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	*/
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(sb: dentry->d_sb);
43
44	di = kmem_cache_zalloc(k: 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(list: &di->lease_list);
53
54	atomic64_inc(v: &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))
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
78	static bool is_hash_order(loff_t p)
79	{
80	return (p & HASH_ORDER) == HASH_ORDER;
81	}
82
83	static unsigned fpos_frag(loff_t p)
84	{
85	return p >> OFFSET_BITS;
86	}
87
88	static unsigned fpos_hash(loff_t p)
89	{
90	return ceph_frag_value(f: fpos_frag(p));
91	}
92
93	static unsigned fpos_off(loff_t p)
94	{
95	return p & OFFSET_MASK;
96	}
97
98	static int fpos_cmp(loff_t l, loff_t r)
99	{
100	int v = ceph_frag_compare(a: fpos_frag(p: l), b: fpos_frag(p: r));
101	if (v)
102	return v;
103	return (int)(fpos_off(p: l) - fpos_off(p: 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	*/
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(size: len+1, GFP_KERNEL);
118	if (!buf)
119	return -ENOMEM;
120	kfree(objp: 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 *
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(dentry: parent);
135	struct ceph_client *cl = ceph_inode_to_client(inode: 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(inode: dir))
142	return NULL;
143
144	if (!cache_ctl->page || ptr_pgoff != page_index(page: cache_ctl->page)) {
145	ceph_readdir_cache_release(ctl: cache_ctl);
146	cache_ctl->page = find_lock_page(mapping: &dir->i_data, index: ptr_pgoff);
147	if (!cache_ctl->page) {
148	doutc(cl, " page %lu not found\n", ptr_pgoff);
149	return ERR_PTR(error: -EAGAIN);
150	}
151	/* reading/filling the cache are serialized by
152	i_rwsem, no need to use page lock */
153	unlock_page(page: cache_ctl->page);
154	cache_ctl->dentries = kmap(page: cache_ctl->page);
155	}
156
157	cache_ctl->index = idx & idx_mask;
158
159	rcu_read_lock();
160	spin_lock(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(inode: dir) && ptr_pos < i_size_read(inode: dir))
164	dentry = cache_ctl->dentries[cache_ctl->index];
165	else
166	dentry = NULL;
167	spin_unlock(lock: &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(error: -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	*/
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(dentry: parent);
191	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode: dir);
192	struct ceph_client *cl = ceph_inode_to_client(inode: 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(dividend: i_size_read(inode: dir), divisor: sizeof(struct dentry *));
205	while (count > 0) {
206	u64 step = count >> 1;
207	dentry = __dcache_find_get_entry(parent, idx: idx + step,
208	cache_ctl: &cache_ctl);
209	if (!dentry) {
210	/* use linar search */
211	idx = 0;
212	break;
213	}
214	if (IS_ERR(ptr: dentry)) {
215	err = PTR_ERR(ptr: dentry);
216	goto out;
217	}
218	di = ceph_dentry(dentry);
219	spin_lock(lock: &dentry->d_lock);
220	if (fpos_cmp(l: di->offset, r: ctx->pos) < 0) {
221	idx += step + 1;
222	count -= step + 1;
223	} else {
224	count = step;
225	}
226	spin_unlock(lock: &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: idx++, cache_ctl: &cache_ctl);
238	if (!dentry) {
239	dfi->file_info.flags |= CEPH_F_ATEND;
240	err = 0;
241	break;
242	}
243	if (IS_ERR(ptr: dentry)) {
244	err = PTR_ERR(ptr: dentry);
245	goto out;
246	}
247
248	spin_lock(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(inode: dir))) {
255	spin_unlock(lock: &dentry->d_lock);
256	dput(dentry);
257	err = -EAGAIN;
258	goto out;
259	}
260	if (fpos_cmp(l: ctx->pos, r: di->offset) <= 0) {
261	__ceph_dentry_dir_lease_touch(di);
262	emit_dentry = true;
263	}
264	spin_unlock(lock: &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, name: dentry->d_name.name,
271	namelen: dentry->d_name.len, ino: ceph_present_inode(inode: d_inode(dentry)),
272	type: 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(ctl: &cache_ctl);
288	if (last) {
289	int ret;
290	di = ceph_dentry(dentry: last);
291	ret = note_last_dentry(fsc, dfi, name: last->d_name.name,
292	len: last->d_name.len,
293	next_offset: fpos_off(p: 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
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(p: pos))
