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1#include <linux/ceph/ceph_debug.h>
2
3#include <linux/spinlock.h>
4#include <linux/fs_struct.h>
5#include <linux/namei.h>
6#include <linux/slab.h>
7#include <linux/sched.h>
8
9#include "super.h"
10#include "mds_client.h"
11
12/*
13 * Directory operations: readdir, lookup, create, link, unlink,
14 * rename, etc.
15 */
16
17/*
18 * Ceph MDS operations are specified in terms of a base ino and
19 * relative path. Thus, the client can specify an operation on a
20 * specific inode (e.g., a getattr due to fstat(2)), or as a path
21 * relative to, say, the root directory.
22 *
23 * Normally, we limit ourselves to strict inode ops (no path component)
24 * or dentry operations (a single path component relative to an ino). The
25 * exception to this is open_root_dentry(), which will open the mount
26 * point by name.
27 */
28
29const struct inode_operations ceph_dir_iops;
30const struct file_operations ceph_dir_fops;
31const struct dentry_operations ceph_dentry_ops;
32
33/*
34 * Initialize ceph dentry state.
35 */
36int ceph_init_dentry(struct dentry *dentry)
37{
38 struct ceph_dentry_info *di;
39
40 if (dentry->d_fsdata)
41 return 0;
42
43 di = kmem_cache_alloc(ceph_dentry_cachep, GFP_NOFS | __GFP_ZERO);
44 if (!di)
45 return -ENOMEM; /* oh well */
46
47 spin_lock(&dentry->d_lock);
48 if (dentry->d_fsdata) {
49 /* lost a race */
50 kmem_cache_free(ceph_dentry_cachep, di);
51 goto out_unlock;
52 }
53
54 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP)
55 d_set_d_op(dentry, &ceph_dentry_ops);
56 else if (ceph_snap(dentry->d_parent->d_inode) == CEPH_SNAPDIR)
57 d_set_d_op(dentry, &ceph_snapdir_dentry_ops);
58 else
59 d_set_d_op(dentry, &ceph_snap_dentry_ops);
60
61 di->dentry = dentry;
62 di->lease_session = NULL;
63 dentry->d_time = jiffies;
64 /* avoid reordering d_fsdata setup so that the check above is safe */
65 smp_mb();
66 dentry->d_fsdata = di;
67 ceph_dentry_lru_add(dentry);
68out_unlock:
69 spin_unlock(&dentry->d_lock);
70 return 0;
71}
72
73struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry)
74{
75 struct inode *inode = NULL;
76
77 if (!dentry)
78 return NULL;
79
80 spin_lock(&dentry->d_lock);
81 if (!IS_ROOT(dentry)) {
82 inode = dentry->d_parent->d_inode;
83 ihold(inode);
84 }
85 spin_unlock(&dentry->d_lock);
86 return inode;
87}
88
89
90/*
91 * for readdir, we encode the directory frag and offset within that
92 * frag into f_pos.
93 */
94static unsigned fpos_frag(loff_t p)
95{
96 return p >> 32;
97}
98static unsigned fpos_off(loff_t p)
99{
100 return p & 0xffffffff;
101}
102
103static int fpos_cmp(loff_t l, loff_t r)
104{
105 int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
106 if (v)
107 return v;
108 return (int)(fpos_off(l) - fpos_off(r));
109}
110
111/*
112 * When possible, we try to satisfy a readdir by peeking at the
113 * dcache. We make this work by carefully ordering dentries on
114 * d_u.d_child when we initially get results back from the MDS, and
115 * falling back to a "normal" sync readdir if any dentries in the dir
116 * are dropped.
117 *
118 * Complete dir indicates that we have all dentries in the dir. It is
119 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
120 * the MDS if/when the directory is modified).
121 */
122static int __dcache_readdir(struct file *file, struct dir_context *ctx,
123 u32 shared_gen)
124{
125 struct ceph_file_info *fi = file->private_data;
126 struct dentry *parent = file->f_dentry;
127 struct inode *dir = parent->d_inode;
128 struct list_head *p;
129 struct dentry *dentry, *last;
130 struct ceph_dentry_info *di;
131 int err = 0;
132
133 /* claim ref on last dentry we returned */
134 last = fi->dentry;
135 fi->dentry = NULL;
136
137 dout("__dcache_readdir %p v%u at %llu (last %p)\n",
138 dir, shared_gen, ctx->pos, last);
139
140 spin_lock(&parent->d_lock);
141
142 /* start at beginning? */
143 if (ctx->pos == 2 || last == NULL ||
144 fpos_cmp(ctx->pos, ceph_dentry(last)->offset) < 0) {
145 if (list_empty(&parent->d_subdirs))
146 goto out_unlock;
147 p = parent->d_subdirs.prev;
148 dout(" initial p %p/%p\n", p->prev, p->next);
149 } else {
150 p = last->d_u.d_child.prev;
151 }
152
153more:
154 dentry = list_entry(p, struct dentry, d_u.d_child);
155 di = ceph_dentry(dentry);
156 while (1) {
157 dout(" p %p/%p %s d_subdirs %p/%p\n", p->prev, p->next,
158 d_unhashed(dentry) ? "!hashed" : "hashed",
159 parent->d_subdirs.prev, parent->d_subdirs.next);
160 if (p == &parent->d_subdirs) {
161 fi->flags |= CEPH_F_ATEND;
162 goto out_unlock;
163 }
164 spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
165 if (di->lease_shared_gen == shared_gen &&
166 !d_unhashed(dentry) && dentry->d_inode &&
167 ceph_snap(dentry->d_inode) != CEPH_SNAPDIR &&
168 ceph_ino(dentry->d_inode) != CEPH_INO_CEPH &&
169 fpos_cmp(ctx->pos, di->offset) <= 0)
170 break;
171 dout(" skipping %p %.*s at %llu (%llu)%s%s\n", dentry,
172 dentry->d_name.len, dentry->d_name.name, di->offset,
173 ctx->pos, d_unhashed(dentry) ? " unhashed" : "",
174 !dentry->d_inode ? " null" : "");
175 spin_unlock(&dentry->d_lock);
176 p = p->prev;
177 dentry = list_entry(p, struct dentry, d_u.d_child);
178 di = ceph_dentry(dentry);
179 }
180
181 dget_dlock(dentry);
182 spin_unlock(&dentry->d_lock);
183 spin_unlock(&parent->d_lock);
184
185 /* make sure a dentry wasn't dropped while we didn't have parent lock */
186 if (!ceph_dir_is_complete(dir)) {
187 dout(" lost dir complete on %p; falling back to mds\n", dir);
188 dput(dentry);
189 err = -EAGAIN;
190 goto out;
191 }
192
193 dout(" %llu (%llu) dentry %p %.*s %p\n", di->offset, ctx->pos,
194 dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
195 if (!dir_emit(ctx, dentry->d_name.name,
196 dentry->d_name.len,
197 ceph_translate_ino(dentry->d_sb, dentry->d_inode->i_ino),
198 dentry->d_inode->i_mode >> 12)) {
199 if (last) {
200 /* remember our position */
201 fi->dentry = last;
202 fi->next_offset = fpos_off(di->offset);
203 }
204 dput(dentry);
205 return 0;
206 }
207
208 ctx->pos = di->offset + 1;
209
210 if (last)
211 dput(last);
212 last = dentry;
213
214 spin_lock(&parent->d_lock);
215 p = p->prev; /* advance to next dentry */
216 goto more;
217
218out_unlock:
219 spin_unlock(&parent->d_lock);
220out:
221 if (last)
222 dput(last);
223 return err;
224}
225
226/*
227 * make note of the last dentry we read, so we can
228 * continue at the same lexicographical point,
229 * regardless of what dir changes take place on the
230 * server.
