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
xfs_verify_agbno(struct xfs_perag * pag,xfs_agblock_t agbno)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
xfs_verify_agbext(struct xfs_perag * pag,xfs_agblock_t agbno,xfs_agblock_t len)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
xfs_verify_agino(struct xfs_perag * pag,xfs_agino_t agino)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
xfs_verify_agino_or_null(struct xfs_perag * pag,xfs_agino_t agino)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
xfs_ag_contains_log(struct xfs_mount * mp,xfs_agnumber_t agno)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 *
xfs_perag_next(struct xfs_perag * pag,xfs_agnumber_t * agno,xfs_agnumber_t end_agno)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 *
xfs_perag_next_wrap(struct xfs_perag * pag,xfs_agnumber_t * agno,xfs_agnumber_t stop_agno,xfs_agnumber_t restart_agno,xfs_agnumber_t wrap_agno)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