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v6.9.4
  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (C) 2008 Oracle.  All rights reserved.
  4 */
  5
  6#ifndef BTRFS_DELAYED_REF_H
  7#define BTRFS_DELAYED_REF_H
  8
  9#include <linux/types.h>
 10#include <linux/refcount.h>
 11#include <linux/list.h>
 12#include <linux/rbtree.h>
 13#include <linux/mutex.h>
 14#include <linux/spinlock.h>
 15#include <linux/slab.h>
 16#include <uapi/linux/btrfs_tree.h>
 17
 18struct btrfs_trans_handle;
 19struct btrfs_fs_info;
 20
 21/* these are the possible values of struct btrfs_delayed_ref_node->action */
 22enum btrfs_delayed_ref_action {
 23	/* Add one backref to the tree */
 24	BTRFS_ADD_DELAYED_REF = 1,
 25	/* Delete one backref from the tree */
 26	BTRFS_DROP_DELAYED_REF,
 27	/* Record a full extent allocation */
 28	BTRFS_ADD_DELAYED_EXTENT,
 29	/* Not changing ref count on head ref */
 30	BTRFS_UPDATE_DELAYED_HEAD,
 31} __packed;
 32
 33struct btrfs_delayed_ref_node {
 34	struct rb_node ref_node;
 35	/*
 36	 * If action is BTRFS_ADD_DELAYED_REF, also link this node to
 37	 * ref_head->ref_add_list, then we do not need to iterate the
 38	 * whole ref_head->ref_list to find BTRFS_ADD_DELAYED_REF nodes.
 39	 */
 40	struct list_head add_list;
 41
 42	/* the starting bytenr of the extent */
 43	u64 bytenr;
 44
 45	/* the size of the extent */
 46	u64 num_bytes;
 47
 48	/* seq number to keep track of insertion order */
 49	u64 seq;
 50
 51	/* ref count on this data structure */
 52	refcount_t refs;
 53
 54	/*
 55	 * how many refs is this entry adding or deleting.  For
 56	 * head refs, this may be a negative number because it is keeping
 57	 * track of the total mods done to the reference count.
 58	 * For individual refs, this will always be a positive number
 59	 *
 60	 * It may be more than one, since it is possible for a single
 61	 * parent to have more than one ref on an extent
 62	 */
 63	int ref_mod;
 64
 65	unsigned int action:8;
 66	unsigned int type:8;
 
 
 
 67};
 68
 69struct btrfs_delayed_extent_op {
 70	struct btrfs_disk_key key;
 71	u8 level;
 72	bool update_key;
 73	bool update_flags;
 
 74	u64 flags_to_set;
 75};
 76
 77/*
 78 * the head refs are used to hold a lock on a given extent, which allows us
 79 * to make sure that only one process is running the delayed refs
 80 * at a time for a single extent.  They also store the sum of all the
 81 * reference count modifications we've queued up.
 82 */
 83struct btrfs_delayed_ref_head {
 84	u64 bytenr;
 85	u64 num_bytes;
 86	/*
 87	 * For insertion into struct btrfs_delayed_ref_root::href_root.
 88	 * Keep it in the same cache line as 'bytenr' for more efficient
 89	 * searches in the rbtree.
 90	 */
 91	struct rb_node href_node;
 92	/*
 93	 * the mutex is held while running the refs, and it is also
 94	 * held when checking the sum of reference modifications.
 95	 */
 96	struct mutex mutex;
 97
 98	refcount_t refs;
 99
100	/* Protects 'ref_tree' and 'ref_add_list'. */
101	spinlock_t lock;
102	struct rb_root_cached ref_tree;
103	/* accumulate add BTRFS_ADD_DELAYED_REF nodes to this ref_add_list. */
104	struct list_head ref_add_list;
105
 
