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 #include "crypto.h"
13
14 /*
15 * Directory operations: readdir, lookup, create, link, unlink,
16 * rename, etc.
17 */
18
19 /*
20 * Ceph MDS operations are specified in terms of a base ino and
21 * relative path. Thus, the client can specify an operation on a
22 * specific inode (e.g., a getattr due to fstat(2)), or as a path
23 * relative to, say, the root directory.
24 *
25 * Normally, we limit ourselves to strict inode ops (no path component)
26 * or dentry operations (a single path component relative to an ino). The
27 * exception to this is open_root_dentry(), which will open the mount
28 * point by name.
29 */
30
31 const struct dentry_operations ceph_dentry_ops;
32
33 static bool __dentry_lease_is_valid(struct ceph_dentry_info *di);
34 static int __dir_lease_try_check(const struct dentry *dentry);
35
36 /*
37 * Initialize ceph dentry state.
38 */
ceph_d_init(struct dentry * dentry)39 static int ceph_d_init(struct dentry *dentry)
40 {
41 struct ceph_dentry_info *di;
42 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);
43
44 di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
45 if (!di)
46 return -ENOMEM; /* oh well */
47
48 di->dentry = dentry;
49 di->lease_session = NULL;
50 di->time = jiffies;
51 dentry->d_fsdata = di;
52 INIT_LIST_HEAD(&di->lease_list);
53
54 atomic64_inc(&mdsc->metric.total_dentries);
55
56 return 0;
57 }
58
59 /*
60 * for f_pos for readdir:
61 * - hash order:
62 * (0xff << 52) | ((24 bits hash) << 28) |
63 * (the nth entry has hash collision);
64 * - frag+name order;
65 * ((frag value) << 28) | (the nth entry in frag);
66 */
67 #define OFFSET_BITS 28
68 #define OFFSET_MASK ((1 << OFFSET_BITS) - 1)
69 #define HASH_ORDER (0xffull << (OFFSET_BITS + 24))
ceph_make_fpos(unsigned high,unsigned off,bool hash_order)70 loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
71 {
72 loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
73 if (hash_order)
74 fpos |= HASH_ORDER;
75 return fpos;
76 }
77
is_hash_order(loff_t p)78 static bool is_hash_order(loff_t p)
79 {
80 return (p & HASH_ORDER) == HASH_ORDER;
81 }
82
fpos_frag(loff_t p)83 static unsigned fpos_frag(loff_t p)
84 {
85 return p >> OFFSET_BITS;
86 }
87
fpos_hash(loff_t p)88 static unsigned fpos_hash(loff_t p)
89 {
90 return ceph_frag_value(fpos_frag(p));
91 }
92
fpos_off(loff_t p)93 static unsigned fpos_off(loff_t p)
94 {
95 return p & OFFSET_MASK;
96 }
97
fpos_cmp(loff_t l,loff_t r)98 static int fpos_cmp(loff_t l, loff_t r)
99 {
100 int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
101 if (v)
102 return v;
103 return (int)(fpos_off(l) - fpos_off(r));
104 }
105
106 /*
107 * make note of the last dentry we read, so we can
108 * continue at the same lexicographical point,
109 * regardless of what dir changes take place on the
110 * server.
111 */
note_last_dentry(struct ceph_fs_client * fsc,struct ceph_dir_file_info * dfi,const char * name,int len,unsigned next_offset)112 static int note_last_dentry(struct ceph_fs_client *fsc,
113 struct ceph_dir_file_info *dfi,
114 const char *name,
115 int len, unsigned next_offset)
116 {
117 char *buf = kmalloc(len+1, GFP_KERNEL);
118 if (!buf)
119 return -ENOMEM;
120 kfree(dfi->last_name);
121 dfi->last_name = buf;
122 memcpy(dfi->last_name, name, len);
123 dfi->last_name[len] = 0;
124 dfi->next_offset = next_offset;
125 doutc(fsc->client, "'%s'\n", dfi->last_name);
126 return 0;
127 }
128
129
130 static struct dentry *
__dcache_find_get_entry(struct dentry * parent,u64 idx,struct ceph_readdir_cache_control * cache_ctl)131 __dcache_find_get_entry(struct dentry *parent, u64 idx,
132 struct ceph_readdir_cache_control *cache_ctl)
133 {
134 struct inode *dir = d_inode(parent);
135 struct ceph_client *cl = ceph_inode_to_client(dir);
136 struct dentry *dentry;
137 unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
138 loff_t ptr_pos = idx * sizeof(struct dentry *);
139 pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
140
141 if (ptr_pos >= i_size_read(dir))
142 return NULL;
143
144 if (!cache_ctl->page || ptr_pgoff != cache_ctl->page->index) {
145 ceph_readdir_cache_release(cache_ctl);
146 cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
147 if (!cache_ctl->page) {
148 doutc(cl, " page %lu not found\n", ptr_pgoff);
149 return ERR_PTR(-EAGAIN);
150 }
151 /* reading/filling the cache are serialized by
152 i_rwsem, no need to use page lock */
153 unlock_page(cache_ctl->page);
154 cache_ctl->dentries = kmap(cache_ctl->page);
155 }
156
157 cache_ctl->index = idx & idx_mask;
158
159 rcu_read_lock();
160 spin_lock(&parent->d_lock);
161 /* check i_size again here, because empty directory can be
162 * marked as complete while not holding the i_rwsem. */
163 if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))
164 dentry = cache_ctl->dentries[cache_ctl->index];
165 else
166 dentry = NULL;
167 spin_unlock(&parent->d_lock);
168 if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
169 dentry = NULL;
170 rcu_read_unlock();
171 return dentry ? : ERR_PTR(-EAGAIN);
172 }
173
174 /*
175 * When possible, we try to satisfy a readdir by peeking at the
176 * dcache. We make this work by carefully ordering dentries on
177 * d_children when we initially get results back from the MDS, and
178 * falling back to a "normal" sync readdir if any dentries in the dir
179 * are dropped.
180 *
181 * Complete dir indicates that we have all dentries in the dir. It is
182 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
183 * the MDS if/when the directory is modified).
184 */
__dcache_readdir(struct file * file,struct dir_context * ctx,int shared_gen)185 static int __dcache_readdir(struct file *file, struct dir_context *ctx,
186 int shared_gen)
187 {
188 struct ceph_dir_file_info *dfi = file->private_data;
189 struct dentry *parent = file->f_path.dentry;
190 struct inode *dir = d_inode(parent);
191 struct ceph_fs_client *fsc = ceph_inode_to_fs_client(dir);
192 struct ceph_client *cl = ceph_inode_to_client(dir);
193 struct dentry *dentry, *last = NULL;
194 struct ceph_dentry_info *di;
195 struct ceph_readdir_cache_control cache_ctl = {};
196 u64 idx = 0;
197 int err = 0;
198
199 doutc(cl, "%p %llx.%llx v%u at %llx\n", dir, ceph_vinop(dir),
200 (unsigned)shared_gen, ctx->pos);
201
202 /* search start position */
203 if (ctx->pos > 2) {
204 u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
205 while (count > 0) {
206 u64 step = count >> 1;
207 dentry = __dcache_find_get_entry(parent, idx + step,
208 &cache_ctl);
209 if (!dentry) {
210 /* use linar search */
211 idx = 0;
212 break;
213 }
214 if (IS_ERR(dentry)) {
215 err = PTR_ERR(dentry);
216 goto out;
217 }
218 di = ceph_dentry(dentry);
219 spin_lock(&dentry->d_lock);
220 if (fpos_cmp(di->offset, ctx->pos) < 0) {
221 idx += step + 1;
222 count -= step + 1;
223 } else {
224 count = step;
225 }
226 spin_unlock(&dentry->d_lock);
227 dput(dentry);
228 }
229
230 doutc(cl, "%p %llx.%llx cache idx %llu\n", dir,
231 ceph_vinop(dir), idx);
232 }
233
234
235 for (;;) {
236 bool emit_dentry = false;
237 dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
238 if (!dentry) {
239 dfi->file_info.flags |= CEPH_F_ATEND;
240 err = 0;
241 break;
242 }
243 if (IS_ERR(dentry)) {
244 err = PTR_ERR(dentry);
245 goto out;
246 }
247
248 spin_lock(&dentry->d_lock);
249 di = ceph_dentry(dentry);
250 if (d_unhashed(dentry) ||
251 d_really_is_negative(dentry) ||
252 di->lease_shared_gen != shared_gen ||
253 ((dentry->d_flags & DCACHE_NOKEY_NAME) &&
254 fscrypt_has_encryption_key(dir))) {
255 spin_unlock(&dentry->d_lock);
256 dput(dentry);
257 err = -EAGAIN;
258 goto out;
259 }
260 if (fpos_cmp(ctx->pos, di->offset) <= 0) {
261 __ceph_dentry_dir_lease_touch(di);
262 emit_dentry = true;
263 }
264 spin_unlock(&dentry->d_lock);
265
266 if (emit_dentry) {
267 doutc(cl, " %llx dentry %p %pd %p\n", di->offset,
268 dentry, dentry, d_inode(dentry));
269 ctx->pos = di->offset;
270 if (!dir_emit(ctx, dentry->d_name.name,
271 dentry->d_name.len, ceph_present_inode(d_inode(dentry)),
272 d_inode(dentry)->i_mode >> 12)) {
273 dput(dentry);
274 err = 0;
275 break;
276 }
277 ctx->pos++;
278
279 if (last)
280 dput(last);
281 last = dentry;
282 } else {
283 dput(dentry);
284 }
285 }
286 out:
287 ceph_readdir_cache_release(&cache_ctl);
288 if (last) {
289 int ret;
290 di = ceph_dentry(last);
291 ret = note_last_dentry(fsc, dfi, last->d_name.name,
292 last->d_name.len,
293 fpos_off(di->offset) + 1);
294 if (ret < 0)
295 err = ret;
296 dput(last);
297 /* last_name no longer match cache index */
298 if (dfi->readdir_cache_idx >= 0) {
299 dfi->readdir_cache_idx = -1;
300 dfi->dir_release_count = 0;
301 }
302 }
303 return err;
304 }
305
need_send_readdir(struct ceph_dir_file_info * dfi,loff_t pos)306 static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)
307 {
308 if (!dfi->last_readdir)
309 return true;
310 if (is_hash_order(pos))
311 return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));
312 else
313 return dfi->frag != fpos_frag(pos);
314 }
315
ceph_readdir(struct file * file,struct dir_context * ctx)316 static int ceph_readdir(struct file *file, struct dir_context *ctx)
317 {
318 struct ceph_dir_file_info *dfi = file->private_data;
319 struct inode *inode = file_inode(file);
320 struct ceph_inode_info *ci = ceph_inode(inode);
321 struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
322 struct ceph_mds_client *mdsc = fsc->mdsc;
323 struct ceph_client *cl = fsc->client;
324 int i;
325 int err;
326 unsigned frag = -1;
327 struct ceph_mds_reply_info_parsed *rinfo;
328
329 doutc(cl, "%p %llx.%llx file %p pos %llx\n", inode,
330 ceph_vinop(inode), file, ctx->pos);
331 if (dfi->file_info.flags & CEPH_F_ATEND)
332 return 0;
333
334 /* always start with . and .. */
335 if (ctx->pos == 0) {
336 doutc(cl, "%p %llx.%llx off 0 -> '.'\n", inode,
337 ceph_vinop(inode));
338 if (!dir_emit(ctx, ".", 1, ceph_present_inode(inode),
339 inode->i_mode >> 12))
340 return 0;
341 ctx->pos = 1;
342 }
343 if (ctx->pos == 1) {
344 u64 ino;
345 struct dentry *dentry = file->f_path.dentry;
346
347 spin_lock(&dentry->d_lock);
348 ino = ceph_present_inode(dentry->d_parent->d_inode);
349 spin_unlock(&dentry->d_lock);
350
351 doutc(cl, "%p %llx.%llx off 1 -> '..'\n", inode,
352 ceph_vinop(inode));
353 if (!dir_emit(ctx, "..", 2, ino, inode->i_mode >> 12))
354 return 0;
355 ctx->pos = 2;
356 }
357
358 err = ceph_fscrypt_prepare_readdir(inode);
359 if (err < 0)
360 return err;
361
362 spin_lock(&ci->i_ceph_lock);
363 /* request Fx cap. if have Fx, we don't need to release Fs cap
364 * for later create/unlink. */
365 __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_WR);
366 /* can we use the dcache? */
367 if (ceph_test_mount_opt(fsc, DCACHE) &&
368 !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
369 ceph_snap(inode) != CEPH_SNAPDIR &&
370 __ceph_dir_is_complete_ordered(ci) &&
371 __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
372 int shared_gen = atomic_read(&ci->i_shared_gen);
373
374 spin_unlock(&ci->i_ceph_lock);
375 err = __dcache_readdir(file, ctx, shared_gen);
376 if (err != -EAGAIN)
377 return err;
378 } else {
379 spin_unlock(&ci->i_ceph_lock);
380 }
381
382 /* proceed with a normal readdir */
383 more:
384 /* do we have the correct frag content buffered? */
385 if (need_send_readdir(dfi, ctx->pos)) {
386 struct ceph_mds_request *req;
387 int op = ceph_snap(inode) == CEPH_SNAPDIR ?
