1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/ceph/ceph_debug.h>
3
4 #include <linux/spinlock.h>
5 #include <linux/namei.h>
6 #include <linux/slab.h>
7 #include <linux/sched.h>
8 #include <linux/xattr.h>
9
10 #include "super.h"
11 #include "mds_client.h"
12 #include "crypto.h"
13
14 /*
15 * Directory operations: readdir, lookup, create, link, unlink,
16 * rename, etc.
17 */
18
19 /*
20 * Ceph MDS operations are specified in terms of a base ino and
21 * relative path. Thus, the client can specify an operation on a
22 * specific inode (e.g., a getattr due to fstat(2)), or as a path
23 * relative to, say, the root directory.
24 *
25 * Normally, we limit ourselves to strict inode ops (no path component)
26 * or dentry operations (a single path component relative to an ino). The
27 * exception to this is open_root_dentry(), which will open the mount
28 * point by name.
29 */
30
31 const struct dentry_operations ceph_dentry_ops;
32
33 static bool __dentry_lease_is_valid(struct ceph_dentry_info *di);
34 static int __dir_lease_try_check(const struct dentry *dentry);
35
36 /*
37 * Initialize ceph dentry state.
38 */
39 static int ceph_d_init(struct dentry *dentry)
40 {
41 struct ceph_dentry_info *di;
42 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);
43
44 di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
45 if (!di)
46 return -ENOMEM; /* oh well */
47
48 di->dentry = dentry;
49 di->lease_session = NULL;
50 di->time = jiffies;
51 dentry->d_fsdata = di;
52 INIT_LIST_HEAD(&di->lease_list);
53
54 atomic64_inc(&mdsc->metric.total_dentries);
55
56 return 0;
57 }
58
59 /*
60 * for f_pos for readdir:
61 * - hash order:
62 * (0xff << 52) | ((24 bits hash) << 28) |
63 * (the nth entry has hash collision);
64 * - frag+name order;
65 * ((frag value) << 28) | (the nth entry in frag);
66 */
67 #define OFFSET_BITS 28
68 #define OFFSET_MASK ((1 << OFFSET_BITS) - 1)
69 #define HASH_ORDER (0xffull << (OFFSET_BITS + 24))
70 loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
71 {
72 loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
73 if (hash_order)
74 fpos |= HASH_ORDER;
75 return fpos;
76 }
77
78 static bool is_hash_order(loff_t p)
79 {
80 return (p & HASH_ORDER) == HASH_ORDER;
81 }
82
83 static unsigned fpos_frag(loff_t p)
84 {
85 return p >> OFFSET_BITS;
86 }
87
88 static unsigned fpos_hash(loff_t p)
89 {
90 return ceph_frag_value(fpos_frag(p));
91 }
92
93 static unsigned fpos_off(loff_t p)
94 {
95 return p & OFFSET_MASK;
96 }
97
98 static int fpos_cmp(loff_t l, loff_t r)
99 {
100 int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
101 if (v)
102 return v;
103 return (int)(fpos_off(l) - fpos_off(r));
104 }
105
106 /*
107 * make note of the last dentry we read, so we can
108 * continue at the same lexicographical point,
109 * regardless of what dir changes take place on the
110 * server.
111 */
112 static int note_last_dentry(struct ceph_fs_client *fsc,
113 struct ceph_dir_file_info *dfi,
114 const char *name,
115 int len, unsigned next_offset)
116 {
117 char *buf = kmalloc(len+1, GFP_KERNEL);
118 if (!buf)
119 return -ENOMEM;
120 kfree(dfi->last_name);
121 dfi->last_name = buf;
122 memcpy(dfi->last_name, name, len);
123 dfi->last_name[len] = 0;
124 dfi->next_offset = next_offset;
125 doutc(fsc->client, "'%s'\n", dfi->last_name);
126 return 0;
127 }
128
129
130 static struct dentry *
131 __dcache_find_get_entry(struct dentry *parent, u64 idx,
132 struct ceph_readdir_cache_control *cache_ctl)
133 {
134 struct inode *dir = d_inode(parent);
135 struct ceph_client *cl = ceph_inode_to_client(dir);
136 struct dentry *dentry;
137 unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
138 loff_t ptr_pos = idx * sizeof(struct dentry *);
139 pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
140
141 if (ptr_pos >= i_size_read(dir))
142 return NULL;
143
144 if (!cache_ctl->page || ptr_pgoff != cache_ctl->page->index) {
145 ceph_readdir_cache_release(cache_ctl);
146 cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
147 if (!cache_ctl->page) {
148 doutc(cl, " page %lu not found\n", ptr_pgoff);
149 return ERR_PTR(-EAGAIN);
150 }
151 /* reading/filling the cache are serialized by
152 i_rwsem, no need to use page lock */
153 unlock_page(cache_ctl->page);
154 cache_ctl->dentries = kmap(cache_ctl->page);
155 }
156
157 cache_ctl->index = idx & idx_mask;
158
159 rcu_read_lock();
160 spin_lock(&parent->d_lock);
161 /* check i_size again here, because empty directory can be
162 * marked as complete while not holding the i_rwsem. */
163 if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))
164 dentry = cache_ctl->dentries[cache_ctl->index];
165 else
166 dentry = NULL;
167 spin_unlock(&parent->d_lock);
168 if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
169 dentry = NULL;
170 rcu_read_unlock();
171 return dentry ? : ERR_PTR(-EAGAIN);
172 }
173
174 /*
175 * When possible, we try to satisfy a readdir by peeking at the
176 * dcache. We make this work by carefully ordering dentries on
177 * d_children when we initially get results back from the MDS, and
178 * falling back to a "normal" sync readdir if any dentries in the dir
179 * are dropped.
180 *
181 * Complete dir indicates that we have all dentries in the dir. It is
182 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
183 * the MDS if/when the directory is modified).
184 */
185 static int __dcache_readdir(struct file *file, struct dir_context *ctx,
186 int shared_gen)
187 {
188 struct ceph_dir_file_info *dfi = file->private_data;
189 struct dentry *parent = file->f_path.dentry;
190 struct inode *dir = d_inode(parent);
191 struct ceph_fs_client *fsc = ceph_inode_to_fs_client(dir);
192 struct ceph_client *cl = ceph_inode_to_client(dir);
193 struct dentry *dentry, *last = NULL;
194 struct ceph_dentry_info *di;
195 struct ceph_readdir_cache_control cache_ctl = {};
196 u64 idx = 0;
197 int err = 0;
198
199 doutc(cl, "%p %llx.%llx v%u at %llx\n", dir, ceph_vinop(dir),
200 (unsigned)shared_gen, ctx->pos);
201
202 /* search start position */
203 if (ctx->pos > 2) {
204 u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
205 while (count > 0) {
206 u64 step = count >> 1;
207 dentry = __dcache_find_get_entry(parent, idx + step,
208 &cache_ctl);
209 if (!dentry) {
210 /* use linar search */
211 idx = 0;
212 break;
213 }
214 if (IS_ERR(dentry)) {
215 err = PTR_ERR(dentry);
216 goto out;
217 }
218 di = ceph_dentry(dentry);
219 spin_lock(&dentry->d_lock);
220 if (fpos_cmp(di->offset, ctx->pos) < 0) {
221 idx += step + 1;
222 count -= step + 1;
223 } else {
224 count = step;
225 }
226 spin_unlock(&dentry->d_lock);
227 dput(dentry);
228 }
229
230 doutc(cl, "%p %llx.%llx cache idx %llu\n", dir,
231 ceph_vinop(dir), idx);
232 }
233
234
235 for (;;) {
236 bool emit_dentry = false;
237 dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
238 if (!dentry) {
239 dfi->file_info.flags |= CEPH_F_ATEND;
240 err = 0;
241 break;
242 }
243 if (IS_ERR(dentry)) {
244 err = PTR_ERR(dentry);
245 goto out;
246 }
247
248 spin_lock(&dentry->d_lock);
249 di = ceph_dentry(dentry);
250 if (d_unhashed(dentry) ||
251 d_really_is_negative(dentry) ||
252 di->lease_shared_gen != shared_gen ||
253 ((dentry->d_flags & DCACHE_NOKEY_NAME) &&
254 fscrypt_has_encryption_key(dir))) {
255 spin_unlock(&dentry->d_lock);
256 dput(dentry);
257 err = -EAGAIN;
258 goto out;
259 }
260 if (fpos_cmp(ctx->pos, di->offset) <= 0) {
261 __ceph_dentry_dir_lease_touch(di);
262 emit_dentry = true;
263 }
264 spin_unlock(&dentry->d_lock);
265
266 if (emit_dentry) {
267 doutc(cl, " %llx dentry %p %pd %p\n", di->offset,
268 dentry, dentry, d_inode(dentry));
269 ctx->pos = di->offset;
270 if (!dir_emit(ctx, dentry->d_name.name,
271 dentry->d_name.len, ceph_present_inode(d_inode(dentry)),
272 d_inode(dentry)->i_mode >> 12)) {
273 dput(dentry);
274 err = 0;
275 break;
276 }
277 ctx->pos++;
278
279 if (last)
280 dput(last);
281 last = dentry;
282 } else {
283 dput(dentry);
284 }
285 }
286 out:
287 ceph_readdir_cache_release(&cache_ctl);
288 if (last) {
289 int ret;
290 di = ceph_dentry(last);
291 ret = note_last_dentry(fsc, dfi, last->d_name.name,
292 last->d_name.len,
293 fpos_off(di->offset) + 1);
294 if (ret < 0)
295 err = ret;
296 dput(last);
297 /* last_name no longer match cache index */
298 if (dfi->readdir_cache_idx >= 0) {
299 dfi->readdir_cache_idx = -1;
300 dfi->dir_release_count = 0;
301 }
302 }
303 return err;
304 }
305
306 static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)
307 {
308 if (!dfi->last_readdir)
309 return true;
310 if (is_hash_order(pos))
311 return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));
312 else
313 return dfi->frag != fpos_frag(pos);
314 }
315
316 static int ceph_readdir(struct file *file, struct dir_context *ctx)
317 {
318 struct ceph_dir_file_info *dfi = file->private_data;
319 struct inode *inode = file_inode(file);
320 struct ceph_inode_info *ci = ceph_inode(inode);
321 struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
322 struct ceph_mds_client *mdsc = fsc->mdsc;
323 struct ceph_client *cl = fsc->client;
324 int i;
325 int err;
326 unsigned frag = -1;
327 struct ceph_mds_reply_info_parsed *rinfo;
328
329 doutc(cl, "%p %llx.%llx file %p pos %llx\n", inode,
330 ceph_vinop(inode), file, ctx->pos);
331 if (dfi->file_info.flags & CEPH_F_ATEND)
332 return 0;
333
334 /* always start with . and .. */
335 if (ctx->pos == 0) {
336 doutc(cl, "%p %llx.%llx off 0 -> '.'\n", inode,
337 ceph_vinop(inode));
338 if (!dir_emit(ctx, ".", 1, ceph_present_inode(inode),
339 inode->i_mode >> 12))
340 return 0;
341 ctx->pos = 1;
342 }
343 if (ctx->pos == 1) {
344 u64 ino;
345 struct dentry *dentry = file->f_path.dentry;
346
347 spin_lock(&dentry->d_lock);
348 ino = ceph_present_inode(dentry->d_parent->d_inode);
349 spin_unlock(&dentry->d_lock);
350
351 doutc(cl, "%p %llx.%llx off 1 -> '..'\n", inode,
352 ceph_vinop(inode));
353 if (!dir_emit(ctx, "..", 2, ino, inode->i_mode >> 12))
354 return 0;
355 ctx->pos = 2;
356 }
357
358 err = ceph_fscrypt_prepare_readdir(inode);
359 if (err < 0)
360 return err;
361
362 spin_lock(&ci->i_ceph_lock);
363 /* request Fx cap. if have Fx, we don't need to release Fs cap
364 * for later create/unlink. */
365 __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_WR);
366 /* can we use the dcache? */
367 if (ceph_test_mount_opt(fsc, DCACHE) &&
368 !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
369 ceph_snap(inode) != CEPH_SNAPDIR &&
370 __ceph_dir_is_complete_ordered(ci) &&
371 __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
372 int shared_gen = atomic_read(&ci->i_shared_gen);
373
374 spin_unlock(&ci->i_ceph_lock);
375 err = __dcache_readdir(file, ctx, shared_gen);
376 if (err != -EAGAIN)
377 return err;
378 } else {
379 spin_unlock(&ci->i_ceph_lock);
380 }
381
382 /* proceed with a normal readdir */
383 more:
384 /* do we have the correct frag content buffered? */
385 if (need_send_readdir(dfi, ctx->pos)) {
386 struct ceph_mds_request *req;
387 int op = ceph_snap(inode) == CEPH_SNAPDIR ?
