1 /* SPDX-License-Identifier: GPL-2.0-only */ !! 1 /* -*- mode: c; c-basic-offset: 8; -*-
2 /* !! 2 * vim: noexpandtab sw=8 ts=8 sts=0:
>> 3 *
3 * reservations.h 4 * reservations.h
4 * 5 *
5 * Allocation reservations function prototypes 6 * Allocation reservations function prototypes and structures.
6 * 7 *
7 * Copyright (C) 2010 Novell. All rights rese 8 * Copyright (C) 2010 Novell. All rights reserved.
>> 9 *
>> 10 * This program is free software; you can redistribute it and/or
>> 11 * modify it under the terms of the GNU General Public
>> 12 * License version 2 as published by the Free Software Foundation.
>> 13 *
>> 14 * This program is distributed in the hope that it will be useful,
>> 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>> 17 * General Public License for more details.
8 */ 18 */
9 19
10 #ifndef OCFS2_RESERVATIONS_H 20 #ifndef OCFS2_RESERVATIONS_H
11 #define OCFS2_RESERVATIONS_H 21 #define OCFS2_RESERVATIONS_H
12 22
13 #include <linux/rbtree.h> 23 #include <linux/rbtree.h>
14 24
15 #define OCFS2_DEFAULT_RESV_LEVEL 2 25 #define OCFS2_DEFAULT_RESV_LEVEL 2
16 #define OCFS2_MAX_RESV_LEVEL 9 26 #define OCFS2_MAX_RESV_LEVEL 9
17 #define OCFS2_MIN_RESV_LEVEL 0 27 #define OCFS2_MIN_RESV_LEVEL 0
18 28
19 struct ocfs2_alloc_reservation { 29 struct ocfs2_alloc_reservation {
20 struct rb_node r_node; 30 struct rb_node r_node;
21 31
22 unsigned int r_start; /* Beg 32 unsigned int r_start; /* Beginning of current window */
23 unsigned int r_len; /* Len 33 unsigned int r_len; /* Length of the window */
24 34
25 unsigned int r_last_len; /* Len 35 unsigned int r_last_len; /* Length of most recent alloc */
26 unsigned int r_last_start; /* Sta 36 unsigned int r_last_start; /* Start of most recent alloc */
27 struct list_head r_lru; /* LRU 37 struct list_head r_lru; /* LRU list head */
28 38
29 unsigned int r_flags; 39 unsigned int r_flags;
30 }; 40 };
31 41
32 #define OCFS2_RESV_FLAG_INUSE 0x01 /* Set 42 #define OCFS2_RESV_FLAG_INUSE 0x01 /* Set when r_node is part of a btree */
33 #define OCFS2_RESV_FLAG_TMP 0x02 /* Tem 43 #define OCFS2_RESV_FLAG_TMP 0x02 /* Temporary reservation, will be
34 * des 44 * destroyed immedately after use */
35 #define OCFS2_RESV_FLAG_DIR 0x04 /* Res 45 #define OCFS2_RESV_FLAG_DIR 0x04 /* Reservation is for an unindexed
36 * dir 46 * directory btree */
37 47
38 struct ocfs2_reservation_map { 48 struct ocfs2_reservation_map {
39 struct rb_root m_reservations 49 struct rb_root m_reservations;
40 char *m_disk_bitmap 50 char *m_disk_bitmap;
41 51
42 struct ocfs2_super *m_osb; 52 struct ocfs2_super *m_osb;
43 53
44 /* The following are not initialized t 54 /* The following are not initialized to meaningful values until a disk
45 * bitmap is provided. */ 55 * bitmap is provided. */
46 u32 m_bitmap_len; 56 u32 m_bitmap_len; /* Number of valid
47 57 * bits available */
48 58
49 struct list_head m_lru; 59 struct list_head m_lru; /* LRU of reservations
50 60 * structures. */
51 61
52 }; 62 };
53 63
54 void ocfs2_resv_init_once(struct ocfs2_alloc_r 64 void ocfs2_resv_init_once(struct ocfs2_alloc_reservation *resv);
55 65
56 #define OCFS2_RESV_TYPES (OCFS2_RESV_FL 66 #define OCFS2_RESV_TYPES (OCFS2_RESV_FLAG_TMP|OCFS2_RESV_FLAG_DIR)
57 void ocfs2_resv_set_type(struct ocfs2_alloc_re 67 void ocfs2_resv_set_type(struct ocfs2_alloc_reservation *resv,
58 unsigned int flags); 68 unsigned int flags);
59 69
60 int ocfs2_dir_resv_allowed(struct ocfs2_super 70 int ocfs2_dir_resv_allowed(struct ocfs2_super *osb);
61 71
62 /** 72 /**
63 * ocfs2_resv_discard() - truncate a reservati 73 * ocfs2_resv_discard() - truncate a reservation
64 * @resmap: 74 * @resmap:
65 * @resv: the reservation to truncate. 75 * @resv: the reservation to truncate.
66 * 76 *
67 * After this function is called, the reservat 77 * After this function is called, the reservation will be empty, and
68 * unlinked from the rbtree. 78 * unlinked from the rbtree.
69 */ 79 */
70 void ocfs2_resv_discard(struct ocfs2_reservati 80 void ocfs2_resv_discard(struct ocfs2_reservation_map *resmap,
71 struct ocfs2_alloc_res 81 struct ocfs2_alloc_reservation *resv);
72 82
73 83
74 /** 84 /**
75 * ocfs2_resmap_init() - Initialize fields of 85 * 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 86 * @resmap: struct ocfs2_reservation_map to initialize
>> 87 * @obj: unused for now
>> 88 * @ops: unused for now
>> 89 * @max_bitmap_bytes: Maximum size of the bitmap (typically blocksize)
>> 90 *
>> 91 * Only possible return value other than '' is -ENOMEM for failure to
>> 92 * allocation mirror bitmap.
