xref: /openbmc/linux/fs/gfs2/dir.h (revision adb80490)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
5  */
6 
7 #ifndef __DIR_DOT_H__
8 #define __DIR_DOT_H__
9 
10 #include <linux/dcache.h>
11 #include <linux/crc32.h>
12 
13 struct inode;
14 struct gfs2_inode;
15 struct gfs2_inum;
16 struct buffer_head;
17 struct gfs2_dirent;
18 
19 struct gfs2_diradd {
20 	unsigned nr_blocks;
21 	struct gfs2_dirent *dent;
22 	struct buffer_head *bh;
23 	int save_loc;
24 };
25 
26 extern struct inode *gfs2_dir_search(struct inode *dir,
27 				     const struct qstr *filename,
28 				     bool fail_on_exist);
29 extern int gfs2_dir_check(struct inode *dir, const struct qstr *filename,
30 			  const struct gfs2_inode *ip);
31 extern int gfs2_dir_add(struct inode *inode, const struct qstr *filename,
32 			const struct gfs2_inode *ip, struct gfs2_diradd *da);
33 static inline void gfs2_dir_no_add(struct gfs2_diradd *da)
34 {
35 	if (da->bh)
36 		brelse(da->bh);
37 	da->bh = NULL;
38 }
39 extern int gfs2_dir_del(struct gfs2_inode *dip, const struct dentry *dentry);
40 extern int gfs2_dir_read(struct inode *inode, struct dir_context *ctx,
41 			 struct file_ra_state *f_ra);
42 extern int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
43 			  const struct gfs2_inode *nip, unsigned int new_type);
44 
45 extern int gfs2_dir_exhash_dealloc(struct gfs2_inode *dip);
46 
47 extern int gfs2_diradd_alloc_required(struct inode *dir,
48 				      const struct qstr *filename,
49 				      struct gfs2_diradd *da);
50 extern int gfs2_dir_get_new_buffer(struct gfs2_inode *ip, u64 block,
51 				   struct buffer_head **bhp);
52 extern void gfs2_dir_hash_inval(struct gfs2_inode *ip);
53 
54 static inline u32 gfs2_disk_hash(const char *data, int len)
55 {
56         return crc32_le((u32)~0, data, len) ^ (u32)~0;
57 }
58 
59 
60 static inline void gfs2_str2qstr(struct qstr *name, const char *fname)
61 {
62 	name->name = fname;
63 	name->len = strlen(fname);
64 	name->hash = gfs2_disk_hash(name->name, name->len);
65 }
66 
67 /* N.B. This probably ought to take inum & type as args as well */
68 static inline void gfs2_qstr2dirent(const struct qstr *name, u16 reclen, struct gfs2_dirent *dent)
69 {
70 	dent->de_inum.no_addr = cpu_to_be64(0);
71 	dent->de_inum.no_formal_ino = cpu_to_be64(0);
72 	dent->de_hash = cpu_to_be32(name->hash);
73 	dent->de_rec_len = cpu_to_be16(reclen);
74 	dent->de_name_len = cpu_to_be16(name->len);
75 	dent->de_type = cpu_to_be16(0);
76 	memset(dent->__pad, 0, sizeof(dent->__pad));
77 	memcpy(dent + 1, name->name, name->len);
78 }
79 
80 extern struct qstr gfs2_qdot;
81 extern struct qstr gfs2_qdotdot;
82 
83 #endif /* __DIR_DOT_H__ */
84