231 */
232static int note_last_dentry(struct ceph_file_info *fi, const char *name,
233 int len)
234{
235 kfree(fi->last_name);
236 fi->last_name = kmalloc(len+1, GFP_NOFS);
237 if (!fi->last_name)
238 return -ENOMEM;
239 memcpy(fi->last_name, name, len);
240 fi->last_name[len] = 0;
241 dout("note_last_dentry '%s'\n", fi->last_name);
242 return 0;
243}
244
245static int ceph_readdir(struct file *file, struct dir_context *ctx)
246{
247 struct ceph_file_info *fi = file->private_data;
248 struct inode *inode = file_inode(file);
249 struct ceph_inode_info *ci = ceph_inode(inode);
250 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
251 struct ceph_mds_client *mdsc = fsc->mdsc;
252 unsigned frag = fpos_frag(ctx->pos);
253 int off = fpos_off(ctx->pos);
254 int err;
255 u32 ftype;
256 struct ceph_mds_reply_info_parsed *rinfo;
257
258 dout("readdir %p file %p frag %u off %u\n", inode, file, frag, off);
259 if (fi->flags & CEPH_F_ATEND)
260 return 0;
261
262 /* always start with . and .. */
263 if (ctx->pos == 0) {
264 /* note dir version at start of readdir so we can tell
265 * if any dentries get dropped */
266 fi->dir_release_count = atomic_read(&ci->i_release_count);
267
268 dout("readdir off 0 -> '.'\n");
269 if (!dir_emit(ctx, ".", 1,
270 ceph_translate_ino(inode->i_sb, inode->i_ino),
271 inode->i_mode >> 12))
272 return 0;
273 ctx->pos = 1;
274 off = 1;
275 }
276 if (ctx->pos == 1) {
277 ino_t ino = parent_ino(file->f_dentry);
278 dout("readdir off 1 -> '..'\n");
279 if (!dir_emit(ctx, "..", 2,
280 ceph_translate_ino(inode->i_sb, ino),
281 inode->i_mode >> 12))
282 return 0;
283 ctx->pos = 2;
284 off = 2;
285 }
286
287 /* can we use the dcache? */
288 spin_lock(&ci->i_ceph_lock);
289 if ((ctx->pos == 2 || fi->dentry) &&
290 !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
291 ceph_snap(inode) != CEPH_SNAPDIR &&
292 __ceph_dir_is_complete(ci) &&
293 __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
294 u32 shared_gen = ci->i_shared_gen;
295 spin_unlock(&ci->i_ceph_lock);
296 err = __dcache_readdir(file, ctx, shared_gen);
297 if (err != -EAGAIN)
298 return err;
299 frag = fpos_frag(ctx->pos);
300 off = fpos_off(ctx->pos);
301 } else {
302 spin_unlock(&ci->i_ceph_lock);
303 }
304 if (fi->dentry) {
305 err = note_last_dentry(fi, fi->dentry->d_name.name,
306 fi->dentry->d_name.len);
307 if (err)
308 return err;
309 dput(fi->dentry);
310 fi->dentry = NULL;
311 }
312
313 /* proceed with a normal readdir */
314
315more:
316 /* do we have the correct frag content buffered? */
317 if (fi->frag != frag || fi->last_readdir == NULL) {
318 struct ceph_mds_request *req;
319 int op = ceph_snap(inode) == CEPH_SNAPDIR ?
320 CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
321
322 /* discard old result, if any */
323 if (fi->last_readdir) {
324 ceph_mdsc_put_request(fi->last_readdir);
325 fi->last_readdir = NULL;
326 }
327
328 dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
329 ceph_vinop(inode), frag, fi->last_name);
330 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
331 if (IS_ERR(req))
332 return PTR_ERR(req);
333 err = ceph_alloc_readdir_reply_buffer(req, inode);
334 if (err) {
335 ceph_mdsc_put_request(req);
336 return err;
337 }
338 req->r_inode = inode;
339 ihold(inode);
340 req->r_dentry = dget(file->f_dentry);
341 /* hints to request -> mds selection code */
342 req->r_direct_mode = USE_AUTH_MDS;
343 req->r_direct_hash = ceph_frag_value(frag);
344 req->r_direct_is_hash = true;
345 req->r_path2 = kstrdup(fi->last_name, GFP_NOFS);
346 req->r_readdir_offset = fi->next_offset;
347 req->r_args.readdir.frag = cpu_to_le32(frag);
348 err = ceph_mdsc_do_request(mdsc, NULL, req);
349 if (err < 0) {
350 ceph_mdsc_put_request(req);
351 return err;
352 }
353 dout("readdir got and parsed readdir result=%d"
354 " on frag %x, end=%d, complete=%d\n", err, frag,
355 (int)req->r_reply_info.dir_end,
356 (int)req->r_reply_info.dir_complete);
357
358 if (!req->r_did_prepopulate) {
359 dout("readdir !did_prepopulate");
360 /* preclude from marking dir complete */
361 fi->dir_release_count--;
362 }
363
364 /* note next offset and last dentry name */
365 rinfo = &req->r_reply_info;
366 if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
367 frag = le32_to_cpu(rinfo->dir_dir->frag);
368 if (ceph_frag_is_leftmost(frag))
369 fi->next_offset = 2;
370 else
371 fi->next_offset = 0;
372 off = fi->next_offset;
373 }
374 fi->frag = frag;
375 fi->offset = fi->next_offset;
376 fi->last_readdir = req;
377
378 if (req->r_reply_info.dir_end) {
379 kfree(fi->last_name);
380 fi->last_name = NULL;
381 if (ceph_frag_is_rightmost(frag))
382 fi->next_offset = 2;
383 else
384 fi->next_offset = 0;
385 } else {
386 err = note_last_dentry(fi,
387 rinfo->dir_dname[rinfo->dir_nr-1],
388 rinfo->dir_dname_len[rinfo->dir_nr-1]);
389 if (err)
390 return err;
391 fi->next_offset += rinfo->dir_nr;
392 }
393 }
394
395 rinfo = &fi->last_readdir->r_reply_info;
396 dout("readdir frag %x num %d off %d chunkoff %d\n", frag,
397 rinfo->dir_nr, off, fi->offset);
398
399 ctx->pos = ceph_make_fpos(frag, off);
400 while (off >= fi->offset && off - fi->offset < rinfo->dir_nr) {
401 struct ceph_mds_reply_inode *in =
402 rinfo->dir_in[off - fi->offset].in;
403 struct ceph_vino vino;
404 ino_t ino;
405
406 dout("readdir off %d (%d/%d) -> %lld '%.*s' %p\n",
407 off, off - fi->offset, rinfo->dir_nr, ctx->pos,
408 rinfo->dir_dname_len[off - fi->offset],
409 rinfo->dir_dname[off - fi->offset], in);
410 BUG_ON(!in);
411 ftype = le32_to_cpu(in->mode) >> 12;
412 vino.ino = le64_to_cpu(in->ino);
413 vino.snap = le64_to_cpu(in->snapid);
414 ino = ceph_vino_to_ino(vino);
415 if (!dir_emit(ctx,
416 rinfo->dir_dname[off - fi->offset],
417 rinfo->dir_dname_len[off - fi->offset],
418 ceph_translate_ino(inode->i_sb, ino), ftype)) {
419 dout("filldir stopping us...\n");
420 return 0;
421 }
422 off++;
423 ctx->pos++;
424 }
425
426 if (fi->last_name) {
427 ceph_mdsc_put_request(fi->last_readdir);
428 fi->last_readdir = NULL;
429 goto more;
430 }
431
432 /* more frags? */
433 if (!ceph_frag_is_rightmost(frag)) {
434 frag = ceph_frag_next(frag);
435 off = 0;
436 ctx->pos = ceph_make_fpos(frag, off);
437 dout("readdir next frag is %x\n", frag);
438 goto more;
439 }
440 fi->flags |= CEPH_F_ATEND;
441
442 /*
443 * if dir_release_count still matches the dir, no dentries
444 * were released during the whole readdir, and we should have
445 * the complete dir contents in our cache.
446 */
447 spin_lock(&ci->i_ceph_lock);
448 if (atomic_read(&ci->i_release_count) == fi->dir_release_count) {
449 dout(" marking %p complete\n", inode);
450 __ceph_dir_set_complete(ci, fi->dir_release_count);
451 }
452 spin_unlock(&ci->i_ceph_lock);
453
454 dout("readdir %p file %p done.\n", inode, file);
455 return 0;
456}
457
458static void reset_readdir(struct ceph_file_info *fi, unsigned frag)
459{
460 if (fi->last_readdir) {
461 ceph_mdsc_put_request(fi->last_readdir);
462 fi->last_readdir = NULL;
463 }
464 kfree(fi->last_name);
465 fi->last_name = NULL;
466 if (ceph_frag_is_leftmost(frag))
467 fi->next_offset = 2; /* compensate for . and .. */
468 else
469 fi->next_offset = 0;
470 if (fi->dentry) {
471 dput(fi->dentry);
472 fi->dentry = NULL;
473 }
474 fi->flags &= ~CEPH_F_ATEND;
475}
476
477static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
478{
479 struct ceph_file_info *fi = file->private_data;
480 struct inode *inode = file->f_mapping->host;
481 loff_t old_offset = ceph_make_fpos(fi->frag, fi->next_offset);
482 loff_t retval;
483
484 mutex_lock(&inode->i_mutex);
485 retval = -EINVAL;
486 switch (whence) {
487 case SEEK_END:
488 offset += inode->i_size + 2; /* FIXME */
489 break;
490 case SEEK_CUR:
491 offset += file->f_pos;
492 case SEEK_SET:
493 break;
494 default:
495 goto out;
496 }
497
498 if (offset >= 0) {
499 if (offset != file->f_pos) {
500 file->f_pos = offset;
501 file->f_version = 0;
502 fi->flags &= ~CEPH_F_ATEND;
503 }
504 retval = offset;
505
506 /*
507 * discard buffered readdir content on seekdir(0), or
508 * seek to new frag, or seek prior to current chunk.
