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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / fs / ceph / dir.c
blobf1d9c6cc0491d7f9f33e4073db9785afac669cc8
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/ceph/ceph_debug.h>
3
4 #include <linux/spinlock.h>
5 #include <linux/fs_struct.h>
6 #include <linux/namei.h>
7 #include <linux/slab.h>
8 #include <linux/sched.h>
9 #include <linux/xattr.h>
10
11 #include "super.h"
12 #include "mds_client.h"
13
14 /*
15 * Directory operations: readdir, lookup, create, link, unlink,
16 * rename, etc.
17 */
18
19 /*
20 * Ceph MDS operations are specified in terms of a base ino and
21 * relative path. Thus, the client can specify an operation on a
22 * specific inode (e.g., a getattr due to fstat(2)), or as a path
23 * relative to, say, the root directory.
24 *
25 * Normally, we limit ourselves to strict inode ops (no path component)
26 * or dentry operations (a single path component relative to an ino). The
27 * exception to this is open_root_dentry(), which will open the mount
28 * point by name.
29 */
30
31 const struct dentry_operations ceph_dentry_ops;
32
33 /*
34 * Initialize ceph dentry state.
35 */
36 static int ceph_d_init(struct dentry *dentry)
37 {
38 struct ceph_dentry_info *di;
39
40 di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
41 if (!di)
42 return -ENOMEM; /* oh well */
43
44 di->dentry = dentry;
45 di->lease_session = NULL;
46 di->time = jiffies;
47 dentry->d_fsdata = di;
48 ceph_dentry_lru_add(dentry);
49 return 0;
50 }
51
52 /*
53 * for f_pos for readdir:
54 * - hash order:
55 * (0xff << 52) | ((24 bits hash) << 28) |
56 * (the nth entry has hash collision);
57 * - frag+name order;
58 * ((frag value) << 28) | (the nth entry in frag);
59 */
60 #define OFFSET_BITS 28
61 #define OFFSET_MASK ((1 << OFFSET_BITS) - 1)
62 #define HASH_ORDER (0xffull << (OFFSET_BITS + 24))
63 loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
64 {
65 loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
66 if (hash_order)
67 fpos |= HASH_ORDER;
68 return fpos;
69 }
70
71 static bool is_hash_order(loff_t p)
72 {
73 return (p & HASH_ORDER) == HASH_ORDER;
74 }
75
76 static unsigned fpos_frag(loff_t p)
77 {
78 return p >> OFFSET_BITS;
79 }
80
81 static unsigned fpos_hash(loff_t p)
82 {
83 return ceph_frag_value(fpos_frag(p));
84 }
85
86 static unsigned fpos_off(loff_t p)
87 {
88 return p & OFFSET_MASK;
89 }
90
91 static int fpos_cmp(loff_t l, loff_t r)
92 {
93 int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
94 if (v)
95 return v;
96 return (int)(fpos_off(l) - fpos_off(r));
97 }
98
99 /*
100 * make note of the last dentry we read, so we can
101 * continue at the same lexicographical point,
102 * regardless of what dir changes take place on the
103 * server.
104 */
105 static int note_last_dentry(struct ceph_file_info *fi, const char *name,
106 int len, unsigned next_offset)
107 {
108 char *buf = kmalloc(len+1, GFP_KERNEL);
109 if (!buf)
110 return -ENOMEM;
111 kfree(fi->last_name);
112 fi->last_name = buf;
113 memcpy(fi->last_name, name, len);
114 fi->last_name[len] = 0;
115 fi->next_offset = next_offset;
116 dout("note_last_dentry '%s'\n", fi->last_name);
117 return 0;
118 }
119
120
121 static struct dentry *
122 __dcache_find_get_entry(struct dentry *parent, u64 idx,
123 struct ceph_readdir_cache_control *cache_ctl)
124 {
125 struct inode *dir = d_inode(parent);
126 struct dentry *dentry;
127 unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
128 loff_t ptr_pos = idx * sizeof(struct dentry *);
129 pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
130
131 if (ptr_pos >= i_size_read(dir))
132 return NULL;
133
134 if (!cache_ctl->page || ptr_pgoff != page_index(cache_ctl->page)) {
135 ceph_readdir_cache_release(cache_ctl);
136 cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
137 if (!cache_ctl->page) {
138 dout(" page %lu not found\n", ptr_pgoff);
139 return ERR_PTR(-EAGAIN);
140 }
141 /* reading/filling the cache are serialized by
142 i_mutex, no need to use page lock */
143 unlock_page(cache_ctl->page);
144 cache_ctl->dentries = kmap(cache_ctl->page);
145 }
146
147 cache_ctl->index = idx & idx_mask;
148
149 rcu_read_lock();
150 spin_lock(&parent->d_lock);
151 /* check i_size again here, because empty directory can be
152 * marked as complete while not holding the i_mutex. */
153 if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))
154 dentry = cache_ctl->dentries[cache_ctl->index];
155 else
156 dentry = NULL;
157 spin_unlock(&parent->d_lock);
158 if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
159 dentry = NULL;
160 rcu_read_unlock();
161 return dentry ? : ERR_PTR(-EAGAIN);
162 }
163
164 /*
165 * When possible, we try to satisfy a readdir by peeking at the
166 * dcache. We make this work by carefully ordering dentries on
167 * d_child when we initially get results back from the MDS, and
168 * falling back to a "normal" sync readdir if any dentries in the dir
169 * are dropped.
170 *
171 * Complete dir indicates that we have all dentries in the dir. It is
172 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
173 * the MDS if/when the directory is modified).
