xref: /linux/fs/xfs/libxfs/xfs_ag.h (revision c4101e55974cc7d835fbd2d8e01553a3f61e9e75)
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 
10 struct xfs_mount;
11 struct xfs_trans;
12 struct xfs_perag;
13 
14 /*
15  * Per-ag infrastructure
16  */
17 
18 /* per-AG block reservation data structures*/
19 struct 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  */
32 struct 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_levels[XFS_BTNUM_AGF];
40 					/* # of levels in bno & cnt btree */
41 	uint32_t	pagf_flcount;	/* count of blocks in freelist */
42 	xfs_extlen_t	pagf_freeblks;	/* total free blocks */
43 	xfs_extlen_t	pagf_longest;	/* longest free space */
44 	uint32_t	pagf_btreeblks;	/* # of blocks held in AGF btrees */
45 	xfs_agino_t	pagi_freecount;	/* number of free inodes */
46 	xfs_agino_t	pagi_count;	/* number of allocated inodes */
47 
48 	/*
49 	 * Inode allocation search lookup optimisation.
50 	 * If the pagino matches, the search for new inodes
51 	 * doesn't need to search the near ones again straight away
52 	 */
53 	xfs_agino_t	pagl_pagino;
54 	xfs_agino_t	pagl_leftrec;
55 	xfs_agino_t	pagl_rightrec;
56 
57 	int		pagb_count;	/* pagb slots in use */
58 	uint8_t		pagf_refcount_level; /* recount btree height */
59 
60 	/* Blocks reserved for all kinds of metadata. */
61 	struct xfs_ag_resv	pag_meta_resv;
62 	/* Blocks reserved for the reverse mapping btree. */
63 	struct xfs_ag_resv	pag_rmapbt_resv;
64 
65 	/* for rcu-safe freeing */
66 	struct rcu_head	rcu_head;
67 
68 	/* Precalculated geometry info */
69 	xfs_agblock_t		block_count;
70 	xfs_agblock_t		min_block;
71 	xfs_agino_t		agino_min;
72 	xfs_agino_t		agino_max;
73 
74 #ifdef __KERNEL__
75 	/* -- kernel only structures below this line -- */
76 
77 	/*
78 	 * Bitsets of per-ag metadata that have been checked and/or are sick.
79 	 * Callers should hold pag_state_lock before accessing this field.
80 	 */
81 	uint16_t	pag_checked;
82 	uint16_t	pag_sick;
83 
84 #ifdef CONFIG_XFS_ONLINE_REPAIR
85 	/*
86 	 * Alternate btree heights so that online repair won't trip the write
87 	 * verifiers while rebuilding the AG btrees.
88 	 */
89 	uint8_t		pagf_repair_levels[XFS_BTNUM_AGF];
90 	uint8_t		pagf_repair_refcount_level;
91 #endif
92 
93 	spinlock_t	pag_state_lock;
94 
95 	spinlock_t	pagb_lock;	/* lock for pagb_tree */
96 	struct rb_root	pagb_tree;	/* ordered tree of busy extents */
97 	unsigned int	pagb_gen;	/* generation count for pagb_tree */
98 	wait_queue_head_t pagb_wait;	/* woken when pagb_gen changes */
99 
100 	atomic_t        pagf_fstrms;    /* # of filestreams active in this AG */
101 
102 	spinlock_t	pag_ici_lock;	/* incore inode cache lock */
103 	struct radix_tree_root pag_ici_root;	/* incore inode cache root */
104 	int		pag_ici_reclaimable;	/* reclaimable inodes */
105 	unsigned long	pag_ici_reclaim_cursor;	/* reclaim restart point */
106 
107 	/* buffer cache index */
108 	spinlock_t	pag_buf_lock;	/* lock for pag_buf_hash */
109 	struct rhashtable pag_buf_hash;
110 
111 	/* background prealloc block trimming */
112 	struct delayed_work	pag_blockgc_work;
113 
114 	/*
115 	 * We use xfs_drain to track the number of deferred log intent items
116 	 * that have been queued (but not yet processed) so that waiters (e.g.
117 	 * scrub) will not lock resources when other threads are in the middle
118 	 * of processing a chain of intent items only to find momentary
119 	 * inconsistencies.