311	return !ceph_frag_contains_value(f: dfi->frag, v: fpos_hash(p: pos));
312	else
313	return dfi->frag != fpos_frag(p: pos);
314	}
315
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(f: 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, name: ".", namelen: 1, ino: ceph_present_inode(inode),
339	type: 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(lock: &dentry->d_lock);
348	ino = ceph_present_inode(inode: dentry->d_parent->d_inode);
349	spin_unlock(lock: &dentry->d_lock);
350
351	doutc(cl, "%p %llx.%llx off 1 -> '..'\n", inode,
352	ceph_vinop(inode));
353	if (!dir_emit(ctx, name: "..", namelen: 2, ino, type: inode->i_mode >> 12))
354	return 0;
355	ctx->pos = 2;
356	}
357
358	err = ceph_fscrypt_prepare_readdir(dir: inode);
359	if (err < 0)
360	return err;
361
362	spin_lock(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, t: 1)) {
372	int shared_gen = atomic_read(v: &ci->i_shared_gen);
373
374	spin_unlock(lock: &ci->i_ceph_lock);
375	err = __dcache_readdir(file, ctx, shared_gen);
376	if (err != -EAGAIN)
377	return err;
378	} else {
379	spin_unlock(lock: &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, pos: 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(req: dfi->last_readdir);
393	dfi->last_readdir = NULL;
394	}
395
396	if (is_hash_order(p: 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, v: fpos_hash(p: ctx->pos),
401	NULL, NULL);
402	} else {
403	frag = fpos_frag(p: 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, mode: USE_AUTH_MDS);
409	if (IS_ERR(ptr: req))
410	return PTR_ERR(ptr: req);
411
412	err = ceph_alloc_readdir_reply_buffer(req, dir: 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(f: 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(parent: inode, d_name: &d_name,
435	buf: req->r_path2);
436	if (err < 0) {
437	ceph_mdsc_put_request(req);
438	return err;
439	}
440	} else if (is_hash_order(p: 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(dentry: 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(high: frag,
475	off: dfi->next_offset,
476	hash_order: 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(f: 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(p: rde->offset) + 1);
510	err = note_last_dentry(fsc, dfi, name: rde->name,
511	len: rde->name_len, next_offset);
512	if (err) {
513	ceph_mdsc_put_request(req: 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, name: rde->name, namelen: rde->name_len,
561	ino: ceph_present_ino(sb: 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(req: 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(f: dfi->frag)) {
587	frag = ceph_frag_next(f: dfi->frag);
588	if (is_hash_order(p: ctx->pos)) {
589	loff_t new_pos = ceph_make_fpos(high: ceph_frag_value(f: frag),
590	off: dfi->next_offset, hash_order: true);
591	if (new_pos > ctx->pos)
592	ctx->pos = new_pos;
593	/* keep last_name */
594	} else {
595	ctx->pos = ceph_make_fpos(high: frag, off: dfi->next_offset,
596	hash_order: false);
597	kfree(objp: 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(v: &ci->i_release_count) ==
612	dfi->dir_release_count) {
613	spin_lock(lock: &ci->i_ceph_lock);
614	if (dfi->dir_ordered_count ==
615	atomic64_read(v: &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, i_size: 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, release_count: dfi->dir_release_count,
628	ordered_count: dfi->dir_ordered_count);
629	spin_unlock(lock: &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
636	static void reset_readdir(struct ceph_dir_file_info *dfi)
637	{
638	if (dfi->last_readdir) {
639	ceph_mdsc_put_request(req: dfi->last_readdir);
640	dfi->last_readdir = NULL;
641	}
642	kfree(objp: 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	*/
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(p: 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(p: 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(p: new_pos) != is_hash_order(p: chunk_offset);
672	}
673
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, new_pos: 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(p: 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	file->f_version = 0;
711	dfi->file_info.flags &= ~CEPH_F_ATEND;
712	}
713	retval = offset;
714	}
715	out:
716	inode_unlock(inode);
717	return retval;
718	}
719
720	/*
721	* Handle lookups for the hidden .snap directory.
