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suballoc.h
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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 struct ocfs2_suballoc_result;
30 typedef int (group_search_t)(struct inode *,
31  struct buffer_head *,
32  u32, /* bits_wanted */
33  u32, /* min_bits */
34  u64, /* max_block */
35  struct ocfs2_suballoc_result *);
36  /* found bits */
37 
38 struct ocfs2_alloc_context {
39  struct inode *ac_inode; /* which bitmap are we allocating from? */
40  struct buffer_head *ac_bh; /* file entry bh */
41  u32 ac_alloc_slot; /* which slot are we allocating from? */
42  u32 ac_bits_wanted;
43  u32 ac_bits_given;
44 #define OCFS2_AC_USE_LOCAL 1
45 #define OCFS2_AC_USE_MAIN 2
46 #define OCFS2_AC_USE_INODE 3
47 #define OCFS2_AC_USE_META 4
48  u32 ac_which;
49 
50  /* these are used by the chain search */
51  u16 ac_chain;
52  int ac_allow_chain_relink;
53  group_search_t *ac_group_search;
54 
55  u64 ac_last_group;
56  u64 ac_max_block; /* Highest block number to allocate. 0 is
57  is the same as ~0 - unlimited */
58 
59  int ac_find_loc_only; /* hack for reflink operation ordering */
60  struct ocfs2_suballoc_result *ac_find_loc_priv; /* */
61 
62  struct ocfs2_alloc_reservation *ac_resv;
63 };
64 
65 void ocfs2_init_steal_slots(struct ocfs2_super *osb);
66 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
67 static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
68 {
69  return ac->ac_bits_wanted - ac->ac_bits_given;
70 }
71 
72 /*
73  * Please note that the caller must make sure that root_el is the root
74  * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
75  * the result may be wrong.
76  */
77 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
78  struct ocfs2_extent_list *root_el,
79  struct ocfs2_alloc_context **ac);
80 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
81  int blocks,
82  struct ocfs2_alloc_context **ac);
83 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
84  struct ocfs2_alloc_context **ac);
85 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
86  u32 bits_wanted,
87  struct ocfs2_alloc_context **ac);
88 
89 int ocfs2_claim_metadata(handle_t *handle,
90  struct ocfs2_alloc_context *ac,
91  u32 bits_wanted,
92  u64 *suballoc_loc,
93  u16 *suballoc_bit_start,
94  u32 *num_bits,
95  u64 *blkno_start);
96 int ocfs2_claim_new_inode(handle_t *handle,
97  struct inode *dir,
98  struct buffer_head *parent_fe_bh,
99  struct ocfs2_alloc_context *ac,
100  u64 *suballoc_loc,
101  u16 *suballoc_bit,
102  u64 *fe_blkno);
103 int ocfs2_claim_clusters(handle_t *handle,
104  struct ocfs2_alloc_context *ac,
105  u32 min_clusters,
106  u32 *cluster_start,
107  u32 *num_clusters);
108 /*
109  * Use this variant of ocfs2_claim_clusters to specify a maxiumum
110  * number of clusters smaller than the allocation reserved.
111  */
112 int __ocfs2_claim_clusters(handle_t *handle,
113  struct ocfs2_alloc_context *ac,
114  u32 min_clusters,
115  u32 max_clusters,
116  u32 *cluster_start,
117  u32 *num_clusters);
118 
119 int ocfs2_free_suballoc_bits(handle_t *handle,
120  struct inode *alloc_inode,
121  struct buffer_head *alloc_bh,
122  unsigned int start_bit,
123  u64 bg_blkno,
124  unsigned int count);
125 int ocfs2_free_dinode(handle_t *handle,
126  struct inode *inode_alloc_inode,
127  struct buffer_head *inode_alloc_bh,
128  struct ocfs2_dinode *di);
129 int ocfs2_free_clusters(handle_t *handle,
130  struct inode *bitmap_inode,
131  struct buffer_head *bitmap_bh,
132  u64 start_blk,
133  unsigned int num_clusters);
134 int ocfs2_release_clusters(handle_t *handle,
135  struct inode *bitmap_inode,
136  struct buffer_head *bitmap_bh,
137  u64 start_blk,
138  unsigned int num_clusters);
139 
140 static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
141 {
142  u64 group = block - (u64) bit;
143 
144  return group;
145 }
146 
147 static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
148  u64 bg_blkno)
149 {
150  /* This should work for all block group descriptors as only
151  * the 1st group descriptor of the cluster bitmap is
152  * different. */
153 
154  if (bg_blkno == osb->first_cluster_group_blkno)
155  return 0;
156 
157  /* the rest of the block groups are located at the beginning
158  * of their 1st cluster, so a direct translation just
159  * works. */
160  return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
161 }
162 
163 static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
164 {
165  struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
166  return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
167 }
168 
169 /* This is for local alloc ONLY. Others should use the task-specific
170  * apis above. */
171 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
172  struct ocfs2_alloc_context *ac);
173 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
174 
175 /* given a cluster offset, calculate which block group it belongs to
176  * and return that block offset. */
177 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
178 
179 /*
180  * By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
181  * finds a problem. A caller that wants to check a group descriptor
182  * without going readonly should read the block with ocfs2_read_block[s]()
183  * and then checking it with this function. This is only resize, really.
184  * Everyone else should be using ocfs2_read_group_descriptor().
185  */
186 int ocfs2_check_group_descriptor(struct super_block *sb,
187  struct ocfs2_dinode *di,
188  struct buffer_head *bh);
189 /*
190  * Read a group descriptor block into *bh. If *bh is NULL, a bh will be
191  * allocated. This is a cached read. The descriptor will be validated with
192  * ocfs2_validate_group_descriptor().
193  */
194 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
195  u64 gd_blkno, struct buffer_head **bh);
196 
197 int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
198  u32 clusters_to_add, u32 extents_to_split,
199  struct ocfs2_alloc_context **data_ac,
200  struct ocfs2_alloc_context **meta_ac);
201 
202 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);
203 
204 
205 
206 /*
207  * The following two interfaces are for ocfs2_create_inode_in_orphan().
208  */
209 int ocfs2_find_new_inode_loc(struct inode *dir,
210  struct buffer_head *parent_fe_bh,
211  struct ocfs2_alloc_context *ac,
212  u64 *fe_blkno);
213 
214 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
215  struct inode *dir,
216  struct ocfs2_alloc_context *ac,
217  u64 *suballoc_loc,
218  u16 *suballoc_bit,
219  u64 di_blkno);
220 
221 #endif /* _CHAINALLOC_H_ */
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