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Linux 4.19.133
[linux/fpc-iii.git] / fs / ceph / dir.c
blob7f3f64ba464fec59565f69a46327d6fd538ed85e
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 /*
33 * Initialize ceph dentry state.
34 */
35 static int ceph_d_init(struct dentry *dentry)
36 {
37 struct ceph_dentry_info *di;
38
39 di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
40 if (!di)
41 return -ENOMEM; /* oh well */
42
43 di->dentry = dentry;
44 di->lease_session = NULL;
45 di->time = jiffies;
46 dentry->d_fsdata = di;
47 ceph_dentry_lru_add(dentry);
48 return 0;
49 }
50
51 /*
52 * for f_pos for readdir:
53 * - hash order:
54 * (0xff << 52) | ((24 bits hash) << 28) |
55 * (the nth entry has hash collision);
56 * - frag+name order;
57 * ((frag value) << 28) | (the nth entry in frag);
58 */
59 #define OFFSET_BITS 28
60 #define OFFSET_MASK ((1 << OFFSET_BITS) - 1)
61 #define HASH_ORDER (0xffull << (OFFSET_BITS + 24))
62 loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
63 {
64 loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
65 if (hash_order)
66 fpos |= HASH_ORDER;
67 return fpos;
68 }
69
70 static bool is_hash_order(loff_t p)
71 {
72 return (p & HASH_ORDER) == HASH_ORDER;
73 }
74
75 static unsigned fpos_frag(loff_t p)
76 {
77 return p >> OFFSET_BITS;
78 }
79
80 static unsigned fpos_hash(loff_t p)
81 {
82 return ceph_frag_value(fpos_frag(p));
83 }
84
85 static unsigned fpos_off(loff_t p)
86 {
87 return p & OFFSET_MASK;
88 }
89
90 static int fpos_cmp(loff_t l, loff_t r)
91 {
92 int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
93 if (v)
94 return v;
95 return (int)(fpos_off(l) - fpos_off(r));
96 }
97
98 /*
99 * make note of the last dentry we read, so we can
100 * continue at the same lexicographical point,
101 * regardless of what dir changes take place on the
102 * server.
103 */
104 static int note_last_dentry(struct ceph_dir_file_info *dfi, const char *name,
105 int len, unsigned next_offset)
106 {
107 char *buf = kmalloc(len+1, GFP_KERNEL);
108 if (!buf)
109 return -ENOMEM;
110 kfree(dfi->last_name);
111 dfi->last_name = buf;
112 memcpy(dfi->last_name, name, len);
113 dfi->last_name[len] = 0;
114 dfi->next_offset = next_offset;
115 dout("note_last_dentry '%s'\n", dfi->last_name);
116 return 0;
117 }
118
119
120 static struct dentry *
121 __dcache_find_get_entry(struct dentry *parent, u64 idx,
122 struct ceph_readdir_cache_control *cache_ctl)
123 {
124 struct inode *dir = d_inode(parent);
125 struct dentry *dentry;
126 unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
127 loff_t ptr_pos = idx * sizeof(struct dentry *);
128 pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
129
130 if (ptr_pos >= i_size_read(dir))
131 return NULL;
132
133 if (!cache_ctl->page || ptr_pgoff != page_index(cache_ctl->page)) {
134 ceph_readdir_cache_release(cache_ctl);
135 cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
136 if (!cache_ctl->page) {
137 dout(" page %lu not found\n", ptr_pgoff);
138 return ERR_PTR(-EAGAIN);
139 }
140 /* reading/filling the cache are serialized by
141 i_mutex, no need to use page lock */
142 unlock_page(cache_ctl->page);
143 cache_ctl->dentries = kmap(cache_ctl->page);
144 }
145
146 cache_ctl->index = idx & idx_mask;
147
148 rcu_read_lock();
149 spin_lock(&parent->d_lock);
150 /* check i_size again here, because empty directory can be
151 * marked as complete while not holding the i_mutex. */
152 if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))
153 dentry = cache_ctl->dentries[cache_ctl->index];
154 else
155 dentry = NULL;
156 spin_unlock(&parent->d_lock);
157 if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
158 dentry = NULL;
159 rcu_read_unlock();
160 return dentry ? : ERR_PTR(-EAGAIN);
161 }
162
163 /*
164 * When possible, we try to satisfy a readdir by peeking at the
165 * dcache. We make this work by carefully ordering dentries on
166 * d_child when we initially get results back from the MDS, and
167 * falling back to a "normal" sync readdir if any dentries in the dir
168 * are dropped.
169 *
170 * Complete dir indicates that we have all dentries in the dir. It is
171 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
172 * the MDS if/when the directory is modified).