120 	 */
121 	struct xfs_defer_drain	pag_intents_drain;
122 #endif /* __KERNEL__ */
123 };
124 
125 /*
126  * Per-AG operational state. These are atomic flag bits.
127  */
128 #define XFS_AGSTATE_AGF_INIT		0
129 #define XFS_AGSTATE_AGI_INIT		1
130 #define XFS_AGSTATE_PREFERS_METADATA	2
131 #define XFS_AGSTATE_ALLOWS_INODES	3
132 #define XFS_AGSTATE_AGFL_NEEDS_RESET	4
133 
134 #define __XFS_AG_OPSTATE(name, NAME) \
135 static inline bool xfs_perag_ ## name (struct xfs_perag *pag) \
136 { \
137 	return test_bit(XFS_AGSTATE_ ## NAME, &pag->pag_opstate); \
138 }
139 
140 __XFS_AG_OPSTATE(initialised_agf, AGF_INIT)
141 __XFS_AG_OPSTATE(initialised_agi, AGI_INIT)
142 __XFS_AG_OPSTATE(prefers_metadata, PREFERS_METADATA)
143 __XFS_AG_OPSTATE(allows_inodes, ALLOWS_INODES)
144 __XFS_AG_OPSTATE(agfl_needs_reset, AGFL_NEEDS_RESET)
145 
146 void xfs_free_unused_perag_range(struct xfs_mount *mp, xfs_agnumber_t agstart,
147 			xfs_agnumber_t agend);
148 int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
149 			xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
150 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
151 void xfs_free_perag(struct xfs_mount *mp);
152 
153 /* Passive AG references */
154 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
155 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
156 		unsigned int tag);
157 struct xfs_perag *xfs_perag_hold(struct xfs_perag *pag);
158 void xfs_perag_put(struct xfs_perag *pag);
159 
160 /* Active AG references */
161 struct xfs_perag *xfs_perag_grab(struct xfs_mount *, xfs_agnumber_t);
162 struct xfs_perag *xfs_perag_grab_tag(struct xfs_mount *, xfs_agnumber_t,
163 				   int tag);
164 void xfs_perag_rele(struct xfs_perag *pag);
165 
166 /*
167  * Per-ag geometry infomation and validation
168  */
169 xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
170 void xfs_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
171 		xfs_agino_t *first, xfs_agino_t *last);
172 
173 static inline bool
174 xfs_verify_agbno(struct xfs_perag *pag, xfs_agblock_t agbno)
175 {
176 	if (agbno >= pag->block_count)
177 		return false;
178 	if (agbno <= pag->min_block)
179 		return false;
180 	return true;
181 }
182 
183 static inline bool
184 xfs_verify_agbext(
185 	struct xfs_perag	*pag,
186 	xfs_agblock_t		agbno,
187 	xfs_agblock_t		len)
188 {
189 	if (agbno + len <= agbno)
190 		return false;
191 
192 	if (!xfs_verify_agbno(pag, agbno))
193 		return false;
194 
195 	return xfs_verify_agbno(pag, agbno + len - 1);
196 }
197 
198 /*
199  * Verify that an AG inode number pointer neither points outside the AG
200  * nor points at static metadata.
201  */
202 static inline bool
203 xfs_verify_agino(struct xfs_perag *pag, xfs_agino_t agino)
204 {
205 	if (agino < pag->agino_min)
206 		return false;
207 	if (agino > pag->agino_max)
208 		return false;
209 	return true;
210 }
211 
212 /*
213  * Verify that an AG inode number pointer neither points outside the AG
214  * nor points at static metadata, or is NULLAGINO.
