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1#include <linux/ceph/ceph_debug.h>
2
3#include <linux/exportfs.h>
4#include <linux/slab.h>
5#include <asm/unaligned.h>
6
7#include "super.h"
8#include "mds_client.h"
9
10/*
11 * Basic fh
12 */
13struct ceph_nfs_fh {
14 u64 ino;
15} __attribute__ ((packed));
16
17/*
18 * Larger fh that includes parent ino.
19 */
20struct ceph_nfs_confh {
21 u64 ino, parent_ino;
22} __attribute__ ((packed));
23
24static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
25 struct inode *parent_inode)
26{
27 int type;
28 struct ceph_nfs_fh *fh = (void *)rawfh;
29 struct ceph_nfs_confh *cfh = (void *)rawfh;
30 int connected_handle_length = sizeof(*cfh)/4;
31 int handle_length = sizeof(*fh)/4;
32
33 /* don't re-export snaps */
34 if (ceph_snap(inode) != CEPH_NOSNAP)
35 return -EINVAL;
36
37 if (parent_inode && (*max_len < connected_handle_length)) {
38 *max_len = connected_handle_length;
39 return FILEID_INVALID;
40 } else if (*max_len < handle_length) {
41 *max_len = handle_length;
42 return FILEID_INVALID;
43 }
44
45 if (parent_inode) {
46 dout("encode_fh %llx with parent %llx\n",
47 ceph_ino(inode), ceph_ino(parent_inode));
48 cfh->ino = ceph_ino(inode);
49 cfh->parent_ino = ceph_ino(parent_inode);
50 *max_len = connected_handle_length;
51 type = FILEID_INO32_GEN_PARENT;
52 } else {
53 dout("encode_fh %llx\n", ceph_ino(inode));
54 fh->ino = ceph_ino(inode);
55 *max_len = handle_length;
56 type = FILEID_INO32_GEN;
57 }
58 return type;
59}
60
61static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
62{
63 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
64 struct inode *inode;
65 struct dentry *dentry;
66 struct ceph_vino vino;
67 int err;
68
69 vino.ino = ino;
70 vino.snap = CEPH_NOSNAP;
71 inode = ceph_find_inode(sb, vino);
72 if (!inode) {
73 struct ceph_mds_request *req;
74
75 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
76 USE_ANY_MDS);
77 if (IS_ERR(req))
78 return ERR_CAST(req);
79
80 req->r_ino1 = vino;
81 req->r_num_caps = 1;
82 err = ceph_mdsc_do_request(mdsc, NULL, req);
83 inode = req->r_target_inode;
84 if (inode)
85 ihold(inode);
86 ceph_mdsc_put_request(req);
87 if (!inode)
88 return ERR_PTR(-ESTALE);
89 }
90
91 dentry = d_obtain_alias(inode);
92 if (IS_ERR(dentry)) {
93 iput(inode);
94 return dentry;
95 }
96 err = ceph_init_dentry(dentry);
97 if (err < 0) {
98 dput(dentry);
99 return ERR_PTR(err);
100 }
101 dout("__fh_to_dentry %llx %p dentry %p\n", ino, inode, dentry);
102 return dentry;
103}
104
105/*
106 * convert regular fh to dentry
107 */
108static struct dentry *ceph_fh_to_dentry(struct super_block *sb,
109 struct fid *fid,
110 int fh_len, int fh_type)
111{
112 struct ceph_nfs_fh *fh = (void *)fid->raw;
113
114 if (fh_type != FILEID_INO32_GEN &&
115 fh_type != FILEID_INO32_GEN_PARENT)
116 return NULL;
117 if (fh_len < sizeof(*fh) / 4)
118 return NULL;
119
120 dout("fh_to_dentry %llx\n", fh->ino);
121 return __fh_to_dentry(sb, fh->ino);
122}
123
124static struct dentry *__get_parent(struct super_block *sb,
125 struct dentry *child, u64 ino)
126{
127 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
128 struct ceph_mds_request *req;
129 struct inode *inode;
130 struct dentry *dentry;
131 int err;
132
133 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT,
134 USE_ANY_MDS);
135 if (IS_ERR(req))
136 return ERR_CAST(req);
137
138 if (child) {