388 CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
389
390 /* discard old result, if any */
391 if (dfi->last_readdir) {
392 ceph_mdsc_put_request(dfi->last_readdir);
393 dfi->last_readdir = NULL;
394 }
395
396 if (is_hash_order(ctx->pos)) {
397 /* fragtree isn't always accurate. choose frag
398 * based on previous reply when possible. */
399 if (frag == (unsigned)-1)
400 frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
401 NULL, NULL);
402 } else {
403 frag = fpos_frag(ctx->pos);
404 }
405
406 doutc(cl, "fetching %p %llx.%llx frag %x offset '%s'\n",
407 inode, ceph_vinop(inode), frag, dfi->last_name);
408 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
409 if (IS_ERR(req))
410 return PTR_ERR(req);
411
412 err = ceph_alloc_readdir_reply_buffer(req, inode);
413 if (err) {
414 ceph_mdsc_put_request(req);
415 return err;
416 }
417 /* hints to request -> mds selection code */
418 req->r_direct_mode = USE_AUTH_MDS;
419 if (op == CEPH_MDS_OP_READDIR) {
420 req->r_direct_hash = ceph_frag_value(frag);
421 __set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
422 req->r_inode_drop = CEPH_CAP_FILE_EXCL;
423 }
424 if (dfi->last_name) {
425 struct qstr d_name = { .name = dfi->last_name,
426 .len = strlen(dfi->last_name) };
427
428 req->r_path2 = kzalloc(NAME_MAX + 1, GFP_KERNEL);
429 if (!req->r_path2) {
430 ceph_mdsc_put_request(req);
431 return -ENOMEM;
432 }
433
434 err = ceph_encode_encrypted_dname(inode, &d_name,
435 req->r_path2);
436 if (err < 0) {
437 ceph_mdsc_put_request(req);
438 return err;
439 }
440 } else if (is_hash_order(ctx->pos)) {
441 req->r_args.readdir.offset_hash =
442 cpu_to_le32(fpos_hash(ctx->pos));
443 }
444
445 req->r_dir_release_cnt = dfi->dir_release_count;
446 req->r_dir_ordered_cnt = dfi->dir_ordered_count;
447 req->r_readdir_cache_idx = dfi->readdir_cache_idx;
448 req->r_readdir_offset = dfi->next_offset;
449 req->r_args.readdir.frag = cpu_to_le32(frag);
450 req->r_args.readdir.flags =
451 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
452
453 req->r_inode = inode;
454 ihold(inode);
455 req->r_dentry = dget(file->f_path.dentry);
456 err = ceph_mdsc_do_request(mdsc, NULL, req);
457 if (err < 0) {
458 ceph_mdsc_put_request(req);
459 return err;
460 }
461 doutc(cl, "%p %llx.%llx got and parsed readdir result=%d"
462 "on frag %x, end=%d, complete=%d, hash_order=%d\n",
463 inode, ceph_vinop(inode), err, frag,
464 (int)req->r_reply_info.dir_end,
465 (int)req->r_reply_info.dir_complete,
466 (int)req->r_reply_info.hash_order);
467
468 rinfo = &req->r_reply_info;
469 if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
470 frag = le32_to_cpu(rinfo->dir_dir->frag);
471 if (!rinfo->hash_order) {
472 dfi->next_offset = req->r_readdir_offset;
473 /* adjust ctx->pos to beginning of frag */
474 ctx->pos = ceph_make_fpos(frag,
475 dfi->next_offset,
476 false);
477 }
478 }
479
480 dfi->frag = frag;
481 dfi->last_readdir = req;
482
483 if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
484 dfi->readdir_cache_idx = req->r_readdir_cache_idx;
485 if (dfi->readdir_cache_idx < 0) {
486 /* preclude from marking dir ordered */
487 dfi->dir_ordered_count = 0;
488 } else if (ceph_frag_is_leftmost(frag) &&
489 dfi->next_offset == 2) {
490 /* note dir version at start of readdir so
491 * we can tell if any dentries get dropped */
492 dfi->dir_release_count = req->r_dir_release_cnt;
493 dfi->dir_ordered_count = req->r_dir_ordered_cnt;
494 }
495 } else {
496 doutc(cl, "%p %llx.%llx !did_prepopulate\n", inode,
497 ceph_vinop(inode));
498 /* disable readdir cache */
499 dfi->readdir_cache_idx = -1;
500 /* preclude from marking dir complete */
501 dfi->dir_release_count = 0;
502 }
503
504 /* note next offset and last dentry name */
505 if (rinfo->dir_nr > 0) {
506 struct ceph_mds_reply_dir_entry *rde =
507 rinfo->dir_entries + (rinfo->dir_nr-1);
508 unsigned next_offset = req->r_reply_info.dir_end ?
509 2 : (fpos_off(rde->offset) + 1);
510 err = note_last_dentry(fsc, dfi, rde->name,
511 rde->name_len, next_offset);
512 if (err) {
513 ceph_mdsc_put_request(dfi->last_readdir);
514 dfi->last_readdir = NULL;
515 return err;
516 }
517 } else if (req->r_reply_info.dir_end) {
518 dfi->next_offset = 2;
519 /* keep last name */
520 }
521 }
522
523 rinfo = &dfi->last_readdir->r_reply_info;
524 doutc(cl, "%p %llx.%llx frag %x num %d pos %llx chunk first %llx\n",
525 inode, ceph_vinop(inode), dfi->frag, rinfo->dir_nr, ctx->pos,
526 rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
527
528 i = 0;
529 /* search start position */
530 if (rinfo->dir_nr > 0) {
531 int step, nr = rinfo->dir_nr;
532 while (nr > 0) {
533 step = nr >> 1;
534 if (rinfo->dir_entries[i + step].offset < ctx->pos) {
535 i += step + 1;
536 nr -= step + 1;
537 } else {
538 nr = step;
539 }
540 }
541 }
542 for (; i < rinfo->dir_nr; i++) {
543 struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
544
545 if (rde->offset < ctx->pos) {
546 pr_warn_client(cl,
547 "%p %llx.%llx rde->offset 0x%llx ctx->pos 0x%llx\n",
548 inode, ceph_vinop(inode), rde->offset, ctx->pos);
549 return -EIO;
550 }
551
552 if (WARN_ON_ONCE(!rde->inode.in))
553 return -EIO;
554
555 ctx->pos = rde->offset;
556 doutc(cl, "%p %llx.%llx (%d/%d) -> %llx '%.*s' %p\n", inode,
557 ceph_vinop(inode), i, rinfo->dir_nr, ctx->pos,
558 rde->name_len, rde->name, &rde->inode.in);
559
560 if (!dir_emit(ctx, rde->name, rde->name_len,
561 ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
562 le32_to_cpu(rde->inode.in->mode) >> 12)) {
563 /*
564 * NOTE: Here no need to put the 'dfi->last_readdir',
565 * because when dir_emit stops us it's most likely
566 * doesn't have enough memory, etc. So for next readdir
567 * it will continue.
