1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (c) 2018 Red Hat, Inc.
4 * All rights reserved.
5 */
6
7#ifndef __LIBXFS_AG_H
8#define __LIBXFS_AG_H 1
9
10struct xfs_mount;
11struct xfs_trans;
12struct xfs_perag;
13
14/*
15 * Per-ag infrastructure
16 */
17
18/* per-AG block reservation data structures*/
19struct xfs_ag_resv {
20	/* number of blocks originally reserved here */
21	xfs_extlen_t			ar_orig_reserved;
22	/* number of blocks reserved here */
23	xfs_extlen_t			ar_reserved;
24	/* number of blocks originally asked for */
25	xfs_extlen_t			ar_asked;
26};
27
28/*
29 * Per-ag incore structure, copies of information in agf and agi, to improve the
30 * performance of allocation group selection.
31 */
32struct xfs_perag {
33	struct xfs_mount *pag_mount;	/* owner filesystem */
34	xfs_agnumber_t	pag_agno;	/* AG this structure belongs to */
35	atomic_t	pag_ref;	/* passive reference count */
36	atomic_t	pag_active_ref;	/* active reference count */
37	wait_queue_head_t pag_active_wq;/* woken active_ref falls to zero */
38	unsigned long	pag_opstate;
39	uint8_t		pagf_bno_level;	/* # of levels in bno btree */
40	uint8_t		pagf_cnt_level;	/* # of levels in cnt btree */
41	uint8_t		pagf_rmap_level;/* # of levels in rmap btree */
42	uint32_t	pagf_flcount;	/* count of blocks in freelist */
43	xfs_extlen_t	pagf_freeblks;	/* total free blocks */
44	xfs_extlen_t	pagf_longest;	/* longest free space */
45	uint32_t	pagf_btreeblks;	/* # of blocks held in AGF btrees */
46	xfs_agino_t	pagi_freecount;	/* number of free inodes */
47	xfs_agino_t	pagi_count;	/* number of allocated inodes */
48
49	/*
50	 * Inode allocation search lookup optimisation.
51	 * If the pagino matches, the search for new inodes
52	 * doesn't need to search the near ones again straight away
53	 */
54	xfs_agino_t	pagl_pagino;
55	xfs_agino_t	pagl_leftrec;
56	xfs_agino_t	pagl_rightrec;
57
58	int		pagb_count;	/* pagb slots in use */
59	uint8_t		pagf_refcount_level; /* recount btree height */
60
61	/* Blocks reserved for all kinds of metadata. */
62	struct xfs_ag_resv	pag_meta_resv;
63	/* Blocks reserved for the reverse mapping btree. */
64	struct xfs_ag_resv	pag_rmapbt_resv;
65
66	/* for rcu-safe freeing */
67	struct rcu_head	rcu_head;
68
69	/* Precalculated geometry info */
70	xfs_agblock_t		block_count;
71	xfs_agblock_t		min_block;
72	xfs_agino_t		agino_min;
73	xfs_agino_t		agino_max;
74
75#ifdef __KERNEL__
76	/* -- kernel only structures below this line -- */
77
78	/*
79	 * Bitsets of per-ag metadata that have been checked and/or are sick.
80	 * Callers should hold pag_state_lock before accessing this field.
81	 */
82	uint16_t	pag_checked;
83	uint16_t	pag_sick;
84
85#ifdef CONFIG_XFS_ONLINE_REPAIR
86	/*
87	 * Alternate btree heights so that online repair won't trip the write
88	 * verifiers while rebuilding the AG btrees.
89	 */
90	uint8_t		pagf_repair_bno_level;
91	uint8_t		pagf_repair_cnt_level;
92	uint8_t		pagf_repair_refcount_level;
93	uint8_t		pagf_repair_rmap_level;
94#endif
95
96	spinlock_t	pag_state_lock;
97
98	spinlock_t	pagb_lock;	/* lock for pagb_tree */
99	struct rb_root	pagb_tree;	/* ordered tree of busy extents */
100	unsigned int	pagb_gen;	/* generation count for pagb_tree */
101	wait_queue_head_t pagb_wait;	/* woken when pagb_gen changes */
102
103	atomic_t        pagf_fstrms;    /* # of filestreams active in this AG */
104
105	spinlock_t	pag_ici_lock;	/* incore inode cache lock */
106	struct radix_tree_root pag_ici_root;	/* incore inode cache root */
107	int		pag_ici_reclaimable;	/* reclaimable inodes */
108	unsigned long	pag_ici_reclaim_cursor;	/* reclaim restart point */
109
110	struct xfs_buf_cache	pag_bcache;
111
112	/* background prealloc block trimming */
113	struct delayed_work	pag_blockgc_work;
114
115	/*
116	 * We use xfs_drain to track the number of deferred log intent items
117	 * that have been queued (but not yet processed) so that waiters (e.g.
