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; /* perag reference count */
36 char pagf_init; /* this agf's entry is initialized */
37 char pagi_init; /* this agi's entry is initialized */
38 char pagf_metadata; /* the agf is preferred to be metadata */
39 char pagi_inodeok; /* The agi is ok for inodes */
40 uint8_t pagf_levels[XFS_BTNUM_AGF];
41 /* # of levels in bno & cnt btree */
42 bool pagf_agflreset; /* agfl requires reset before use */
43 uint32_t pagf_flcount; /* count of blocks in freelist */
44 xfs_extlen_t pagf_freeblks; /* total free blocks */
45 xfs_extlen_t pagf_longest; /* longest free space */
46 uint32_t pagf_btreeblks; /* # of blocks held in AGF btrees */
47 xfs_agino_t pagi_freecount; /* number of free inodes */
48 xfs_agino_t pagi_count; /* number of allocated inodes */
49
50 /*
51 * Inode allocation search lookup optimisation.
52 * If the pagino matches, the search for new inodes
53 * doesn't need to search the near ones again straight away
54 */
55 xfs_agino_t pagl_pagino;
56 xfs_agino_t pagl_leftrec;
57 xfs_agino_t pagl_rightrec;
58
59 int pagb_count; /* pagb slots in use */
60 uint8_t pagf_refcount_level; /* recount btree height */
61
62 /* Blocks reserved for all kinds of metadata. */
63 struct xfs_ag_resv pag_meta_resv;
64 /* Blocks reserved for the reverse mapping btree. */
65 struct xfs_ag_resv pag_rmapbt_resv;
66
67 /* -- kernel only structures below this line -- */
68
69 /*
70 * Bitsets of per-ag metadata that have been checked and/or are sick.
71 * Callers should hold pag_state_lock before accessing this field.
72 */
73 uint16_t pag_checked;
74 uint16_t pag_sick;
75 spinlock_t pag_state_lock;
76
77 spinlock_t pagb_lock; /* lock for pagb_tree */
78 struct rb_root pagb_tree; /* ordered tree of busy extents */
79 unsigned int pagb_gen; /* generation count for pagb_tree */
80 wait_queue_head_t pagb_wait; /* woken when pagb_gen changes */
81
82 atomic_t pagf_fstrms; /* # of filestreams active in this AG */
83
84 spinlock_t pag_ici_lock; /* incore inode cache lock */
85 struct radix_tree_root pag_ici_root; /* incore inode cache root */
86 int pag_ici_reclaimable; /* reclaimable inodes */
87 unsigned long pag_ici_reclaim_cursor; /* reclaim restart point */
88
89 /* buffer cache index */
90 spinlock_t pag_buf_lock; /* lock for pag_buf_hash */
91 struct rhashtable pag_buf_hash;
92
93 /* for rcu-safe freeing */
94 struct rcu_head rcu_head;
95
96 /* background prealloc block trimming */
97 struct delayed_work pag_blockgc_work;
98
99 /*
100 * Unlinked inode information. This incore information reflects
101 * data stored in the AGI, so callers must hold the AGI buffer lock
102 * or have some other means to control concurrency.
103 */
104 struct rhashtable pagi_unlinked_hash;
105 };
106
107 int xfs_initialize_perag(struct xfs_mount *mp, xfs_agnumber_t agcount,
108 xfs_agnumber_t *maxagi);
109 int xfs_initialize_perag_data(struct xfs_mount *mp, xfs_agnumber_t agno);
110 void xfs_free_perag(struct xfs_mount *mp);
111
112 struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
113 struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
114 unsigned int tag);
115 void xfs_perag_put(struct xfs_perag *pag);
116
117 /*
118 * Perag iteration APIs
119 */
120 static inline struct xfs_perag *
xfs_perag_next(struct xfs_perag * pag,xfs_agnumber_t * agno,xfs_agnumber_t end_agno)121 xfs_perag_next(
122 struct xfs_perag *pag,
123 xfs_agnumber_t *agno,
124 xfs_agnumber_t end_agno)
125 {
126 struct xfs_mount *mp = pag->pag_mount;
127
128 *agno = pag->pag_agno + 1;
129 xfs_perag_put(pag);
130 if (*agno > end_agno)
131 return NULL;
132 return xfs_perag_get(mp, *agno);
133 }
134
135 #define for_each_perag_range(mp, agno, end_agno, pag) \
136 for ((pag) = xfs_perag_get((mp), (agno)); \
137 (pag) != NULL; \
138 (pag) = xfs_perag_next((pag), &(agno), (end_agno)))
139
140 #define for_each_perag_from(mp, agno, pag) \
141 for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
142
143
144 #define for_each_perag(mp, agno, pag) \
145 (agno) = 0; \
146 for_each_perag_from((mp), (agno), (pag))
147
148 #define for_each_perag_tag(mp, agno, pag, tag) \
149 for ((agno) = 0, (pag) = xfs_perag_get_tag((mp), 0, (tag)); \
150 (pag) != NULL; \
151 (agno) = (pag)->pag_agno + 1, \
152 xfs_perag_put(pag), \
153 (pag) = xfs_perag_get_tag((mp), (agno), (tag)))
154
155 struct aghdr_init_data {
156 /* per ag data */
157 xfs_agblock_t agno; /* ag to init */
158 xfs_extlen_t agsize; /* new AG size */
159 struct list_head buffer_list; /* buffer writeback list */
160 xfs_rfsblock_t nfree; /* cumulative new free space */
161
162 /* per header data */
163 xfs_daddr_t daddr; /* header location */
164 size_t numblks; /* size of header */
165 xfs_btnum_t type; /* type of btree root block */
166 };
167
168 int xfs_ag_init_headers(struct xfs_mount *mp, struct aghdr_init_data *id);
169 int xfs_ag_shrink_space(struct xfs_mount *mp, struct xfs_trans **tpp,
170 xfs_agnumber_t agno, xfs_extlen_t delta);
171 int xfs_ag_extend_space(struct xfs_mount *mp, struct xfs_trans *tp,
172 struct aghdr_init_data *id, xfs_extlen_t len);
173 int xfs_ag_get_geometry(struct xfs_mount *mp, xfs_agnumber_t agno,
174 struct xfs_ag_geometry *ageo);
175
176 #endif /* __LIBXFS_AG_H */
177