388 CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
389
390 /* discard old result, if any */
391 if (dfi->last_readdir) {
392 ceph_mdsc_put_request(dfi->last_readdir);
393 dfi->last_readdir = NULL;
394 }
395
396 if (is_hash_order(ctx->pos)) {
397 /* fragtree isn't always accurate. choose frag
398 * based on previous reply when possible. */
399 if (frag == (unsigned)-1)
400 frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
401 NULL, NULL);
402 } else {
403 frag = fpos_frag(ctx->pos);
404 }
405
406 doutc(cl, "fetching %p %llx.%llx frag %x offset '%s'\n",
407 inode, ceph_vinop(inode), frag, dfi->last_name);
408 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
409 if (IS_ERR(req))
410 return PTR_ERR(req);
411
412 err = ceph_alloc_readdir_reply_buffer(req, inode);
413 if (err) {
414 ceph_mdsc_put_request(req);
415 return err;
416 }
417 /* hints to request -> mds selection code */
418 req->r_direct_mode = USE_AUTH_MDS;
419 if (op == CEPH_MDS_OP_READDIR) {
420 req->r_direct_hash = ceph_frag_value(frag);
421 __set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
422 req->r_inode_drop = CEPH_CAP_FILE_EXCL;
423 }
424 if (dfi->last_name) {
425 struct qstr d_name = { .name = dfi->last_name,
426 .len = strlen(dfi->last_name) };
427
428 req->r_path2 = kzalloc(NAME_MAX + 1, GFP_KERNEL);
429 if (!req->r_path2) {
430 ceph_mdsc_put_request(req);
431 return -ENOMEM;
432 }
433
434 err = ceph_encode_encrypted_dname(inode, &d_name,
435 req->r_path2);
436 if (err < 0) {
437 ceph_mdsc_put_request(req);
438 return err;
439 }
440 } else if (is_hash_order(ctx->pos)) {
441 req->r_args.readdir.offset_hash =
442 cpu_to_le32(fpos_hash(ctx->pos));
443 }
444
445 req->r_dir_release_cnt = dfi->dir_release_count;
446 req->r_dir_ordered_cnt = dfi->dir_ordered_count;
447 req->r_readdir_cache_idx = dfi->readdir_cache_idx;
448 req->r_readdir_offset = dfi->next_offset;
449 req->r_args.readdir.frag = cpu_to_le32(frag);
450 req->r_args.readdir.flags =
451 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
452
453 req->r_inode = inode;
454 ihold(inode);
455 req->r_dentry = dget(file->f_path.dentry);
456 err = ceph_mdsc_do_request(mdsc, NULL, req);
457 if (err < 0) {
458 ceph_mdsc_put_request(req);
459 return err;
460 }
461 doutc(cl, "%p %llx.%llx got and parsed readdir result=%d"
462 "on frag %x, end=%d, complete=%d, hash_order=%d\n",
463 inode, ceph_vinop(inode), err, frag,
464 (int)req->r_reply_info.dir_end,
465 (int)req->r_reply_info.dir_complete,
466 (int)req->r_reply_info.hash_order);
467
468 rinfo = &req->r_reply_info;
469 if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
470 frag = le32_to_cpu(rinfo->dir_dir->frag);
471 if (!rinfo->hash_order) {
472 dfi->next_offset = req->r_readdir_offset;
473 /* adjust ctx->pos to beginning of frag */
474 ctx->pos = ceph_make_fpos(frag,
475 dfi->next_offset,
476 false);
477 }
478 }
479
480 dfi->frag = frag;
481 dfi->last_readdir = req;
482
483 if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
484 dfi->readdir_cache_idx = req->r_readdir_cache_idx;
485 if (dfi->readdir_cache_idx < 0) {
486 /* preclude from marking dir ordered */
487 dfi->dir_ordered_count = 0;
488 } else if (ceph_frag_is_leftmost(frag) &&
489 dfi->next_offset == 2) {
490 /* note dir version at start of readdir so
491 * we can tell if any dentries get dropped */
492 dfi->dir_release_count = req->r_dir_release_cnt;
493 dfi->dir_ordered_count = req->r_dir_ordered_cnt;
494 }
495 } else {
496 doutc(cl, "%p %llx.%llx !did_prepopulate\n", inode,
497 ceph_vinop(inode));
498 /* disable readdir cache */
499 dfi->readdir_cache_idx = -1;
500 /* preclude from marking dir complete */
501 dfi->dir_release_count = 0;
502 }
503
504 /* note next offset and last dentry name */
505 if (rinfo->dir_nr > 0) {
506 struct ceph_mds_reply_dir_entry *rde =
507 rinfo->dir_entries + (rinfo->dir_nr-1);
508 unsigned next_offset = req->r_reply_info.dir_end ?
509 2 : (fpos_off(rde->offset) + 1);
510 err = note_last_dentry(fsc, dfi, rde->name,
511 rde->name_len, next_offset);
512 if (err) {
513 ceph_mdsc_put_request(dfi->last_readdir);
514 dfi->last_readdir = NULL;
515 return err;
516 }
517 } else if (req->r_reply_info.dir_end) {
518 dfi->next_offset = 2;
519 /* keep last name */
520 }
521 }
522
523 rinfo = &dfi->last_readdir->r_reply_info;
524 doutc(cl, "%p %llx.%llx frag %x num %d pos %llx chunk first %llx\n",
525 inode, ceph_vinop(inode), dfi->frag, rinfo->dir_nr, ctx->pos,
526 rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
527
528 i = 0;
529 /* search start position */
530 if (rinfo->dir_nr > 0) {
531 int step, nr = rinfo->dir_nr;
532 while (nr > 0) {
533 step = nr >> 1;
534 if (rinfo->dir_entries[i + step].offset < ctx->pos) {
535 i += step + 1;
536 nr -= step + 1;
537 } else {
538 nr = step;
539 }
540 }
541 }
542 for (; i < rinfo->dir_nr; i++) {
543 struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
544
545 if (rde->offset < ctx->pos) {
546 pr_warn_client(cl,
547 "%p %llx.%llx rde->offset 0x%llx ctx->pos 0x%llx\n",
548 inode, ceph_vinop(inode), rde->offset, ctx->pos);
549 return -EIO;
550 }
551
552 if (WARN_ON_ONCE(!rde->inode.in))
553 return -EIO;
554
555 ctx->pos = rde->offset;
556 doutc(cl, "%p %llx.%llx (%d/%d) -> %llx '%.*s' %p\n", inode,
557 ceph_vinop(inode), i, rinfo->dir_nr, ctx->pos,
558 rde->name_len, rde->name, &rde->inode.in);
559
560 if (!dir_emit(ctx, rde->name, rde->name_len,
561 ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
562 le32_to_cpu(rde->inode.in->mode) >> 12)) {
563 /*
564 * NOTE: Here no need to put the 'dfi->last_readdir',
565 * because when dir_emit stops us it's most likely
566 * doesn't have enough memory, etc. So for next readdir
567 * it will continue.
