1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * suballoc.h
5 *
6 * Defines sub allocator api
7 *
8 * Copyright (C) 2003, 2004 Oracle. 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 as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 */
25
26 #ifndef _CHAINALLOC_H_
27 #define _CHAINALLOC_H_
28
29 typedef int (group_search_t)(struct inode *,
30 struct buffer_head *,
31 u32, /* bits_wanted */
32 u32, /* min_bits */
33 u64, /* max_block */
34 u16 *, /* *bit_off */
35 u16 *); /* *bits_found */
36
37 struct ocfs2_alloc_context {
38 struct inode *ac_inode; /* which bitmap are we allocating from? */
39 struct buffer_head *ac_bh; /* file entry bh */
40 u32 ac_alloc_slot; /* which slot are we allocating from? */
41 u32 ac_bits_wanted;
42 u32 ac_bits_given;
43 #define OCFS2_AC_USE_LOCAL 1
44 #define OCFS2_AC_USE_MAIN 2
45 #define OCFS2_AC_USE_INODE 3
46 #define OCFS2_AC_USE_META 4
47 u32 ac_which;
48
49 /* these are used by the chain search */
50 u16 ac_chain;
51 int ac_allow_chain_relink;
52 group_search_t *ac_group_search;
53
54 u64 ac_last_group;
55 u64 ac_max_block; /* Highest block number to allocate. 0 is
56 is the same as ~0 - unlimited */
57 };
58
59 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context * ac)60 static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
61 {
62 return ac->ac_bits_wanted - ac->ac_bits_given;
63 }
64
65 /*
66 * Please note that the caller must make sure that root_el is the root
67 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
68 * the result may be wrong.
69 */
70 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
71 struct ocfs2_extent_list *root_el,
72 struct ocfs2_alloc_context **ac);
73 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
74 int blocks,
75 struct ocfs2_alloc_context **ac);
76 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
77 struct ocfs2_alloc_context **ac);
78 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
79 u32 bits_wanted,
80 struct ocfs2_alloc_context **ac);
81
82 int ocfs2_claim_metadata(struct ocfs2_super *osb,
83 handle_t *handle,
84 struct ocfs2_alloc_context *ac,
85 u32 bits_wanted,
86 u16 *suballoc_bit_start,
87 u32 *num_bits,
88 u64 *blkno_start);
89 int ocfs2_claim_new_inode(struct ocfs2_super *osb,
90 handle_t *handle,
91 struct ocfs2_alloc_context *ac,
92 u16 *suballoc_bit,
93 u64 *fe_blkno);
94 int ocfs2_claim_clusters(struct ocfs2_super *osb,
95 handle_t *handle,
96 struct ocfs2_alloc_context *ac,
97 u32 min_clusters,
98 u32 *cluster_start,
99 u32 *num_clusters);
100 /*
101 * Use this variant of ocfs2_claim_clusters to specify a maxiumum
102 * number of clusters smaller than the allocation reserved.
103 */
104 int __ocfs2_claim_clusters(struct ocfs2_super *osb,
105 handle_t *handle,
106 struct ocfs2_alloc_context *ac,
107 u32 min_clusters,
108 u32 max_clusters,
109 u32 *cluster_start,
110 u32 *num_clusters);
111
112 int ocfs2_free_suballoc_bits(handle_t *handle,
113 struct inode *alloc_inode,
114 struct buffer_head *alloc_bh,
115 unsigned int start_bit,
116 u64 bg_blkno,
117 unsigned int count);
118 int ocfs2_free_dinode(handle_t *handle,
119 struct inode *inode_alloc_inode,
120 struct buffer_head *inode_alloc_bh,
121 struct ocfs2_dinode *di);
122 int ocfs2_free_clusters(handle_t *handle,
123 struct inode *bitmap_inode,
124 struct buffer_head *bitmap_bh,
125 u64 start_blk,
126 unsigned int num_clusters);
127
ocfs2_which_suballoc_group(u64 block,unsigned int bit)128 static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
129 {
130 u64 group = block - (u64) bit;
131
132 return group;
133 }
134
ocfs2_cluster_from_desc(struct ocfs2_super * osb,u64 bg_blkno)135 static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
136 u64 bg_blkno)
137 {
138 /* This should work for all block group descriptors as only
139 * the 1st group descriptor of the cluster bitmap is
140 * different. */
141
142 if (bg_blkno == osb->first_cluster_group_blkno)
143 return 0;
144
145 /* the rest of the block groups are located at the beginning
146 * of their 1st cluster, so a direct translation just
147 * works. */
148 return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
149 }
150
ocfs2_is_cluster_bitmap(struct inode * inode)151 static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
152 {
153 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
154 return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
155 }
156
157 /* This is for local alloc ONLY. Others should use the task-specific
158 * apis above. */
159 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
160 struct ocfs2_alloc_context *ac);
161 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
162
163 /* given a cluster offset, calculate which block group it belongs to
164 * and return that block offset. */
165 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
166
167 /*
168 * By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
169 * finds a problem. A caller that wants to check a group descriptor
170 * without going readonly should read the block with ocfs2_read_block[s]()
171 * and then checking it with this function. This is only resize, really.
172 * Everyone else should be using ocfs2_read_group_descriptor().
173 */
174 int ocfs2_check_group_descriptor(struct super_block *sb,
175 struct ocfs2_dinode *di,
176 struct buffer_head *bh);
177 /*
178 * Read a group descriptor block into *bh. If *bh is NULL, a bh will be
179 * allocated. This is a cached read. The descriptor will be validated with
180 * ocfs2_validate_group_descriptor().
181 */
182 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
183 u64 gd_blkno, struct buffer_head **bh);
184
185 int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
186 u32 clusters_to_add, u32 extents_to_split,
187 struct ocfs2_alloc_context **data_ac,
188 struct ocfs2_alloc_context **meta_ac);
189 #endif /* _CHAINALLOC_H_ */
190