722	*/
723	struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
724	struct dentry *dentry)
725	{
726	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb: dentry->d_sb);
727	struct inode *parent = d_inode(dentry: dentry->d_parent); /* we hold i_rwsem */
728	struct ceph_client *cl = ceph_inode_to_client(inode: parent);
729
730	/* .snap dir? */
731	if (ceph_snap(inode: parent) == CEPH_NOSNAP &&
732	strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {
733	struct dentry *res;
734	struct inode *inode = ceph_get_snapdir(parent);
735
736	res = d_splice_alias(inode, dentry);
737	doutc(cl, "ENOENT on snapdir %p '%pd', linking to "
738	"snapdir %p %llx.%llx. Spliced dentry %p\n",
739	dentry, dentry, inode, ceph_vinop(inode), res);
740	if (res)
741	dentry = res;
742	}
743	return dentry;
744	}
745
746	/*
747	* Figure out final result of a lookup/open request.
748	*
749	* Mainly, make sure we return the final req->r_dentry (if it already
750	* existed) in place of the original VFS-provided dentry when they
751	* differ.
752	*
753	* Gracefully handle the case where the MDS replies with -ENOENT and
754	* no trace (which it may do, at its discretion, e.g., if it doesn't
755	* care to issue a lease on the negative dentry).
756	*/
757	struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
758	struct dentry *dentry, int err)
759	{
760	struct ceph_client *cl = req->r_mdsc->fsc->client;
761
762	if (err == -ENOENT) {
763	/* no trace? */
764	err = 0;
765	if (!req->r_reply_info.head->is_dentry) {
766	doutc(cl,
767	"ENOENT and no trace, dentry %p inode %llx.%llx\n",
768	dentry, ceph_vinop(d_inode(dentry)));
769	if (d_really_is_positive(dentry)) {
770	d_drop(dentry);
771	err = -ENOENT;
772	} else {
773	d_add(dentry, NULL);
774	}
775	}
776	}
777	if (err)
778	dentry = ERR_PTR(error: err);
779	else if (dentry != req->r_dentry)
780	dentry = dget(dentry: req->r_dentry); /* we got spliced */
781	else
782	dentry = NULL;
783	return dentry;
784	}
785
786	static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
787	{
788	return ceph_ino(inode) == CEPH_INO_ROOT &&
789	strncmp(dentry->d_name.name, ".ceph", 5) == 0;
790	}
791
792	/*
793	* Look up a single dir entry. If there is a lookup intent, inform
794	* the MDS so that it gets our 'caps wanted' value in a single op.
795	*/
796	static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
797	unsigned int flags)
798	{
799	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb: dir->i_sb);
800	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: dir->i_sb);
801	struct ceph_client *cl = fsc->client;
802	struct ceph_mds_request *req;
803	int op;
804	int mask;
805	int err;
806
807	doutc(cl, "%p %llx.%llx/'%pd' dentry %p\n", dir, ceph_vinop(dir),
808	dentry, dentry);
809
810	if (dentry->d_name.len > NAME_MAX)
811	return ERR_PTR(error: -ENAMETOOLONG);
812
813	if (IS_ENCRYPTED(dir)) {
814	bool had_key = fscrypt_has_encryption_key(inode: dir);
815
816	err = fscrypt_prepare_lookup_partial(dir, dentry);
817	if (err < 0)
818	return ERR_PTR(error: err);
819
820	/* mark directory as incomplete if it has been unlocked */
821	if (!had_key && fscrypt_has_encryption_key(inode: dir))
822	ceph_dir_clear_complete(inode: dir);
823	}
824
825	/* can we conclude ENOENT locally? */
826	if (d_really_is_negative(dentry)) {
827	struct ceph_inode_info *ci = ceph_inode(inode: dir);
828	struct ceph_dentry_info *di = ceph_dentry(dentry);
829
830	spin_lock(lock: &ci->i_ceph_lock);
831	doutc(cl, " dir %llx.%llx flags are 0x%lx\n",
832	ceph_vinop(dir), ci->i_ceph_flags);
833	if (strncmp(dentry->d_name.name,
834	fsc->mount_options->snapdir_name,
835	dentry->d_name.len) &&
836	!is_root_ceph_dentry(inode: dir, dentry) &&
837	ceph_test_mount_opt(fsc, DCACHE) &&
838	__ceph_dir_is_complete(ci) &&
839	__ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, t: 1)) {
840	__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
841	spin_unlock(lock: &ci->i_ceph_lock);
842	doutc(cl, " dir %llx.%llx complete, -ENOENT\n",
843	ceph_vinop(dir));
844	d_add(dentry, NULL);
845	di->lease_shared_gen = atomic_read(v: &ci->i_shared_gen);
846	return NULL;
847	}
848	spin_unlock(lock: &ci->i_ceph_lock);
849	}
850
851	op = ceph_snap(inode: dir) == CEPH_SNAPDIR ?
