xref: /linux/fs/ocfs2/suballoc.h (revision 0da85d1e38b4c186d2248f0239b72d465f5b406c)
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_disable_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_alloc_dinode_update_counts(struct inode *inode,
90 			 handle_t *handle,
91 			 struct buffer_head *di_bh,
92 			 u32 num_bits,
93 			 u16 chain);
94 void ocfs2_rollback_alloc_dinode_counts(struct inode *inode,
95 			 struct buffer_head *di_bh,
96 			 u32 num_bits,
97 			 u16 chain);
98 int ocfs2_block_group_set_bits(handle_t *handle,
99 			 struct inode *alloc_inode,
100 			 struct ocfs2_group_desc *bg,
101 			 struct buffer_head *group_bh,
102 			 unsigned int bit_off,
103 			 unsigned int num_bits);
104 
105 int ocfs2_claim_metadata(handle_t *handle,
106 			 struct ocfs2_alloc_context *ac,
107 			 u32 bits_wanted,
108 			 u64 *suballoc_loc,
109 			 u16 *suballoc_bit_start,
110 			 u32 *num_bits,
111 			 u64 *blkno_start);
112 int ocfs2_claim_new_inode(handle_t *handle,
113 			  struct inode *dir,
114 			  struct buffer_head *parent_fe_bh,
115 			  struct ocfs2_alloc_context *ac,
116 			  u64 *suballoc_loc,
117 			  u16 *suballoc_bit,
118 			  u64 *fe_blkno);
119 int ocfs2_claim_clusters(handle_t *handle,
120 			 struct ocfs2_alloc_context *ac,
121 			 u32 min_clusters,
122 			 u32 *cluster_start,
123 			 u32 *num_clusters);
124 /*
125  * Use this variant of ocfs2_claim_clusters to specify a maxiumum
126  * number of clusters smaller than the allocation reserved.
127  */
128 int __ocfs2_claim_clusters(handle_t *handle,
129 			   struct ocfs2_alloc_context *ac,
130 			   u32 min_clusters,
131 			   u32 max_clusters,
132 			   u32 *cluster_start,
133 			   u32 *num_clusters);
134 
135 int ocfs2_free_suballoc_bits(handle_t *handle,
136 			     struct inode *alloc_inode,
137 			     struct buffer_head *alloc_bh,
138 			     unsigned int start_bit,
139 			     u64 bg_blkno,
140 			     unsigned int count);
141 int ocfs2_free_dinode(handle_t *handle,
142 		      struct inode *inode_alloc_inode,
143 		      struct buffer_head *inode_alloc_bh,
144 		      struct ocfs2_dinode *di);
145 int ocfs2_free_clusters(handle_t *handle,
146 			struct inode *bitmap_inode,
147 			struct buffer_head *bitmap_bh,
148 			u64 start_blk,
149 			unsigned int num_clusters);
150 int ocfs2_release_clusters(handle_t *handle,
151 			   struct inode *bitmap_inode,
152 			   struct buffer_head *bitmap_bh,
153 			   u64 start_blk,
154 			   unsigned int num_clusters);
155 
156 static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
157 {
158 	u64 group = block - (u64) bit;
159 
160 	return group;
161 }
162 
163 static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
164 					  u64 bg_blkno)
165 {
166 	/* This should work for all block group descriptors as only
167 	 * the 1st group descriptor of the cluster bitmap is
168 	 * different. */
169 
170 	if (bg_blkno == osb->first_cluster_group_blkno)
171 		return 0;
172 
173 	/* the rest of the block groups are located at the beginning
174 	 * of their 1st cluster, so a direct translation just
175 	 * works. */
176 	return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
177 }
178 
179 static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
180 {
181 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
182 	return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
183 }
184 
185 /* This is for local alloc ONLY. Others should use the task-specific
186  * apis above. */
187 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
188 				      struct ocfs2_alloc_context *ac);
189 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
190 
191 /* given a cluster offset, calculate which block group it belongs to
192  * and return that block offset. */
193 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
194 
195 /*
196  * By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
197  * finds a problem.  A caller that wants to check a group descriptor
198  * without going readonly should read the block with ocfs2_read_block[s]()
199  * and then checking it with this function.  This is only resize, really.
200  * Everyone else should be using ocfs2_read_group_descriptor().
201  */
202 int ocfs2_check_group_descriptor(struct super_block *sb,
203 				 struct ocfs2_dinode *di,
204 				 struct buffer_head *bh);
205 /*
206  * Read a group descriptor block into *bh.  If *bh is NULL, a bh will be
207  * allocated.  This is a cached read.  The descriptor will be validated with
208  * ocfs2_validate_group_descriptor().
209  */
210 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
211 				u64 gd_blkno, struct buffer_head **bh);
212 
213 int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
214 			  u32 clusters_to_add, u32 extents_to_split,
215 			  struct ocfs2_alloc_context **data_ac,
216 			  struct ocfs2_alloc_context **meta_ac);
217 
218 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);
219 
220 
221 
222 /*
223  * The following two interfaces are for ocfs2_create_inode_in_orphan().
224  */
225 int ocfs2_find_new_inode_loc(struct inode *dir,
226 			     struct buffer_head *parent_fe_bh,
227 			     struct ocfs2_alloc_context *ac,
228 			     u64 *fe_blkno);
229 
230 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
231 				 struct inode *dir,
232 				 struct ocfs2_alloc_context *ac,
233 				 u64 *suballoc_loc,
234 				 u16 *suballoc_bit,
235 				 u64 di_blkno);
236 
237 #endif /* _CHAINALLOC_H_ */
238