174 */
175 static int __dcache_readdir(struct file *file, struct dir_context *ctx,
176 int shared_gen)
177 {
178 struct ceph_file_info *fi = file->private_data;
179 struct dentry *parent = file->f_path.dentry;
180 struct inode *dir = d_inode(parent);
181 struct dentry *dentry, *last = NULL;
182 struct ceph_dentry_info *di;
183 struct ceph_readdir_cache_control cache_ctl = {};
184 u64 idx = 0;
185 int err = 0;
186
187 dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos);
188
189 /* search start position */
190 if (ctx->pos > 2) {
191 u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
192 while (count > 0) {
193 u64 step = count >> 1;
194 dentry = __dcache_find_get_entry(parent, idx + step,
195 &cache_ctl);
196 if (!dentry) {
197 /* use linar search */
198 idx = 0;
199 break;
200 }
201 if (IS_ERR(dentry)) {
202 err = PTR_ERR(dentry);
203 goto out;
204 }
205 di = ceph_dentry(dentry);
206 spin_lock(&dentry->d_lock);
207 if (fpos_cmp(di->offset, ctx->pos) < 0) {
208 idx += step + 1;
209 count -= step + 1;
210 } else {
211 count = step;
212 }
213 spin_unlock(&dentry->d_lock);
214 dput(dentry);
215 }
216
217 dout("__dcache_readdir %p cache idx %llu\n", dir, idx);
218 }
219
220
221 for (;;) {
222 bool emit_dentry = false;
223 dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
224 if (!dentry) {
225 fi->flags |= CEPH_F_ATEND;
226 err = 0;
227 break;
228 }
229 if (IS_ERR(dentry)) {
230 err = PTR_ERR(dentry);
231 goto out;
232 }
233
234 spin_lock(&dentry->d_lock);
235 di = ceph_dentry(dentry);
236 if (d_unhashed(dentry) ||
237 d_really_is_negative(dentry) ||
238 di->lease_shared_gen != shared_gen) {
239 spin_unlock(&dentry->d_lock);
240 dput(dentry);
241 err = -EAGAIN;
242 goto out;
243 }
244 if (fpos_cmp(ctx->pos, di->offset) <= 0) {
245 emit_dentry = true;
246 }
247 spin_unlock(&dentry->d_lock);
248
249 if (emit_dentry) {
250 dout(" %llx dentry %p %pd %p\n", di->offset,
251 dentry, dentry, d_inode(dentry));
252 ctx->pos = di->offset;
253 if (!dir_emit(ctx, dentry->d_name.name,
254 dentry->d_name.len,
255 ceph_translate_ino(dentry->d_sb,
256 d_inode(dentry)->i_ino),
257 d_inode(dentry)->i_mode >> 12)) {
258 dput(dentry);
259 err = 0;
260 break;
261 }
262 ctx->pos++;
263
264 if (last)
265 dput(last);
266 last = dentry;
267 } else {
268 dput(dentry);
269 }
270 }
271 out:
272 ceph_readdir_cache_release(&cache_ctl);
273 if (last) {
274 int ret;
275 di = ceph_dentry(last);
276 ret = note_last_dentry(fi, last->d_name.name, last->d_name.len,
277 fpos_off(di->offset) + 1);
278 if (ret < 0)
279 err = ret;
280 dput(last);
281 /* last_name no longer match cache index */
282 if (fi->readdir_cache_idx >= 0) {
283 fi->readdir_cache_idx = -1;
284 fi->dir_release_count = 0;
285 }
286 }
287 return err;
288 }
289
290 static bool need_send_readdir(struct ceph_file_info *fi, loff_t pos)
291 {
292 if (!fi->last_readdir)
293 return true;
294 if (is_hash_order(pos))
295 return !ceph_frag_contains_value(fi->frag, fpos_hash(pos));
296 else
297 return fi->frag != fpos_frag(pos);
298 }
299
300 static int ceph_readdir(struct file *file, struct dir_context *ctx)
301 {
302 struct ceph_file_info *fi = file->private_data;
303 struct inode *inode = file_inode(file);
304 struct ceph_inode_info *ci = ceph_inode(inode);
305 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
306 struct ceph_mds_client *mdsc = fsc->mdsc;
307 int i;
308 int err;
309 unsigned frag = -1;
310 struct ceph_mds_reply_info_parsed *rinfo;
311
312 dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
313 if (fi->flags & CEPH_F_ATEND)
314 return 0;
315
316 /* always start with . and .. */
317 if (ctx->pos == 0) {
318 dout("readdir off 0 -> '.'\n");
319 if (!dir_emit(ctx, ".", 1,
320 ceph_translate_ino(inode->i_sb, inode->i_ino),
321 inode->i_mode >> 12))
322 return 0;
323 ctx->pos = 1;
324 }
325 if (ctx->pos == 1) {
326 ino_t ino = parent_ino(file->f_path.dentry);
327 dout("readdir off 1 -> '..'\n");
328 if (!dir_emit(ctx, "..", 2,
329 ceph_translate_ino(inode->i_sb, ino),
330 inode->i_mode >> 12))
331 return 0;
332 ctx->pos = 2;
333 }
334
335 /* can we use the dcache? */
336 spin_lock(&ci->i_ceph_lock);
337 if (ceph_test_mount_opt(fsc, DCACHE) &&
338 !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
339 ceph_snap(inode) != CEPH_SNAPDIR &&
340 __ceph_dir_is_complete_ordered(ci) &&
341 __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
342 int shared_gen = atomic_read(&ci->i_shared_gen);
343 spin_unlock(&ci->i_ceph_lock);
344 err = __dcache_readdir(file, ctx, shared_gen);
345 if (err != -EAGAIN)
346 return err;
347 } else {
348 spin_unlock(&ci->i_ceph_lock);
349 }
350
351 /* proceed with a normal readdir */
352 more:
353 /* do we have the correct frag content buffered? */
354 if (need_send_readdir(fi, ctx->pos)) {
355 struct ceph_mds_request *req;
356 int op = ceph_snap(inode) == CEPH_SNAPDIR ?
