xref: /linux/fs/xfs/libxfs/xfs_ag.h (revision 7a3a401874bea02f568aa416ac29170d8cde0dc2)
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 #endif /* __KERNEL__ */
105 };
106 
107 /*
108  * Per-AG operational state. These are atomic flag bits.
109  */
110 #define XFS_AGSTATE_AGF_INIT		0
111 #define XFS_AGSTATE_AGI_INIT		1
112 #define XFS_AGSTATE_PREFERS_METADATA	2
113 #define XFS_AGSTATE_ALLOWS_INODES	3
114 #define XFS_AGSTATE_AGFL_NEEDS_RESET	4
115 
116 #define __XFS_AG_OPSTATE(name, NAME) \
117 static inline bool xfs_perag_ ## name (struct xfs_perag *pag) \
118 { \
119 	return test_bit(XFS_AGSTATE_ ## NAME, &pag->pag_opstate); \
120 }
121 
122 __XFS_AG_OPSTATE(initialised_agf, AGF_INIT)
123 __XFS_AG_OPSTATE(initialised_agi, AGI_INIT)
124 __XFS_AG_OPSTATE(prefers_metadata, PREFERS_METADATA)
125 __XFS_AG_OPSTATE(allows_inodes, ALLOWS_INODES)
126 __XFS_AG_OPSTATE(agfl_needs_reset, AGFL_NEEDS_RESET)
127 
128 int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
129 			xfs_rfsblock_t dcount, xfs_agnumber_t *maxagi);
130 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
131 void xfs_free_perag(struct xfs_mount *mp);
132 
133 /* Passive AG references */
134 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
135 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
136 		unsigned int tag);
137 void xfs_perag_put(struct xfs_perag *pag);
138 
139 /* Active AG references */
140 struct xfs_perag *xfs_perag_grab(struct xfs_mount *, xfs_agnumber_t);
141 struct xfs_perag *xfs_perag_grab_tag(struct xfs_mount *, xfs_agnumber_t,
142 				   int tag);
143 void xfs_perag_rele(struct xfs_perag *pag);
144 
145 /*
146  * Per-ag geometry infomation and validation
147  */
148 xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
149 void xfs_agino_range(struct xfs_mount *mp, xfs_agnumber_t agno,
150 		xfs_agino_t *first, xfs_agino_t *last);
151 
152 static inline bool
153 xfs_verify_agbno(struct xfs_perag *pag, xfs_agblock_t agbno)
154 {
155 	if (agbno >= pag->block_count)
156 		return false;
157 	if (agbno <= pag->min_block)
158 		return false;
159 	return true;
160 }
161 
162 static inline bool
163 xfs_verify_agbext(
164 	struct xfs_perag	*pag,
165 	xfs_agblock_t		agbno,
166 	xfs_agblock_t		len)
167 {
168 	if (agbno + len <= agbno)
169 		return false;
170 
171 	if (!xfs_verify_agbno(pag, agbno))
172 		return false;
173 
174 	return xfs_verify_agbno(pag, agbno + len - 1);
175 }
176 
177 /*
178  * Verify that an AG inode number pointer neither points outside the AG
179  * nor points at static metadata.
180  */
181 static inline bool
182 xfs_verify_agino(struct xfs_perag *pag, xfs_agino_t agino)
183 {
184 	if (agino < pag->agino_min)
185 		return false;
186 	if (agino > pag->agino_max)
187 		return false;
188 	return true;
189 }
190 
191 /*
192  * Verify that an AG inode number pointer neither points outside the AG
193  * nor points at static metadata, or is NULLAGINO.