852	CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
853	req = ceph_mdsc_create_request(mdsc, op, mode: USE_ANY_MDS);
854	if (IS_ERR(ptr: req))
855	return ERR_CAST(ptr: req);
856	req->r_dentry = dget(dentry);
857	req->r_num_caps = 2;
858
859	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
860	if (ceph_security_xattr_wanted(in: dir))
861	mask |= CEPH_CAP_XATTR_SHARED;
862	req->r_args.getattr.mask = cpu_to_le32(mask);
863
864	ihold(inode: dir);
865	req->r_parent = dir;
866	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
867	err = ceph_mdsc_do_request(mdsc, NULL, req);
868	if (err == -ENOENT) {
869	struct dentry *res;
870
871	res = ceph_handle_snapdir(req, dentry);
872	if (IS_ERR(ptr: res)) {
873	err = PTR_ERR(ptr: res);
874	} else {
875	dentry = res;
876	err = 0;
877	}
878	}
879	dentry = ceph_finish_lookup(req, dentry, err);
880	ceph_mdsc_put_request(req); /* will dput(dentry) */
881	doutc(cl, "result=%p\n", dentry);
882	return dentry;
883	}
884
885	/*
886	* If we do a create but get no trace back from the MDS, follow up with
887	* a lookup (the VFS expects us to link up the provided dentry).
888	*/
889	int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
890	{
891	struct dentry *result = ceph_lookup(dir, dentry, flags: 0);
892
893	if (result && !IS_ERR(ptr: result)) {
894	/*
895	* We created the item, then did a lookup, and found
896	* it was already linked to another inode we already
897	* had in our cache (and thus got spliced). To not
898	* confuse VFS (especially when inode is a directory),
899	* we don't link our dentry to that inode, return an
900	* error instead.
901	*
902	* This event should be rare and it happens only when
903	* we talk to old MDS. Recent MDS does not send traceless
904	* reply for request that creates new inode.
905	*/
906	d_drop(dentry: result);
907	return -ESTALE;
908	}
909	return PTR_ERR(ptr: result);
910	}
911
912	static int ceph_mknod(struct mnt_idmap *idmap, struct inode *dir,
913	struct dentry *dentry, umode_t mode, dev_t rdev)
914	{
915	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: dir->i_sb);
916	struct ceph_client *cl = mdsc->fsc->client;
917	struct ceph_mds_request *req;
918	struct ceph_acl_sec_ctx as_ctx = {};
919	int err;
920
921	if (ceph_snap(inode: dir) != CEPH_NOSNAP)
922	return -EROFS;
923
924	err = ceph_wait_on_conflict_unlink(dentry);
925	if (err)
926	return err;
927
928	if (ceph_quota_is_max_files_exceeded(inode: dir)) {
929	err = -EDQUOT;
930	goto out;
931	}
932
933	doutc(cl, "%p %llx.%llx/'%pd' dentry %p mode 0%ho rdev %d\n",
934	dir, ceph_vinop(dir), dentry, dentry, mode, rdev);
935	req = ceph_mdsc_create_request(mdsc, op: CEPH_MDS_OP_MKNOD, mode: USE_AUTH_MDS);
936	if (IS_ERR(ptr: req)) {
937	err = PTR_ERR(ptr: req);
938	goto out;
939	}
940
941	req->r_new_inode = ceph_new_inode(dir, dentry, mode: &mode, as_ctx: &as_ctx);
942	if (IS_ERR(ptr: req->r_new_inode)) {
943	err = PTR_ERR(ptr: req->r_new_inode);
944	req->r_new_inode = NULL;
945	goto out_req;
946	}
947
948	if (S_ISREG(mode) && IS_ENCRYPTED(dir))
949	set_bit(CEPH_MDS_R_FSCRYPT_FILE, addr: &req->r_req_flags);
950
951	req->r_dentry = dget(dentry);
952	req->r_num_caps = 2;
953	req->r_parent = dir;
954	ihold(inode: dir);
955	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
956	req->r_mnt_idmap = mnt_idmap_get(idmap);
957	req->r_args.mknod.mode = cpu_to_le32(mode);