509 */
510 if (offset == 0 ||
511 fpos_frag(offset) != fi->frag ||
512 fpos_off(offset) < fi->offset) {
513 dout("dir_llseek dropping %p content\n", file);
514 reset_readdir(fi, fpos_frag(offset));
515 }
516
517 /* bump dir_release_count if we did a forward seek */
518 if (fpos_cmp(offset, old_offset) > 0)
519 fi->dir_release_count--;
520 }
521out:
522 mutex_unlock(&inode->i_mutex);
523 return retval;
524}
525
526/*
527 * Handle lookups for the hidden .snap directory.
528 */
529int ceph_handle_snapdir(struct ceph_mds_request *req,
530 struct dentry *dentry, int err)
531{
532 struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
533 struct inode *parent = dentry->d_parent->d_inode; /* we hold i_mutex */
534
535 /* .snap dir? */
536 if (err == -ENOENT &&
537 ceph_snap(parent) == CEPH_NOSNAP &&
538 strcmp(dentry->d_name.name,
539 fsc->mount_options->snapdir_name) == 0) {
540 struct inode *inode = ceph_get_snapdir(parent);
541 dout("ENOENT on snapdir %p '%.*s', linking to snapdir %p\n",
542 dentry, dentry->d_name.len, dentry->d_name.name, inode);
543 BUG_ON(!d_unhashed(dentry));
544 d_add(dentry, inode);
545 err = 0;
546 }
547 return err;
548}
549
550/*
551 * Figure out final result of a lookup/open request.
552 *
553 * Mainly, make sure we return the final req->r_dentry (if it already
554 * existed) in place of the original VFS-provided dentry when they
555 * differ.
556 *
557 * Gracefully handle the case where the MDS replies with -ENOENT and
558 * no trace (which it may do, at its discretion, e.g., if it doesn't
559 * care to issue a lease on the negative dentry).
560 */
561struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
562 struct dentry *dentry, int err)
563{
564 if (err == -ENOENT) {
565 /* no trace? */
566 err = 0;
567 if (!req->r_reply_info.head->is_dentry) {
568 dout("ENOENT and no trace, dentry %p inode %p\n",
569 dentry, dentry->d_inode);
570 if (dentry->d_inode) {
571 d_drop(dentry);
572 err = -ENOENT;
573 } else {
574 d_add(dentry, NULL);
575 }
576 }
577 }
578 if (err)
579 dentry = ERR_PTR(err);
580 else if (dentry != req->r_dentry)
581 dentry = dget(req->r_dentry); /* we got spliced */
582 else
583 dentry = NULL;
584 return dentry;
585}
586
587static int is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
588{
589 return ceph_ino(inode) == CEPH_INO_ROOT &&
590 strncmp(dentry->d_name.name, ".ceph", 5) == 0;
591}
592
593/*
594 * Look up a single dir entry. If there is a lookup intent, inform
595 * the MDS so that it gets our 'caps wanted' value in a single op.
596 */
597static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
598 unsigned int flags)
599{
600 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
601 struct ceph_mds_client *mdsc = fsc->mdsc;
602 struct ceph_mds_request *req;
603 int op;
604 int err;
605
606 dout("lookup %p dentry %p '%.*s'\n",
607 dir, dentry, dentry->d_name.len, dentry->d_name.name);
608
609 if (dentry->d_name.len > NAME_MAX)
610 return ERR_PTR(-ENAMETOOLONG);
611
612 err = ceph_init_dentry(dentry);
613 if (err < 0)
614 return ERR_PTR(err);
615
616 /* can we conclude ENOENT locally? */
617 if (dentry->d_inode == NULL) {
618 struct ceph_inode_info *ci = ceph_inode(dir);
619 struct ceph_dentry_info *di = ceph_dentry(dentry);
620
621 spin_lock(&ci->i_ceph_lock);
622 dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags);
623 if (strncmp(dentry->d_name.name,
624 fsc->mount_options->snapdir_name,
625 dentry->d_name.len) &&
626 !is_root_ceph_dentry(dir, dentry) &&
627 __ceph_dir_is_complete(ci) &&
628 (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
629 spin_unlock(&ci->i_ceph_lock);
630 dout(" dir %p complete, -ENOENT\n", dir);
631 d_add(dentry, NULL);
632 di->lease_shared_gen = ci->i_shared_gen;
633 return NULL;
634 }
635 spin_unlock(&ci->i_ceph_lock);
636 }
637
638 op = ceph_snap(dir) == CEPH_SNAPDIR ?
639 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
640 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
641 if (IS_ERR(req))
642 return ERR_CAST(req);
643 req->r_dentry = dget(dentry);
644 req->r_num_caps = 2;
645 /* we only need inode linkage */
646 req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
647 req->r_locked_dir = dir;
648 err = ceph_mdsc_do_request(mdsc, NULL, req);
649 err = ceph_handle_snapdir(req, dentry, err);
650 dentry = ceph_finish_lookup(req, dentry, err);
651 ceph_mdsc_put_request(req); /* will dput(dentry) */
652 dout("lookup result=%p\n", dentry);
653 return dentry;
654}
655
656/*
657 * If we do a create but get no trace back from the MDS, follow up with
658 * a lookup (the VFS expects us to link up the provided dentry).
659 */
660int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
661{
662 struct dentry *result = ceph_lookup(dir, dentry, 0);
663
664 if (result && !IS_ERR(result)) {
665 /*
666 * We created the item, then did a lookup, and found
667 * it was already linked to another inode we already
668 * had in our cache (and thus got spliced). Link our
669 * dentry to that inode, but don't hash it, just in
670 * case the VFS wants to dereference it.
671 */
672 BUG_ON(!result->d_inode);
673 d_instantiate(dentry, result->d_inode);
674 return 0;
675 }
676 return PTR_ERR(result);
677}
678
679static int ceph_mknod(struct inode *dir, struct dentry *dentry,
680 umode_t mode, dev_t rdev)
681{
682 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
683 struct ceph_mds_client *mdsc = fsc->mdsc;
684 struct ceph_mds_request *req;
685 int err;
686
687 if (ceph_snap(dir) != CEPH_NOSNAP)
688 return -EROFS;
689
690 dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
691 dir, dentry, mode, rdev);
692 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
693 if (IS_ERR(req)) {
694 d_drop(dentry);
695 return PTR_ERR(req);
696 }
697 req->r_dentry = dget(dentry);
698 req->r_num_caps = 2;
699 req->r_locked_dir = dir;
700 req->r_args.mknod.mode = cpu_to_le32(mode);
701 req->r_args.mknod.rdev = cpu_to_le32(rdev);
702 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
703 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
704 err = ceph_mdsc_do_request(mdsc, dir, req);
705 if (!err && !req->r_reply_info.head->is_dentry)
706 err = ceph_handle_notrace_create(dir, dentry);
707 ceph_mdsc_put_request(req);
708
709 if (!err)
710 ceph_init_acl(dentry, dentry->d_inode, dir);
711 else
712 d_drop(dentry);
713 return err;
714}
715
716static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
717 bool excl)
718{
719 return ceph_mknod(dir, dentry, mode, 0);
720}
721
722static int ceph_symlink(struct inode *dir, struct dentry *dentry,
723 const char *dest)
724{
725 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
726 struct ceph_mds_client *mdsc = fsc->mdsc;
727 struct ceph_mds_request *req;
728 int err;
729
730 if (ceph_snap(dir) != CEPH_NOSNAP)
731 return -EROFS;
732
733 dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
734 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
735 if (IS_ERR(req)) {
736 d_drop(dentry);
737 return PTR_ERR(req);
738 }
739 req->r_dentry = dget(dentry);
740 req->r_num_caps = 2;
741 req->r_path2 = kstrdup(dest, GFP_NOFS);
742 req->r_locked_dir = dir;
743 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
744 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
745 err = ceph_mdsc_do_request(mdsc, dir, req);
746 if (!err && !req->r_reply_info.head->is_dentry)
747 err = ceph_handle_notrace_create(dir, dentry);
748 ceph_mdsc_put_request(req);
749 if (!err)
750 ceph_init_acl(dentry, dentry->d_inode, dir);
751 else
752 d_drop(dentry);
753 return err;
754}
755
756static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
757{
758 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
759 struct ceph_mds_client *mdsc = fsc->mdsc;
760 struct ceph_mds_request *req;
761 int err = -EROFS;
762 int op;
763
764 if (ceph_snap(dir) == CEPH_SNAPDIR) {
765 /* mkdir .snap/foo is a MKSNAP */
766 op = CEPH_MDS_OP_MKSNAP;
767 dout("mksnap dir %p snap '%.*s' dn %p\n", dir,
768 dentry->d_name.len, dentry->d_name.name, dentry);
769 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
770 dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
771 op = CEPH_MDS_OP_MKDIR;
772 } else {
773 goto out;
774 }
775 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
776 if (IS_ERR(req)) {
777 err = PTR_ERR(req);
778 goto out;
779 }
780
781 req->r_dentry = dget(dentry);
782 req->r_num_caps = 2;
783 req->r_locked_dir = dir;
784 req->r_args.mkdir.mode = cpu_to_le32(mode);
785 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
786 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
787 err = ceph_mdsc_do_request(mdsc, dir, req);
788 if (!err && !req->r_reply_info.head->is_dentry)
789 err = ceph_handle_notrace_create(dir, dentry);
790 ceph_mdsc_put_request(req);
791out:
792 if (!err)
793 ceph_init_acl(dentry, dentry->d_inode, dir);
794 else
795 d_drop(dentry);
796 return err;
797}
798
799static int ceph_link(struct dentry *old_dentry, struct inode *dir,
800 struct dentry *dentry)
801{
802 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
803 struct ceph_mds_client *mdsc = fsc->mdsc;
804 struct ceph_mds_request *req;
805 int err;
806
807 if (ceph_snap(dir) != CEPH_NOSNAP)
808 return -EROFS;
809
810 dout("link in dir %p old_dentry %p dentry %p\n", dir,
811 old_dentry, dentry);
812 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
813 if (IS_ERR(req)) {
814 d_drop(dentry);
815 return PTR_ERR(req);
816 }
817 req->r_dentry = dget(dentry);
818 req->r_num_caps = 2;
819 req->r_old_dentry = dget(old_dentry);
820 req->r_locked_dir = dir;
821 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
822 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
823 /* release LINK_SHARED on source inode (mds will lock it) */
824 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
825 err = ceph_mdsc_do_request(mdsc, dir, req);
826 if (err) {
827 d_drop(dentry);
828 } else if (!req->r_reply_info.head->is_dentry) {
829 ihold(old_dentry->d_inode);
830 d_instantiate(dentry, old_dentry->d_inode);
831 }
832 ceph_mdsc_put_request(req);
833 return err;
834}
835
836/*
837 * For a soon-to-be unlinked file, drop the AUTH_RDCACHE caps. If it
838 * looks like the link count will hit 0, drop any other caps (other
839 * than PIN) we don't specifically want (due to the file still being
840 * open).
