ia64/linux-2.6.18-xen.hg

view fs/ocfs2/export.c @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * export.c
5 *
6 * Functions to facilitate NFS exporting
7 *
8 * Copyright (C) 2002, 2005 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 */
26 #include <linux/fs.h>
27 #include <linux/types.h>
29 #define MLOG_MASK_PREFIX ML_EXPORT
30 #include <cluster/masklog.h>
32 #include "ocfs2.h"
34 #include "dir.h"
35 #include "dlmglue.h"
36 #include "export.h"
37 #include "inode.h"
39 #include "buffer_head_io.h"
41 struct ocfs2_inode_handle
42 {
43 u64 ih_blkno;
44 u32 ih_generation;
45 };
47 static struct dentry *ocfs2_get_dentry(struct super_block *sb, void *vobjp)
48 {
49 struct ocfs2_inode_handle *handle = vobjp;
50 struct inode *inode;
51 struct dentry *result;
53 mlog_entry("(0x%p, 0x%p)\n", sb, handle);
55 if (handle->ih_blkno == 0) {
56 mlog_errno(-ESTALE);
57 return ERR_PTR(-ESTALE);
58 }
60 inode = ocfs2_iget(OCFS2_SB(sb), handle->ih_blkno);
62 if (IS_ERR(inode)) {
63 mlog_errno(PTR_ERR(inode));
64 return (void *)inode;
65 }
67 if (handle->ih_generation != inode->i_generation) {
68 iput(inode);
69 mlog_errno(-ESTALE);
70 return ERR_PTR(-ESTALE);
71 }
73 result = d_alloc_anon(inode);
75 if (!result) {
76 iput(inode);
77 mlog_errno(-ENOMEM);
78 return ERR_PTR(-ENOMEM);
79 }
81 mlog_exit_ptr(result);
82 return result;
83 }
85 static struct dentry *ocfs2_get_parent(struct dentry *child)
86 {
87 int status;
88 u64 blkno;
89 struct dentry *parent;
90 struct inode *inode;
91 struct inode *dir = child->d_inode;
92 struct buffer_head *dirent_bh = NULL;
93 struct ocfs2_dir_entry *dirent;
95 mlog_entry("(0x%p, '%.*s')\n", child,
96 child->d_name.len, child->d_name.name);
98 mlog(0, "find parent of directory %llu\n",
99 (unsigned long long)OCFS2_I(dir)->ip_blkno);
101 status = ocfs2_meta_lock(dir, NULL, NULL, 0);
102 if (status < 0) {
103 if (status != -ENOENT)
104 mlog_errno(status);
105 parent = ERR_PTR(status);
106 goto bail;
107 }
109 status = ocfs2_find_files_on_disk("..", 2, &blkno, dir, &dirent_bh,
110 &dirent);
111 if (status < 0) {
112 parent = ERR_PTR(-ENOENT);
113 goto bail_unlock;
114 }
116 inode = ocfs2_iget(OCFS2_SB(dir->i_sb), blkno);
117 if (IS_ERR(inode)) {
118 mlog(ML_ERROR, "Unable to create inode %llu\n",
119 (unsigned long long)blkno);
120 parent = ERR_PTR(-EACCES);
121 goto bail_unlock;
122 }
124 parent = d_alloc_anon(inode);
125 if (!parent) {
126 iput(inode);
127 parent = ERR_PTR(-ENOMEM);
128 }
130 bail_unlock:
131 ocfs2_meta_unlock(dir, 0);
133 if (dirent_bh)
134 brelse(dirent_bh);
136 bail:
137 mlog_exit_ptr(parent);
139 return parent;
140 }
142 static int ocfs2_encode_fh(struct dentry *dentry, __be32 *fh, int *max_len,
143 int connectable)
144 {
145 struct inode *inode = dentry->d_inode;
146 int len = *max_len;
147 int type = 1;
148 u64 blkno;
149 u32 generation;
151 mlog_entry("(0x%p, '%.*s', 0x%p, %d, %d)\n", dentry,
152 dentry->d_name.len, dentry->d_name.name,
153 fh, len, connectable);
155 if (len < 3 || (connectable && len < 6)) {
156 mlog(ML_ERROR, "fh buffer is too small for encoding\n");
157 type = 255;
158 goto bail;
159 }
161 blkno = OCFS2_I(inode)->ip_blkno;
162 generation = inode->i_generation;
164 mlog(0, "Encoding fh: blkno: %llu, generation: %u\n",
165 (unsigned long long)blkno, generation);
167 len = 3;
168 fh[0] = cpu_to_le32((u32)(blkno >> 32));
169 fh[1] = cpu_to_le32((u32)(blkno & 0xffffffff));
170 fh[2] = cpu_to_le32(generation);
172 if (connectable && !S_ISDIR(inode->i_mode)) {
173 struct inode *parent;
175 spin_lock(&dentry->d_lock);
177 parent = dentry->d_parent->d_inode;
178 blkno = OCFS2_I(parent)->ip_blkno;
179 generation = parent->i_generation;
181 fh[3] = cpu_to_le32((u32)(blkno >> 32));
182 fh[4] = cpu_to_le32((u32)(blkno & 0xffffffff));
183 fh[5] = cpu_to_le32(generation);
185 spin_unlock(&dentry->d_lock);
187 len = 6;
188 type = 2;
190 mlog(0, "Encoding parent: blkno: %llu, generation: %u\n",
191 (unsigned long long)blkno, generation);
192 }
194 *max_len = len;
196 bail:
197 mlog_exit(type);
198 return type;
199 }
201 static struct dentry *ocfs2_decode_fh(struct super_block *sb, __be32 *fh,
202 int fh_len, int fileid_type,
203 int (*acceptable)(void *context,
204 struct dentry *de),
205 void *context)
206 {
207 struct ocfs2_inode_handle handle, parent;
208 struct dentry *ret = NULL;
210 mlog_entry("(0x%p, 0x%p, %d, %d, 0x%p, 0x%p)\n",
211 sb, fh, fh_len, fileid_type, acceptable, context);
213 if (fh_len < 3 || fileid_type > 2)
214 goto bail;
216 if (fileid_type == 2) {
217 if (fh_len < 6)
218 goto bail;
220 parent.ih_blkno = (u64)le32_to_cpu(fh[3]) << 32;
221 parent.ih_blkno |= (u64)le32_to_cpu(fh[4]);
222 parent.ih_generation = le32_to_cpu(fh[5]);
224 mlog(0, "Decoding parent: blkno: %llu, generation: %u\n",
225 (unsigned long long)parent.ih_blkno,
226 parent.ih_generation);
227 }
229 handle.ih_blkno = (u64)le32_to_cpu(fh[0]) << 32;
230 handle.ih_blkno |= (u64)le32_to_cpu(fh[1]);
231 handle.ih_generation = le32_to_cpu(fh[2]);
233 mlog(0, "Encoding fh: blkno: %llu, generation: %u\n",
234 (unsigned long long)handle.ih_blkno, handle.ih_generation);
236 ret = ocfs2_export_ops.find_exported_dentry(sb, &handle, &parent,
237 acceptable, context);
239 bail:
240 mlog_exit_ptr(ret);
241 return ret;
242 }
244 struct export_operations ocfs2_export_ops = {
245 .decode_fh = ocfs2_decode_fh,
246 .encode_fh = ocfs2_encode_fh,
248 .get_parent = ocfs2_get_parent,
249 .get_dentry = ocfs2_get_dentry,
250 };