568 */
569 doutc(cl, "filldir stopping us...\n");
570 return 0;
571 }
572
573 /* Reset the lengths to their original allocated vals */
574 ctx->pos++;
575 }
576
577 ceph_mdsc_put_request(dfi->last_readdir);
578 dfi->last_readdir = NULL;
579
580 if (dfi->next_offset > 2) {
581 frag = dfi->frag;
582 goto more;
583 }
584
585 /* more frags? */
586 if (!ceph_frag_is_rightmost(dfi->frag)) {
587 frag = ceph_frag_next(dfi->frag);
588 if (is_hash_order(ctx->pos)) {
589 loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
590 dfi->next_offset, true);
591 if (new_pos > ctx->pos)
592 ctx->pos = new_pos;
593 /* keep last_name */
594 } else {
595 ctx->pos = ceph_make_fpos(frag, dfi->next_offset,
596 false);
597 kfree(dfi->last_name);
598 dfi->last_name = NULL;
599 }
600 doutc(cl, "%p %llx.%llx next frag is %x\n", inode,
601 ceph_vinop(inode), frag);
602 goto more;
603 }
604 dfi->file_info.flags |= CEPH_F_ATEND;
605
606 /*
607 * if dir_release_count still matches the dir, no dentries
608 * were released during the whole readdir, and we should have
609 * the complete dir contents in our cache.
610 */
611 if (atomic64_read(&ci->i_release_count) ==
612 dfi->dir_release_count) {
613 spin_lock(&ci->i_ceph_lock);
614 if (dfi->dir_ordered_count ==
615 atomic64_read(&ci->i_ordered_count)) {
616 doutc(cl, " marking %p %llx.%llx complete and ordered\n",
617 inode, ceph_vinop(inode));
618 /* use i_size to track number of entries in
619 * readdir cache */
620 BUG_ON(dfi->readdir_cache_idx < 0);
621 i_size_write(inode, dfi->readdir_cache_idx *
622 sizeof(struct dentry*));
623 } else {
624 doutc(cl, " marking %llx.%llx complete\n",
625 ceph_vinop(inode));
626 }
627 __ceph_dir_set_complete(ci, dfi->dir_release_count,
628 dfi->dir_ordered_count);
629 spin_unlock(&ci->i_ceph_lock);
630 }
631 doutc(cl, "%p %llx.%llx file %p done.\n", inode, ceph_vinop(inode),
632 file);
633 return 0;
634 }
635
636 static void reset_readdir(struct ceph_dir_file_info *dfi)
637 {
638 if (dfi->last_readdir) {
639 ceph_mdsc_put_request(dfi->last_readdir);
640 dfi->last_readdir = NULL;
641 }
642 kfree(dfi->last_name);
643 dfi->last_name = NULL;
644 dfi->dir_release_count = 0;
645 dfi->readdir_cache_idx = -1;
646 dfi->next_offset = 2; /* compensate for . and .. */
647 dfi->file_info.flags &= ~CEPH_F_ATEND;
648 }
649
650 /*
651 * discard buffered readdir content on seekdir(0), or seek to new frag,
652 * or seek prior to current chunk
653 */
654 static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)
655 {
656 struct ceph_mds_reply_info_parsed *rinfo;
657 loff_t chunk_offset;
658 if (new_pos == 0)
659 return true;
660 if (is_hash_order(new_pos)) {
661 /* no need to reset last_name for a forward seek when
662 * dentries are sotred in hash order */
663 } else if (dfi->frag != fpos_frag(new_pos)) {
664 return true;
665 }
666 rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;
667 if (!rinfo || !rinfo->dir_nr)
668 return true;
669 chunk_offset = rinfo->dir_entries[0].offset;
670 return new_pos < chunk_offset ||
671 is_hash_order(new_pos) != is_hash_order(chunk_offset);
672 }
673
674 static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
675 {
676 struct ceph_dir_file_info *dfi = file->private_data;
677 struct inode *inode = file->f_mapping->host;
678 struct ceph_client *cl = ceph_inode_to_client(inode);
679 loff_t retval;
680
681 inode_lock(inode);
682 retval = -EINVAL;
683 switch (whence) {
684 case SEEK_CUR:
685 offset += file->f_pos;
686 break;
687 case SEEK_SET:
688 break;
689 case SEEK_END:
690 retval = -EOPNOTSUPP;
691 goto out;
692 default:
693 goto out;
694 }
695
696 if (offset >= 0) {
697 if (need_reset_readdir(dfi, offset)) {
698 doutc(cl, "%p %llx.%llx dropping %p content\n",
699 inode, ceph_vinop(inode), file);
700 reset_readdir(dfi);
701 } else if (is_hash_order(offset) && offset > file->f_pos) {
702 /* for hash offset, we don't know if a forward seek
703 * is within same frag */
704 dfi->dir_release_count = 0;
705 dfi->readdir_cache_idx = -1;
706 }
707
708 if (offset != file->f_pos) {
709 file->f_pos = offset;
710 file->f_version = 0;
711 dfi->file_info.flags &= ~CEPH_F_ATEND;
712 }
713 retval = offset;
714 }
715 out:
716 inode_unlock(inode);
717 return retval;
718 }
719
720 /*
721 * Handle lookups for the hidden .snap directory.
722 */
723 struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
724 struct dentry *dentry)
725 {
726 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);
727 struct inode *parent = d_inode(dentry->d_parent); /* we hold i_rwsem */
728 struct ceph_client *cl = ceph_inode_to_client(parent);
729
730 /* .snap dir? */
731 if (ceph_snap(parent) == CEPH_NOSNAP &&
732 strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {
733 struct dentry *res;
734 struct inode *inode = ceph_get_snapdir(parent);
735
736 res = d_splice_alias(inode, dentry);
737 doutc(cl, "ENOENT on snapdir %p '%pd', linking to "
738 "snapdir %p %llx.%llx. Spliced dentry %p\n",
739 dentry, dentry, inode, ceph_vinop(inode), res);
740 if (res)
741 dentry = res;
742 }
743 return dentry;
744 }
745
746 /*
747 * Figure out final result of a lookup/open request.
748 *
749 * Mainly, make sure we return the final req->r_dentry (if it already
750 * existed) in place of the original VFS-provided dentry when they
751 * differ.
752 *
753 * Gracefully handle the case where the MDS replies with -ENOENT and
754 * no trace (which it may do, at its discretion, e.g., if it doesn't
755 * care to issue a lease on the negative dentry).
756 */
757 struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
758 struct dentry *dentry, int err)
759 {
760 struct ceph_client *cl = req->r_mdsc->fsc->client;
761
762 if (err == -ENOENT) {
763 /* no trace? */
764 err = 0;
765 if (!req->r_reply_info.head->is_dentry) {
766 doutc(cl,
767 "ENOENT and no trace, dentry %p inode %llx.%llx\n",
768 dentry, ceph_vinop(d_inode(dentry)));
769 if (d_really_is_positive(dentry)) {
770 d_drop(dentry);
771 err = -ENOENT;
772 } else {
773 d_add(dentry, NULL);
774 }
775 }
776 }
777 if (err)
778 dentry = ERR_PTR(err);
779 else if (dentry != req->r_dentry)
780 dentry = dget(req->r_dentry); /* we got spliced */
781 else
782 dentry = NULL;
783 return dentry;
784 }
785
786 static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
787 {
788 return ceph_ino(inode) == CEPH_INO_ROOT &&
789 strncmp(dentry->d_name.name, ".ceph", 5) == 0;
790 }
791
792 /*
793 * Look up a single dir entry. If there is a lookup intent, inform
794 * the MDS so that it gets our 'caps wanted' value in a single op.
795 */
796 static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
797 unsigned int flags)
798 {
799 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dir->i_sb);
800 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
801 struct ceph_client *cl = fsc->client;
802 struct ceph_mds_request *req;
803 int op;
804 int mask;
805 int err;
806
807 doutc(cl, "%p %llx.%llx/'%pd' dentry %p\n", dir, ceph_vinop(dir),
808 dentry, dentry);
809
810 if (dentry->d_name.len > NAME_MAX)
811 return ERR_PTR(-ENAMETOOLONG);
812
813 if (IS_ENCRYPTED(dir)) {
814 bool had_key = fscrypt_has_encryption_key(dir);
815
816 err = fscrypt_prepare_lookup_partial(dir, dentry);
817 if (err < 0)
818 return ERR_PTR(err);
819
820 /* mark directory as incomplete if it has been unlocked */
821 if (!had_key && fscrypt_has_encryption_key(dir))
822 ceph_dir_clear_complete(dir);
823 }
824
825 /* can we conclude ENOENT locally? */
826 if (d_really_is_negative(dentry)) {
827 struct ceph_inode_info *ci = ceph_inode(dir);
828 struct ceph_dentry_info *di = ceph_dentry(dentry);
829
830 spin_lock(&ci->i_ceph_lock);
831 doutc(cl, " dir %llx.%llx flags are 0x%lx\n",
832 ceph_vinop(dir), ci->i_ceph_flags);
833 if (strncmp(dentry->d_name.name,
834 fsc->mount_options->snapdir_name,
835 dentry->d_name.len) &&
836 !is_root_ceph_dentry(dir, dentry) &&
837 ceph_test_mount_opt(fsc, DCACHE) &&
838 __ceph_dir_is_complete(ci) &&
839 __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
840 __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
841 spin_unlock(&ci->i_ceph_lock);
842 doutc(cl, " dir %llx.%llx complete, -ENOENT\n",
843 ceph_vinop(dir));
844 d_add(dentry, NULL);
845 di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
846 return NULL;
847 }
848 spin_unlock(&ci->i_ceph_lock);
849 }
850
851 op = ceph_snap(dir) == CEPH_SNAPDIR ?
