156bec294SChris Mason /* 256bec294SChris Mason * Copyright (C) 2008 Oracle. All rights reserved. 356bec294SChris Mason * 456bec294SChris Mason * This program is free software; you can redistribute it and/or 556bec294SChris Mason * modify it under the terms of the GNU General Public 656bec294SChris Mason * License v2 as published by the Free Software Foundation. 756bec294SChris Mason * 856bec294SChris Mason * This program is distributed in the hope that it will be useful, 956bec294SChris Mason * but WITHOUT ANY WARRANTY; without even the implied warranty of 1056bec294SChris Mason * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 1156bec294SChris Mason * General Public License for more details. 1256bec294SChris Mason * 1356bec294SChris Mason * You should have received a copy of the GNU General Public 1456bec294SChris Mason * License along with this program; if not, write to the 1556bec294SChris Mason * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 1656bec294SChris Mason * Boston, MA 021110-1307, USA. 1756bec294SChris Mason */ 1856bec294SChris Mason #ifndef __DELAYED_REF__ 1956bec294SChris Mason #define __DELAYED_REF__ 2056bec294SChris Mason 2156bec294SChris Mason /* these are the possible values of struct btrfs_delayed_ref->action */ 2256bec294SChris Mason #define BTRFS_ADD_DELAYED_REF 1 /* add one backref to the tree */ 2356bec294SChris Mason #define BTRFS_DROP_DELAYED_REF 2 /* delete one backref from the tree */ 2456bec294SChris Mason #define BTRFS_ADD_DELAYED_EXTENT 3 /* record a full extent allocation */ 251a81af4dSChris Mason #define BTRFS_UPDATE_DELAYED_HEAD 4 /* not changing ref count on head ref */ 2656bec294SChris Mason 2756bec294SChris Mason struct btrfs_delayed_ref_node { 2856bec294SChris Mason struct rb_node rb_node; 2956bec294SChris Mason 3056bec294SChris Mason /* the starting bytenr of the extent */ 3156bec294SChris Mason u64 bytenr; 3256bec294SChris Mason 3356bec294SChris Mason /* the size of the extent */ 3456bec294SChris Mason u64 num_bytes; 3556bec294SChris Mason 3656bec294SChris Mason /* ref count on this data structure */ 3756bec294SChris Mason atomic_t refs; 3856bec294SChris Mason 3956bec294SChris Mason /* 4056bec294SChris Mason * how many refs is this entry adding or deleting. For 4156bec294SChris Mason * head refs, this may be a negative number because it is keeping 4256bec294SChris Mason * track of the total mods done to the reference count. 4356bec294SChris Mason * For individual refs, this will always be a positive number 4456bec294SChris Mason * 4556bec294SChris Mason * It may be more than one, since it is possible for a single 4656bec294SChris Mason * parent to have more than one ref on an extent 4756bec294SChris Mason */ 4856bec294SChris Mason int ref_mod; 4956bec294SChris Mason 505d4f98a2SYan Zheng unsigned int action:8; 515d4f98a2SYan Zheng unsigned int type:8; 5256bec294SChris Mason /* is this node still in the rbtree? */ 535d4f98a2SYan Zheng unsigned int is_head:1; 5456bec294SChris Mason unsigned int in_tree:1; 5556bec294SChris Mason }; 5656bec294SChris Mason 575d4f98a2SYan Zheng struct btrfs_delayed_extent_op { 585d4f98a2SYan Zheng struct btrfs_disk_key key; 595d4f98a2SYan Zheng u64 flags_to_set; 605d4f98a2SYan Zheng unsigned int update_key:1; 615d4f98a2SYan Zheng unsigned int update_flags:1; 625d4f98a2SYan Zheng unsigned int is_data:1; 635d4f98a2SYan Zheng }; 645d4f98a2SYan Zheng 6556bec294SChris Mason /* 6656bec294SChris Mason * the head refs are used to hold a lock on a given extent, which allows us 6756bec294SChris Mason * to make sure that only one process is running the delayed refs 6856bec294SChris Mason * at a time for a single extent. They also store the sum of all the 6956bec294SChris Mason * reference count modifications we've queued up. 7056bec294SChris Mason */ 7156bec294SChris Mason struct btrfs_delayed_ref_head { 7256bec294SChris Mason struct btrfs_delayed_ref_node node; 7356bec294SChris Mason 7456bec294SChris Mason /* 7556bec294SChris Mason * the mutex is held while running the refs, and it is also 7656bec294SChris Mason * held when checking the sum of reference modifications. 