357 CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
358
359 /* discard old result, if any */
360 if (fi->last_readdir) {
361 ceph_mdsc_put_request(fi->last_readdir);
362 fi->last_readdir = NULL;
363 }
364
365 if (is_hash_order(ctx->pos)) {
366 /* fragtree isn't always accurate. choose frag
367 * based on previous reply when possible. */
368 if (frag == (unsigned)-1)
369 frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
370 NULL, NULL);
371 } else {
372 frag = fpos_frag(ctx->pos);
373 }
374
375 dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
376 ceph_vinop(inode), frag, fi->last_name);
377 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
378 if (IS_ERR(req))
379 return PTR_ERR(req);
380 err = ceph_alloc_readdir_reply_buffer(req, inode);
381 if (err) {
382 ceph_mdsc_put_request(req);
383 return err;
384 }
385 /* hints to request -> mds selection code */
386 req->r_direct_mode = USE_AUTH_MDS;
387 if (op == CEPH_MDS_OP_READDIR) {
388 req->r_direct_hash = ceph_frag_value(frag);
389 __set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
390 req->r_inode_drop = CEPH_CAP_FILE_EXCL;
391 }
392 if (fi->last_name) {
393 req->r_path2 = kstrdup(fi->last_name, GFP_KERNEL);
394 if (!req->r_path2) {
395 ceph_mdsc_put_request(req);
396 return -ENOMEM;
397 }
398 } else if (is_hash_order(ctx->pos)) {
399 req->r_args.readdir.offset_hash =
400 cpu_to_le32(fpos_hash(ctx->pos));
401 }
402
403 req->r_dir_release_cnt = fi->dir_release_count;
404 req->r_dir_ordered_cnt = fi->dir_ordered_count;
405 req->r_readdir_cache_idx = fi->readdir_cache_idx;
406 req->r_readdir_offset = fi->next_offset;
407 req->r_args.readdir.frag = cpu_to_le32(frag);
408 req->r_args.readdir.flags =
409 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
410
411 req->r_inode = inode;
412 ihold(inode);
413 req->r_dentry = dget(file->f_path.dentry);
414 err = ceph_mdsc_do_request(mdsc, NULL, req);
415 if (err < 0) {
416 ceph_mdsc_put_request(req);
417 return err;
418 }
419 dout("readdir got and parsed readdir result=%d on "
420 "frag %x, end=%d, complete=%d, hash_order=%d\n",
421 err, frag,
422 (int)req->r_reply_info.dir_end,
423 (int)req->r_reply_info.dir_complete,
424 (int)req->r_reply_info.hash_order);
425
426 rinfo = &req->r_reply_info;
427 if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
428 frag = le32_to_cpu(rinfo->dir_dir->frag);
429 if (!rinfo->hash_order) {
430 fi->next_offset = req->r_readdir_offset;
431 /* adjust ctx->pos to beginning of frag */
432 ctx->pos = ceph_make_fpos(frag,
433 fi->next_offset,
434 false);
435 }
436 }
437
438 fi->frag = frag;
439 fi->last_readdir = req;
440
441 if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
442 fi->readdir_cache_idx = req->r_readdir_cache_idx;
443 if (fi->readdir_cache_idx < 0) {
444 /* preclude from marking dir ordered */
445 fi->dir_ordered_count = 0;
446 } else if (ceph_frag_is_leftmost(frag) &&
447 fi->next_offset == 2) {
448 /* note dir version at start of readdir so
449 * we can tell if any dentries get dropped */
450 fi->dir_release_count = req->r_dir_release_cnt;
451 fi->dir_ordered_count = req->r_dir_ordered_cnt;
452 }
453 } else {
454 dout("readdir !did_prepopulate");
455 /* disable readdir cache */
456 fi->readdir_cache_idx = -1;
457 /* preclude from marking dir complete */
458 fi->dir_release_count = 0;
459 }
460
461 /* note next offset and last dentry name */
462 if (rinfo->dir_nr > 0) {
463 struct ceph_mds_reply_dir_entry *rde =
464 rinfo->dir_entries + (rinfo->dir_nr-1);
465 unsigned next_offset = req->r_reply_info.dir_end ?
466 2 : (fpos_off(rde->offset) + 1);
467 err = note_last_dentry(fi, rde->name, rde->name_len,
468 next_offset);
469 if (err)
470 return err;
471 } else if (req->r_reply_info.dir_end) {
472 fi->next_offset = 2;
473 /* keep last name */
474 }
475 }
476
477 rinfo = &fi->last_readdir->r_reply_info;
478 dout("readdir frag %x num %d pos %llx chunk first %llx\n",
479 fi->frag, rinfo->dir_nr, ctx->pos,
480 rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
481
482 i = 0;
483 /* search start position */
484 if (rinfo->dir_nr > 0) {
485 int step, nr = rinfo->dir_nr;
486 while (nr > 0) {
487 step = nr >> 1;
488 if (rinfo->dir_entries[i + step].offset < ctx->pos) {
489 i += step + 1;
490 nr -= step + 1;
491 } else {
492 nr = step;
493 }
494 }
495 }
496 for (; i < rinfo->dir_nr; i++) {
497 struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
498 struct ceph_vino vino;
499 ino_t ino;
500 u32 ftype;
501
502 BUG_ON(rde->offset < ctx->pos);
503
504 ctx->pos = rde->offset;
505 dout("readdir (%d/%d) -> %llx '%.*s' %p\n",
506 i, rinfo->dir_nr, ctx->pos,
507 rde->name_len, rde->name, &rde->inode.in);
508
509 BUG_ON(!rde->inode.in);
510 ftype = le32_to_cpu(rde->inode.in->mode) >> 12;
511 vino.ino = le64_to_cpu(rde->inode.in->ino);
512 vino.snap = le64_to_cpu(rde->inode.in->snapid);
513 ino = ceph_vino_to_ino(vino);
514
515 if (!dir_emit(ctx, rde->name, rde->name_len,
516 ceph_translate_ino(inode->i_sb, ino), ftype)) {
517 dout("filldir stopping us...\n");
518 return 0;
519 }
520 ctx->pos++;
521 }
522
523 ceph_mdsc_put_request(fi->last_readdir);
524 fi->last_readdir = NULL;
525
526 if (fi->next_offset > 2) {
527 frag = fi->frag;
528 goto more;
529 }
530
531 /* more frags? */
532 if (!ceph_frag_is_rightmost(fi->frag)) {
533 frag = ceph_frag_next(fi->frag);
534 if (is_hash_order(ctx->pos)) {
535 loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
536 fi->next_offset, true);
537 if (new_pos > ctx->pos)
538 ctx->pos = new_pos;
539 /* keep last_name */
540 } else {
541 ctx->pos = ceph_make_fpos(frag, fi->next_offset, false);
542 kfree(fi->last_name);
543 fi->last_name = NULL;
544 }
545 dout("readdir next frag is %x\n", frag);
546 goto more;
547 }
548 fi->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) == fi->dir_release_count) {
556 spin_lock(&ci->i_ceph_lock);
557 if (fi->dir_ordered_count == atomic64_read(&ci->i_ordered_count)) {
558 dout(" marking %p complete and ordered\n", inode);
