1 /* SPDX-License-Identifier: GPL-2.0-only */ 1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* !! 2 /* -*- mode: c; c-basic-offset: 8; -*-
>> 3 * vim: noexpandtab sw=8 ts=8 sts=0:
>> 4 *
3 * reservations.h 5 * reservations.h
4 * 6 *
5 * Allocation reservations function prototypes 7 * Allocation reservations function prototypes and structures.
6 * 8 *
7 * Copyright (C) 2010 Novell. All rights rese 9 * Copyright (C) 2010 Novell. All rights reserved.
8 */ 10 */
9 11
10 #ifndef OCFS2_RESERVATIONS_H 12 #ifndef OCFS2_RESERVATIONS_H
11 #define OCFS2_RESERVATIONS_H 13 #define OCFS2_RESERVATIONS_H
12 14
13 #include <linux/rbtree.h> 15 #include <linux/rbtree.h>
14 16
15 #define OCFS2_DEFAULT_RESV_LEVEL 2 17 #define OCFS2_DEFAULT_RESV_LEVEL 2
16 #define OCFS2_MAX_RESV_LEVEL 9 18 #define OCFS2_MAX_RESV_LEVEL 9
17 #define OCFS2_MIN_RESV_LEVEL 0 19 #define OCFS2_MIN_RESV_LEVEL 0
18 20
19 struct ocfs2_alloc_reservation { 21 struct ocfs2_alloc_reservation {
20 struct rb_node r_node; 22 struct rb_node r_node;
21 23
22 unsigned int r_start; /* Beg 24 unsigned int r_start; /* Beginning of current window */
23 unsigned int r_len; /* Len 25 unsigned int r_len; /* Length of the window */
24 26
25 unsigned int r_last_len; /* Len 27 unsigned int r_last_len; /* Length of most recent alloc */
26 unsigned int r_last_start; /* Sta 28 unsigned int r_last_start; /* Start of most recent alloc */
27 struct list_head r_lru; /* LRU 29 struct list_head r_lru; /* LRU list head */
28 30
29 unsigned int r_flags; 31 unsigned int r_flags;
30 }; 32 };
31 33
32 #define OCFS2_RESV_FLAG_INUSE 0x01 /* Set 34 #define OCFS2_RESV_FLAG_INUSE 0x01 /* Set when r_node is part of a btree */
33 #define OCFS2_RESV_FLAG_TMP 0x02 /* Tem 35 #define OCFS2_RESV_FLAG_TMP 0x02 /* Temporary reservation, will be
34 * des 36 * destroyed immedately after use */
35 #define OCFS2_RESV_FLAG_DIR 0x04 /* Res 37 #define OCFS2_RESV_FLAG_DIR 0x04 /* Reservation is for an unindexed
36 * dir 38 * directory btree */
37 39
38 struct ocfs2_reservation_map { 40 struct ocfs2_reservation_map {
39 struct rb_root m_reservations 41 struct rb_root m_reservations;
40 char *m_disk_bitmap 42 char *m_disk_bitmap;
41 43
42 struct ocfs2_super *m_osb; 44 struct ocfs2_super *m_osb;
43 45
44 /* The following are not initialized t 46 /* The following are not initialized to meaningful values until a disk
45 * bitmap is provided. */ 47 * bitmap is provided. */
46 u32 m_bitmap_len; 48 u32 m_bitmap_len; /* Number of valid
47 49 * bits available */
48 50
49 struct list_head m_lru; 51 struct list_head m_lru; /* LRU of reservations
50 52 * structures. */
51 53
52 }; 54 };
53 55
54 void ocfs2_resv_init_once(struct ocfs2_alloc_r 56 void ocfs2_resv_init_once(struct ocfs2_alloc_reservation *resv);
55 57
56 #define OCFS2_RESV_TYPES (OCFS2_RESV_FL 58 #define OCFS2_RESV_TYPES (OCFS2_RESV_FLAG_TMP|OCFS2_RESV_FLAG_DIR)
57 void ocfs2_resv_set_type(struct ocfs2_alloc_re 59 void ocfs2_resv_set_type(struct ocfs2_alloc_reservation *resv,
58 unsigned int flags); 60 unsigned int flags);
59 61
60 int ocfs2_dir_resv_allowed(struct ocfs2_super 62 int ocfs2_dir_resv_allowed(struct ocfs2_super *osb);
61 63
62 /** 64 /**
63 * ocfs2_resv_discard() - truncate a reservati 65 * ocfs2_resv_discard() - truncate a reservation
64 * @resmap: 66 * @resmap:
65 * @resv: the reservation to truncate. 67 * @resv: the reservation to truncate.
66 * 68 *
67 * After this function is called, the reservat 69 * After this function is called, the reservation will be empty, and
68 * unlinked from the rbtree. 70 * unlinked from the rbtree.
69 */ 71 */
70 void ocfs2_resv_discard(struct ocfs2_reservati 72 void ocfs2_resv_discard(struct ocfs2_reservation_map *resmap,
71 struct ocfs2_alloc_res 73 struct ocfs2_alloc_reservation *resv);
72 74
73 75
74 /** 76 /**
75 * ocfs2_resmap_init() - Initialize fields of 77 * ocfs2_resmap_init() - Initialize fields of a reservations bitmap
76 * @osb: struct ocfs2_super to be saved in res <<
77 * @resmap: struct ocfs2_reservation_map to in 78 * @resmap: struct ocfs2_reservation_map to initialize
>> 79 * @obj: unused for now
>> 80 * @ops: unused for now
>> 81 * @max_bitmap_bytes: Maximum size of the bitmap (typically blocksize)
>> 82 *
>> 83 * Only possible return value other than '' is -ENOMEM for failure to
>> 84 * allocation mirror bitmap.