568 */
569 doutc(cl, "filldir stopping us...\n");
570 return 0;
571 }
572
573 /* Reset the lengths to their original allocated vals */
574 ctx->pos++;
575 }
576
577 ceph_mdsc_put_request(dfi->last_readdir);
578 dfi->last_readdir = NULL;
579
580 if (dfi->next_offset > 2) {
581 frag = dfi->frag;
582 goto more;
583 }
584
585 /* more frags? */
586 if (!ceph_frag_is_rightmost(dfi->frag)) {
587 frag = ceph_frag_next(dfi->frag);
588 if (is_hash_order(ctx->pos)) {
589 loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
590 dfi->next_offset, true);
591 if (new_pos > ctx->pos)
592 ctx->pos = new_pos;
593 /* keep last_name */
594 } else {
595 ctx->pos = ceph_make_fpos(frag, dfi->next_offset,
596 false);
597 kfree(dfi->last_name);
598 dfi->last_name = NULL;
599 }
600 doutc(cl, "%p %llx.%llx next frag is %x\n", inode,
601 ceph_vinop(inode), frag);
602 goto more;
603 }
604 dfi->file_info.flags |= CEPH_F_ATEND;
605
606 /*
607 * if dir_release_count still matches the dir, no dentries
608 * were released during the whole readdir, and we should have
609 * the complete dir contents in our cache.
610 */
611 if (atomic64_read(&ci->i_release_count) ==
612 dfi->dir_release_count) {
613 spin_lock(&ci->i_ceph_lock);
614 if (dfi->dir_ordered_count ==
615 atomic64_read(&ci->i_ordered_count)) {
616 doutc(cl, " marking %p %llx.%llx complete and ordered\n",
617 inode, ceph_vinop(inode));
618 /* use i_size to track number of entries in
619 * readdir cache */
620 BUG_ON(dfi->readdir_cache_idx < 0);
621 i_size_write(inode, dfi->readdir_cache_idx *
622 sizeof(struct dentry*));
623 } else {
624 doutc(cl, " marking %llx.%llx complete\n",
625 ceph_vinop(inode));
626 }
627 __ceph_dir_set_complete(ci, dfi->dir_release_count,
628 dfi->dir_ordered_count);
629 spin_unlock(&ci->i_ceph_lock);
630 }
631 doutc(cl, "%p %llx.%llx file %p done.\n", inode, ceph_vinop(inode),
632 file);
633 return 0;
634 }
635
reset_readdir(struct ceph_dir_file_info * dfi)636 static void reset_readdir(struct ceph_dir_file_info *dfi)
637 {
638 if (dfi->last_readdir) {
639 ceph_mdsc_put_request(dfi->last_readdir);
640 dfi->last_readdir = NULL;
641 }
642 kfree(dfi->last_name);
643 dfi->last_name = NULL;
644 dfi->dir_release_count = 0;
645 dfi->readdir_cache_idx = -1;
646 dfi->next_offset = 2; /* compensate for . and .. */
647 dfi->file_info.flags &= ~CEPH_F_ATEND;
648 }
649
650 /*
651 * discard buffered readdir content on seekdir(0), or seek to new frag,
652 * or seek prior to current chunk
653 */
need_reset_readdir(struct ceph_dir_file_info * dfi,loff_t new_pos)654 static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)
655 {
656 struct ceph_mds_reply_info_parsed *rinfo;
657 loff_t chunk_offset;
658 if (new_pos == 0)
659 return true;
660 if (is_hash_order(new_pos)) {
661 /* no need to reset last_name for a forward seek when
662 * dentries are sotred in hash order */
663 } else if (dfi->frag != fpos_frag(new_pos)) {
664 return true;
665 }
666 rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;
667 if (!rinfo || !rinfo->dir_nr)
668 return true;
669 chunk_offset = rinfo->dir_entries[0].offset;
670 return new_pos < chunk_offset ||
671 is_hash_order(new_pos) != is_hash_order(chunk_offset);
672 }
673
ceph_dir_llseek(struct file * file,loff_t offset,int whence)674 static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
675 {
676 struct ceph_dir_file_info *dfi = file->private_data;
677 struct inode *inode = file->f_mapping->host;
678 struct ceph_client *cl = ceph_inode_to_client(inode);
679 loff_t retval;
680
681 inode_lock(inode);
682 retval = -EINVAL;
683 switch (whence) {
684 case SEEK_CUR:
685 offset += file->f_pos;
686 break;
687 case SEEK_SET:
688 break;
689 case SEEK_END:
690 retval = -EOPNOTSUPP;
691 goto out;
692 default:
693 goto out;
694 }
695
696 if (offset >= 0) {
697 if (need_reset_readdir(dfi, offset)) {
698 doutc(cl, "%p %llx.%llx dropping %p content\n",
699 inode, ceph_vinop(inode), file);
700 reset_readdir(dfi);
701 } else if (is_hash_order(offset) && offset > file->f_pos) {
702 /* for hash offset, we don't know if a forward seek
703 * is within same frag */
704 dfi->dir_release_count = 0;
705 dfi->readdir_cache_idx = -1;
706 }
707
708 if (offset != file->f_pos) {
709 file->f_pos = offset;
710 dfi->file_info.flags &= ~CEPH_F_ATEND;
711 }
712 retval = offset;
713 }
714 out:
715 inode_unlock(inode);
716 return retval;
717 }
718
719 /*
720 * Handle lookups for the hidden .snap directory.
721 */
ceph_handle_snapdir(struct ceph_mds_request * req,struct dentry * dentry)722 struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
723 struct dentry *dentry)
724 {
725 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);
726 struct inode *parent = d_inode(dentry->d_parent); /* we hold i_rwsem */
727 struct ceph_client *cl = ceph_inode_to_client(parent);
728
729 /* .snap dir? */
730 if (ceph_snap(parent) == CEPH_NOSNAP &&
731 strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {
732 struct dentry *res;
733 struct inode *inode = ceph_get_snapdir(parent);
734
735 res = d_splice_alias(inode, dentry);
736 doutc(cl, "ENOENT on snapdir %p '%pd', linking to "
737 "snapdir %p %llx.%llx. Spliced dentry %p\n",
738 dentry, dentry, inode, ceph_vinop(inode), res);
739 if (res)
740 dentry = res;
741 }
742 return dentry;
743 }
744
745 /*
746 * Figure out final result of a lookup/open request.
747 *
748 * Mainly, make sure we return the final req->r_dentry (if it already
749 * existed) in place of the original VFS-provided dentry when they
750 * differ.
751 *
752 * Gracefully handle the case where the MDS replies with -ENOENT and
753 * no trace (which it may do, at its discretion, e.g., if it doesn't
754 * care to issue a lease on the negative dentry).
755 */
ceph_finish_lookup(struct ceph_mds_request * req,struct dentry * dentry,int err)756 struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
757 struct dentry *dentry, int err)
758 {
759 struct ceph_client *cl = req->r_mdsc->fsc->client;
760
761 if (err == -ENOENT) {
762 /* no trace? */
763 err = 0;
764 if (!req->r_reply_info.head->is_dentry) {
765 doutc(cl,
766 "ENOENT and no trace, dentry %p inode %llx.%llx\n",
767 dentry, ceph_vinop(d_inode(dentry)));
768 if (d_really_is_positive(dentry)) {
769 d_drop(dentry);
770 err = -ENOENT;
771 } else {
772 d_add(dentry, NULL);
773 }
774 }
775 }
776 if (err)
777 dentry = ERR_PTR(err);
778 else if (dentry != req->r_dentry)
779 dentry = dget(req->r_dentry); /* we got spliced */
780 else
781 dentry = NULL;
782 return dentry;
783 }
784
is_root_ceph_dentry(struct inode * inode,struct dentry * dentry)785 static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
786 {
787 return ceph_ino(inode) == CEPH_INO_ROOT &&
788 strncmp(dentry->d_name.name, ".ceph", 5) == 0;
789 }
790
791 /*
792 * Look up a single dir entry. If there is a lookup intent, inform
793 * the MDS so that it gets our 'caps wanted' value in a single op.
794 */
ceph_lookup(struct inode * dir,struct dentry * dentry,unsigned int flags)795 static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
796 unsigned int flags)
797 {
798 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dir->i_sb);
799 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
800 struct ceph_client *cl = fsc->client;
801 struct ceph_mds_request *req;
802 int op;
803 int mask;
804 int err;
805
806 doutc(cl, "%p %llx.%llx/'%pd' dentry %p\n", dir, ceph_vinop(dir),
807 dentry, dentry);
808
809 if (dentry->d_name.len > NAME_MAX)
810 return ERR_PTR(-ENAMETOOLONG);
811
812 if (IS_ENCRYPTED(dir)) {
813 bool had_key = fscrypt_has_encryption_key(dir);
814
815 err = fscrypt_prepare_lookup_partial(dir, dentry);
816 if (err < 0)
817 return ERR_PTR(err);
818
819 /* mark directory as incomplete if it has been unlocked */
820 if (!had_key && fscrypt_has_encryption_key(dir))
821 ceph_dir_clear_complete(dir);
822 }
823
824 /* can we conclude ENOENT locally? */
825 if (d_really_is_negative(dentry)) {
826 struct ceph_inode_info *ci = ceph_inode(dir);
827 struct ceph_dentry_info *di = ceph_dentry(dentry);
828
829 spin_lock(&ci->i_ceph_lock);
830 doutc(cl, " dir %llx.%llx flags are 0x%lx\n",
831 ceph_vinop(dir), ci->i_ceph_flags);
832 if (strncmp(dentry->d_name.name,
833 fsc->mount_options->snapdir_name,
834 dentry->d_name.len) &&
835 !is_root_ceph_dentry(dir, dentry) &&
836 ceph_test_mount_opt(fsc, DCACHE) &&
837 __ceph_dir_is_complete(ci) &&
838 __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
839 __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
840 spin_unlock(&ci->i_ceph_lock);
841 doutc(cl, " dir %llx.%llx complete, -ENOENT\n",
842 ceph_vinop(dir));
843 d_add(dentry, NULL);
844 di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
845 return NULL;
846 }
847 spin_unlock(&ci->i_ceph_lock);
848 }
849
850 op = ceph_snap(dir) == CEPH_SNAPDIR ?