139 req->r_inode = child->d_inode;
140 ihold(child->d_inode);
141 } else {
142 req->r_ino1 = (struct ceph_vino) {
143 .ino = ino,
144 .snap = CEPH_NOSNAP,
145 };
146 }
147 req->r_num_caps = 1;
148 err = ceph_mdsc_do_request(mdsc, NULL, req);
149 inode = req->r_target_inode;
150 if (inode)
151 ihold(inode);
152 ceph_mdsc_put_request(req);
153 if (!inode)
154 return ERR_PTR(-ENOENT);
155
156 dentry = d_obtain_alias(inode);
157 if (IS_ERR(dentry)) {
158 iput(inode);
159 return dentry;
160 }
161 err = ceph_init_dentry(dentry);
162 if (err < 0) {
163 dput(dentry);
164 return ERR_PTR(err);
165 }
166 dout("__get_parent ino %llx parent %p ino %llx.%llx\n",
167 child ? ceph_ino(child->d_inode) : ino,
168 dentry, ceph_vinop(inode));
169 return dentry;
170}
171
172struct dentry *ceph_get_parent(struct dentry *child)
173{
174 /* don't re-export snaps */
175 if (ceph_snap(child->d_inode) != CEPH_NOSNAP)
176 return ERR_PTR(-EINVAL);
177
178 dout("get_parent %p ino %llx.%llx\n",
179 child, ceph_vinop(child->d_inode));
180 return __get_parent(child->d_sb, child, 0);
181}
182
183/*
184 * convert regular fh to parent
185 */
186static struct dentry *ceph_fh_to_parent(struct super_block *sb,
187 struct fid *fid,
188 int fh_len, int fh_type)
189{
190 struct ceph_nfs_confh *cfh = (void *)fid->raw;
191 struct dentry *dentry;
192
193 if (fh_type != FILEID_INO32_GEN_PARENT)
194 return NULL;
195 if (fh_len < sizeof(*cfh) / 4)
196 return NULL;
197
198 dout("fh_to_parent %llx\n", cfh->parent_ino);
199 dentry = __get_parent(sb, NULL, cfh->ino);
200 if (IS_ERR(dentry) && PTR_ERR(dentry) == -ENOENT)
201 dentry = __fh_to_dentry(sb, cfh->parent_ino);
202 return dentry;
203}
204
205static int ceph_get_name(struct dentry *parent, char *name,
206 struct dentry *child)
207{
208 struct ceph_mds_client *mdsc;
209 struct ceph_mds_request *req;
210 int err;
211
212 mdsc = ceph_inode_to_client(child->d_inode)->mdsc;
213 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME,
214 USE_ANY_MDS);
215 if (IS_ERR(req))
216 return PTR_ERR(req);
217
218 mutex_lock(&parent->d_inode->i_mutex);
219
220 req->r_inode = child->d_inode;
221 ihold(child->d_inode);
222 req->r_ino2 = ceph_vino(parent->d_inode);
223 req->r_locked_dir = parent->d_inode;
224 req->r_num_caps = 2;
225 err = ceph_mdsc_do_request(mdsc, NULL, req);
226
227 mutex_unlock(&parent->d_inode->i_mutex);
228
229 if (!err) {
230 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
231 memcpy(name, rinfo->dname, rinfo->dname_len);
232 name[rinfo->dname_len] = 0;
233 dout("get_name %p ino %llx.%llx name %s\n",
234 child, ceph_vinop(child->d_inode), name);
235 } else {
236 dout("get_name %p ino %llx.%llx err %d\n",
237 child, ceph_vinop(child->d_inode), err);
238 }
239
240 ceph_mdsc_put_request(req);
241 return err;
242}
243
244const struct export_operations ceph_export_ops = {
245 .encode_fh = ceph_encode_fh,
246 .fh_to_dentry = ceph_fh_to_dentry,
247 .fh_to_parent = ceph_fh_to_parent,
248 .get_parent = ceph_get_parent,
249 .get_name = ceph_get_name,
250};
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/ceph/ceph_debug.h>
3
4#include <linux/exportfs.h>
5#include <linux/slab.h>
6#include <linux/unaligned.h>
7
8#include "super.h"
9#include "mds_client.h"
10#include "crypto.h"
11
12/*
13 * Basic fh
14 */
15struct ceph_nfs_fh {
16 u64 ino;
17} __attribute__ ((packed));
18
19/*
20 * Larger fh that includes parent ino.