958	req->r_args.mknod.rdev = cpu_to_le32(rdev);
959	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
960	CEPH_CAP_XATTR_EXCL;
961	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
962
963	ceph_as_ctx_to_req(req, as_ctx: &as_ctx);
964
965	err = ceph_mdsc_do_request(mdsc, dir, req);
966	if (!err && !req->r_reply_info.head->is_dentry)
967	err = ceph_handle_notrace_create(dir, dentry);
968	out_req:
969	ceph_mdsc_put_request(req);
970	out:
971	if (!err)
972	ceph_init_inode_acls(inode: d_inode(dentry), as_ctx: &as_ctx);
973	else
974	d_drop(dentry);
975	ceph_release_acl_sec_ctx(as_ctx: &as_ctx);
976	return err;
977	}
978
979	static int ceph_create(struct mnt_idmap *idmap, struct inode *dir,
980	struct dentry *dentry, umode_t mode, bool excl)
981	{
982	return ceph_mknod(idmap, dir, dentry, mode, rdev: 0);
983	}
984
985	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
986	static int prep_encrypted_symlink_target(struct ceph_mds_request *req,
987	const char *dest)
988	{
989	int err;
990	int len = strlen(dest);
991	struct fscrypt_str osd_link = FSTR_INIT(NULL, 0);
992
993	err = fscrypt_prepare_symlink(dir: req->r_parent, target: dest, len, PATH_MAX,
994	disk_link: &osd_link);
995	if (err)
996	goto out;
997
998	err = fscrypt_encrypt_symlink(inode: req->r_new_inode, target: dest, len, disk_link: &osd_link);
999	if (err)
1000	goto out;
1001
1002	req->r_path2 = kmalloc(CEPH_BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL);
1003	if (!req->r_path2) {
1004	err = -ENOMEM;
1005	goto out;
1006	}
1007
1008	len = ceph_base64_encode(src: osd_link.name, srclen: osd_link.len, dst: req->r_path2);
1009	req->r_path2[len] = '\0';
1010	out:
1011	fscrypt_fname_free_buffer(crypto_str: &osd_link);
1012	return err;
1013	}
1014	#else
1015	static int prep_encrypted_symlink_target(struct ceph_mds_request *req,
1016	const char *dest)
1017	{
1018	return -EOPNOTSUPP;
1019	}
1020	#endif
1021
1022	static int ceph_symlink(struct mnt_idmap *idmap, struct inode *dir,
1023	struct dentry *dentry, const char *dest)
1024	{
1025	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: dir->i_sb);
1026	struct ceph_client *cl = mdsc->fsc->client;
1027	struct ceph_mds_request *req;
1028	struct ceph_acl_sec_ctx as_ctx = {};
1029	umode_t mode = S_IFLNK | 0777;
1030	int err;
1031
1032	if (ceph_snap(inode: dir) != CEPH_NOSNAP)
1033	return -EROFS;
1034
1035	err = ceph_wait_on_conflict_unlink(dentry);
1036	if (err)
1037	return err;
1038
1039	if (ceph_quota_is_max_files_exceeded(inode: dir)) {
1040	err = -EDQUOT;
1041	goto out;
1042	}
1043
1044	doutc(cl, "%p %llx.%llx/'%pd' to '%s'\n", dir, ceph_vinop(dir), dentry,
1045	dest);
1046	req = ceph_mdsc_create_request(mdsc, op: CEPH_MDS_OP_SYMLINK, mode: USE_AUTH_MDS);
1047	if (IS_ERR(ptr: req)) {
1048	err = PTR_ERR(ptr: req);
1049	goto out;
1050	}
1051
1052	req->r_new_inode = ceph_new_inode(dir, dentry, mode: &mode, as_ctx: &as_ctx);
1053	if (IS_ERR(ptr: req->r_new_inode)) {
1054	err = PTR_ERR(ptr: req->r_new_inode);
1055	req->r_new_inode = NULL;
1056	goto out_req;
1057	}
1058
1059	req->r_parent = dir;
1060	ihold(inode: dir);
1061
1062	if (IS_ENCRYPTED(req->r_new_inode)) {
1063	err = prep_encrypted_symlink_target(req, dest);
1064	if (err)
1065	goto out_req;
1066	} else {
1067	req->r_path2 = kstrdup(s: dest, GFP_KERNEL);
1068	if (!req->r_path2) {
1069	err = -ENOMEM;
