Commit 1264a2f0 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: refactor code for calculating the crc32 hash of a filehandle 



We want to be able to display the crc32 hash of the filehandle in
tracepoints.

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent c2dd1378

fs/nfs/inode.c

+1 −2
Original line number Diff line number Diff line
@@ -38,7 +38,6 @@ 
#include <linux/slab.h>

#include <linux/compat.h>

#include <linux/freezer.h>

#include <linux/crc32.h>



#include <asm/uaccess.h>
@@ -1190,7 +1189,7 @@ u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh) 
{

	/* wireshark uses 32-bit AUTODIN crc and does a bitwise

	 * not on the result */

	return ~crc32(0xFFFFFFFF, &fh->data[0], fh->size);

	return nfs_fhandle_hash(fh);

}



/*

fs/nfs/internal.h

+20 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include "nfs4_fs.h"

#include <linux/mount.h>

#include <linux/security.h>

#include <linux/crc32.h>



#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
@@ -574,3 +575,22 @@ u64 nfs_timespec_to_change_attr(const struct timespec *ts) 
{

	return ((u64)ts->tv_sec << 30) + ts->tv_nsec;

}



#ifdef CONFIG_CRC32

/**

 * nfs_fhandle_hash - calculate the crc32 hash for the filehandle

 * @fh - pointer to filehandle

 *

 * returns a crc32 hash for the filehandle that is compatible with

 * the one displayed by "wireshark".

 */

static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)

{

	return ~crc32_le(0xFFFFFFFF, &fh->data[0], fh->size);

}

#else

static inline u32 nfs_fhandle_hash(const struct nfs_fh *fh)

{

	return 0;

}

#endif