projects/linux·blob master · refs

285 lines · 6.3 KiB

1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * export.c
4 *
5 * Functions to facilitate NFS exporting
6 *
7 * Copyright (C) 2002, 2005 Oracle. All rights reserved.
8 */
9
10#include <linux/fs.h>
11#include <linux/types.h>
12
13#include <cluster/masklog.h>
14
15#include "ocfs2.h"
16
17#include "alloc.h"
18#include "dir.h"
19#include "dlmglue.h"
20#include "dcache.h"
21#include "export.h"
22#include "inode.h"
23
24#include "buffer_head_io.h"
25#include "suballoc.h"
26#include "ocfs2_trace.h"
27
28struct ocfs2_inode_handle
29{
30 u64 ih_blkno;
31 u32 ih_generation;
32};
33
34static struct dentry *ocfs2_get_dentry(struct super_block *sb,
35 struct ocfs2_inode_handle *handle)
36{
37 struct inode *inode;
38 struct ocfs2_super *osb = OCFS2_SB(sb);
39 u64 blkno = handle->ih_blkno;
40 int status, set;
41 struct dentry *result;
42
43 trace_ocfs2_get_dentry_begin(sb, handle, (unsigned long long)blkno);
44
45 if (blkno == 0) {
46 result = ERR_PTR(-ESTALE);
47 goto bail;
48 }
49
50 inode = ocfs2_ilookup(sb, blkno);
51 /*
52 * If the inode exists in memory, we only need to check it's
53 * generation number
54 */
55 if (inode)
56 goto check_gen;
57
58 /*
59 * This will synchronize us against ocfs2_delete_inode() on
60 * all nodes
61 */
62 status = ocfs2_nfs_sync_lock(osb, 1);
63 if (status < 0) {
64 mlog(ML_ERROR, "getting nfs sync lock(EX) failed %d\n", status);
65 goto check_err;
66 }
67
68 status = ocfs2_test_inode_bit(osb, blkno, &set);
69 if (status < 0) {
70 if (status == -EINVAL) {
71 /*
72 * The blkno NFS gave us doesn't even show up
73 * as an inode, we return -ESTALE to be
74 * nice
75 */
76 status = -ESTALE;
77 } else if (status != -ESTALE) {
78 mlog(ML_ERROR, "test inode bit failed %d\n", status);
79 }
80 goto unlock_nfs_sync;
81 }
82
83 trace_ocfs2_get_dentry_test_bit(status, set);
84 /* If the inode allocator bit is clear, this inode must be stale */
85 if (!set) {
86 status = -ESTALE;
87 goto unlock_nfs_sync;
88 }
89
90 inode = ocfs2_iget(osb, blkno, 0, 0);
91
92unlock_nfs_sync:
93 ocfs2_nfs_sync_unlock(osb, 1);
94
95check_err:
96 if (status < 0) {
97 if (status == -ESTALE) {
98 trace_ocfs2_get_dentry_stale((unsigned long long)blkno,
99 handle->ih_generation);
100 }
101 result = ERR_PTR(status);
102 goto bail;
103 }
104
105 if (IS_ERR(inode)) {
106 mlog_errno(PTR_ERR(inode));
107 result = ERR_CAST(inode);
108 goto bail;
109 }
110
111check_gen:
112 if (handle->ih_generation != inode->i_generation) {
113 trace_ocfs2_get_dentry_generation((unsigned long long)blkno,
114 handle->ih_generation,
115 inode->i_generation);
116 iput(inode);
117 result = ERR_PTR(-ESTALE);
118 goto bail;
119 }
120
121 result = d_obtain_alias(inode);
122 if (IS_ERR(result))
123 mlog_errno(PTR_ERR(result));
124
125bail:
126 trace_ocfs2_get_dentry_end(result);
127 return result;
128}
129
130static struct dentry *ocfs2_get_parent(struct dentry *child)
131{
132 int status;
133 u64 blkno;
134 struct dentry *parent;
135 struct inode *dir = d_inode(child);
136 int set;
137
138 trace_ocfs2_get_parent(child, child->d_name.len, child->d_name.name,
139 (unsigned long long)OCFS2_I(dir)->ip_blkno);
140
141 status = ocfs2_nfs_sync_lock(OCFS2_SB(dir->i_sb), 1);
142 if (status < 0) {
143 mlog(ML_ERROR, "getting nfs sync lock(EX) failed %d\n", status);
144 parent = ERR_PTR(status);
145 goto bail;
146 }
147
148 status = ocfs2_inode_lock(dir, NULL, 0);
149 if (status < 0) {
150 if (status != -ENOENT)
151 mlog_errno(status);
152 parent = ERR_PTR(status);