851 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
852 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
853 if (IS_ERR(req))
854 return ERR_CAST(req);
855 req->r_dentry = dget(dentry);
856 req->r_num_caps = 2;
857
858 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
859 if (ceph_security_xattr_wanted(dir))
860 mask |= CEPH_CAP_XATTR_SHARED;
861 req->r_args.getattr.mask = cpu_to_le32(mask);
862
863 ihold(dir);
864 req->r_parent = dir;
865 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
866 err = ceph_mdsc_do_request(mdsc, NULL, req);
867 if (err == -ENOENT) {
868 struct dentry *res;
869
870 res = ceph_handle_snapdir(req, dentry);
871 if (IS_ERR(res)) {
872 err = PTR_ERR(res);
873 } else {
874 dentry = res;
875 err = 0;
876 }
877 }
878 dentry = ceph_finish_lookup(req, dentry, err);
879 ceph_mdsc_put_request(req); /* will dput(dentry) */
880 doutc(cl, "result=%p\n", dentry);
881 return dentry;
882 }
883
884 /*
885 * If we do a create but get no trace back from the MDS, follow up with
886 * a lookup (the VFS expects us to link up the provided dentry).
887 */
ceph_handle_notrace_create(struct inode * dir,struct dentry * dentry)888 int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
889 {
890 struct dentry *result = ceph_lookup(dir, dentry, 0);
891
892 if (result && !IS_ERR(result)) {
893 /*
894 * We created the item, then did a lookup, and found
895 * it was already linked to another inode we already
896 * had in our cache (and thus got spliced). To not
897 * confuse VFS (especially when inode is a directory),
898 * we don't link our dentry to that inode, return an
899 * error instead.
900 *
901 * This event should be rare and it happens only when
902 * we talk to old MDS. Recent MDS does not send traceless
903 * reply for request that creates new inode.
904 */
905 d_drop(result);
906 return -ESTALE;
907 }
908 return PTR_ERR(result);
909 }
910
ceph_mknod(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev)911 static int ceph_mknod(struct mnt_idmap *idmap, struct inode *dir,
912 struct dentry *dentry, umode_t mode, dev_t rdev)
913 {
914 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
915 struct ceph_client *cl = mdsc->fsc->client;
916 struct ceph_mds_request *req;
917 struct ceph_acl_sec_ctx as_ctx = {};
918 int err;
919
920 if (ceph_snap(dir) != CEPH_NOSNAP)
921 return -EROFS;
922
923 err = ceph_wait_on_conflict_unlink(dentry);
924 if (err)
925 return err;
926
927 if (ceph_quota_is_max_files_exceeded(dir)) {
928 err = -EDQUOT;
929 goto out;
930 }
931
932 doutc(cl, "%p %llx.%llx/'%pd' dentry %p mode 0%ho rdev %d\n",
933 dir, ceph_vinop(dir), dentry, dentry, mode, rdev);
934 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
935 if (IS_ERR(req)) {
936 err = PTR_ERR(req);
937 goto out;
938 }
939
940 req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);
941 if (IS_ERR(req->r_new_inode)) {
942 err = PTR_ERR(req->r_new_inode);
943 req->r_new_inode = NULL;
944 goto out_req;
945 }
946
947 if (S_ISREG(mode) && IS_ENCRYPTED(dir))
948 set_bit(CEPH_MDS_R_FSCRYPT_FILE, &req->r_req_flags);
949
950 req->r_dentry = dget(dentry);
951 req->r_num_caps = 2;
952 req->r_parent = dir;
953 ihold(dir);
954 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
955 req->r_mnt_idmap = mnt_idmap_get(idmap);
956 req->r_args.mknod.mode = cpu_to_le32(mode);
957 req->r_args.mknod.rdev = cpu_to_le32(rdev);
958 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
959 CEPH_CAP_XATTR_EXCL;
960 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
961
962 ceph_as_ctx_to_req(req, &as_ctx);
963
964 err = ceph_mdsc_do_request(mdsc, dir, req);
965 if (!err && !req->r_reply_info.head->is_dentry)
966 err = ceph_handle_notrace_create(dir, dentry);
967 out_req:
968 ceph_mdsc_put_request(req);
969 out:
970 if (!err)
971 ceph_init_inode_acls(d_inode(dentry), &as_ctx);
972 else
973 d_drop(dentry);
974 ceph_release_acl_sec_ctx(&as_ctx);
975 return err;
976 }
977
ceph_create(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,bool excl)978 static int ceph_create(struct mnt_idmap *idmap, struct inode *dir,
979 struct dentry *dentry, umode_t mode, bool excl)
980 {
981 return ceph_mknod(idmap, dir, dentry, mode, 0);
982 }
983
984 #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
prep_encrypted_symlink_target(struct ceph_mds_request * req,const char * dest)985 static int prep_encrypted_symlink_target(struct ceph_mds_request *req,
986 const char *dest)
987 {
988 int err;
989 int len = strlen(dest);
990 struct fscrypt_str osd_link = FSTR_INIT(NULL, 0);
991
992 err = fscrypt_prepare_symlink(req->r_parent, dest, len, PATH_MAX,
993 &osd_link);
994 if (err)
995 goto out;
996
997 err = fscrypt_encrypt_symlink(req->r_new_inode, dest, len, &osd_link);
998 if (err)
999 goto out;
1000
1001 req->r_path2 = kmalloc(CEPH_BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL);
1002 if (!req->r_path2) {
1003 err = -ENOMEM;
1004 goto out;
1005 }
1006
1007 len = ceph_base64_encode(osd_link.name, osd_link.len, req->r_path2);
1008 req->r_path2[len] = '\0';
1009 out:
1010 fscrypt_fname_free_buffer(&osd_link);
1011 return err;
1012 }
1013 #else
prep_encrypted_symlink_target(struct ceph_mds_request * req,const char * dest)1014 static int prep_encrypted_symlink_target(struct ceph_mds_request *req,
1015 const char *dest)
1016 {
1017 return -EOPNOTSUPP;
1018 }
1019 #endif
1020
ceph_symlink(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,const char * dest)1021 static int ceph_symlink(struct mnt_idmap *idmap, struct inode *dir,
1022 struct dentry *dentry, const char *dest)
1023 {
1024 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
1025 struct ceph_client *cl = mdsc->fsc->client;
1026 struct ceph_mds_request *req;
1027 struct ceph_acl_sec_ctx as_ctx = {};
1028 umode_t mode = S_IFLNK | 0777;
1029 int err;
1030
1031 if (ceph_snap(dir) != CEPH_NOSNAP)
1032 return -EROFS;
1033
1034 err = ceph_wait_on_conflict_unlink(dentry);
1035 if (err)
1036 return err;
1037
1038 if (ceph_quota_is_max_files_exceeded(dir)) {
1039 err = -EDQUOT;
1040 goto out;
1041 }
1042
1043 doutc(cl, "%p %llx.%llx/'%pd' to '%s'\n", dir, ceph_vinop(dir), dentry,
1044 dest);
1045 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
1046 if (IS_ERR(req)) {
1047 err = PTR_ERR(req);
1048 goto out;
1049 }
1050
1051 req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);
1052 if (IS_ERR(req->r_new_inode)) {
1053 err = PTR_ERR(req->r_new_inode);
1054 req->r_new_inode = NULL;
1055 goto out_req;
1056 }
1057
1058 req->r_parent = dir;
1059 ihold(dir);
1060
1061 if (IS_ENCRYPTED(req->r_new_inode)) {
1062 err = prep_encrypted_symlink_target(req, dest);
1063 if (err)
1064 goto out_req;
1065 } else {
1066 req->r_path2 = kstrdup(dest, GFP_KERNEL);
1067 if (!req->r_path2) {
1068 err = -ENOMEM;
1069 goto out_req;
1070 }
1071 }
1072
1073 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1074 req->r_mnt_idmap = mnt_idmap_get(idmap);
1075 req->r_dentry = dget(dentry);
1076 req->r_num_caps = 2;
1077 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
1078 CEPH_CAP_XATTR_EXCL;
1079 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1080
1081 ceph_as_ctx_to_req(req, &as_ctx);
1082
1083 err = ceph_mdsc_do_request(mdsc, dir, req);
1084 if (!err && !req->r_reply_info.head->is_dentry)
1085 err = ceph_handle_notrace_create(dir, dentry);
1086 out_req:
1087 ceph_mdsc_put_request(req);
1088 out:
1089 if (err)
1090 d_drop(dentry);
1091 ceph_release_acl_sec_ctx(&as_ctx);
1092 return err;
1093 }
1094
ceph_mkdir(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)1095 static int ceph_mkdir(struct mnt_idmap *idmap, struct inode *dir,
1096 struct dentry *dentry, umode_t mode)
1097 {
1098 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
1099 struct ceph_client *cl = mdsc->fsc->client;
1100 struct ceph_mds_request *req;
1101 struct ceph_acl_sec_ctx as_ctx = {};
1102 int err;
1103 int op;
1104
1105 err = ceph_wait_on_conflict_unlink(dentry);
1106 if (err)
1107 return err;
1108
1109 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1110 /* mkdir .snap/foo is a MKSNAP */
1111 op = CEPH_MDS_OP_MKSNAP;
1112 doutc(cl, "mksnap %llx.%llx/'%pd' dentry %p\n",
1113 ceph_vinop(dir), dentry, dentry);
1114 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1115 doutc(cl, "mkdir %llx.%llx/'%pd' dentry %p mode 0%ho\n",
1116 ceph_vinop(dir), dentry, dentry, mode);
1117 op = CEPH_MDS_OP_MKDIR;
1118 } else {
1119 err = -EROFS;
1120 goto out;
1121 }
1122
1123 if (op == CEPH_MDS_OP_MKDIR &&
1124 ceph_quota_is_max_files_exceeded(dir)) {
1125 err = -EDQUOT;
1126 goto out;
1127 }
1128 if ((op == CEPH_MDS_OP_MKSNAP) && IS_ENCRYPTED(dir) &&
1129 !fscrypt_has_encryption_key(dir)) {
1130 err = -ENOKEY;
1131 goto out;
1132 }
1133
1134
1135 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1136 if (IS_ERR(req)) {
1137 err = PTR_ERR(req);
1138 goto out;
1139 }
1140
1141 mode |= S_IFDIR;
1142 req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);
1143 if (IS_ERR(req->r_new_inode)) {
1144 err = PTR_ERR(req->r_new_inode);
1145 req->r_new_inode = NULL;
1146 goto out_req;
1147 }
1148
1149 req->r_dentry = dget(dentry);
1150 req->r_num_caps = 2;
1151 req->r_parent = dir;
1152 ihold(dir);
1153 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1154 if (op == CEPH_MDS_OP_MKDIR)
1155 req->r_mnt_idmap = mnt_idmap_get(idmap);
1156 req->r_args.mkdir.mode = cpu_to_le32(mode);
1157 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
1158 CEPH_CAP_XATTR_EXCL;
1159 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1160
1161 ceph_as_ctx_to_req(req, &as_ctx);
1162
1163 err = ceph_mdsc_do_request(mdsc, dir, req);
1164 if (!err &&
1165 !req->r_reply_info.head->is_target &&
1166 !req->r_reply_info.head->is_dentry)
1167 err = ceph_handle_notrace_create(dir, dentry);
1168 out_req:
1169 ceph_mdsc_put_request(req);
1170 out:
1171 if (!err)
1172 ceph_init_inode_acls(d_inode(dentry), &as_ctx);
1173 else
1174 d_drop(dentry);
1175 ceph_release_acl_sec_ctx(&as_ctx);
1176 return err;
1177 }
1178
ceph_link(struct dentry * old_dentry,struct inode * dir,struct dentry * dentry)1179 static int ceph_link(struct dentry *old_dentry, struct inode *dir,
1180 struct dentry *dentry)
1181 {
1182 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
1183 struct ceph_client *cl = mdsc->fsc->client;
1184 struct ceph_mds_request *req;
1185 int err;
1186
1187 if (dentry->d_flags & DCACHE_DISCONNECTED)
1188 return -EINVAL;
1189
1190 err = ceph_wait_on_conflict_unlink(dentry);
1191 if (err)
1192 return err;
1193
1194 if (ceph_snap(dir) != CEPH_NOSNAP)
1195 return -EROFS;
1196
1197 err = fscrypt_prepare_link(old_dentry, dir, dentry);
1198 if (err)
1199 return err;
1200
1201 doutc(cl, "%p %llx.%llx/'%pd' to '%pd'\n", dir, ceph_vinop(dir),
1202 old_dentry, dentry);
1203 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
1204 if (IS_ERR(req)) {
1205 d_drop(dentry);
1206 return PTR_ERR(req);
1207 }
1208 req->r_dentry = dget(dentry);
1209 req->r_num_caps = 2;
1210 req->r_old_dentry = dget(old_dentry);
1211 /*
1212 * The old_dentry maybe a DCACHE_DISCONNECTED dentry, then we
1213 * will just pass the ino# to MDSs.