21 */
22struct ceph_nfs_confh {
23 u64 ino, parent_ino;
24} __attribute__ ((packed));
25
26/*
27 * fh for snapped inode
28 */
29struct ceph_nfs_snapfh {
30 u64 ino;
31 u64 snapid;
32 u64 parent_ino;
33 u32 hash;
34} __attribute__ ((packed));
35
36static int ceph_encode_snapfh(struct inode *inode, u32 *rawfh, int *max_len,
37 struct inode *parent_inode)
38{
39 struct ceph_client *cl = ceph_inode_to_client(inode);
40 static const int snap_handle_length =
41 sizeof(struct ceph_nfs_snapfh) >> 2;
42 struct ceph_nfs_snapfh *sfh = (void *)rawfh;
43 u64 snapid = ceph_snap(inode);
44 int ret;
45 bool no_parent = true;
46
47 if (*max_len < snap_handle_length) {
48 *max_len = snap_handle_length;
49 ret = FILEID_INVALID;
50 goto out;
51 }
52
53 ret = -EINVAL;
54 if (snapid != CEPH_SNAPDIR) {
55 struct inode *dir;
56 struct dentry *dentry = d_find_alias(inode);
57 if (!dentry)
58 goto out;
59
60 rcu_read_lock();
61 dir = d_inode_rcu(dentry->d_parent);
62 if (ceph_snap(dir) != CEPH_SNAPDIR) {
63 sfh->parent_ino = ceph_ino(dir);
64 sfh->hash = ceph_dentry_hash(dir, dentry);
65 no_parent = false;
66 }
67 rcu_read_unlock();
68 dput(dentry);
69 }
70
71 if (no_parent) {
72 if (!S_ISDIR(inode->i_mode))
73 goto out;
74 sfh->parent_ino = sfh->ino;
75 sfh->hash = 0;
76 }
77 sfh->ino = ceph_ino(inode);
78 sfh->snapid = snapid;
79
80 *max_len = snap_handle_length;
81 ret = FILEID_BTRFS_WITH_PARENT;
82out:
83 doutc(cl, "%p %llx.%llx ret=%d\n", inode, ceph_vinop(inode), ret);
84 return ret;
85}
86
87static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
88 struct inode *parent_inode)
89{
90 struct ceph_client *cl = ceph_inode_to_client(inode);
91 static const int handle_length =
92 sizeof(struct ceph_nfs_fh) >> 2;
93 static const int connected_handle_length =
94 sizeof(struct ceph_nfs_confh) >> 2;
95 int type;
96
97 if (ceph_snap(inode) != CEPH_NOSNAP)
98 return ceph_encode_snapfh(inode, rawfh, max_len, parent_inode);
99
100 if (parent_inode && (*max_len < connected_handle_length)) {
101 *max_len = connected_handle_length;
102 return FILEID_INVALID;
103 } else if (*max_len < handle_length) {
104 *max_len = handle_length;
105 return FILEID_INVALID;
106 }
107
108 if (parent_inode) {
109 struct ceph_nfs_confh *cfh = (void *)rawfh;
110 doutc(cl, "%p %llx.%llx with parent %p %llx.%llx\n", inode,
111 ceph_vinop(inode), parent_inode, ceph_vinop(parent_inode));
112 cfh->ino = ceph_ino(inode);
113 cfh->parent_ino = ceph_ino(parent_inode);
114 *max_len = connected_handle_length;
115 type = FILEID_INO32_GEN_PARENT;
116 } else {
117 struct ceph_nfs_fh *fh = (void *)rawfh;
118 doutc(cl, "%p %llx.%llx\n", inode, ceph_vinop(inode));
119 fh->ino = ceph_ino(inode);
120 *max_len = handle_length;
121 type = FILEID_INO32_GEN;
122 }
123 return type;
124}
125
126static struct inode *__lookup_inode(struct super_block *sb, u64 ino)
127{
128 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb)->mdsc;
129 struct inode *inode;
130 struct ceph_vino vino;
131 int err;
132
133 vino.ino = ino;
134 vino.snap = CEPH_NOSNAP;
135
136 if (ceph_vino_is_reserved(vino))
137 return ERR_PTR(-ESTALE);
138
139 inode = ceph_find_inode(sb, vino);
140 if (!inode) {
141 struct ceph_mds_request *req;
142 int mask;
143