 
106	struct btrfs_delayed_extent_op *extent_op;
107
108	/*
109	 * This is used to track the final ref_mod from all the refs associated
110	 * with this head ref, this is not adjusted as delayed refs are run,
111	 * this is meant to track if we need to do the csum accounting or not.
112	 */
113	int total_ref_mod;
114
115	/*
116	 * This is the current outstanding mod references for this bytenr.  This
117	 * is used with lookup_extent_info to get an accurate reference count
118	 * for a bytenr, so it is adjusted as delayed refs are run so that any
119	 * on disk reference count + ref_mod is accurate.
120	 */
121	int ref_mod;
122
123	/*
124	 * The root that triggered the allocation when must_insert_reserved is
125	 * set to true.
126	 */
127	u64 owning_root;
128
129	/*
130	 * Track reserved bytes when setting must_insert_reserved.  On success
131	 * or cleanup, we will need to free the reservation.
132	 */
133	u64 reserved_bytes;
134
135	/*
136	 * when a new extent is allocated, it is just reserved in memory
137	 * The actual extent isn't inserted into the extent allocation tree
138	 * until the delayed ref is processed.  must_insert_reserved is
139	 * used to flag a delayed ref so the accounting can be updated
140	 * when a full insert is done.
141	 *
142	 * It is possible the extent will be freed before it is ever
143	 * inserted into the extent allocation tree.  In this case
144	 * we need to update the in ram accounting to properly reflect
145	 * the free has happened.
146	 */
147	bool must_insert_reserved;
148
149	bool is_data;
150	bool is_system;
151	bool processing;
152};
153
154struct btrfs_delayed_tree_ref {
155	struct btrfs_delayed_ref_node node;
156	u64 root;
157	u64 parent;
158	int level;
159};
160
161struct btrfs_delayed_data_ref {
162	struct btrfs_delayed_ref_node node;
163	u64 root;
164	u64 parent;
165	u64 objectid;
166	u64 offset;
167};
168
169enum btrfs_delayed_ref_flags {
170	/* Indicate that we are flushing delayed refs for the commit */
171	BTRFS_DELAYED_REFS_FLUSHING,
172};
173
174struct btrfs_delayed_ref_root {
175	/* head ref rbtree */
176	struct rb_root_cached href_root;
177
178	/* dirty extent records */
179	struct rb_root dirty_extent_root;
180
181	/* this spin lock protects the rbtree and the entries inside */
182	spinlock_t lock;
183
184	/* how many delayed ref updates we've queued, used by the
185	 * throttling code
186	 */
187	atomic_t num_entries;
188
189	/* total number of head nodes in tree */
190	unsigned long num_heads;
191
192	/* total number of head nodes ready for processing */
193	unsigned long num_heads_ready;
194
195	u64 pending_csums;
196
197	unsigned long flags;
198
199	u64 run_delayed_start;
200
201	/*
202	 * To make qgroup to skip given root.
203	 * This is for snapshot, as btrfs_qgroup_inherit() will manually
204	 * modify counters for snapshot and its source, so we should skip
205	 * the snapshot in new_root/old_roots or it will get calculated twice
206	 */
207	u64 qgroup_to_skip;
208};
209
210enum btrfs_ref_type {
211	BTRFS_REF_NOT_SET,
212	BTRFS_REF_DATA,
213	BTRFS_REF_METADATA,
214	BTRFS_REF_LAST,
215} __packed;
216
217struct btrfs_data_ref {
218	/* For EXTENT_DATA_REF */
219
220	/* Root which owns this data reference. */
221	u64 ref_root;
222
223	/* Inode which refers to this data extent */
224	u64 ino;
225
226	/*
227	 * file_offset - extent_offset
228	 *
229	 * file_offset is the key.offset of the EXTENT_DATA key.
230	 * extent_offset is btrfs_file_extent_offset() of the EXTENT_DATA data.
231	 */
232	u64 offset;
233};
234
235struct btrfs_tree_ref {
236	/*
237	 * Level of this tree block
238	 *
239	 * Shared for skinny (TREE_BLOCK_REF) and normal tree ref.
240	 */
241	int level;
242
243	/*
244	 * Root which owns this tree block reference.
245	 *
246	 * For TREE_BLOCK_REF (skinny metadata, either inline or keyed)
247	 */
248	u64 ref_root;
249
250	/* For non-skinny metadata, no special member needed */
251};
252
253struct btrfs_ref {
254	enum btrfs_ref_type type;
255	enum btrfs_delayed_ref_action action;
256
257	/*
258	 * Whether this extent should go through qgroup record.
259	 *
260	 * Normally false, but for certain cases like delayed subtree scan,
261	 * setting this flag can hugely reduce qgroup overhead.
262	 */
263	bool skip_qgroup;
264
265#ifdef CONFIG_BTRFS_FS_REF_VERIFY
266	/* Through which root is this modification. */
 