118	 * scrub) will not lock resources when other threads are in the middle
119	 * of processing a chain of intent items only to find momentary
120	 * inconsistencies.
121	 */
122	struct xfs_defer_drain	pag_intents_drain;
123
124	/* Hook to feed rmapbt updates to an active online repair. */
125	struct xfs_hooks	pag_rmap_update_hooks;
126#endif /* __KERNEL__ */
127};
128
129/*
130 * Per-AG operational state. These are atomic flag bits.
131 */
132#define XFS_AGSTATE_AGF_INIT		0
133#define XFS_AGSTATE_AGI_INIT		1
134#define XFS_AGSTATE_PREFERS_METADATA	2
135#define XFS_AGSTATE_ALLOWS_INODES	3
136#define XFS_AGSTATE_AGFL_NEEDS_RESET	4
137
138#define __XFS_AG_OPSTATE(name, NAME) \
139static inline bool xfs_perag_ ## name (struct xfs_perag *pag) \
140{ \
141	return test_bit(XFS_AGSTATE_ ## NAME, &pag->pag_opstate); \
142}
143
144__XFS_AG_OPSTATE(initialised_agf, AGF_INIT)
145__XFS_AG_OPSTATE(initialised_agi, AGI_INIT)
146__XFS_AG_OPSTATE(prefers_metadata, PREFERS_METADATA)
147__XFS_AG_OPSTATE(allows_inodes, ALLOWS_INODES)
148__XFS_AG_OPSTATE(agfl_needs_reset, AGFL_NEEDS_RESET)
149
150void xfs_free_unused_perag_range(struct xfs_mount *mp, xfs_agnumber_t agstart,
151			xfs_agnumber_t agend);
152int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
153			xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
154int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
155void xfs_free_perag(struct xfs_mount *mp);
156
157/* Passive AG references */
158struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
159struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
160		unsigned int tag);
161struct xfs_perag *xfs_perag_hold(struct xfs_perag *pag);
162void xfs_perag_put(struct xfs_perag *pag);
163
164/* Active AG references */
165struct xfs_perag *xfs_perag_grab(struct xfs_mount *, xfs_agnumber_t);
166struct xfs_perag *xfs_perag_grab_tag(struct xfs_mount *, xfs_agnumber_t,
167				   int tag);
168void xfs_perag_rele(struct xfs_perag *pag);
169
170/*
171 * Per-ag geometry infomation and validation
172 */
173xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
174void xfs_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
175		xfs_agino_t *first, xfs_agino_t *last);
176
177static inline bool
178xfs_verify_agbno(struct xfs_perag *pag, xfs_agblock_t agbno)
179{
180	if (agbno >= pag->block_count)
181		return false;
182	if (agbno <= pag->min_block)
183		return false;
184	return true;
185}
186
187static inline bool
188xfs_verify_agbext(
189	struct xfs_perag	*pag,
190	xfs_agblock_t		agbno,
191	xfs_agblock_t		len)
192{
193	if (agbno + len <= agbno)
194		return false;
195
196	if (!xfs_verify_agbno(pag, agbno))
197		return false;
198
199	return xfs_verify_agbno(pag, agbno + len - 1);
200}
201
202/*
203 * Verify that an AG inode number pointer neither points outside the AG
204 * nor points at static metadata.
205 */
206static inline bool
207xfs_verify_agino(struct xfs_perag *pag, xfs_agino_t agino)
208{
209	if (agino < pag->agino_min)
210		return false;
211	if (agino > pag->agino_max)
212		return false;
213	return true;
214}
215
216/*
217 * Verify that an AG inode number pointer neither points outside the AG
218 * nor points at static metadata, or is NULLAGINO.