144 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
145 USE_ANY_MDS);
146 if (IS_ERR(req))
147 return ERR_CAST(req);
148
149 mask = CEPH_STAT_CAP_INODE;
150 if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
151 mask |= CEPH_CAP_XATTR_SHARED;
152 req->r_args.lookupino.mask = cpu_to_le32(mask);
153
154 req->r_ino1 = vino;
155 req->r_num_caps = 1;
156 err = ceph_mdsc_do_request(mdsc, NULL, req);
157 inode = req->r_target_inode;
158 if (inode)
159 ihold(inode);
160 ceph_mdsc_put_request(req);
161 if (!inode)
162 return err < 0 ? ERR_PTR(err) : ERR_PTR(-ESTALE);
163 } else {
164 if (ceph_inode_is_shutdown(inode)) {
165 iput(inode);
166 return ERR_PTR(-ESTALE);
167 }
168 }
169 return inode;
170}
171
172struct inode *ceph_lookup_inode(struct super_block *sb, u64 ino)
173{
174 struct inode *inode = __lookup_inode(sb, ino);
175 if (IS_ERR(inode))
176 return inode;
177 if (inode->i_nlink == 0) {
178 iput(inode);
179 return ERR_PTR(-ESTALE);
180 }
181 return inode;
182}
183
184static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
185{
186 struct inode *inode = __lookup_inode(sb, ino);
187 struct ceph_inode_info *ci = ceph_inode(inode);
188 int err;
189
190 if (IS_ERR(inode))
191 return ERR_CAST(inode);
192 /* We need LINK caps to reliably check i_nlink */
193 err = ceph_do_getattr(inode, CEPH_CAP_LINK_SHARED, false);
194 if (err) {
195 iput(inode);
196 return ERR_PTR(err);
197 }
198 /* -ESTALE if inode as been unlinked and no file is open */
199 if ((inode->i_nlink == 0) && !__ceph_is_file_opened(ci)) {
200 iput(inode);
201 return ERR_PTR(-ESTALE);
202 }
203 return d_obtain_alias(inode);
204}
205
206static struct dentry *__snapfh_to_dentry(struct super_block *sb,
207 struct ceph_nfs_snapfh *sfh,
208 bool want_parent)
209{
210 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb)->mdsc;
211 struct ceph_client *cl = mdsc->fsc->client;
212 struct ceph_mds_request *req;
213 struct inode *inode;
214 struct ceph_vino vino;
215 int mask;
216 int err;
217 bool unlinked = false;
218
219 if (want_parent) {
220 vino.ino = sfh->parent_ino;
221 if (sfh->snapid == CEPH_SNAPDIR)
222 vino.snap = CEPH_NOSNAP;
223 else if (sfh->ino == sfh->parent_ino)
224 vino.snap = CEPH_SNAPDIR;
225 else
226 vino.snap = sfh->snapid;
227 } else {
228 vino.ino = sfh->ino;
229 vino.snap = sfh->snapid;
230 }
231
232 if (ceph_vino_is_reserved(vino))
233 return ERR_PTR(-ESTALE);
234
235 inode = ceph_find_inode(sb, vino);
236 if (inode) {
237 if (ceph_inode_is_shutdown(inode)) {
238 iput(inode);
239 return ERR_PTR(-ESTALE);
240 }
241 return d_obtain_alias(inode);
242 }
243
244 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
245 USE_ANY_MDS);
246 if (IS_ERR(req))
247 return ERR_CAST(req);
248
249 mask = CEPH_STAT_CAP_INODE;
250 if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
251 mask |= CEPH_CAP_XATTR_SHARED;
252 req->r_args.lookupino.mask = cpu_to_le32(mask);
253 if (vino.snap < CEPH_NOSNAP) {
254 req->r_args.lookupino.snapid = cpu_to_le64(vino.snap);
255 if (!want_parent && sfh->ino != sfh->parent_ino) {
256 req->r_args.lookupino.parent =
257 cpu_to_le64(sfh->parent_ino);
258 req->r_args.lookupino.hash =
259 cpu_to_le32(sfh->hash);
260 }
261 }
262
263 req->r_ino1 = vino;
