xref: /linux/fs/xfs/libxfs/xfs_ag.h (revision 616500232e632dba8b03981eeccadacf2fbf1c30)
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 int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
137 			xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
138 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
139 void xfs_free_perag(struct xfs_mount *mp);
140 
141 /* Passive AG references */
142 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
143 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
144 		unsigned int tag);
145 struct xfs_perag *xfs_perag_hold(struct xfs_perag *pag);
146 void xfs_perag_put(struct xfs_perag *pag);
147 
148 /* Active AG references */
149 struct xfs_perag *xfs_perag_grab(struct xfs_mount *, xfs_agnumber_t);
150 struct xfs_perag *xfs_perag_grab_tag(struct xfs_mount *, xfs_agnumber_t,
151 				   int tag);
152 void xfs_perag_rele(struct xfs_perag *pag);
153 
154 /*
155  * Per-ag geometry infomation and validation
156  */
157 xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
158 void xfs_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
159 		xfs_agino_t *first, xfs_agino_t *last);
160 
161 static inline bool
162 xfs_verify_agbno(struct xfs_perag *pag, xfs_agblock_t agbno)
163 {
164 	if (agbno >= pag->block_count)
165 		return false;
166 	if (agbno <= pag->min_block)
167 		return false;
168 	return true;
169 }
170 
171 static inline bool
172 xfs_verify_agbext(
173 	struct xfs_perag	*pag,
174 	xfs_agblock_t		agbno,
175 	xfs_agblock_t		len)
176 {
177 	if (agbno + len <= agbno)
178 		return false;
179 
180 	if (!xfs_verify_agbno(pag, agbno))
181 		return false;
182 
183 	return xfs_verify_agbno(pag, agbno + len - 1);
184 }
185 
186 /*
187  * Verify that an AG inode number pointer neither points outside the AG
188  * nor points at static metadata.
189  */
190 static inline bool
191 xfs_verify_agino(struct xfs_perag *pag, xfs_agino_t agino)
192 {
193 	if (agino < pag->agino_min)
194 		return false;
195 	if (agino > pag->agino_max)
196 		return false;
197 	return true;
198 }
199 
200 /*
201  * Verify that an AG inode number pointer neither points outside the AG
202  * nor points at static metadata, or is NULLAGINO.
203  */
204 static inline bool
205 xfs_verify_agino_or_null(struct xfs_perag *pag, xfs_agino_t agino)
206 {
207 	if (agino == NULLAGINO)
208 		return true;
209 	return xfs_verify_agino(pag, agino);
210 }
211 
212 static inline bool
213 xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
214 {
215 	return mp->m_sb.sb_logstart > 0 &&
216 	       agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
217 }
218 
219 /*
220  * Perag iteration APIs
221  */
222 static inline struct xfs_perag *
223 xfs_perag_next(
224 	struct xfs_perag	*pag,
225 	xfs_agnumber_t		*agno,
226 	xfs_agnumber_t		end_agno)
227 {
228 	struct xfs_mount	*mp = pag->pag_mount;
229 
230 	*agno = pag->pag_agno + 1;
231 	xfs_perag_rele(pag);
232 	while (*agno <= end_agno) {
233 		pag = xfs_perag_grab(mp, *agno);
234 		if (pag)
235 			return pag;
236 		(*agno)++;
237 	}
238 	return NULL;
239 }
240 
241 #define for_each_perag_range(mp, agno, end_agno, pag) \
242 	for ((pag) = xfs_perag_grab((mp), (agno)); \
243 		(pag) != NULL; \
244 		(pag) = xfs_perag_next((pag), &(agno), (end_agno)))
245 
246 #define for_each_perag_from(mp, agno, pag) \
247 	for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
248 
249 #define for_each_perag(mp, agno, pag) \
250 	(agno) = 0; \
251 	for_each_perag_from((mp), (agno), (pag))
252 
253 #define for_each_perag_tag(mp, agno, pag, tag) \
254 	for ((agno) = 0, (pag) = xfs_perag_grab_tag((mp), 0, (tag)); \
255 		(pag) != NULL; \
256 		(agno) = (pag)->pag_agno + 1, \
257 		xfs_perag_rele(pag), \
258 		(pag) = xfs_perag_grab_tag((mp), (agno), (tag)))
259 
260 static inline struct xfs_perag *
261 xfs_perag_next_wrap(
262 	struct xfs_perag	*pag,
263 	xfs_agnumber_t		*agno,
264 	xfs_agnumber_t		stop_agno,
265 	xfs_agnumber_t		restart_agno,
266 	xfs_agnumber_t		wrap_agno)
267 {
268 	struct xfs_mount	*mp = pag->pag_mount;
269 
270 	*agno = pag->pag_agno + 1;
271 	xfs_perag_rele(pag);
272 	while (*agno != stop_agno) {
273 		if (*agno >= wrap_agno) {
274 			if (restart_agno >= stop_agno)
275 				break;
276 			*agno = restart_agno;
277 		}
278 
279 		pag = xfs_perag_grab(mp, *agno);
280 		if (pag)
281 			return pag;
282 		(*agno)++;
283 	}
284 	return NULL;
285 }
286 
287 /*
288  * Iterate all AGs from start_agno through wrap_agno, then restart_agno through
289  * (start_agno - 1).
290  */
291 #define for_each_perag_wrap_range(mp, start_agno, restart_agno, wrap_agno, agno, pag) \
292 	for ((agno) = (start_agno), (pag) = xfs_perag_grab((mp), (agno)); \
293 		(pag) != NULL; \
294 		(pag) = xfs_perag_next_wrap((pag), &(agno), (start_agno), \
295 				(restart_agno), (wrap_agno)))
296 /*
297  * Iterate all AGs from start_agno through wrap_agno, then 0 through
298  * (start_agno - 1).
299  */
300 #define for_each_perag_wrap_at(mp, start_agno, wrap_agno, agno, pag) \
301 	for_each_perag_wrap_range((mp), (start_agno), 0, (wrap_agno), (agno), (pag))
302 
303 /*
304  * Iterate all AGs from start_agno through to the end of the filesystem, then 0
305  * through (start_agno - 1).
306  */
307 #define for_each_perag_wrap(mp, start_agno, agno, pag) \
308 	for_each_perag_wrap_at((mp), (start_agno), (mp)->m_sb.sb_agcount, \
309 				(agno), (pag))
310 
311 
312 struct aghdr_init_data {
313 	/* per ag data */
314 	xfs_agblock_t		agno;		/* ag to init */
315 	xfs_extlen_t		agsize;		/* new AG size */
316 	struct list_head	buffer_list;	/* buffer writeback list */
317 	xfs_rfsblock_t		nfree;		/* cumulative new free space */
318 
319 	/* per header data */
320 	xfs_daddr_t		daddr;		/* header location */
321 	size_t			numblks;	/* size of header */
322 	xfs_btnum_t		type;		/* type of btree root block */
323 };
324 
325 int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
326 int xfs_ag_shrink_space(struct xfs_perag *pag, struct xfs_trans **tpp,
327 			xfs_extlen_t delta);
328 int xfs_ag_extend_space(struct xfs_perag *pag, struct xfs_trans *tp,
329 			xfs_extlen_t len);
330 int xfs_ag_get_geometry(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
331 
332 #endif /* __LIBXFS_AG_H */
333