173 */
174 static int __dcache_readdir(struct file *file, struct dir_context *ctx,
175 int shared_gen)
176 {
177 struct ceph_dir_file_info *dfi = file->private_data;
178 struct dentry *parent = file->f_path.dentry;
179 struct inode *dir = d_inode(parent);
180 struct dentry *dentry, *last = NULL;
181 struct ceph_dentry_info *di;
182 struct ceph_readdir_cache_control cache_ctl = {};
183 u64 idx = 0;
184 int err = 0;
185
186 dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos);
187
188 /* search start position */
189 if (ctx->pos > 2) {
190 u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
191 while (count > 0) {
192 u64 step = count >> 1;
193 dentry = __dcache_find_get_entry(parent, idx + step,
194 &cache_ctl);
195 if (!dentry) {
196 /* use linar search */
197 idx = 0;
198 break;
199 }
200 if (IS_ERR(dentry)) {
201 err = PTR_ERR(dentry);
202 goto out;
203 }
204 di = ceph_dentry(dentry);
205 spin_lock(&dentry->d_lock);
206 if (fpos_cmp(di->offset, ctx->pos) < 0) {
207 idx += step + 1;
208 count -= step + 1;
209 } else {
210 count = step;
211 }
212 spin_unlock(&dentry->d_lock);
213 dput(dentry);
214 }
215
216 dout("__dcache_readdir %p cache idx %llu\n", dir, idx);
217 }
218
219
220 for (;;) {
221 bool emit_dentry = false;
222 dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
223 if (!dentry) {
224 dfi->file_info.flags |= CEPH_F_ATEND;
225 err = 0;
226 break;
227 }
228 if (IS_ERR(dentry)) {
229 err = PTR_ERR(dentry);
230 goto out;
231 }
232
233 spin_lock(&dentry->d_lock);
234 di = ceph_dentry(dentry);
235 if (d_unhashed(dentry) ||
236 d_really_is_negative(dentry) ||
237 di->lease_shared_gen != shared_gen) {
238 spin_unlock(&dentry->d_lock);
239 dput(dentry);
240 err = -EAGAIN;
241 goto out;
242 }
243 if (fpos_cmp(ctx->pos, di->offset) <= 0) {
244 emit_dentry = true;
245 }
246 spin_unlock(&dentry->d_lock);
247
248 if (emit_dentry) {
249 dout(" %llx dentry %p %pd %p\n", di->offset,
250 dentry, dentry, d_inode(dentry));
251 ctx->pos = di->offset;
252 if (!dir_emit(ctx, dentry->d_name.name,
253 dentry->d_name.len,
254 ceph_translate_ino(dentry->d_sb,
255 d_inode(dentry)->i_ino),
256 d_inode(dentry)->i_mode >> 12)) {
257 dput(dentry);
258 err = 0;
259 break;
260 }
261 ctx->pos++;
262
263 if (last)
264 dput(last);
265 last = dentry;
266 } else {
267 dput(dentry);
268 }
269 }
270 out:
271 ceph_readdir_cache_release(&cache_ctl);
272 if (last) {
273 int ret;
274 di = ceph_dentry(last);
275 ret = note_last_dentry(dfi, last->d_name.name, last->d_name.len,
276 fpos_off(di->offset) + 1);
277 if (ret < 0)
278 err = ret;
279 dput(last);
280 /* last_name no longer match cache index */
281 if (dfi->readdir_cache_idx >= 0) {
282 dfi->readdir_cache_idx = -1;
283 dfi->dir_release_count = 0;
284 }
285 }
286 return err;
287 }
288
289 static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)
290 {
291 if (!dfi->last_readdir)
292 return true;
293 if (is_hash_order(pos))
294 return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));
295 else
296 return dfi->frag != fpos_frag(pos);
297 }
298
299 static int ceph_readdir(struct file *file, struct dir_context *ctx)
300 {
301 struct ceph_dir_file_info *dfi = file->private_data;
302 struct inode *inode = file_inode(file);
303 struct ceph_inode_info *ci = ceph_inode(inode);
304 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
305 struct ceph_mds_client *mdsc = fsc->mdsc;
306 int i;
307 int err;
308 unsigned frag = -1;
309 struct ceph_mds_reply_info_parsed *rinfo;
310
311 dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
312 if (dfi->file_info.flags & CEPH_F_ATEND)
313 return 0;
314
315 /* always start with . and .. */
316 if (ctx->pos == 0) {
317 dout("readdir off 0 -> '.'\n");
318 if (!dir_emit(ctx, ".", 1,
319 ceph_translate_ino(inode->i_sb, inode->i_ino),
320 inode->i_mode >> 12))
321 return 0;
322 ctx->pos = 1;
323 }
324 if (ctx->pos == 1) {
325 ino_t ino = parent_ino(file->f_path.dentry);
326 dout("readdir off 1 -> '..'\n");
327 if (!dir_emit(ctx, "..", 2,
328 ceph_translate_ino(inode->i_sb, ino),
329 inode->i_mode >> 12))
330 return 0;
331 ctx->pos = 2;
332 }
333
334 /* can we use the dcache? */
335 spin_lock(&ci->i_ceph_lock);
336 if (ceph_test_mount_opt(fsc, DCACHE) &&
337 !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
338 ceph_snap(inode) != CEPH_SNAPDIR &&
339 __ceph_dir_is_complete_ordered(ci) &&
340 __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
341 int shared_gen = atomic_read(&ci->i_shared_gen);
342 spin_unlock(&ci->i_ceph_lock);
343 err = __dcache_readdir(file, ctx, shared_gen);
344 if (err != -EAGAIN)
345 return err;
346 } else {
347 spin_unlock(&ci->i_ceph_lock);
348 }
349
350 /* proceed with a normal readdir */
351 more:
352 /* do we have the correct frag content buffered? */
353 if (need_send_readdir(dfi, ctx->pos)) {
354 struct ceph_mds_request *req;
355 int op = ceph_snap(inode) == CEPH_SNAPDIR ?
356 CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
357
358 /* discard old result, if any */
359 if (dfi->last_readdir) {
360 ceph_mdsc_put_request(dfi->last_readdir);
361 dfi->last_readdir = NULL;
362 }
363
364 if (is_hash_order(ctx->pos)) {
365 /* fragtree isn't always accurate. choose frag
366 * based on previous reply when possible. */
367 if (frag == (unsigned)-1)
368 frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
369 NULL, NULL);
370 } else {
371 frag = fpos_frag(ctx->pos);
372 }
373
374 dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