 
 
 
 
 
 
 
267	u64 real_root;
268#endif
269	u64 bytenr;
270	u64 len;
271	u64 owning_root;
272
273	/* Bytenr of the parent tree block */
274	u64 parent;
275	union {
276		struct btrfs_data_ref data_ref;
277		struct btrfs_tree_ref tree_ref;
278	};
279};
280
281extern struct kmem_cache *btrfs_delayed_ref_head_cachep;
282extern struct kmem_cache *btrfs_delayed_tree_ref_cachep;
283extern struct kmem_cache *btrfs_delayed_data_ref_cachep;
284extern struct kmem_cache *btrfs_delayed_extent_op_cachep;
285
286int __init btrfs_delayed_ref_init(void);
287void __cold btrfs_delayed_ref_exit(void);
288
289static inline u64 btrfs_calc_delayed_ref_bytes(const struct btrfs_fs_info *fs_info,
290					       int num_delayed_refs)
291{
292	u64 num_bytes;
293
294	num_bytes = btrfs_calc_insert_metadata_size(fs_info, num_delayed_refs);
295
296	/*
297	 * We have to check the mount option here because we could be enabling
298	 * the free space tree for the first time and don't have the compat_ro
299	 * option set yet.
300	 *
301	 * We need extra reservations if we have the free space tree because
302	 * we'll have to modify that tree as well.
303	 */
304	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE))
305		num_bytes *= 2;
306
307	return num_bytes;
308}
309
310static inline u64 btrfs_calc_delayed_ref_csum_bytes(const struct btrfs_fs_info *fs_info,
311						    int num_csum_items)
312{
313	/*
314	 * Deleting csum items does not result in new nodes/leaves and does not
315	 * require changing the free space tree, only the csum tree, so this is
316	 * all we need.
317	 */
318	return btrfs_calc_metadata_size(fs_info, num_csum_items);
319}
320
321void btrfs_init_generic_ref(struct btrfs_ref *generic_ref, int action, u64 bytenr,
322			    u64 len, u64 parent, u64 owning_root);
323void btrfs_init_tree_ref(struct btrfs_ref *generic_ref, int level, u64 root,
324			 u64 mod_root, bool skip_qgroup);
325void btrfs_init_data_ref(struct btrfs_ref *generic_ref, u64 ref_root, u64 ino,
326			 u64 offset, u64 mod_root, bool skip_qgroup);
 
 
 
 
 