215  */
216 static inline bool
217 xfs_verify_agino_or_null(struct xfs_perag *pag, xfs_agino_t agino)
218 {
219 	if (agino == NULLAGINO)
220 		return true;
221 	return xfs_verify_agino(pag, agino);
222 }
223 
224 static inline bool
225 xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
226 {
227 	return mp->m_sb.sb_logstart > 0 &&
228 	       agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
229 }
230 
231 /*
232  * Perag iteration APIs
233  */
234 static inline struct xfs_perag *
235 xfs_perag_next(
236 	struct xfs_perag	*pag,
237 	xfs_agnumber_t		*agno,
238 	xfs_agnumber_t		end_agno)
239 {
240 	struct xfs_mount	*mp = pag->pag_mount;
241 
242 	*agno = pag->pag_agno + 1;
243 	xfs_perag_rele(pag);
244 	while (*agno <= end_agno) {
245 		pag = xfs_perag_grab(mp, *agno);
246 		if (pag)
247 			return pag;
248 		(*agno)++;
249 	}
250 	return NULL;
251 }
252 
253 #define for_each_perag_range(mp, agno, end_agno, pag) \
254 	for ((pag) = xfs_perag_grab((mp), (agno)); \
255 		(pag) != NULL; \
256 		(pag) = xfs_perag_next((pag), &(agno), (end_agno)))
257 
258 #define for_each_perag_from(mp, agno, pag) \
259 	for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
260 
261 #define for_each_perag(mp, agno, pag) \
262 	(agno) = 0; \
263 	for_each_perag_from((mp), (agno), (pag))
264 
265 #define for_each_perag_tag(mp, agno, pag, tag) \
266 	for ((agno) = 0, (pag) = xfs_perag_grab_tag((mp), 0, (tag)); \
267 		(pag) != NULL; \
268 		(agno) = (pag)->pag_agno + 1, \
269 		xfs_perag_rele(pag), \
270 		(pag) = xfs_perag_grab_tag((mp), (agno), (tag)))
271 
272 static inline struct xfs_perag *
273 xfs_perag_next_wrap(
274 	struct xfs_perag	*pag,
275 	xfs_agnumber_t		*agno,
276 	xfs_agnumber_t		stop_agno,
277 	xfs_agnumber_t		restart_agno,
278 	xfs_agnumber_t		wrap_agno)
279 {
280 	struct xfs_mount	*mp = pag->pag_mount;
281 
282 	*agno = pag->pag_agno + 1;
283 	xfs_perag_rele(pag);
284 	while (*agno != stop_agno) {
285 		if (*agno >= wrap_agno) {
286 			if (restart_agno >= stop_agno)
287 				break;
288 			*agno = restart_agno;
289 		}
290 
291 		pag = xfs_perag_grab(mp, *agno);
292 		if (pag)
293 			return pag;
294 		(*agno)++;
295 	}
296 	return NULL;
297 }
298 
299 /*
300  * Iterate all AGs from start_agno through wrap_agno, then restart_agno through
301  * (start_agno - 1).
302  */
303 #define for_each_perag_wrap_range(mp, start_agno, restart_agno, wrap_agno, agno, pag) \
304 	for ((agno) = (start_agno), (pag) = xfs_perag_grab((mp), (agno)); \
305 		(pag) != NULL; \
306 		(pag) = xfs_perag_next_wrap((pag), &(agno), (start_agno), \
307 				(restart_agno), (wrap_agno)))
308 /*
309  * Iterate all AGs from start_agno through wrap_agno, then 0 through
310  * (start_agno - 1).
311  */
312 #define for_each_perag_wrap_at(mp, start_agno, wrap_agno, agno, pag) \
313 	for_each_perag_wrap_range((mp), (start_agno), 0, (wrap_agno), (agno), (pag))
314 
315 /*
316  * Iterate all AGs from start_agno through to the end of the filesystem, then 0
317  * through (start_agno - 1).
318  */
319 #define for_each_perag_wrap(mp, start_agno, agno, pag) \
320 	for_each_perag_wrap_at((mp), (start_agno), (mp)->m_sb.sb_agcount, \
321 				(agno), (pag))
322 
323 
324 struct aghdr_init_data {
325 	/* per ag data */
326 	xfs_agblock_t		agno;		/* ag to init */
327 	xfs_extlen_t		agsize;		/* new AG size */
328 	struct list_head	buffer_list;	/* buffer writeback list */
329 	xfs_rfsblock_t		nfree;		/* cumulative new free space */
330 
331 	/* per header data */
332 	xfs_daddr_t		daddr;		/* header location */
333 	size_t			numblks;	/* size of header */
334 	xfs_btnum_t		type;		/* type of btree root block */
335 };
336 
337 int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
338 int xfs_ag_shrink_space(struct xfs_perag *pag, struct xfs_trans **tpp,
339 			xfs_extlen_t delta);
340 int xfs_ag_extend_space(struct xfs_perag *pag, struct xfs_trans *tp,
341 			xfs_extlen_t len);
342 int xfs_ag_get_geometry(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
343 
344 #endif /* __LIBXFS_AG_H */
345