375 ceph_vinop(inode), frag, dfi->last_name);
376 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
377 if (IS_ERR(req))
378 return PTR_ERR(req);
379 err = ceph_alloc_readdir_reply_buffer(req, inode);
380 if (err) {
381 ceph_mdsc_put_request(req);
382 return err;
383 }
384 /* hints to request -> mds selection code */
385 req->r_direct_mode = USE_AUTH_MDS;
386 if (op == CEPH_MDS_OP_READDIR) {
387 req->r_direct_hash = ceph_frag_value(frag);
388 __set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
389 req->r_inode_drop = CEPH_CAP_FILE_EXCL;
390 }
391 if (dfi->last_name) {
392 req->r_path2 = kstrdup(dfi->last_name, GFP_KERNEL);
393 if (!req->r_path2) {
394 ceph_mdsc_put_request(req);
395 return -ENOMEM;
396 }
397 } else if (is_hash_order(ctx->pos)) {
398 req->r_args.readdir.offset_hash =
399 cpu_to_le32(fpos_hash(ctx->pos));
400 }
401
402 req->r_dir_release_cnt = dfi->dir_release_count;
403 req->r_dir_ordered_cnt = dfi->dir_ordered_count;
404 req->r_readdir_cache_idx = dfi->readdir_cache_idx;
405 req->r_readdir_offset = dfi->next_offset;
406 req->r_args.readdir.frag = cpu_to_le32(frag);
407 req->r_args.readdir.flags =
408 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
409
410 req->r_inode = inode;
411 ihold(inode);
412 req->r_dentry = dget(file->f_path.dentry);
413 err = ceph_mdsc_do_request(mdsc, NULL, req);
414 if (err < 0) {
415 ceph_mdsc_put_request(req);
416 return err;
417 }
418 dout("readdir got and parsed readdir result=%d on "
419 "frag %x, end=%d, complete=%d, hash_order=%d\n",
420 err, frag,
421 (int)req->r_reply_info.dir_end,
422 (int)req->r_reply_info.dir_complete,
423 (int)req->r_reply_info.hash_order);
424
425 rinfo = &req->r_reply_info;
426 if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
427 frag = le32_to_cpu(rinfo->dir_dir->frag);
428 if (!rinfo->hash_order) {
429 dfi->next_offset = req->r_readdir_offset;
430 /* adjust ctx->pos to beginning of frag */
431 ctx->pos = ceph_make_fpos(frag,
432 dfi->next_offset,
433 false);
434 }
435 }
436
437 dfi->frag = frag;
438 dfi->last_readdir = req;
439
440 if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
441 dfi->readdir_cache_idx = req->r_readdir_cache_idx;
442 if (dfi->readdir_cache_idx < 0) {
443 /* preclude from marking dir ordered */
444 dfi->dir_ordered_count = 0;
445 } else if (ceph_frag_is_leftmost(frag) &&
446 dfi->next_offset == 2) {
447 /* note dir version at start of readdir so
448 * we can tell if any dentries get dropped */
449 dfi->dir_release_count = req->r_dir_release_cnt;
450 dfi->dir_ordered_count = req->r_dir_ordered_cnt;
451 }
452 } else {
453 dout("readdir !did_prepopulate\n");
454 /* disable readdir cache */
455 dfi->readdir_cache_idx = -1;
456 /* preclude from marking dir complete */
457 dfi->dir_release_count = 0;
458 }
459
460 /* note next offset and last dentry name */
461 if (rinfo->dir_nr > 0) {
462 struct ceph_mds_reply_dir_entry *rde =
463 rinfo->dir_entries + (rinfo->dir_nr-1);
464 unsigned next_offset = req->r_reply_info.dir_end ?
465 2 : (fpos_off(rde->offset) + 1);
466 err = note_last_dentry(dfi, rde->name, rde->name_len,
467 next_offset);
468 if (err)
469 return err;
470 } else if (req->r_reply_info.dir_end) {
471 dfi->next_offset = 2;
472 /* keep last name */
473 }
474 }
475
476 rinfo = &dfi->last_readdir->r_reply_info;
477 dout("readdir frag %x num %d pos %llx chunk first %llx\n",
478 dfi->frag, rinfo->dir_nr, ctx->pos,
479 rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
480
481 i = 0;
482 /* search start position */
483 if (rinfo->dir_nr > 0) {
484 int step, nr = rinfo->dir_nr;
485 while (nr > 0) {
486 step = nr >> 1;
487 if (rinfo->dir_entries[i + step].offset < ctx->pos) {
488 i += step + 1;
489 nr -= step + 1;
490 } else {
491 nr = step;
492 }
493 }
494 }
495 for (; i < rinfo->dir_nr; i++) {
496 struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
497 struct ceph_vino vino;
498 ino_t ino;
499 u32 ftype;
500
501 BUG_ON(rde->offset < ctx->pos);
502
503 ctx->pos = rde->offset;
504 dout("readdir (%d/%d) -> %llx '%.*s' %p\n",
505 i, rinfo->dir_nr, ctx->pos,
506 rde->name_len, rde->name, &rde->inode.in);
507
508 BUG_ON(!rde->inode.in);
509 ftype = le32_to_cpu(rde->inode.in->mode) >> 12;
510 vino.ino = le64_to_cpu(rde->inode.in->ino);
511 vino.snap = le64_to_cpu(rde->inode.in->snapid);
512 ino = ceph_vino_to_ino(vino);
513
514 if (!dir_emit(ctx, rde->name, rde->name_len,
515 ceph_translate_ino(inode->i_sb, ino), ftype)) {
516 dout("filldir stopping us...\n");
517 return 0;
518 }
519 ctx->pos++;
520 }
521
522 ceph_mdsc_put_request(dfi->last_readdir);
523 dfi->last_readdir = NULL;
524
525 if (dfi->next_offset > 2) {
526 frag = dfi->frag;
527 goto more;
528 }
529
530 /* more frags? */
531 if (!ceph_frag_is_rightmost(dfi->frag)) {
532 frag = ceph_frag_next(dfi->frag);
533 if (is_hash_order(ctx->pos)) {
534 loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
535 dfi->next_offset, true);
536 if (new_pos > ctx->pos)
537 ctx->pos = new_pos;
538 /* keep last_name */
539 } else {
540 ctx->pos = ceph_make_fpos(frag, dfi->next_offset,
541 false);
542 kfree(dfi->last_name);
543 dfi->last_name = NULL;
544 }
545 dout("readdir next frag is %x\n", frag);
546 goto more;
547 }
548 dfi->file_info.flags |= CEPH_F_ATEND;
549
550 /*
551 * if dir_release_count still matches the dir, no dentries
552 * were released during the whole readdir, and we should have
553 * the complete dir contents in our cache.