194  */
195 static inline bool
196 xfs_verify_agino_or_null(struct xfs_perag *pag, xfs_agino_t agino)
197 {
198 	if (agino == NULLAGINO)
199 		return true;
200 	return xfs_verify_agino(pag, agino);
201 }
202 
203 static inline bool
204 xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
205 {
206 	return mp->m_sb.sb_logstart > 0 &&
207 	       agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
208 }
209 
210 /*
211  * Perag iteration APIs
212  */
213 static inline struct xfs_perag *
214 xfs_perag_next(
215 	struct xfs_perag	*pag,
216 	xfs_agnumber_t		*agno,
217 	xfs_agnumber_t		end_agno)
218 {
219 	struct xfs_mount	*mp = pag->pag_mount;
220 
221 	*agno = pag->pag_agno + 1;
222 	xfs_perag_rele(pag);
223 	while (*agno <= end_agno) {
224 		pag = xfs_perag_grab(mp, *agno);
225 		if (pag)
226 			return pag;
227 		(*agno)++;
228 	}
229 	return NULL;
230 }
231 
232 #define for_each_perag_range(mp, agno, end_agno, pag) \
233 	for ((pag) = xfs_perag_grab((mp), (agno)); \
234 		(pag) != NULL; \
235 		(pag) = xfs_perag_next((pag), &(agno), (end_agno)))
236 
237 #define for_each_perag_from(mp, agno, pag) \
238 	for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
239 
240 #define for_each_perag(mp, agno, pag) \
241 	(agno) = 0; \
242 	for_each_perag_from((mp), (agno), (pag))
243 
244 #define for_each_perag_tag(mp, agno, pag, tag) \
245 	for ((agno) = 0, (pag) = xfs_perag_grab_tag((mp), 0, (tag)); \
246 		(pag) != NULL; \
247 		(agno) = (pag)->pag_agno + 1, \
248 		xfs_perag_rele(pag), \
249 		(pag) = xfs_perag_grab_tag((mp), (agno), (tag)))
250 
251 static inline struct xfs_perag *
252 xfs_perag_next_wrap(
253 	struct xfs_perag	*pag,
254 	xfs_agnumber_t		*agno,
255 	xfs_agnumber_t		stop_agno,
256 	xfs_agnumber_t		restart_agno,
257 	xfs_agnumber_t		wrap_agno)
258 {
259 	struct xfs_mount	*mp = pag->pag_mount;
260 
261 	*agno = pag->pag_agno + 1;
262 	xfs_perag_rele(pag);
263 	while (*agno != stop_agno) {
264 		if (*agno >= wrap_agno) {
265 			if (restart_agno >= stop_agno)
266 				break;
267 			*agno = restart_agno;
268 		}
269 
270 		pag = xfs_perag_grab(mp, *agno);
271 		if (pag)
272 			return pag;
273 		(*agno)++;
274 	}
275 	return NULL;
276 }
277 
278 /*
279  * Iterate all AGs from start_agno through wrap_agno, then restart_agno through
280  * (start_agno - 1).
281  */
282 #define for_each_perag_wrap_range(mp, start_agno, restart_agno, wrap_agno, agno, pag) \
283 	for ((agno) = (start_agno), (pag) = xfs_perag_grab((mp), (agno)); \
284 		(pag) != NULL; \
285 		(pag) = xfs_perag_next_wrap((pag), &(agno), (start_agno), \
286 				(restart_agno), (wrap_agno)))
287 /*
288  * Iterate all AGs from start_agno through wrap_agno, then 0 through
289  * (start_agno - 1).
290  */
291 #define for_each_perag_wrap_at(mp, start_agno, wrap_agno, agno, pag) \
292 	for_each_perag_wrap_range((mp), (start_agno), 0, (wrap_agno), (agno), (pag))
293 
294 /*
295  * Iterate all AGs from start_agno through to the end of the filesystem, then 0
296  * through (start_agno - 1).
297  */
298 #define for_each_perag_wrap(mp, start_agno, agno, pag) \
299 	for_each_perag_wrap_at((mp), (start_agno), (mp)->m_sb.sb_agcount, \
300 				(agno), (pag))
301 
302 
303 struct aghdr_init_data {
304 	/* per ag data */
305 	xfs_agblock_t		agno;		/* ag to init */
306 	xfs_extlen_t		agsize;		/* new AG size */
307 	struct list_head	buffer_list;	/* buffer writeback list */
308 	xfs_rfsblock_t		nfree;		/* cumulative new free space */
309 
310 	/* per header data */
311 	xfs_daddr_t		daddr;		/* header location */
312 	size_t			numblks;	/* size of header */
313 	xfs_btnum_t		type;		/* type of btree root block */
314 };
315 
316 int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
317 int xfs_ag_shrink_space(struct xfs_perag *pag, struct xfs_trans **tpp,
318 			xfs_extlen_t delta);
319 int xfs_ag_extend_space(struct xfs_perag *pag, struct xfs_trans *tp,
320 			xfs_extlen_t len);
321 int xfs_ag_get_geometry(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
322 
323 #endif /* __LIBXFS_AG_H */
324