xref: /linux/fs/gfs2/bmap.h (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
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 <linux/iomap.h>
14 
15 #include "inode.h"
16 
17 struct inode;
18 struct gfs2_inode;
19 struct page;
20 
21 
22 /**
23  * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file
24  * @ip: the file
25  * @len: the number of bytes to be written to the file
26  * @data_blocks: returns the number of data blocks required
27  * @ind_blocks: returns the number of indirect blocks required
28  *
29  */
30 
31 static inline void gfs2_write_calc_reserv(const struct gfs2_inode *ip,
32 					  unsigned int len,
33 					  unsigned int *data_blocks,
34 					  unsigned int *ind_blocks)
35 {
36 	const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
37 	unsigned int tmp;
38 
39 	BUG_ON(gfs2_is_dir(ip));
40 	*data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3;
41 	*ind_blocks = 3 * (sdp->sd_max_height - 1);
42 
43 	for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) {
44 		tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
45 		*ind_blocks += tmp;
46 	}
47 }
48 
49 extern const struct iomap_ops gfs2_iomap_ops;
50 
51 extern int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page);
52 extern int gfs2_block_map(struct inode *inode, sector_t lblock,
53 			  struct buffer_head *bh, int create);
54 extern int gfs2_iomap_get_alloc(struct inode *inode, loff_t pos, loff_t length,
55 				struct iomap *iomap);
56 extern int gfs2_extent_map(struct inode *inode, u64 lblock, int *new,
57 			   u64 *dblock, unsigned *extlen);
58 extern int gfs2_setattr_size(struct inode *inode, u64 size);
59 extern void gfs2_trim_blocks(struct inode *inode);
60 extern int gfs2_truncatei_resume(struct gfs2_inode *ip);
61 extern int gfs2_file_dealloc(struct gfs2_inode *ip);
62 extern int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
63 				     unsigned int len);
64 extern int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd);
65 extern void gfs2_free_journal_extents(struct gfs2_jdesc *jd);
66 extern int __gfs2_punch_hole(struct file *file, loff_t offset, loff_t length);
67 
68 #endif /* __BMAP_DOT_H__ */
69