554 */
555 if (atomic64_read(&ci->i_release_count) ==
556 dfi->dir_release_count) {
557 spin_lock(&ci->i_ceph_lock);
558 if (dfi->dir_ordered_count ==
559 atomic64_read(&ci->i_ordered_count)) {
560 dout(" marking %p complete and ordered\n", inode);
561 /* use i_size to track number of entries in
562 * readdir cache */
563 BUG_ON(dfi->readdir_cache_idx < 0);
564 i_size_write(inode, dfi->readdir_cache_idx *
565 sizeof(struct dentry*));
566 } else {
567 dout(" marking %p complete\n", inode);
568 }
569 __ceph_dir_set_complete(ci, dfi->dir_release_count,
570 dfi->dir_ordered_count);
571 spin_unlock(&ci->i_ceph_lock);
572 }
573
574 dout("readdir %p file %p done.\n", inode, file);
575 return 0;
576 }
577
578 static void reset_readdir(struct ceph_dir_file_info *dfi)
579 {
580 if (dfi->last_readdir) {
581 ceph_mdsc_put_request(dfi->last_readdir);
582 dfi->last_readdir = NULL;
583 }
584 kfree(dfi->last_name);
585 dfi->last_name = NULL;
586 dfi->dir_release_count = 0;
587 dfi->readdir_cache_idx = -1;
588 dfi->next_offset = 2; /* compensate for . and .. */
589 dfi->file_info.flags &= ~CEPH_F_ATEND;
590 }
591
592 /*
593 * discard buffered readdir content on seekdir(0), or seek to new frag,
594 * or seek prior to current chunk
595 */
596 static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)
597 {
598 struct ceph_mds_reply_info_parsed *rinfo;
599 loff_t chunk_offset;
600 if (new_pos == 0)
601 return true;
602 if (is_hash_order(new_pos)) {
603 /* no need to reset last_name for a forward seek when
604 * dentries are sotred in hash order */
605 } else if (dfi->frag != fpos_frag(new_pos)) {
606 return true;
607 }
608 rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;
609 if (!rinfo || !rinfo->dir_nr)
610 return true;
611 chunk_offset = rinfo->dir_entries[0].offset;
612 return new_pos < chunk_offset ||
613 is_hash_order(new_pos) != is_hash_order(chunk_offset);
614 }
615
616 static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
617 {
618 struct ceph_dir_file_info *dfi = file->private_data;
619 struct inode *inode = file->f_mapping->host;
620 loff_t retval;
621
622 inode_lock(inode);
623 retval = -EINVAL;
624 switch (whence) {
625 case SEEK_CUR:
626 offset += file->f_pos;
627 case SEEK_SET:
628 break;
629 case SEEK_END:
630 retval = -EOPNOTSUPP;
631 default:
632 goto out;
633 }
634
635 if (offset >= 0) {
636 if (need_reset_readdir(dfi, offset)) {
637 dout("dir_llseek dropping %p content\n", file);
638 reset_readdir(dfi);
639 } else if (is_hash_order(offset) && offset > file->f_pos) {
640 /* for hash offset, we don't know if a forward seek
641 * is within same frag */
642 dfi->dir_release_count = 0;
643 dfi->readdir_cache_idx = -1;
644 }
645
646 if (offset != file->f_pos) {
647 file->f_pos = offset;
648 file->f_version = 0;
649 dfi->file_info.flags &= ~CEPH_F_ATEND;
650 }
651 retval = offset;
652 }
653 out:
654 inode_unlock(inode);
655 return retval;
656 }
657
658 /*
659 * Handle lookups for the hidden .snap directory.
660 */
661 int ceph_handle_snapdir(struct ceph_mds_request *req,
662 struct dentry *dentry, int err)
663 {
664 struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
665 struct inode *parent = d_inode(dentry->d_parent); /* we hold i_mutex */
666
667 /* .snap dir? */
668 if (err == -ENOENT &&
669 ceph_snap(parent) == CEPH_NOSNAP &&
670 strcmp(dentry->d_name.name,
671 fsc->mount_options->snapdir_name) == 0) {
672 struct inode *inode = ceph_get_snapdir(parent);
673 dout("ENOENT on snapdir %p '%pd', linking to snapdir %p\n",
674 dentry, dentry, inode);
675 BUG_ON(!d_unhashed(dentry));
676 d_add(dentry, inode);
677 err = 0;
678 }
679 return err;
680 }
681
682 /*
683 * Figure out final result of a lookup/open request.
684 *
685 * Mainly, make sure we return the final req->r_dentry (if it already
686 * existed) in place of the original VFS-provided dentry when they
687 * differ.
688 *
689 * Gracefully handle the case where the MDS replies with -ENOENT and
690 * no trace (which it may do, at its discretion, e.g., if it doesn't
691 * care to issue a lease on the negative dentry).
692 */
693 struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
694 struct dentry *dentry, int err)
695 {
696 if (err == -ENOENT) {
697 /* no trace? */
698 err = 0;
699 if (!req->r_reply_info.head->is_dentry) {
700 dout("ENOENT and no trace, dentry %p inode %p\n",
701 dentry, d_inode(dentry));
702 if (d_really_is_positive(dentry)) {
703 d_drop(dentry);
704 err = -ENOENT;
705 } else {
706 d_add(dentry, NULL);
707 }
708 }
709 }
710 if (err)
711 dentry = ERR_PTR(err);
712 else if (dentry != req->r_dentry)
713 dentry = dget(req->r_dentry); /* we got spliced */
714 else
715 dentry = NULL;
716 return dentry;
717 }
718
719 static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
720 {
721 return ceph_ino(inode) == CEPH_INO_ROOT &&
722 strncmp(dentry->d_name.name, ".ceph", 5) == 0;
723 }
724
725 /*
726 * Look up a single dir entry. If there is a lookup intent, inform
727 * the MDS so that it gets our 'caps wanted' value in a single op.
728 */
729 static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
730 unsigned int flags)
731 {
732 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
733 struct ceph_mds_client *mdsc = fsc->mdsc;
734 struct ceph_mds_request *req;
735 int op;
736 int mask;
737 int err;
738
739 dout("lookup %p dentry %p '%pd'\n",
740 dir, dentry, dentry);
741
742 if (dentry->d_name.len > NAME_MAX)
743 return ERR_PTR(-ENAMETOOLONG);
744
745 /* can we conclude ENOENT locally? */
746 if (d_really_is_negative(dentry)) {
747 struct ceph_inode_info *ci = ceph_inode(dir);
748 struct ceph_dentry_info *di = ceph_dentry(dentry);
749
750 spin_lock(&ci->i_ceph_lock);
751 dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags);
752 if (strncmp(dentry->d_name.name,
753 fsc->mount_options->snapdir_name,
754 dentry->d_name.len) &&
755 !is_root_ceph_dentry(dir, dentry) &&
756 ceph_test_mount_opt(fsc, DCACHE) &&
757 __ceph_dir_is_complete(ci) &&
758 (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
759 spin_unlock(&ci->i_ceph_lock);
760 dout(" dir %p complete, -ENOENT\n", dir);
761 d_add(dentry, NULL);
762 di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
763 return NULL;
764 }
765 spin_unlock(&ci->i_ceph_lock);
766 }
767
768 op = ceph_snap(dir) == CEPH_SNAPDIR ?
