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