852 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
853 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
854 if (IS_ERR(req))
855 return ERR_CAST(req);
856 req->r_dentry = dget(dentry);
857 req->r_num_caps = 2;
858
859 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
860 if (ceph_security_xattr_wanted(dir))
861 mask |= CEPH_CAP_XATTR_SHARED;
862 req->r_args.getattr.mask = cpu_to_le32(mask);
863
864 ihold(dir);
865 req->r_parent = dir;
866 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
867 err = ceph_mdsc_do_request(mdsc, NULL, req);
868 if (err == -ENOENT) {
869 struct dentry *res;
870
871 res = ceph_handle_snapdir(req, dentry);
872 if (IS_ERR(res)) {
873 err = PTR_ERR(res);
874 } else {
875 dentry = res;
876 err = 0;
877 }
878 }
879 dentry = ceph_finish_lookup(req, dentry, err);
880 ceph_mdsc_put_request(req); /* will dput(dentry) */
881 doutc(cl, "result=%p\n", dentry);
882 return dentry;
883 }
884
885 /*
886 * If we do a create but get no trace back from the MDS, follow up with
887 * a lookup (the VFS expects us to link up the provided dentry).
888 */
889 int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
890 {
891 struct dentry *result = ceph_lookup(dir, dentry, 0);
892
893 if (result && !IS_ERR(result)) {
894 /*
895 * We created the item, then did a lookup, and found
896 * it was already linked to another inode we already
897 * had in our cache (and thus got spliced). To not
898 * confuse VFS (especially when inode is a directory),
899 * we don't link our dentry to that inode, return an
900 * error instead.
901 *
902 * This event should be rare and it happens only when
903 * we talk to old MDS. Recent MDS does not send traceless
904 * reply for request that creates new inode.
905 */
906 d_drop(result);
907 return -ESTALE;
908 }
909 return PTR_ERR(result);
910 }
911
912 static int ceph_mknod(struct mnt_idmap *idmap, struct inode *dir,
913 struct dentry *dentry, umode_t mode, dev_t rdev)
914 {
915 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
916 struct ceph_client *cl = mdsc->fsc->client;
917 struct ceph_mds_request *req;
918 struct ceph_acl_sec_ctx as_ctx = {};
919 int err;
920
921 if (ceph_snap(dir) != CEPH_NOSNAP)
922 return -EROFS;
923
924 err = ceph_wait_on_conflict_unlink(dentry);
925 if (err)
926 return err;
927
928 if (ceph_quota_is_max_files_exceeded(dir)) {
929 err = -EDQUOT;
930 goto out;
931 }
932
933 doutc(cl, "%p %llx.%llx/'%pd' dentry %p mode 0%ho rdev %d\n",
934 dir, ceph_vinop(dir), dentry, dentry, mode, rdev);
935 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
936 if (IS_ERR(req)) {
937 err = PTR_ERR(req);
938 goto out;
939 }
940
941 req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);
942 if (IS_ERR(req->r_new_inode)) {
943 err = PTR_ERR(req->r_new_inode);
944 req->r_new_inode = NULL;
945 goto out_req;
946 }
947
948 if (S_ISREG(mode) && IS_ENCRYPTED(dir))
949 set_bit(CEPH_MDS_R_FSCRYPT_FILE, &req->r_req_flags);
950
951 req->r_dentry = dget(dentry);
952 req->r_num_caps = 2;
953 req->r_parent = dir;
954 ihold(dir);
955 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
956 req->r_mnt_idmap = mnt_idmap_get(idmap);
957 req->r_args.mknod.mode = cpu_to_le32(mode);
958 req->r_args.mknod.rdev = cpu_to_le32(rdev);
959 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
960 CEPH_CAP_XATTR_EXCL;
961 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
962
963 ceph_as_ctx_to_req(req, &as_ctx);
964
965 err = ceph_mdsc_do_request(mdsc, dir, req);
966 if (!err && !req->r_reply_info.head->is_dentry)
967 err = ceph_handle_notrace_create(dir, dentry);
968 out_req:
969 ceph_mdsc_put_request(req);
970 out:
971 if (!err)
972 ceph_init_inode_acls(d_inode(dentry), &as_ctx);
973 else
974 d_drop(dentry);
975 ceph_release_acl_sec_ctx(&as_ctx);
976 return err;
977 }
978
979 static int ceph_create(struct mnt_idmap *idmap, struct inode *dir,
980 struct dentry *dentry, umode_t mode, bool excl)
981 {
982 return ceph_mknod(idmap, dir, dentry, mode, 0);
983 }
984
985 #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
986 static int prep_encrypted_symlink_target(struct ceph_mds_request *req,
987 const char *dest)
988 {
989 int err;
990 int len = strlen(dest);
991 struct fscrypt_str osd_link = FSTR_INIT(NULL, 0);
992
993 err = fscrypt_prepare_symlink(req->r_parent, dest, len, PATH_MAX,
994 &osd_link);
995 if (err)
996 goto out;
997
998 err = fscrypt_encrypt_symlink(req->r_new_inode, dest, len, &osd_link);
999 if (err)
1000 goto out;
1001
1002 req->r_path2 = kmalloc(CEPH_BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL);
1003 if (!req->r_path2) {
1004 err = -ENOMEM;
1005 goto out;
1006 }
1007
1008 len = ceph_base64_encode(osd_link.name, osd_link.len, req->r_path2);
1009 req->r_path2[len] = '\0';
1010 out:
1011 fscrypt_fname_free_buffer(&osd_link);
1012 return err;
1013 }
1014 #else
1015 static int prep_encrypted_symlink_target(struct ceph_mds_request *req,
1016 const char *dest)
1017 {
1018 return -EOPNOTSUPP;
1019 }
1020 #endif
1021
1022 static int ceph_symlink(struct mnt_idmap *idmap, struct inode *dir,
1023 struct dentry *dentry, const char *dest)
1024 {
1025 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
1026 struct ceph_client *cl = mdsc->fsc->client;
1027 struct ceph_mds_request *req;
1028 struct ceph_acl_sec_ctx as_ctx = {};
1029 umode_t mode = S_IFLNK | 0777;
1030 int err;
1031
1032 if (ceph_snap(dir) != CEPH_NOSNAP)
1033 return -EROFS;
1034
1035 err = ceph_wait_on_conflict_unlink(dentry);
1036 if (err)
1037 return err;
1038
1039 if (ceph_quota_is_max_files_exceeded(dir)) {
1040 err = -EDQUOT;
1041 goto out;
1042 }
1043
1044 doutc(cl, "%p %llx.%llx/'%pd' to '%s'\n", dir, ceph_vinop(dir), dentry,
1045 dest);
1046 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
1047 if (IS_ERR(req)) {
1048 err = PTR_ERR(req);
1049 goto out;
1050 }
1051
1052 req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);
1053 if (IS_ERR(req->r_new_inode)) {
1054 err = PTR_ERR(req->r_new_inode);
1055 req->r_new_inode = NULL;
1056 goto out_req;
1057 }
1058
1059 req->r_parent = dir;
1060 ihold(dir);
1061
1062 if (IS_ENCRYPTED(req->r_new_inode)) {
1063 err = prep_encrypted_symlink_target(req, dest);
1064 if (err)
1065 goto out_req;
1066 } else {
1067 req->r_path2 = kstrdup(dest, GFP_KERNEL);
1068 if (!req->r_path2) {
1069 err = -ENOMEM;
1070 goto out_req;
1071 }
1072 }
1073
1074 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1075 req->r_mnt_idmap = mnt_idmap_get(idmap);
1076 req->r_dentry = dget(dentry);
1077 req->r_num_caps = 2;
1078 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
1079 CEPH_CAP_XATTR_EXCL;
1080 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1081
1082 ceph_as_ctx_to_req(req, &as_ctx);
1083
1084 err = ceph_mdsc_do_request(mdsc, dir, req);
1085 if (!err && !req->r_reply_info.head->is_dentry)
1086 err = ceph_handle_notrace_create(dir, dentry);
1087 out_req:
1088 ceph_mdsc_put_request(req);
1089 out:
1090 if (err)
1091 d_drop(dentry);
1092 ceph_release_acl_sec_ctx(&as_ctx);
1093 return err;
1094 }
1095
1096 static int ceph_mkdir(struct mnt_idmap *idmap, struct inode *dir,
1097 struct dentry *dentry, umode_t mode)
1098 {
1099 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
1100 struct ceph_client *cl = mdsc->fsc->client;
1101 struct ceph_mds_request *req;
1102 struct ceph_acl_sec_ctx as_ctx = {};
1103 int err;
1104 int op;
1105
1106 err = ceph_wait_on_conflict_unlink(dentry);
1107 if (err)
1108 return err;
1109
1110 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1111 /* mkdir .snap/foo is a MKSNAP */
1112 op = CEPH_MDS_OP_MKSNAP;
1113 doutc(cl, "mksnap %llx.%llx/'%pd' dentry %p\n",
1114 ceph_vinop(dir), dentry, dentry);
1115 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1116 doutc(cl, "mkdir %llx.%llx/'%pd' dentry %p mode 0%ho\n",
1117 ceph_vinop(dir), dentry, dentry, mode);
1118 op = CEPH_MDS_OP_MKDIR;
1119 } else {
1120 err = -EROFS;
1121 goto out;
1122 }
1123
1124 if (op == CEPH_MDS_OP_MKDIR &&
1125 ceph_quota_is_max_files_exceeded(dir)) {
1126 err = -EDQUOT;
1127 goto out;
1128 }
1129 if ((op == CEPH_MDS_OP_MKSNAP) && IS_ENCRYPTED(dir) &&
1130 !fscrypt_has_encryption_key(dir)) {
1131 err = -ENOKEY;
1132 goto out;
1133 }
1134
1135
1136 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1137 if (IS_ERR(req)) {
1138 err = PTR_ERR(req);
1139 goto out;
1140 }
1141
1142 mode |= S_IFDIR;
1143 req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);
1144 if (IS_ERR(req->r_new_inode)) {
1145 err = PTR_ERR(req->r_new_inode);
1146 req->r_new_inode = NULL;
1147 goto out_req;
1148 }
1149
1150 req->r_dentry = dget(dentry);
1151 req->r_num_caps = 2;
1152 req->r_parent = dir;
1153 ihold(dir);
1154 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1155 if (op == CEPH_MDS_OP_MKDIR)
1156 req->r_mnt_idmap = mnt_idmap_get(idmap);
1157 req->r_args.mkdir.mode = cpu_to_le32(mode);
1158 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
1159 CEPH_CAP_XATTR_EXCL;
1160 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1161
1162 ceph_as_ctx_to_req(req, &as_ctx);
1163
1164 err = ceph_mdsc_do_request(mdsc, dir, req);
1165 if (!err &&
1166 !req->r_reply_info.head->is_target &&
1167 !req->r_reply_info.head->is_dentry)
1168 err = ceph_handle_notrace_create(dir, dentry);
1169 out_req:
1170 ceph_mdsc_put_request(req);
1171 out:
1172 if (!err)
1173 ceph_init_inode_acls(d_inode(dentry), &as_ctx);
1174 else
1175 d_drop(dentry);
1176 ceph_release_acl_sec_ctx(&as_ctx);
1177 return err;
1178 }
1179
1180 static int ceph_link(struct dentry *old_dentry, struct inode *dir,
1181 struct dentry *dentry)
1182 {
1183 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
1184 struct ceph_client *cl = mdsc->fsc->client;
1185 struct ceph_mds_request *req;
1186 int err;
1187
1188 if (dentry->d_flags & DCACHE_DISCONNECTED)
1189 return -EINVAL;
1190
1191 err = ceph_wait_on_conflict_unlink(dentry);
1192 if (err)
1193 return err;
1194
1195 if (ceph_snap(dir) != CEPH_NOSNAP)
1196 return -EROFS;
1197
1198 err = fscrypt_prepare_link(old_dentry, dir, dentry);
1199 if (err)
1200 return err;
1201
1202 doutc(cl, "%p %llx.%llx/'%pd' to '%pd'\n", dir, ceph_vinop(dir),
1203 old_dentry, dentry);
1204 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
1205 if (IS_ERR(req)) {
1206 d_drop(dentry);
1207 return PTR_ERR(req);
1208 }
1209 req->r_dentry = dget(dentry);
1210 req->r_num_caps = 2;
1211 req->r_old_dentry = dget(old_dentry);
1212 /*
1213 * The old_dentry maybe a DCACHE_DISCONNECTED dentry, then we
1214 * will just pass the ino# to MDSs.