769 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
770 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
771 if (IS_ERR(req))
772 return ERR_CAST(req);
773 req->r_dentry = dget(dentry);
774 req->r_num_caps = 2;
775
776 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
777 if (ceph_security_xattr_wanted(dir))
778 mask |= CEPH_CAP_XATTR_SHARED;
779 req->r_args.getattr.mask = cpu_to_le32(mask);
780
781 req->r_parent = dir;
782 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
783 err = ceph_mdsc_do_request(mdsc, NULL, req);
784 err = ceph_handle_snapdir(req, dentry, err);
785 dentry = ceph_finish_lookup(req, dentry, err);
786 ceph_mdsc_put_request(req); /* will dput(dentry) */
787 dout("lookup result=%p\n", dentry);
788 return dentry;
789 }
790
791 /*
792 * If we do a create but get no trace back from the MDS, follow up with
793 * a lookup (the VFS expects us to link up the provided dentry).
794 */
795 int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
796 {
797 struct dentry *result = ceph_lookup(dir, dentry, 0);
798
799 if (result && !IS_ERR(result)) {
800 /*
801 * We created the item, then did a lookup, and found
802 * it was already linked to another inode we already
803 * had in our cache (and thus got spliced). To not
804 * confuse VFS (especially when inode is a directory),
805 * we don't link our dentry to that inode, return an
806 * error instead.
807 *
808 * This event should be rare and it happens only when
809 * we talk to old MDS. Recent MDS does not send traceless
810 * reply for request that creates new inode.
811 */
812 d_drop(result);
813 return -ESTALE;
814 }
815 return PTR_ERR(result);
816 }
817
818 static int ceph_mknod(struct inode *dir, struct dentry *dentry,
819 umode_t mode, dev_t rdev)
820 {
821 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
822 struct ceph_mds_client *mdsc = fsc->mdsc;
823 struct ceph_mds_request *req;
824 struct ceph_acls_info acls = {};
825 int err;
826
827 if (ceph_snap(dir) != CEPH_NOSNAP)
828 return -EROFS;
829
830 if (ceph_quota_is_max_files_exceeded(dir)) {
831 err = -EDQUOT;
832 goto out;
833 }
834
835 err = ceph_pre_init_acls(dir, &mode, &acls);
836 if (err < 0)
837 goto out;
838
839 dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
840 dir, dentry, mode, rdev);
841 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
842 if (IS_ERR(req)) {
843 err = PTR_ERR(req);
844 goto out;
845 }
846 req->r_dentry = dget(dentry);
847 req->r_num_caps = 2;
848 req->r_parent = dir;
849 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
850 req->r_args.mknod.mode = cpu_to_le32(mode);
851 req->r_args.mknod.rdev = cpu_to_le32(rdev);
852 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
853 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
854 if (acls.pagelist) {
855 req->r_pagelist = acls.pagelist;
856 acls.pagelist = NULL;
857 }
858 err = ceph_mdsc_do_request(mdsc, dir, req);
859 if (!err && !req->r_reply_info.head->is_dentry)
860 err = ceph_handle_notrace_create(dir, dentry);
861 ceph_mdsc_put_request(req);
862 out:
863 if (!err)
864 ceph_init_inode_acls(d_inode(dentry), &acls);
865 else
866 d_drop(dentry);
867 ceph_release_acls_info(&acls);
868 return err;
869 }
870
871 static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
872 bool excl)
873 {
874 return ceph_mknod(dir, dentry, mode, 0);
875 }
876
877 static int ceph_symlink(struct inode *dir, struct dentry *dentry,
878 const char *dest)
879 {
880 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
881 struct ceph_mds_client *mdsc = fsc->mdsc;
882 struct ceph_mds_request *req;
883 int err;
884
885 if (ceph_snap(dir) != CEPH_NOSNAP)
886 return -EROFS;
887
888 if (ceph_quota_is_max_files_exceeded(dir)) {
889 err = -EDQUOT;
890 goto out;
891 }
892
893 dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
894 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
895 if (IS_ERR(req)) {
896 err = PTR_ERR(req);
897 goto out;
898 }
899 req->r_path2 = kstrdup(dest, GFP_KERNEL);
900 if (!req->r_path2) {
901 err = -ENOMEM;
902 ceph_mdsc_put_request(req);
903 goto out;
904 }
905 req->r_parent = dir;
906 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
907 req->r_dentry = dget(dentry);
908 req->r_num_caps = 2;
909 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
910 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
911 err = ceph_mdsc_do_request(mdsc, dir, req);
912 if (!err && !req->r_reply_info.head->is_dentry)
913 err = ceph_handle_notrace_create(dir, dentry);
914 ceph_mdsc_put_request(req);
915 out:
916 if (err)
917 d_drop(dentry);
918 return err;
919 }
920
921 static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
922 {
923 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
924 struct ceph_mds_client *mdsc = fsc->mdsc;
925 struct ceph_mds_request *req;
926 struct ceph_acls_info acls = {};
927 int err = -EROFS;
928 int op;
929
930 if (ceph_snap(dir) == CEPH_SNAPDIR) {
931 /* mkdir .snap/foo is a MKSNAP */
932 op = CEPH_MDS_OP_MKSNAP;
933 dout("mksnap dir %p snap '%pd' dn %p\n", dir,
934 dentry, dentry);
935 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
936 dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
937 op = CEPH_MDS_OP_MKDIR;
938 } else {
939 goto out;
940 }
941
942 if (op == CEPH_MDS_OP_MKDIR &&
943 ceph_quota_is_max_files_exceeded(dir)) {
944 err = -EDQUOT;
945 goto out;
946 }
947
948 mode |= S_IFDIR;
949 err = ceph_pre_init_acls(dir, &mode, &acls);
950 if (err < 0)
951 goto out;
952
953 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
954 if (IS_ERR(req)) {
955 err = PTR_ERR(req);
956 goto out;
957 }
958
959 req->r_dentry = dget(dentry);
960 req->r_num_caps = 2;
961 req->r_parent = dir;
962 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
963 req->r_args.mkdir.mode = cpu_to_le32(mode);
964 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
965 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
966 if (acls.pagelist) {
967 req->r_pagelist = acls.pagelist;
968 acls.pagelist = NULL;
969 }
970 err = ceph_mdsc_do_request(mdsc, dir, req);
971 if (!err &&
972 !req->r_reply_info.head->is_target &&
973 !req->r_reply_info.head->is_dentry)
974 err = ceph_handle_notrace_create(dir, dentry);
975 ceph_mdsc_put_request(req);
976 out:
977 if (!err)
978 ceph_init_inode_acls(d_inode(dentry), &acls);
979 else
980 d_drop(dentry);
981 ceph_release_acls_info(&acls);
982 return err;
983 }
984
985 static int ceph_link(struct dentry *old_dentry, struct inode *dir,
986 struct dentry *dentry)
987 {
988 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
989 struct ceph_mds_client *mdsc = fsc->mdsc;
990 struct ceph_mds_request *req;
991 int err;
992
993 if (ceph_snap(dir) != CEPH_NOSNAP)
994 return -EROFS;
995
996 dout("link in dir %p old_dentry %p dentry %p\n", dir,
997 old_dentry, dentry);
998 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
999 if (IS_ERR(req)) {
1000 d_drop(dentry);
1001 return PTR_ERR(req);
1002 }
1003 req->r_dentry = dget(dentry);
1004 req->r_num_caps = 2;
1005 req->r_old_dentry = dget(old_dentry);
1006 req->r_parent = dir;
1007 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1008 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1009 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1010 /* release LINK_SHARED on source inode (mds will lock it) */
1011 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1012 err = ceph_mdsc_do_request(mdsc, dir, req);
1013 if (err) {
1014 d_drop(dentry);
1015 } else if (!req->r_reply_info.head->is_dentry) {
1016 ihold(d_inode(old_dentry));
1017 d_instantiate(dentry, d_inode(old_dentry));
1018 }
1019 ceph_mdsc_put_request(req);
1020 return err;
1021 }
1022
1023 /*
1024 * rmdir and unlink are differ only by the metadata op code
1025 */
1026 static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1027 {
1028 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
1029 struct ceph_mds_client *mdsc = fsc->mdsc;
1030 struct inode *inode = d_inode(dentry);
1031 struct ceph_mds_request *req;
1032 int err = -EROFS;
1033 int op;
1034
1035 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1036 /* rmdir .snap/foo is RMSNAP */
1037 dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry);
1038 op = CEPH_MDS_OP_RMSNAP;
1039 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1040 dout("unlink/rmdir dir %p dn %p inode %p\n",
1041 dir, dentry, inode);
1042 op = d_is_dir(dentry) ?
