1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * NFS protocol definitions
4  *
5  * This file contains constants mostly for Version 2 of the protocol,
6  * but also has a couple of NFSv3 bits in (notably the error codes).
7  */
8 #ifndef _LINUX_NFS_H
9 #define _LINUX_NFS_H
10 
11 #include <linux/cred.h>
12 #include <linux/sunrpc/auth.h>
13 #include <linux/sunrpc/msg_prot.h>
14 #include <linux/string.h>
15 #include <linux/crc32.h>
16 #include <uapi/linux/nfs.h>
17 
18 /* The LOCALIO program is entirely private to Linux and is
19  * NOT part of the uapi.
20  */
21 #define NFS_LOCALIO_PROGRAM		400122
22 #define LOCALIOPROC_NULL		0
23 #define LOCALIOPROC_UUID_IS_LOCAL	1
24 
25 /*
26  * This is the kernel NFS client file handle representation
27  */
28 #define NFS_MAXFHSIZE		128
29 struct nfs_fh {
30 	unsigned short		size;
31 	unsigned char		data[NFS_MAXFHSIZE];
32 };
33 
34 /*
35  * Returns a zero iff the size and data fields match.
36  * Checks only "size" bytes in the data field.
37  */
nfs_compare_fh(const struct nfs_fh * a,const struct nfs_fh * b)38 static inline int nfs_compare_fh(const struct nfs_fh *a, const struct nfs_fh *b)
39 {
40 	return a->size != b->size || memcmp(a->data, b->data, a->size) != 0;
41 }
42 
nfs_copy_fh(struct nfs_fh * target,const struct nfs_fh * source)43 static inline void nfs_copy_fh(struct nfs_fh *target, const struct nfs_fh *source)
44 {
45 	target->size = source->size;
46 	memcpy(target->data, source->data, source->size);
47 }
48 
49 enum nfs3_stable_how {
50 	NFS_UNSTABLE = 0,
51 	NFS_DATA_SYNC = 1,
52 	NFS_FILE_SYNC = 2,
53 
54 	/* used by direct.c to mark verf as invalid */
55 	NFS_INVALID_STABLE_HOW = -1
56 };
57 
58 #ifdef CONFIG_CRC32
59 /**
60  * nfs_fhandle_hash - calculate the crc32 hash for the filehandle
61  * @fh - pointer to filehandle
62  *
63  * returns a crc32 hash for the filehandle that is compatible with
64  * the one displayed by "wireshark".
65  */
nfs_fhandle_hash(const struct nfs_fh * fh)66 static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
67 {
68 	return ~crc32_le(0xFFFFFFFF, &fh->data[0], fh->size);
69 }
70 #else /* CONFIG_CRC32 */
nfs_fhandle_hash(const struct nfs_fh * fh)71 static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)
72 {
73 	return 0;
74 }
75 #endif /* CONFIG_CRC32 */
76 #endif /* _LINUX_NFS_H */
77