Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 | /*
* Copyright (c) 2004-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_types.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_export.h"
#include "xfs_vnodeops.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_vfsops.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 255; /* invalid */
}
STATIC int
xfs_fs_encode_fh(
struct dentry *dentry,
__u32 *fh,
int *max_len,
int connectable)
{
struct fid *fid = (struct fid *)fh;
struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh;
struct inode *inode = dentry->d_inode;
int fileid_type;
int len;
/* Directories don't need their parent encoded, they have ".." */
if (S_ISDIR(inode->i_mode) || !connectable)
fileid_type = FILEID_INO32_GEN;
else
fileid_type = FILEID_INO32_GEN_PARENT;
/* filesystem may contain 64bit inode numbers */
if (!(XFS_M(inode->i_sb)->m_flags & XFS_MOUNT_SMALL_INUMS))
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)
return 255;
*max_len = len;
switch (fileid_type) {
case FILEID_INO32_GEN_PARENT:
spin_lock(&dentry->d_lock);
fid->i32.parent_ino = dentry->d_parent->d_inode->i_ino;
fid->i32.parent_gen = dentry->d_parent->d_inode->i_generation;
spin_unlock(&dentry->d_lock);
/*FALLTHRU*/
case FILEID_INO32_GEN:
fid->i32.ino = inode->i_ino;
fid->i32.gen = inode->i_generation;
break;
case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
spin_lock(&dentry->d_lock);
fid64->parent_ino = dentry->d_parent->d_inode->i_ino;
fid64->parent_gen = dentry->d_parent->d_inode->i_generation;
spin_unlock(&dentry->d_lock);
/*FALLTHRU*/
case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
fid64->ino = inode->i_ino;
fid64->gen = inode->i_generation;
break;
}
return fileid_type;
}
STATIC struct inode *
xfs_nfs_get_inode(
struct super_block *sb,
u64 ino,
u32 generation)
{
xfs_mount_t *mp = XFS_M(sb);
xfs_inode_t *ip;
int error;
/*
* NFS can sometimes send requests for ino 0. Fail them gracefully.
*/
if (ino == 0)
return ERR_PTR(-ESTALE);
error = xfs_iget(mp, NULL, ino, 0, XFS_ILOCK_SHARED, &ip, 0);
if (error)
return ERR_PTR(-error);
if (!ip)
return ERR_PTR(-EIO);
if (ip->i_d.di_gen != generation) {
xfs_iput_new(ip, XFS_ILOCK_SHARED);
return ERR_PTR(-ENOENT);
}
xfs_iunlock(ip, XFS_ILOCK_SHARED);
return VFS_I(ip);
}
STATIC struct dentry *
xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
int fh_len, int fileid_type)
{
struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
struct inode *inode = NULL;
struct dentry *result;
if (fh_len < xfs_fileid_length(fileid_type))
return NULL;
switch (fileid_type) {
case FILEID_INO32_GEN_PARENT:
case FILEID_INO32_GEN:
inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen);
break;
case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen);
break;
}
if (!inode)
return NULL;
if (IS_ERR(inode))
return ERR_CAST(inode);
result = d_alloc_anon(inode);
if (!result) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
return result;
}
STATIC struct dentry *
xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid,
int fh_len, int fileid_type)
{
struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
struct inode *inode = NULL;
struct dentry *result;
switch (fileid_type) {
case FILEID_INO32_GEN_PARENT:
inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino,
fid->i32.parent_gen);
break;
case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
inode = xfs_nfs_get_inode(sb, fid64->parent_ino,
fid64->parent_gen);
break;
}
if (!inode)
return NULL;
if (IS_ERR(inode))
return ERR_CAST(inode);
result = d_alloc_anon(inode);
if (!result) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
return result;
}
STATIC struct dentry *
xfs_fs_get_parent(
struct dentry *child)
{
int error;
struct xfs_inode *cip;
struct dentry *parent;
error = xfs_lookup(XFS_I(child->d_inode), &xfs_name_dotdot, &cip, NULL);
if (unlikely(error))
return ERR_PTR(-error);
parent = d_alloc_anon(VFS_I(cip));
if (unlikely(!parent)) {
iput(VFS_I(cip));
return ERR_PTR(-ENOMEM);
}
return parent;
}
const struct export_operations xfs_export_operations = {
.encode_fh = xfs_fs_encode_fh,
.fh_to_dentry = xfs_fs_fh_to_dentry,
.fh_to_parent = xfs_fs_fh_to_parent,
.get_parent = xfs_fs_get_parent,
};
|