559 /* use i_size to track number of entries in
560 * readdir cache */
561 BUG_ON(fi->readdir_cache_idx < 0);
562 i_size_write(inode, fi->readdir_cache_idx *
563 sizeof(struct dentry*));
564 } else {
565 dout(" marking %p complete\n", inode);
566 }
567 __ceph_dir_set_complete(ci, fi->dir_release_count,
568 fi->dir_ordered_count);
569 spin_unlock(&ci->i_ceph_lock);
570 }
571
572 dout("readdir %p file %p done.\n", inode, file);
573 return 0;
574 }
575
576 static void reset_readdir(struct ceph_file_info *fi)
577 {
578 if (fi->last_readdir) {
579 ceph_mdsc_put_request(fi->last_readdir);
580 fi->last_readdir = NULL;
581 }
582 kfree(fi->last_name);
583 fi->last_name = NULL;
584 fi->dir_release_count = 0;
585 fi->readdir_cache_idx = -1;
586 fi->next_offset = 2; /* compensate for . and .. */
587 fi->flags &= ~CEPH_F_ATEND;
588 }
589
590 /*
591 * discard buffered readdir content on seekdir(0), or seek to new frag,
592 * or seek prior to current chunk
593 */
594 static bool need_reset_readdir(struct ceph_file_info *fi, loff_t new_pos)
595 {
596 struct ceph_mds_reply_info_parsed *rinfo;
597 loff_t chunk_offset;
598 if (new_pos == 0)
599 return true;
600 if (is_hash_order(new_pos)) {
601 /* no need to reset last_name for a forward seek when
602 * dentries are sotred in hash order */
603 } else if (fi->frag != fpos_frag(new_pos)) {
604 return true;
605 }
606 rinfo = fi->last_readdir ? &fi->last_readdir->r_reply_info : NULL;
607 if (!rinfo || !rinfo->dir_nr)
608 return true;
609 chunk_offset = rinfo->dir_entries[0].offset;
610 return new_pos < chunk_offset ||
611 is_hash_order(new_pos) != is_hash_order(chunk_offset);
612 }
613
614 static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
615 {
616 struct ceph_file_info *fi = file->private_data;
617 struct inode *inode = file->f_mapping->host;
618 loff_t retval;
619
620 inode_lock(inode);
621 retval = -EINVAL;
622 switch (whence) {
623 case SEEK_CUR:
624 offset += file->f_pos;
625 case SEEK_SET:
626 break;
627 case SEEK_END:
628 retval = -EOPNOTSUPP;
629 default:
630 goto out;
631 }
632
633 if (offset >= 0) {
634 if (need_reset_readdir(fi, offset)) {
635 dout("dir_llseek dropping %p content\n", file);
636 reset_readdir(fi);
637 } else if (is_hash_order(offset) && offset > file->f_pos) {
638 /* for hash offset, we don't know if a forward seek
639 * is within same frag */
640 fi->dir_release_count = 0;
641 fi->readdir_cache_idx = -1;
642 }
643
644 if (offset != file->f_pos) {
645 file->f_pos = offset;
646 file->f_version = 0;
647 fi->flags &= ~CEPH_F_ATEND;
648 }
649 retval = offset;
650 }
651 out:
652 inode_unlock(inode);
653 return retval;
654 }
655
656 /*
657 * Handle lookups for the hidden .snap directory.
658 */
659 int ceph_handle_snapdir(struct ceph_mds_request *req,
660 struct dentry *dentry, int err)
661 {
662 struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
663 struct inode *parent = d_inode(dentry->d_parent); /* we hold i_mutex */
664
665 /* .snap dir? */
666 if (err == -ENOENT &&
667 ceph_snap(parent) == CEPH_NOSNAP &&
668 strcmp(dentry->d_name.name,
669 fsc->mount_options->snapdir_name) == 0) {
670 struct inode *inode = ceph_get_snapdir(parent);
671 dout("ENOENT on snapdir %p '%pd', linking to snapdir %p\n",
672 dentry, dentry, inode);
673 BUG_ON(!d_unhashed(dentry));
674 d_add(dentry, inode);
675 err = 0;
676 }
677 return err;
678 }
679
680 /*
681 * Figure out final result of a lookup/open request.
682 *
683 * Mainly, make sure we return the final req->r_dentry (if it already
684 * existed) in place of the original VFS-provided dentry when they
685 * differ.
686 *
687 * Gracefully handle the case where the MDS replies with -ENOENT and
688 * no trace (which it may do, at its discretion, e.g., if it doesn't
689 * care to issue a lease on the negative dentry).
690 */
691 struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
692 struct dentry *dentry, int err)
693 {
694 if (err == -ENOENT) {
695 /* no trace? */
696 err = 0;
697 if (!req->r_reply_info.head->is_dentry) {
698 dout("ENOENT and no trace, dentry %p inode %p\n",
699 dentry, d_inode(dentry));
700 if (d_really_is_positive(dentry)) {
701 d_drop(dentry);
702 err = -ENOENT;
703 } else {
704 d_add(dentry, NULL);
705 }
706 }
707 }
708 if (err)
709 dentry = ERR_PTR(err);
710 else if (dentry != req->r_dentry)
711 dentry = dget(req->r_dentry); /* we got spliced */
712 else
713 dentry = NULL;
714 return dentry;
715 }
716
717 static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
718 {
719 return ceph_ino(inode) == CEPH_INO_ROOT &&
720 strncmp(dentry->d_name.name, ".ceph", 5) == 0;
721 }
722
723 /*
724 * Look up a single dir entry. If there is a lookup intent, inform
725 * the MDS so that it gets our 'caps wanted' value in a single op.
726 */
727 static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
728 unsigned int flags)
729 {
730 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
731 struct ceph_mds_client *mdsc = fsc->mdsc;
732 struct ceph_mds_request *req;
733 int op;
734 int mask;
735 int err;
736
737 dout("lookup %p dentry %p '%pd'\n",
738 dir, dentry, dentry);
739
740 if (dentry->d_name.len > NAME_MAX)
741 return ERR_PTR(-ENAMETOOLONG);
742
743 /* can we conclude ENOENT locally? */
744 if (d_really_is_negative(dentry)) {
745 struct ceph_inode_info *ci = ceph_inode(dir);
746 struct ceph_dentry_info *di = ceph_dentry(dentry);
747
748 spin_lock(&ci->i_ceph_lock);
749 dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags);
750 if (strncmp(dentry->d_name.name,
751 fsc->mount_options->snapdir_name,
752 dentry->d_name.len) &&
753 !is_root_ceph_dentry(dir, dentry) &&
754 ceph_test_mount_opt(fsc, DCACHE) &&
755 __ceph_dir_is_complete(ci) &&
756 (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
757 spin_unlock(&ci->i_ceph_lock);
758 dout(" dir %p complete, -ENOENT\n", dir);
759 d_add(dentry, NULL);
760 di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
761 return NULL;
762 }
763 spin_unlock(&ci->i_ceph_lock);
764 }
765
766 op = ceph_snap(dir) == CEPH_SNAPDIR ?
