linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (c) 2004-2005 Silicon Graphics, Inc.

 * All Rights Reserved.

 */

#include "xfs.h"

#include "xfs_format.h"

#include "xfs_log_format.h"

#include "xfs_trans_resv.h"

#include "xfs_mount.h"

#include "xfs_da_format.h"

#include "xfs_da_btree.h"

#include "xfs_dir2.h"

#include "xfs_export.h"

#include "xfs_inode.h"

#include "xfs_trans.h"

#include "xfs_inode_item.h"

#include "xfs_trace.h"

#include "xfs_icache.h"

#include "xfs_log.h"

#include "xfs_pnfs.h"

​

/*

 * Note that we only accept fileids which are long enough rather than allow

 * the parent generation number to default to zero.  XFS considers zero a

 * valid generation number not an invalid/wildcard value.

 */

static int xfs_fileid_length(int fileid_type)

{

    switch (fileid_type) {

    case FILEID_INO32_GEN:

        return 2;

    case FILEID_INO32_GEN_PARENT:

        return 4;

    case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:

        return 3;

    case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:

        return 6;

    }

    return FILEID_INVALID;

}

​

STATIC int

xfs_fs_encode_fh(

    struct inode    *inode,

    __u32       *fh,

    int     *max_len,

    struct inode    *parent)

{

    struct fid      *fid = (struct fid *)fh;

    struct xfs_fid64    *fid64 = (struct xfs_fid64 *)fh;

    int         fileid_type;

    int         len;

​

    /* Directories don't need their parent encoded, they have ".." */

    if (!parent)

        fileid_type = FILEID_INO32_GEN;

    else

        fileid_type = FILEID_INO32_GEN_PARENT;

​

    /*

     * If the the filesystem may contain 64bit inode numbers, we need

     * to use larger file handles that can represent them.

     *

     * While we only allocate inodes that do not fit into 32 bits any

     * large enough filesystem may contain them, thus the slightly

     * confusing looking conditional below.

     */

    if (!(XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_SMALL_INUMS) ||

        (XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_32BITINODES))

        fileid_type |= XFS_FILEID_TYPE_64FLAG;

​

    /*

     * Only encode if there is enough space given.  In practice

     * this means we can't export a filesystem with 64bit inodes

     * over NFSv2 with the subtree_check export option; the other

     * seven combinations work.  The real answer is "don't use v2".

     */

    len = xfs_fileid_length(fileid_type);

    if (*max_len < len) {

        *max_len = len;

        return FILEID_INVALID;

    }

    *max_len = len;

​

    switch (fileid_type) {

    case FILEID_INO32_GEN_PARENT:

        fid->i32.parent_ino = XFS_I(parent)->i_ino;

        fid->i32.parent_gen = parent->i_generation;

        /*FALLTHRU*/

    case FILEID_INO32_GEN:

        fid->i32.ino = XFS_I(inode)->i_ino;