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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 <asm/unaligned.h>
7
8#include "super.h"
9#include "mds_client.h"
10
11/*
12 * Basic fh
13 */
14struct ceph_nfs_fh {
15 u64 ino;
16} __attribute__ ((packed));
17
18/*
19 * Larger fh that includes parent ino.
20 */
21struct ceph_nfs_confh {
22 u64 ino, parent_ino;
23} __attribute__ ((packed));
24
25/*
26 * fh for snapped inode
27 */
28struct ceph_nfs_snapfh {
29 u64 ino;
30 u64 snapid;
31 u64 parent_ino;
32 u32 hash;
33} __attribute__ ((packed));
34
35static int ceph_encode_snapfh(struct inode *inode, u32 *rawfh, int *max_len,
36 struct inode *parent_inode)
37{
38 static const int snap_handle_length =
39 sizeof(struct ceph_nfs_snapfh) >> 2;
40 struct ceph_nfs_snapfh *sfh = (void *)rawfh;
41 u64 snapid = ceph_snap(inode);
42 int ret;
43 bool no_parent = true;
44
45 if (*max_len < snap_handle_length) {
46 *max_len = snap_handle_length;
47 ret = FILEID_INVALID;
48 goto out;
49 }
50
51 ret = -EINVAL;
52 if (snapid != CEPH_SNAPDIR) {
53 struct inode *dir;
54 struct dentry *dentry = d_find_alias(inode);
55 if (!dentry)
56 goto out;
57
58 rcu_read_lock();
59 dir = d_inode_rcu(dentry->d_parent);
60 if (ceph_snap(dir) != CEPH_SNAPDIR) {
61 sfh->parent_ino = ceph_ino(dir);
62 sfh->hash = ceph_dentry_hash(dir, dentry);
63 no_parent = false;
64 }
65 rcu_read_unlock();
66 dput(dentry);
67 }
68
69 if (no_parent) {
70 if (!S_ISDIR(inode->i_mode))
71 goto out;
72 sfh->parent_ino = sfh->ino;
73 sfh->hash = 0;
74 }
75 sfh->ino = ceph_ino(inode);
76 sfh->snapid = snapid;
77
78 *max_len = snap_handle_length;
79 ret = FILEID_BTRFS_WITH_PARENT;
80out:
81 dout("encode_snapfh %llx.%llx ret=%d\n", ceph_vinop(inode), ret);
82 return ret;
83}
84
85static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
86 struct inode *parent_inode)
87{
88 static const int handle_length =
89 sizeof(struct ceph_nfs_fh) >> 2;
90 static const int connected_handle_length =
91 sizeof(struct ceph_nfs_confh) >> 2;
92 int type;
93
94 if (ceph_snap(inode) != CEPH_NOSNAP)
95 return ceph_encode_snapfh(inode, rawfh, max_len, parent_inode);
96
97 if (parent_inode && (*max_len < connected_handle_length)) {
98 *max_len = connected_handle_length;
99 return FILEID_INVALID;
100 } else if (*max_len < handle_length) {
101 *max_len = handle_length;
102 return FILEID_INVALID;
103 }
104
105 if (parent_inode) {
106 struct ceph_nfs_confh *cfh = (void *)rawfh;
107 dout("encode_fh %llx with parent %llx\n",
108 ceph_ino(inode), ceph_ino(parent_inode));
109 cfh->ino = ceph_ino(inode);
110 cfh->parent_ino = ceph_ino(parent_inode);
111 *max_len = connected_handle_length;
112 type = FILEID_INO32_GEN_PARENT;
113 } else {
114 struct ceph_nfs_fh *fh = (void *)rawfh;
115 dout("encode_fh %llx\n", ceph_ino(inode));
116 fh->ino = ceph_ino(inode);
117 *max_len = handle_length;
118 type = FILEID_INO32_GEN;
119 }
120 return type;
121}
122
123static struct inode *__lookup_inode(struct super_block *sb, u64 ino)
124{
125 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
126 struct inode *inode;
127 struct ceph_vino vino;
128 int err;
129
130 vino.ino = ino;
131 vino.snap = CEPH_NOSNAP;
132 inode = ceph_find_inode(sb, vino);
133 if (!inode) {
134 struct ceph_mds_request *req;
135 int mask;
136
137 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
138 USE_ANY_MDS);
139 if (IS_ERR(req))
140 return ERR_CAST(req);
141
142 mask = CEPH_STAT_CAP_INODE;
143 if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
144 mask |= CEPH_CAP_XATTR_SHARED;
145 req->r_args.lookupino.mask = cpu_to_le32(mask);
146
