xref: /openbmc/linux/fs/ocfs2/alloc.h (revision 2ae99a60)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * alloc.h
5  *
6  * Function prototypes
7  *
8  * Copyright (C) 2002, 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 OCFS2_ALLOC_H
27 #define OCFS2_ALLOC_H
28 
29 struct ocfs2_alloc_context;
30 int ocfs2_insert_extent(struct ocfs2_super *osb,
31 			handle_t *handle,
32 			struct inode *inode,
33 			struct buffer_head *fe_bh,
34 			u32 cpos,
35 			u64 start_blk,
36 			u32 new_clusters,
37 			u8 flags,
38 			struct ocfs2_alloc_context *meta_ac);
39 struct ocfs2_cached_dealloc_ctxt;
40 int ocfs2_mark_extent_written(struct inode *inode, struct buffer_head *di_bh,
41 			      handle_t *handle, u32 cpos, u32 len, u32 phys,
42 			      struct ocfs2_alloc_context *meta_ac,
43 			      struct ocfs2_cached_dealloc_ctxt *dealloc);
44 int ocfs2_num_free_extents(struct ocfs2_super *osb,
45 			   struct inode *inode,
46 			   struct ocfs2_dinode *fe);
47 /* how many new metadata chunks would an allocation need at maximum? */
48 static inline int ocfs2_extend_meta_needed(struct ocfs2_dinode *fe)
49 {
50 	/*
51 	 * Rather than do all the work of determining how much we need
52 	 * (involves a ton of reads and locks), just ask for the
53 	 * maximal limit.  That's a tree depth shift.  So, one block for
54 	 * level of the tree (current l_tree_depth), one block for the
55 	 * new tree_depth==0 extent_block, and one block at the new
56 	 * top-of-the tree.
57 	 */
58 	return le16_to_cpu(fe->id2.i_list.l_tree_depth) + 2;
59 }
60 
61 int ocfs2_truncate_log_init(struct ocfs2_super *osb);
62 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb);
63 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
64 				       int cancel);
65 int ocfs2_flush_truncate_log(struct ocfs2_super *osb);
66 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb,
67 				      int slot_num,
68 				      struct ocfs2_dinode **tl_copy);
69 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb,
70 					 struct ocfs2_dinode *tl_copy);
71 
72 /*
73  * Process local structure which describes the block unlinks done
74  * during an operation. This is populated via
75  * ocfs2_cache_block_dealloc().
76  *
77  * ocfs2_run_deallocs() should be called after the potentially
78  * de-allocating routines. No journal handles should be open, and most
79  * locks should have been dropped.
80  */
81 struct ocfs2_cached_dealloc_ctxt {
82 	struct ocfs2_per_slot_free_list		*c_first_suballocator;
83 };
84 static inline void ocfs2_init_dealloc_ctxt(struct ocfs2_cached_dealloc_ctxt *c)
85 {
86 	c->c_first_suballocator = NULL;
87 }
88 int ocfs2_run_deallocs(struct ocfs2_super *osb,
89 		       struct ocfs2_cached_dealloc_ctxt *ctxt);
90 
91 struct ocfs2_truncate_context {
92 	struct ocfs2_cached_dealloc_ctxt tc_dealloc;
93 	int tc_ext_alloc_locked; /* is it cluster locked? */
94 	/* these get destroyed once it's passed to ocfs2_commit_truncate. */
95 	struct buffer_head *tc_last_eb_bh;
96 };
97 
98 int ocfs2_zero_tail_for_truncate(struct inode *inode, handle_t *handle,
99 				 u64 new_i_size);
100 int ocfs2_prepare_truncate(struct ocfs2_super *osb,
101 			   struct inode *inode,
102 			   struct buffer_head *fe_bh,
103 			   struct ocfs2_truncate_context **tc);
104 int ocfs2_commit_truncate(struct ocfs2_super *osb,
105 			  struct inode *inode,
106 			  struct buffer_head *fe_bh,
107 			  struct ocfs2_truncate_context *tc);
108 
109 int ocfs2_find_leaf(struct inode *inode, struct ocfs2_extent_list *root_el,
110 		    u32 cpos, struct buffer_head **leaf_bh);
111 int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster);
112 
113 /*
114  * Helper function to look at the # of clusters in an extent record.
115  */
116 static inline unsigned int ocfs2_rec_clusters(struct ocfs2_extent_list *el,
117 					      struct ocfs2_extent_rec *rec)
118 {
119 	/*
120 	 * Cluster count in extent records is slightly different
121 	 * between interior nodes and leaf nodes. This is to support
122 	 * unwritten extents which need a flags field in leaf node
123 	 * records, thus shrinking the available space for a clusters
124 	 * field.
125 	 */
126 	if (el->l_tree_depth)
127 		return le32_to_cpu(rec->e_int_clusters);
128 	else
129 		return le16_to_cpu(rec->e_leaf_clusters);
130 }
131 
132 #endif /* OCFS2_ALLOC_H */
133