264 req->r_num_caps = 1;
265 err = ceph_mdsc_do_request(mdsc, NULL, req);
266 inode = req->r_target_inode;
267 if (inode) {
268 if (vino.snap == CEPH_SNAPDIR) {
269 if (inode->i_nlink == 0)
270 unlinked = true;
271 inode = ceph_get_snapdir(inode);
272 } else if (ceph_snap(inode) == vino.snap) {
273 ihold(inode);
274 } else {
275 /* mds does not support lookup snapped inode */
276 inode = ERR_PTR(-EOPNOTSUPP);
277 }
278 } else {
279 inode = ERR_PTR(-ESTALE);
280 }
281 ceph_mdsc_put_request(req);
282
283 if (want_parent) {
284 doutc(cl, "%llx.%llx\n err=%d\n", vino.ino, vino.snap, err);
285 } else {
286 doutc(cl, "%llx.%llx parent %llx hash %x err=%d", vino.ino,
287 vino.snap, sfh->parent_ino, sfh->hash, err);
288 }
289 /* see comments in ceph_get_parent() */
290 return unlinked ? d_obtain_root(inode) : d_obtain_alias(inode);
291}
292
293/*
294 * convert regular fh to dentry
295 */
296static struct dentry *ceph_fh_to_dentry(struct super_block *sb,
297 struct fid *fid,
298 int fh_len, int fh_type)
299{
300 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb);
301 struct ceph_nfs_fh *fh = (void *)fid->raw;
302
303 if (fh_type == FILEID_BTRFS_WITH_PARENT) {
304 struct ceph_nfs_snapfh *sfh = (void *)fid->raw;
305 return __snapfh_to_dentry(sb, sfh, false);
306 }
307
308 if (fh_type != FILEID_INO32_GEN &&
309 fh_type != FILEID_INO32_GEN_PARENT)
310 return NULL;
311 if (fh_len < sizeof(*fh) / 4)
312 return NULL;
313
314 doutc(fsc->client, "%llx\n", fh->ino);
315 return __fh_to_dentry(sb, fh->ino);
316}
317
318static struct dentry *__get_parent(struct super_block *sb,
319 struct dentry *child, u64 ino)
320{
321 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb)->mdsc;
322 struct ceph_mds_request *req;
323 struct inode *inode;
324 int mask;
325 int err;
326
327 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT,
328 USE_ANY_MDS);
329 if (IS_ERR(req))
330 return ERR_CAST(req);
331
332 if (child) {
333 req->r_inode = d_inode(child);
334 ihold(d_inode(child));
335 } else {
336 req->r_ino1 = (struct ceph_vino) {
337 .ino = ino,
338 .snap = CEPH_NOSNAP,
339 };
340 }
341
342 mask = CEPH_STAT_CAP_INODE;
343 if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
344 mask |= CEPH_CAP_XATTR_SHARED;
345 req->r_args.getattr.mask = cpu_to_le32(mask);
346
347 req->r_num_caps = 1;
348 err = ceph_mdsc_do_request(mdsc, NULL, req);
349 if (err) {
350 ceph_mdsc_put_request(req);
351 return ERR_PTR(err);
352 }
353
354 inode = req->r_target_inode;
355 if (inode)
356 ihold(inode);
357 ceph_mdsc_put_request(req);
358 if (!inode)
359 return ERR_PTR(-ENOENT);
360
361 return d_obtain_alias(inode);
362}
363
364static struct dentry *ceph_get_parent(struct dentry *child)
365{
366 struct inode *inode = d_inode(child);
367 struct ceph_client *cl = ceph_inode_to_client(inode);
368 struct dentry *dn;
369
370 if (ceph_snap(inode) != CEPH_NOSNAP) {
371 struct inode* dir;
372 bool unlinked = false;
373 /* do not support non-directory */
374 if (!d_is_dir(child)) {
375 dn = ERR_PTR(-EINVAL);
376 goto out;
377 }
378 dir = __lookup_inode(inode->i_sb, ceph_ino(inode));
379 if (IS_ERR(dir)) {
380 dn = ERR_CAST(dir);
381 goto out;
382 }
383 /* There can be multiple paths to access snapped inode.