7756bec294SChris Mason */ 7856bec294SChris Mason struct mutex mutex; 7956bec294SChris Mason 80c3e69d58SChris Mason struct list_head cluster; 81c3e69d58SChris Mason 825d4f98a2SYan Zheng struct btrfs_delayed_extent_op *extent_op; 8356bec294SChris Mason /* 8456bec294SChris Mason * when a new extent is allocated, it is just reserved in memory 8556bec294SChris Mason * The actual extent isn't inserted into the extent allocation tree 8656bec294SChris Mason * until the delayed ref is processed. must_insert_reserved is 8756bec294SChris Mason * used to flag a delayed ref so the accounting can be updated 8856bec294SChris Mason * when a full insert is done. 8956bec294SChris Mason * 9056bec294SChris Mason * It is possible the extent will be freed before it is ever 9156bec294SChris Mason * inserted into the extent allocation tree. In this case 9256bec294SChris Mason * we need to update the in ram accounting to properly reflect 9356bec294SChris Mason * the free has happened. 9456bec294SChris Mason */ 9556bec294SChris Mason unsigned int must_insert_reserved:1; 965d4f98a2SYan Zheng unsigned int is_data:1; 9756bec294SChris Mason }; 9856bec294SChris Mason 995d4f98a2SYan Zheng struct btrfs_delayed_tree_ref { 10056bec294SChris Mason struct btrfs_delayed_ref_node node; 1015d4f98a2SYan Zheng union { 10256bec294SChris Mason u64 root; 1035d4f98a2SYan Zheng u64 parent; 1045d4f98a2SYan Zheng }; 1055d4f98a2SYan Zheng int level; 1065d4f98a2SYan Zheng }; 10756bec294SChris Mason 1085d4f98a2SYan Zheng struct btrfs_delayed_data_ref { 1095d4f98a2SYan Zheng struct btrfs_delayed_ref_node node; 1105d4f98a2SYan Zheng union { 1115d4f98a2SYan Zheng u64 root; 1125d4f98a2SYan Zheng u64 parent; 1135d4f98a2SYan Zheng }; 1145d4f98a2SYan Zheng u64 objectid; 1155d4f98a2SYan Zheng u64 offset; 11656bec294SChris Mason }; 11756bec294SChris Mason 11856bec294SChris Mason struct btrfs_delayed_ref_root { 11956bec294SChris Mason struct rb_root root; 12056bec294SChris Mason 12156bec294SChris Mason /* this spin lock protects the rbtree and the entries inside */ 12256bec294SChris Mason spinlock_t lock; 12356bec294SChris Mason 12456bec294SChris Mason /* how many delayed ref updates we've queued, used by the 12556bec294SChris Mason * throttling code 12656bec294SChris Mason */ 12756bec294SChris Mason unsigned long num_entries; 12856bec294SChris Mason 129c3e69d58SChris Mason /* total number of head nodes in tree */ 130c3e69d58SChris Mason unsigned long num_heads; 131c3e69d58SChris Mason 132c3e69d58SChris Mason /* total number of head nodes ready for processing */ 133c3e69d58SChris Mason unsigned long num_heads_ready; 134c3e69d58SChris Mason 13556bec294SChris Mason /* 13656bec294SChris Mason * set when the tree is flushing before a transaction commit, 13756bec294SChris Mason * used by the throttling code to decide if new updates need 13856bec294SChris Mason * to be run right away 13956bec294SChris Mason */ 14056bec294SChris Mason int flushing; 141c3e69d58SChris Mason 142c3e69d58SChris Mason u64 run_delayed_start; 14356bec294SChris Mason }; 14456bec294SChris Mason 14556bec294SChris Mason static inline void btrfs_put_delayed_ref(struct btrfs_delayed_ref_node *ref) 14656bec294SChris Mason { 14756bec294SChris Mason WARN_ON(atomic_read(&ref->refs) == 0); 14856bec294SChris Mason if (atomic_dec_and_test(&ref->refs)) { 14956bec294SChris Mason