1214 */
1215 if (old_dentry->d_flags & DCACHE_DISCONNECTED)
1216 req->r_ino2 = ceph_vino(d_inode(old_dentry));
1217 req->r_parent = dir;
1218 ihold(dir);
1219 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1220 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1221 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1222 /* release LINK_SHARED on source inode (mds will lock it) */
1223 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1224 err = ceph_mdsc_do_request(mdsc, dir, req);
1225 if (err) {
1226 d_drop(dentry);
1227 } else if (!req->r_reply_info.head->is_dentry) {
1228 ihold(d_inode(old_dentry));
1229 d_instantiate(dentry, d_inode(old_dentry));
1230 }
1231 ceph_mdsc_put_request(req);
1232 return err;
1233 }
1234
ceph_async_unlink_cb(struct ceph_mds_client * mdsc,struct ceph_mds_request * req)1235 static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,
1236 struct ceph_mds_request *req)
1237 {
1238 struct dentry *dentry = req->r_dentry;
1239 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);
1240 struct ceph_client *cl = fsc->client;
1241 struct ceph_dentry_info *di = ceph_dentry(dentry);
1242 int result = req->r_err ? req->r_err :
1243 le32_to_cpu(req->r_reply_info.head->result);
1244
1245 if (!test_bit(CEPH_DENTRY_ASYNC_UNLINK_BIT, &di->flags))
1246 pr_warn_client(cl,
1247 "dentry %p:%pd async unlink bit is not set\n",
1248 dentry, dentry);
1249
1250 spin_lock(&fsc->async_unlink_conflict_lock);
1251 hash_del_rcu(&di->hnode);
1252 spin_unlock(&fsc->async_unlink_conflict_lock);
1253
1254 spin_lock(&dentry->d_lock);
1255 di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1256 wake_up_bit(&di->flags, CEPH_DENTRY_ASYNC_UNLINK_BIT);
1257 spin_unlock(&dentry->d_lock);
1258
1259 synchronize_rcu();
1260
1261 if (result == -EJUKEBOX)
1262 goto out;
1263
1264 /* If op failed, mark everyone involved for errors */
1265 if (result) {
1266 int pathlen = 0;
1267 u64 base = 0;
1268 char *path = ceph_mdsc_build_path(mdsc, dentry, &pathlen,
1269 &base, 0);
1270
1271 /* mark error on parent + clear complete */
1272 mapping_set_error(req->r_parent->i_mapping, result);
1273 ceph_dir_clear_complete(req->r_parent);
1274
1275 /* drop the dentry -- we don't know its status */
1276 if (!d_unhashed(dentry))
1277 d_drop(dentry);
1278
1279 /* mark inode itself for an error (since metadata is bogus) */
1280 mapping_set_error(req->r_old_inode->i_mapping, result);
1281
1282 pr_warn_client(cl, "failure path=(%llx)%s result=%d!\n",
1283 base, IS_ERR(path) ? "<<bad>>" : path, result);
1284 ceph_mdsc_free_path(path, pathlen);
1285 }
1286 out:
1287 iput(req->r_old_inode);
1288 ceph_mdsc_release_dir_caps(req);
1289 }
1290
get_caps_for_async_unlink(struct inode * dir,struct dentry * dentry)1291 static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry)
1292 {
1293 struct ceph_inode_info *ci = ceph_inode(dir);
1294 struct ceph_dentry_info *di;
1295 int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK;
1296
1297 spin_lock(&ci->i_ceph_lock);
1298 if ((__ceph_caps_issued(ci, NULL) & want) == want) {
1299 ceph_take_cap_refs(ci, want, false);
1300 got = want;
1301 }
1302 spin_unlock(&ci->i_ceph_lock);
1303
1304 /* If we didn't get anything, return 0 */
1305 if (!got)
1306 return 0;
1307
1308 spin_lock(&dentry->d_lock);
1309 di = ceph_dentry(dentry);
1310 /*
1311 * - We are holding Fx, which implies Fs caps.
1312 * - Only support async unlink for primary linkage
1313 */
1314 if (atomic_read(&ci->i_shared_gen) != di->lease_shared_gen ||
1315 !(di->flags & CEPH_DENTRY_PRIMARY_LINK))
1316 want = 0;
1317 spin_unlock(&dentry->d_lock);
1318
1319 /* Do we still want what we've got? */
1320 if (want == got)
1321 return got;
1322
1323 ceph_put_cap_refs(ci, got);
1324 return 0;
1325 }
1326
1327 /*
1328 * rmdir and unlink are differ only by the metadata op code
1329 */
ceph_unlink(struct inode * dir,struct dentry * dentry)1330 static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1331 {
1332 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dir->i_sb);
1333 struct ceph_client *cl = fsc->client;
1334 struct ceph_mds_client *mdsc = fsc->mdsc;
1335 struct inode *inode = d_inode(dentry);
1336 struct ceph_mds_request *req;
1337 bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
1338 struct dentry *dn;
1339 int err = -EROFS;
1340 int op;
1341 char *path;
1342 int pathlen;
1343 u64 pathbase;
1344
1345 if (ceph_snap(dir) == CEPH_SNAPDIR) {
1346 /* rmdir .snap/foo is RMSNAP */
1347 doutc(cl, "rmsnap %llx.%llx/'%pd' dn\n", ceph_vinop(dir),
1348 dentry);
1349 op = CEPH_MDS_OP_RMSNAP;
1350 } else if (ceph_snap(dir) == CEPH_NOSNAP) {
1351 doutc(cl, "unlink/rmdir %llx.%llx/'%pd' inode %llx.%llx\n",
1352 ceph_vinop(dir), dentry, ceph_vinop(inode));
1353 op = d_is_dir(dentry) ?
1354 CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1355 } else
1356 goto out;
1357
1358 dn = d_find_alias(dir);
1359 if (!dn) {
1360 try_async = false;
1361 } else {
1362 path = ceph_mdsc_build_path(mdsc, dn, &pathlen, &pathbase, 0);
1363 if (IS_ERR(path)) {
1364 try_async = false;
1365 err = 0;
1366 } else {
1367 err = ceph_mds_check_access(mdsc, path, MAY_WRITE);
1368 }
1369 ceph_mdsc_free_path(path, pathlen);
1370 dput(dn);
1371
1372 /* For none EACCES cases will let the MDS do the mds auth check */
1373 if (err == -EACCES) {
1374 return err;
1375 } else if (err < 0) {
1376 try_async = false;
1377 err = 0;
1378 }
1379 }
1380
1381 retry:
1382 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1383 if (IS_ERR(req)) {
1384 err = PTR_ERR(req);
1385 goto out;
1386 }
1387 req->r_dentry = dget(dentry);
1388 req->r_num_caps = 2;
1389 req->r_parent = dir;
1390 ihold(dir);
1391 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1392 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1393 req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1394
1395 if (try_async && op == CEPH_MDS_OP_UNLINK &&
1396 (req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) {
1397 struct ceph_dentry_info *di = ceph_dentry(dentry);
1398
1399 doutc(cl, "async unlink on %llx.%llx/'%pd' caps=%s",
1400 ceph_vinop(dir), dentry,
1401 ceph_cap_string(req->r_dir_caps));
1402 set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
1403 req->r_callback = ceph_async_unlink_cb;
1404 req->r_old_inode = d_inode(dentry);
1405 ihold(req->r_old_inode);
1406
1407 spin_lock(&dentry->d_lock);
1408 di->flags |= CEPH_DENTRY_ASYNC_UNLINK;
1409 spin_unlock(&dentry->d_lock);
1410
1411 spin_lock(&fsc->async_unlink_conflict_lock);
1412 hash_add_rcu(fsc->async_unlink_conflict, &di->hnode,
1413 dentry->d_name.hash);
1414 spin_unlock(&fsc->async_unlink_conflict_lock);
1415
1416 err = ceph_mdsc_submit_request(mdsc, dir, req);
1417 if (!err) {
1418 /*
1419 * We have enough caps, so we assume that the unlink
1420 * will succeed. Fix up the target inode and dcache.
