1 for quota root item * 1 for BTRFS_QGROUP_STATUS item * * Yet we also need 2*n items for a QGROUP_INFO/QGROUP_LIMIT items * per subvolume. However those are not currently reserved since it * would be a lot of overkill. */ trans = btrfs_start_transaction(tree_root, 2); mutex_lock(&fs_info->qgroup_ioctl_lock); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } if (fs_info->quota_root) goto out; fs_info->qgroup_ulist = ulist; ulist = NULL; /* * initially create the quota tree */ quota_root = btrfs_create_tree(trans, BTRFS_QUOTA_TREE_OBJECTID); if (IS_ERR(quota_root)) { ret = PTR_ERR(quota_root); btrfs_abort_transaction(trans, ret); goto out; } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; btrfs_abort_transaction(trans, ret); goto out_free_root; } key.objectid = 0; key.type = BTRFS_QGROUP_STATUS_KEY; key.offset = 0; ret = btrfs_insert_empty_item(trans, quota_root, path, &key, sizeof(*ptr)); if (ret) { btrfs_abort_transaction(trans, ret); goto out_free_path; } leaf = path->nodes[0]; ptr = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_qgroup_status_item); btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid); btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION); fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON; if (simple) { fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE; btrfs_set_qgroup_status_enable_gen(leaf, ptr, trans->transid); } else { fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT; } btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAGS_MASK); btrfs_set_qgroup_status_rescan(leaf, ptr, 0); btrfs_mark_buffer_dirty(trans, leaf); key.objectid = 0; key.type = BTRFS_ROOT_REF_KEY; key.offset = 0; btrfs_release_path(path); ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0); if (ret > 0) goto out_add_root; if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out_free_path; } while (1) { slot = path->slots[0]; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, slot); if (found_key.type == BTRFS_ROOT_REF_KEY) { /* 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) { btrfs_abort_transaction(trans, ret); goto out_free_path; } 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); goto out_free_path; } ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out_free_path; } ret = btrfs_search_slot_for_read(tree_root, &found_key, path, 1, 0); if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out_free_path; } if (ret > 0) { /* * Shouldn't happen, but in case it does we * don't need to do the btrfs_next_item, just * continue. */ continue; } } ret = btrfs_next_item(tree_root, path); if (ret < 0) { btrfs_abort_transaction(trans, ret); goto out_free_path; } if (ret) break; } out_add_root: btrfs_release_path(path); ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID); if (ret) { btrfs_abort_transaction(trans, ret); goto out_free_path; } 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); goto out_free_path; } fs_info->qgroup_enable_gen = trans->transid; mutex_unlock(&fs_info->qgroup_ioctl_lock); /* * Commit the transaction while not holding qgroup_ioctl_lock, to avoid * a deadlock with tasks concurrently doing other qgroup operations, such * adding/removing qgroups or adding/deleting qgroup relations for example, * because all qgroup operations first start or join a transaction and then * lock the qgroup_ioctl_lock mutex. * We are safe from a concurrent task trying to enable quotas, by calling * this function, since we are serialized by fs_info->subvol_sem. */ ret = btrfs_commit_transaction(trans); trans = NULL; mutex_lock(&fs_info->qgroup_ioctl_lock); if (ret) goto out_free_path; /* * Set quota enabled flag after committing the transaction, to avoid * deadlocks on fs_info->qgroup_ioctl_lock with concurrent snapshot * creation. */ spin_lock(&fs_info->qgroup_lock); fs_info->quota_root = quota_root; set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags); if (simple) btrfs_set_fs_incompat(fs_info, SIMPLE_QUOTA); spin_unlock(&fs_info->qgroup_lock); /* Skip rescan for simple qgroups. */ if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) goto out_free_path; ret = qgroup_rescan_init(fs_info, 0, 1); if (!ret) { qgroup_rescan_zero_tracking(fs_info); fs_info->qgroup_rescan_running = true; btrfs_queue_work(fs_info->qgroup_rescan_workers, &fs_info->qgroup_rescan_work); } else { /* * We have set both BTRFS_FS_QUOTA_ENABLED and * BTRFS_QGROUP_STATUS_FLAG_ON, so we can only fail with * -EINPROGRESS. That can happen because someone started the * rescan worker by calling quota rescan ioctl before we * attempted to initialize the rescan worker. Failure due to * quotas disabled in the meanwhile is not possible, because * we are holding a write lock on fs_info->subvol_sem, which * is also acquired when disabling quotas. * Ignore such error, and any other error would need to undo * everything we did in the transaction we just committed. */ ASSERT(ret == -EINPROGRESS); ret = 0; } out_free_path: btrfs_free_path(path); out_free_root: if (ret) btrfs_put_root(quota_root); out: if (ret) { ulist_free(fs_info->qgroup_ulist); fs_info->qgroup_ulist = NULL; btrfs_sysfs_del_qgroups(fs_info); } mutex_unlock(&fs_info->qgroup_ioctl_lock); if (ret && trans) btrfs_end_transaction(trans); else if (trans) ret = btrfs_end_transaction(trans); ulist_free(ulist); kfree(prealloc); return ret; } /* * It is possible to have outstanding ordered extents which reserved bytes * before we disabled. We need to fully flush delalloc, ordered extents, and a * commit to ensure that we don't leak such reservations, only to have them * come back if we re-enable. * * - enable simple quotas * - reserve space * - release it, store rsv_bytes in OE * - disable quotas * - enable simple quotas (qgroup rsv are all 0) * - OE finishes * - run delayed refs * - free rsv_bytes, resulting in miscounting or even underflow */ static int flush_reservations(struct btrfs_fs_info *fs_info) { int ret; ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false); if (ret) return ret; btrfs_wait_ordered_roots(fs_info, U64_MAX, NULL); return btrfs_commit_current_transaction(fs_info->tree_root); } int btrfs_quota_disable(struct btrfs_fs_info *fs_info) { struct btrfs_root *quota_root = NULL; struct btrfs_trans_handle *trans = NULL; int ret = 0; /* * We need to have subvol_sem write locked to prevent races with * snapshot creation. */ lockdep_assert_held_write(&fs_info->subvol_sem); /* * Relocation will mess with backrefs, so make sure we have the * cleaner_mutex held to protect us from relocate. */ lockdep_assert_held(&fs_info->cleaner_mutex); mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) goto out; /* * Unlock the qgroup_ioctl_lock mutex before waiting for the rescan worker to * complete. Otherwise we can deadlock because btrfs_remove_qgroup() needs * to lock that mutex while holding a transaction handle and the rescan * worker needs to commit a transaction. */ mutex_unlock(&fs_info->qgroup_ioctl_lock); /* * Request qgroup rescan worker to complete and wait for it. This wait * must be done before transaction start for quota disable since it may * deadlock with transaction by the qgroup rescan worker. */ clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags); btrfs_qgroup_wait_for_completion(fs_info, false); /* * We have nothing held here and no trans handle, just return the error * if there is one. */ ret = flush_reservations(fs_info); if (ret) return ret; /* * 1 For the root item * * We should also reserve enough items for the quota tree deletion in * btrfs_clean_quota_tree but this is not done. * * Also, we must always start a transaction without holding the mutex * qgroup_ioctl_lock, see btrfs_quota_enable(). */ trans = btrfs_start_transaction(fs_info->tree_root, 1); mutex_lock(&fs_info->qgroup_ioctl_lock); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags); goto out; } if (!fs_info->quota_root) goto out; spin_lock(&fs_info->qgroup_lock); quota_root = fs_info->quota_root; fs_info->quota_root = NULL; fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON; fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_SIMPLE_MODE; fs_info->qgroup_drop_subtree_thres = BTRFS_QGROUP_DROP_SUBTREE_THRES_DEFAULT; spin_unlock(&fs_info->qgroup_lock); btrfs_free_qgroup_config(fs_info); ret = btrfs_clean_quota_tree(trans, quota_root); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } ret = btrfs_del_root(trans, "a_root->root_key); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } spin_lock(&fs_info->trans_lock); list_del("a_root->dirty_list); spin_unlock(&fs_info->trans_lock); btrfs_tree_lock(quota_root->node); btrfs_clear_buffer_dirty(trans, quota_root->node); btrfs_tree_unlock(quota_root->node); ret = btrfs_free_tree_block(trans, btrfs_root_id(quota_root), quota_root->node, 0, 1); if (ret < 0) btrfs_abort_transaction(trans, ret); out: btrfs_put_root(quota_root); mutex_unlock(&fs_info->qgroup_ioctl_lock); if (ret && trans) btrfs_end_transaction(trans); else if (trans) ret = btrfs_commit_transaction(trans); return ret; } static void qgroup_dirty(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *qgroup) { if (list_empty(&qgroup->dirty)) list_add(&qgroup->dirty, &fs_info->dirty_qgroups); } static void qgroup_iterator_add(struct list_head *head, struct btrfs_qgroup *qgroup) { if (!list_empty(&qgroup->iterator)) return; list_add_tail(&qgroup->iterator, head); } static void qgroup_iterator_clean(struct list_head *head) { while (!list_empty(head)) { struct btrfs_qgroup *qgroup; qgroup = list_first_entry(head, struct btrfs_qgroup, iterator); list_del_init(&qgroup->iterator); } } /* * The easy accounting, we're updating qgroup relationship whose child qgroup * only has exclusive extents. * * In this case, all exclusive extents will also be exclusive for parent, so * excl/rfer just get added/removed. * * So is qgroup reservation space, which should also be added/removed to * parent. * Or when child tries to release reservation space, parent will underflow its * reservation (for relationship adding case). * * Caller should hold fs_info->qgroup_lock. */ static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info, u64 ref_root, struct btrfs_qgroup *src, int sign) { struct btrfs_qgroup *qgroup; struct btrfs_qgroup *cur; LIST_HEAD(qgroup_list); u64 num_bytes = src->excl; int ret = 0; qgroup = find_qgroup_rb(fs_info, ref_root); if (!qgroup) goto out; qgroup_iterator_add(&qgroup_list, qgroup); list_for_each_entry(cur, &qgroup_list, iterator) { struct btrfs_qgroup_list *glist; qgroup->rfer += sign * num_bytes; qgroup->rfer_cmpr += sign * num_bytes; WARN_ON(sign < 0 && qgroup->excl < num_bytes); qgroup->excl += sign * num_bytes; qgroup->excl_cmpr += sign * num_bytes; if (sign > 0) qgroup_rsv_add_by_qgroup(fs_info, qgroup, src); else qgroup_rsv_release_by_qgroup(fs_info, qgroup, src); qgroup_dirty(fs_info, qgroup); /* Append parent qgroups to @qgroup_list. */ list_for_each_entry(glist, &qgroup->groups, next_group) qgroup_iterator_add(&qgroup_list, glist->group); } ret = 0; out: qgroup_iterator_clean(&qgroup_list); return ret; } /* * Quick path for updating qgroup with only excl refs. * * In that case, just update all parent will be enough. * Or we needs to do a full rescan. * Caller should also hold fs_info->qgroup_lock. * * Return 0 for quick update, return >0 for need to full rescan * and mark INCONSISTENT flag. * Return < 0 for other error. */ static int quick_update_accounting(struct btrfs_fs_info *fs_info, u64 src, u64 dst, int sign) { struct btrfs_qgroup *qgroup; int ret = 1; qgroup = find_qgroup_rb(fs_info, src); if (!qgroup) goto out; if (qgroup->excl == qgroup->rfer) { ret = __qgroup_excl_accounting(fs_info, dst, qgroup, sign); if (ret < 0) goto out; ret = 0; } out: if (ret) fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT; return ret; } /* * Add relation between @src and @dst qgroup. The @prealloc is allocated by the * callers and transferred here (either used or freed on error). */ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst, struct btrfs_qgroup_list *prealloc) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_qgroup *parent; struct btrfs_qgroup *member; struct btrfs_qgroup_list *list; int ret = 0; ASSERT(prealloc); /* Check the level of src and