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