327
328static inline struct btrfs_delayed_extent_op *
329btrfs_alloc_delayed_extent_op(void)
330{
331	return kmem_cache_alloc(btrfs_delayed_extent_op_cachep, GFP_NOFS);
332}
333
334static inline void
335btrfs_free_delayed_extent_op(struct btrfs_delayed_extent_op *op)
336{
337	if (op)
338		kmem_cache_free(btrfs_delayed_extent_op_cachep, op);
339}
340
341void btrfs_put_delayed_ref(struct btrfs_delayed_ref_node *ref);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
342
343static inline u64 btrfs_ref_head_to_space_flags(
344				struct btrfs_delayed_ref_head *head_ref)
345{
346	if (head_ref->is_data)
347		return BTRFS_BLOCK_GROUP_DATA;
348	else if (head_ref->is_system)
349		return BTRFS_BLOCK_GROUP_SYSTEM;
350	return BTRFS_BLOCK_GROUP_METADATA;
351}
352
353static inline void btrfs_put_delayed_ref_head(struct btrfs_delayed_ref_head *head)
354{
355	if (refcount_dec_and_test(&head->refs))
356		kmem_cache_free(btrfs_delayed_ref_head_cachep, head);
357}
358
359int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
360			       struct btrfs_ref *generic_ref,
361			       struct btrfs_delayed_extent_op *extent_op);
362int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans,
363			       struct btrfs_ref *generic_ref,
364			       u64 reserved);
365int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans,
366				u64 bytenr, u64 num_bytes,
367				struct btrfs_delayed_extent_op *extent_op);
368void btrfs_merge_delayed_refs(struct btrfs_fs_info *fs_info,
369			      struct btrfs_delayed_ref_root *delayed_refs,
370			      struct btrfs_delayed_ref_head *head);
371
372struct btrfs_delayed_ref_head *
373btrfs_find_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
374			    u64 bytenr);
375int btrfs_delayed_ref_lock(struct btrfs_delayed_ref_root *delayed_refs,
376			   struct btrfs_delayed_ref_head *head);
377static inline void btrfs_delayed_ref_unlock(struct btrfs_delayed_ref_head *head)
378{
379	mutex_unlock(&head->mutex);
380}
381void btrfs_delete_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
382			   struct btrfs_delayed_ref_head *head);
383
384struct btrfs_delayed_ref_head *btrfs_select_ref_head(
385		struct btrfs_delayed_ref_root *delayed_refs);
386
387int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq);
388
389void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr_refs, int nr_csums);
390void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans);
391void btrfs_inc_delayed_refs_rsv_bg_inserts(struct btrfs_fs_info *fs_info);
392void btrfs_dec_delayed_refs_rsv_bg_inserts(struct btrfs_fs_info *fs_info);
393void btrfs_inc_delayed_refs_rsv_bg_updates(struct btrfs_fs_info *fs_info);
394void btrfs_dec_delayed_refs_rsv_bg_updates(struct btrfs_fs_info *fs_info);
395int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
396				  enum btrfs_reserve_flush_enum flush);
397void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
 
398				       u64 num_bytes);
 
399bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info);
400
401/*
402 * helper functions to cast a node into its container
403 */
404static inline struct btrfs_delayed_tree_ref *
405btrfs_delayed_node_to_tree_ref(struct btrfs_delayed_ref_node *node)
406{
407	return container_of(node, struct btrfs_delayed_tree_ref, node);
408}
409
410static inline struct btrfs_delayed_data_ref *
411btrfs_delayed_node_to_data_ref(struct btrfs_delayed_ref_node *node)
412{
413	return container_of(node, struct btrfs_delayed_data_ref, node);
414}
415
416#endif
v5.14.15
  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (C) 2008 Oracle.  All rights reserved.
  4 */
  5
  6#ifndef BTRFS_DELAYED_REF_H
  7#define BTRFS_DELAYED_REF_H
  8
 
  9#include <linux/refcount.h>
 
 
 
 
 
 
 
 
 
 10
 11/* these are the possible values of struct btrfs_delayed_ref_node->action */
 12#define BTRFS_ADD_DELAYED_REF    1 /* add one backref to the tree */
 13#define BTRFS_DROP_DELAYED_REF   2 /* delete one backref from the tree */
 14#define BTRFS_ADD_DELAYED_EXTENT 3 /* record a full extent allocation */
 15#define BTRFS_UPDATE_DELAYED_HEAD 4 /* not changing ref count on head ref */
 
 
 
 
 
 
 16
 17struct btrfs_delayed_ref_node {
 18	struct rb_node ref_node;
 19	/*
 20	 * If action is BTRFS_ADD_DELAYED_REF, also link this node to
 21	 * ref_head->ref_add_list, then we do not need to iterate the
 22	 * whole ref_head->ref_list to find BTRFS_ADD_DELAYED_REF nodes.
 23	 */
 24	struct list_head add_list;
 25
 26	/* the starting bytenr of the extent */
 27	u64 bytenr;
 28
 29	/* the size of the extent */
 30	u64 num_bytes;
 31
 32	/* seq number to keep track of insertion order */
 33	u64 seq;
 34
 35	/* ref count on this data structure */
 36	refcount_t refs;
 37
 38	/*
 39	 * how many refs is this entry adding or deleting.  For
 40	 * head refs, this may be a negative number because it is keeping
 41	 * track of the total mods done to the reference count.
 42	 * For individual refs, this will always be a positive number
 43	 *
 44	 * It may be more than one, since it is possible for a single
 45	 * parent to have more than one ref on an extent
 46	 */
 47	int ref_mod;
 48
 49	unsigned int action:8;
 50	unsigned int type:8;
 51	/* is this node still in the rbtree? */
 52	unsigned int is_head:1;
 53	unsigned int in_tree:1;
 54};
 55
 56struct btrfs_delayed_extent_op {
 57	struct btrfs_disk_key key;
 58	u8 level;
 59	bool update_key;
 60	bool update_flags;
 61	bool is_data;
 62	u64 flags_to_set;
 63};
 64
 65/*
 66 * the head refs are used to hold a lock on a given extent, which allows us
 67 * to make sure that only one process is running the delayed refs
 68 * at a time for a single extent.  They also store the sum of all the
 69 * reference count modifications we've queued up.
 70 */
 71struct btrfs_delayed_ref_head {
 72	u64 bytenr;
 73	u64 num_bytes;
 74	refcount_t refs;
 