dst first */ if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst)) return -EINVAL; mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) { ret = -ENOTCONN; goto out; } member = find_qgroup_rb(fs_info, src); parent = find_qgroup_rb(fs_info, dst); if (!member || !parent) { ret = -EINVAL; goto out; } /* check if such qgroup relation exist firstly */ list_for_each_entry(list, &member->groups, next_group) { if (list->group == parent) { ret = -EEXIST; goto out; } } ret = add_qgroup_relation_item(trans, src, dst); if (ret) goto out; ret = add_qgroup_relation_item(trans, dst, src); if (ret) { del_qgroup_relation_item(trans, src, dst); goto out; } spin_lock(&fs_info->qgroup_lock); ret = __add_relation_rb(prealloc, member, parent); prealloc = NULL; if (ret < 0) { spin_unlock(&fs_info->qgroup_lock); goto out; } ret = quick_update_accounting(fs_info, src, dst, 1); spin_unlock(&fs_info->qgroup_lock); out: kfree(prealloc); mutex_unlock(&fs_info->qgroup_ioctl_lock); return ret; } static int __del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_qgroup *parent; struct btrfs_qgroup *member; struct btrfs_qgroup_list *list; bool found = false; int ret = 0; int ret2; if (!fs_info->quota_root) { ret = -ENOTCONN; goto out; } member = find_qgroup_rb(fs_info, src); parent = find_qgroup_rb(fs_info, dst); /* * The parent/member pair doesn't exist, then try to delete the dead * relation items only. */ if (!member || !parent) goto delete_item; /* check if such qgroup relation exist firstly */ list_for_each_entry(list, &member->groups, next_group) { if (list->group == parent) { found = true; break; } } delete_item: ret = del_qgroup_relation_item(trans, src, dst); if (ret < 0 && ret != -ENOENT) goto out; ret2 = del_qgroup_relation_item(trans, dst, src); if (ret2 < 0 && ret2 != -ENOENT) goto out; /* At least one deletion succeeded, return 0 */ if (!ret || !ret2) ret = 0; if (found) { spin_lock(&fs_info->qgroup_lock); del_relation_rb(fs_info, src, dst); ret = quick_update_accounting(fs_info, src, dst, -1); spin_unlock(&fs_info->qgroup_lock); } out: return ret; } int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src, u64 dst) { struct btrfs_fs_info *fs_info = trans->fs_info; int ret = 0; mutex_lock(&fs_info->qgroup_ioctl_lock); ret = __del_qgroup_relation(trans, src, dst); mutex_unlock(&fs_info->qgroup_ioctl_lock); return ret; } 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; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) return 0; mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) { ret = -ENOTCONN; goto out; } quota_root = fs_info->quota_root; qgroup = find_qgroup_rb(fs_info, qgroupid); if (qgroup) { ret = -EEXIST; 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, prealloc, qgroupid); spin_unlock(&fs_info->qgroup_lock); prealloc = NULL; ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); out: mutex_unlock(&fs_info->qgroup_ioctl_lock); kfree(prealloc); return ret; } /* * Return 0 if we can not delete the qgroup (not empty or has children etc). * Return >0 if we can delete the qgroup. * Return <0 for other errors during tree search. */ static int can_delete_qgroup(struct btrfs_fs_info *fs_info, struct btrfs_qgroup *qgroup) { struct btrfs_key key; struct btrfs_path *path; int ret; /* * Squota would never be inconsistent, but there can still be case * where a dropped subvolume still has qgroup numbers, and squota * relies on such qgroup for future accounting. * * So for squota, do not allow dropping any non-zero qgroup. */ if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE && (qgroup->rfer || qgroup->excl || qgroup->excl_cmpr || qgroup->rfer_cmpr)) return 0; /* For higher level qgroup, we can only delete it if it has no child. */ if (btrfs_qgroup_level(qgroup->qgroupid)) { if (!list_empty(&qgroup->members)) return 0; return 1; } /* * For level-0 qgroups, we can only delete it if it has no subvolume * for it. * This means even a subvolume is unlinked but not yet fully dropped, * we can not delete the qgroup. */ key.objectid = qgroup->qgroupid; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = -1ULL; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_find_root(fs_info->tree_root, &key, path, NULL, NULL); btrfs_free_path(path); /* * The @ret from btrfs_find_root() exactly matches our definition for * the return value, thus can be returned directly. */ return ret; } int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_qgroup *qgroup; struct btrfs_qgroup_list *list; int ret = 0; mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) { ret = -ENOTCONN; goto out; } qgroup = find_qgroup_rb(fs_info, qgroupid); if (!qgroup) { ret = -ENOENT; goto out; } ret = can_delete_qgroup(fs_info, qgroup); if (ret < 0) goto out; if (ret == 0) { ret = -EBUSY; goto out; } /* Check if there are no children of this qgroup */ if (!list_empty(&qgroup->members)) { ret = -EBUSY; goto out; } ret = del_qgroup_item(trans, qgroupid); if (ret && ret != -ENOENT) goto out; while (!list_empty(&qgroup->groups)) { list = list_first_entry(&qgroup->groups, struct btrfs_qgroup_list, next_group); ret = __del_qgroup_relation(trans, qgroupid, list->group->qgroupid); if (ret) goto out; } spin_lock(&fs_info->qgroup_lock); /* * Warn on reserved space. The subvolume should has no child nor * corresponding subvolume. * Thus its reserved space should all be zero, no matter if qgroup * is consistent or the mode. */ WARN_ON(qgroup->rsv.values[BTRFS_QGROUP_RSV_DATA] || qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC] || qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS]); /* * The same for rfer/excl numbers, but that's only if our qgroup is * consistent and if it's in regular qgroup mode. * For simple mode it's not as accurate thus we can hit non-zero values * very frequently. */ if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL && !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT)) { if (WARN_ON(qgroup->rfer || qgroup->excl || qgroup->rfer_cmpr || qgroup->excl_cmpr)) { btrfs_warn_rl(fs_info, "to be deleted qgroup %u/%llu has non-zero numbers, rfer %llu rfer_cmpr %llu excl %llu excl_cmpr %llu", btrfs_qgroup_level(qgroup->qgroupid), btrfs_qgroup_subvolid(qgroup->qgroupid), qgroup->rfer, qgroup->rfer_cmpr, qgroup->excl, qgroup->excl_cmpr); qgroup_mark_inconsistent(fs_info); } } del_qgroup_rb(fs_info, qgroupid); spin_unlock(&fs_info->qgroup_lock); /* * Remove the qgroup from sysfs now without holding the qgroup_lock * spinlock, since the sysfs_remove_group() function needs to take * the mutex kernfs_mutex through kernfs_remove_by_name_ns(). */ btrfs_sysfs_del_one_qgroup(fs_info, qgroup); kfree(qgroup); out: mutex_unlock(&fs_info->qgroup_ioctl_lock); return ret; } int btrfs_qgroup_cleanup_dropped_subvolume(struct btrfs_fs_info *fs_info, u64 subvolid) { struct btrfs_trans_handle *trans; int ret; if (!is_fstree(subvolid) || !btrfs_qgroup_enabled(fs_info) || !fs_info->quota_root) return 0; /* * Commit current transaction to make sure all the rfer/excl numbers * get updated. */ trans = btrfs_start_transaction(fs_info->quota_root, 0); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_commit_transaction(trans); if (ret < 0) return ret; /* Start new trans to delete the qgroup info and limit items. */ trans = btrfs_start_transaction(fs_info->quota_root, 2); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_remove_qgroup(trans, subvolid); btrfs_end_transaction(trans); /* * It's squota and the subvolume still has numbers needed for future * accounting, in this case we can not delete it. Just skip it. */ if (ret == -EBUSY) ret = 0; return ret; } int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid, struct btrfs_qgroup_limit *limit) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_qgroup *qgroup; int ret = 0; /* Sometimes we would want to clear the limit on this qgroup. * To meet this requirement, we treat the -1 as a special value * which tell kernel to clear the limit on this qgroup. */ const u64 CLEAR_VALUE = -1; mutex_lock(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) { ret = -ENOTCONN; goto out; } qgroup = find_qgroup_rb(fs_info, qgroupid); if (!qgroup) { ret = -ENOENT; goto out; } spin_lock(&fs_info->qgroup_lock); if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER) { if (limit->max_rfer == CLEAR_VALUE) { qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER; limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER; qgroup->max_rfer = 0; } else { qgroup->max_rfer = limit->max_rfer; } } if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) { if (limit->max_excl == CLEAR_VALUE) { qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL; limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL; qgroup->max_excl = 0; } else { qgroup->max_excl = limit->max_excl; } } if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) { if (limit->rsv_rfer == CLEAR_VALUE) { qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER; limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER; qgroup->rsv_rfer = 0; } else { qgroup->rsv_rfer = limit->rsv_rfer; } } if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) { if (limit->rsv_excl == CLEAR_VALUE) { qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL; limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL; qgroup->rsv_excl = 0; } else { qgroup->rsv_excl = limit->rsv_excl; } } qgroup->lim_flags |= limit->flags; spin_unlock(&fs_info->qgroup_lock); ret = update_qgroup_limit_item(trans, qgroup); if (ret) { qgroup_mark_inconsistent(fs_info); btrfs_info(fs_info, "unable to update quota limit for %llu", qgroupid); } out: mutex_unlock(&fs_info->qgroup_ioctl_lock); return ret; } /* * Inform qgroup to trace one dirty extent, its info is recorded in @record. * So qgroup can account it at transaction committing time. * * No lock version, caller must acquire delayed ref lock and allocated memory, * then call btrfs_qgroup_trace_extent_post() after exiting lock context. * * Return 0 for success insert * Return >0 for existing record, caller can free @record safely. * Return <0 for insertion failure, caller can free @record safely. */ int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_root *delayed_refs, struct btrfs_qgroup_extent_record *record) { struct btrfs_qgroup_extent_record *existing, *ret; const unsigned long index = (record->bytenr >> fs_info->sectorsize_bits); if (!btrfs_qgroup_full_accounting(fs_info)) return 1; #if BITS_PER_LONG == 32 if (record->bytenr >= MAX_LFS_FILESIZE) { btrfs_err_rl(fs_info, "qgroup record for extent at %llu is beyond 32bit page cache and xarray index limit", record->bytenr); btrfs_err_32bit_limit(fs_info); return -EOVERFLOW; } #endif lockdep_assert_held(&delayed_refs->lock); trace_btrfs_qgroup_trace_extent(fs_info, record); xa_lock(&delayed_refs->dirty_extents); existing = xa_load(&delayed_refs->dirty_extents, index); if (existing) { if (record->data_rsv && !existing->data_rsv) { existing->data_rsv = record->data_rsv; existing->data_rsv_refroot = record->data_rsv_refroot; } xa_unlock(&delayed_refs->dirty_extents); return 1; } ret = __xa_store(&delayed_refs->dirty_extents, index, record, GFP_ATOMIC); xa_unlock(&delayed_refs->dirty_extents); if (xa_is_err(ret)) { qgroup_mark_inconsistent(fs_info); return xa_err(ret); } return 0; } /* * Post handler after qgroup_trace_extent_nolock(). * * NOTE: Current qgroup does the expensive backref walk at transaction * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming * new transaction. * This is designed to allow btrfs_find_all_roots() to get correct new_roots * result. * * However for old_roots there is no need to do backref walk at that time, * since we search commit roots to walk backref and result will always be * correct. * * Due to the nature of no lock version, we can't do backref there. * So we must call btrfs_qgroup_trace_extent_post() after exiting * spinlock context. * * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result * using current root, then we can move all expensive backref walk out of * transaction committing, but not now as qgroup accounting will be wrong again. */ int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans, struct btrfs_qgroup_extent_record *qrecord) { struct btrfs_backref_walk_ctx ctx = { 