WARN_ON(ref->in_tree); 15056bec294SChris Mason kfree(ref); 15156bec294SChris Mason } 15256bec294SChris Mason } 15356bec294SChris Mason 1545d4f98a2SYan Zheng int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans, 1555d4f98a2SYan Zheng u64 bytenr, u64 num_bytes, u64 parent, 1565d4f98a2SYan Zheng u64 ref_root, int level, int action, 1575d4f98a2SYan Zheng struct btrfs_delayed_extent_op *extent_op); 1585d4f98a2SYan Zheng int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans, 1595d4f98a2SYan Zheng u64 bytenr, u64 num_bytes, 1605d4f98a2SYan Zheng u64 parent, u64 ref_root, 1615d4f98a2SYan Zheng u64 owner, u64 offset, int action, 1625d4f98a2SYan Zheng struct btrfs_delayed_extent_op *extent_op); 1635d4f98a2SYan Zheng int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans, 1645d4f98a2SYan Zheng u64 bytenr, u64 num_bytes, 1655d4f98a2SYan Zheng struct btrfs_delayed_extent_op *extent_op); 16656bec294SChris Mason 1671887be66SChris Mason struct btrfs_delayed_ref_head * 1681887be66SChris Mason btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr); 16956bec294SChris Mason int btrfs_delayed_ref_pending(struct btrfs_trans_handle *trans, u64 bytenr); 1705d4f98a2SYan Zheng int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans, 17156bec294SChris Mason struct btrfs_root *root, u64 bytenr, 1725d4f98a2SYan Zheng u64 num_bytes, u64 *refs, u64 *flags); 17356bec294SChris Mason int btrfs_update_delayed_ref(struct btrfs_trans_handle *trans, 17456bec294SChris Mason u64 bytenr, u64 num_bytes, u64 orig_parent, 17556bec294SChris Mason u64 parent, u64 orig_ref_root, u64 ref_root, 17656bec294SChris Mason u64 orig_ref_generation, u64 ref_generation, 17756bec294SChris Mason u64 owner_objectid, int pin); 178c3e69d58SChris Mason int btrfs_delayed_ref_lock(struct btrfs_trans_handle *trans, 179c3e69d58SChris Mason struct btrfs_delayed_ref_head *head); 180c3e69d58SChris Mason int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans, 181c3e69d58SChris Mason struct list_head *cluster, u64 search_start); 18256bec294SChris Mason /* 18356bec294SChris Mason * a node might live in a head or a regular ref, this lets you 18456bec294SChris Mason * test for the proper type to use. 18556bec294SChris Mason */ 18656bec294SChris Mason static int btrfs_delayed_ref_is_head(struct btrfs_delayed_ref_node *node) 18756bec294SChris Mason { 1885d4f98a2SYan Zheng return node->is_head; 18956bec294SChris Mason } 19056bec294SChris Mason 19156bec294SChris Mason /* 19256bec294SChris Mason * helper functions to cast a node into its container 19356bec294SChris Mason */ 1945d4f98a2SYan Zheng static inline struct btrfs_delayed_tree_ref * 1955d4f98a2SYan Zheng btrfs_delayed_node_to_tree_ref(struct btrfs_delayed_ref_node *node) 19656bec294SChris Mason { 19756bec294SChris Mason WARN_ON(btrfs_delayed_ref_is_head(node)); 1985d4f98a2SYan Zheng return container_of(node, struct btrfs_delayed_tree_ref, node); 1995d4f98a2SYan Zheng } 20056bec294SChris Mason 2015d4f98a2SYan Zheng static inline struct btrfs_delayed_data_ref * 2025d4f98a2SYan Zheng btrfs_delayed_node_to_data_ref(struct btrfs_delayed_ref_node *node) 2035d4f98a2SYan Zheng { 2045d4f98a2SYan Zheng WARN_ON(btrfs_delayed_ref_is_head(node)); 2055d4f98a2SYan Zheng return container_of(node, struct btrfs_delayed_data_ref, node); 20656bec294SChris Mason } 20756bec294SChris Mason 20856bec294SChris Mason static inline struct btrfs_delayed_ref_head * 20956bec294SChris Mason btrfs_delayed_node_to_head(struct btrfs_delayed_ref_node *node) 21056bec294SChris Mason { 21156bec294SChris Mason WARN_ON(!btrfs_delayed_ref_is_head(node)); 21256bec294SChris Mason return container_of(node, struct btrfs_delayed_ref_head, node); 21356bec294SChris Mason } 21456bec294SChris Mason #endif 215