1421 */
1422 drop_nlink(inode);
1423 d_delete(dentry);
1424 } else {
1425 spin_lock(&fsc->async_unlink_conflict_lock);
1426 hash_del_rcu(&di->hnode);
1427 spin_unlock(&fsc->async_unlink_conflict_lock);
1428
1429 spin_lock(&dentry->d_lock);
1430 di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1431 spin_unlock(&dentry->d_lock);
1432
1433 if (err == -EJUKEBOX) {
1434 try_async = false;
1435 ceph_mdsc_put_request(req);
1436 goto retry;
1437 }
1438 }
1439 } else {
1440 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1441 err = ceph_mdsc_do_request(mdsc, dir, req);
1442 if (!err && !req->r_reply_info.head->is_dentry)
1443 d_delete(dentry);
1444 }
1445
1446 ceph_mdsc_put_request(req);
1447 out:
1448 return err;
1449 }
1450
ceph_rename(struct mnt_idmap * idmap,struct inode * old_dir,struct dentry * old_dentry,struct inode * new_dir,struct dentry * new_dentry,unsigned int flags)1451 static int ceph_rename(struct mnt_idmap *idmap, struct inode *old_dir,
1452 struct dentry *old_dentry, struct inode *new_dir,
1453 struct dentry *new_dentry, unsigned int flags)
1454 {
1455 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old_dir->i_sb);
1456 struct ceph_client *cl = mdsc->fsc->client;
1457 struct ceph_mds_request *req;
1458 int op = CEPH_MDS_OP_RENAME;
1459 int err;
1460
1461 if (flags)
1462 return -EINVAL;
1463
1464 if (ceph_snap(old_dir) != ceph_snap(new_dir))
1465 return -EXDEV;
1466 if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1467 if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1468 op = CEPH_MDS_OP_RENAMESNAP;
1469 else
1470 return -EROFS;
1471 }
1472 /* don't allow cross-quota renames */
1473 if ((old_dir != new_dir) &&
1474 (!ceph_quota_is_same_realm(old_dir, new_dir)))
1475 return -EXDEV;
1476
1477 err = ceph_wait_on_conflict_unlink(new_dentry);
1478 if (err)
1479 return err;
1480
1481 err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
1482 flags);
1483 if (err)
1484 return err;
1485
1486 doutc(cl, "%llx.%llx/'%pd' to %llx.%llx/'%pd'\n",
1487 ceph_vinop(old_dir), old_dentry, ceph_vinop(new_dir),
1488 new_dentry);
1489 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1490 if (IS_ERR(req))
1491 return PTR_ERR(req);
1492 ihold(old_dir);
1493 req->r_dentry = dget(new_dentry);
1494 req->r_num_caps = 2;
1495 req->r_old_dentry = dget(old_dentry);
1496 req->r_old_dentry_dir = old_dir;
1497 req->r_parent = new_dir;
1498 ihold(new_dir);
1499 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1500 req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1501 req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1502 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1503 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1504 /* release LINK_RDCACHE on source inode (mds will lock it) */
1505 req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1506 if (d_really_is_positive(new_dentry)) {
1507 req->r_inode_drop =
1508 ceph_drop_caps_for_unlink(d_inode(new_dentry));
1509 }
1510 err = ceph_mdsc_do_request(mdsc, old_dir, req);
1511 if (!err && !req->r_reply_info.head->is_dentry) {
1512 /*
1513 * Normally d_move() is done by fill_trace (called by
1514 * do_request, above). If there is no trace, we need
1515 * to do it here.
1516 */
1517 d_move(old_dentry, new_dentry);
1518 }
1519 ceph_mdsc_put_request(req);
1520 return err;
1521 }
1522
1523 /*
1524 * Move dentry to tail of mdsc->dentry_leases list when lease is updated.
1525 * Leases at front of the list will expire first. (Assume all leases have
1526 * similar duration)
1527 *
1528 * Called under dentry->d_lock.
1529 */
__ceph_dentry_lease_touch(struct ceph_dentry_info * di)1530 void __ceph_dentry_lease_touch(struct ceph_dentry_info *di)
1531 {
1532 struct dentry *dn = di->dentry;
1533 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dn->d_sb)->mdsc;
1534 struct ceph_client *cl = mdsc->fsc->client;
1535
1536 doutc(cl, "%p %p '%pd'\n", di, dn, dn);
1537
1538 di->flags |= CEPH_DENTRY_LEASE_LIST;
1539 if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1540 di->flags |= CEPH_DENTRY_REFERENCED;
1541 return;
1542 }
1543
1544 spin_lock(&mdsc->dentry_list_lock);
1545 list_move_tail(&di->lease_list, &mdsc->dentry_leases);
1546 spin_unlock(&mdsc->dentry_list_lock);
1547 }
1548
__dentry_dir_lease_touch(struct ceph_mds_client * mdsc,struct ceph_dentry_info * di)1549 static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc,
1550 struct ceph_dentry_info *di)
1551 {
1552 di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED);
1553 di->lease_gen = 0;
1554 di->time = jiffies;
1555 list_move_tail(&di->lease_list, &mdsc->dentry_dir_leases);
1556 }
1557
1558 /*
1559 * When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases
1560 * list if it's not in the list, otherwise set 'referenced' flag.
1561 *
1562 * Called under dentry->d_lock.
1563 */
__ceph_dentry_dir_lease_touch(struct ceph_dentry_info * di)1564 void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di)
1565 {
1566 struct dentry *dn = di->dentry;
1567 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dn->d_sb)->mdsc;
1568 struct ceph_client *cl = mdsc->fsc->client;
1569
1570 doutc(cl, "%p %p '%pd' (offset 0x%llx)\n", di, dn, dn, di->offset);
1571
1572 if (!list_empty(&di->lease_list)) {
1573 if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1574 /* don't remove dentry from dentry lease list
1575 * if its lease is valid */
1576 if (__dentry_lease_is_valid(di))
1577 return;
1578 } else {
1579 di->flags |= CEPH_DENTRY_REFERENCED;
1580 return;
1581 }
1582 }
1583
1584 if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1585 di->flags |= CEPH_DENTRY_REFERENCED;
1586 di->flags &= ~CEPH_DENTRY_LEASE_LIST;
1587 return;
1588 }
1589
1590 spin_lock(&mdsc->dentry_list_lock);
1591 __dentry_dir_lease_touch(mdsc, di);
1592 spin_unlock(&mdsc->dentry_list_lock);
1593 }
1594
__dentry_lease_unlist(struct ceph_dentry_info * di)1595 static void __dentry_lease_unlist(struct ceph_dentry_info *di)
1596 {
1597 struct ceph_mds_client *mdsc;
1598 if (di->flags & CEPH_DENTRY_SHRINK_LIST)
1599 return;
1600 if (list_empty(&di->lease_list))
1601 return;
1602
1603 mdsc = ceph_sb_to_fs_client(di->dentry->d_sb)->mdsc;
1604 spin_lock(&mdsc->dentry_list_lock);
1605 list_del_init(&di->lease_list);
1606 spin_unlock(&mdsc->dentry_list_lock);
1607 }
1608
1609 enum {
1610 KEEP = 0,
1611 DELETE = 1,
1612 TOUCH = 2,
1613 STOP = 4,
1614 };
1615
1616 struct ceph_lease_walk_control {
1617 bool dir_lease;
1618 bool expire_dir_lease;
1619 unsigned long nr_to_scan;
1620 unsigned long dir_lease_ttl;
1621 };
1622
1623 static int __dir_lease_check(const struct dentry *, struct ceph_lease_walk_control *);
1624 static int __dentry_lease_check(const struct dentry *);
1625
1626 static unsigned long
__dentry_leases_walk(struct ceph_mds_client * mdsc,struct ceph_lease_walk_control * lwc)1627 __dentry_leases_walk(struct ceph_mds_client *mdsc,
1628 struct ceph_lease_walk_control *lwc)
1629 {
1630 struct ceph_dentry_info *di, *tmp;
1631 struct dentry *dentry, *last = NULL;
1632 struct list_head* list;
1633 LIST_HEAD(dispose);
1634 unsigned long freed = 0;
1635 int ret = 0;
1636
1637 list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases;
1638 spin_lock(&mdsc->dentry_list_lock);
1639 list_for_each_entry_safe(di, tmp, list, lease_list) {
1640 if (!lwc->nr_to_scan)
1641 break;
1642 --lwc->nr_to_scan;
1643
1644 dentry = di->dentry;
1645 if (last == dentry)
1646 break;
1647
1648 if (!spin_trylock(&dentry->d_lock))
1649 continue;
1650
1651 if (__lockref_is_dead(&dentry->d_lockref)) {
1652 list_del_init(&di->lease_list);
1653 goto next;
1654 }
1655
1656 if (lwc->dir_lease)
1657 ret = __dir_lease_check(dentry, lwc);
1658 else
1659 ret = __dentry_lease_check(dentry);
1660 if (ret & TOUCH) {
1661 /* move it into tail of dir lease list */
1662 __dentry_dir_lease_touch(mdsc, di);
1663 if (!last)
1664 last = dentry;
1665 }
1666 if (ret & DELETE) {
1667 /* stale lease */
1668 di->flags &= ~CEPH_DENTRY_REFERENCED;
1669 if (dentry->d_lockref.count > 0) {
1670 /* update_dentry_lease() will re-add
1671 * it to lease list, or
1672 * ceph_d_delete() will return 1 when
1673 * last reference is dropped */
1674 list_del_init(&di->lease_list);
1675 } else {
1676 di->flags |= CEPH_DENTRY_SHRINK_LIST;
1677 list_move_tail(&di->lease_list, &dispose);
1678 dget_dlock(dentry);
1679 }
1680 }
1681 next:
1682 spin_unlock(&dentry->d_lock);
1683 if (ret & STOP)
1684 break;
1685 }
1686 spin_unlock(&mdsc->dentry_list_lock);
1687
1688 while (!list_empty(&dispose)) {
1689 di = list_first_entry(&dispose, struct ceph_dentry_info,
1690 lease_list);
1691 dentry = di->dentry;
1692 spin_lock(&dentry->d_lock);
1693
1694 list_del_init(&di->lease_list);
1695 di->flags &= ~CEPH_DENTRY_SHRINK_LIST;
1696 if (di->flags & CEPH_DENTRY_REFERENCED) {
1697 spin_lock(&mdsc->dentry_list_lock);
1698 if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1699 list_add_tail(&di->lease_list,