147 req->r_ino1 = vino;
148 req->r_num_caps = 1;
149 err = ceph_mdsc_do_request(mdsc, NULL, req);
150 inode = req->r_target_inode;
151 if (inode)
152 ihold(inode);
153 ceph_mdsc_put_request(req);
154 if (!inode)
155 return err < 0 ? ERR_PTR(err) : ERR_PTR(-ESTALE);
156 }
157 return inode;
158}
159
160struct inode *ceph_lookup_inode(struct super_block *sb, u64 ino)
161{
162 struct inode *inode = __lookup_inode(sb, ino);
163 if (IS_ERR(inode))
164 return inode;
165 if (inode->i_nlink == 0) {
166 iput(inode);
167 return ERR_PTR(-ESTALE);
168 }
169 return inode;
170}
171
172static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
173{
174 struct inode *inode = __lookup_inode(sb, ino);
175 if (IS_ERR(inode))
176 return ERR_CAST(inode);
177 if (inode->i_nlink == 0) {
178 iput(inode);
179 return ERR_PTR(-ESTALE);
180 }
181 return d_obtain_alias(inode);
182}
183
184static struct dentry *__snapfh_to_dentry(struct super_block *sb,
185 struct ceph_nfs_snapfh *sfh,
186 bool want_parent)
187{
188 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
189 struct ceph_mds_request *req;
190 struct inode *inode;
191 struct ceph_vino vino;
192 int mask;
193 int err;
194 bool unlinked = false;
195
196 if (want_parent) {
197 vino.ino = sfh->parent_ino;
198 if (sfh->snapid == CEPH_SNAPDIR)
199 vino.snap = CEPH_NOSNAP;
200 else if (sfh->ino == sfh->parent_ino)
201 vino.snap = CEPH_SNAPDIR;
202 else
203 vino.snap = sfh->snapid;
204 } else {
205 vino.ino = sfh->ino;
206 vino.snap = sfh->snapid;
207 }
208 inode = ceph_find_inode(sb, vino);
209 if (inode)
210 return d_obtain_alias(inode);
211
212 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
213 USE_ANY_MDS);
214 if (IS_ERR(req))
215 return ERR_CAST(req);
216
217 mask = CEPH_STAT_CAP_INODE;
218 if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
219 mask |= CEPH_CAP_XATTR_SHARED;
220 req->r_args.lookupino.mask = cpu_to_le32(mask);
221 if (vino.snap < CEPH_NOSNAP) {
222 req->r_args.lookupino.snapid = cpu_to_le64(vino.snap);
223 if (!want_parent && sfh->ino != sfh->parent_ino) {
224 req->r_args.lookupino.parent =
225 cpu_to_le64(sfh->parent_ino);
226 req->r_args.lookupino.hash =
227 cpu_to_le32(sfh->hash);
228 }
229 }
230
231 req->r_ino1 = vino;
232 req->r_num_caps = 1;
233 err = ceph_mdsc_do_request(mdsc, NULL, req);
234 inode = req->r_target_inode;
235 if (inode) {
236 if (vino.snap == CEPH_SNAPDIR) {
237 if (inode->i_nlink == 0)
238 unlinked = true;
239 inode = ceph_get_snapdir(inode);
240 } else if (ceph_snap(inode) == vino.snap) {
241 ihold(inode);
242 } else {
243 /* mds does not support lookup snapped inode */
244 err = -EOPNOTSUPP;
245 inode = NULL;
246 }
247 }
248 ceph_mdsc_put_request(req);
249
250 if (want_parent) {
251 dout("snapfh_to_parent %llx.%llx\n err=%d\n",
252 vino.ino, vino.snap, err);
253 } else {
254 dout("snapfh_to_dentry %llx.%llx parent %llx hash %x err=%d",
255 vino.ino, vino.snap, sfh->parent_ino, sfh->hash, err);
256 }
257 if (!inode)
258 return ERR_PTR(-ESTALE);
259 /* see comments in ceph_get_parent() */
260 return unlinked ? d_obtain_root(inode) : d_obtain_alias(inode);
261}
262
263/*
264 * convert regular fh to dentry
265 */
266static struct dentry *ceph_fh_to_dentry(struct super_block *sb,
267 struct fid *fid,
268 int fh_len, int fh_type)
269{
270 struct ceph_nfs_fh *fh = (void *)fid->raw;
271
272 if (fh_type == FILEID_BTRFS_WITH_PARENT) {
273 struct ceph_nfs_snapfh *sfh = (void *)fid->raw;
274 return __snapfh_to_dentry(sb, sfh, false);
275 }
276
277 if (fh_type != FILEID_INO32_GEN &&
278 fh_type != FILEID_INO32_GEN_PARENT)
279 return NULL;
280 if (fh_len < sizeof(*fh) / 4)