767 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
768 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
769 if (IS_ERR(req))
770 return ERR_CAST(req);
771 req->r_dentry = dget(dentry);
772 req->r_num_caps = 2;
773
774 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
775 if (ceph_security_xattr_wanted(dir))
776 mask |= CEPH_CAP_XATTR_SHARED;
777 req->r_args.getattr.mask = cpu_to_le32(mask);
778
779 req->r_parent = dir;
780 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
781 err = ceph_mdsc_do_request(mdsc, NULL, req);
782 err = ceph_handle_snapdir(req, dentry, err);
783 dentry = ceph_finish_lookup(req, dentry, err);
784 ceph_mdsc_put_request(req); /* will dput(dentry) */
785 dout("lookup result=%p\n", dentry);
786 return dentry;
787 }
788
789 /*
790 * If we do a create but get no trace back from the MDS, follow up with
791 * a lookup (the VFS expects us to link up the provided dentry).
792 */
793 int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
794 {
795 struct dentry *result = ceph_lookup(dir, dentry, 0);
796
797 if (result && !IS_ERR(result)) {
798 /*
799 * We created the item, then did a lookup, and found
800 * it was already linked to another inode we already
801 * had in our cache (and thus got spliced). To not
802 * confuse VFS (especially when inode is a directory),
803 * we don't link our dentry to that inode, return an
804 * error instead.
805 *
806 * This event should be rare and it happens only when
807 * we talk to old MDS. Recent MDS does not send traceless
808 * reply for request that creates new inode.
809 */
810 d_drop(result);
811 return -ESTALE;
812 }
813 return PTR_ERR(result);
814 }
815
816 static int ceph_mknod(struct inode *dir, struct dentry *dentry,
817 umode_t mode, dev_t rdev)
818 {
819 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
820 struct ceph_mds_client *mdsc = fsc->mdsc;
821 struct ceph_mds_request *req;
822 struct ceph_acls_info acls = {};
823 int err;
824
825 if (ceph_snap(dir) != CEPH_NOSNAP)
826 return -EROFS;
827
828 err = ceph_pre_init_acls(dir, &mode, &acls);
829 if (err < 0)
830 return err;
831
832 dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
833 dir, dentry, mode, rdev);
834 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
835 if (IS_ERR(req)) {
836 err = PTR_ERR(req);
837 goto out;
838 }
839 req->r_dentry = dget(dentry);
840 req->r_num_caps = 2;
841 req->r_parent = dir;
842 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
843 req->r_args.mknod.mode = cpu_to_le32(mode);
844 req->r_args.mknod.rdev = cpu_to_le32(rdev);
845 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
846 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
847 if (acls.pagelist) {
848 req->r_pagelist = acls.pagelist;
849 acls.pagelist = NULL;
850 }
851 err = ceph_mdsc_do_request(mdsc, dir, req);
852 if (!err && !req->r_reply_info.head->is_dentry)
853 err = ceph_handle_notrace_create(dir, dentry);
854 ceph_mdsc_put_request(req);
855 out:
856 if (!err)
857 ceph_init_inode_acls(d_inode(dentry), &acls);
858 else
859 d_drop(dentry);
860 ceph_release_acls_info(&acls);
861 return err;
862 }
863
864 static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
865 bool excl)
866 {
867 return ceph_mknod(dir, dentry, mode, 0);
868 }
869
870 static int ceph_symlink(struct inode *dir, struct dentry *dentry,
871 const char *dest)
872 {
873 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
874 struct ceph_mds_client *mdsc = fsc->mdsc;
875 struct ceph_mds_request *req;
876 int err;
877
878 if (ceph_snap(dir) != CEPH_NOSNAP)
879 return -EROFS;
880
881 dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
882 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
883 if (IS_ERR(req)) {
884 err = PTR_ERR(req);
885 goto out;
886 }
887 req->r_path2 = kstrdup(dest, GFP_KERNEL);
888 if (!req->r_path2) {
889 err = -ENOMEM;
890 ceph_mdsc_put_request(req);
891 goto out;
892 }
893 req->r_parent = dir;
894 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
895 req->r_dentry = dget(dentry);
896 req->r_num_caps = 2;
897 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
898 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
899 err = ceph_mdsc_do_request(mdsc, dir, req);
900 if (!err && !req->r_reply_info.head->is_dentry)
901 err = ceph_handle_notrace_create(dir, dentry);
902 ceph_mdsc_put_request(req);
903 out:
904 if (err)
905 d_drop(dentry);
906 return err;
907 }
908
909 static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
910 {
911 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
912 struct ceph_mds_client *mdsc = fsc->mdsc;
913 struct ceph_mds_request *req;
914 struct ceph_acls_info acls = {};
915 int err = -EROFS;
916 int op;
917
918 if (ceph_snap(dir) == CEPH_SNAPDIR) {
919 /* mkdir .snap/foo is a MKSNAP */
920 op = CEPH_MDS_OP_MKSNAP;
921 dout("mksnap dir %p snap '%pd' dn %p\n", dir,
922 dentry, dentry);
923 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
924 dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
925 op = CEPH_MDS_OP_MKDIR;
926 } else {
927 goto out;
928 }
929
930 mode |= S_IFDIR;
931 err = ceph_pre_init_acls(dir, &mode, &acls);
932 if (err < 0)
933 goto out;
934
935 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
936 if (IS_ERR(req)) {
937 err = PTR_ERR(req);
938 goto out;
939 }
940
941 req->r_dentry = dget(dentry);
942 req->r_num_caps = 2;
943 req->r_parent = dir;
944 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
945 req->r_args.mkdir.mode = cpu_to_le32(mode);
946 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
947 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
948 if (acls.pagelist) {
949 req->r_pagelist = acls.pagelist;
950 acls.pagelist = NULL;
951 }
952 err = ceph_mdsc_do_request(mdsc, dir, req);
953 if (!err &&
954 !req->r_reply_info.head->is_target &&
955 !req->r_reply_info.head->is_dentry)
956 err = ceph_handle_notrace_create(dir, dentry);
957 ceph_mdsc_put_request(req);
958 out:
959 if (!err)
960 ceph_init_inode_acls(d_inode(dentry), &acls);
961 else
962 d_drop(dentry);
963 ceph_release_acls_info(&acls);