1070	goto out_req;
1071	}
1072	}
1073
1074	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
1075	req->r_mnt_idmap = mnt_idmap_get(idmap);
1076	req->r_dentry = dget(dentry);
1077	req->r_num_caps = 2;
1078	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
1079	CEPH_CAP_XATTR_EXCL;
1080	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1081
1082	ceph_as_ctx_to_req(req, as_ctx: &as_ctx);
1083
1084	err = ceph_mdsc_do_request(mdsc, dir, req);
1085	if (!err && !req->r_reply_info.head->is_dentry)
1086	err = ceph_handle_notrace_create(dir, dentry);
1087	out_req:
1088	ceph_mdsc_put_request(req);
1089	out:
1090	if (err)
1091	d_drop(dentry);
1092	ceph_release_acl_sec_ctx(as_ctx: &as_ctx);
1093	return err;
1094	}
1095
1096	static int ceph_mkdir(struct mnt_idmap *idmap, struct inode *dir,
1097	struct dentry *dentry, umode_t mode)
1098	{
1099	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: dir->i_sb);
1100	struct ceph_client *cl = mdsc->fsc->client;
1101	struct ceph_mds_request *req;
1102	struct ceph_acl_sec_ctx as_ctx = {};
1103	int err;
1104	int op;
1105
1106	err = ceph_wait_on_conflict_unlink(dentry);
1107	if (err)
1108	return err;
1109
1110	if (ceph_snap(inode: dir) == CEPH_SNAPDIR) {
1111	/* mkdir .snap/foo is a MKSNAP */
1112	op = CEPH_MDS_OP_MKSNAP;
1113	doutc(cl, "mksnap %llx.%llx/'%pd' dentry %p\n",
1114	ceph_vinop(dir), dentry, dentry);
1115	} else if (ceph_snap(inode: dir) == CEPH_NOSNAP) {
1116	doutc(cl, "mkdir %llx.%llx/'%pd' dentry %p mode 0%ho\n",
1117	ceph_vinop(dir), dentry, dentry, mode);
1118	op = CEPH_MDS_OP_MKDIR;
1119	} else {
1120	err = -EROFS;
1121	goto out;
1122	}
1123
1124	if (op == CEPH_MDS_OP_MKDIR &&
1125	ceph_quota_is_max_files_exceeded(inode: dir)) {
1126	err = -EDQUOT;
1127	goto out;
1128	}
1129	if ((op == CEPH_MDS_OP_MKSNAP) && IS_ENCRYPTED(dir) &&
1130	!fscrypt_has_encryption_key(inode: dir)) {
1131	err = -ENOKEY;
1132	goto out;
1133	}
1134
1135
1136	req = ceph_mdsc_create_request(mdsc, op, mode: USE_AUTH_MDS);
1137	if (IS_ERR(ptr: req)) {
1138	err = PTR_ERR(ptr: req);
1139	goto out;
1140	}
1141
1142	mode |= S_IFDIR;
1143	req->r_new_inode = ceph_new_inode(dir, dentry, mode: &mode, as_ctx: &as_ctx);
1144	if (IS_ERR(ptr: req->r_new_inode)) {
1145	err = PTR_ERR(ptr: req->r_new_inode);
1146	req->r_new_inode = NULL;
1147	goto out_req;
1148	}
1149
1150	req->r_dentry = dget(dentry);
1151	req->r_num_caps = 2;
1152	req->r_parent = dir;
1153	ihold(inode: dir);
1154	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
1155	if (op == CEPH_MDS_OP_MKDIR)
1156	req->r_mnt_idmap = mnt_idmap_get(idmap);
1157	req->r_args.mkdir.mode = cpu_to_le32(mode);
1158	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |
1159	CEPH_CAP_XATTR_EXCL;
1160	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1161
1162	ceph_as_ctx_to_req(req, as_ctx: &as_ctx);
1163
1164	err = ceph_mdsc_do_request(mdsc, dir, req);
1165	if (!err &&
1166	!req->r_reply_info.head->is_target &&
1167	!req->r_reply_info.head->is_dentry)
1168	err = ceph_handle_notrace_create(dir, dentry);
1169	out_req:
1170	ceph_mdsc_put_request(req);
1171	out:
1172	if (!err)
1173	ceph_init_inode_acls(inode: d_inode(dentry), as_ctx: &as_ctx);
1174	else
1175	d_drop(dentry);
1176	ceph_release_acl_sec_ctx(as_ctx: &as_ctx);
1177	return err;
1178	}
1179
1180	static int ceph_link(struct dentry *old_dentry, struct inode *dir,