1043 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1044 } else
1045 goto out;
1046 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1047 if (IS_ERR(req)) {
1048 err = PTR_ERR(req);
1049 goto out;
1050 }
1051 req->r_dentry = dget(dentry);
1052 req->r_num_caps = 2;
1053 req->r_parent = dir;
1054 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1055 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1056 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1057 req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1058 err = ceph_mdsc_do_request(mdsc, dir, req);
1059 if (!err && !req->r_reply_info.head->is_dentry)
1060 d_delete(dentry);
1061 ceph_mdsc_put_request(req);
1062 out:
1063 return err;
1064 }
1065
1066 static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
1067 struct inode *new_dir, struct dentry *new_dentry,
1068 unsigned int flags)
1069 {
1070 struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
1071 struct ceph_mds_client *mdsc = fsc->mdsc;
1072 struct ceph_mds_request *req;
1073 int op = CEPH_MDS_OP_RENAME;
1074 int err;
1075
1076 if (flags)
1077 return -EINVAL;
1078
1079 if (ceph_snap(old_dir) != ceph_snap(new_dir))
1080 return -EXDEV;
1081 if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1082 if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1083 op = CEPH_MDS_OP_RENAMESNAP;
1084 else
1085 return -EROFS;
1086 }
1087 /* don't allow cross-quota renames */
1088 if ((old_dir != new_dir) &&
1089 (!ceph_quota_is_same_realm(old_dir, new_dir)))
1090 return -EXDEV;
1091
1092 dout("rename dir %p dentry %p to dir %p dentry %p\n",
1093 old_dir, old_dentry, new_dir, new_dentry);
1094 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1095 if (IS_ERR(req))
1096 return PTR_ERR(req);
1097 ihold(old_dir);
1098 req->r_dentry = dget(new_dentry);
1099 req->r_num_caps = 2;
1100 req->r_old_dentry = dget(old_dentry);
1101 req->r_old_dentry_dir = old_dir;
1102 req->r_parent = new_dir;
1103 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1104 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
1105 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1106 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1107 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1108 /* release LINK_RDCACHE on source inode (mds will lock it) */
1109 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1110 if (d_really_is_positive(new_dentry)) {
1111 req->r_inode_drop =
1112 ceph_drop_caps_for_unlink(d_inode(new_dentry));
1113 }
1114 err = ceph_mdsc_do_request(mdsc, old_dir, req);
1115 if (!err && !req->r_reply_info.head->is_dentry) {
1116 /*
1117 * Normally d_move() is done by fill_trace (called by
1118 * do_request, above). If there is no trace, we need
1119 * to do it here.
1120 */
1121 d_move(old_dentry, new_dentry);
1122 }
1123 ceph_mdsc_put_request(req);
1124 return err;
1125 }
1126
1127 /*
1128 * Ensure a dentry lease will no longer revalidate.
1129 */
1130 void ceph_invalidate_dentry_lease(struct dentry *dentry)
1131 {
1132 spin_lock(&dentry->d_lock);
1133 ceph_dentry(dentry)->time = jiffies;
1134 ceph_dentry(dentry)->lease_shared_gen = 0;
1135 spin_unlock(&dentry->d_lock);
1136 }
1137
1138 /*
1139 * Check if dentry lease is valid. If not, delete the lease. Try to
1140 * renew if the least is more than half up.
1141 */
1142 static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags,
1143 struct inode *dir)
1144 {
1145 struct ceph_dentry_info *di;
1146 struct ceph_mds_session *s;
1147 int valid = 0;
1148 u32 gen;
1149 unsigned long ttl;
1150 struct ceph_mds_session *session = NULL;
1151 u32 seq = 0;
1152
1153 spin_lock(&dentry->d_lock);
1154 di = ceph_dentry(dentry);
1155 if (di && di->lease_session) {
1156 s = di->lease_session;
1157 spin_lock(&s->s_gen_ttl_lock);
1158 gen = s->s_cap_gen;
1159 ttl = s->s_cap_ttl;
1160 spin_unlock(&s->s_gen_ttl_lock);
1161
1162 if (di->lease_gen == gen &&
1163 time_before(jiffies, di->time) &&
1164 time_before(jiffies, ttl)) {
1165 valid = 1;
1166 if (di->lease_renew_after &&
1167 time_after(jiffies, di->lease_renew_after)) {
1168 /*
1169 * We should renew. If we're in RCU walk mode
1170 * though, we can't do that so just return
1171 * -ECHILD.