964 return err;
965 }
966
967 static int ceph_link(struct dentry *old_dentry, struct inode *dir,
968 struct dentry *dentry)
969 {
970 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
971 struct ceph_mds_client *mdsc = fsc->mdsc;
972 struct ceph_mds_request *req;
973 int err;
974
975 if (ceph_snap(dir) != CEPH_NOSNAP)
976 return -EROFS;
977
978 dout("link in dir %p old_dentry %p dentry %p\n", dir,
979 old_dentry, dentry);
980 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
981 if (IS_ERR(req)) {
982 d_drop(dentry);
983 return PTR_ERR(req);
984 }
985 req->r_dentry = dget(dentry);
986 req->r_num_caps = 2;
987 req->r_old_dentry = dget(old_dentry);
988 req->r_parent = dir;
989 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
990 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
991 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
992 /* release LINK_SHARED on source inode (mds will lock it) */
993 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
994 err = ceph_mdsc_do_request(mdsc, dir, req);
995 if (err) {
996 d_drop(dentry);
997 } else if (!req->r_reply_info.head->is_dentry) {
998 ihold(d_inode(old_dentry));
999 d_instantiate(dentry, d_inode(old_dentry));
1000 }
1001 ceph_mdsc_put_request(req);
1002 return err;
1003 }
1004
1005 /*
1006 * rmdir and unlink are differ only by the metadata op code
1007 */
1008 static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1009 {
1010 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
1011 struct ceph_mds_client *mdsc = fsc->mdsc;
1012 struct inode *inode = d_inode(dentry);
1013 struct ceph_mds_request *req;
1014 int err = -EROFS;
1015 int op;
1016
1017 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1018 /* rmdir .snap/foo is RMSNAP */
1019 dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry);
1020 op = CEPH_MDS_OP_RMSNAP;
1021 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1022 dout("unlink/rmdir dir %p dn %p inode %p\n",
1023 dir, dentry, inode);
1024 op = d_is_dir(dentry) ?
1025 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1026 } else
1027 goto out;
1028 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1029 if (IS_ERR(req)) {
1030 err = PTR_ERR(req);
1031 goto out;
1032 }
1033 req->r_dentry = dget(dentry);
1034 req->r_num_caps = 2;
1035 req->r_parent = dir;
1036 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1037 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1038 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1039 req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1040 err = ceph_mdsc_do_request(mdsc, dir, req);
1041 if (!err && !req->r_reply_info.head->is_dentry)
1042 d_delete(dentry);
1043 ceph_mdsc_put_request(req);
1044 out:
1045 return err;
1046 }
1047
1048 static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
1049 struct inode *new_dir, struct dentry *new_dentry,
1050 unsigned int flags)
1051 {
1052 struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
1053 struct ceph_mds_client *mdsc = fsc->mdsc;
1054 struct ceph_mds_request *req;
1055 int op = CEPH_MDS_OP_RENAME;
1056 int err;
1057
1058 if (flags)
1059 return -EINVAL;
1060
1061 if (ceph_snap(old_dir) != ceph_snap(new_dir))
1062 return -EXDEV;
1063 if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1064 if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1065 op = CEPH_MDS_OP_RENAMESNAP;
1066 else
1067 return -EROFS;
1068 }
1069 dout("rename dir %p dentry %p to dir %p dentry %p\n",
1070 old_dir, old_dentry, new_dir, new_dentry);
1071 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1072 if (IS_ERR(req))
1073 return PTR_ERR(req);
1074 ihold(old_dir);
1075 req->r_dentry = dget(new_dentry);
1076 req->r_num_caps = 2;
1077 req->r_old_dentry = dget(old_dentry);
1078 req->r_old_dentry_dir = old_dir;
1079 req->r_parent = new_dir;
1080 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1081 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
1082 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1083 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1084 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1085 /* release LINK_RDCACHE on source inode (mds will lock it) */
1086 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1087 if (d_really_is_positive(new_dentry)) {
1088 req->r_inode_drop =
1089 ceph_drop_caps_for_unlink(d_inode(new_dentry));
1090 }
1091 err = ceph_mdsc_do_request(mdsc, old_dir, req);
1092 if (!err && !req->r_reply_info.head->is_dentry) {
1093 /*
1094 * Normally d_move() is done by fill_trace (called by
1095 * do_request, above). If there is no trace, we need
1096 * to do it here.
1097 */
1098 d_move(old_dentry, new_dentry);
1099 }
1100 ceph_mdsc_put_request(req);
1101 return err;
1102 }
1103
1104 /*
1105 * Ensure a dentry lease will no longer revalidate.
1106 */
1107 void ceph_invalidate_dentry_lease(struct dentry *dentry)
1108 {
1109 spin_lock(&dentry->d_lock);
1110 ceph_dentry(dentry)->time = jiffies;
1111 ceph_dentry(dentry)->lease_shared_gen = 0;
1112 spin_unlock(&dentry->d_lock);
1113 }
1114
1115 /*
1116 * Check if dentry lease is valid. If not, delete the lease. Try to
1117 * renew if the least is more than half up.
1118 */
1119 static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags,
1120 struct inode *dir)
1121 {
1122 struct ceph_dentry_info *di;
1123 struct ceph_mds_session *s;
1124 int valid = 0;
1125 u32 gen;
1126 unsigned long ttl;
1127 struct ceph_mds_session *session = NULL;
1128 u32 seq = 0;
1129
1130 spin_lock(&dentry->d_lock);
1131 di = ceph_dentry(dentry);
1132 if (di && di->lease_session) {
1133 s = di->lease_session;
1134 spin_lock(&s->s_gen_ttl_lock);
1135 gen = s->s_cap_gen;
1136 ttl = s->s_cap_ttl;
1137 spin_unlock(&s->s_gen_ttl_lock);
1138
1139 if (di->lease_gen == gen &&
1140 time_before(jiffies, di->time) &&
1141 time_before(jiffies, ttl)) {
1142 valid = 1;
1143 if (di->lease_renew_after &&
1144 time_after(jiffies, di->lease_renew_after)) {
1145 /*
1146 * We should renew. If we're in RCU walk mode
1147 * though, we can't do that so just return
1148 * -ECHILD.