78 */ 85 */
79 void ocfs2_resmap_init(struct ocfs2_super *osb !! 86 int ocfs2_resmap_init(struct ocfs2_super *osb,
80 struct ocfs2_reservation 87 struct ocfs2_reservation_map *resmap);
81 88
82 /** 89 /**
83 * ocfs2_resmap_restart() - "restart" a reserv 90 * ocfs2_resmap_restart() - "restart" a reservation bitmap
84 * @resmap: reservations bitmap 91 * @resmap: reservations bitmap
85 * @clen: Number of valid bits in the bitmap 92 * @clen: Number of valid bits in the bitmap
86 * @disk_bitmap: the disk bitmap this resmap s 93 * @disk_bitmap: the disk bitmap this resmap should refer to.
87 * 94 *
88 * Re-initialize the parameters of a reservati 95 * Re-initialize the parameters of a reservation bitmap. This is
89 * useful for local alloc window slides. 96 * useful for local alloc window slides.
90 * 97 *
91 * This function will call ocfs2_trunc_resv ag 98 * This function will call ocfs2_trunc_resv against all existing
92 * reservations. A future version will recalcu 99 * reservations. A future version will recalculate existing
93 * reservations based on the new bitmap. 100 * reservations based on the new bitmap.
94 */ 101 */
95 void ocfs2_resmap_restart(struct ocfs2_reserva 102 void ocfs2_resmap_restart(struct ocfs2_reservation_map *resmap,
96 unsigned int clen, c 103 unsigned int clen, char *disk_bitmap);
97 104
98 /** 105 /**
99 * ocfs2_resmap_uninit() - uninitialize a rese 106 * ocfs2_resmap_uninit() - uninitialize a reservation bitmap structure
100 * @resmap: the struct ocfs2_reservation_map t 107 * @resmap: the struct ocfs2_reservation_map to uninitialize
101 */ 108 */
102 void ocfs2_resmap_uninit(struct ocfs2_reservat 109 void ocfs2_resmap_uninit(struct ocfs2_reservation_map *resmap);
103 110
104 /** 111 /**
105 * ocfs2_resmap_resv_bits() - Return still-val 112 * ocfs2_resmap_resv_bits() - Return still-valid reservation bits
106 * @resmap: reservations bitmap 113 * @resmap: reservations bitmap
107 * @resv: reservation to base search from 114 * @resv: reservation to base search from
108 * @cstart: start of proposed allocation 115 * @cstart: start of proposed allocation
109 * @clen: length (in clusters) of proposed all 116 * @clen: length (in clusters) of proposed allocation
110 * 117 *
111 * Using the reservation data from resv, this 118 * Using the reservation data from resv, this function will compare
112 * resmap and resmap->m_disk_bitmap to determi 119 * resmap and resmap->m_disk_bitmap to determine what part (if any) of
113 * the reservation window is still clear to us 120 * the reservation window is still clear to use. If resv is empty,
114 * this function will try to allocate a window 121 * this function will try to allocate a window for it.
115 * 122 *
116 * On success, zero is returned and the valid 123 * On success, zero is returned and the valid allocation area is set in cstart
117 * and clen. 124 * and clen.
118 * 125 *
119 * Returns -ENOSPC if reservations are disable 126 * Returns -ENOSPC if reservations are disabled.
120 */ 127 */
121 int ocfs2_resmap_resv_bits(struct ocfs2_reserv 128 int ocfs2_resmap_resv_bits(struct ocfs2_reservation_map *resmap,
122 struct ocfs2_alloc_ 129 struct ocfs2_alloc_reservation *resv,
123 int *cstart, int *c 130 int *cstart, int *clen);
124 131
125 /** 132 /**
126 * ocfs2_resmap_claimed_bits() - Tell the rese 133 * ocfs2_resmap_claimed_bits() - Tell the reservation code that bits were used.
127 * @resmap: reservations bitmap 134 * @resmap: reservations bitmap
128 * @resv: optional reservation to recalulate b 135 * @resv: optional reservation to recalulate based on new bitmap
129 * @cstart: start of allocation in clusters 136 * @cstart: start of allocation in clusters
130 * @clen: end of allocation in clusters. 137 * @clen: end of allocation in clusters.
131 * 138 *
132 * Tell the reservation code that bits were us 139 * Tell the reservation code that bits were used to fulfill allocation in
133 * resmap. The bits don't have to have been pa 140 * resmap. The bits don't have to have been part of any existing
134 * reservation. But we must always call this f 141 * reservation. But we must always call this function when bits are claimed.
135 * Internally, the reservations code will use 142 * Internally, the reservations code will use this information to mark the
136 * reservations bitmap. If resv is passed, it' 143 * reservations bitmap. If resv is passed, it's next allocation window will be
137 * calculated. It also expects that 'cstart' i 144 * calculated. It also expects that 'cstart' is the same as we passed back
138 * from ocfs2_resmap_resv_bits(). 145 * from ocfs2_resmap_resv_bits().
139 */ 146 */
140 void ocfs2_resmap_claimed_bits(struct ocfs2_re 147 void ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map *resmap,
141 struct ocfs2_al 148 struct ocfs2_alloc_reservation *resv,
142 u32 cstart, u32 149 u32 cstart, u32 clen);
143 150
144 #endif /* OCFS2_RESERVATIONS_H */ 151 #endif /* OCFS2_RESERVATIONS_H */
145 152
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