153 goto unlock_nfs_sync;
154 }
155
156 status = ocfs2_lookup_ino_from_name(dir, "..", 2, &blkno);
157 if (status < 0) {
158 parent = ERR_PTR(-ENOENT);
159 goto bail_unlock;
160 }
161
162 status = ocfs2_test_inode_bit(OCFS2_SB(dir->i_sb), blkno, &set);
163 if (status < 0) {
164 if (status == -EINVAL) {
165 status = -ESTALE;
166 } else if (status != -ESTALE) {
167 mlog(ML_ERROR, "test inode bit failed %d\n", status);
168 }
169 parent = ERR_PTR(status);
170 goto bail_unlock;
171 }
172
173 trace_ocfs2_get_dentry_test_bit(status, set);
174 if (!set) {
175 status = -ESTALE;
176 parent = ERR_PTR(status);
177 goto bail_unlock;
178 }
179
180 parent = d_obtain_alias(ocfs2_iget(OCFS2_SB(dir->i_sb), blkno, 0, 0));
181
182bail_unlock:
183 ocfs2_inode_unlock(dir, 0);
184
185unlock_nfs_sync:
186 ocfs2_nfs_sync_unlock(OCFS2_SB(dir->i_sb), 1);
187
188bail:
189 trace_ocfs2_get_parent_end(parent);
190
191 return parent;
192}
193
194static int ocfs2_encode_fh(struct inode *inode, u32 *fh_in, int *max_len,
195 struct inode *parent)
196{
197 int len = *max_len;
198 int type = 1;
199 u64 blkno;
200 u32 generation;
201 __le32 *fh = (__force __le32 *) fh_in;
202
203#ifdef TRACE_HOOKS_ARE_NOT_BRAINDEAD_IN_YOUR_OPINION
204#error "You go ahead and fix that mess, then. Somehow"
205 trace_ocfs2_encode_fh_begin(dentry, dentry->d_name.len,
206 dentry->d_name.name,
207 fh, len, connectable);
208#endif
209
210 if (parent && (len < 6)) {
211 *max_len = 6;
212 type = FILEID_INVALID;
213 goto bail;
214 } else if (len < 3) {
215 *max_len = 3;
216 type = FILEID_INVALID;
217 goto bail;
218 }
219
220 blkno = OCFS2_I(inode)->ip_blkno;
221 generation = inode->i_generation;
222
223 trace_ocfs2_encode_fh_self((unsigned long long)blkno, generation);
224
225 len = 3;
226 fh[0] = cpu_to_le32((u32)(blkno >> 32));
227 fh[1] = cpu_to_le32((u32)(blkno & 0xffffffff));
228 fh[2] = cpu_to_le32(generation);
229
230 if (parent) {
231 blkno = OCFS2_I(parent)->ip_blkno;
232 generation = parent->i_generation;
233
234 fh[3] = cpu_to_le32((u32)(blkno >> 32));
235 fh[4] = cpu_to_le32((u32)(blkno & 0xffffffff));
236 fh[5] = cpu_to_le32(generation);
237
238 len = 6;
239 type = 2;
240
241 trace_ocfs2_encode_fh_parent((unsigned long long)blkno,
242 generation);
243 }
244
245 *max_len = len;
246
247bail:
248 trace_ocfs2_encode_fh_type(type);
249 return type;
250}
251
252static struct dentry *ocfs2_fh_to_dentry(struct super_block *sb,
253 struct fid *fid, int fh_len, int fh_type)
254{
255 struct ocfs2_inode_handle handle;
256
257 if (fh_len < 3 || fh_type > 2)
258 return NULL;
259
260 handle.ih_blkno = (u64)le32_to_cpu((__force __le32)fid->raw[0]) << 32;
261 handle.ih_blkno |= (u64)le32_to_cpu((__force __le32)fid->raw[1]);
262 handle.ih_generation = le32_to_cpu((__force __le32)fid->raw[2]);
263 return ocfs2_get_dentry(sb, &handle);
264}
265
266static struct dentry *ocfs2_fh_to_parent(struct super_block *sb,
267 struct fid *fid, int fh_len, int fh_type)
268{
269 struct ocfs2_inode_handle parent;
270
271 if (fh_type != 2 || fh_len < 6)
272 return NULL;
273
274 parent.ih_blkno = (u64)le32_to_cpu((__force __le32)fid->raw[3]) << 32;
275 parent.ih_blkno |= (u64)le32_to_cpu((__force __le32)fid->raw[4]);
276 parent.ih_generation = le32_to_cpu((__force __le32)fid->raw[5]);
277 return ocfs2_get_dentry(sb, &parent);
278}
279
280const struct export_operations ocfs2_export_ops = {
281 .encode_fh = ocfs2_encode_fh,
282 .fh_to_dentry = ocfs2_fh_to_dentry,
283 .fh_to_parent = ocfs2_fh_to_parent,
284 .get_parent = ocfs2_get_parent,
285};