78 */ 93 */
79 void ocfs2_resmap_init(struct ocfs2_super *osb !! 94 int ocfs2_resmap_init(struct ocfs2_super *osb,
80 struct ocfs2_reservation 95 struct ocfs2_reservation_map *resmap);
81 96
82 /** 97 /**
83 * ocfs2_resmap_restart() - "restart" a reserv 98 * ocfs2_resmap_restart() - "restart" a reservation bitmap
84 * @resmap: reservations bitmap 99 * @resmap: reservations bitmap
85 * @clen: Number of valid bits in the bitmap 100 * @clen: Number of valid bits in the bitmap
86 * @disk_bitmap: the disk bitmap this resmap s 101 * @disk_bitmap: the disk bitmap this resmap should refer to.
87 * 102 *
88 * Re-initialize the parameters of a reservati 103 * Re-initialize the parameters of a reservation bitmap. This is
89 * useful for local alloc window slides. 104 * useful for local alloc window slides.
90 * 105 *
91 * This function will call ocfs2_trunc_resv ag 106 * This function will call ocfs2_trunc_resv against all existing
92 * reservations. A future version will recalcu 107 * reservations. A future version will recalculate existing
93 * reservations based on the new bitmap. 108 * reservations based on the new bitmap.
94 */ 109 */
95 void ocfs2_resmap_restart(struct ocfs2_reserva 110 void ocfs2_resmap_restart(struct ocfs2_reservation_map *resmap,
96 unsigned int clen, c 111 unsigned int clen, char *disk_bitmap);
97 112
98 /** 113 /**
99 * ocfs2_resmap_uninit() - uninitialize a rese 114 * ocfs2_resmap_uninit() - uninitialize a reservation bitmap structure
100 * @resmap: the struct ocfs2_reservation_map t 115 * @resmap: the struct ocfs2_reservation_map to uninitialize
101 */ 116 */
102 void ocfs2_resmap_uninit(struct ocfs2_reservat 117 void ocfs2_resmap_uninit(struct ocfs2_reservation_map *resmap);
103 118
104 /** 119 /**
105 * ocfs2_resmap_resv_bits() - Return still-val 120 * ocfs2_resmap_resv_bits() - Return still-valid reservation bits
106 * @resmap: reservations bitmap 121 * @resmap: reservations bitmap
107 * @resv: reservation to base search from 122 * @resv: reservation to base search from
108 * @cstart: start of proposed allocation 123 * @cstart: start of proposed allocation
109 * @clen: length (in clusters) of proposed all 124 * @clen: length (in clusters) of proposed allocation
110 * 125 *
111 * Using the reservation data from resv, this 126 * Using the reservation data from resv, this function will compare
112 * resmap and resmap->m_disk_bitmap to determi 127 * resmap and resmap->m_disk_bitmap to determine what part (if any) of
113 * the reservation window is still clear to us 128 * the reservation window is still clear to use. If resv is empty,
114 * this function will try to allocate a window 129 * this function will try to allocate a window for it.
115 * 130 *
116 * On success, zero is returned and the valid 131 * On success, zero is returned and the valid allocation area is set in cstart
117 * and clen. 132 * and clen.
118 * 133 *
119 * Returns -ENOSPC if reservations are disable 134 * Returns -ENOSPC if reservations are disabled.
120 */ 135 */
121 int ocfs2_resmap_resv_bits(struct ocfs2_reserv 136 int ocfs2_resmap_resv_bits(struct ocfs2_reservation_map *resmap,
122 struct ocfs2_alloc_ 137 struct ocfs2_alloc_reservation *resv,
123 int *cstart, int *c 138 int *cstart, int *clen);
124 139
125 /** 140 /**
126 * ocfs2_resmap_claimed_bits() - Tell the rese 141 * ocfs2_resmap_claimed_bits() - Tell the reservation code that bits were used.
127 * @resmap: reservations bitmap 142 * @resmap: reservations bitmap
128 * @resv: optional reservation to recalulate b 143 * @resv: optional reservation to recalulate based on new bitmap
129 * @cstart: start of allocation in clusters 144 * @cstart: start of allocation in clusters
130 * @clen: end of allocation in clusters. 145 * @clen: end of allocation in clusters.
131 * 146 *
132 * Tell the reservation code that bits were us 147 * Tell the reservation code that bits were used to fulfill allocation in
133 * resmap. The bits don't have to have been pa 148 * resmap. The bits don't have to have been part of any existing
134 * reservation. But we must always call this f 149 * reservation. But we must always call this function when bits are claimed.
135 * Internally, the reservations code will use 150 * Internally, the reservations code will use this information to mark the
136 * reservations bitmap. If resv is passed, it' 151 * reservations bitmap. If resv is passed, it's next allocation window will be
137 * calculated. It also expects that 'cstart' i 152 * calculated. It also expects that 'cstart' is the same as we passed back
138 * from ocfs2_resmap_resv_bits(). 153 * from ocfs2_resmap_resv_bits().
139 */ 154 */
140 void ocfs2_resmap_claimed_bits(struct ocfs2_re 155 void ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map *resmap,
141 struct ocfs2_al 156 struct ocfs2_alloc_reservation *resv,
142 u32 cstart, u32 157 u32 cstart, u32 clen);
143 158
144 #endif /* OCFS2_RESERVATIONS_H */ 159 #endif /* OCFS2_RESERVATIONS_H */
145 160
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