1172 */
1173 if (flags & LOOKUP_RCU) {
1174 valid = -ECHILD;
1175 } else {
1176 session = ceph_get_mds_session(s);
1177 seq = di->lease_seq;
1178 di->lease_renew_after = 0;
1179 di->lease_renew_from = jiffies;
1180 }
1181 }
1182 }
1183 }
1184 spin_unlock(&dentry->d_lock);
1185
1186 if (session) {
1187 ceph_mdsc_lease_send_msg(session, dir, dentry,
1188 CEPH_MDS_LEASE_RENEW, seq);
1189 ceph_put_mds_session(session);
1190 }
1191 dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1192 return valid;
1193 }
1194
1195 /*
1196 * Check if directory-wide content lease/cap is valid.
1197 */
1198 static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
1199 {
1200 struct ceph_inode_info *ci = ceph_inode(dir);
1201 struct ceph_dentry_info *di = ceph_dentry(dentry);
1202 int valid = 0;
1203
1204 spin_lock(&ci->i_ceph_lock);
1205 if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen)
1206 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1207 spin_unlock(&ci->i_ceph_lock);
1208 dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
1209 dir, (unsigned)atomic_read(&ci->i_shared_gen),
1210 dentry, (unsigned)di->lease_shared_gen, valid);
1211 return valid;
1212 }
1213
1214 /*
1215 * Check if cached dentry can be trusted.
1216 */
1217 static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1218 {
1219 int valid = 0;
1220 struct dentry *parent;
1221 struct inode *dir;
1222
1223 if (flags & LOOKUP_RCU) {
1224 parent = READ_ONCE(dentry->d_parent);
1225 dir = d_inode_rcu(parent);
1226 if (!dir)
1227 return -ECHILD;
1228 } else {
1229 parent = dget_parent(dentry);
1230 dir = d_inode(parent);
1231 }
1232
1233 dout("d_revalidate %p '%pd' inode %p offset %lld\n", dentry,
1234 dentry, d_inode(dentry), ceph_dentry(dentry)->offset);
1235
1236 /* always trust cached snapped dentries, snapdir dentry */
1237 if (ceph_snap(dir) != CEPH_NOSNAP) {
1238 dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
1239 dentry, d_inode(dentry));
1240 valid = 1;
1241 } else if (d_really_is_positive(dentry) &&
1242 ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
1243 valid = 1;
1244 } else {
1245 valid = dentry_lease_is_valid(dentry, flags, dir);
1246 if (valid == -ECHILD)
1247 return valid;
1248 if (valid || dir_lease_is_valid(dir, dentry)) {
1249 if (d_really_is_positive(dentry))
1250 valid = ceph_is_any_caps(d_inode(dentry));
1251 else
1252 valid = 1;
1253 }
1254 }
1255
1256 if (!valid) {
1257 struct ceph_mds_client *mdsc =
1258 ceph_sb_to_client(dir->i_sb)->mdsc;
1259 struct ceph_mds_request *req;
1260 int op, err;
1261 u32 mask;
1262
1263 if (flags & LOOKUP_RCU)
1264 return -ECHILD;
1265
1266 op = ceph_snap(dir) == CEPH_SNAPDIR ?
1267 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
1268 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
1269 if (!IS_ERR(req)) {
1270 req->r_dentry = dget(dentry);
1271 req->r_num_caps = 2;
1272 req->r_parent = dir;
1273
1274 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
1275 if (ceph_security_xattr_wanted(dir))
1276 mask |= CEPH_CAP_XATTR_SHARED;
1277 req->r_args.getattr.mask = cpu_to_le32(mask);
1278
1279 err = ceph_mdsc_do_request(mdsc, NULL, req);
1280 switch (err) {
1281 case 0:
1282 if (d_really_is_positive(dentry) &&
1283 d_inode(dentry) == req->r_target_inode)
1284 valid = 1;
1285 break;
1286 case -ENOENT:
1287 if (d_really_is_negative(dentry))
1288 valid = 1;
1289 /* Fallthrough */
1290 default:
1291 break;
1292 }
1293 ceph_mdsc_put_request(req);
1294 dout("d_revalidate %p lookup result=%d\n",
1295 dentry, err);
1296 }
1297 }
1298
1299 dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1300 if (valid) {
1301 ceph_dentry_lru_touch(dentry);
1302 } else {
1303 ceph_dir_clear_complete(dir);
1304 }
1305
1306 if (!(flags & LOOKUP_RCU))
1307 dput(parent);
1308 return valid;
1309 }
1310
1311 /*
1312 * Release our ceph_dentry_info.
1313 */
1314 static void ceph_d_release(struct dentry *dentry)
1315 {
1316 struct ceph_dentry_info *di = ceph_dentry(dentry);
1317
1318 dout("d_release %p\n", dentry);
1319 ceph_dentry_lru_del(dentry);
1320
1321 spin_lock(&dentry->d_lock);
1322 dentry->d_fsdata = NULL;
1323 spin_unlock(&dentry->d_lock);
1324
1325 if (di->lease_session)
1326 ceph_put_mds_session(di->lease_session);
1327 kmem_cache_free(ceph_dentry_cachep, di);
1328 }
1329
1330 /*
1331 * When the VFS prunes a dentry from the cache, we need to clear the
1332 * complete flag on the parent directory.
1333 *
1334 * Called under dentry->d_lock.
1335 */
1336 static void ceph_d_prune(struct dentry *dentry)
1337 {
1338 struct ceph_inode_info *dir_ci;
1339 struct ceph_dentry_info *di;
1340
1341 dout("ceph_d_prune %pd %p\n", dentry, dentry);
1342
1343 /* do we have a valid parent? */
1344 if (IS_ROOT(dentry))
1345 return;
1346
1347 /* we hold d_lock, so d_parent is stable */
1348 dir_ci = ceph_inode(d_inode(dentry->d_parent));
1349 if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
1350 return;
1351
1352 /* who calls d_delete() should also disable dcache readdir */
1353 if (d_really_is_negative(dentry))
1354 return;
1355
1356 /* d_fsdata does not get cleared until d_release */
1357 if (!d_unhashed(dentry)) {
1358 __ceph_dir_clear_complete(dir_ci);
1359 return;
1360 }
1361
1362 /* Disable dcache readdir just in case that someone called d_drop()
1363 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
1364 * properly (dcache readdir is still enabled) */
1365 di = ceph_dentry(dentry);
1366 if (di->offset > 0 &&
1367 di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
1368 __ceph_dir_clear_ordered(dir_ci);
1369 }
1370
1371 /*
1372 * read() on a dir. This weird interface hack only works if mounted
1373 * with '-o dirstat'.