1215 */
1216 if (old_dentry->d_flags & DCACHE_DISCONNECTED)
1217 req->r_ino2 = ceph_vino(d_inode(old_dentry));
1218 req->r_parent = dir;
1219 ihold(dir);
1220 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1221 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1222 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1223 /* release LINK_SHARED on source inode (mds will lock it) */
1224 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1225 err = ceph_mdsc_do_request(mdsc, dir, req);
1226 if (err) {
1227 d_drop(dentry);
1228 } else if (!req->r_reply_info.head->is_dentry) {
1229 ihold(d_inode(old_dentry));
1230 d_instantiate(dentry, d_inode(old_dentry));
1231 }
1232 ceph_mdsc_put_request(req);
1233 return err;
1234 }
1235
1236 static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,
1237 struct ceph_mds_request *req)
1238 {
1239 struct dentry *dentry = req->r_dentry;
1240 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);
1241 struct ceph_client *cl = fsc->client;
1242 struct ceph_dentry_info *di = ceph_dentry(dentry);
1243 int result = req->r_err ? req->r_err :
1244 le32_to_cpu(req->r_reply_info.head->result);
1245
1246 if (!test_bit(CEPH_DENTRY_ASYNC_UNLINK_BIT, &di->flags))
1247 pr_warn_client(cl,
1248 "dentry %p:%pd async unlink bit is not set\n",
1249 dentry, dentry);
1250
1251 spin_lock(&fsc->async_unlink_conflict_lock);
1252 hash_del_rcu(&di->hnode);
1253 spin_unlock(&fsc->async_unlink_conflict_lock);
1254
1255 spin_lock(&dentry->d_lock);
1256 di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1257 wake_up_bit(&di->flags, CEPH_DENTRY_ASYNC_UNLINK_BIT);
1258 spin_unlock(&dentry->d_lock);
1259
1260 synchronize_rcu();
1261
1262 if (result == -EJUKEBOX)
1263 goto out;
1264
1265 /* If op failed, mark everyone involved for errors */
1266 if (result) {
1267 int pathlen = 0;
1268 u64 base = 0;
1269 char *path = ceph_mdsc_build_path(mdsc, dentry, &pathlen,
1270 &base, 0);
1271
1272 /* mark error on parent + clear complete */
1273 mapping_set_error(req->r_parent->i_mapping, result);
1274 ceph_dir_clear_complete(req->r_parent);
1275
1276 /* drop the dentry -- we don't know its status */
1277 if (!d_unhashed(dentry))
1278 d_drop(dentry);
1279
1280 /* mark inode itself for an error (since metadata is bogus) */
1281 mapping_set_error(req->r_old_inode->i_mapping, result);
1282
1283 pr_warn_client(cl, "failure path=(%llx)%s result=%d!\n",
1284 base, IS_ERR(path) ? "<<bad>>" : path, result);
1285 ceph_mdsc_free_path(path, pathlen);
1286 }
1287 out:
1288 iput(req->r_old_inode);
1289 ceph_mdsc_release_dir_caps(req);
1290 }
1291
1292 static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry)
1293 {
1294 struct ceph_inode_info *ci = ceph_inode(dir);
1295 struct ceph_dentry_info *di;
1296 int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK;
1297
1298 spin_lock(&ci->i_ceph_lock);
1299 if ((__ceph_caps_issued(ci, NULL) & want) == want) {
1300 ceph_take_cap_refs(ci, want, false);
1301 got = want;
1302 }
1303 spin_unlock(&ci->i_ceph_lock);
1304
1305 /* If we didn't get anything, return 0 */
1306 if (!got)
1307 return 0;
1308
1309 spin_lock(&dentry->d_lock);
1310 di = ceph_dentry(dentry);
1311 /*
1312 * - We are holding Fx, which implies Fs caps.
1313 * - Only support async unlink for primary linkage
1314 */
1315 if (atomic_read(&ci->i_shared_gen) != di->lease_shared_gen ||
1316 !(di->flags & CEPH_DENTRY_PRIMARY_LINK))
1317 want = 0;
1318 spin_unlock(&dentry->d_lock);
1319
1320 /* Do we still want what we've got? */
1321 if (want == got)
1322 return got;
1323
1324 ceph_put_cap_refs(ci, got);
1325 return 0;
1326 }
1327
1328 /*
1329 * rmdir and unlink are differ only by the metadata op code
1330 */
1331 static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1332 {
1333 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dir->i_sb);
1334 struct ceph_client *cl = fsc->client;
1335 struct ceph_mds_client *mdsc = fsc->mdsc;
1336 struct inode *inode = d_inode(dentry);
1337 struct ceph_mds_request *req;
1338 bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
1339 struct dentry *dn;
1340 int err = -EROFS;
1341 int op;
1342 char *path;
1343 int pathlen;
1344 u64 pathbase;
1345
1346 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1347 /* rmdir .snap/foo is RMSNAP */
1348 doutc(cl, "rmsnap %llx.%llx/'%pd' dn\n", ceph_vinop(dir),
1349 dentry);
1350 op = CEPH_MDS_OP_RMSNAP;
1351 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1352 doutc(cl, "unlink/rmdir %llx.%llx/'%pd' inode %llx.%llx\n",
1353 ceph_vinop(dir), dentry, ceph_vinop(inode));
1354 op = d_is_dir(dentry) ?
1355 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1356 } else
1357 goto out;
1358
1359 dn = d_find_alias(dir);
1360 if (!dn) {
1361 try_async = false;
1362 } else {
1363 path = ceph_mdsc_build_path(mdsc, dn, &pathlen, &pathbase, 0);
1364 if (IS_ERR(path)) {
1365 try_async = false;
1366 err = 0;
1367 } else {
1368 err = ceph_mds_check_access(mdsc, path, MAY_WRITE);
1369 }
1370 ceph_mdsc_free_path(path, pathlen);
1371 dput(dn);
1372
1373 /* For none EACCES cases will let the MDS do the mds auth check */
1374 if (err == -EACCES) {
1375 return err;
1376 } else if (err < 0) {
1377 try_async = false;
1378 err = 0;
1379 }
1380 }
1381
1382 retry:
1383 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1384 if (IS_ERR(req)) {
1385 err = PTR_ERR(req);
1386 goto out;
1387 }
1388 req->r_dentry = dget(dentry);
1389 req->r_num_caps = 2;
1390 req->r_parent = dir;
1391 ihold(dir);
1392 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1393 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1394 req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1395
1396 if (try_async && op == CEPH_MDS_OP_UNLINK &&
1397 (req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) {
1398 struct ceph_dentry_info *di = ceph_dentry(dentry);
1399
1400 doutc(cl, "async unlink on %llx.%llx/'%pd' caps=%s",
1401 ceph_vinop(dir), dentry,
1402 ceph_cap_string(req->r_dir_caps));
1403 set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
1404 req->r_callback = ceph_async_unlink_cb;
1405 req->r_old_inode = d_inode(dentry);
1406 ihold(req->r_old_inode);
1407
1408 spin_lock(&dentry->d_lock);
1409 di->flags |= CEPH_DENTRY_ASYNC_UNLINK;
1410 spin_unlock(&dentry->d_lock);
1411
1412 spin_lock(&fsc->async_unlink_conflict_lock);
1413 hash_add_rcu(fsc->async_unlink_conflict, &di->hnode,
1414 dentry->d_name.hash);
1415 spin_unlock(&fsc->async_unlink_conflict_lock);
1416
1417 err = ceph_mdsc_submit_request(mdsc, dir, req);
1418 if (!err) {
1419 /*
1420 * We have enough caps, so we assume that the unlink
1421 * will succeed. Fix up the target inode and dcache.
