xref: /openbmc/linux/fs/xfs/libxfs/xfs_ag.h (revision 49c23519)
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 	spinlock_t	pag_state_lock;
84 
85 	spinlock_t	pagb_lock;	/* lock for pagb_tree */
86 	struct rb_root	pagb_tree;	/* ordered tree of busy extents */
87 	unsigned int	pagb_gen;	/* generation count for pagb_tree */
88 	wait_queue_head_t pagb_wait;	/* woken when pagb_gen changes */
89 
90 	atomic_t        pagf_fstrms;    /* # of filestreams active in this AG */
91 
92 	spinlock_t	pag_ici_lock;	/* incore inode cache lock */
93 	struct radix_tree_root pag_ici_root;	/* incore inode cache root */
94 	int		pag_ici_reclaimable;	/* reclaimable inodes */
95 	unsigned long	pag_ici_reclaim_cursor;	/* reclaim restart point */
96 
97 	/* buffer cache index */
98 	spinlock_t	pag_buf_lock;	/* lock for pag_buf_hash */
99 	struct rhashtable pag_buf_hash;
100 
101 	/* background prealloc block trimming */
102 	struct delayed_work	pag_blockgc_work;
103 
104 	/*
105 	 * We use xfs_drain to track the number of deferred log intent items
106 	 * that have been queued (but not yet processed) so that waiters (e.g.
107 	 * scrub) will not lock resources when other threads are in the middle
108 	 * of processing a chain of intent items only to find momentary
109 	 * inconsistencies.
110 	 */
111 	struct xfs_defer_drain	pag_intents_drain;
112 #endif /* __KERNEL__ */
113 };
114 
115 /*
116  * Per-AG operational state. These are atomic flag bits.
117  */
118 #define XFS_AGSTATE_AGF_INIT		0
119 #define XFS_AGSTATE_AGI_INIT		1
120 #define XFS_AGSTATE_PREFERS_METADATA	2
121 #define XFS_AGSTATE_ALLOWS_INODES	3
122 #define XFS_AGSTATE_AGFL_NEEDS_RESET	4
123 
124 #define __XFS_AG_OPSTATE(name, NAME) \
125 static inline bool xfs_perag_ ## name (struct xfs_perag *pag) \
126 { \
127 	return test_bit(XFS_AGSTATE_ ## NAME, &pag->pag_opstate); \
128 }
129 
130 __XFS_AG_OPSTATE(initialised_agf, AGF_INIT)
131 __XFS_AG_OPSTATE(initialised_agi, AGI_INIT)
132 __XFS_AG_OPSTATE(prefers_metadata, PREFERS_METADATA)
133 __XFS_AG_OPSTATE(allows_inodes, ALLOWS_INODES)
134 __XFS_AG_OPSTATE(agfl_needs_reset, AGFL_NEEDS_RESET)
135 
136 void xfs_free_unused_perag_range(struct xfs_mount *mp, xfs_agnumber_t agstart,
137 			xfs_agnumber_t agend);
138 int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
139 			xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
140 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
141 void xfs_free_perag(struct xfs_mount *mp);
142 
143 /* Passive AG references */
144 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
145 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
146 		unsigned int tag);
147 struct xfs_perag *xfs_perag_hold(struct xfs_perag *pag);
148 void xfs_perag_put(struct xfs_perag *pag);
149 
150 /* Active AG references */
151 struct xfs_perag *xfs_perag_grab(struct xfs_mount *, xfs_agnumber_t);
152 struct xfs_perag *xfs_perag_grab_tag(struct xfs_mount *, xfs_agnumber_t,
153 				   int tag);
154 void xfs_perag_rele(struct xfs_perag *pag);
155 
156 /*
157  * Per-ag geometry infomation and validation
158  */
159 xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
160 void xfs_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
161 		xfs_agino_t *first, xfs_agino_t *last);
162 
163 static inline bool
164 xfs_verify_agbno(struct xfs_perag *pag, xfs_agblock_t agbno)
165 {
166 	if (agbno >= pag->block_count)
167 		return false;
168 	if (agbno <= pag->min_block)
169 		return false;
170 	return true;
171 }
172 
173 static inline bool
174 xfs_verify_agbext(
175 	struct xfs_perag	*pag,
176 	xfs_agblock_t		agbno,
177 	xfs_agblock_t		len)
178 {
179 	if (agbno + len <= agbno)
180 		return false;
181 
182 	if (!xfs_verify_agbno(pag, agbno))
183 		return false;
184 
185 	return xfs_verify_agbno(pag, agbno + len - 1);
186 }
187 
188 /*
189  * Verify that an AG inode number pointer neither points outside the AG
190  * nor points at static metadata.
191  */
192 static inline bool
193 xfs_verify_agino(struct xfs_perag *pag, xfs_agino_t agino)
194 {
195 	if (agino < pag->agino_min)
196 		return false;
197 	if (agino > pag->agino_max)
198 		return false;
199 	return true;
200 }
201 
202 /*
203  * Verify that an AG inode number pointer neither points outside the AG
204  * nor points at static metadata, or is NULLAGINO.