841 */
842static int drop_caps_for_unlink(struct inode *inode)
843{
844 struct ceph_inode_info *ci = ceph_inode(inode);
845 int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
846
847 spin_lock(&ci->i_ceph_lock);
848 if (inode->i_nlink == 1) {
849 drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
850 ci->i_ceph_flags |= CEPH_I_NODELAY;
851 }
852 spin_unlock(&ci->i_ceph_lock);
853 return drop;
854}
855
856/*
857 * rmdir and unlink are differ only by the metadata op code
858 */
859static int ceph_unlink(struct inode *dir, struct dentry *dentry)
860{
861 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
862 struct ceph_mds_client *mdsc = fsc->mdsc;
863 struct inode *inode = dentry->d_inode;
864 struct ceph_mds_request *req;
865 int err = -EROFS;
866 int op;
867
868 if (ceph_snap(dir) == CEPH_SNAPDIR) {
869 /* rmdir .snap/foo is RMSNAP */
870 dout("rmsnap dir %p '%.*s' dn %p\n", dir, dentry->d_name.len,
871 dentry->d_name.name, dentry);
872 op = CEPH_MDS_OP_RMSNAP;
873 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
874 dout("unlink/rmdir dir %p dn %p inode %p\n",
875 dir, dentry, inode);
876 op = S_ISDIR(dentry->d_inode->i_mode) ?
877 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
878 } else
879 goto out;
880 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
881 if (IS_ERR(req)) {
882 err = PTR_ERR(req);
883 goto out;
884 }
885 req->r_dentry = dget(dentry);
886 req->r_num_caps = 2;
887 req->r_locked_dir = dir;
888 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
889 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
890 req->r_inode_drop = drop_caps_for_unlink(inode);
891 err = ceph_mdsc_do_request(mdsc, dir, req);
892 if (!err && !req->r_reply_info.head->is_dentry)
893 d_delete(dentry);
894 ceph_mdsc_put_request(req);
895out:
896 return err;
897}
898
899static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
900 struct inode *new_dir, struct dentry *new_dentry)
901{
902 struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
903 struct ceph_mds_client *mdsc = fsc->mdsc;
904 struct ceph_mds_request *req;
905 int err;
906
907 if (ceph_snap(old_dir) != ceph_snap(new_dir))
908 return -EXDEV;
909 if (ceph_snap(old_dir) != CEPH_NOSNAP ||
910 ceph_snap(new_dir) != CEPH_NOSNAP)
911 return -EROFS;
912 dout("rename dir %p dentry %p to dir %p dentry %p\n",
913 old_dir, old_dentry, new_dir, new_dentry);
914 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RENAME, USE_AUTH_MDS);
915 if (IS_ERR(req))
916 return PTR_ERR(req);
917 ihold(old_dir);
918 req->r_dentry = dget(new_dentry);
919 req->r_num_caps = 2;
920 req->r_old_dentry = dget(old_dentry);
921 req->r_old_dentry_dir = old_dir;
922 req->r_locked_dir = new_dir;
923 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
924 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
925 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
926 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
927 /* release LINK_RDCACHE on source inode (mds will lock it) */
928 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
929 if (new_dentry->d_inode)
930 req->r_inode_drop = drop_caps_for_unlink(new_dentry->d_inode);
931 err = ceph_mdsc_do_request(mdsc, old_dir, req);
932 if (!err && !req->r_reply_info.head->is_dentry) {
933 /*
934 * Normally d_move() is done by fill_trace (called by
935 * do_request, above). If there is no trace, we need
936 * to do it here.
937 */
938
939 d_move(old_dentry, new_dentry);
940
941 /* ensure target dentry is invalidated, despite
942 rehashing bug in vfs_rename_dir */
943 ceph_invalidate_dentry_lease(new_dentry);
944
945 /* d_move screws up sibling dentries' offsets */
946 ceph_dir_clear_complete(old_dir);
947 ceph_dir_clear_complete(new_dir);
948
949 }
950 ceph_mdsc_put_request(req);
951 return err;
952}
953
954/*
955 * Ensure a dentry lease will no longer revalidate.
956 */
957void ceph_invalidate_dentry_lease(struct dentry *dentry)
958{
959 spin_lock(&dentry->d_lock);
960 dentry->d_time = jiffies;
961 ceph_dentry(dentry)->lease_shared_gen = 0;
962 spin_unlock(&dentry->d_lock);
963}
964
965/*
966 * Check if dentry lease is valid. If not, delete the lease. Try to
967 * renew if the least is more than half up.
968 */
969static int dentry_lease_is_valid(struct dentry *dentry)
970{
971 struct ceph_dentry_info *di;
972 struct ceph_mds_session *s;
973 int valid = 0;
974 u32 gen;
975 unsigned long ttl;
976 struct ceph_mds_session *session = NULL;
977 struct inode *dir = NULL;
978 u32 seq = 0;
979
980 spin_lock(&dentry->d_lock);
981 di = ceph_dentry(dentry);
982 if (di->lease_session) {
983 s = di->lease_session;
984 spin_lock(&s->s_gen_ttl_lock);
985 gen = s->s_cap_gen;
986 ttl = s->s_cap_ttl;
987 spin_unlock(&s->s_gen_ttl_lock);
988
989 if (di->lease_gen == gen &&
990 time_before(jiffies, dentry->d_time) &&
991 time_before(jiffies, ttl)) {
992 valid = 1;
993 if (di->lease_renew_after &&
994 time_after(jiffies, di->lease_renew_after)) {
995 /* we should renew */
996 dir = dentry->d_parent->d_inode;
997 session = ceph_get_mds_session(s);
998 seq = di->lease_seq;
999 di->lease_renew_after = 0;
1000 di->lease_renew_from = jiffies;
1001 }
1002 }
1003 }
1004 spin_unlock(&dentry->d_lock);
1005
1006 if (session) {
1007 ceph_mdsc_lease_send_msg(session, dir, dentry,
1008 CEPH_MDS_LEASE_RENEW, seq);
1009 ceph_put_mds_session(session);
1010 }
1011 dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1012 return valid;
1013}
1014
1015/*
1016 * Check if directory-wide content lease/cap is valid.
1017 */
1018static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
1019{
1020 struct ceph_inode_info *ci = ceph_inode(dir);
1021 struct ceph_dentry_info *di = ceph_dentry(dentry);
1022 int valid = 0;
1023
1024 spin_lock(&ci->i_ceph_lock);
1025 if (ci->i_shared_gen == di->lease_shared_gen)
1026 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1027 spin_unlock(&ci->i_ceph_lock);
1028 dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
1029 dir, (unsigned)ci->i_shared_gen, dentry,
1030 (unsigned)di->lease_shared_gen, valid);
1031 return valid;
1032}
1033
1034/*
1035 * Check if cached dentry can be trusted.