 
 
 
 
 75	/*
 76	 * the mutex is held while running the refs, and it is also
 77	 * held when checking the sum of reference modifications.
 78	 */
 79	struct mutex mutex;
 80
 
 
 
 81	spinlock_t lock;
 82	struct rb_root_cached ref_tree;
 83	/* accumulate add BTRFS_ADD_DELAYED_REF nodes to this ref_add_list. */
 84	struct list_head ref_add_list;
 85
 86	struct rb_node href_node;
 87
 88	struct btrfs_delayed_extent_op *extent_op;
 89
 90	/*
 91	 * This is used to track the final ref_mod from all the refs associated
 92	 * with this head ref, this is not adjusted as delayed refs are run,
 93	 * this is meant to track if we need to do the csum accounting or not.
 94	 */
 95	int total_ref_mod;
 96
 97	/*
 98	 * This is the current outstanding mod references for this bytenr.  This
 99	 * is used with lookup_extent_info to get an accurate reference count
100	 * for a bytenr, so it is adjusted as delayed refs are run so that any
101	 * on disk reference count + ref_mod is accurate.
102	 */
103	int ref_mod;
104
105	/*
 
 
 
 
 
 
 
 
 
 
 
 
106	 * when a new extent is allocated, it is just reserved in memory
107	 * The actual extent isn't inserted into the extent allocation tree
108	 * until the delayed ref is processed.  must_insert_reserved is
109	 * used to flag a delayed ref so the accounting can be updated
110	 * when a full insert is done.
111	 *
112	 * It is possible the extent will be freed before it is ever
113	 * inserted into the extent allocation tree.  In this case
114	 * we need to update the in ram accounting to properly reflect
115	 * the free has happened.
116	 */
117	unsigned int must_insert_reserved:1;
118	unsigned int is_data:1;
119	unsigned int is_system:1;
120	unsigned int processing:1;
 