0 }; int ret; if (!btrfs_qgroup_full_accounting(trans->fs_info)) return 0; /* * We are always called in a context where we are already holding a * transaction handle. Often we are called when adding a data delayed * reference from btrfs_truncate_inode_items() (truncating or unlinking), * in which case we will be holding a write lock on extent buffer from a * subvolume tree. In this case we can't allow btrfs_find_all_roots() to * acquire fs_info->commit_root_sem, because that is a higher level lock * that must be acquired before locking any extent buffers. * * So we want btrfs_find_all_roots() to not acquire the commit_root_sem * but we can't pass it a non-NULL transaction handle, because otherwise * it would not use commit roots and would lock extent buffers, causing * a deadlock if it ends up trying to read lock the same extent buffer * that was previously write locked at btrfs_truncate_inode_items(). * * So pass a NULL transaction handle to btrfs_find_all_roots() and * explicitly tell it to not acquire the commit_root_sem - if we are * holding a transaction handle we don't need its protection. */ ASSERT(trans != NULL); if (trans->fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING) return 0; ctx.bytenr = qrecord->bytenr; ctx.fs_info = trans->fs_info; ret = btrfs_find_all_roots(&ctx, true); if (ret < 0) { qgroup_mark_inconsistent(trans->fs_info); btrfs_warn(trans->fs_info, "error accounting new delayed refs extent (err code: %d), quota inconsistent", ret); return 0; } /* * Here we don't need to get the lock of * trans->transaction->delayed_refs, since inserted qrecord won't * be deleted, only qrecord->node may be modified (new qrecord insert) * * So modifying qrecord->old_roots is safe here */ qrecord->old_roots = ctx.roots; return 0; } /* * Inform qgroup to trace one dirty extent, specified by @bytenr and * @num_bytes. * So qgroup can account it at commit trans time. * * Better encapsulated version, with memory allocation and backref walk for * commit roots. * So this can sleep. * * Return 0 if the operation is done. * Return <0 for error, like memory allocation failure or invalid parameter * (NULL trans) */ int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr, u64 num_bytes) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_qgroup_extent_record *record; struct btrfs_delayed_ref_root *delayed_refs; const unsigned long index = (bytenr >> fs_info->sectorsize_bits); int ret; if (!btrfs_qgroup_full_accounting(fs_info) || bytenr == 0 || num_bytes == 0) return 0; record = kzalloc(sizeof(*record), GFP_NOFS); if (!record) return -ENOMEM; if (xa_reserve(&trans->transaction->delayed_refs.dirty_extents, index, GFP_NOFS)) { kfree(record); return -ENOMEM; } delayed_refs = &trans->transaction->delayed_refs; record->bytenr = bytenr; record->num_bytes = num_bytes; record->old_roots = NULL; spin_lock(&delayed_refs->lock); ret = btrfs_qgroup_trace_extent_nolock(fs_info, delayed_refs, record); spin_unlock(&delayed_refs->lock); if (ret) { /* Clean up if insertion fails or item exists. */ xa_release(&delayed_refs->dirty_extents, index); kfree(record); return 0; } return btrfs_qgroup_trace_extent_post(trans, record); } /* * Inform qgroup to trace all leaf items of data * * Return 0 for success * Return <0 for error(ENOMEM) */ int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans, struct extent_buffer *eb) { struct btrfs_fs_info *fs_info = trans->fs_info; int nr = btrfs_header_nritems(eb); int i, extent_type, ret; struct btrfs_key key; struct btrfs_file_extent_item *fi; u64 bytenr, num_bytes; /* We can be called directly from walk_up_proc() */ if (!btrfs_qgroup_full_accounting(fs_info)) return 0; for (i = 0; i < nr; i++) { btrfs_item_key_to_cpu(eb, &key, i); if (key.type != BTRFS_EXTENT_DATA_KEY) continue; fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item); /* filter out non qgroup-accountable extents */ extent_type = btrfs_file_extent_type(eb, fi); if (extent_type == BTRFS_FILE_EXTENT_INLINE) continue; bytenr = btrfs_file_extent_disk_bytenr(eb, fi); if (!bytenr) continue; num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi); ret = btrfs_qgroup_trace_extent(trans, bytenr, num_bytes); if (ret) return ret; } cond_resched(); return 0; } /* * Walk up the tree from the bottom, freeing leaves and any interior * nodes which have had all slots visited. If a node (leaf or * interior) is freed, the node above it will have it's slot * incremented. The root node will never be freed. * * At the end of this function, we should have a path which has all * slots incremented to the next position for a search. If we need to * read a new node it will be NULL and the node above it will have the * correct slot selected for a later read. * * If we increment the root nodes slot counter past the number of * elements, 1 is returned to signal completion of the search. */ static int adjust_slots_upwards(struct btrfs_path *path, int root_level) { int level = 0; int nr, slot; struct extent_buffer *eb; if (root_level == 0) return 1; while (level <= root_level) { eb = path->nodes[level]; nr = btrfs_header_nritems(eb); path->slots[level]++; slot = path->slots[level]; if (slot >= nr || level == 0) { /* * Don't free the root - we will detect this * condition after our loop and return a * positive value for caller to stop walking the tree. */ if (level != root_level) { btrfs_tree_unlock_rw(eb, path->locks[level]); path->locks[level] = 0; free_extent_buffer(eb); path->nodes[level] = NULL; path->slots[level] = 0; } } else { /* * We have a valid slot to walk back down * from. Stop here so caller can process these * new nodes. */ break; } level++; } eb = path->nodes[root_level]; if (path->slots[root_level] >= btrfs_header_nritems(eb)) return 1; return 0; } /* * Helper function to trace a subtree tree block swap. * * The swap will happen in highest tree block, but there may be a lot of * tree blocks involved. * * For example: * OO = Old tree blocks * NN = New tree blocks allocated during balance * * File tree (257) Reloc tree for 257 * L2 OO NN * / \ / \ * L1 OO OO (a) OO NN (a) * / \ / \ / \ / \ * L0 OO OO OO OO OO OO NN NN * (b) (c) (b) (c) * * When calling qgroup_trace_extent_swap(), we will pass: * @src_eb = OO(a) * @dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ] * @dst_level = 0 * @root_level = 1 * * In that case, qgroup_trace_extent_swap() will search from OO(a) to * reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty. * * The main work of qgroup_trace_extent_swap() can be split into 3 parts: * * 1) Tree search from @src_eb * It should acts as a simplified btrfs_search_slot(). * The key for search can be extracted from @dst_path->nodes[dst_level] * (first key). * * 2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty * NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty. * They should be marked during previous (@dst_level = 1) iteration. * * 3) Mark file extents in leaves dirty * We don't have good way to pick out new file extents only. * So we still follow the old method by scanning all file extents in * the leave. * * This function can free us from keeping two paths, thus later we only need * to care about how to iterate all new tree blocks in reloc tree. */ static int qgroup_trace_extent_swap(struct btrfs_trans_handle* trans, struct extent_buffer *src_eb, struct btrfs_path *dst_path, int dst_level, int root_level, bool trace_leaf) { struct btrfs_key key; struct btrfs_path *src_path; struct btrfs_fs_info *fs_info = trans->fs_info; u32 nodesize = fs_info->nodesize; int cur_level = root_level; int ret; BUG_ON(dst_level > root_level); /* Level mismatch */ if (btrfs_header_level(src_eb) != root_level) return -EINVAL; src_path = btrfs_alloc_path(); if (!src_path) { ret = -ENOMEM; goto out; } if (dst_level) btrfs_node_key_to_cpu(dst_path->nodes[dst_level], &key, 0); else btrfs_item_key_to_cpu(dst_path->nodes[dst_level], &key, 0); /* For src_path */ atomic_inc(&src_eb->refs); src_path->nodes[root_level] = src_eb; src_path->slots[root_level] = dst_path->slots[root_level]; src_path->locks[root_level] = 0; /* A simplified version of btrfs_search_slot() */ while (cur_level >= dst_level) { struct btrfs_key src_key; struct btrfs_key dst_key; if (src_path->nodes[cur_level] == NULL) { struct extent_buffer *eb; int parent_slot; eb = src_path->nodes[cur_level + 1]; parent_slot = src_path->slots[cur_level + 1]; eb = btrfs_read_node_slot(eb, parent_slot); if (IS_ERR(eb)) { ret = PTR_ERR(eb); goto out; } src_path->nodes[cur_level] = eb; btrfs_tree_read_lock(eb); src_path->locks[cur_level] = BTRFS_READ_LOCK; } src_path->slots[cur_level] = dst_path->slots[cur_level]; if (cur_level) { btrfs_node_key_to_cpu(dst_path->nodes[cur_level], &dst_key, dst_path->slots[cur_level]); btrfs_node_key_to_cpu(src_path->nodes[cur_level], &src_key, src_path->slots[cur_level]); } else { btrfs_item_key_to_cpu(dst_path->nodes[cur_level], &dst_key, dst_path->slots[cur_level]); btrfs_item_key_to_cpu(src_path->nodes[cur_level], &src_key, src_path->slots[cur_level]); } /* Content mismatch, something went wrong */ if (btrfs_comp_cpu_keys(&dst_key, &src_key)) { ret = -ENOENT; goto out; } cur_level--; } /* * Now both @dst_path and @src_path have been populated, record the tree * blocks for qgroup accounting. */ ret = btrfs_qgroup_trace_extent(trans, src_path->nodes[dst_level]->start, nodesize); if (ret < 0) goto out; ret = btrfs_qgroup_trace_extent(trans, dst_path->nodes[dst_level]->start, nodesize); if (ret < 0) goto out; /* Record leaf file extents */ if (dst_level == 0 && trace_leaf) { ret = btrfs_qgroup_trace_leaf_items(trans, src_path->nodes[0]); if (ret < 0) goto out; ret = btrfs_qgroup_trace_leaf_items(trans, dst_path->nodes[0]); } out: btrfs_free_path(src_path); return ret; } /* * Helper function to do recursive generation-aware depth-first search, to * locate all new tree blocks in a subtree of reloc tree. * * E.g. (OO = Old tree blocks, NN = New tree blocks, whose gen == last_snapshot) * reloc tree * L2 NN (a) * / \ * L1 OO NN (b) * / \ / \ * L0 OO OO OO NN * (c) (d) * If we pass: * @dst_path = [ nodes[1] = NN(b), nodes[0] = NULL ], * @cur_level = 1 * @root_level = 1 * * We will iterate through tree blocks NN(b), NN(d) and info qgroup to trace * above tree blocks along with their counter parts in file tree. * While during search, old tree blocks OO(c) will be skipped as tree block swap * won't affect OO(c). */ static int qgroup_trace_new_subtree_blocks(struct btrfs_trans_handle* trans, struct extent_buffer *src_eb, struct btrfs_path *dst_path, int cur_level, int root_level, u64 last_snapshot, bool trace_leaf) { struct btrfs_fs_info *fs_info = trans->fs_info; struct extent_buffer *eb; bool need_cleanup = false; int ret = 0; int i; /* Level sanity check */ if (cur_level < 0 || cur_level >= BTRFS_MAX_LEVEL - 1 || root_level < 0 || root_level >= BTRFS_MAX_LEVEL - 1 || root_level < cur_level) { btrfs_err_rl(fs_info, "%s: bad levels, cur_level=%d root_level=%d", __func__, cur_level, root_level); return -EUCLEAN; } /* Read the tree block if needed */ if (dst_path->nodes[cur_level] == NULL) { int parent_slot; u64 child_gen; /* * dst_path->nodes[root_level] must be initialized before * calling this function. */ if (cur_level == root_level) { btrfs_err_rl(fs_info, "%s: dst_path->nodes[%d] not initialized, root_level=%d cur_level=%d", __func__, root_level, root_level, cur_level); return -EUCLEAN; } /* * We need to get child blockptr/gen from parent before we can * read it. */ eb = dst_path->nodes[cur_level + 1]; parent_slot = dst_path->slots[cur_level + 1]; child_gen = btrfs_node_ptr_generation(eb, parent_slot); /* This node is old, no need to trace */ if (child_gen < last_snapshot) goto out; eb = btrfs_read_node_slot(eb, parent_slot); if (IS_ERR(eb)) { ret = PTR_ERR(eb); goto out; } dst_path->nodes[cur_level] = eb; dst_path->slots[cur_level] = 0; btrfs_tree_read_lock(eb); dst_path->locks[cur_level] = BTRFS_READ_LOCK; need_cleanup = true; } /* Now record this tree block and its counter part for qgroups */ ret = qgroup_trace_extent_swap(trans, src_eb, dst_path, cur_level, root_level, trace_leaf); if (ret < 0) goto cleanup; eb = dst_path->nodes[cur_level]; if (cur_level > 0) { /* Iterate all child tree blocks */ for (i = 0; i < btrfs_header_nritems(eb); i++) { /* Skip old tree blocks as they won't be swapped */ if (btrfs_node_ptr_generation(eb, i) < last_snapshot) continue; dst_path->slots[cur_level] = i; /* Recursive call (at most 7 times) */ ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, cur_level - 1, root_level, last_snapshot, trace_leaf); if (ret < 0) goto cleanup; } } cleanup: if (need_cleanup) { /* Clean up */ btrfs_tree_unlock_rw(dst_path->nodes[cur_level], dst_path->locks[cur_level]); free_extent_buffer(dst_path->nodes[cur_level]); dst_path->nodes[cur_level] = NULL; dst_path->slots[cur_level] = 0; dst_path->locks[cur_level] = 0; } out: return ret; } static int qgroup_trace_subtree_swap(struct btrfs_trans_handle *trans, struct extent_buffer *src_eb, struct extent_buffer *dst_eb, u64 last_snapshot, bool trace_leaf) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_path *dst_path = NULL; int level; int ret; if (!btrfs_qgroup_full_accounting(fs_info)) return 0; /* Wrong parameter order */ if (btrfs_header_generation(src_eb) > btrfs_header_generation(dst_eb)) { btrfs_err_rl(fs_info, "%s: bad parameter order, src_gen=%llu dst_gen=%llu", __func__, btrfs_header_generation(src_eb), btrfs_header_generation(dst_eb)); return -EUCLEAN; } if (!extent_buffer_uptodate(src_eb) || !extent_buffer_uptodate(dst_eb)) { ret = -EIO; goto out; } level = btrfs_header_level(dst_eb); dst_path = btrfs_alloc_path(); if (!dst_path) { ret = -ENOMEM; goto out; } /* For dst_path */ atomic_inc(&dst_eb->refs); dst_path->nodes[level] = dst_eb; dst_path->slots[level] = 0; dst_path->locks[level] = 0; /* Do the generation aware breadth-first search */ ret = qgroup_trace_new_subtree_blocks(trans, src_eb, dst_path, level, level, last_snapshot, trace_leaf); if (ret < 0) goto out; ret = 0; out: btrfs_free_path(dst_path); if (ret < 0) qgroup_mark_inconsistent(fs_info); return ret; } /* * Inform qgroup to trace a whole subtree, including all its child tree * blocks and data. * The root tree block is specified by @root_eb. * * Normally used by relocation(tree block swap) and subvolume deletion. * * Return 0 for success * Return <0 for error(ENOMEM or tree search error) */ int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans, struct extent_buffer *root_eb, u64 root_gen, int root_level) { struct btrfs_fs_info *fs_info = trans->fs_info; int ret = 0; int level; u8 drop_subptree_thres; struct extent_buffer *eb = root_eb; struct btrfs_path *path = NULL; ASSERT(0 <= root_level && root_level < BTRFS_MAX_LEVEL); ASSERT(root_eb != NULL); if (!btrfs_qgroup_full_accounting(fs_info)) return 0; spin_lock(&fs_info->qgroup_lock); drop_subptree_thres = fs_info->qgroup_drop_subtree_thres; spin_unlock(&fs_info->qgroup_lock); /* * This function only gets called for snapshot drop, if we hit a high * node here, it means we are going to change ownership for quite a lot * of extents, which will greatly slow down btrfs_commit_transaction(). * * So here if we find a high tree here, we just skip the accounting and * mark qgroup inconsistent. */ if (root_level >= drop_subptree_thres) { qgroup_mark_inconsistent(fs_info); return 0; } if (!extent_buffer_uptodate(root_eb)) { struct btrfs_tree_parent_check check = { .has_first_key = false, .transid = root_gen, .level = root_level }; ret = btrfs_read_extent_buffer(root_eb, &check); if (ret) goto out; } if (root_level == 0) { ret = btrfs_qgroup_trace_leaf_items(trans, root_eb); goto out; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* * Walk down the tree. Missing extent blocks are filled in as * we go. Metadata is accounted every time we read a new * extent block. * * When we reach a leaf, we account for file extent items in it, * walk back up the tree (adjusting slot pointers as we go) * and restart the search process. */ atomic_inc(&root_eb->refs); /* For path */ path->nodes[root_level] = root_eb; path->slots[root_level] = 0; path->locks[root_level] = 0; /* so release_path doesn't try to unlock */ walk_down: level = root_level; while (level >= 0) { if (path->nodes[level] == NULL) { int parent_slot; u64 child_bytenr; /* * We need to get child blockptr from parent before we * can read it. */ eb = path->nodes[level + 1]; parent_slot = path->slots[level + 1]; child_bytenr = btrfs_node_blockptr(eb, parent_slot); eb = btrfs_read_node_slot(eb, parent_slot); if (IS_ERR(eb)) { ret = PTR_ERR(eb); goto out; } path->nodes[level] = eb; path->slots[level] = 0; btrfs_tree_read_lock(eb); path->locks[level] = BTRFS_READ_LOCK; ret = btrfs_qgroup_trace_extent(trans, child_bytenr, fs_info->nodesize); if (ret) goto out; } if (level == 0) { ret = btrfs_qgroup_trace_leaf_items(trans, path->nodes[level]); if (ret) goto out; /* Nonzero return here means we completed our search */ ret = adjust_slots_upwards(path, root_level); if (ret) break; /* Restart search with new slots */ goto walk_down; } level--; } ret = 0; out: btrfs_free_path(path); return ret; } static void qgroup_iterator_nested_add(struct list_head *head, struct btrfs_qgroup *qgroup) { if (!list_empty(&qgroup->nested_iterator)) return; list_add_tail(&qgroup->nested_iterator, head); } static void qgroup_iterator_nested_clean(struct list_head *head) { while (!list_empty(head)) { struct btrfs_qgroup *qgroup; qgroup = list_first_entry(head, struct btrfs_qgroup, nested_iterator); list_del_init(&qgroup->nested_iterator); } } #define UPDATE_NEW 0 #define UPDATE_OLD 1 /* * Walk all of the roots that points to the bytenr and adjust their refcnts. */ static void qgroup_update_refcnt(struct btrfs_fs_info *fs_info, struct ulist *roots, struct list_head *qgroups, u64 seq, int update_old) { struct ulist_node *unode; struct ulist_iterator uiter; struct btrfs_qgroup *qg; if (!roots) return; ULIST_ITER_INIT(&uiter); while ((unode = ulist_next(roots, &uiter))) { LIST_HEAD(tmp); qg = find_qgroup_rb(fs_info, unode->val); if (!qg) continue; qgroup_iterator_nested_add(qgroups, qg); qgroup_iterator_add(&tmp, qg); list_for_each_entry(qg, &tmp, iterator) { struct btrfs_qgroup_list *glist; if (update_old) btrfs_qgroup_update_old_refcnt(qg, seq, 1); else btrfs_qgroup_update_new_refcnt(qg, seq, 1); list_for_each_entry(glist, &qg->groups, next_group) { qgroup_iterator_nested_add(qgroups, glist->group); qgroup_iterator_add(&tmp, glist->group); } } qgroup_iterator_clean(&tmp); } } /* * Update qgroup rfer/excl counters. * Rfer update is easy, codes can explain themselves. * * Excl update is tricky, the update is split into 2 parts. * Part 1: Possible exclusive <-> sharing detect: * | A | !A | * ------------------------------------- * B | * | - | * ------------------------------------- * !B | + | ** | * ------------------------------------- * * Conditions: * A: cur_old_roots < nr_old_roots (not exclusive before) * !A: cur_old_roots == nr_old_roots (possible exclusive before) * B: cur_new_roots < nr_new_roots (not exclusive now) * !B: cur_new_roots == nr_new_roots (possible exclusive now) * * Results: * +: Possible sharing -> exclusive -: Possible exclusive -> sharing * *: Definitely not changed. **: Possible unchanged. * * For !A and !B condition, the exception is cur_old/new_roots == 0 case. * * To make the logic clear, we first use condition A and B to split * combination into 4 results. * * Then, for result "+" and "-", check old/new_roots == 0 case, as in them * only on variant maybe 0. * * Lastly, check result **, since there are 2 variants maybe 0, split them * again(2x2). * But this time we don't need to consider other things, the codes and logic * is easy to understand now. */ static void qgroup_update_counters(struct btrfs_fs_info *fs_info, struct list_head *qgroups, u64 nr_old_roots, u64 nr_new_roots, u64 num_bytes, u64 seq) { struct btrfs_qgroup *qg; list_for_each_entry(qg, qgroups, nested_iterator) { u64 cur_new_count, cur_old_count; bool dirty = false; cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq); cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq); trace_qgroup_update_counters(fs_info, qg, cur_old_count, cur_new_count); /* Rfer update part */ if (cur_old_count == 0 && cur_new_count > 0) { qg->rfer += num_bytes; qg->rfer_cmpr += num_bytes; dirty = true; } if (cur_old_count > 0 && cur_new_count == 0) { qg->rfer -= num_bytes; qg->rfer_cmpr -= num_bytes; dirty = true; } /* Excl update part */ /* Exclusive/none -> shared case */ if (cur_old_count == nr_old_roots && cur_new_count < nr_new_roots) { /* Exclusive -> shared */ if (cur_old_count != 0) { qg->excl -= num_bytes; qg->excl_cmpr -= num_bytes; dirty = true; } } /* Shared -> exclusive/none case */ if (cur_old_count < nr_old_roots && cur_new_count == nr_new_roots) { /* Shared->exclusive */ if (cur_new_count != 0) { qg->excl += num_bytes; qg->excl_cmpr += num_bytes; dirty = true; } } /* Exclusive/none -> exclusive/none case */ if (cur_old_count == nr_old_roots && cur_new_count == nr_new_roots) { if (cur_old_count == 0) { /* None -> exclusive/none */ if (cur_new_count != 0) { /* None -> exclusive */ qg->excl += num_bytes; qg->excl_cmpr += num_bytes; dirty = true; } /* None -> none, nothing changed */ } else { /* Exclusive -> exclusive/none */ if (cur_new_count == 0) { /* Exclusive -> none */ qg->excl -= num_bytes; qg->excl_cmpr -= num_bytes; dirty = true; } /* Exclusive -> exclusive, nothing changed */ } } if (dirty) qgroup_dirty(fs_info, qg); } } /* * Check if the @roots potentially is a list of fs tree roots * * Return 0 for definitely not a fs/subvol tree roots ulist * Return 1 for possible fs/subvol tree roots in the list (considering an empty * one as well) */ static int maybe_fs_roots(struct ulist *roots) { struct ulist_node *unode; struct ulist_iterator uiter; /* Empty one, still possible for fs roots */ if (!roots || roots->nnodes == 0) return 1; ULIST_ITER_INIT(&uiter); unode = ulist_next(roots, &uiter); if (!unode) return 1; /* * If it contains fs tree roots, then it must belong to fs/subvol * trees. * If it contains a non-fs tree, it won't be shared with fs/subvol trees. */ return is_fstree(unode->val); } int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr, u64 num_bytes, struct ulist *old_roots, struct ulist *new_roots) { struct btrfs_fs_info *fs_info = trans->fs_info; LIST_HEAD(qgroups); u64 seq; u64 nr_new_roots = 0; u64 nr_old_roots = 0; int ret = 0; /* * If quotas get disabled meanwhile, the resources need to be freed and * we can't just exit here. */ if (!btrfs_qgroup_full_accounting(fs_info) || fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING) goto out_free; if (new_roots) { if (!maybe_fs_roots(new_roots)) goto out_free; nr_new_roots = new_roots->nnodes; } if (old_roots) { if (!maybe_fs_roots(old_roots)) goto out_free; nr_old_roots = old_roots->nnodes; } /* Quick exit, either not fs tree roots, or won't affect any qgroup */ if (nr_old_roots == 0 && nr_new_roots == 0) goto out_free; trace_btrfs_qgroup_account_extent(fs_info, trans->transid, bytenr, num_bytes, nr_old_roots, nr_new_roots); mutex_lock(&fs_info->qgroup_rescan_lock); if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { if (fs_info->qgroup_rescan_progress.objectid <= bytenr) { mutex_unlock(&fs_info->qgroup_rescan_lock); ret = 0; goto out_free; } } mutex_unlock(&fs_info->qgroup_rescan_lock); spin_lock(&fs_info->qgroup_lock); seq = fs_info->qgroup_seq; /* Update old refcnts using old_roots */ qgroup_update_refcnt(fs_info, old_roots, &qgroups, seq, UPDATE_OLD); /* Update new refcnts using new_roots */ qgroup_update_refcnt(fs_info, new_roots, &qgroups, seq, UPDATE_NEW); qgroup_update_counters(fs_info, &qgroups, nr_old_roots, nr_new_roots, num_bytes, seq); /* * We're done using the iterator, release all its qgroups while holding * fs_info->qgroup_lock so that we don't race with btrfs_remove_qgroup() * and trigger use-after-free accesses to qgroups. */ qgroup_iterator_nested_clean(&qgroups); /* * Bump qgroup_seq to avoid seq overlap */ fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1; spin_unlock(&fs_info->qgroup_lock); out_free: ulist_free(old_roots); ulist_free(new_roots); return ret; } int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_qgroup_extent_record *record; struct btrfs_delayed_ref_root *delayed_refs; struct ulist *new_roots = NULL; unsigned long index; u64 num_dirty_extents = 0; u64 qgroup_to_skip; int ret = 0; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) return 0; delayed_refs = &trans->transaction->delayed_refs; qgroup_to_skip = delayed_refs->qgroup_to_skip; xa_for_each(&delayed_refs->dirty_extents, index, record) { num_dirty_extents++; trace_btrfs_qgroup_account_extents(fs_info, record); if (!ret && !(fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING)) { struct btrfs_backref_walk_ctx ctx = { 0 }; ctx.bytenr = record->bytenr; ctx.fs_info = fs_info; /* * Old roots should be searched when inserting qgroup * extent record. * * But for INCONSISTENT (NO_ACCOUNTING) -> rescan case, * we may have some record inserted during * NO_ACCOUNTING (thus no old_roots populated), but * later we start rescan, which clears NO_ACCOUNTING, * leaving some inserted records without old_roots * populated. * * Those cases are rare and should not cause too much * time spent during commit_transaction(). */ if (!record->old_roots) { /* Search commit root to find old_roots */ ret = btrfs_find_all_roots(&ctx, false); if (ret < 0) goto cleanup; record->old_roots = ctx.roots; ctx.roots = NULL; } /* * Use BTRFS_SEQ_LAST as time_seq to do special search, * which doesn't lock tree or delayed_refs and search * current root. It's safe inside commit_transaction(). */ ctx.trans = trans; ctx.time_seq = BTRFS_SEQ_LAST; ret = btrfs_find_all_roots(&ctx, false); if (ret < 0) goto cleanup; new_roots = ctx.roots; if (qgroup_to_skip) { ulist_del(new_roots, qgroup_to_skip, 0); ulist_del(record->old_roots, qgroup_to_skip, 0); } ret = btrfs_qgroup_account_extent(trans, record->bytenr, record->num_bytes, record->old_roots, new_roots); record->old_roots = NULL; new_roots = NULL; } /* Free the reserved data space */ btrfs_qgroup_free_refroot(fs_info, record->data_rsv_refroot, record->data_rsv, BTRFS_QGROUP_RSV_DATA); cleanup: ulist_free(record->old_roots); ulist_free(new_roots); new_roots = NULL; xa_erase(&delayed_refs->dirty_extents, index); kfree(record); } trace_qgroup_num_dirty_extents(fs_info, trans->transid, num_dirty_extents); return ret; } /* * Writes all changed qgroups to disk. * Called by the transaction commit path and the qgroup assign ioctl. */ int btrfs_run_qgroups(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; int ret = 0; /* * In case we are called from the qgroup assign ioctl, assert that we * are holding the qgroup_ioctl_lock, otherwise we can race with a quota * disable operation (ioctl) and access a freed quota root. */ if (trans->transaction->state != TRANS_STATE_COMMIT_DOING) lockdep_assert_held(&fs_info->qgroup_ioctl_lock); if (!fs_info->quota_root) return ret; spin_lock(&fs_info->qgroup_lock); while (!list_empty(&fs_info->dirty_qgroups)) { struct btrfs_qgroup *qgroup; qgroup = list_first_entry(&fs_info->dirty_qgroups, struct btrfs_qgroup, dirty); list_del_init(&qgroup->dirty); spin_unlock(&fs_info->qgroup_lock); ret = update_qgroup_info_item(trans, qgroup); if (ret) qgroup_mark_inconsistent(fs_info); ret = update_qgroup_limit_item(trans, qgroup); if (ret) qgroup_mark_inconsistent(fs_info); spin_lock(&fs_info->qgroup_lock); } if (btrfs_qgroup_enabled(fs_info)) fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON; else fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON; spin_unlock(&fs_info->qgroup_lock); ret = update_qgroup_status_item(trans); if (ret) qgroup_mark_inconsistent(fs_info); return ret; } int btrfs_qgroup_check_inherit(struct btrfs_fs_info *fs_info, struct btrfs_qgroup_inherit *inherit, size_t size) { if (inherit->flags & ~BTRFS_QGROUP_INHERIT_FLAGS_SUPP) return -EOPNOTSUPP; if (size < sizeof(*inherit) || size > PAGE_SIZE) return -EINVAL; /* * In the past we allowed btrfs_qgroup_inherit to specify to copy * rfer/excl numbers directly from other qgroups. This behavior has * been disabled in userspace for a very long time, but here we should * also disable it in kernel, as this behavior is known to mark qgroup * inconsistent, and a rescan would wipe out the changes anyway. * * Reject any btrfs_qgroup_inherit with num_ref_copies or num_excl_copies. */ if (inherit->num_ref_copies > 0 || inherit->num_excl_copies > 0) return -EINVAL; if (size != struct_size(inherit, qgroups, inherit->num_qgroups)) return -EINVAL; /* * Skip the inherit source qgroups check if qgroup is not enabled. * Qgroup can still be later enabled causing problems, but in that case * btrfs_qgroup_inherit() would just ignore those invalid ones. */ if (!btrfs_qgroup_enabled(fs_info)) return 0; /* * Now check all the remaining qgroups, they should all: * * - Exist * - Be higher level qgroups. */ for (int i = 0; i < inherit->num_qgroups; i++) { struct btrfs_qgroup *qgroup; u64 qgroupid = inherit->qgroups[i]; if (btrfs_qgroup_level(qgroupid) == 0) return -EINVAL; spin_lock(&fs_info->qgroup_lock); qgroup = find_qgroup_rb(fs_info, qgroupid); if (!qgroup) { spin_unlock(&fs_info->qgroup_lock); return -ENOENT; } spin_unlock(&fs_info->qgroup_lock); } return 0; } static int qgroup_auto_inherit(struct btrfs_fs_info *fs_info, u64 inode_rootid, struct btrfs_qgroup_inherit **inherit) { int i = 0; u64 num_qgroups = 0; struct btrfs_qgroup *inode_qg; struct btrfs_qgroup_list *qg_list; struct btrfs_qgroup_inherit *res; size_t struct_sz; u64 *qgids; if (*inherit) return -EEXIST; inode_qg = find_qgroup_rb(fs_info, inode_rootid); if (!inode_qg) return -ENOENT; num_qgroups = list_count_nodes(&inode_qg->groups); if (!num_qgroups) return 0; struct_sz = struct_size(res, qgroups, num_qgroups); if (struct_sz == SIZE_MAX) return -ERANGE; res = kzalloc(struct_sz, GFP_NOFS); if (!res) return -ENOMEM; res->num_qgroups = num_qgroups; qgids = res->qgroups; list_for_each_entry(qg_list, &inode_qg->groups, next_group) qgids[i++] = qg_list->group->qgroupid; *inherit = res; return 0; } /* * Check if we can skip rescan when inheriting qgroups. If @src has a single * @parent, and that @parent is owning all its bytes exclusively, we can skip * the full rescan, by just adding nodesize to the @parent's excl/rfer. * * Return <0 for fatal errors (like srcid/parentid has no qgroup). * Return 0 if a quick inherit is done. * Return >0 if a quick inherit is not possible, and a full rescan is needed. */ static int qgroup_snapshot_quick_inherit(struct btrfs_fs_info *fs_info, u64 srcid, u64 parentid) { struct btrfs_qgroup *src; struct btrfs_qgroup *parent; struct btrfs_qgroup_list *list; int nr_parents = 0; src = find_qgroup_rb(fs_info, srcid); if (!src) return -ENOENT; parent = find_qgroup_rb(fs_info, parentid); if (!parent) return -ENOENT; /* * Source has no parent qgroup, but our new qgroup would have one. * Qgroup numbers would become inconsistent. */ if (list_empty(&src->groups)) return 1; list_for_each_entry(list, &src->groups, next_group) { /* The parent is not the same, quick update is not possible. */ if (list->group->qgroupid != parentid) return 1; nr_parents++; /* * More than one parent qgroup, we can't be sure about accounting * consistency. */ if (nr_parents > 1) return 1; } /* * The parent is not exclusively owning all its bytes. We're not sure * if the source has any bytes not fully owned by the parent. */ if (parent->excl != parent->rfer) return 1; parent->excl += fs_info->nodesize; parent->rfer += fs_info->nodesize; return 0; } /* * Copy the accounting information between qgroups. This is necessary * when a snapshot or a subvolume is created. Throwing an error will * cause a transaction abort so we take extra care here to only error * when a readonly fs is a reasonable outcome. */ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, u64 objectid, u64 inode_rootid, struct btrfs_qgroup_inherit *inherit) { int ret = 0; u64 *i_qgroups; bool committing = false; struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *quota_root; struct btrfs_qgroup *srcgroup; struct btrfs_qgroup *dstgroup; struct btrfs_qgroup *prealloc; struct btrfs_qgroup_list **qlist_prealloc = NULL; bool free_inherit = false; 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. * * One in create_subvol() in the ioctl context, which needs to hold * the qgroup_ioctl_lock. * * The other one in create_pending_snapshot() where no other qgroup * code can modify the fs as they all need to either start a new trans * or hold a trans handler, thus we don't need to hold * qgroup_ioctl_lock. * This would avoid long and complex lock chain and make lockdep happy. */ spin_lock(&fs_info->trans_lock); if (trans->transaction->state == TRANS_STATE_COMMIT_DOING) committing = true; spin_unlock(&fs_info->trans_lock); if (!committing) mutex_lock(&fs_info->qgroup_ioctl_lock); if (!btrfs_qgroup_enabled(fs_info)) goto out; quota_root = fs_info->quota_root; if (!quota_root) { ret = -EINVAL; goto out; } if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE && !inherit) { ret = qgroup_auto_inherit(fs_info, inode_rootid, &inherit); if (ret) goto out; free_inherit = true; } if (inherit) { i_qgroups = (u64 *)(inherit + 1); nums = inherit->num_qgroups + 2 * inherit->num_ref_copies + 2 * inherit->num_excl_copies; for (int i = 0; i < nums; i++) { srcgroup = find_qgroup_rb(fs_info, *i_qgroups); /* * Zero out invalid groups so we can ignore * them later. */ if (!srcgroup || ((srcgroup->qgroupid >> 48) <= (objectid >> 48))) *i_qgroups = 0ULL; ++i_qgroups; } } /* * create a tracking group for the subvol itself */ ret = add_qgroup_item(trans, quota_root, objectid); if (ret) goto out; /* * add qgroup to all inherited groups */ if (inherit) { i_qgroups = (u64 *)(inherit + 1); for (int i = 0; i < inherit->num_qgroups; i++, i_qgroups++) { if (*i_qgroups == 0) continue; ret = add_qgroup_relation_item(trans, objectid, *i_qgroups); if (ret && ret != -EEXIST) goto out; ret = add_qgroup_relation_item(trans, *i_qgroups, objectid); if (ret && ret != -EEXIST) goto out; } ret = 0; qlist_prealloc = kcalloc(inherit->num_qgroups, sizeof(struct btrfs_qgroup_list *), GFP_NOFS); if (!qlist_prealloc) { ret = -ENOMEM; goto out; } for (int i = 0; i < inherit->num_qgroups; i++) { qlist_prealloc[i] = kzalloc(sizeof(struct btrfs_qgroup_list), GFP_NOFS); if (!qlist_prealloc[i]) { ret = -ENOMEM; goto out; } } } spin_lock(&fs_info->qgroup_lock); 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; dstgroup->max_rfer = inherit->lim.max_rfer; dstgroup->max_excl = inherit->lim.max_excl; dstgroup->rsv_rfer = inherit->lim.rsv_rfer; dstgroup->rsv_excl = inherit->lim.rsv_excl; qgroup_dirty(fs_info, dstgroup); } if (srcid && btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_FULL) { srcgroup = find_qgroup_rb(fs_info, srcid); if (!srcgroup) goto unlock; /* * We call inherit after we clone the root in order to make sure * our counts don't go crazy, so at this point the only * difference between the two roots should be the root node. */ level_size = fs_info->nodesize; dstgroup->rfer = srcgroup->rfer; dstgroup->rfer_cmpr = srcgroup->rfer_cmpr; dstgroup->excl = level_size; dstgroup->excl_cmpr = level_size; srcgroup->excl = level_size; srcgroup->excl_cmpr = level_size; /* inherit the limit info */ dstgroup->lim_flags = srcgroup->lim_flags; dstgroup->max_rfer = srcgroup->max_rfer; dstgroup->max_excl = srcgroup->max_excl; dstgroup->rsv_rfer = srcgroup->rsv_rfer; dstgroup->rsv_excl = srcgroup->rsv_excl; qgroup_dirty(fs_info, dstgroup); qgroup_dirty(fs_info, srcgroup); /* * If the source qgroup has parent but the new one doesn't, * we need a full rescan. */ if (!inherit && !list_empty(&srcgroup->groups)) need_rescan = true; } if (!inherit) goto unlock; i_qgroups = (u64 *)(inherit + 1); for (int i = 0; i < inherit->num_qgroups; i++) { if (*i_qgroups) { ret = add_relation_rb(fs_info, qlist_prealloc[i], objectid, *i_qgroups); qlist_prealloc[i] = NULL; if (ret) goto unlock; } if (srcid) { /* Check if we can do a quick inherit. */ ret = qgroup_snapshot_quick_inherit(fs_info, srcid, *i_qgroups); if (ret < 0) goto unlock; if (ret > 0) need_rescan = true; ret = 0; } ++i_qgroups; } for (int i = 0; i < inherit->num_ref_copies; i++, i_qgroups += 2) { struct btrfs_qgroup *src; struct btrfs_qgroup *dst; if (!i_qgroups[0] || !i_qgroups[1]) continue; src = find_qgroup_rb(fs_info, i_qgroups[0]); dst = find_qgroup_rb(fs_info, i_qgroups[1]); if (!src || !dst) { ret = -EINVAL; goto unlock; } dst->rfer = src->rfer - level_size; dst->rfer_cmpr = src->rfer_cmpr - level_size; /* Manually tweaking numbers certainly needs a rescan */ need_rescan = true; } for (int i = 0; i < inherit->num_excl_copies; i++, i_qgroups += 2) { struct btrfs_qgroup *src; struct btrfs_qgroup *dst; if (!i_qgroups[0] || !i_qgroups[1]) continue; src = find_qgroup_rb(fs_info, i_qgroups[0]); dst = find_qgroup_rb(fs_info, i_qgroups[1]); if (!src || !dst) { ret = -EINVAL; goto unlock; } dst->excl = src->excl + level_size; dst->excl_cmpr = src->excl_cmpr + level_size; need_rescan = true; } unlock: spin_unlock(&fs_info->qgroup_lock); if (!ret) ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup); out: if (!committing) mutex_unlock(&fs_info->qgroup_ioctl_lock); if (need_rescan) qgroup_mark_inconsistent(fs_info); if (qlist_prealloc) { for (int i = 0; i < inherit->num_qgroups; i++) kfree(qlist_prealloc[i]); kfree(qlist_prealloc); } if (free_inherit) kfree(inherit); kfree(prealloc); return ret; } static bool qgroup_check_limits(const struct btrfs_qgroup *qg, u64 num_bytes) { if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) && qgroup_rsv_total(qg) + (s64)qg->rfer + num_bytes > qg->max_rfer) return false; if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) && qgroup_rsv_total(qg) + (s64)qg->excl + num_bytes > qg->max_excl) return false; return true; } static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce, enum btrfs_qgroup_rsv_type type) { struct btrfs_qgroup *qgroup; struct btrfs_fs_info *fs_info = root->fs_info; u64 ref_root = btrfs_root_id(root); int ret = 0; LIST_HEAD(qgroup_list); if (!is_fstree(ref_root)) return 0; if (num_bytes == 0) return 0; if (test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags) && capable(CAP_SYS_RESOURCE)) enforce = false; spin_lock(&fs_info->qgroup_lock); if (!fs_info->quota_root) goto out; qgroup = find_qgroup_rb(fs_info, ref_root); if (!qgroup) goto out; qgroup_iterator_add(&qgroup_list, qgroup); list_for_each_entry(qgroup, &qgroup_list, iterator) { struct btrfs_qgroup_list *glist; if (enforce && !qgroup_check_limits(qgroup, num_bytes)) { ret = -EDQUOT; goto out; } list_for_each_entry(glist, &qgroup->groups, next_group) qgroup_iterator_add(&qgroup_list, glist->group); } ret = 0; /* * no limits exceeded, now record the reservation into all qgroups */ list_for_each_entry(qgroup, &qgroup_list, iterator) qgroup_rsv_add(fs_info, qgroup, num_bytes, type); out: qgroup_iterator_clean(&qgroup_list); spin_unlock(&fs_info->qgroup_lock); return ret; } /* * Free @num_bytes of reserved space with @type for qgroup. (Normally level 0 * qgroup). * * Will handle all higher level qgroup too. * * NOTE: If @num_bytes is (u64)-1, this means to free all bytes of this qgroup. * This special case is only used for META_PERTRANS type. */ void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info, u64 ref_root, u64 num_bytes, enum btrfs_qgroup_rsv_type type) { struct btrfs_qgroup *qgroup; LIST_HEAD(qgroup_list); if (!is_fstree(ref_root)) return; if (num_bytes == 0) return; if (num_bytes == (u64)-1 && type != BTRFS_QGROUP_RSV_META_PERTRANS) { WARN(1, "%s: Invalid type to free", __func__); return; } spin_lock(&fs_info->qgroup_lock); if (!fs_info->quota_root) goto out; qgroup = find_qgroup_rb(fs_info, ref_root); if (!qgroup) goto out; if (num_bytes == (u64)-1) /* * We're freeing all pertrans rsv, get reserved value from * level 0 qgroup as real num_bytes to free. */ num_bytes = qgroup->rsv.values[type]; qgroup_iterator_add(&qgroup_list, qgroup); list_for_each_entry(qgroup, &qgroup_list, iterator) { struct btrfs_qgroup_list *glist; qgroup_rsv_release(fs_info, qgroup, num_bytes, type); list_for_each_entry(glist, &qgroup->groups, next_group) { qgroup_iterator_add(&qgroup_list, glist->group); } } out: qgroup_iterator_clean(&qgroup_list); spin_unlock(&fs_info->qgroup_lock); } /* * Check if the leaf is the last leaf. Which means all node pointers * are at their last position. */ static bool is_last_leaf(struct btrfs_path *path) { int i; for (i = 1; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { if (path->slots[i] != btrfs_header_nritems(path->nodes[i]) - 1) return false; } return true; } /* * returns < 0 on error, 0 when more leafs are to be scanned. * returns 1 when done. */ static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans, struct btrfs_path *path) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *extent_root; struct btrfs_key found; struct extent_buffer *scratch_leaf = NULL; u64 num_bytes; bool done; int slot; int ret; if (!btrfs_qgroup_full_accounting(fs_info)) return 1; mutex_lock(&fs_info->qgroup_rescan_lock); extent_root = btrfs_extent_root(fs_info, fs_info->qgroup_rescan_progress.objectid); ret = btrfs_search_slot_for_read(extent_root, &fs_info->qgroup_rescan_progress, path, 1, 0); btrfs_debug(fs_info, "current progress key (%llu %u %llu), search_slot ret %d", fs_info->qgroup_rescan_progress.objectid, fs_info->qgroup_rescan_progress.type, fs_info->qgroup_rescan_progress.offset, ret); if (ret) { /* * The rescan is about to end, we will not be scanning any * further blocks. We cannot unset the RESCAN flag here, because * we want to commit the transaction if everything went well. * To make the live accounting work in this phase, we set our * scan progress pointer such that every real extent objectid * will be smaller. */ fs_info->qgroup_rescan_progress.objectid = (u64)-1; btrfs_release_path(path); mutex_unlock(&fs_info->qgroup_rescan_lock); return ret; } done = is_last_leaf(path); btrfs_item_key_to_cpu(path->nodes[0], &found, btrfs_header_nritems(path->nodes[0]) - 1); fs_info->qgroup_rescan_progress.objectid = found.objectid + 1; scratch_leaf = btrfs_clone_extent_buffer(path->nodes[0]); if (!scratch_leaf) { ret = -ENOMEM; mutex_unlock(&fs_info->qgroup_rescan_lock); goto out; } slot = path->slots[0]; btrfs_release_path(path); mutex_unlock(&fs_info->qgroup_rescan_lock); for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) { struct btrfs_backref_walk_ctx ctx = { 0 }; btrfs_item_key_to_cpu(scratch_leaf, &found, slot); if (found.type != BTRFS_EXTENT_ITEM_KEY && found.type != BTRFS_METADATA_ITEM_KEY) continue; if (found.type == BTRFS_METADATA_ITEM_KEY) num_bytes = fs_info->nodesize; else num_bytes = found.offset; ctx.bytenr = found.objectid; ctx.fs_info = fs_info; ret = btrfs_find_all_roots(&ctx, false); if (ret < 0) goto out; /* For rescan, just pass old_roots as NULL */ ret = btrfs_qgroup_account_extent(trans, found.objectid, num_bytes, NULL, ctx.roots); if (ret < 0) goto out; } out: if (scratch_leaf) free_extent_buffer(scratch_leaf); if (done && !ret) { ret = 1; fs_info->qgroup_rescan_progress.objectid = (u64)-1; } return ret; } static bool rescan_should_stop(struct btrfs_fs_info *fs_info) { if (btrfs_fs_closing(fs_info)) return true; if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state)) return true; if (!btrfs_qgroup_enabled(fs_info)) return true; if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) return true; return false; } static void btrfs_qgroup_rescan_worker(struct btrfs_work *work) { struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info, qgroup_rescan_work); struct btrfs_path *path; struct btrfs_trans_handle *trans = NULL; int ret = 0; bool stopped = false; bool did_leaf_rescans = false; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) return; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } /* * Rescan should only search for commit root, and any later difference * should be recorded by qgroup */ path->search_commit_root = 1; path->skip_locking = 1; while (!ret && !(stopped = rescan_should_stop(fs_info))) { trans = btrfs_start_transaction(fs_info->fs_root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); break; } ret = qgroup_rescan_leaf(trans, path); did_leaf_rescans = true; if (ret > 0) btrfs_commit_transaction(trans); else btrfs_end_transaction(trans); } out: btrfs_free_path(path); mutex_lock(&fs_info->qgroup_rescan_lock); if (ret > 0 && fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) { fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT; } else if (ret < 0 || stopped) { fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT; } mutex_unlock(&fs_info->qgroup_rescan_lock); /* * Only update status, since the previous part has already updated the * qgroup info, and only if we did any actual work. This also prevents * race with a concurrent quota disable, which has already set * fs_info->quota_root to NULL and cleared BTRFS_FS_QUOTA_ENABLED at * btrfs_quota_disable(). */ if (did_leaf_rescans) { trans = btrfs_start_transaction(fs_info->quota_root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; btrfs_err(fs_info, "fail to start transaction for status update: %d", ret); } } else { trans = NULL; } mutex_lock(&fs_info->qgroup_rescan_lock); if (!stopped || fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN; if (trans) { int ret2 = update_qgroup_status_item(trans); if (ret2 < 0) { ret = ret2; btrfs_err(fs_info, "fail to update qgroup status: %d", ret); } } fs_info->qgroup_rescan_running = false; fs_info->qgroup_flags &= ~BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN; complete_all(&fs_info->qgroup_rescan_completion); mutex_unlock(&fs_info->qgroup_rescan_lock); if (!trans) return; btrfs_end_transaction(trans); if (stopped) { btrfs_info(fs_info, "qgroup scan paused"); } else if (fs_info->qgroup_flags & BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN) { btrfs_info(fs_info, "qgroup scan cancelled"); } else if (ret >= 0) { btrfs_info(fs_info, "qgroup scan completed%s", ret > 0 ? " (inconsistency flag cleared)" : ""); } else { btrfs_err(fs_info, "qgroup scan failed with %d", ret); } } /* * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all * memory required for the rescan context. */ static int qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid, int init_flags) { int ret = 0; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_SIMPLE) { btrfs_warn(fs_info, "qgroup rescan init failed, running in simple mode"); return -EINVAL; } if (!init_flags) { /* we're resuming qgroup rescan at mount time */ if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)) { btrfs_debug(fs_info, "qgroup rescan init failed, qgroup rescan is not queued"); ret = -EINVAL; } else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)) { btrfs_debug(fs_info, "qgroup rescan init failed, qgroup is not enabled"); ret = -ENOTCONN; } if (ret) return ret; } mutex_lock(&fs_info->qgroup_rescan_lock); if (init_flags) { if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { ret = -EINPROGRESS; } else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)) { btrfs_debug(fs_info, "qgroup rescan init failed, qgroup is not enabled"); ret = -ENOTCONN; } else if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED) { /* Quota disable is in progress */ ret = -EBUSY; } if (ret) { mutex_unlock(&fs_info->qgroup_rescan_lock); return ret; } fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN; } memset(&fs_info->qgroup_rescan_progress, 0, sizeof(fs_info->qgroup_rescan_progress)); fs_info->qgroup_flags &= ~(BTRFS_QGROUP_RUNTIME_FLAG_CANCEL_RESCAN | BTRFS_QGROUP_RUNTIME_FLAG_NO_ACCOUNTING); fs_info->qgroup_rescan_progress.objectid = progress_objectid; init_completion(&fs_info->qgroup_rescan_completion); mutex_unlock(&fs_info->qgroup_rescan_lock); btrfs_init_work(&fs_info->qgroup_rescan_work, btrfs_qgroup_rescan_worker, NULL); return 0; } static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info) { struct rb_node *n; struct btrfs_qgroup *qgroup; spin_lock(&fs_info->qgroup_lock); /* clear all current qgroup tracking information */ for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) { qgroup = rb_entry(n, struct btrfs_qgroup, node); qgroup->rfer = 0; qgroup->rfer_cmpr = 0; qgroup->excl = 0; qgroup->excl_cmpr = 0; qgroup_dirty(fs_info, qgroup); } spin_unlock(&fs_info->qgroup_lock); } int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info) { int ret = 0; ret = qgroup_rescan_init(fs_info, 0, 1); if (ret) return ret; /* * We have set the rescan_progress to 0, which means no more * delayed refs will be accounted by btrfs_qgroup_account_ref. * However, btrfs_qgroup_account_ref may be right after its call * to btrfs_find_all_roots, in which case it