1700 &mdsc->dentry_leases);
1701 } else {
1702 __dentry_dir_lease_touch(mdsc, di);
1703 }
1704 spin_unlock(&mdsc->dentry_list_lock);
1705 } else {
1706 freed++;
1707 }
1708
1709 spin_unlock(&dentry->d_lock);
1710 /* ceph_d_delete() does the trick */
1711 dput(dentry);
1712 }
1713 return freed;
1714 }
1715
__dentry_lease_check(const struct dentry * dentry)1716 static int __dentry_lease_check(const struct dentry *dentry)
1717 {
1718 struct ceph_dentry_info *di = ceph_dentry(dentry);
1719 int ret;
1720
1721 if (__dentry_lease_is_valid(di))
1722 return STOP;
1723 ret = __dir_lease_try_check(dentry);
1724 if (ret == -EBUSY)
1725 return KEEP;
1726 if (ret > 0)
1727 return TOUCH;
1728 return DELETE;
1729 }
1730
__dir_lease_check(const struct dentry * dentry,struct ceph_lease_walk_control * lwc)1731 static int __dir_lease_check(const struct dentry *dentry,
1732 struct ceph_lease_walk_control *lwc)
1733 {
1734 struct ceph_dentry_info *di = ceph_dentry(dentry);
1735
1736 int ret = __dir_lease_try_check(dentry);
1737 if (ret == -EBUSY)
1738 return KEEP;
1739 if (ret > 0) {
1740 if (time_before(jiffies, di->time + lwc->dir_lease_ttl))
1741 return STOP;
1742 /* Move dentry to tail of dir lease list if we don't want
1743 * to delete it. So dentries in the list are checked in a
1744 * round robin manner */
1745 if (!lwc->expire_dir_lease)
1746 return TOUCH;
1747 if (dentry->d_lockref.count > 0 ||
1748 (di->flags & CEPH_DENTRY_REFERENCED))
1749 return TOUCH;
1750 /* invalidate dir lease */
1751 di->lease_shared_gen = 0;
1752 }
1753 return DELETE;
1754 }
1755
ceph_trim_dentries(struct ceph_mds_client * mdsc)1756 int ceph_trim_dentries(struct ceph_mds_client *mdsc)
1757 {
1758 struct ceph_lease_walk_control lwc;
1759 unsigned long count;
1760 unsigned long freed;
1761
1762 spin_lock(&mdsc->caps_list_lock);
1763 if (mdsc->caps_use_max > 0 &&
1764 mdsc->caps_use_count > mdsc->caps_use_max)
1765 count = mdsc->caps_use_count - mdsc->caps_use_max;
1766 else
1767 count = 0;
1768 spin_unlock(&mdsc->caps_list_lock);
1769
1770 lwc.dir_lease = false;
1771 lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE * 2;
1772 freed = __dentry_leases_walk(mdsc, &lwc);
1773 if (!lwc.nr_to_scan) /* more invalid leases */
1774 return -EAGAIN;
1775
1776 if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE)
1777 lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE;
1778
1779 lwc.dir_lease = true;
1780 lwc.expire_dir_lease = freed < count;
1781 lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ;
1782 freed +=__dentry_leases_walk(mdsc, &lwc);
1783 if (!lwc.nr_to_scan) /* more to check */
1784 return -EAGAIN;
1785
1786 return freed > 0 ? 1 : 0;
1787 }
1788
1789 /*
1790 * Ensure a dentry lease will no longer revalidate.
1791 */
ceph_invalidate_dentry_lease(struct dentry * dentry)1792 void ceph_invalidate_dentry_lease(struct dentry *dentry)
1793 {
1794 struct ceph_dentry_info *di = ceph_dentry(dentry);
1795 spin_lock(&dentry->d_lock);
1796 di->time = jiffies;
1797 di->lease_shared_gen = 0;
1798 di->flags &= ~CEPH_DENTRY_PRIMARY_LINK;
1799 __dentry_lease_unlist(di);
1800 spin_unlock(&dentry->d_lock);
1801 }
1802
1803 /*
1804 * Check if dentry lease is valid. If not, delete the lease. Try to
1805 * renew if the least is more than half up.
1806 */
__dentry_lease_is_valid(struct ceph_dentry_info * di)1807 static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)
1808 {
1809 struct ceph_mds_session *session;
1810
1811 if (!di->lease_gen)
1812 return false;
1813
1814 session = di->lease_session;
1815 if (session) {
1816 u32 gen;
1817 unsigned long ttl;
1818
1819 gen = atomic_read(&session->s_cap_gen);
1820 ttl = session->s_cap_ttl;
1821
1822 if (di->lease_gen == gen &&
1823 time_before(jiffies, ttl) &&
1824 time_before(jiffies, di->time))
1825 return true;
1826 }
1827 di->lease_gen = 0;
1828 return false;
1829 }
1830
dentry_lease_is_valid(struct dentry * dentry,unsigned int flags)1831 static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)
1832 {
1833 struct ceph_dentry_info *di;
1834 struct ceph_mds_session *session = NULL;
1835 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dentry->d_sb)->mdsc;
1836 struct ceph_client *cl = mdsc->fsc->client;
1837 u32 seq = 0;
1838 int valid = 0;
1839
1840 spin_lock(&dentry->d_lock);
1841 di = ceph_dentry(dentry);
1842 if (di && __dentry_lease_is_valid(di)) {
1843 valid = 1;
1844
1845 if (di->lease_renew_after &&
1846 time_after(jiffies, di->lease_renew_after)) {
1847 /*
1848 * We should renew. If we're in RCU walk mode
1849 * though, we can't do that so just return
1850 * -ECHILD.
1851 */
1852 if (flags & LOOKUP_RCU) {
1853 valid = -ECHILD;
1854 } else {
1855 session = ceph_get_mds_session(di->lease_session);
1856 seq = di->lease_seq;
1857 di->lease_renew_after = 0;
1858 di->lease_renew_from = jiffies;
1859 }
1860 }
1861 }
1862 spin_unlock(&dentry->d_lock);
1863
1864 if (session) {
1865 ceph_mdsc_lease_send_msg(session, dentry,
1866 CEPH_MDS_LEASE_RENEW, seq);
1867 ceph_put_mds_session(session);
1868 }
1869 doutc(cl, "dentry %p = %d\n", dentry, valid);
1870 return valid;
1871 }
1872
1873 /*
1874 * Called under dentry->d_lock.
1875 */
__dir_lease_try_check(const struct dentry * dentry)1876 static int __dir_lease_try_check(const struct dentry *dentry)
1877 {
1878 struct ceph_dentry_info *di = ceph_dentry(dentry);
1879 struct inode *dir;
1880 struct ceph_inode_info *ci;
1881 int valid = 0;
1882
1883 if (!di->lease_shared_gen)
1884 return 0;
1885 if (IS_ROOT(dentry))
1886 return 0;
1887
1888 dir = d_inode(dentry->d_parent);
1889 ci = ceph_inode(dir);
1890
1891 if (spin_trylock(&ci->i_ceph_lock)) {
1892 if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen &&
1893 __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 0))
1894 valid = 1;
1895 spin_unlock(&ci->i_ceph_lock);
1896 } else {
1897 valid = -EBUSY;
1898 }
1899
1900 if (!valid)
1901 di->lease_shared_gen = 0;
1902 return valid;
1903 }
1904
1905 /*
1906 * Check if directory-wide content lease/cap is valid.
1907 */
dir_lease_is_valid(struct inode * dir,struct dentry * dentry,struct ceph_mds_client * mdsc)1908 static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry,
1909 struct ceph_mds_client *mdsc)
1910 {
1911 struct ceph_inode_info *ci = ceph_inode(dir);
1912 struct ceph_client *cl = mdsc->fsc->client;
1913 int valid;
1914 int shared_gen;
1915
1916 spin_lock(&ci->i_ceph_lock);
1917 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1918 if (valid) {
1919 __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
1920 shared_gen = atomic_read(&ci->i_shared_gen);
1921 }
1922 spin_unlock(&ci->i_ceph_lock);
1923 if (valid) {
1924 struct ceph_dentry_info *di;
1925 spin_lock(&dentry->d_lock);
1926 di = ceph_dentry(dentry);
1927 if (dir == d_inode(dentry->d_parent) &&
1928 di && di->lease_shared_gen == shared_gen)
1929 __ceph_dentry_dir_lease_touch(di);
1930 else
1931 valid = 0;
1932 spin_unlock(&dentry->d_lock);
1933 }
1934 doutc(cl, "dir %p %llx.%llx v%u dentry %p '%pd' = %d\n", dir,
1935 ceph_vinop(dir), (unsigned)atomic_read(&ci->i_shared_gen),
1936 dentry, dentry, valid);
1937 return valid;
1938 }
1939
1940 /*
1941 * Check if cached dentry can be trusted.
1942 */
ceph_d_revalidate(struct dentry * dentry,unsigned int flags)1943 static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1944 {
1945 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dentry->d_sb)->mdsc;
1946 struct ceph_client *cl = mdsc->fsc->client;
1947 int valid = 0;
1948 struct dentry *parent;
1949 struct inode *dir, *inode;
1950
1951 valid = fscrypt_d_revalidate(dentry, flags);
1952 if (valid <= 0)
1953 return valid;
1954
1955 if (flags & LOOKUP_RCU) {
1956 parent = READ_ONCE(dentry->d_parent);
1957 dir = d_inode_rcu(parent);
1958 if (!dir)
1959 return -ECHILD;
1960 inode = d_inode_rcu(dentry);
1961 } else {
1962 parent = dget_parent(dentry);
1963 dir = d_inode(parent);
1964 inode = d_inode(dentry);
1965 }
1966
1967 doutc(cl, "%p '%pd' inode %p offset 0x%llx nokey %d\n",
1968 dentry, dentry, inode, ceph_dentry(dentry)->offset,
1969 !!(dentry->d_flags & DCACHE_NOKEY_NAME));
1970
1971 mdsc = ceph_sb_to_fs_client(dir->i_sb)->mdsc;
1972
1973 /* always trust cached snapped dentries, snapdir dentry */
1974 if (ceph_snap(dir) != CEPH_NOSNAP) {
1975 doutc(cl, "%p '%pd' inode %p is SNAPPED\n", dentry,
1976 dentry, inode);
1977 valid = 1;
1978 } else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1979 valid = 1;
1980 } else {
1981 valid = dentry_lease_is_valid(dentry, flags);
1982 if (valid == -ECHILD)
1983 return valid;
1984 if (valid || dir_lease_is_valid(dir, dentry, mdsc)) {
1985 if (inode)
1986 valid = ceph_is_any_caps(inode);
1987 else
1988 valid = 1;
1989 }
1990 }
1991
1992 if (!valid) {
1993 struct ceph_mds_request *req;
1994 int op, err;
1995 u32 mask;
1996
1997 if (flags & LOOKUP_RCU)
1998 return -ECHILD;
1999
2000 percpu_counter_inc(&mdsc->metric.d_lease_mis);
2001
2002 op = ceph_snap(dir) == CEPH_SNAPDIR ?