1422 */
1423 drop_nlink(inode);
1424 d_delete(dentry);
1425 } else {
1426 spin_lock(&fsc->async_unlink_conflict_lock);
1427 hash_del_rcu(&di->hnode);
1428 spin_unlock(&fsc->async_unlink_conflict_lock);
1429
1430 spin_lock(&dentry->d_lock);
1431 di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1432 spin_unlock(&dentry->d_lock);
1433
1434 if (err == -EJUKEBOX) {
1435 try_async = false;
1436 ceph_mdsc_put_request(req);
1437 goto retry;
1438 }
1439 }
1440 } else {
1441 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1442 err = ceph_mdsc_do_request(mdsc, dir, req);
1443 if (!err && !req->r_reply_info.head->is_dentry)
1444 d_delete(dentry);
1445 }
1446
1447 ceph_mdsc_put_request(req);
1448 out:
1449 return err;
1450 }
1451
1452 static int ceph_rename(struct mnt_idmap *idmap, struct inode *old_dir,
1453 struct dentry *old_dentry, struct inode *new_dir,
1454 struct dentry *new_dentry, unsigned int flags)
1455 {
1456 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old_dir->i_sb);
1457 struct ceph_client *cl = mdsc->fsc->client;
1458 struct ceph_mds_request *req;
1459 int op = CEPH_MDS_OP_RENAME;
1460 int err;
1461
1462 if (flags)
1463 return -EINVAL;
1464
1465 if (ceph_snap(old_dir) != ceph_snap(new_dir))
1466 return -EXDEV;
1467 if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1468 if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1469 op = CEPH_MDS_OP_RENAMESNAP;
1470 else
1471 return -EROFS;
1472 }
1473 /* don't allow cross-quota renames */
1474 if ((old_dir != new_dir) &&
1475 (!ceph_quota_is_same_realm(old_dir, new_dir)))
1476 return -EXDEV;
1477
1478 err = ceph_wait_on_conflict_unlink(new_dentry);
1479 if (err)
1480 return err;
1481
1482 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
1483 flags);
1484 if (err)
1485 return err;
1486
1487 doutc(cl, "%llx.%llx/'%pd' to %llx.%llx/'%pd'\n",
1488 ceph_vinop(old_dir), old_dentry, ceph_vinop(new_dir),
1489 new_dentry);
1490 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1491 if (IS_ERR(req))
1492 return PTR_ERR(req);
1493 ihold(old_dir);
1494 req->r_dentry = dget(new_dentry);
1495 req->r_num_caps = 2;
1496 req->r_old_dentry = dget(old_dentry);
1497 req->r_old_dentry_dir = old_dir;
1498 req->r_parent = new_dir;
1499 ihold(new_dir);
1500 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1501 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1502 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1503 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1504 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1505 /* release LINK_RDCACHE on source inode (mds will lock it) */
1506 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1507 if (d_really_is_positive(new_dentry)) {
1508 req->r_inode_drop =
1509 ceph_drop_caps_for_unlink(d_inode(new_dentry));
1510 }
1511 err = ceph_mdsc_do_request(mdsc, old_dir, req);
1512 if (!err && !req->r_reply_info.head->is_dentry) {
1513 /*
1514 * Normally d_move() is done by fill_trace (called by
1515 * do_request, above). If there is no trace, we need
1516 * to do it here.
1517 */
1518 d_move(old_dentry, new_dentry);
1519 }
1520 ceph_mdsc_put_request(req);
1521 return err;
1522 }
1523
1524 /*
1525 * Move dentry to tail of mdsc->dentry_leases list when lease is updated.
1526 * Leases at front of the list will expire first. (Assume all leases have
1527 * similar duration)
1528 *
1529 * Called under dentry->d_lock.
1530 */
1531 void __ceph_dentry_lease_touch(struct ceph_dentry_info *di)
1532 {
1533 struct dentry *dn = di->dentry;
1534 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dn->d_sb)->mdsc;
1535 struct ceph_client *cl = mdsc->fsc->client;
1536
1537 doutc(cl, "%p %p '%pd'\n", di, dn, dn);
1538
1539 di->flags |= CEPH_DENTRY_LEASE_LIST;
1540 if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1541 di->flags |= CEPH_DENTRY_REFERENCED;
1542 return;
1543 }
1544
1545 spin_lock(&mdsc->dentry_list_lock);
1546 list_move_tail(&di->lease_list, &mdsc->dentry_leases);
1547 spin_unlock(&mdsc->dentry_list_lock);
1548 }
1549
1550 static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc,
1551 struct ceph_dentry_info *di)
1552 {
1553 di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED);
1554 di->lease_gen = 0;
1555 di->time = jiffies;
1556 list_move_tail(&di->lease_list, &mdsc->dentry_dir_leases);
1557 }
1558
1559 /*
1560 * When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases
1561 * list if it's not in the list, otherwise set 'referenced' flag.
1562 *
1563 * Called under dentry->d_lock.
1564 */
1565 void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di)
1566 {
1567 struct dentry *dn = di->dentry;
1568 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dn->d_sb)->mdsc;
1569 struct ceph_client *cl = mdsc->fsc->client;
1570
1571 doutc(cl, "%p %p '%pd' (offset 0x%llx)\n", di, dn, dn, di->offset);
1572
1573 if (!list_empty(&di->lease_list)) {
1574 if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1575 /* don't remove dentry from dentry lease list
1576 * if its lease is valid */
1577 if (__dentry_lease_is_valid(di))
1578 return;
1579 } else {
1580 di->flags |= CEPH_DENTRY_REFERENCED;
1581 return;
1582 }
1583 }
1584
1585 if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1586 di->flags |= CEPH_DENTRY_REFERENCED;
1587 di->flags &= ~CEPH_DENTRY_LEASE_LIST;
1588 return;
1589 }
1590
1591 spin_lock(&mdsc->dentry_list_lock);
1592 __dentry_dir_lease_touch(mdsc, di);
1593 spin_unlock(&mdsc->dentry_list_lock);
1594 }
1595
1596 static void __dentry_lease_unlist(struct ceph_dentry_info *di)
1597 {
1598 struct ceph_mds_client *mdsc;
1599 if (di->flags & CEPH_DENTRY_SHRINK_LIST)
1600 return;
1601 if (list_empty(&di->lease_list))
1602 return;
1603
1604 mdsc = ceph_sb_to_fs_client(di->dentry->d_sb)->mdsc;
1605 spin_lock(&mdsc->dentry_list_lock);
1606 list_del_init(&di->lease_list);
1607 spin_unlock(&mdsc->dentry_list_lock);
1608 }
1609
1610 enum {
1611 KEEP = 0,
1612 DELETE = 1,
1613 TOUCH = 2,
1614 STOP = 4,
1615 };
1616
1617 struct ceph_lease_walk_control {
1618 bool dir_lease;
1619 bool expire_dir_lease;
1620 unsigned long nr_to_scan;
1621 unsigned long dir_lease_ttl;
1622 };
1623
1624 static int __dir_lease_check(const struct dentry *, struct ceph_lease_walk_control *);
1625 static int __dentry_lease_check(const struct dentry *);
1626
1627 static unsigned long
1628 __dentry_leases_walk(struct ceph_mds_client *mdsc,
1629 struct ceph_lease_walk_control *lwc)
1630 {
1631 struct ceph_dentry_info *di, *tmp;
1632 struct dentry *dentry, *last = NULL;
1633 struct list_head* list;
1634 LIST_HEAD(dispose);
1635 unsigned long freed = 0;
1636 int ret = 0;
1637
1638 list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases;
1639 spin_lock(&mdsc->dentry_list_lock);
1640 list_for_each_entry_safe(di, tmp, list, lease_list) {
1641 if (!lwc->nr_to_scan)
1642 break;
1643 --lwc->nr_to_scan;
1644
1645 dentry = di->dentry;
1646 if (last == dentry)
1647 break;
1648
1649 if (!spin_trylock(&dentry->d_lock))
1650 continue;
1651
1652 if (__lockref_is_dead(&dentry->d_lockref)) {
1653 list_del_init(&di->lease_list);
1654 goto next;
1655 }
1656
1657 if (lwc->dir_lease)
1658 ret = __dir_lease_check(dentry, lwc);
1659 else
1660 ret = __dentry_lease_check(dentry);
1661 if (ret & TOUCH) {
1662 /* move it into tail of dir lease list */
1663 __dentry_dir_lease_touch(mdsc, di);
1664 if (!last)
1665 last = dentry;
1666 }
1667 if (ret & DELETE) {
1668 /* stale lease */
1669 di->flags &= ~CEPH_DENTRY_REFERENCED;
1670 if (dentry->d_lockref.count > 0) {
1671 /* update_dentry_lease() will re-add
1672 * it to lease list, or
1673 * ceph_d_delete() will return 1 when
1674 * last reference is dropped */
1675 list_del_init(&di->lease_list);
1676 } else {
1677 di->flags |= CEPH_DENTRY_SHRINK_LIST;
1678 list_move_tail(&di->lease_list, &dispose);
1679 dget_dlock(dentry);
1680 }
1681 }
1682 next:
1683 spin_unlock(&dentry->d_lock);
1684 if (ret & STOP)
1685 break;
1686 }
1687 spin_unlock(&mdsc->dentry_list_lock);
1688
1689 while (!list_empty(&dispose)) {
1690 di = list_first_entry(&dispose, struct ceph_dentry_info,
1691 lease_list);
1692 dentry = di->dentry;
1693 spin_lock(&dentry->d_lock);
1694
1695 list_del_init(&di->lease_list);
1696 di->flags &= ~CEPH_DENTRY_SHRINK_LIST;
1697 if (di->flags & CEPH_DENTRY_REFERENCED) {
1698 spin_lock(&mdsc->dentry_list_lock);
1699 if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1700 list_add_tail(&di->lease_list,
