xref: /linux/fs/gfs2/dir.h (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
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 __DIR_DOT_H__
11 #define __DIR_DOT_H__
12 
13 #include <linux/dcache.h>
14 #include <linux/crc32.h>
15 
16 struct inode;
17 struct gfs2_inode;
18 struct gfs2_inum;
19 
20 struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *filename);
21 int gfs2_dir_check(struct inode *dir, const struct qstr *filename,
22 		   const struct gfs2_inode *ip);
23 int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
24 		 const struct gfs2_inode *ip, unsigned int type);
25 int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *filename);
26 int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque,
27 		  filldir_t filldir);
28 int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
29 		   const struct gfs2_inode *nip, unsigned int new_type);
30 
31 int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);
32 
33 int gfs2_diradd_alloc_required(struct inode *dir,
34 			       const struct qstr *filename);
35 int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
36 			    struct buffer_head **bhp);
37 
38 static inline u32 gfs2_disk_hash(const char *data, int len)
39 {
40         return crc32_le((u32)~0, data, len) ^ (u32)~0;
41 }
42 
43 
44 static inline void gfs2_str2qstr(struct qstr *name, const char *fname)
45 {
46 	name->name = fname;
47 	name->len = strlen(fname);
48 	name->hash = gfs2_disk_hash(name->name, name->len);
49 }
50 
51 /* N.B. This probably ought to take inum & type as args as well */
52 static inline void gfs2_qstr2dirent(const struct qstr *name, u16 reclen, struct gfs2_dirent *dent)
53 {
54 	dent->de_inum.no_addr = cpu_to_be64(0);
55 	dent->de_inum.no_formal_ino = cpu_to_be64(0);
56 	dent->de_hash = cpu_to_be32(name->hash);
57 	dent->de_rec_len = cpu_to_be16(reclen);
58 	dent->de_name_len = cpu_to_be16(name->len);
59 	dent->de_type = cpu_to_be16(0);
60 	memset(dent->__pad, 0, sizeof(dent->__pad));
61 	memcpy(dent + 1, name->name, name->len);
62 }
63 
64 #endif /* __DIR_DOT_H__ */
65