2003 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
2004 req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
2005 if (!IS_ERR(req)) {
2006 req->r_dentry = dget(dentry);
2007 req->r_num_caps = 2;
2008 req->r_parent = dir;
2009 ihold(dir);
2010
2011 mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
2012 if (ceph_security_xattr_wanted(dir))
2013 mask |= CEPH_CAP_XATTR_SHARED;
2014 req->r_args.getattr.mask = cpu_to_le32(mask);
2015
2016 err = ceph_mdsc_do_request(mdsc, NULL, req);
2017 switch (err) {
2018 case 0:
2019 if (d_really_is_positive(dentry) &&
2020 d_inode(dentry) == req->r_target_inode)
2021 valid = 1;
2022 break;
2023 case -ENOENT:
2024 if (d_really_is_negative(dentry))
2025 valid = 1;
2026 fallthrough;
2027 default:
2028 break;
2029 }
2030 ceph_mdsc_put_request(req);
2031 doutc(cl, "%p '%pd', lookup result=%d\n", dentry,
2032 dentry, err);
2033 }
2034 } else {
2035 percpu_counter_inc(&mdsc->metric.d_lease_hit);
2036 }
2037
2038 doutc(cl, "%p '%pd' %s\n", dentry, dentry, valid ? "valid" : "invalid");
2039 if (!valid)
2040 ceph_dir_clear_complete(dir);
2041
2042 if (!(flags & LOOKUP_RCU))
2043 dput(parent);
2044 return valid;
2045 }
2046
2047 /*
2048 * Delete unused dentry that doesn't have valid lease
2049 *
2050 * Called under dentry->d_lock.
2051 */
ceph_d_delete(const struct dentry * dentry)2052 static int ceph_d_delete(const struct dentry *dentry)
2053 {
2054 struct ceph_dentry_info *di;
2055
2056 /* won't release caps */
2057 if (d_really_is_negative(dentry))
2058 return 0;
2059 if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
2060 return 0;
2061 /* valid lease? */
2062 di = ceph_dentry(dentry);
2063 if (di) {
2064 if (__dentry_lease_is_valid(di))
2065 return 0;
2066 if (__dir_lease_try_check(dentry))
2067 return 0;
2068 }
2069 return 1;
2070 }
2071
2072 /*
2073 * Release our ceph_dentry_info.
2074 */
ceph_d_release(struct dentry * dentry)2075 static void ceph_d_release(struct dentry *dentry)
2076 {
2077 struct ceph_dentry_info *di = ceph_dentry(dentry);
2078 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);
2079
2080 doutc(fsc->client, "dentry %p '%pd'\n", dentry, dentry);
2081
2082 atomic64_dec(&fsc->mdsc->metric.total_dentries);
2083
2084 spin_lock(&dentry->d_lock);
2085 __dentry_lease_unlist(di);
2086 dentry->d_fsdata = NULL;
2087 spin_unlock(&dentry->d_lock);
2088
2089 ceph_put_mds_session(di->lease_session);
2090 kmem_cache_free(ceph_dentry_cachep, di);
2091 }
2092
2093 /*
2094 * When the VFS prunes a dentry from the cache, we need to clear the
2095 * complete flag on the parent directory.
2096 *
2097 * Called under dentry->d_lock.
2098 */
ceph_d_prune(struct dentry * dentry)2099 static void ceph_d_prune(struct dentry *dentry)
2100 {
2101 struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);
2102 struct ceph_client *cl = mdsc->fsc->client;
2103 struct ceph_inode_info *dir_ci;
2104 struct ceph_dentry_info *di;
2105
2106 doutc(cl, "dentry %p '%pd'\n", dentry, dentry);
2107
2108 /* do we have a valid parent? */
2109 if (IS_ROOT(dentry))
2110 return;
2111
2112 /* we hold d_lock, so d_parent is stable */
2113 dir_ci = ceph_inode(d_inode(dentry->d_parent));
2114 if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
2115 return;
2116
2117 /* who calls d_delete() should also disable dcache readdir */
2118 if (d_really_is_negative(dentry))
2119 return;
2120
2121 /* d_fsdata does not get cleared until d_release */
2122 if (!d_unhashed(dentry)) {
2123 __ceph_dir_clear_complete(dir_ci);
2124 return;
2125 }
2126
2127 /* Disable dcache readdir just in case that someone called d_drop()
2128 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
2129 * properly (dcache readdir is still enabled) */
2130 di = ceph_dentry(dentry);
2131 if (di->offset > 0 &&
2132 di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
2133 __ceph_dir_clear_ordered(dir_ci);
2134 }
2135
2136 /*
2137 * read() on a dir. This weird interface hack only works if mounted
2138 * with '-o dirstat'.
2139 */
ceph_read_dir(struct file * file,char __user * buf,size_t size,loff_t * ppos)2140 static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
2141 loff_t *ppos)
2142 {
2143 struct ceph_dir_file_info *dfi = file->private_data;
2144 struct inode *inode = file_inode(file);
2145 struct ceph_inode_info *ci = ceph_inode(inode);
2146 int left;
2147 const int bufsize = 1024;
2148
2149 if (!ceph_test_mount_opt(ceph_sb_to_fs_client(inode->i_sb), DIRSTAT))
2150 return -EISDIR;
2151
2152 if (!dfi->dir_info) {
2153 dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
2154 if (!dfi->dir_info)
2155 return -ENOMEM;
2156 dfi->dir_info_len =
2157 snprintf(dfi->dir_info, bufsize,
2158 "entries: %20lld\n"
2159 " files: %20lld\n"
2160 " subdirs: %20lld\n"
2161 "rentries: %20lld\n"
2162 " rfiles: %20lld\n"
2163 " rsubdirs: %20lld\n"
2164 "rbytes: %20lld\n"
2165 "rctime: %10lld.%09ld\n",
2166 ci->i_files + ci->i_subdirs,
2167 ci->i_files,
2168 ci->i_subdirs,
2169 ci->i_rfiles + ci->i_rsubdirs,
2170 ci->i_rfiles,
2171 ci->i_rsubdirs,
2172 ci->i_rbytes,
2173 ci->i_rctime.tv_sec,
2174 ci->i_rctime.tv_nsec);
2175 }
2176
2177 if (*ppos >= dfi->dir_info_len)
2178 return 0;
2179 size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
2180 left = copy_to_user(buf, dfi->dir_info + *ppos, size);
2181 if (left == size)
2182 return -EFAULT;
2183 *ppos += (size - left);
2184 return size - left;
2185 }
2186
2187
2188
2189 /*
2190 * Return name hash for a given dentry. This is dependent on
2191 * the parent directory's hash function.
2192 */
ceph_dentry_hash(struct inode * dir,struct dentry * dn)2193 unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
2194 {
2195 struct ceph_inode_info *dci = ceph_inode(dir);
2196 unsigned hash;
2197
2198 switch (dci->i_dir_layout.dl_dir_hash) {
2199 case 0: /* for backward compat */
2200 case CEPH_STR_HASH_LINUX:
2201 return dn->d_name.hash;
2202
2203 default:
2204 spin_lock(&dn->d_lock);
2205 hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
2206 dn->d_name.name, dn->d_name.len);
2207 spin_unlock(&dn->d_lock);
2208 return hash;
2209 }
2210 }
2211
2212 WRAP_DIR_ITER(ceph_readdir) // FIXME!
2213 const struct file_operations ceph_dir_fops = {
2214 .read = ceph_read_dir,
2215 .iterate_shared = shared_ceph_readdir,
2216 .llseek = ceph_dir_llseek,
2217 .open = ceph_open,
2218 .release = ceph_release,
2219 .unlocked_ioctl = ceph_ioctl,
2220 .compat_ioctl = compat_ptr_ioctl,
2221 .fsync = ceph_fsync,
2222 .lock = ceph_lock,
2223 .flock = ceph_flock,
2224 };
2225
2226 const struct file_operations ceph_snapdir_fops = {
2227 .iterate_shared = shared_ceph_readdir,
2228 .llseek = ceph_dir_llseek,
2229 .open = ceph_open,
2230 .release = ceph_release,
2231 };
2232
2233 const struct inode_operations ceph_dir_iops = {
2234 .lookup = ceph_lookup,
2235 .permission = ceph_permission,
2236 .getattr = ceph_getattr,
2237 .setattr = ceph_setattr,
2238 .listxattr = ceph_listxattr,
2239 .get_inode_acl = ceph_get_acl,
2240 .set_acl = ceph_set_acl,
2241 .mknod = ceph_mknod,
2242 .symlink = ceph_symlink,
2243 .mkdir = ceph_mkdir,
2244 .link = ceph_link,
2245 .unlink = ceph_unlink,
2246 .rmdir = ceph_unlink,
2247 .rename = ceph_rename,
2248 .create = ceph_create,
2249 .atomic_open = ceph_atomic_open,
2250 };
2251
2252 const struct inode_operations ceph_snapdir_iops = {
2253 .lookup = ceph_lookup,
2254 .permission = ceph_permission,
2255 .getattr = ceph_getattr,
2256 .mkdir = ceph_mkdir,
2257 .rmdir = ceph_unlink,
2258 .rename = ceph_rename,
2259 };
2260
2261 const struct dentry_operations ceph_dentry_ops = {
2262 .d_revalidate = ceph_d_revalidate,
2263 .d_delete = ceph_d_delete,
2264 .d_release = ceph_d_release,
2265 .d_prune = ceph_d_prune,
2266 .d_init = ceph_d_init,
2267 };
2268