384 * For simplicity, treat snapdir of head inode as parent */
385 if (ceph_snap(inode) != CEPH_SNAPDIR) {
386 struct inode *snapdir = ceph_get_snapdir(dir);
387 if (dir->i_nlink == 0)
388 unlinked = true;
389 iput(dir);
390 if (IS_ERR(snapdir)) {
391 dn = ERR_CAST(snapdir);
392 goto out;
393 }
394 dir = snapdir;
395 }
396 /* If directory has already been deleted, further get_parent
397 * will fail. Do not mark snapdir dentry as disconnected,
398 * this prevents exportfs from doing further get_parent. */
399 if (unlinked)
400 dn = d_obtain_root(dir);
401 else
402 dn = d_obtain_alias(dir);
403 } else {
404 dn = __get_parent(child->d_sb, child, 0);
405 }
406out:
407 doutc(cl, "child %p %p %llx.%llx err=%ld\n", child, inode,
408 ceph_vinop(inode), (long)PTR_ERR_OR_ZERO(dn));
409 return dn;
410}
411
412/*
413 * convert regular fh to parent
414 */
415static struct dentry *ceph_fh_to_parent(struct super_block *sb,
416 struct fid *fid,
417 int fh_len, int fh_type)
418{
419 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb);
420 struct ceph_nfs_confh *cfh = (void *)fid->raw;
421 struct dentry *dentry;
422
423 if (fh_type == FILEID_BTRFS_WITH_PARENT) {
424 struct ceph_nfs_snapfh *sfh = (void *)fid->raw;
425 return __snapfh_to_dentry(sb, sfh, true);
426 }
427
428 if (fh_type != FILEID_INO32_GEN_PARENT)
429 return NULL;
430 if (fh_len < sizeof(*cfh) / 4)
431 return NULL;
432
433 doutc(fsc->client, "%llx\n", cfh->parent_ino);
434 dentry = __get_parent(sb, NULL, cfh->ino);
435 if (unlikely(dentry == ERR_PTR(-ENOENT)))
436 dentry = __fh_to_dentry(sb, cfh->parent_ino);
437 return dentry;
438}
439
440static int __get_snap_name(struct dentry *parent, char *name,
441 struct dentry *child)
442{
443 struct inode *inode = d_inode(child);
444 struct inode *dir = d_inode(parent);
445 struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
446 struct ceph_mds_request *req = NULL;
447 char *last_name = NULL;
448 unsigned next_offset = 2;
449 int err = -EINVAL;
450
451 if (ceph_ino(inode) != ceph_ino(dir))
452 goto out;
453 if (ceph_snap(inode) == CEPH_SNAPDIR) {
454 if (ceph_snap(dir) == CEPH_NOSNAP) {
455 /*
456 * .get_name() from struct export_operations
457 * assumes that its 'name' parameter is pointing
458 * to a NAME_MAX+1 sized buffer
459 */
460 strscpy(name, fsc->mount_options->snapdir_name,
461 NAME_MAX + 1);
462 err = 0;
463 }
464 goto out;
465 }
466 if (ceph_snap(dir) != CEPH_SNAPDIR)
467 goto out;
468
469 while (1) {
470 struct ceph_mds_reply_info_parsed *rinfo;
471 struct ceph_mds_reply_dir_entry *rde;
472 int i;
473
474 req = ceph_mdsc_create_request(fsc->mdsc, CEPH_MDS_OP_LSSNAP,
475 USE_AUTH_MDS);
476 if (IS_ERR(req)) {
477 err = PTR_ERR(req);
478 req = NULL;
479 goto out;
480 }
481 err = ceph_alloc_readdir_reply_buffer(req, inode);
482 if (err)
483 goto out;
484
485 req->r_direct_mode = USE_AUTH_MDS;
486 req->r_readdir_offset = next_offset;
487 req->r_args.readdir.flags =
488 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
489 if (last_name) {
490 req->r_path2 = last_name;
491 last_name = NULL;
492 }
493
494 req->r_inode = dir;
495 ihold(dir);