205  */
206 static inline bool
207 xfs_verify_agino_or_null(struct xfs_perag *pag, xfs_agino_t agino)
208 {
209 	if (agino == NULLAGINO)
210 		return true;
211 	return xfs_verify_agino(pag, agino);
212 }
213 
214 static inline bool
215 xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
216 {
217 	return mp->m_sb.sb_logstart > 0 &&
218 	       agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
219 }
220 
221 /*
222  * Perag iteration APIs
223  */
224 static inline struct xfs_perag *
225 xfs_perag_next(
226 	struct xfs_perag	*pag,
227 	xfs_agnumber_t		*agno,
228 	xfs_agnumber_t		end_agno)
229 {
230 	struct xfs_mount	*mp = pag->pag_mount;
231 
232 	*agno = pag->pag_agno + 1;
233 	xfs_perag_rele(pag);
234 	while (*agno <= end_agno) {
235 		pag = xfs_perag_grab(mp, *agno);
236 		if (pag)
237 			return pag;
238 		(*agno)++;
239 	}
240 	return NULL;
241 }
242 
243 #define for_each_perag_range(mp, agno, end_agno, pag) \
244 	for ((pag) = xfs_perag_grab((mp), (agno)); \
245 		(pag) != NULL; \
246 		(pag) = xfs_perag_next((pag), &(agno), (end_agno)))
247 
248 #define for_each_perag_from(mp, agno, pag) \
249 	for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
250 
251 #define for_each_perag(mp, agno, pag) \
252 	(agno) = 0; \
253 	for_each_perag_from((mp), (agno), (pag))
254 
255 #define for_each_perag_tag(mp, agno, pag, tag) \
256 	for ((agno) = 0, (pag) = xfs_perag_grab_tag((mp), 0, (tag)); \
257 		(pag) != NULL; \
258 		(agno) = (pag)->pag_agno + 1, \
259 		xfs_perag_rele(pag), \
260 		(pag) = xfs_perag_grab_tag((mp), (agno), (tag)))
261 
262 static inline struct xfs_perag *
263 xfs_perag_next_wrap(
264 	struct xfs_perag	*pag,
265 	xfs_agnumber_t		*agno,
266 	xfs_agnumber_t		stop_agno,
267 	xfs_agnumber_t		restart_agno,
268 	xfs_agnumber_t		wrap_agno)
269 {
270 	struct xfs_mount	*mp = pag->pag_mount;
271 
272 	*agno = pag->pag_agno + 1;
273 	xfs_perag_rele(pag);
274 	while (*agno != stop_agno) {
275 		if (*agno >= wrap_agno) {
276 			if (restart_agno >= stop_agno)
277 				break;
278 			*agno = restart_agno;
279 		}
280 
281 		pag = xfs_perag_grab(mp, *agno);
282 		if (pag)
283 			return pag;
284 		(*agno)++;
285 	}
286 	return NULL;
287 }
288 
289 /*
290  * Iterate all AGs from start_agno through wrap_agno, then restart_agno through
291  * (start_agno - 1).
292  */
293 #define for_each_perag_wrap_range(mp, start_agno, restart_agno, wrap_agno, agno, pag) \
294 	for ((agno) = (start_agno), (pag) = xfs_perag_grab((mp), (agno)); \
295 		(pag) != NULL; \
296 		(pag) = xfs_perag_next_wrap((pag), &(agno), (start_agno), \
297 				(restart_agno), (wrap_agno)))
298 /*
299  * Iterate all AGs from start_agno through wrap_agno, then 0 through
300  * (start_agno - 1).
301  */
302 #define for_each_perag_wrap_at(mp, start_agno, wrap_agno, agno, pag) \
303 	for_each_perag_wrap_range((mp), (start_agno), 0, (wrap_agno), (agno), (pag))
304 
305 /*
306  * Iterate all AGs from start_agno through to the end of the filesystem, then 0
307  * through (start_agno - 1).
308  */
309 #define for_each_perag_wrap(mp, start_agno, agno, pag) \
310 	for_each_perag_wrap_at((mp), (start_agno), (mp)->m_sb.sb_agcount, \
311 				(agno), (pag))
312 
313 
314 struct aghdr_init_data {
315 	/* per ag data */
316 	xfs_agblock_t		agno;		/* ag to init */
317 	xfs_extlen_t		agsize;		/* new AG size */
318 	struct list_head	buffer_list;	/* buffer writeback list */
319 	xfs_rfsblock_t		nfree;		/* cumulative new free space */
320 
321 	/* per header data */
322 	xfs_daddr_t		daddr;		/* header location */
323 	size_t			numblks;	/* size of header */
324 	xfs_btnum_t		type;		/* type of btree root block */
325 };
326 
327 int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
328 int xfs_ag_shrink_space(struct xfs_perag *pag, struct xfs_trans **tpp,
329 			xfs_extlen_t delta);
330 int xfs_ag_extend_space(struct xfs_perag *pag, struct xfs_trans *tp,
331 			xfs_extlen_t len);
332 int xfs_ag_get_geometry(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
333 
334 #endif /* __LIBXFS_AG_H */
335