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26#include <linux/fs.h>
27#include <linux/types.h>
28
29#define MLOG_MASK_PREFIX ML_EXPORT
30#include <cluster/masklog.h>
31
32#include "ocfs2.h"
33
34#include "dir.h"
35#include "dlmglue.h"
36#include "dcache.h"
37#include "export.h"
38#include "inode.h"
39
40#include "buffer_head_io.h"
41
42struct ocfs2_inode_handle
43{
44 u64 ih_blkno;
45 u32 ih_generation;
46};
47
48static struct dentry *ocfs2_get_dentry(struct super_block *sb, void *vobjp)
49{
50 struct ocfs2_inode_handle *handle = vobjp;
51 struct inode *inode;
52 struct dentry *result;
53
54 mlog_entry("(0x%p, 0x%p)\n", sb, handle);
55
56 if (handle->ih_blkno == 0) {
57 mlog_errno(-ESTALE);
58 return ERR_PTR(-ESTALE);
59 }
60
61 inode = ocfs2_iget(OCFS2_SB(sb), handle->ih_blkno, 0);
62
63 if (IS_ERR(inode))
64 return (void *)inode;
65
66 if (handle->ih_generation != inode->i_generation) {
67 iput(inode);
68 return ERR_PTR(-ESTALE);
69 }
70
71 result = d_alloc_anon(inode);
72
73 if (!result) {
74 iput(inode);
75 mlog_errno(-ENOMEM);
76 return ERR_PTR(-ENOMEM);
77 }
78 result->d_op = &ocfs2_dentry_ops;
79
80 mlog_exit_ptr(result);
81 return result;
82}
83
84static struct dentry *ocfs2_get_parent(struct dentry *child)
85{
86 int status;
87 u64 blkno;
88 struct dentry *parent;
89 struct inode *inode;
90 struct inode *dir = child->d_inode;
91 struct buffer_head *dirent_bh = NULL;
92 struct ocfs2_dir_entry *dirent;
93
94 mlog_entry("(0x%p, '%.*s')\n", child,
95 child->d_name.len, child->d_name.name);
96
97 mlog(0, "find parent of directory %llu\n",
98 (unsigned long long)OCFS2_I(dir)->ip_blkno);
99
100 status = ocfs2_meta_lock(dir, NULL, 0);
101 if (status < 0) {
102 if (status != -ENOENT)
103 mlog_errno(status);
104 parent = ERR_PTR(status);
105 goto bail;
106 }
107
108 status = ocfs2_find_files_on_disk("..", 2, &blkno, dir, &dirent_bh,
109 &dirent);
110 if (status < 0) {
111 parent = ERR_PTR(-ENOENT);
112 goto bail_unlock;
113 }
114
115 inode = ocfs2_iget(OCFS2_SB(dir->i_sb), blkno, 0);
116 if (IS_ERR(inode)) {
117 mlog(ML_ERROR, "Unable to create inode %llu\n",
118 (unsigned long long)blkno);
119 parent = ERR_PTR(-EACCES);
120 goto bail_unlock;
121 }
122
123 parent = d_alloc_anon(inode);
124 if (!parent) {
125 iput(inode);
126 parent = ERR_PTR(-ENOMEM);
127 }
128
129 parent->d_op = &ocfs2_dentry_ops;
130
131bail_unlock:
132 ocfs2_meta_unlock(dir, 0);
133
134 if (dirent_bh)
135 brelse(dirent_bh);
136
137bail:
138 mlog_exit_ptr(parent);
139
140 return parent;
141}
142
143static int ocfs2_encode_fh(struct dentry *dentry, __be32 *fh, int *max_len,
144 int connectable)
145{
146 struct inode *inode = dentry->d_inode;
147 int len = *max_len;
148 int type = 1;
149 u64 blkno;
150 u32 generation;
151
152 mlog_entry("(0x%p, '%.*s', 0x%p, %d, %d)\n", dentry,
153 dentry->d_name.len, dentry->d_name.name,
154 fh, len, connectable);
155
156 if (len < 3 || (connectable && len < 6)) {
157 mlog(ML_ERROR, "fh buffer is too small for encoding\n");
158 type = 255;
159 goto bail;
160 }
161
162 blkno = OCFS2_I(inode)->ip_blkno;
163 generation = inode->i_generation;
164
165 mlog(0, "Encoding fh: blkno: %llu, generation: %u\n",
166 (unsigned long long)blkno, generation);
167
168 len = 3;
169 fh[0] = cpu_to_le32((u32)(blkno >> 32));
170 fh[1] = cpu_to_le32((u32)(blkno & 0xffffffff));
171 fh[2] = cpu_to_le32(generation);
172
173 if (connectable && !S_ISDIR(inode->i_mode)) {
174 struct inode *parent;
175
176 spin_lock(&dentry->d_lock);
177
178 parent = dentry->d_parent->d_inode;
179 blkno = OCFS2_I(parent)->ip_blkno;
180 generation = parent->i_generation;
181
182 fh[3] = cpu_to_le32((u32)(blkno >> 32));
183 fh[4] = cpu_to_le32((u32)(blkno & 0xffffffff));
184 fh[5] = cpu_to_le32(generation);
185
186 spin_unlock(&dentry->d_lock);
187
188 len = 6;
189 type = 2;
190
191 mlog(0, "Encoding parent: blkno: %llu, generation: %u\n",
192 (unsigned long long)blkno, generation);
193 }
194
195 *max_len = len;
196
197bail:
198 mlog_exit(type);
199 return type;
200}
201
202static struct dentry *ocfs2_decode_fh(struct super_block *sb, __be32 *fh,
203 int fh_len, int fileid_type,
204 int (*acceptable)(void *context,
205 struct dentry *de),
206 void *context)
207{
208 struct ocfs2_inode_handle handle, parent;
209 struct dentry *ret = NULL;
210
211 mlog_entry("(0x%p, 0x%p, %d, %d, 0x%p, 0x%p)\n",
212 sb, fh, fh_len, fileid_type, acceptable, context);
213
214 if (fh_len < 3 || fileid_type > 2)
215 goto bail;
216
217 if (fileid_type == 2) {
218 if (fh_len < 6)
219 goto bail;
220
221 parent.ih_blkno = (u64)le32_to_cpu(fh[3]) << 32;
222 parent.ih_blkno |= (u64)le32_to_cpu(fh[4]);
223 parent.ih_generation = le32_to_cpu(fh[5]);
224
225 mlog(0, "Decoding parent: blkno: %llu, generation: %u\n",
226 (unsigned long long)parent.ih_blkno,
227 parent.ih_generation);
228 }
229
230 handle.ih_blkno = (u64)le32_to_cpu(fh[0]) << 32;
231 handle.ih_blkno |= (u64)le32_to_cpu(fh[1]);
232 handle.ih_generation = le32_to_cpu(fh[2]);
233
234 mlog(0, "Encoding fh: blkno: %llu, generation: %u\n",
235 (unsigned long long)handle.ih_blkno, handle.ih_generation);
236
237 ret = ocfs2_export_ops.find_exported_dentry(sb, &handle, &parent,
238 acceptable, context);
239
240bail:
241 mlog_exit_ptr(ret);
242 return ret;
243}
244
245struct export_operations ocfs2_export_ops = {
246 .decode_fh = ocfs2_decode_fh,
247 .encode_fh = ocfs2_encode_fh,
248
249 .get_parent = ocfs2_get_parent,
250 .get_dentry = ocfs2_get_dentry,
251};
252