281 return NULL;
282
283 dout("fh_to_dentry %llx\n", fh->ino);
284 return __fh_to_dentry(sb, fh->ino);
285}
286
287static struct dentry *__get_parent(struct super_block *sb,
288 struct dentry *child, u64 ino)
289{
290 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
291 struct ceph_mds_request *req;
292 struct inode *inode;
293 int mask;
294 int err;
295
296 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT,
297 USE_ANY_MDS);
298 if (IS_ERR(req))
299 return ERR_CAST(req);
300
301 if (child) {
302 req->r_inode = d_inode(child);
303 ihold(d_inode(child));
304 } else {
305 req->r_ino1 = (struct ceph_vino) {
306 .ino = ino,
307 .snap = CEPH_NOSNAP,
308 };
309 }
310
311 mask = CEPH_STAT_CAP_INODE;
312 if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
313 mask |= CEPH_CAP_XATTR_SHARED;
314 req->r_args.getattr.mask = cpu_to_le32(mask);
315
316 req->r_num_caps = 1;
317 err = ceph_mdsc_do_request(mdsc, NULL, req);
318 inode = req->r_target_inode;
319 if (inode)
320 ihold(inode);
321 ceph_mdsc_put_request(req);
322 if (!inode)
323 return ERR_PTR(-ENOENT);
324
325 return d_obtain_alias(inode);
326}
327
328static struct dentry *ceph_get_parent(struct dentry *child)
329{
330 struct inode *inode = d_inode(child);
331 struct dentry *dn;
332
333 if (ceph_snap(inode) != CEPH_NOSNAP) {
334 struct inode* dir;
335 bool unlinked = false;
336 /* do not support non-directory */
337 if (!d_is_dir(child)) {
338 dn = ERR_PTR(-EINVAL);
339 goto out;
340 }
341 dir = __lookup_inode(inode->i_sb, ceph_ino(inode));
342 if (IS_ERR(dir)) {
343 dn = ERR_CAST(dir);
344 goto out;
345 }
346 /* There can be multiple paths to access snapped inode.
347 * For simplicity, treat snapdir of head inode as parent */
348 if (ceph_snap(inode) != CEPH_SNAPDIR) {
349 struct inode *snapdir = ceph_get_snapdir(dir);
350 if (dir->i_nlink == 0)
351 unlinked = true;
352 iput(dir);
353 if (IS_ERR(snapdir)) {
354 dn = ERR_CAST(snapdir);
355 goto out;
356 }
357 dir = snapdir;
358 }
359 /* If directory has already been deleted, futher get_parent
360 * will fail. Do not mark snapdir dentry as disconnected,
361 * this prevent exportfs from doing futher get_parent. */
362 if (unlinked)
363 dn = d_obtain_root(dir);
364 else
365 dn = d_obtain_alias(dir);
366 } else {
367 dn = __get_parent(child->d_sb, child, 0);
368 }
369out:
370 dout("get_parent %p ino %llx.%llx err=%ld\n",
371 child, ceph_vinop(inode), (long)PTR_ERR_OR_ZERO(dn));
372 return dn;
373}
374
375/*
376 * convert regular fh to parent
377 */
378static struct dentry *ceph_fh_to_parent(struct super_block *sb,
379 struct fid *fid,
380 int fh_len, int fh_type)
381{
382 struct ceph_nfs_confh *cfh = (void *)fid->raw;
383 struct dentry *dentry;
384
385 if (fh_type == FILEID_BTRFS_WITH_PARENT) {
386 struct ceph_nfs_snapfh *sfh = (void *)fid->raw;
387 return __snapfh_to_dentry(sb, sfh, true);
388 }
389
390 if (fh_type != FILEID_INO32_GEN_PARENT)
391 return NULL;
392 if (fh_len < sizeof(*cfh) / 4)
393 return NULL;
394
395 dout("fh_to_parent %llx\n", cfh->parent_ino);
396 dentry = __get_parent(sb, NULL, cfh->ino);
397 if (unlikely(dentry == ERR_PTR(-ENOENT)))
398 dentry = __fh_to_dentry(sb, cfh->parent_ino);
399 return dentry;
400}
401
402static int __get_snap_name(struct dentry *parent, char *name,
403 struct dentry *child)
404{
405 struct inode *inode = d_inode(child);
406 struct inode *dir = d_inode(parent);
407 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
408 struct ceph_mds_request *req = NULL;
409 char *last_name = NULL;
410 unsigned next_offset = 2;
411 int err = -EINVAL;
412
413 if (ceph_ino(inode) != ceph_ino(dir))