121};
122
123struct btrfs_delayed_tree_ref {
124	struct btrfs_delayed_ref_node node;
125	u64 root;
126	u64 parent;
127	int level;
128};
129
130struct btrfs_delayed_data_ref {
131	struct btrfs_delayed_ref_node node;
132	u64 root;
133	u64 parent;
134	u64 objectid;
135	u64 offset;
136};
137
138enum btrfs_delayed_ref_flags {
139	/* Indicate that we are flushing delayed refs for the commit */
140	BTRFS_DELAYED_REFS_FLUSHING,
141};
142
143struct btrfs_delayed_ref_root {
144	/* head ref rbtree */
145	struct rb_root_cached href_root;
146
147	/* dirty extent records */
148	struct rb_root dirty_extent_root;
149
150	/* this spin lock protects the rbtree and the entries inside */
151	spinlock_t lock;
152
153	/* how many delayed ref updates we've queued, used by the
154	 * throttling code
155	 */
156	atomic_t num_entries;
157
158	/* total number of head nodes in tree */
159	unsigned long num_heads;
160
161	/* total number of head nodes ready for processing */
162	unsigned long num_heads_ready;
163
164	u64 pending_csums;
165
166	unsigned long flags;
167
168	u64 run_delayed_start;
169
170	/*
171	 * To make qgroup to skip given root.
172	 * This is for snapshot, as btrfs_qgroup_inherit() will manually
173	 * modify counters for snapshot and its source, so we should skip
174	 * the snapshot in new_root/old_roots or it will get calculated twice
175	 */
176	u64 qgroup_to_skip;
177};
178
179enum btrfs_ref_type {
180	BTRFS_REF_NOT_SET,
181	BTRFS_REF_DATA,
182	BTRFS_REF_METADATA,
183	BTRFS_REF_LAST,
184};
185
186struct btrfs_data_ref {
187	/* For EXTENT_DATA_REF */
188
189	/* Root which refers to this data extent */
190	u64 ref_root;
191
192	/* Inode which refers to this data extent */
193	u64 ino;
194
195	/*
196	 * file_offset - extent_offset
197	 *
198	 * file_offset is the key.offset of the EXTENT_DATA key.
199	 * extent_offset is btrfs_file_extent_offset() of the EXTENT_DATA data.
200	 */
201	u64 offset;
202};
203
204struct btrfs_tree_ref {
205	/*
206	 * Level of this tree block
207	 *
208	 * Shared for skinny (TREE_BLOCK_REF) and normal tree ref.
209	 */
210	int level;
211
212	/*
213	 * Root which refers to this tree block.
214	 *
215	 * For TREE_BLOCK_REF (skinny metadata, either inline or keyed)
216	 */
217	u64 root;
218
219	/* For non-skinny metadata, no special member needed */
220};
221
222struct btrfs_ref {
223	enum btrfs_ref_type type;
224	int action;
225
226	/*
227	 * Whether this extent should go through qgroup record.
228	 *
229	 * Normally false, but for certain cases like delayed subtree scan,
230	 * setting this flag can hugely reduce qgroup overhead.
231	 */
232	bool skip_qgroup;
233
234	/*
235	 * Optional. For which root is this modification.
236	 * Mostly used for qgroup optimization.
237	 *
238	 * When unset, data/tree ref init code will populate it.
239	 * In certain cases, we're modifying reference for a different root.
240	 * E.g. COW fs tree blocks for balance.
241	 * In that case, tree_ref::root will be fs tree, but we're doing this
242	 * for reloc tree, then we should set @real_root to reloc tree.
243	 */
244	u64 real_root;
 
245	u64 bytenr;
246	u64 len;
 
247
248	/* Bytenr of the parent tree block */
249	u64 parent;
250	union {
251		struct btrfs_data_ref data_ref;
252		struct btrfs_tree_ref tree_ref;
253	};
254};
255
256extern struct kmem_cache *btrfs_delayed_ref_head_cachep;
257extern struct kmem_cache *btrfs_delayed_tree_ref_cachep;
258extern struct kmem_cache *btrfs_delayed_data_ref_cachep;
259extern struct kmem_cache *btrfs_delayed_extent_op_cachep;
260
261int __init btrfs_delayed_ref_init(void);
262void __cold btrfs_delayed_ref_exit(void);
263
264static inline void btrfs_init_generic_ref(struct btrfs_ref *generic_ref,
265				int action, u64 bytenr, u64 len, u64 parent)
266{
267	generic_ref->action = action;
268	generic_ref->bytenr = bytenr;
269	generic_ref->len = len;
270	generic_ref->parent = parent;
 
 
 
 
 
 
 
 
 
 
 