1036 */
1037static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1038{
1039 int valid = 0;
1040 struct inode *dir;
1041
1042 if (flags & LOOKUP_RCU)
1043 return -ECHILD;
1044
1045 dout("d_revalidate %p '%.*s' inode %p offset %lld\n", dentry,
1046 dentry->d_name.len, dentry->d_name.name, dentry->d_inode,
1047 ceph_dentry(dentry)->offset);
1048
1049 dir = ceph_get_dentry_parent_inode(dentry);
1050
1051 /* always trust cached snapped dentries, snapdir dentry */
1052 if (ceph_snap(dir) != CEPH_NOSNAP) {
1053 dout("d_revalidate %p '%.*s' inode %p is SNAPPED\n", dentry,
1054 dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
1055 valid = 1;
1056 } else if (dentry->d_inode &&
1057 ceph_snap(dentry->d_inode) == CEPH_SNAPDIR) {
1058 valid = 1;
1059 } else if (dentry_lease_is_valid(dentry) ||
1060 dir_lease_is_valid(dir, dentry)) {
1061 if (dentry->d_inode)
1062 valid = ceph_is_any_caps(dentry->d_inode);
1063 else
1064 valid = 1;
1065 }
1066
1067 dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1068 if (valid) {
1069 ceph_dentry_lru_touch(dentry);
1070 } else {
1071 ceph_dir_clear_complete(dir);
1072 d_drop(dentry);
1073 }
1074 iput(dir);
1075 return valid;
1076}
1077
1078/*
1079 * Release our ceph_dentry_info.
1080 */
1081static void ceph_d_release(struct dentry *dentry)
1082{
1083 struct ceph_dentry_info *di = ceph_dentry(dentry);
1084
1085 dout("d_release %p\n", dentry);
1086 ceph_dentry_lru_del(dentry);
1087 if (di->lease_session)
1088 ceph_put_mds_session(di->lease_session);
1089 kmem_cache_free(ceph_dentry_cachep, di);
1090 dentry->d_fsdata = NULL;
1091}
1092
1093static int ceph_snapdir_d_revalidate(struct dentry *dentry,
1094 unsigned int flags)
1095{
1096 /*
1097 * Eventually, we'll want to revalidate snapped metadata
1098 * too... probably...
1099 */
1100 return 1;
1101}
1102
1103/*
1104 * When the VFS prunes a dentry from the cache, we need to clear the
1105 * complete flag on the parent directory.
1106 *
1107 * Called under dentry->d_lock.
1108 */
1109static void ceph_d_prune(struct dentry *dentry)
1110{
1111 dout("ceph_d_prune %p\n", dentry);
1112
1113 /* do we have a valid parent? */
1114 if (IS_ROOT(dentry))
1115 return;
1116
1117 /* if we are not hashed, we don't affect dir's completeness */
1118 if (d_unhashed(dentry))
1119 return;
1120
1121 /*
1122 * we hold d_lock, so d_parent is stable, and d_fsdata is never
1123 * cleared until d_release
1124 */
1125 ceph_dir_clear_complete(dentry->d_parent->d_inode);
1126}
1127
1128/*
1129 * read() on a dir. This weird interface hack only works if mounted
1130 * with '-o dirstat'.
1131 */
1132static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1133 loff_t *ppos)
1134{
1135 struct ceph_file_info *cf = file->private_data;
1136 struct inode *inode = file_inode(file);
1137 struct ceph_inode_info *ci = ceph_inode(inode);
1138 int left;
1139 const int bufsize = 1024;
1140
1141 if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1142 return -EISDIR;
1143
1144 if (!cf->dir_info) {
1145 cf->dir_info = kmalloc(bufsize, GFP_NOFS);
1146 if (!cf->dir_info)
1147 return -ENOMEM;
1148 cf->dir_info_len =
1149 snprintf(cf->dir_info, bufsize,
1150 "entries: %20lld\n"
1151 " files: %20lld\n"
1152 " subdirs: %20lld\n"
1153 "rentries: %20lld\n"
1154 " rfiles: %20lld\n"
1155 " rsubdirs: %20lld\n"
1156 "rbytes: %20lld\n"
1157 "rctime: %10ld.%09ld\n",
1158 ci->i_files + ci->i_subdirs,
1159 ci->i_files,
1160 ci->i_subdirs,
1161 ci->i_rfiles + ci->i_rsubdirs,
1162 ci->i_rfiles,
1163 ci->i_rsubdirs,
1164 ci->i_rbytes,
1165 (long)ci->i_rctime.tv_sec,
1166 (long)ci->i_rctime.tv_nsec);
1167 }
1168
1169 if (*ppos >= cf->dir_info_len)
1170 return 0;
1171 size = min_t(unsigned, size, cf->dir_info_len-*ppos);
1172 left = copy_to_user(buf, cf->dir_info + *ppos, size);
1173 if (left == size)
1174 return -EFAULT;
1175 *ppos += (size - left);
1176 return size - left;
1177}
1178
1179/*
1180 * an fsync() on a dir will wait for any uncommitted directory
1181 * operations to commit.
1182 */
1183static int ceph_dir_fsync(struct file *file, loff_t start, loff_t end,
1184 int datasync)
1185{
1186 struct inode *inode = file_inode(file);
1187 struct ceph_inode_info *ci = ceph_inode(inode);
1188 struct list_head *head = &ci->i_unsafe_dirops;
1189 struct ceph_mds_request *req;
1190 u64 last_tid;
1191 int ret = 0;
1192
1193 dout("dir_fsync %p\n", inode);
1194 ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1195 if (ret)
1196 return ret;
1197 mutex_lock(&inode->i_mutex);
1198
1199 spin_lock(&ci->i_unsafe_lock);
1200 if (list_empty(head))
1201 goto out;
1202
1203 req = list_entry(head->prev,
1204 struct ceph_mds_request, r_unsafe_dir_item);
1205 last_tid = req->r_tid;
1206
1207 do {
1208 ceph_mdsc_get_request(req);
1209 spin_unlock(&ci->i_unsafe_lock);
1210
1211 dout("dir_fsync %p wait on tid %llu (until %llu)\n",
1212 inode, req->r_tid, last_tid);
1213 if (req->r_timeout) {
1214 ret = wait_for_completion_timeout(
1215 &req->r_safe_completion, req->r_timeout);
1216 if (ret > 0)
1217 ret = 0;
1218 else if (ret == 0)
1219 ret = -EIO; /* timed out */
1220 } else {
1221 wait_for_completion(&req->r_safe_completion);
1222 }
1223 ceph_mdsc_put_request(req);
1224
1225 spin_lock(&ci->i_unsafe_lock);
1226 if (ret || list_empty(head))
1227 break;
1228 req = list_entry(head->next,
1229 struct ceph_mds_request, r_unsafe_dir_item);
1230 } while (req->r_tid < last_tid);
1231out:
1232 spin_unlock(&ci->i_unsafe_lock);
1233 mutex_unlock(&inode->i_mutex);
1234
1235 return ret;
1236}
1237
1238/*
1239 * We maintain a private dentry LRU.
1240 *
1241 * FIXME: this needs to be changed to a per-mds lru to be useful.
1242 */
1243void ceph_dentry_lru_add(struct dentry *dn)
1244{
1245 struct ceph_dentry_info *di = ceph_dentry(dn);
1246 struct ceph_mds_client *mdsc;
1247
1248 dout("dentry_lru_add %p %p '%.*s'\n", di, dn,
1249 dn->d_name.len, dn->d_name.name);
1250 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1251 spin_lock(&mdsc->dentry_lru_lock);
1252 list_add_tail(&di->lru, &mdsc->dentry_lru);
1253 mdsc->num_dentry++;
1254 spin_unlock(&mdsc->dentry_lru_lock);
1255}
1256
1257void ceph_dentry_lru_touch(struct dentry *dn)
1258{
1259 struct ceph_dentry_info *di = ceph_dentry(dn);
1260 struct ceph_mds_client *mdsc;
1261
1262 dout("dentry_lru_touch %p %p '%.*s' (offset %lld)\n", di, dn,
1263 dn->d_name.len, dn->d_name.name, di->offset);
1264 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1265 spin_lock(&mdsc->dentry_lru_lock);
1266 list_move_tail(&di->lru, &mdsc->dentry_lru);
1267 spin_unlock(&mdsc->dentry_lru_lock);
1268}
1269
1270void ceph_dentry_lru_del(struct dentry *dn)
1271{
1272 struct ceph_dentry_info *di = ceph_dentry(dn);
1273 struct ceph_mds_client *mdsc;
1274
1275 dout("dentry_lru_del %p %p '%.*s'\n", di, dn,
1276 dn->d_name.len, dn->d_name.name);
1277 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1278 spin_lock(&mdsc->dentry_lru_lock);
1279 list_del_init(&di->lru);
1280 mdsc->num_dentry--;
1281 spin_unlock(&mdsc->dentry_lru_lock);
1282}
1283
1284/*
1285 * Return name hash for a given dentry. This is dependent on
1286 * the parent directory's hash function.
