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