1149 */
1150 if (flags & LOOKUP_RCU) {
1151 valid = -ECHILD;
1152 } else {
1153 session = ceph_get_mds_session(s);
1154 seq = di->lease_seq;
1155 di->lease_renew_after = 0;
1156 di->lease_renew_from = jiffies;
1157 }
1158 }
1159 }
1160 }
1161 spin_unlock(&dentry->d_lock);
1162
1163 if (session) {
1164 ceph_mdsc_lease_send_msg(session, dir, dentry,
1165 CEPH_MDS_LEASE_RENEW, seq);
1166 ceph_put_mds_session(session);
1167 }
1168 dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1169 return valid;
1170 }
1171
1172 /*
1173 * Check if directory-wide content lease/cap is valid.
1174 */
1175 static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
1176 {
1177 struct ceph_inode_info *ci = ceph_inode(dir);
1178 struct ceph_dentry_info *di = ceph_dentry(dentry);
1179 int valid = 0;
1180
1181 spin_lock(&ci->i_ceph_lock);
1182 if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen)
1183 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1184 spin_unlock(&ci->i_ceph_lock);
1185 dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
1186 dir, (unsigned)atomic_read(&ci->i_shared_gen),
1187 dentry, (unsigned)di->lease_shared_gen, valid);
1188 return valid;
1189 }
1190
1191 /*
1192 * Check if cached dentry can be trusted.
1193 */
1194 static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1195 {
1196 int valid = 0;
1197 struct dentry *parent;
1198 struct inode *dir;
1199
1200 if (flags & LOOKUP_RCU) {
1201 parent = READ_ONCE(dentry->d_parent);
1202 dir = d_inode_rcu(parent);
1203 if (!dir)
1204 return -ECHILD;
1205 } else {
1206 parent = dget_parent(dentry);
1207 dir = d_inode(parent);
1208 }
1209
1210 dout("d_revalidate %p '%pd' inode %p offset %lld\n", dentry,
1211 dentry, d_inode(dentry), ceph_dentry(dentry)->offset);
1212
1213 /* always trust cached snapped dentries, snapdir dentry */
1214 if (ceph_snap(dir) != CEPH_NOSNAP) {
1215 dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
1216 dentry, d_inode(dentry));
1217 valid = 1;
1218 } else if (d_really_is_positive(dentry) &&
1219 ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
1220 valid = 1;
1221 } else {
1222 valid = dentry_lease_is_valid(dentry, flags, dir);
1223 if (valid == -ECHILD)
1224 return valid;
1225 if (valid || dir_lease_is_valid(dir, dentry)) {
1226 if (d_really_is_positive(dentry))
1227 valid = ceph_is_any_caps(d_inode(dentry));
1228 else
1229 valid = 1;
1230 }
1231 }
1232
1233 if (!valid) {
1234 struct ceph_mds_client *mdsc =
1235 ceph_sb_to_client(dir->i_sb)->mdsc;
1236 struct ceph_mds_request *req;
1237 int op, err;
1238 u32 mask;
1239
1240 if (flags & LOOKUP_RCU)
1241 return -ECHILD;
1242
1243 op = ceph_snap(dir) == CEPH_SNAPDIR ?
1244 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
1245 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
1246 if (!IS_ERR(req)) {
1247 req->r_dentry = dget(dentry);
1248 req->r_num_caps = 2;
1249 req->r_parent = dir;
1250
1251 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
1252 if (ceph_security_xattr_wanted(dir))
1253 mask |= CEPH_CAP_XATTR_SHARED;
1254 req->r_args.getattr.mask = cpu_to_le32(mask);
1255
1256 err = ceph_mdsc_do_request(mdsc, NULL, req);
1257 switch (err) {
1258 case 0:
1259 if (d_really_is_positive(dentry) &&
1260 d_inode(dentry) == req->r_target_inode)
1261 valid = 1;
1262 break;
1263 case -ENOENT:
1264 if (d_really_is_negative(dentry))
1265 valid = 1;
1266 /* Fallthrough */
1267 default:
1268 break;
1269 }
1270 ceph_mdsc_put_request(req);
1271 dout("d_revalidate %p lookup result=%d\n",
1272 dentry, err);
1273 }
1274 }
1275
1276 dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1277 if (valid) {
1278 ceph_dentry_lru_touch(dentry);
1279 } else {
1280 ceph_dir_clear_complete(dir);
1281 }
1282
1283 if (!(flags & LOOKUP_RCU))
1284 dput(parent);
1285 return valid;
1286 }
1287
1288 /*
1289 * Release our ceph_dentry_info.
1290 */
1291 static void ceph_d_release(struct dentry *dentry)
1292 {
1293 struct ceph_dentry_info *di = ceph_dentry(dentry);
1294
1295 dout("d_release %p\n", dentry);
1296 ceph_dentry_lru_del(dentry);
1297
1298 spin_lock(&dentry->d_lock);
1299 dentry->d_fsdata = NULL;
1300 spin_unlock(&dentry->d_lock);
1301
1302 if (di->lease_session)
1303 ceph_put_mds_session(di->lease_session);
1304 kmem_cache_free(ceph_dentry_cachep, di);
1305 }
1306
1307 /*
1308 * When the VFS prunes a dentry from the cache, we need to clear the
1309 * complete flag on the parent directory.
1310 *
1311 * Called under dentry->d_lock.
1312 */
1313 static void ceph_d_prune(struct dentry *dentry)
1314 {
1315 struct ceph_inode_info *dir_ci;
1316 struct ceph_dentry_info *di;
1317
1318 dout("ceph_d_prune %pd %p\n", dentry, dentry);
1319
1320 /* do we have a valid parent? */
1321 if (IS_ROOT(dentry))
1322 return;
1323
1324 /* we hold d_lock, so d_parent is stable */
1325 dir_ci = ceph_inode(d_inode(dentry->d_parent));
1326 if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
1327 return;
1328
1329 /* who calls d_delete() should also disable dcache readdir */
1330 if (d_really_is_negative(dentry))
1331 return;
1332
1333 /* d_fsdata does not get cleared until d_release */
1334 if (!d_unhashed(dentry)) {
1335 __ceph_dir_clear_complete(dir_ci);
1336 return;
1337 }
1338
1339 /* Disable dcache readdir just in case that someone called d_drop()
1340 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
1341 * properly (dcache readdir is still enabled) */
1342 di = ceph_dentry(dentry);
1343 if (di->offset > 0 &&
1344 di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
1345 __ceph_dir_clear_ordered(dir_ci);
1346 }
1347
1348 /*
1349 * read() on a dir. This weird interface hack only works if mounted
1350 * with '-o dirstat'.