414 goto out;
415 if (ceph_snap(inode) == CEPH_SNAPDIR) {
416 if (ceph_snap(dir) == CEPH_NOSNAP) {
417 strcpy(name, fsc->mount_options->snapdir_name);
418 err = 0;
419 }
420 goto out;
421 }
422 if (ceph_snap(dir) != CEPH_SNAPDIR)
423 goto out;
424
425 while (1) {
426 struct ceph_mds_reply_info_parsed *rinfo;
427 struct ceph_mds_reply_dir_entry *rde;
428 int i;
429
430 req = ceph_mdsc_create_request(fsc->mdsc, CEPH_MDS_OP_LSSNAP,
431 USE_AUTH_MDS);
432 if (IS_ERR(req)) {
433 err = PTR_ERR(req);
434 req = NULL;
435 goto out;
436 }
437 err = ceph_alloc_readdir_reply_buffer(req, inode);
438 if (err)
439 goto out;
440
441 req->r_direct_mode = USE_AUTH_MDS;
442 req->r_readdir_offset = next_offset;
443 req->r_args.readdir.flags =
444 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
445 if (last_name) {
446 req->r_path2 = last_name;
447 last_name = NULL;
448 }
449
450 req->r_inode = dir;
451 ihold(dir);
452 req->r_dentry = dget(parent);
453
454 inode_lock(dir);
455 err = ceph_mdsc_do_request(fsc->mdsc, NULL, req);
456 inode_unlock(dir);
457
458 if (err < 0)
459 goto out;
460
461 rinfo = &req->r_reply_info;
462 for (i = 0; i < rinfo->dir_nr; i++) {
463 rde = rinfo->dir_entries + i;
464 BUG_ON(!rde->inode.in);
465 if (ceph_snap(inode) ==
466 le64_to_cpu(rde->inode.in->snapid)) {
467 memcpy(name, rde->name, rde->name_len);
468 name[rde->name_len] = '\0';
469 err = 0;
470 goto out;
471 }
472 }
473
474 if (rinfo->dir_end)
475 break;
476
477 BUG_ON(rinfo->dir_nr <= 0);
478 rde = rinfo->dir_entries + (rinfo->dir_nr - 1);
479 next_offset += rinfo->dir_nr;
480 last_name = kstrndup(rde->name, rde->name_len, GFP_KERNEL);
481 if (!last_name) {
482 err = -ENOMEM;
483 goto out;
484 }
485
486 ceph_mdsc_put_request(req);
487 req = NULL;
488 }
489 err = -ENOENT;
490out:
491 if (req)
492 ceph_mdsc_put_request(req);
493 kfree(last_name);
494 dout("get_snap_name %p ino %llx.%llx err=%d\n",
495 child, ceph_vinop(inode), err);
496 return err;
497}
498
499static int ceph_get_name(struct dentry *parent, char *name,
500 struct dentry *child)
501{
502 struct ceph_mds_client *mdsc;
503 struct ceph_mds_request *req;
504 struct inode *inode = d_inode(child);
505 int err;
506
507 if (ceph_snap(inode) != CEPH_NOSNAP)
508 return __get_snap_name(parent, name, child);
509
510 mdsc = ceph_inode_to_client(inode)->mdsc;
511 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME,
512 USE_ANY_MDS);
513 if (IS_ERR(req))
514 return PTR_ERR(req);
515
516 inode_lock(d_inode(parent));
517
518 req->r_inode = inode;
519 ihold(inode);
520 req->r_ino2 = ceph_vino(d_inode(parent));
521 req->r_parent = d_inode(parent);
522 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
523 req->r_num_caps = 2;
524 err = ceph_mdsc_do_request(mdsc, NULL, req);
525
526 inode_unlock(d_inode(parent));
527
528 if (!err) {
529 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
530 memcpy(name, rinfo->dname, rinfo->dname_len);
531 name[rinfo->dname_len] = 0;
532 dout("get_name %p ino %llx.%llx name %s\n",
533 child, ceph_vinop(inode), name);
534 } else {
535 dout("get_name %p ino %llx.%llx err %d\n",
536 child, ceph_vinop(inode), err);
537 }
538
539 ceph_mdsc_put_request(req);
540 return err;
541}
542
543const struct export_operations ceph_export_ops = {
544 .encode_fh = ceph_encode_fh,
545 .fh_to_dentry = ceph_fh_to_dentry,
546 .fh_to_parent = ceph_fh_to_parent,
547 .get_parent = ceph_get_parent,
548 .get_name = ceph_get_name,
549};
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 * NFS export support
12 *
13 * NFS re-export of a ceph mount is, at present, only semireliable.