1287 */
1288unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1289{
1290 struct ceph_inode_info *dci = ceph_inode(dir);
1291
1292 switch (dci->i_dir_layout.dl_dir_hash) {
1293 case 0: /* for backward compat */
1294 case CEPH_STR_HASH_LINUX:
1295 return dn->d_name.hash;
1296
1297 default:
1298 return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
1299 dn->d_name.name, dn->d_name.len);
1300 }
1301}
1302
1303const struct file_operations ceph_dir_fops = {
1304 .read = ceph_read_dir,
1305 .iterate = ceph_readdir,
1306 .llseek = ceph_dir_llseek,
1307 .open = ceph_open,
1308 .release = ceph_release,
1309 .unlocked_ioctl = ceph_ioctl,
1310 .fsync = ceph_dir_fsync,
1311};
1312
1313const struct inode_operations ceph_dir_iops = {
1314 .lookup = ceph_lookup,
1315 .permission = ceph_permission,
1316 .getattr = ceph_getattr,
1317 .setattr = ceph_setattr,
1318 .setxattr = ceph_setxattr,
1319 .getxattr = ceph_getxattr,
1320 .listxattr = ceph_listxattr,
1321 .removexattr = ceph_removexattr,
1322 .get_acl = ceph_get_acl,
1323 .set_acl = ceph_set_acl,
1324 .mknod = ceph_mknod,
1325 .symlink = ceph_symlink,
1326 .mkdir = ceph_mkdir,
1327 .link = ceph_link,
1328 .unlink = ceph_unlink,
1329 .rmdir = ceph_unlink,
1330 .rename = ceph_rename,
1331 .create = ceph_create,
1332 .atomic_open = ceph_atomic_open,
1333};
1334
1335const struct dentry_operations ceph_dentry_ops = {
1336 .d_revalidate = ceph_d_revalidate,
1337 .d_release = ceph_d_release,
1338 .d_prune = ceph_d_prune,
1339};
1340
1341const struct dentry_operations ceph_snapdir_dentry_ops = {
1342 .d_revalidate = ceph_snapdir_d_revalidate,
1343 .d_release = ceph_d_release,
1344};
1345
1346const struct dentry_operations ceph_snap_dentry_ops = {
1347 .d_release = ceph_d_release,
1348 .d_prune = ceph_d_prune,
1349};
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
30const struct dentry_operations ceph_dentry_ops;
31
32/*
33 * Initialize ceph dentry state.
34 */
35static 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))
62loff_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
70static bool is_hash_order(loff_t p)
71{
72 return (p & HASH_ORDER) == HASH_ORDER;
73}
74
75static unsigned fpos_frag(loff_t p)
76{
77 return p >> OFFSET_BITS;
78}
79
80static unsigned fpos_hash(loff_t p)
81{
82 return ceph_frag_value(fpos_frag(p));
83}
84
85static unsigned fpos_off(loff_t p)
86{
87 return p & OFFSET_MASK;
88}
89
90static 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 */
104static 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
120static 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 */
174static 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 }
270out:
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
289static 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
299static 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 */
351more:
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
578static 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 */
596static 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
616static 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 }
653out:
654 inode_unlock(inode);
655 return retval;
656}
657
658/*
659 * Handle lookups for the hidden .snap directory.
660 */
661int 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 */
693struct 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
719static 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 */
729static 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 */
795int 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
818static 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 return -EDQUOT;
832
833 err = ceph_pre_init_acls(dir, &mode, &acls);
834 if (err < 0)
835 return err;
836
837 dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
838 dir, dentry, mode, rdev);
839 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
840 if (IS_ERR(req)) {
841 err = PTR_ERR(req);
842 goto out;
843 }
844 req->r_dentry = dget(dentry);
845 req->r_num_caps = 2;
846 req->r_parent = dir;
847 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
848 req->r_args.mknod.mode = cpu_to_le32(mode);
849 req->r_args.mknod.rdev = cpu_to_le32(rdev);
850 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
851 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
852 if (acls.pagelist) {
853 req->r_pagelist = acls.pagelist;
854 acls.pagelist = NULL;
855 }
856 err = ceph_mdsc_do_request(mdsc, dir, req);
857 if (!err && !req->r_reply_info.head->is_dentry)
858 err = ceph_handle_notrace_create(dir, dentry);
859 ceph_mdsc_put_request(req);
860out:
861 if (!err)
862 ceph_init_inode_acls(d_inode(dentry), &acls);
863 else
864 d_drop(dentry);
865 ceph_release_acls_info(&acls);
866 return err;
867}
868
869static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
870 bool excl)
871{
872 return ceph_mknod(dir, dentry, mode, 0);
873}
874
875static int ceph_symlink(struct inode *dir, struct dentry *dentry,
876 const char *dest)
877{
878 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
879 struct ceph_mds_client *mdsc = fsc->mdsc;
880 struct ceph_mds_request *req;
881 int err;
882
883 if (ceph_snap(dir) != CEPH_NOSNAP)
884 return -EROFS;
885
886 if (ceph_quota_is_max_files_exceeded(dir))
887 return -EDQUOT;
888
889 dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
890 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
891 if (IS_ERR(req)) {
892 err = PTR_ERR(req);
893 goto out;
894 }
895 req->r_path2 = kstrdup(dest, GFP_KERNEL);
896 if (!req->r_path2) {
897 err = -ENOMEM;
898 ceph_mdsc_put_request(req);
899 goto out;
900 }
901 req->r_parent = dir;
902 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
903 req->r_dentry = dget(dentry);
904 req->r_num_caps = 2;
905 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
906 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
907 err = ceph_mdsc_do_request(mdsc, dir, req);
908 if (!err && !req->r_reply_info.head->is_dentry)
909 err = ceph_handle_notrace_create(dir, dentry);
910 ceph_mdsc_put_request(req);
911out:
912 if (err)
913 d_drop(dentry);
914 return err;
915}
916
917static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
918{
919 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
920 struct ceph_mds_client *mdsc = fsc->mdsc;
921 struct ceph_mds_request *req;
922 struct ceph_acls_info acls = {};
923 int err = -EROFS;
924 int op;
925
926 if (ceph_snap(dir) == CEPH_SNAPDIR) {
927 /* mkdir .snap/foo is a MKSNAP */
928 op = CEPH_MDS_OP_MKSNAP;
929 dout("mksnap dir %p snap '%pd' dn %p\n", dir,
930 dentry, dentry);
931 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
932 dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
933 op = CEPH_MDS_OP_MKDIR;
934 } else {
935 goto out;
936 }
937
938 if (op == CEPH_MDS_OP_MKDIR &&
939 ceph_quota_is_max_files_exceeded(dir)) {
940 err = -EDQUOT;
941 goto out;
942 }
943
944 mode |= S_IFDIR;
945 err = ceph_pre_init_acls(dir, &mode, &acls);
946 if (err < 0)
947 goto out;
948
949 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
950 if (IS_ERR(req)) {
951 err = PTR_ERR(req);
952 goto out;
953 }
954
955 req->r_dentry = dget(dentry);
956 req->r_num_caps = 2;
957 req->r_parent = dir;
958 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
959 req->r_args.mkdir.mode = cpu_to_le32(mode);
960 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
961 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
962 if (acls.pagelist) {
963 req->r_pagelist = acls.pagelist;
964 acls.pagelist = NULL;
965 }
966 err = ceph_mdsc_do_request(mdsc, dir, req);
967 if (!err &&
968 !req->r_reply_info.head->is_target &&
969 !req->r_reply_info.head->is_dentry)
970 err = ceph_handle_notrace_create(dir, dentry);
971 ceph_mdsc_put_request(req);
972out:
973 if (!err)
974 ceph_init_inode_acls(d_inode(dentry), &acls);
975 else
976 d_drop(dentry);
977 ceph_release_acls_info(&acls);
978 return err;
979}
980
981static int ceph_link(struct dentry *old_dentry, struct inode *dir,
982 struct dentry *dentry)
983{
984 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
985 struct ceph_mds_client *mdsc = fsc->mdsc;
986 struct ceph_mds_request *req;
987 int err;
988
989 if (ceph_snap(dir) != CEPH_NOSNAP)
990 return -EROFS;
991
992 dout("link in dir %p old_dentry %p dentry %p\n", dir,
993 old_dentry, dentry);
994 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
995 if (IS_ERR(req)) {
996 d_drop(dentry);
997 return PTR_ERR(req);
998 }
999 req->r_dentry = dget(dentry);
1000 req->r_num_caps = 2;
1001 req->r_old_dentry = dget(old_dentry);
1002 req->r_parent = dir;
1003 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1004 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1005 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1006 /* release LINK_SHARED on source inode (mds will lock it) */
1007 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1008 err = ceph_mdsc_do_request(mdsc, dir, req);
1009 if (err) {
1010 d_drop(dentry);
1011 } else if (!req->r_reply_info.head->is_dentry) {
1012 ihold(d_inode(old_dentry));
1013 d_instantiate(dentry, d_inode(old_dentry));
1014 }
1015 ceph_mdsc_put_request(req);
1016 return err;
1017}
1018
1019/*
1020 * rmdir and unlink are differ only by the metadata op code
1021 */
1022static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1023{
1024 struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
1025 struct ceph_mds_client *mdsc = fsc->mdsc;
1026 struct inode *inode = d_inode(dentry);
1027 struct ceph_mds_request *req;
1028 int err = -EROFS;
1029 int op;
1030
1031 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1032 /* rmdir .snap/foo is RMSNAP */
1033 dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry);
1034 op = CEPH_MDS_OP_RMSNAP;
1035 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1036 dout("unlink/rmdir dir %p dn %p inode %p\n",
1037 dir, dentry, inode);
1038 op = d_is_dir(dentry) ?