would still do the * accounting. * To solve this, we're committing the transaction, which will * ensure we run all delayed refs and only after that, we are * going to clear all tracking information for a clean start. */ ret = btrfs_commit_current_transaction(fs_info->fs_root); if (ret) { fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN; return ret; } qgroup_rescan_zero_tracking(fs_info); mutex_lock(&fs_info->qgroup_rescan_lock); fs_info->qgroup_rescan_running = true; btrfs_queue_work(fs_info->qgroup_rescan_workers, &fs_info->qgroup_rescan_work); mutex_unlock(&fs_info->qgroup_rescan_lock); return 0; } int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info, bool interruptible) { int running; int ret = 0; mutex_lock(&fs_info->qgroup_rescan_lock); running = fs_info->qgroup_rescan_running; mutex_unlock(&fs_info->qgroup_rescan_lock); if (!running) return 0; if (interruptible) ret = wait_for_completion_interruptible( &fs_info->qgroup_rescan_completion); else wait_for_completion(&fs_info->qgroup_rescan_completion); return ret; } /* * this is only called from open_ctree where we're still single threaded, thus * locking is omitted here. */ void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info) { if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { mutex_lock(&fs_info->qgroup_rescan_lock); fs_info->qgroup_rescan_running = true; btrfs_queue_work(fs_info->qgroup_rescan_workers, &fs_info->qgroup_rescan_work); mutex_unlock(&fs_info->qgroup_rescan_lock); } } #define rbtree_iterate_from_safe(node, next, start) \ for (node = start; node && ({ next = rb_next(node); 1;}); node = next) static int qgroup_unreserve_range(struct btrfs_inode *inode, struct extent_changeset *reserved, u64 start, u64 len) { struct rb_node *node; struct rb_node *next; struct ulist_node *entry; int ret = 0; node = reserved->range_changed.root.rb_node; if (!node) return 0; while (node) { entry = rb_entry(node, struct ulist_node, rb_node); if (entry->val < start) node = node->rb_right; else node = node->rb_left; } if (entry->val > start && rb_prev(&entry->rb_node)) entry = rb_entry(rb_prev(&entry->rb_node), struct ulist_node, rb_node); rbtree_iterate_from_safe(node, next, &entry->rb_node) { u64 entry_start; u64 entry_end; u64 entry_len; int clear_ret; entry = rb_entry(node, struct ulist_node, rb_node); entry_start = entry->val; entry_end = entry->aux; entry_len = entry_end - entry_start + 1; if (entry_start >= start + len) break; if (entry_start + entry_len <= start) continue; /* * Now the entry is in [start, start + len), revert the * EXTENT_QGROUP_RESERVED bit. */ clear_ret = clear_extent_bits(&inode->io_tree, entry_start, entry_end, EXTENT_QGROUP_RESERVED); if (!ret && clear_ret < 0) ret = clear_ret; ulist_del(&reserved->range_changed, entry->val, entry->aux); if (likely(reserved->bytes_changed >= entry_len)) { reserved->bytes_changed -= entry_len; } else { WARN_ON(1); reserved->bytes_changed = 0; } } return ret; } /* * Try to free some space for qgroup. * * For qgroup, there are only 3 ways to free qgroup space: * - Flush nodatacow write * Any nodatacow write will free its reserved data space at run_delalloc_range(). * In theory, we should only flush nodatacow inodes, but it's not yet * possible, so we need to flush the whole root. * * - Wait for ordered extents * When ordered extents are finished, their reserved metadata is finally * converted to per_trans status, which can be freed by later commit * transaction. * * - Commit transaction * This would free the meta_per_trans space. * In theory this shouldn't provide much space, but any more qgroup space * is needed. */ static int try_flush_qgroup(struct btrfs_root *root) { int ret; /* Can't hold an open transaction or we run the risk of deadlocking. */ ASSERT(current->journal_info == NULL); if (WARN_ON(current->journal_info)) return 0; /* * We don't want to run flush again and again, so if there is a running * one, we won't try to start a new flush, but exit directly. */ if (test_and_set_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)) { wait_event(root->qgroup_flush_wait, !test_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state)); return 0; } btrfs_run_delayed_iputs(root->fs_info); btrfs_wait_on_delayed_iputs(root->fs_info); ret = btrfs_start_delalloc_snapshot(root, true); if (ret < 0) goto out; btrfs_wait_ordered_extents(root, U64_MAX, NULL); ret = btrfs_commit_current_transaction(root); out: clear_bit(BTRFS_ROOT_QGROUP_FLUSHING, &root->state); wake_up(&root->qgroup_flush_wait); return ret; } static int qgroup_reserve_data(struct btrfs_inode *inode, struct extent_changeset **reserved_ret, u64 start, u64 len) { struct btrfs_root *root = inode->root; struct extent_changeset *reserved; bool new_reserved = false; u64 orig_reserved; u64 to_reserve; int ret; if (btrfs_qgroup_mode(root->fs_info) == BTRFS_QGROUP_MODE_DISABLED || !is_fstree(btrfs_root_id(root)) || len == 0) return 0; /* @reserved parameter is mandatory for qgroup */ if (WARN_ON(!reserved_ret)) return -EINVAL; if (!*reserved_ret) { new_reserved = true; *reserved_ret = extent_changeset_alloc(); if (!*reserved_ret) return -ENOMEM; } reserved = *reserved_ret; /* Record already reserved space */ orig_reserved = reserved->bytes_changed; ret = set_record_extent_bits(&inode->io_tree, start, start + len -1, EXTENT_QGROUP_RESERVED, reserved); /* Newly reserved space */ to_reserve = reserved->bytes_changed - orig_reserved; trace_btrfs_qgroup_reserve_data(&inode->vfs_inode, start, len, to_reserve, QGROUP_RESERVE); if (ret < 0) goto out; ret = qgroup_reserve(root, to_reserve, true, BTRFS_QGROUP_RSV_DATA); if (ret < 0) goto cleanup; return ret; cleanup: qgroup_unreserve_range(inode, reserved, start, len); out: if (new_reserved) { extent_changeset_free(reserved); *reserved_ret = NULL; } return ret; } /* * Reserve qgroup space for range [start, start + len). * * This function will either reserve space from related qgroups or do nothing * if the range is already reserved. * * Return 0 for successful reservation * Return <0 for error (including -EQUOT) * * NOTE: This function may sleep for memory allocation, dirty page flushing and * commit transaction. So caller should not hold any dirty page locked. */ int btrfs_qgroup_reserve_data(struct btrfs_inode *inode, struct extent_changeset **reserved_ret, u64 start, u64 len) { int ret; ret = qgroup_reserve_data(inode, reserved_ret, start, len); if (ret <= 0 && ret != -EDQUOT) return ret; ret = try_flush_qgroup(inode->root); if (ret < 0) return ret; return qgroup_reserve_data(inode, reserved_ret, start, len); } /* Free ranges specified by @reserved, normally in error path */ static int qgroup_free_reserved_data(struct btrfs_inode *inode, struct extent_changeset *reserved, u64 start, u64 len, u64 *freed_ret) { struct btrfs_root *root = inode->root; struct ulist_node *unode; struct ulist_iterator uiter; struct extent_changeset changeset; u64 freed = 0; int ret; extent_changeset_init(&changeset); len = round_up(start + len, root->fs_info->sectorsize); start = round_down(start, root->fs_info->sectorsize); ULIST_ITER_INIT(&uiter); while ((unode = ulist_next(&reserved->range_changed, &uiter))) { u64 range_start = unode->val; /* unode->aux is the inclusive end */ u64 range_len = unode->aux - range_start + 1; u64 free_start; u64 free_len; extent_changeset_release(&changeset); /* Only free range in range [start, start + len) */ if (range_start >= start + len || range_start + range_len <= start) continue; free_start = max(range_start, start); free_len = min(start + len, range_start + range_len) - free_start; /* * TODO: To also modify reserved->ranges_reserved to reflect * the modification. * * However as long as we free qgroup reserved according to * EXTENT_QGROUP_RESERVED, we won't double free. * So not need to rush. */ ret = clear_record_extent_bits(&inode->io_tree, free_start, free_start + free_len - 1, EXTENT_QGROUP_RESERVED, &changeset); if (ret < 0) goto out; freed += changeset.bytes_changed; } btrfs_qgroup_free_refroot(root->fs_info, btrfs_root_id(root), freed, BTRFS_QGROUP_RSV_DATA); if (freed_ret) *freed_ret = freed; ret = 0; out: extent_changeset_release(&changeset); return ret; } static int __btrfs_qgroup_release_data(struct btrfs_inode *inode, struct extent_changeset *reserved, u64 start, u64 len, u64 *released, int free) { struct extent_changeset changeset; int trace_op = QGROUP_RELEASE; int ret; if (btrfs_qgroup_mode(inode->root->fs_info) == BTRFS_QGROUP_MODE_DISABLED) { return clear_record_extent_bits(&inode->io_tree, start, start + len - 1, EXTENT_QGROUP_RESERVED, NULL); } /* In release case, we shouldn't have @reserved */ WARN_ON(!free && reserved); if (free && reserved) return qgroup_free_reserved_data(inode, reserved, start, len, released); extent_changeset_init(&changeset); ret = clear_record_extent_bits(&inode->io_tree, start, start + len -1, EXTENT_QGROUP_RESERVED, &changeset); if (ret < 0) goto out; if (free) trace_op = QGROUP_FREE; trace_btrfs_qgroup_release_data(&inode->vfs_inode, start, len, changeset.bytes_changed, trace_op); if (free) btrfs_qgroup_free_refroot(inode->root->fs_info, btrfs_root_id(inode->root), changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA); if (released) *released = changeset.bytes_changed; out: extent_changeset_release(&changeset); return ret; } /* * Free a reserved space range from io_tree and related qgroups * * Should be called when a range of pages get invalidated before reaching disk. * Or for error cleanup case. * if @reserved is given, only reserved range in [@start, @start + @len) will * be freed. * * For data written to disk, use btrfs_qgroup_release_data(). * * NOTE: This function may sleep for memory allocation. */ int btrfs_qgroup_free_data(struct btrfs_inode *inode, struct extent_changeset *reserved, u64 start, u64 len, u64 *freed) { return __btrfs_qgroup_release_data(inode, reserved, start, len, freed, 1); } /* * Release a reserved space range from io_tree only. * * Should be called when a range of pages get written to disk and corresponding * FILE_EXTENT is inserted into corresponding root. * * Since new qgroup accounting framework will only update qgroup numbers at * commit_transaction() time, its reserved space shouldn't be freed from * related qgroups. * * But we should release the range from io_tree, to allow further write to be * COWed. * * NOTE: This function may sleep for memory allocation. */ int btrfs_qgroup_release_data(struct btrfs_inode *inode, u64 start, u64 len, u64 *released) { return __btrfs_qgroup_release_data(inode, NULL, start, len, released, 0); } static void add_root_meta_rsv(struct btrfs_root *root, int num_bytes, enum btrfs_qgroup_rsv_type type) { if (type != BTRFS_QGROUP_RSV_META_PREALLOC && type != BTRFS_QGROUP_RSV_META_PERTRANS) return; if (num_bytes == 0) return; spin_lock(&root->qgroup_meta_rsv_lock); if (type == BTRFS_QGROUP_RSV_META_PREALLOC) root->qgroup_meta_rsv_prealloc += num_bytes; else root->qgroup_meta_rsv_pertrans += num_bytes; spin_unlock(&root->qgroup_meta_rsv_lock); } static int sub_root_meta_rsv(struct btrfs_root *root, int num_bytes, enum btrfs_qgroup_rsv_type type) { if (type != BTRFS_QGROUP_RSV_META_PREALLOC && type != BTRFS_QGROUP_RSV_META_PERTRANS) return 0; if (num_bytes == 0) return 0; spin_lock(&root->qgroup_meta_rsv_lock); if (type == BTRFS_QGROUP_RSV_META_PREALLOC) { num_bytes = min_t(u64, root->qgroup_meta_rsv_prealloc, num_bytes); root->qgroup_meta_rsv_prealloc -= num_bytes; } else { num_bytes = min_t(u64, root->qgroup_meta_rsv_pertrans, num_bytes); root->qgroup_meta_rsv_pertrans -= num_bytes; } spin_unlock(&root->qgroup_meta_rsv_lock); return num_bytes; } int btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, enum btrfs_qgroup_rsv_type type, bool enforce) { struct btrfs_fs_info *fs_info = root->fs_info; int ret; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED || !is_fstree(btrfs_root_id(root)) || num_bytes == 0) return 0; BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize)); trace_qgroup_meta_reserve(root, (s64)num_bytes, type); ret = qgroup_reserve(root, num_bytes, enforce, type); if (ret < 0) return ret; /* * Record what we have reserved into root. * * To avoid quota disabled->enabled underflow. * In that