14 * The basic issue is that the Ceph architectures doesn't lend itself
15 * well to generating filehandles that will remain valid forever.
16 *
17 * So, we do our best. If you're lucky, your inode will be in the
18 * client's cache. If it's not, and you have a connectable fh, then
19 * the MDS server may be able to find it for you. Otherwise, you get
20 * ESTALE.
21 *
22 * There are ways to this more reliable, but in the non-connectable fh
23 * case, we won't every work perfectly, and in the connectable case,
24 * some changes are needed on the MDS side to work better.
25 */
26
27/*
28 * Basic fh
29 */
30struct ceph_nfs_fh {
31 u64 ino;
32} __attribute__ ((packed));
33
34/*
35 * Larger 'connectable' fh that includes parent ino and name hash.
36 * Use this whenever possible, as it works more reliably.
37 */
38struct ceph_nfs_confh {
39 u64 ino, parent_ino;
40 u32 parent_name_hash;
41} __attribute__ ((packed));
42
43static int ceph_encode_fh(struct dentry *dentry, u32 *rawfh, int *max_len,
44 int connectable)
45{
46 int type;
47 struct ceph_nfs_fh *fh = (void *)rawfh;
48 struct ceph_nfs_confh *cfh = (void *)rawfh;
49 struct dentry *parent;
50 struct inode *inode = dentry->d_inode;
51 int connected_handle_length = sizeof(*cfh)/4;
52 int handle_length = sizeof(*fh)/4;
53
54 /* don't re-export snaps */
55 if (ceph_snap(inode) != CEPH_NOSNAP)
56 return -EINVAL;
57
58 spin_lock(&dentry->d_lock);
59 parent = dget(dentry->d_parent);
60 spin_unlock(&dentry->d_lock);
61
62 if (*max_len >= connected_handle_length) {
63 dout("encode_fh %p connectable\n", dentry);
64 cfh->ino = ceph_ino(dentry->d_inode);
65 cfh->parent_ino = ceph_ino(parent->d_inode);
66 cfh->parent_name_hash = ceph_dentry_hash(parent->d_inode,
67 dentry);
68 *max_len = connected_handle_length;
69 type = 2;
70 } else if (*max_len >= handle_length) {
71 if (connectable) {
72 *max_len = connected_handle_length;
73 type = 255;
74 } else {
75 dout("encode_fh %p\n", dentry);
76 fh->ino = ceph_ino(dentry->d_inode);
77 *max_len = handle_length;
78 type = 1;
79 }
80 } else {
81 *max_len = handle_length;
82 type = 255;
83 }
84 dput(parent);
85 return type;
86}
87
88/*
89 * convert regular fh to dentry
90 *
91 * FIXME: we should try harder by querying the mds for the ino.