1039 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1040 } else
1041 goto out;
1042 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1043 if (IS_ERR(req)) {
1044 err = PTR_ERR(req);
1045 goto out;
1046 }
1047 req->r_dentry = dget(dentry);
1048 req->r_num_caps = 2;
1049 req->r_parent = dir;
1050 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1051 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1052 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1053 req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1054 err = ceph_mdsc_do_request(mdsc, dir, req);
1055 if (!err && !req->r_reply_info.head->is_dentry)
1056 d_delete(dentry);
1057 ceph_mdsc_put_request(req);
1058out:
1059 return err;
1060}
1061
1062static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
1063 struct inode *new_dir, struct dentry *new_dentry,
1064 unsigned int flags)
1065{
1066 struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
1067 struct ceph_mds_client *mdsc = fsc->mdsc;
1068 struct ceph_mds_request *req;
1069 int op = CEPH_MDS_OP_RENAME;
1070 int err;
1071
1072 if (flags)
1073 return -EINVAL;
1074
1075 if (ceph_snap(old_dir) != ceph_snap(new_dir))
1076 return -EXDEV;
1077 if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1078 if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1079 op = CEPH_MDS_OP_RENAMESNAP;
1080 else
1081 return -EROFS;
1082 }
1083 /* don't allow cross-quota renames */
1084 if ((old_dir != new_dir) &&
1085 (!ceph_quota_is_same_realm(old_dir, new_dir)))
1086 return -EXDEV;
1087
1088 dout("rename dir %p dentry %p to dir %p dentry %p\n",
1089 old_dir, old_dentry, new_dir, new_dentry);
1090 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1091 if (IS_ERR(req))
1092 return PTR_ERR(req);
1093 ihold(old_dir);
1094 req->r_dentry = dget(new_dentry);
1095 req->r_num_caps = 2;
1096 req->r_old_dentry = dget(old_dentry);
1097 req->r_old_dentry_dir = old_dir;
1098 req->r_parent = new_dir;
1099 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1100 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
1101 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1102 req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1103 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1104 /* release LINK_RDCACHE on source inode (mds will lock it) */
1105 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1106 if (d_really_is_positive(new_dentry)) {
1107 req->r_inode_drop =
1108 ceph_drop_caps_for_unlink(d_inode(new_dentry));
1109 }
1110 err = ceph_mdsc_do_request(mdsc, old_dir, req);
1111 if (!err && !req->r_reply_info.head->is_dentry) {
1112 /*
1113 * Normally d_move() is done by fill_trace (called by
1114 * do_request, above). If there is no trace, we need
1115 * to do it here.
1116 */
1117 d_move(old_dentry, new_dentry);
1118 }
1119 ceph_mdsc_put_request(req);
1120 return err;
1121}
1122
1123/*
1124 * Ensure a dentry lease will no longer revalidate.
1125 */
1126void ceph_invalidate_dentry_lease(struct dentry *dentry)
1127{
1128 spin_lock(&dentry->d_lock);
1129 ceph_dentry(dentry)->time = jiffies;
1130 ceph_dentry(dentry)->lease_shared_gen = 0;
1131 spin_unlock(&dentry->d_lock);
1132}
1133
1134/*
1135 * Check if dentry lease is valid. If not, delete the lease. Try to
1136 * renew if the least is more than half up.
1137 */
1138static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags,
1139 struct inode *dir)
1140{
1141 struct ceph_dentry_info *di;
1142 struct ceph_mds_session *s;
1143 int valid = 0;
1144 u32 gen;
1145 unsigned long ttl;
1146 struct ceph_mds_session *session = NULL;
1147 u32 seq = 0;
1148
1149 spin_lock(&dentry->d_lock);
1150 di = ceph_dentry(dentry);
1151 if (di && di->lease_session) {
1152 s = di->lease_session;
1153 spin_lock(&s->s_gen_ttl_lock);
1154 gen = s->s_cap_gen;
1155 ttl = s->s_cap_ttl;
1156 spin_unlock(&s->s_gen_ttl_lock);
1157
1158 if (di->lease_gen == gen &&
1159 time_before(jiffies, di->time) &&
1160 time_before(jiffies, ttl)) {
1161 valid = 1;
1162 if (di->lease_renew_after &&
1163 time_after(jiffies, di->lease_renew_after)) {
1164 /*
1165 * We should renew. If we're in RCU walk mode
1166 * though, we can't do that so just return
1167 * -ECHILD.
1168 */
1169 if (flags & LOOKUP_RCU) {
1170 valid = -ECHILD;
1171 } else {
1172 session = ceph_get_mds_session(s);
1173 seq = di->lease_seq;
1174 di->lease_renew_after = 0;
1175 di->lease_renew_from = jiffies;
1176 }
1177 }
1178 }
1179 }
1180 spin_unlock(&dentry->d_lock);
1181
1182 if (session) {
1183 ceph_mdsc_lease_send_msg(session, dir, dentry,
1184 CEPH_MDS_LEASE_RENEW, seq);
1185 ceph_put_mds_session(session);
1186 }
1187 dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1188 return valid;
1189}
1190
1191/*
1192 * Check if directory-wide content lease/cap is valid.
1193 */
1194static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
1195{
1196 struct ceph_inode_info *ci = ceph_inode(dir);
1197 struct ceph_dentry_info *di = ceph_dentry(dentry);
1198 int valid = 0;
1199
1200 spin_lock(&ci->i_ceph_lock);
1201 if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen)
1202 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1203 spin_unlock(&ci->i_ceph_lock);
1204 dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
1205 dir, (unsigned)atomic_read(&ci->i_shared_gen),
1206 dentry, (unsigned)di->lease_shared_gen, valid);
1207 return valid;
1208}
1209
1210/*
1211 * Check if cached dentry can be trusted.
1212 */
1213static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1214{
1215 int valid = 0;
1216 struct dentry *parent;
1217 struct inode *dir;
1218
1219 if (flags & LOOKUP_RCU) {
1220 parent = READ_ONCE(dentry->d_parent);
1221 dir = d_inode_rcu(parent);
1222 if (!dir)
1223 return -ECHILD;
1224 } else {
1225 parent = dget_parent(dentry);
1226 dir = d_inode(parent);
1227 }
1228
1229 dout("d_revalidate %p '%pd' inode %p offset %lld\n", dentry,
1230 dentry, d_inode(dentry), ceph_dentry(dentry)->offset);
1231
1232 /* always trust cached snapped dentries, snapdir dentry */
1233 if (ceph_snap(dir) != CEPH_NOSNAP) {
1234 dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
1235 dentry, d_inode(dentry));
1236 valid = 1;
1237 } else if (d_really_is_positive(dentry) &&
1238 ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
1239 valid = 1;
1240 } else {
1241 valid = dentry_lease_is_valid(dentry, flags, dir);
1242 if (valid == -ECHILD)
1243 return valid;
1244 if (valid || dir_lease_is_valid(dir, dentry)) {
1245 if (d_really_is_positive(dentry))
1246 valid = ceph_is_any_caps(d_inode(dentry));
1247 else
1248 valid = 1;
1249 }
1250 }
1251
1252 if (!valid) {
1253 struct ceph_mds_client *mdsc =
1254 ceph_sb_to_client(dir->i_sb)->mdsc;
1255 struct ceph_mds_request *req;
1256 int op, err;
1257 u32 mask;
1258
1259 if (flags & LOOKUP_RCU)
1260 return -ECHILD;
1261
1262 op = ceph_snap(dir) == CEPH_SNAPDIR ?