1701 &mdsc->dentry_leases);
1702 } else {
1703 __dentry_dir_lease_touch(mdsc, di);
1704 }
1705 spin_unlock(&mdsc->dentry_list_lock);
1706 } else {
1707 freed++;
1708 }
1709
1710 spin_unlock(&dentry->d_lock);
1711 /* ceph_d_delete() does the trick */
1712 dput(dentry);
1713 }
1714 return freed;
1715 }
1716
1717 static int __dentry_lease_check(const struct dentry *dentry)
1718 {
1719 struct ceph_dentry_info *di = ceph_dentry(dentry);
1720 int ret;
1721
1722 if (__dentry_lease_is_valid(di))
1723 return STOP;
1724 ret = __dir_lease_try_check(dentry);
1725 if (ret == -EBUSY)
1726 return KEEP;
1727 if (ret > 0)
1728 return TOUCH;
1729 return DELETE;
1730 }
1731
1732 static int __dir_lease_check(const struct dentry *dentry,
1733 struct ceph_lease_walk_control *lwc)
1734 {
1735 struct ceph_dentry_info *di = ceph_dentry(dentry);
1736
1737 int ret = __dir_lease_try_check(dentry);
1738 if (ret == -EBUSY)
1739 return KEEP;
1740 if (ret > 0) {
1741 if (time_before(jiffies, di->time + lwc->dir_lease_ttl))
1742 return STOP;
1743 /* Move dentry to tail of dir lease list if we don't want
1744 * to delete it. So dentries in the list are checked in a
1745 * round robin manner */
1746 if (!lwc->expire_dir_lease)
1747 return TOUCH;
1748 if (dentry->d_lockref.count > 0 ||
1749 (di->flags & CEPH_DENTRY_REFERENCED))
1750 return TOUCH;
1751 /* invalidate dir lease */
1752 di->lease_shared_gen = 0;
1753 }
1754 return DELETE;
1755 }
1756
1757 int ceph_trim_dentries(struct ceph_mds_client *mdsc)
1758 {
1759 struct ceph_lease_walk_control lwc;
1760 unsigned long count;
1761 unsigned long freed;
1762
1763 spin_lock(&mdsc->caps_list_lock);
1764 if (mdsc->caps_use_max > 0 &&
1765 mdsc->caps_use_count > mdsc->caps_use_max)
1766 count = mdsc->caps_use_count - mdsc->caps_use_max;
1767 else
1768 count = 0;
1769 spin_unlock(&mdsc->caps_list_lock);
1770
1771 lwc.dir_lease = false;
1772 lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE * 2;
1773 freed = __dentry_leases_walk(mdsc, &lwc);
1774 if (!lwc.nr_to_scan) /* more invalid leases */
1775 return -EAGAIN;
1776
1777 if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE)
1778 lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE;
1779
1780 lwc.dir_lease = true;
1781 lwc.expire_dir_lease = freed < count;
1782 lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ;
1783 freed +=__dentry_leases_walk(mdsc, &lwc);
1784 if (!lwc.nr_to_scan) /* more to check */
1785 return -EAGAIN;
1786
1787 return freed > 0 ? 1 : 0;
1788 }
1789
1790 /*
1791 * Ensure a dentry lease will no longer revalidate.
1792 */
1793 void ceph_invalidate_dentry_lease(struct dentry *dentry)
1794 {
1795 struct ceph_dentry_info *di = ceph_dentry(dentry);
1796 spin_lock(&dentry->d_lock);
1797 di->time = jiffies;
1798 di->lease_shared_gen = 0;
1799 di->flags &= ~CEPH_DENTRY_PRIMARY_LINK;
1800 __dentry_lease_unlist(di);
1801 spin_unlock(&dentry->d_lock);
1802 }
1803
1804 /*
1805 * Check if dentry lease is valid. If not, delete the lease. Try to
1806 * renew if the least is more than half up.
1807 */
1808 static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)
1809 {
1810 struct ceph_mds_session *session;
1811
1812 if (!di->lease_gen)
1813 return false;
1814
1815 session = di->lease_session;
1816 if (session) {
1817 u32 gen;
1818 unsigned long ttl;
1819
1820 gen = atomic_read(&session->s_cap_gen);
1821 ttl = session->s_cap_ttl;
1822
1823 if (di->lease_gen == gen &&
1824 time_before(jiffies, ttl) &&
1825 time_before(jiffies, di->time))
1826 return true;
1827 }
1828 di->lease_gen = 0;
1829 return false;
1830 }
1831
1832 static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)
1833 {
1834 struct ceph_dentry_info *di;
1835 struct ceph_mds_session *session = NULL;
1836 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dentry->d_sb)->mdsc;
1837 struct ceph_client *cl = mdsc->fsc->client;
1838 u32 seq = 0;
1839 int valid = 0;
1840
1841 spin_lock(&dentry->d_lock);
1842 di = ceph_dentry(dentry);
1843 if (di && __dentry_lease_is_valid(di)) {
1844 valid = 1;
1845
1846 if (di->lease_renew_after &&
1847 time_after(jiffies, di->lease_renew_after)) {
1848 /*
1849 * We should renew. If we're in RCU walk mode
1850 * though, we can't do that so just return
1851 * -ECHILD.
1852 */
1853 if (flags & LOOKUP_RCU) {
1854 valid = -ECHILD;
1855 } else {
1856 session = ceph_get_mds_session(di->lease_session);
1857 seq = di->lease_seq;
1858 di->lease_renew_after = 0;
1859 di->lease_renew_from = jiffies;
1860 }
1861 }
1862 }
1863 spin_unlock(&dentry->d_lock);
1864
1865 if (session) {
1866 ceph_mdsc_lease_send_msg(session, dentry,
1867 CEPH_MDS_LEASE_RENEW, seq);
1868 ceph_put_mds_session(session);
1869 }
1870 doutc(cl, "dentry %p = %d\n", dentry, valid);
1871 return valid;
1872 }
1873
1874 /*
1875 * Called under dentry->d_lock.
1876 */
1877 static int __dir_lease_try_check(const struct dentry *dentry)
1878 {
1879 struct ceph_dentry_info *di = ceph_dentry(dentry);
1880 struct inode *dir;
1881 struct ceph_inode_info *ci;
1882 int valid = 0;
1883
1884 if (!di->lease_shared_gen)
1885 return 0;
1886 if (IS_ROOT(dentry))
1887 return 0;
1888
1889 dir = d_inode(dentry->d_parent);
1890 ci = ceph_inode(dir);
1891
1892 if (spin_trylock(&ci->i_ceph_lock)) {
1893 if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen &&
1894 __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 0))
1895 valid = 1;
1896 spin_unlock(&ci->i_ceph_lock);
1897 } else {
1898 valid = -EBUSY;
1899 }
1900
1901 if (!valid)
1902 di->lease_shared_gen = 0;
1903 return valid;
1904 }
1905
1906 /*
1907 * Check if directory-wide content lease/cap is valid.
1908 */
1909 static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry,
1910 struct ceph_mds_client *mdsc)
1911 {
1912 struct ceph_inode_info *ci = ceph_inode(dir);
1913 struct ceph_client *cl = mdsc->fsc->client;
1914 int valid;
1915 int shared_gen;
1916
1917 spin_lock(&ci->i_ceph_lock);
1918 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1919 if (valid) {
1920 __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
1921 shared_gen = atomic_read(&ci->i_shared_gen);
1922 }
1923 spin_unlock(&ci->i_ceph_lock);
1924 if (valid) {
1925 struct ceph_dentry_info *di;
1926 spin_lock(&dentry->d_lock);
1927 di = ceph_dentry(dentry);
1928 if (dir == d_inode(dentry->d_parent) &&
1929 di && di->lease_shared_gen == shared_gen)
1930 __ceph_dentry_dir_lease_touch(di);
1931 else
1932 valid = 0;
1933 spin_unlock(&dentry->d_lock);
1934 }
1935 doutc(cl, "dir %p %llx.%llx v%u dentry %p '%pd' = %d\n", dir,
1936 ceph_vinop(dir), (unsigned)atomic_read(&ci->i_shared_gen),
1937 dentry, dentry, valid);
1938 return valid;
1939 }
1940
1941 /*
1942 * Check if cached dentry can be trusted.
1943 */
1944 static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1945 {
1946 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dentry->d_sb)->mdsc;
1947 struct ceph_client *cl = mdsc->fsc->client;
1948 int valid = 0;
1949 struct dentry *parent;
1950 struct inode *dir, *inode;
1951
1952 valid = fscrypt_d_revalidate(dentry, flags);
1953 if (valid <= 0)
1954 return valid;
1955
1956 if (flags & LOOKUP_RCU) {
1957 parent = READ_ONCE(dentry->d_parent);
1958 dir = d_inode_rcu(parent);
1959 if (!dir)
1960 return -ECHILD;
1961 inode = d_inode_rcu(dentry);
1962 } else {
1963 parent = dget_parent(dentry);
1964 dir = d_inode(parent);
1965 inode = d_inode(dentry);
1966 }
1967
1968 doutc(cl, "%p '%pd' inode %p offset 0x%llx nokey %d\n",
1969 dentry, dentry, inode, ceph_dentry(dentry)->offset,
1970 !!(dentry->d_flags & DCACHE_NOKEY_NAME));
1971
1972 mdsc = ceph_sb_to_fs_client(dir->i_sb)->mdsc;
1973
1974 /* always trust cached snapped dentries, snapdir dentry */
1975 if (ceph_snap(dir) != CEPH_NOSNAP) {
1976 doutc(cl, "%p '%pd' inode %p is SNAPPED\n", dentry,
1977 dentry, inode);
1978 valid = 1;
1979 } else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1980 valid = 1;
1981 } else {
1982 valid = dentry_lease_is_valid(dentry, flags);
1983 if (valid == -ECHILD)
1984 return valid;
1985 if (valid || dir_lease_is_valid(dir, dentry, mdsc)) {
1986 if (inode)
1987 valid = ceph_is_any_caps(inode);
1988 else
1989 valid = 1;
1990 }
1991 }
1992
1993 if (!valid) {
1994 struct ceph_mds_request *req;
1995 int op, err;
1996 u32 mask;
1997
1998 if (flags & LOOKUP_RCU)
1999 return -ECHILD;
2000
2001 percpu_counter_inc(&mdsc->metric.d_lease_mis);
2002
2003 op = ceph_snap(dir) == CEPH_SNAPDIR ?