219 */
220static inline bool
221xfs_verify_agino_or_null(struct xfs_perag *pag, xfs_agino_t agino)
222{
223	if (agino == NULLAGINO)
224		return true;
225	return xfs_verify_agino(pag, agino);
226}
227
228static inline bool
229xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
230{
231	return mp->m_sb.sb_logstart > 0 &&
232	       agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
233}
234
235/*
236 * Perag iteration APIs
237 */
238static inline struct xfs_perag *
239xfs_perag_next(
240	struct xfs_perag	*pag,
241	xfs_agnumber_t		*agno,
242	xfs_agnumber_t		end_agno)
243{
244	struct xfs_mount	*mp = pag->pag_mount;
245
246	*agno = pag->pag_agno + 1;
247	xfs_perag_rele(pag);
248	while (*agno <= end_agno) {
249		pag = xfs_perag_grab(mp, *agno);
250		if (pag)
251			return pag;
252		(*agno)++;
253	}
254	return NULL;
255}
256
257#define for_each_perag_range(mp, agno, end_agno, pag) \
258	for ((pag) = xfs_perag_grab((mp), (agno)); \
259		(pag) != NULL; \
260		(pag) = xfs_perag_next((pag), &(agno), (end_agno)))
261
262#define for_each_perag_from(mp, agno, pag) \
263	for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
264
265#define for_each_perag(mp, agno, pag) \
266	(agno) = 0; \
267	for_each_perag_from((mp), (agno), (pag))
268
269#define for_each_perag_tag(mp, agno, pag, tag) \
270	for ((agno) = 0, (pag) = xfs_perag_grab_tag((mp), 0, (tag)); \
271		(pag) != NULL; \
272		(agno) = (pag)->pag_agno + 1, \
273		xfs_perag_rele(pag), \
274		(pag) = xfs_perag_grab_tag((mp), (agno), (tag)))
275
276static inline struct xfs_perag *
277xfs_perag_next_wrap(
278	struct xfs_perag	*pag,
279	xfs_agnumber_t		*agno,
280	xfs_agnumber_t		stop_agno,
281	xfs_agnumber_t		restart_agno,
282	xfs_agnumber_t		wrap_agno)
283{
284	struct xfs_mount	*mp = pag->pag_mount;
285
286	*agno = pag->pag_agno + 1;
287	xfs_perag_rele(pag);
288	while (*agno != stop_agno) {
289		if (*agno >= wrap_agno) {
290			if (restart_agno >= stop_agno)
291				break;
292			*agno = restart_agno;
293		}
294
295		pag = xfs_perag_grab(mp, *agno);
296		if (pag)
297			return pag;
298		(*agno)++;
299	}
300	return NULL;
301}
302
303/*
304 * Iterate all AGs from start_agno through wrap_agno, then restart_agno through
305 * (start_agno - 1).
306 */
307#define for_each_perag_wrap_range(mp, start_agno, restart_agno, wrap_agno, agno, pag) \
308	for ((agno) = (start_agno), (pag) = xfs_perag_grab((mp), (agno)); \
309		(pag) != NULL; \
310		(pag) = xfs_perag_next_wrap((pag), &(agno), (start_agno), \
311				(restart_agno), (wrap_agno)))
312/*
313 * Iterate all AGs from start_agno through wrap_agno, then 0 through
314 * (start_agno - 1).
315 */
316#define for_each_perag_wrap_at(mp, start_agno, wrap_agno, agno, pag) \
317	for_each_perag_wrap_range((mp), (start_agno), 0, (wrap_agno), (agno), (pag))
318
319/*
320 * Iterate all AGs from start_agno through to the end of the filesystem, then 0
321 * through (start_agno - 1).
322 */
323#define for_each_perag_wrap(mp, start_agno, agno, pag) \
324	for_each_perag_wrap_at((mp), (start_agno), (mp)->m_sb.sb_agcount, \
325				(agno), (pag))
326
327
328struct aghdr_init_data {
329	/* per ag data */
330	xfs_agblock_t		agno;		/* ag to init */
331	xfs_extlen_t		agsize;		/* new AG size */
332	struct list_head	buffer_list;	/* buffer writeback list */
333	xfs_rfsblock_t		nfree;		/* cumulative new free space */
334
335	/* per header data */
336	xfs_daddr_t		daddr;		/* header location */
337	size_t			numblks;	/* size of header */
338	const struct xfs_btree_ops *bc_ops;	/* btree ops */
339};
340
341int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
342int xfs_ag_shrink_space(struct xfs_perag *pag, struct xfs_trans **tpp,
343			xfs_extlen_t delta);
344int xfs_ag_extend_space(struct xfs_perag *pag, struct xfs_trans *tp,
345			xfs_extlen_t len);
346int xfs_ag_get_geometry(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
347
348#endif /* __LIBXFS_AG_H */
349