1263 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
1264 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
1265 if (!IS_ERR(req)) {
1266 req->r_dentry = dget(dentry);
1267 req->r_num_caps = 2;
1268 req->r_parent = dir;
1269
1270 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
1271 if (ceph_security_xattr_wanted(dir))
1272 mask |= CEPH_CAP_XATTR_SHARED;
1273 req->r_args.getattr.mask = cpu_to_le32(mask);
1274
1275 err = ceph_mdsc_do_request(mdsc, NULL, req);
1276 switch (err) {
1277 case 0:
1278 if (d_really_is_positive(dentry) &&
1279 d_inode(dentry) == req->r_target_inode)
1280 valid = 1;
1281 break;
1282 case -ENOENT:
1283 if (d_really_is_negative(dentry))
1284 valid = 1;
1285 /* Fallthrough */
1286 default:
1287 break;
1288 }
1289 ceph_mdsc_put_request(req);
1290 dout("d_revalidate %p lookup result=%d\n",
1291 dentry, err);
1292 }
1293 }
1294
1295 dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1296 if (valid) {
1297 ceph_dentry_lru_touch(dentry);
1298 } else {
1299 ceph_dir_clear_complete(dir);
1300 }
1301
1302 if (!(flags & LOOKUP_RCU))
1303 dput(parent);
1304 return valid;
1305}
1306
1307/*
1308 * Release our ceph_dentry_info.
1309 */
1310static void ceph_d_release(struct dentry *dentry)
1311{
1312 struct ceph_dentry_info *di = ceph_dentry(dentry);
1313
1314 dout("d_release %p\n", dentry);
1315 ceph_dentry_lru_del(dentry);
1316
1317 spin_lock(&dentry->d_lock);
1318 dentry->d_fsdata = NULL;
1319 spin_unlock(&dentry->d_lock);
1320
1321 if (di->lease_session)
1322 ceph_put_mds_session(di->lease_session);
1323 kmem_cache_free(ceph_dentry_cachep, di);
1324}
1325
1326/*
1327 * When the VFS prunes a dentry from the cache, we need to clear the
1328 * complete flag on the parent directory.
1329 *
1330 * Called under dentry->d_lock.
1331 */
1332static void ceph_d_prune(struct dentry *dentry)
1333{
1334 struct ceph_inode_info *dir_ci;
1335 struct ceph_dentry_info *di;
1336
1337 dout("ceph_d_prune %pd %p\n", dentry, dentry);
1338
1339 /* do we have a valid parent? */
1340 if (IS_ROOT(dentry))
1341 return;
1342
1343 /* we hold d_lock, so d_parent is stable */
1344 dir_ci = ceph_inode(d_inode(dentry->d_parent));
1345 if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
1346 return;
1347
1348 /* who calls d_delete() should also disable dcache readdir */
1349 if (d_really_is_negative(dentry))
1350 return;
1351
1352 /* d_fsdata does not get cleared until d_release */
1353 if (!d_unhashed(dentry)) {
1354 __ceph_dir_clear_complete(dir_ci);
1355 return;
1356 }
1357
1358 /* Disable dcache readdir just in case that someone called d_drop()
1359 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
1360 * properly (dcache readdir is still enabled) */
1361 di = ceph_dentry(dentry);
1362 if (di->offset > 0 &&
1363 di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
1364 __ceph_dir_clear_ordered(dir_ci);
1365}
1366
1367/*
1368 * read() on a dir. This weird interface hack only works if mounted
1369 * with '-o dirstat'.
1370 */
1371static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1372 loff_t *ppos)
1373{
1374 struct ceph_dir_file_info *dfi = file->private_data;
1375 struct inode *inode = file_inode(file);
1376 struct ceph_inode_info *ci = ceph_inode(inode);
1377 int left;
1378 const int bufsize = 1024;
1379
1380 if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1381 return -EISDIR;
1382
1383 if (!dfi->dir_info) {
1384 dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
1385 if (!dfi->dir_info)
1386 return -ENOMEM;
1387 dfi->dir_info_len =
1388 snprintf(dfi->dir_info, bufsize,
1389 "entries: %20lld\n"
1390 " files: %20lld\n"
1391 " subdirs: %20lld\n"
1392 "rentries: %20lld\n"
1393 " rfiles: %20lld\n"
1394 " rsubdirs: %20lld\n"
1395 "rbytes: %20lld\n"
1396 "rctime: %10ld.%09ld\n",
1397 ci->i_files + ci->i_subdirs,
1398 ci->i_files,
1399 ci->i_subdirs,
1400 ci->i_rfiles + ci->i_rsubdirs,
1401 ci->i_rfiles,
1402 ci->i_rsubdirs,
1403 ci->i_rbytes,
1404 (long)ci->i_rctime.tv_sec,
1405 (long)ci->i_rctime.tv_nsec);
1406 }
1407
1408 if (*ppos >= dfi->dir_info_len)
1409 return 0;
1410 size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
1411 left = copy_to_user(buf, dfi->dir_info + *ppos, size);
1412 if (left == size)
1413 return -EFAULT;
1414 *ppos += (size - left);
1415 return size - left;
1416}
1417
1418/*
1419 * We maintain a private dentry LRU.
1420 *
1421 * FIXME: this needs to be changed to a per-mds lru to be useful.
1422 */
1423void ceph_dentry_lru_add(struct dentry *dn)
1424{
1425 struct ceph_dentry_info *di = ceph_dentry(dn);
1426 struct ceph_mds_client *mdsc;
1427
1428 dout("dentry_lru_add %p %p '%pd'\n", di, dn, dn);
1429 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1430 spin_lock(&mdsc->dentry_lru_lock);
1431 list_add_tail(&di->lru, &mdsc->dentry_lru);
1432 mdsc->num_dentry++;
1433 spin_unlock(&mdsc->dentry_lru_lock);
1434}
1435
1436void ceph_dentry_lru_touch(struct dentry *dn)
1437{
1438 struct ceph_dentry_info *di = ceph_dentry(dn);
1439 struct ceph_mds_client *mdsc;
1440
1441 dout("dentry_lru_touch %p %p '%pd' (offset %lld)\n", di, dn, dn,
1442 di->offset);
1443 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1444 spin_lock(&mdsc->dentry_lru_lock);
1445 list_move_tail(&di->lru, &mdsc->dentry_lru);
1446 spin_unlock(&mdsc->dentry_lru_lock);
1447}
1448
1449void ceph_dentry_lru_del(struct dentry *dn)
1450{
1451 struct ceph_dentry_info *di = ceph_dentry(dn);
1452 struct ceph_mds_client *mdsc;
1453
1454 dout("dentry_lru_del %p %p '%pd'\n", di, dn, dn);
1455 mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1456 spin_lock(&mdsc->dentry_lru_lock);
1457 list_del_init(&di->lru);
1458 mdsc->num_dentry--;
1459 spin_unlock(&mdsc->dentry_lru_lock);
1460}
1461
1462/*
1463 * Return name hash for a given dentry. This is dependent on
1464 * the parent directory's hash function.
1465 */
1466unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1467{
1468 struct ceph_inode_info *dci = ceph_inode(dir);
1469
1470 switch (dci->i_dir_layout.dl_dir_hash) {
1471 case 0: /* for backward compat */
1472 case CEPH_STR_HASH_LINUX:
1473 return dn->d_name.hash;
1474
1475 default:
1476 return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
1477 dn->d_name.name, dn->d_name.len);
1478 }
1479}
1480
1481const struct file_operations ceph_dir_fops = {
1482 .read = ceph_read_dir,
1483 .iterate = ceph_readdir,
1484 .llseek = ceph_dir_llseek,
1485 .open = ceph_open,
1486 .release = ceph_release,
1487 .unlocked_ioctl = ceph_ioctl,
1488 .fsync = ceph_fsync,
1489};
1490
1491const struct file_operations ceph_snapdir_fops = {
1492 .iterate = ceph_readdir,
1493 .llseek = ceph_dir_llseek,
1494 .open = ceph_open,
1495 .release = ceph_release,
1496};
1497
1498const struct inode_operations ceph_dir_iops = {
1499 .lookup = ceph_lookup,
1500 .permission = ceph_permission,
1501 .getattr = ceph_getattr,
1502 .setattr = ceph_setattr,
1503 .listxattr = ceph_listxattr,
1504 .get_acl = ceph_get_acl,
1505 .set_acl = ceph_set_acl,
1506 .mknod = ceph_mknod,
1507 .symlink = ceph_symlink,
1508 .mkdir = ceph_mkdir,
1509 .link = ceph_link,
1510 .unlink = ceph_unlink,
1511 .rmdir = ceph_unlink,
1512 .rename = ceph_rename,
1513 .create = ceph_create,
1514 .atomic_open = ceph_atomic_open,
1515};
1516
1517const struct inode_operations ceph_snapdir_iops = {
1518 .lookup = ceph_lookup,
1519 .permission = ceph_permission,
1520 .getattr = ceph_getattr,
1521 .mkdir = ceph_mkdir,
1522 .rmdir = ceph_unlink,
1523 .rename = ceph_rename,
1524};
1525
1526const struct dentry_operations ceph_dentry_ops = {
1527 .d_revalidate = ceph_d_revalidate,
1528 .d_release = ceph_d_release,
1529 .d_prune = ceph_d_prune,
1530 .d_init = ceph_d_init,
1531};