case, we may try to free space we haven't reserved * (since quota was disabled), so record what we reserved into root. * And ensure later release won't underflow this number. */ add_root_meta_rsv(root, num_bytes, type); return ret; } int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes, enum btrfs_qgroup_rsv_type type, bool enforce, bool noflush) { int ret; ret = btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce); if ((ret <= 0 && ret != -EDQUOT) || noflush) return ret; ret = try_flush_qgroup(root); if (ret < 0) return ret; return btrfs_qgroup_reserve_meta(root, num_bytes, type, enforce); } /* * Per-transaction meta reservation should be all freed at transaction commit * time */ void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED || !is_fstree(btrfs_root_id(root))) return; /* TODO: Update trace point to handle such free */ trace_qgroup_meta_free_all_pertrans(root); /* Special value -1 means to free all reserved space */ btrfs_qgroup_free_refroot(fs_info, btrfs_root_id(root), (u64)-1, BTRFS_QGROUP_RSV_META_PERTRANS); } void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes, enum btrfs_qgroup_rsv_type type) { struct btrfs_fs_info *fs_info = root->fs_info; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED || !is_fstree(btrfs_root_id(root))) return; /* * reservation for META_PREALLOC can happen before quota is enabled, * which can lead to underflow. * Here ensure we will only free what we really have reserved. */ num_bytes = sub_root_meta_rsv(root, num_bytes, type); BUG_ON(num_bytes != round_down(num_bytes, fs_info->nodesize)); trace_qgroup_meta_reserve(root, -(s64)num_bytes, type); btrfs_qgroup_free_refroot(fs_info, btrfs_root_id(root), num_bytes, type); } static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root, int num_bytes) { struct btrfs_qgroup *qgroup; LIST_HEAD(qgroup_list); if (num_bytes == 0) return; if (!fs_info->quota_root) return; spin_lock(&fs_info->qgroup_lock); qgroup = find_qgroup_rb(fs_info, ref_root); if (!qgroup) goto out; qgroup_iterator_add(&qgroup_list, qgroup); list_for_each_entry(qgroup, &qgroup_list, iterator) { struct btrfs_qgroup_list *glist; qgroup_rsv_release(fs_info, qgroup, num_bytes, BTRFS_QGROUP_RSV_META_PREALLOC); if (!sb_rdonly(fs_info->sb)) qgroup_rsv_add(fs_info, qgroup, num_bytes, BTRFS_QGROUP_RSV_META_PERTRANS); list_for_each_entry(glist, &qgroup->groups, next_group) qgroup_iterator_add(&qgroup_list, glist->group); } out: qgroup_iterator_clean(&qgroup_list); spin_unlock(&fs_info->qgroup_lock); } /* * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS. * * This is called when preallocated meta reservation needs to be used. * Normally after btrfs_join_transaction() call. */ void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes) { struct btrfs_fs_info *fs_info = root->fs_info; if (btrfs_qgroup_mode(fs_info) == BTRFS_QGROUP_MODE_DISABLED || !is_fstree(btrfs_root_id(root))) return; /* Same as btrfs_qgroup_free_meta_prealloc() */ num_bytes = sub_root_meta_rsv(root, num_bytes, BTRFS_QGROUP_RSV_META_PREALLOC); trace_qgroup_meta_convert(root, num_bytes); qgroup_convert_meta(fs_info, btrfs_root_id(root), num_bytes); if (!sb_rdonly(fs_info->sb)) add_root_meta_rsv(root, num_bytes, BTRFS_QGROUP_RSV_META_PERTRANS); } /* * Check qgroup reserved space leaking, normally at destroy inode * time */ void btrfs_qgroup_check_reserved_leak(struct btrfs_inode *inode) { struct extent_changeset changeset; struct ulist_node *unode; struct ulist_iterator iter; int ret; extent_changeset_init(&changeset); ret = clear_record_extent_bits(&inode->io_tree, 0, (u64)-1, EXTENT_QGROUP_RESERVED, &changeset); WARN_ON(ret < 0); if (WARN_ON(changeset.bytes_changed)) { ULIST_ITER_INIT(&iter); while ((unode = ulist_next(&changeset.range_changed, &iter))) { btrfs_warn(inode->root->fs_info, "leaking qgroup reserved space, ino: %llu, start: %llu, end: %llu", btrfs_ino(inode), unode->val, unode->aux); } btrfs_qgroup_free_refroot(inode->root->fs_info, btrfs_root_id(inode->root), changeset.bytes_changed, BTRFS_QGROUP_RSV_DATA); } extent_changeset_release(&changeset); } void btrfs_qgroup_init_swapped_blocks( struct btrfs_qgroup_swapped_blocks *swapped_blocks) { int i; spin_lock_init(&swapped_blocks->lock); for (i = 0; i < BTRFS_MAX_LEVEL; i++) swapped_blocks->blocks[i] = RB_ROOT; swapped_blocks->swapped = false; } /* * Delete all swapped blocks record of @root. * Every record here means we skipped a full subtree scan for qgroup. * * Gets called when committing one transaction. */ void btrfs_qgroup_clean_swapped_blocks(struct btrfs_root *root) { struct btrfs_qgroup_swapped_blocks *swapped_blocks; int i; swapped_blocks = &root->swapped_blocks; spin_lock(&swapped_blocks->lock); if (!swapped_blocks->swapped) goto out; for (i = 0; i < BTRFS_MAX_LEVEL; i++) { struct rb_root *cur_root = &swapped_blocks->blocks[i]; struct btrfs_qgroup_swapped_block *entry; struct btrfs_qgroup_swapped_block *next; rbtree_postorder_for_each_entry_safe(entry, next, cur_root, node) kfree(entry); swapped_blocks->blocks[i] = RB_ROOT; } swapped_blocks->swapped = false; out: spin_unlock(&swapped_blocks->lock); } /* * Add subtree roots record into @subvol_root. * * @subvol_root: tree root of the subvolume tree get swapped * @bg: block group under balance * @subvol_parent/slot: pointer to the subtree root in subvolume tree * @reloc_parent/slot: pointer to the subtree root in reloc tree * BOTH POINTERS ARE BEFORE TREE SWAP * @last_snapshot: last snapshot generation of the subvolume tree */ int btrfs_qgroup_add_swapped_blocks(struct btrfs_trans_handle *trans, struct btrfs_root *subvol_root, struct btrfs_block_group *bg, struct extent_buffer *subvol_parent, int subvol_slot, struct extent_buffer *reloc_parent, int reloc_slot, u64 last_snapshot) { struct btrfs_fs_info *fs_info = subvol_root->fs_info; struct btrfs_qgroup_swapped_blocks *blocks = &subvol_root->swapped_blocks; struct btrfs_qgroup_swapped_block *block; struct rb_node **cur; struct rb_node *parent = NULL; int level = btrfs_header_level(subvol_parent) - 1; int ret = 0; if (!btrfs_qgroup_full_accounting(fs_info)) return 0; if (btrfs_node_ptr_generation(subvol_parent, subvol_slot) > btrfs_node_ptr_generation(reloc_parent, reloc_slot)) { btrfs_err_rl(fs_info, "%s: bad parameter order, subvol_gen=%llu reloc_gen=%llu", __func__, btrfs_node_ptr_generation(subvol_parent, subvol_slot), btrfs_node_ptr_generation(reloc_parent, reloc_slot)); return -EUCLEAN; } block = kmalloc(sizeof(*block), GFP_NOFS); if (!block) { ret = -ENOMEM; goto out; } /* * @reloc_parent/slot is still before swap, while @block is going to * record the bytenr after swap, so we do the swap here. */ block->subvol_bytenr = btrfs_node_blockptr(reloc_parent, reloc_slot); block->subvol_generation = btrfs_node_ptr_generation(reloc_parent, reloc_slot); block->reloc_bytenr = btrfs_node_blockptr(subvol_parent, subvol_slot); block->reloc_generation = btrfs_node_ptr_generation(subvol_parent, subvol_slot); block->last_snapshot = last_snapshot; block->level = level; /* * If we have bg == NULL, we're called from btrfs_recover_relocation(), * no one else can modify tree blocks thus we qgroup will not change * no matter the value of trace_leaf. */ if (bg && bg->flags & BTRFS_BLOCK_GROUP_DATA) block->trace_leaf = true; else block->trace_leaf = false; btrfs_node_key_to_cpu(reloc_parent, &block->first_key, reloc_slot); /* Insert @block into @blocks */ spin_lock(&blocks->lock); cur = &blocks->blocks[level].rb_node; while (*cur) { struct btrfs_qgroup_swapped_block *entry; parent = *cur; entry = rb_entry(parent, struct btrfs_qgroup_swapped_block, node); if (entry->subvol_bytenr < block->subvol_bytenr) { cur = &(*cur)->rb_left; } else if (entry->subvol_bytenr > block->subvol_bytenr) { cur = &(*cur)->rb_right; } else { if (entry->subvol_generation != block->subvol_generation || entry->reloc_bytenr != block->reloc_bytenr || entry->reloc_generation != block->reloc_generation) { /* * Duplicated but mismatch entry found. * Shouldn't happen. * * Marking qgroup inconsistent should be enough * for end users. */ WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG)); ret = -EEXIST; } kfree(block); goto out_unlock; } } rb_link_node(&block->node, parent, cur); rb_insert_color(&block->node, &blocks->blocks[level]); blocks->swapped = true; out_unlock: spin_unlock(&blocks->lock); out: if (ret < 0) qgroup_mark_inconsistent(fs_info); return ret; } /* * Check if the tree block is a subtree root, and if so do the needed * delayed subtree trace for qgroup. * * This is called during btrfs_cow_block(). */ int btrfs_qgroup_trace_subtree_after_cow(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *subvol_eb) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_tree_parent_check check = { 0 }; struct btrfs_qgroup_swapped_blocks *blocks = &root->swapped_blocks; struct btrfs_qgroup_swapped_block *block; struct extent_buffer *reloc_eb = NULL; struct rb_node *node; bool found = false; bool swapped = false; int level = btrfs_header_level(subvol_eb); int ret = 0; int i; if (!btrfs_qgroup_full_accounting(fs_info)) return 0; if (!is_fstree(btrfs_root_id(root)) || !root->reloc_root) return 0; spin_lock(&blocks->lock); if (!blocks->swapped) { spin_unlock(&blocks->lock); return 0; } node = blocks->blocks[level].rb_node; while (node) { block = rb_entry(node, struct btrfs_qgroup_swapped_block, node); if (block->subvol_bytenr < subvol_eb->start) { node = node->rb_left; } else if (block->subvol_bytenr > subvol_eb->start) { node = node->rb_right; } else { found = true; break; } } if (!found) { spin_unlock(&blocks->lock); goto out; } /* Found one, remove it from @blocks first and update blocks->swapped */ rb_erase(&block->node, &blocks->blocks[level]); for (i = 0; i < BTRFS_MAX_LEVEL; i++) { if (RB_EMPTY_ROOT(&blocks->blocks[i])) { swapped = true; break; } } blocks->swapped = swapped; spin_unlock(&blocks->lock); check.level = block->level; check.transid = block->reloc_generation; check.has_first_key = true; memcpy(&check.first_key, &block->first_key, sizeof(check.first_key)); /* Read out reloc subtree root */ reloc_eb = read_tree_block(fs_info, block->reloc_bytenr, &check); if (IS_ERR(reloc_eb)) { ret = PTR_ERR(reloc_eb); reloc_eb = NULL; goto free_out; } if (!extent_buffer_uptodate(reloc_eb)) { ret = -EIO; goto free_out; } ret = qgroup_trace_subtree_swap(trans, reloc_eb, subvol_eb, block->last_snapshot, block->trace_leaf); free_out: kfree(block); free_extent_buffer(reloc_eb); out: if (ret < 0) { btrfs_err_rl(fs_info, "failed to account subtree at bytenr %llu: %d", subvol_eb->start, ret); qgroup_mark_inconsistent(fs_info); } return ret; } void btrfs_qgroup_destroy_extent_records(struct btrfs_transaction *trans) { struct btrfs_qgroup_extent_record *entry; unsigned long index; xa_for_each(&trans->delayed_refs.dirty_extents, index, entry) { ulist_free(entry->old_roots); kfree(entry); } xa_destroy(&trans->delayed_refs.dirty_extents); } void btrfs_free_squota_rsv(struct btrfs_fs_info *fs_info, u64 root, u64 rsv_bytes) { if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE) return; if (!is_fstree(root)) return; btrfs_qgroup_free_refroot(fs_info, root, rsv_bytes, BTRFS_QGROUP_RSV_DATA); } int btrfs_record_squota_delta(struct btrfs_fs_info *fs_info, const struct btrfs_squota_delta *delta) { int ret; struct btrfs_qgroup *qgroup; struct btrfs_qgroup *qg; LIST_HEAD(qgroup_list); u64 root = delta->root; u64 num_bytes = delta->num_bytes; const int sign = (delta->is_inc ? 1 : -1); if (btrfs_qgroup_mode(fs_info) != BTRFS_QGROUP_MODE_SIMPLE) return 0; if (!is_fstree(root)) return 0; /* If the extent predates enabling quotas, don't count it. */ if (delta->generation < fs_info->qgroup_enable_gen) return 0; spin_lock(&fs_info->qgroup_lock); qgroup = find_qgroup_rb(fs_info, root); if (!qgroup) { ret = -ENOENT; goto out; } ret = 0; qgroup_iterator_add(&qgroup_list, qgroup); list_for_each_entry(qg, &qgroup_list, iterator) { struct btrfs_qgroup_list *glist; qg->excl += num_bytes * sign; qg->rfer += num_bytes * sign; qgroup_dirty(fs_info, qg); list_for_each_entry(glist, &qg->groups, next_group) qgroup_iterator_add(&qgroup_list, glist->group); } qgroup_iterator_clean(&qgroup_list); out: spin_unlock(&fs_info->qgroup_lock); return ret; }