1351 */
1352 static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1353 loff_t *ppos)
1354 {
1355 struct ceph_file_info *cf = file->private_data;
1356 struct inode *inode = file_inode(file);
1357 struct ceph_inode_info *ci = ceph_inode(inode);
1358 int left;
1359 const int bufsize = 1024;
1360
1361 if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1362 return -EISDIR;
1363
1364 if (!cf->dir_info) {
1365 cf->dir_info = kmalloc(bufsize, GFP_KERNEL);
1366 if (!cf->dir_info)
1367 return -ENOMEM;
1368 cf->dir_info_len =
1369 snprintf(cf->dir_info, bufsize,
1370 "entries: %20lld\n"
1371 " files: %20lld\n"
1372 " subdirs: %20lld\n"
1373 "rentries: %20lld\n"
1374 " rfiles: %20lld\n"
1375 " rsubdirs: %20lld\n"
1376 "rbytes: %20lld\n"
1377 "rctime: %10ld.%09ld\n",
1378 ci->i_files + ci->i_subdirs,
1379 ci->i_files,
1380 ci->i_subdirs,
1381 ci->i_rfiles + ci->i_rsubdirs,
1382 ci->i_rfiles,
1383 ci->i_rsubdirs,
1384 ci->i_rbytes,
1385 (long)ci->i_rctime.tv_sec,
1386 (long)ci->i_rctime.tv_nsec);
1387 }
1388
1389 if (*ppos >= cf->dir_info_len)
1390 return 0;
1391 size = min_t(unsigned, size, cf->dir_info_len-*ppos);
1392 left = copy_to_user(buf, cf->dir_info + *ppos, size);
1393 if (left == size)
1394 return -EFAULT;
1395 *ppos += (size - left);
1396 return size - left;
1397 }
1398
1399 /*
1400 * We maintain a private dentry LRU.
1401 *
1402 * FIXME: this needs to be changed to a per-mds lru to be useful.
1403 */
1404 void ceph_dentry_lru_add(struct dentry *dn)
1405 {
1406 struct ceph_dentry_info *di = ceph_dentry(dn);
1407 struct ceph_mds_client *mdsc;
1408
1409 dout("dentry_lru_add %p %p '%pd'\n", di, dn, dn);
1410 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1411 spin_lock(&mdsc->dentry_lru_lock);
1412 list_add_tail(&di->lru, &mdsc->dentry_lru);
1413 mdsc->num_dentry++;
1414 spin_unlock(&mdsc->dentry_lru_lock);
1415 }
1416
1417 void ceph_dentry_lru_touch(struct dentry *dn)
1418 {
1419 struct ceph_dentry_info *di = ceph_dentry(dn);
1420 struct ceph_mds_client *mdsc;
1421
1422 dout("dentry_lru_touch %p %p '%pd' (offset %lld)\n", di, dn, dn,
1423 di->offset);
1424 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1425 spin_lock(&mdsc->dentry_lru_lock);
1426 list_move_tail(&di->lru, &mdsc->dentry_lru);
1427 spin_unlock(&mdsc->dentry_lru_lock);
1428 }
1429
1430 void ceph_dentry_lru_del(struct dentry *dn)
1431 {
1432 struct ceph_dentry_info *di = ceph_dentry(dn);
1433 struct ceph_mds_client *mdsc;
1434
1435 dout("dentry_lru_del %p %p '%pd'\n", di, dn, dn);
1436 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1437 spin_lock(&mdsc->dentry_lru_lock);
1438 list_del_init(&di->lru);
1439 mdsc->num_dentry--;
1440 spin_unlock(&mdsc->dentry_lru_lock);
1441 }
1442
1443 /*
1444 * Return name hash for a given dentry. This is dependent on
1445 * the parent directory's hash function.
1446 */
1447 unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1448 {
1449 struct ceph_inode_info *dci = ceph_inode(dir);
1450
1451 switch (dci->i_dir_layout.dl_dir_hash) {
1452 case 0: /* for backward compat */
1453 case CEPH_STR_HASH_LINUX:
1454 return dn->d_name.hash;
1455
1456 default:
1457 return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
1458 dn->d_name.name, dn->d_name.len);
1459 }
1460 }
1461
1462 const struct file_operations ceph_dir_fops = {
1463 .read = ceph_read_dir,
1464 .iterate = ceph_readdir,
1465 .llseek = ceph_dir_llseek,
1466 .open = ceph_open,
1467 .release = ceph_release,
1468 .unlocked_ioctl = ceph_ioctl,
1469 .fsync = ceph_fsync,
1470 };
1471
1472 const struct file_operations ceph_snapdir_fops = {
1473 .iterate = ceph_readdir,
1474 .llseek = ceph_dir_llseek,
1475 .open = ceph_open,
1476 .release = ceph_release,
1477 };
1478
1479 const struct inode_operations ceph_dir_iops = {
1480 .lookup = ceph_lookup,
1481 .permission = ceph_permission,
1482 .getattr = ceph_getattr,
1483 .setattr = ceph_setattr,
1484 .listxattr = ceph_listxattr,
1485 .get_acl = ceph_get_acl,
1486 .set_acl = ceph_set_acl,
1487 .mknod = ceph_mknod,
1488 .symlink = ceph_symlink,
1489 .mkdir = ceph_mkdir,
1490 .link = ceph_link,
1491 .unlink = ceph_unlink,
1492 .rmdir = ceph_unlink,
1493 .rename = ceph_rename,
1494 .create = ceph_create,
1495 .atomic_open = ceph_atomic_open,
1496 };
1497
1498 const struct inode_operations ceph_snapdir_iops = {
1499 .lookup = ceph_lookup,
1500 .permission = ceph_permission,
1501 .getattr = ceph_getattr,
1502 .mkdir = ceph_mkdir,
1503 .rmdir = ceph_unlink,
1504 .rename = ceph_rename,
1505 };
1506
1507 const struct dentry_operations ceph_dentry_ops = {
1508 .d_revalidate = ceph_d_revalidate,
1509 .d_release = ceph_d_release,
1510 .d_prune = ceph_d_prune,
1511 .d_init = ceph_d_init,
1512 };
CRIS linux kernel tree