d09d64b2981023574ed612a4f234bda13d0dd5ae
[linux-2.6.git] / fs / ocfs2 / refcounttree.h
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * refcounttree.h
5  *
6  * Copyright (C) 2009 Oracle.  All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public
10  * License version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License for more details.
16  */
17 #ifndef OCFS2_REFCOUNTTREE_H
18 #define OCFS2_REFCOUNTTREE_H
19
20 struct ocfs2_refcount_tree {
21         struct rb_node rf_node;
22         u64 rf_blkno;
23         u32 rf_generation;
24         struct rw_semaphore rf_sem;
25         struct ocfs2_lock_res rf_lockres;
26         struct kref rf_getcnt;
27         int rf_removed;
28
29         /* the following 4 fields are used by caching_info. */
30         struct ocfs2_caching_info rf_ci;
31         spinlock_t rf_lock;
32         struct mutex rf_io_mutex;
33         struct super_block *rf_sb;
34 };
35
36 void ocfs2_purge_refcount_trees(struct ocfs2_super *osb);
37 int ocfs2_lock_refcount_tree(struct ocfs2_super *osb, u64 ref_blkno, int rw,
38                              struct ocfs2_refcount_tree **tree,
39                              struct buffer_head **ref_bh);
40 void ocfs2_unlock_refcount_tree(struct ocfs2_super *osb,
41                                 struct ocfs2_refcount_tree *tree,
42                                 int rw);
43
44 int ocfs2_decrease_refcount(struct inode *inode,
45                             handle_t *handle, u32 cpos, u32 len,
46                             struct ocfs2_alloc_context *meta_ac,
47                             struct ocfs2_cached_dealloc_ctxt *dealloc,
48                             int delete);
49 int ocfs2_prepare_refcount_change_for_del(struct inode *inode,
50                                           struct buffer_head *di_bh,
51                                           u64 phys_blkno,
52                                           u32 clusters,
53                                           int *credits,
54                                           struct ocfs2_alloc_context **meta_ac);
55 int ocfs2_refcount_cow(struct inode *inode, struct buffer_head *di_bh,
56                        u32 cpos, u32 write_len, u32 max_cpos);
57
58 typedef int (ocfs2_post_refcount_func)(struct inode *inode,
59                                        handle_t *handle,
60                                        void *para);
61 /*
62  * Some refcount caller need to do more work after we modify the data b-tree
63  * during refcount operation(including CoW and add refcount flag), and make the
64  * transaction complete. So it must give us this structure so that we can do it
65  * within our transaction.
66  *
67  */
68 struct ocfs2_post_refcount {
69         int credits;                    /* credits it need for journal. */
70         ocfs2_post_refcount_func *func; /* real function. */
71         void *para;
72 };
73
74 int ocfs2_refcounted_xattr_delete_need(struct inode *inode,
75                                        struct ocfs2_caching_info *ref_ci,
76                                        struct buffer_head *ref_root_bh,
77                                        struct ocfs2_xattr_value_root *xv,
78                                        int *meta_add, int *credits);
79 int ocfs2_refcount_cow_xattr(struct inode *inode,
80                              struct ocfs2_dinode *di,
81                              struct ocfs2_xattr_value_buf *vb,
82                              struct ocfs2_refcount_tree *ref_tree,
83                              struct buffer_head *ref_root_bh,
84                              u32 cpos, u32 write_len,
85                              struct ocfs2_post_refcount *post);
86 #endif /* OCFS2_REFCOUNTTREE_H */