xref: /openbmc/linux/fs/gfs2/bmap.h (revision 25985edc)
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9 
10 #ifndef __BMAP_DOT_H__
11 #define __BMAP_DOT_H__
12 
13 #include "inode.h"
14 
15 struct inode;
16 struct gfs2_inode;
17 struct page;
18 
19 
20 /**
21  * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file
22  * @ip: the file
23  * @len: the number of bytes to be written to the file
24  * @data_blocks: returns the number of data blocks required
25  * @ind_blocks: returns the number of indirect blocks required
26  *
27  */
28 
29 static inline void gfs2_write_calc_reserv(const struct gfs2_inode *ip,
30 					  unsigned int len,
31 					  unsigned int *data_blocks,
32 					  unsigned int *ind_blocks)
33 {
34 	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
35 	unsigned int tmp;
36 
37 	BUG_ON(gfs2_is_dir(ip));
38 	*data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3;
39 	*ind_blocks = 3 * (sdp->sd_max_height - 1);
40 
41 	for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) {
42 		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
43 		*ind_blocks += tmp;
44 	}
45 }
46 
47 extern int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page);
48 extern int gfs2_block_map(struct inode *inode, sector_t lblock,
49 			  struct buffer_head *bh, int create);
50 extern int gfs2_extent_map(struct inode *inode, u64 lblock, int *new,
51 			   u64 *dblock, unsigned *extlen);
52 extern int gfs2_setattr_size(struct inode *inode, u64 size);
53 extern void gfs2_trim_blocks(struct inode *inode);
54 extern int gfs2_truncatei_resume(struct gfs2_inode *ip);
55 extern int gfs2_file_dealloc(struct gfs2_inode *ip);
56 extern int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
57 				     unsigned int len);
58 
59 #endif /* __BMAP_DOT_H__ */
60