2004 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
2005 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
2006 if (!IS_ERR(req)) {
2007 req->r_dentry = dget(dentry);
2008 req->r_num_caps = 2;
2009 req->r_parent = dir;
2010 ihold(dir);
2011
2012 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
2013 if (ceph_security_xattr_wanted(dir))
2014 mask |= CEPH_CAP_XATTR_SHARED;
2015 req->r_args.getattr.mask = cpu_to_le32(mask);
2016
2017 err = ceph_mdsc_do_request(mdsc, NULL, req);
2018 switch (err) {
2019 case 0:
2020 if (d_really_is_positive(dentry) &&
2021 d_inode(dentry) == req->r_target_inode)
2022 valid = 1;
2023 break;
2024 case -ENOENT:
2025 if (d_really_is_negative(dentry))
2026 valid = 1;
2027 fallthrough;
2028 default:
2029 break;
2030 }
2031 ceph_mdsc_put_request(req);
2032 doutc(cl, "%p '%pd', lookup result=%d\n", dentry,
2033 dentry, err);
2034 }
2035 } else {
2036 percpu_counter_inc(&mdsc->metric.d_lease_hit);
2037 }
2038
2039 doutc(cl, "%p '%pd' %s\n", dentry, dentry, valid ? "valid" : "invalid");
2040 if (!valid)
2041 ceph_dir_clear_complete(dir);
2042
2043 if (!(flags & LOOKUP_RCU))
2044 dput(parent);
2045 return valid;
2046 }
2047
2048 /*
2049 * Delete unused dentry that doesn't have valid lease
2050 *
2051 * Called under dentry->d_lock.
2052 */
2053 static int ceph_d_delete(const struct dentry *dentry)
2054 {
2055 struct ceph_dentry_info *di;
2056
2057 /* won't release caps */
2058 if (d_really_is_negative(dentry))
2059 return 0;
2060 if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
2061 return 0;
2062 /* vaild lease? */
2063 di = ceph_dentry(dentry);
2064 if (di) {
2065 if (__dentry_lease_is_valid(di))
2066 return 0;
2067 if (__dir_lease_try_check(dentry))
2068 return 0;
2069 }
2070 return 1;
2071 }
2072
2073 /*
2074 * Release our ceph_dentry_info.
2075 */
2076 static void ceph_d_release(struct dentry *dentry)
2077 {
2078 struct ceph_dentry_info *di = ceph_dentry(dentry);
2079 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);
2080
2081 doutc(fsc->client, "dentry %p '%pd'\n", dentry, dentry);
2082
2083 atomic64_dec(&fsc->mdsc->metric.total_dentries);
2084
2085 spin_lock(&dentry->d_lock);
2086 __dentry_lease_unlist(di);
2087 dentry->d_fsdata = NULL;
2088 spin_unlock(&dentry->d_lock);
2089
2090 ceph_put_mds_session(di->lease_session);
2091 kmem_cache_free(ceph_dentry_cachep, di);
2092 }
2093
2094 /*
2095 * When the VFS prunes a dentry from the cache, we need to clear the
2096 * complete flag on the parent directory.
2097 *
2098 * Called under dentry->d_lock.
2099 */
2100 static void ceph_d_prune(struct dentry *dentry)
2101 {
2102 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);
2103 struct ceph_client *cl = mdsc->fsc->client;
2104 struct ceph_inode_info *dir_ci;
2105 struct ceph_dentry_info *di;
2106
2107 doutc(cl, "dentry %p '%pd'\n", dentry, dentry);
2108
2109 /* do we have a valid parent? */
2110 if (IS_ROOT(dentry))
2111 return;
2112
2113 /* we hold d_lock, so d_parent is stable */
2114 dir_ci = ceph_inode(d_inode(dentry->d_parent));
2115 if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
2116 return;
2117
2118 /* who calls d_delete() should also disable dcache readdir */
2119 if (d_really_is_negative(dentry))
2120 return;
2121
2122 /* d_fsdata does not get cleared until d_release */
2123 if (!d_unhashed(dentry)) {
2124 __ceph_dir_clear_complete(dir_ci);
2125 return;
2126 }
2127
2128 /* Disable dcache readdir just in case that someone called d_drop()
2129 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
2130 * properly (dcache readdir is still enabled) */
2131 di = ceph_dentry(dentry);
2132 if (di->offset > 0 &&
2133 di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
2134 __ceph_dir_clear_ordered(dir_ci);
2135 }
2136
2137 /*
2138 * read() on a dir. This weird interface hack only works if mounted
2139 * with '-o dirstat'.
2140 */
2141 static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
2142 loff_t *ppos)
2143 {
2144 struct ceph_dir_file_info *dfi = file->private_data;
2145 struct inode *inode = file_inode(file);
2146 struct ceph_inode_info *ci = ceph_inode(inode);
2147 int left;
2148 const int bufsize = 1024;
2149
2150 if (!ceph_test_mount_opt(ceph_sb_to_fs_client(inode->i_sb), DIRSTAT))
2151 return -EISDIR;
2152
2153 if (!dfi->dir_info) {
2154 dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
2155 if (!dfi->dir_info)
2156 return -ENOMEM;
2157 dfi->dir_info_len =
2158 snprintf(dfi->dir_info, bufsize,
2159 "entries: %20lld\n"
2160 " files: %20lld\n"
2161 " subdirs: %20lld\n"
2162 "rentries: %20lld\n"
2163 " rfiles: %20lld\n"
2164 " rsubdirs: %20lld\n"
2165 "rbytes: %20lld\n"
2166 "rctime: %10lld.%09ld\n",
2167 ci->i_files + ci->i_subdirs,
2168 ci->i_files,
2169 ci->i_subdirs,
2170 ci->i_rfiles + ci->i_rsubdirs,
2171 ci->i_rfiles,
2172 ci->i_rsubdirs,
2173 ci->i_rbytes,
2174 ci->i_rctime.tv_sec,
2175 ci->i_rctime.tv_nsec);
2176 }
2177
2178 if (*ppos >= dfi->dir_info_len)
2179 return 0;
2180 size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
2181 left = copy_to_user(buf, dfi->dir_info + *ppos, size);
2182 if (left == size)
2183 return -EFAULT;
2184 *ppos += (size - left);
2185 return size - left;
2186 }
2187
2188
2189
2190 /*
2191 * Return name hash for a given dentry. This is dependent on
2192 * the parent directory's hash function.
2193 */
2194 unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
2195 {
2196 struct ceph_inode_info *dci = ceph_inode(dir);
2197 unsigned hash;
2198
2199 switch (dci->i_dir_layout.dl_dir_hash) {
2200 case 0: /* for backward compat */
2201 case CEPH_STR_HASH_LINUX:
2202 return dn->d_name.hash;
2203
2204 default:
2205 spin_lock(&dn->d_lock);
2206 hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
2207 dn->d_name.name, dn->d_name.len);
2208 spin_unlock(&dn->d_lock);
2209 return hash;
2210 }
2211 }
2212
2213 WRAP_DIR_ITER(ceph_readdir) // FIXME!
2214 const struct file_operations ceph_dir_fops = {
2215 .read = ceph_read_dir,
2216 .iterate_shared = shared_ceph_readdir,
2217 .llseek = ceph_dir_llseek,
2218 .open = ceph_open,
2219 .release = ceph_release,
2220 .unlocked_ioctl = ceph_ioctl,
2221 .compat_ioctl = compat_ptr_ioctl,
2222 .fsync = ceph_fsync,
2223 .lock = ceph_lock,
2224 .flock = ceph_flock,
2225 };
2226
2227 const struct file_operations ceph_snapdir_fops = {
2228 .iterate_shared = shared_ceph_readdir,
2229 .llseek = ceph_dir_llseek,
2230 .open = ceph_open,
2231 .release = ceph_release,
2232 };
2233
2234 const struct inode_operations ceph_dir_iops = {
2235 .lookup = ceph_lookup,
2236 .permission = ceph_permission,
2237 .getattr = ceph_getattr,
2238 .setattr = ceph_setattr,
2239 .listxattr = ceph_listxattr,
2240 .get_inode_acl = ceph_get_acl,
2241 .set_acl = ceph_set_acl,
2242 .mknod = ceph_mknod,
2243 .symlink = ceph_symlink,
2244 .mkdir = ceph_mkdir,
2245 .link = ceph_link,
2246 .unlink = ceph_unlink,
2247 .rmdir = ceph_unlink,
2248 .rename = ceph_rename,
2249 .create = ceph_create,
2250 .atomic_open = ceph_atomic_open,
2251 };
2252
2253 const struct inode_operations ceph_snapdir_iops = {
2254 .lookup = ceph_lookup,
2255 .permission = ceph_permission,
2256 .getattr = ceph_getattr,
2257 .mkdir = ceph_mkdir,
2258 .rmdir = ceph_unlink,
2259 .rename = ceph_rename,
2260 };
2261
2262 const struct dentry_operations ceph_dentry_ops = {
2263 .d_revalidate = ceph_d_revalidate,
2264 .d_delete = ceph_d_delete,
2265 .d_release = ceph_d_release,
2266 .d_prune = ceph_d_prune,
2267 .d_init = ceph_d_init,
2268 };
2269
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