 
271}
272
273static inline void btrfs_init_tree_ref(struct btrfs_ref *generic_ref,
274				int level, u64 root)
275{
276	/* If @real_root not set, use @root as fallback */
277	if (!generic_ref->real_root)
278		generic_ref->real_root = root;
279	generic_ref->tree_ref.level = level;
280	generic_ref->tree_ref.root = root;
281	generic_ref->type = BTRFS_REF_METADATA;
282}
283
284static inline void btrfs_init_data_ref(struct btrfs_ref *generic_ref,
285				u64 ref_root, u64 ino, u64 offset)
286{
287	/* If @real_root not set, use @root as fallback */
288	if (!generic_ref->real_root)
289		generic_ref->real_root = ref_root;
290	generic_ref->data_ref.ref_root = ref_root;
291	generic_ref->data_ref.ino = ino;
292	generic_ref->data_ref.offset = offset;
293	generic_ref->type = BTRFS_REF_DATA;
294}
295
296static inline struct btrfs_delayed_extent_op *
297btrfs_alloc_delayed_extent_op(void)
298{
299	return kmem_cache_alloc(btrfs_delayed_extent_op_cachep, GFP_NOFS);
300}
301
302static inline void
303btrfs_free_delayed_extent_op(struct btrfs_delayed_extent_op *op)
304{
305	if (op)
306		kmem_cache_free(btrfs_delayed_extent_op_cachep, op);
307}
308
309static inline void btrfs_put_delayed_ref(struct btrfs_delayed_ref_node *ref)
310{
311	WARN_ON(refcount_read(&ref->refs) == 0);
312	if (refcount_dec_and_test(&ref->refs)) {
313		WARN_ON(ref->in_tree);
314		switch (ref->type) {
315		case BTRFS_TREE_BLOCK_REF_KEY:
316		case BTRFS_SHARED_BLOCK_REF_KEY:
317			kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
318			break;
319		case BTRFS_EXTENT_DATA_REF_KEY:
320		case BTRFS_SHARED_DATA_REF_KEY:
321			kmem_cache_free(btrfs_delayed_data_ref_cachep, ref);
322			break;
323		default:
324			BUG();
325		}
326	}
327}
328
329static inline u64 btrfs_ref_head_to_space_flags(
330				struct btrfs_delayed_ref_head *head_ref)
331{
332	if (head_ref->is_data)
333		return BTRFS_BLOCK_GROUP_DATA;
334	else if (head_ref->is_system)
335		return BTRFS_BLOCK_GROUP_SYSTEM;
336	return BTRFS_BLOCK_GROUP_METADATA;
337}
338
339static inline void btrfs_put_delayed_ref_head(struct btrfs_delayed_ref_head *head)
340{
341	if (refcount_dec_and_test(&head->refs))
342		kmem_cache_free(btrfs_delayed_ref_head_cachep, head);
343}
344
345int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
346			       struct btrfs_ref *generic_ref,
347			       struct btrfs_delayed_extent_op *extent_op);
348int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans,
349			       struct btrfs_ref *generic_ref,
350			       u64 reserved);
351int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans,
352				u64 bytenr, u64 num_bytes,
353				struct btrfs_delayed_extent_op *extent_op);
354void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans,
355			      struct btrfs_delayed_ref_root *delayed_refs,
356			      struct btrfs_delayed_ref_head *head);
357
358struct btrfs_delayed_ref_head *
359btrfs_find_delayed_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
360			    u64 bytenr);
361int btrfs_delayed_ref_lock(struct btrfs_delayed_ref_root *delayed_refs,
362			   struct btrfs_delayed_ref_head *head);
363static inline void btrfs_delayed_ref_unlock(struct btrfs_delayed_ref_head *head)
364{
365	mutex_unlock(&head->mutex);
366}
367void btrfs_delete_ref_head(struct btrfs_delayed_ref_root *delayed_refs,
368			   struct btrfs_delayed_ref_head *head);
369
370struct btrfs_delayed_ref_head *btrfs_select_ref_head(
371		struct btrfs_delayed_ref_root *delayed_refs);
372
373int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, u64 seq);
374
375void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr);
376void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans);
 
 
 
 
377int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
378				  enum btrfs_reserve_flush_enum flush);
379void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
380				       struct btrfs_block_rsv *src,
381				       u64 num_bytes);
382int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans);
383bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info);
384
385/*
386 * helper functions to cast a node into its container
387 */
388static inline struct btrfs_delayed_tree_ref *
389btrfs_delayed_node_to_tree_ref(struct btrfs_delayed_ref_node *node)
390{
391	return container_of(node, struct btrfs_delayed_tree_ref, node);
392}
393
394static inline struct btrfs_delayed_data_ref *
395btrfs_delayed_node_to_data_ref(struct btrfs_delayed_ref_node *node)
396{
397	return container_of(node, struct btrfs_delayed_data_ref, node);
398}
399
400#endif