include/linux/nfs.h

   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/sunrpc/msg_prot.h>
  12 #include <linux/string.h>
  13 #include <uapi/linux/nfs.h>
  14
  15 /*
  16  * This is the kernel NFS client file handle representation
  17  */
  18 #define NFS_MAXFHSIZE           128
  19 struct nfs_fh {
  20         unsigned short          size;
  21         unsigned char           data[NFS_MAXFHSIZE];
  22 };
  23
  24 /*
  25  * Returns a zero iff the size and data fields match.
  26  * Checks only "size" bytes in the data field.
  27  */
  28 static inline int nfs_compare_fh(const struct nfs_fh *a, const struct nfs_fh *b)
  29 {
  30         return a->size != b->size || memcmp(a->data, b->data, a->size) != 0;
  31 }
  32
  33 static inline void nfs_copy_fh(struct nfs_fh *target, const struct nfs_fh *source)
  34 {
  35         target->size = source->size;
  36         memcpy(target->data, source->data, source->size);
  37 }
  38
  39
  40 /*
  41  * This is really a general kernel constant, but since nothing like
  42  * this is defined in the kernel headers, I have to do it here.
  43  */
  44 #define NFS_OFFSET_MAX          ((__s64)((~(__u64)0) >> 1))
  45
  46
  47 enum nfs3_stable_how {
  48         NFS_UNSTABLE = 0,
  49         NFS_DATA_SYNC = 1,
  50         NFS_FILE_SYNC = 2,
  51
  52         /* used by direct.c to mark verf as invalid */
  53         NFS_INVALID_STABLE_HOW = -1
  54 };
  55 #endif /* _LINUX_NFS_H */