92 */
93static struct dentry *__fh_to_dentry(struct super_block *sb,
94 struct ceph_nfs_fh *fh)
95{
96 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
97 struct inode *inode;
98 struct dentry *dentry;
99 struct ceph_vino vino;
100 int err;
101
102 dout("__fh_to_dentry %llx\n", fh->ino);
103 vino.ino = fh->ino;
104 vino.snap = CEPH_NOSNAP;
105 inode = ceph_find_inode(sb, vino);
106 if (!inode) {
107 struct ceph_mds_request *req;
108
109 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
110 USE_ANY_MDS);
111 if (IS_ERR(req))
112 return ERR_CAST(req);
113
114 req->r_ino1 = vino;
115 req->r_num_caps = 1;
116 err = ceph_mdsc_do_request(mdsc, NULL, req);
117 inode = req->r_target_inode;
118 if (inode)
119 ihold(inode);
120 ceph_mdsc_put_request(req);
121 if (!inode)
122 return ERR_PTR(-ESTALE);
123 }
124
125 dentry = d_obtain_alias(inode);
126 if (IS_ERR(dentry)) {
127 pr_err("fh_to_dentry %llx -- inode %p but ENOMEM\n",
128 fh->ino, inode);
129 iput(inode);
130 return dentry;
131 }
132 err = ceph_init_dentry(dentry);
133 if (err < 0) {
134 iput(inode);
135 return ERR_PTR(err);
136 }
137 dout("__fh_to_dentry %llx %p dentry %p\n", fh->ino, inode, dentry);
138 return dentry;
139}
140
141/*
142 * convert connectable fh to dentry
143 */
144static struct dentry *__cfh_to_dentry(struct super_block *sb,
145 struct ceph_nfs_confh *cfh)
146{
147 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
148 struct inode *inode;
149 struct dentry *dentry;
150 struct ceph_vino vino;
151 int err;
152
153 dout("__cfh_to_dentry %llx (%llx/%x)\n",
154 cfh->ino, cfh->parent_ino, cfh->parent_name_hash);
155
156 vino.ino = cfh->ino;
157 vino.snap = CEPH_NOSNAP;
158 inode = ceph_find_inode(sb, vino);
159 if (!inode) {
160 struct ceph_mds_request *req;
161
162 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPHASH,
163 USE_ANY_MDS);
164 if (IS_ERR(req))
165 return ERR_CAST(req);
166
167 req->r_ino1 = vino;
168 req->r_ino2.ino = cfh->parent_ino;
169 req->r_ino2.snap = CEPH_NOSNAP;
170 req->r_path2 = kmalloc(16, GFP_NOFS);
171 snprintf(req->r_path2, 16, "%d", cfh->parent_name_hash);
172 req->r_num_caps = 1;
173 err = ceph_mdsc_do_request(mdsc, NULL, req);
174 inode = req->r_target_inode;
175 if (inode)
176 ihold(inode);
177 ceph_mdsc_put_request(req);
178 if (!inode)
179 return ERR_PTR(err ? err : -ESTALE);
180 }
181
182 dentry = d_obtain_alias(inode);
183 if (IS_ERR(dentry)) {
184 pr_err("cfh_to_dentry %llx -- inode %p but ENOMEM\n",
185 cfh->ino, inode);
186 iput(inode);
187 return dentry;
188 }
189 err = ceph_init_dentry(dentry);
190 if (err < 0) {
191 iput(inode);
192 return ERR_PTR(err);
193 }
194 dout("__cfh_to_dentry %llx %p dentry %p\n", cfh->ino, inode, dentry);
195 return dentry;
196}
197
198static struct dentry *ceph_fh_to_dentry(struct super_block *sb, struct fid *fid,
199 int fh_len, int fh_type)
200{
201 if (fh_type == 1)
202 return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw);
203 else
204 return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw);
205}
206
207/*
208 * get parent, if possible.
209 *
210 * FIXME: we could do better by querying the mds to discover the
211 * parent.
212 */
213static struct dentry *ceph_fh_to_parent(struct super_block *sb,
214 struct fid *fid,
215 int fh_len, int fh_type)
216{
217 struct ceph_nfs_confh *cfh = (void *)fid->raw;
218 struct ceph_vino vino;
219 struct inode *inode;
220 struct dentry *dentry;
221 int err;
222
223 if (fh_type == 1)
224 return ERR_PTR(-ESTALE);
225
226 pr_debug("fh_to_parent %llx/%d\n", cfh->parent_ino,
227 cfh->parent_name_hash);
228
229 vino.ino = cfh->ino;
230 vino.snap = CEPH_NOSNAP;
231 inode = ceph_find_inode(sb, vino);
232 if (!inode)
233 return ERR_PTR(-ESTALE);
234
235 dentry = d_obtain_alias(inode);
236 if (IS_ERR(dentry)) {
237 pr_err("fh_to_parent %llx -- inode %p but ENOMEM\n",
238 cfh->ino, inode);
239 iput(inode);
240 return dentry;
241 }
242 err = ceph_init_dentry(dentry);
243 if (err < 0) {
244 iput(inode);
245 return ERR_PTR(err);
246 }
247 dout("fh_to_parent %llx %p dentry %p\n", cfh->ino, inode, dentry);
248 return dentry;
249}
250
251const struct export_operations ceph_export_ops = {
252 .encode_fh = ceph_encode_fh,
253 .fh_to_dentry = ceph_fh_to_dentry,
254 .fh_to_parent = ceph_fh_to_parent,
255};