1374 */
1375 static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1376 loff_t *ppos)
1377 {
1378 struct ceph_dir_file_info *dfi = file->private_data;
1379 struct inode *inode = file_inode(file);
1380 struct ceph_inode_info *ci = ceph_inode(inode);
1381 int left;
1382 const int bufsize = 1024;
1383
1384 if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1385 return -EISDIR;
1386
1387 if (!dfi->dir_info) {
1388 dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
1389 if (!dfi->dir_info)
1390 return -ENOMEM;
1391 dfi->dir_info_len =
1392 snprintf(dfi->dir_info, bufsize,
1393 "entries: %20lld\n"
1394 " files: %20lld\n"
1395 " subdirs: %20lld\n"
1396 "rentries: %20lld\n"
1397 " rfiles: %20lld\n"
1398 " rsubdirs: %20lld\n"
1399 "rbytes: %20lld\n"
1400 "rctime: %10lld.%09ld\n",
1401 ci->i_files + ci->i_subdirs,
1402 ci->i_files,
1403 ci->i_subdirs,
1404 ci->i_rfiles + ci->i_rsubdirs,
1405 ci->i_rfiles,
1406 ci->i_rsubdirs,
1407 ci->i_rbytes,
1408 ci->i_rctime.tv_sec,
1409 ci->i_rctime.tv_nsec);
1410 }
1411
1412 if (*ppos >= dfi->dir_info_len)
1413 return 0;
1414 size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
1415 left = copy_to_user(buf, dfi->dir_info + *ppos, size);
1416 if (left == size)
1417 return -EFAULT;
1418 *ppos += (size - left);
1419 return size - left;
1420 }
1421
1422 /*
1423 * We maintain a private dentry LRU.
1424 *
1425 * FIXME: this needs to be changed to a per-mds lru to be useful.
1426 */
1427 void ceph_dentry_lru_add(struct dentry *dn)
1428 {
1429 struct ceph_dentry_info *di = ceph_dentry(dn);
1430 struct ceph_mds_client *mdsc;
1431
1432 dout("dentry_lru_add %p %p '%pd'\n", di, dn, dn);
1433 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1434 spin_lock(&mdsc->dentry_lru_lock);
1435 list_add_tail(&di->lru, &mdsc->dentry_lru);
1436 mdsc->num_dentry++;
1437 spin_unlock(&mdsc->dentry_lru_lock);
1438 }
1439
1440 void ceph_dentry_lru_touch(struct dentry *dn)
1441 {
1442 struct ceph_dentry_info *di = ceph_dentry(dn);
1443 struct ceph_mds_client *mdsc;
1444
1445 dout("dentry_lru_touch %p %p '%pd' (offset %lld)\n", di, dn, dn,
1446 di->offset);
1447 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1448 spin_lock(&mdsc->dentry_lru_lock);
1449 list_move_tail(&di->lru, &mdsc->dentry_lru);
1450 spin_unlock(&mdsc->dentry_lru_lock);
1451 }
1452
1453 void ceph_dentry_lru_del(struct dentry *dn)
1454 {
1455 struct ceph_dentry_info *di = ceph_dentry(dn);
1456 struct ceph_mds_client *mdsc;
1457
1458 dout("dentry_lru_del %p %p '%pd'\n", di, dn, dn);
1459 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1460 spin_lock(&mdsc->dentry_lru_lock);
1461 list_del_init(&di->lru);
1462 mdsc->num_dentry--;
1463 spin_unlock(&mdsc->dentry_lru_lock);
1464 }
1465
1466 /*
1467 * Return name hash for a given dentry. This is dependent on
1468 * the parent directory's hash function.
1469 */
1470 unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1471 {
1472 struct ceph_inode_info *dci = ceph_inode(dir);
1473 unsigned hash;
1474
1475 switch (dci->i_dir_layout.dl_dir_hash) {
1476 case 0: /* for backward compat */
1477 case CEPH_STR_HASH_LINUX:
1478 return dn->d_name.hash;
1479
1480 default:
1481 spin_lock(&dn->d_lock);
1482 hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
1483 dn->d_name.name, dn->d_name.len);
1484 spin_unlock(&dn->d_lock);
1485 return hash;
1486 }
1487 }
1488
1489 const struct file_operations ceph_dir_fops = {
1490 .read = ceph_read_dir,
1491 .iterate = ceph_readdir,
1492 .llseek = ceph_dir_llseek,
1493 .open = ceph_open,
1494 .release = ceph_release,
1495 .unlocked_ioctl = ceph_ioctl,
1496 .fsync = ceph_fsync,
1497 .lock = ceph_lock,
1498 .flock = ceph_flock,
1499 };
1500
1501 const struct file_operations ceph_snapdir_fops = {
1502 .iterate = ceph_readdir,
1503 .llseek = ceph_dir_llseek,
1504 .open = ceph_open,
1505 .release = ceph_release,
1506 };
1507
1508 const struct inode_operations ceph_dir_iops = {
1509 .lookup = ceph_lookup,
1510 .permission = ceph_permission,
1511 .getattr = ceph_getattr,
1512 .setattr = ceph_setattr,
1513 .listxattr = ceph_listxattr,
1514 .get_acl = ceph_get_acl,
1515 .set_acl = ceph_set_acl,
1516 .mknod = ceph_mknod,
1517 .symlink = ceph_symlink,
1518 .mkdir = ceph_mkdir,
1519 .link = ceph_link,
1520 .unlink = ceph_unlink,
1521 .rmdir = ceph_unlink,
1522 .rename = ceph_rename,
1523 .create = ceph_create,
1524 .atomic_open = ceph_atomic_open,
1525 };
1526
1527 const struct inode_operations ceph_snapdir_iops = {
1528 .lookup = ceph_lookup,
1529 .permission = ceph_permission,
1530 .getattr = ceph_getattr,
1531 .mkdir = ceph_mkdir,
1532 .rmdir = ceph_unlink,
1533 .rename = ceph_rename,
1534 };
1535
1536 const struct dentry_operations ceph_dentry_ops = {
1537 .d_revalidate = ceph_d_revalidate,
1538 .d_release = ceph_d_release,
1539 .d_prune = ceph_d_prune,
1540 .d_init = ceph_d_init,
1541 };
Linux with added FPC-III support