496 req->r_dentry = dget(parent);
497
498 inode_lock(dir);
499 err = ceph_mdsc_do_request(fsc->mdsc, NULL, req);
500 inode_unlock(dir);
501
502 if (err < 0)
503 goto out;
504
505 rinfo = &req->r_reply_info;
506 for (i = 0; i < rinfo->dir_nr; i++) {
507 rde = rinfo->dir_entries + i;
508 BUG_ON(!rde->inode.in);
509 if (ceph_snap(inode) ==
510 le64_to_cpu(rde->inode.in->snapid)) {
511 memcpy(name, rde->name, rde->name_len);
512 name[rde->name_len] = '\0';
513 err = 0;
514 goto out;
515 }
516 }
517
518 if (rinfo->dir_end)
519 break;
520
521 BUG_ON(rinfo->dir_nr <= 0);
522 rde = rinfo->dir_entries + (rinfo->dir_nr - 1);
523 next_offset += rinfo->dir_nr;
524 last_name = kstrndup(rde->name, rde->name_len, GFP_KERNEL);
525 if (!last_name) {
526 err = -ENOMEM;
527 goto out;
528 }
529
530 ceph_mdsc_put_request(req);
531 req = NULL;
532 }
533 err = -ENOENT;
534out:
535 if (req)
536 ceph_mdsc_put_request(req);
537 kfree(last_name);
538 doutc(fsc->client, "child dentry %p %p %llx.%llx err=%d\n", child,
539 inode, ceph_vinop(inode), err);
540 return err;
541}
542
543static int ceph_get_name(struct dentry *parent, char *name,
544 struct dentry *child)
545{
546 struct ceph_mds_client *mdsc;
547 struct ceph_mds_request *req;
548 struct inode *dir = d_inode(parent);
549 struct inode *inode = d_inode(child);
550 struct ceph_mds_reply_info_parsed *rinfo;
551 int err;
552
553 if (ceph_snap(inode) != CEPH_NOSNAP)
554 return __get_snap_name(parent, name, child);
555
556 mdsc = ceph_inode_to_fs_client(inode)->mdsc;
557 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME,
558 USE_ANY_MDS);
559 if (IS_ERR(req))
560 return PTR_ERR(req);
561
562 inode_lock(dir);
563 req->r_inode = inode;
564 ihold(inode);
565 req->r_ino2 = ceph_vino(d_inode(parent));
566 req->r_parent = dir;
567 ihold(dir);
568 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
569 req->r_num_caps = 2;
570 err = ceph_mdsc_do_request(mdsc, NULL, req);
571 inode_unlock(dir);
572
573 if (err)
574 goto out;
575
576 rinfo = &req->r_reply_info;
577 if (!IS_ENCRYPTED(dir)) {
578 memcpy(name, rinfo->dname, rinfo->dname_len);
579 name[rinfo->dname_len] = 0;
580 } else {
581 struct fscrypt_str oname = FSTR_INIT(NULL, 0);
582 struct ceph_fname fname = { .dir = dir,
583 .name = rinfo->dname,
584 .ctext = rinfo->altname,
585 .name_len = rinfo->dname_len,
586 .ctext_len = rinfo->altname_len };
587
588 err = ceph_fname_alloc_buffer(dir, &oname);
589 if (err < 0)
590 goto out;
591
592 err = ceph_fname_to_usr(&fname, NULL, &oname, NULL);
593 if (!err) {
594 memcpy(name, oname.name, oname.len);
595 name[oname.len] = 0;
596 }
597 ceph_fname_free_buffer(dir, &oname);
598 }
599out:
600 doutc(mdsc->fsc->client, "child dentry %p %p %llx.%llx err %d %s%s\n",
601 child, inode, ceph_vinop(inode), err, err ? "" : "name ",
602 err ? "" : name);
603 ceph_mdsc_put_request(req);
604 return err;
605}
606
607const struct export_operations ceph_export_ops = {
608 .encode_fh = ceph_encode_fh,
609 .fh_to_dentry = ceph_fh_to_dentry,
610 .fh_to_parent = ceph_fh_to_parent,
611 .get_parent = ceph_get_parent,
612 .get_name = ceph_get_name,
613};