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