1181	struct dentry *dentry)
1182	{
1183	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: dir->i_sb);
1184	struct ceph_client *cl = mdsc->fsc->client;
1185	struct ceph_mds_request *req;
1186	int err;
1187
1188	if (dentry->d_flags & DCACHE_DISCONNECTED)
1189	return -EINVAL;
1190
1191	err = ceph_wait_on_conflict_unlink(dentry);
1192	if (err)
1193	return err;
1194
1195	if (ceph_snap(inode: dir) != CEPH_NOSNAP)
1196	return -EROFS;
1197
1198	err = fscrypt_prepare_link(old_dentry, dir, dentry);
1199	if (err)
1200	return err;
1201
1202	doutc(cl, "%p %llx.%llx/'%pd' to '%pd'\n", dir, ceph_vinop(dir),
1203	old_dentry, dentry);
1204	req = ceph_mdsc_create_request(mdsc, op: CEPH_MDS_OP_LINK, mode: USE_AUTH_MDS);
1205	if (IS_ERR(ptr: req)) {
1206	d_drop(dentry);
1207	return PTR_ERR(ptr: req);
1208	}
1209	req->r_dentry = dget(dentry);
1210	req->r_num_caps = 2;
1211	req->r_old_dentry = dget(dentry: old_dentry);
1212	/*
1213	* The old_dentry maybe a DCACHE_DISCONNECTED dentry, then we
1214	* will just pass the ino# to MDSs.
1215	*/
1216	if (old_dentry->d_flags & DCACHE_DISCONNECTED)
1217	req->r_ino2 = ceph_vino(inode: d_inode(dentry: old_dentry));
1218	req->r_parent = dir;
1219	ihold(inode: dir);
1220	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
1221	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1222	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1223	/* release LINK_SHARED on source inode (mds will lock it) */
1224	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1225	err = ceph_mdsc_do_request(mdsc, dir, req);
1226	if (err) {
1227	d_drop(dentry);
1228	} else if (!req->r_reply_info.head->is_dentry) {
1229	ihold(inode: d_inode(dentry: old_dentry));
1230	d_instantiate(dentry, d_inode(dentry: old_dentry));
1231	}
1232	ceph_mdsc_put_request(req);
1233	return err;
1234	}
1235
1236	static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,
1237	struct ceph_mds_request *req)
1238	{
1239	struct dentry *dentry = req->r_dentry;
1240	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb: dentry->d_sb);
1241	struct ceph_client *cl = fsc->client;
1242	struct ceph_dentry_info *di = ceph_dentry(dentry);
1243	int result = req->r_err ? req->r_err :
1244	le32_to_cpu(req->r_reply_info.head->result);
1245
1246	if (!test_bit(CEPH_DENTRY_ASYNC_UNLINK_BIT, &di->flags))
1247	pr_warn_client(cl,
1248	"dentry %p:%pd async unlink bit is not set\n",
1249	dentry, dentry);
1250
1251	spin_lock(lock: &fsc->async_unlink_conflict_lock);
1252	hash_del_rcu(node: &di->hnode);
1253	spin_unlock(lock: &fsc->async_unlink_conflict_lock);
1254
1255	spin_lock(lock: &dentry->d_lock);
1256	di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1257	wake_up_bit(word: &di->flags, CEPH_DENTRY_ASYNC_UNLINK_BIT);
1258	spin_unlock(lock: &dentry->d_lock);
1259
1260	synchronize_rcu();
1261
1262	if (result == -EJUKEBOX)
1263	goto out;
1264
1265	/* If op failed, mark everyone involved for errors */
1266	if (result) {
1267	int pathlen = 0;
1268	u64 base = 0;
1269	char *path = ceph_mdsc_build_path(mdsc, dentry, plen: &pathlen,
1270	base: &base, for_wire: 0);
1271
1272	/* mark error on parent + clear complete */
1273	mapping_set_error(mapping: req->r_parent->i_mapping, error: result);
1274	ceph_dir_clear_complete(inode: req->r_parent);
1275
1276	/* drop the dentry -- we don't know its status */
1277	if (!d_unhashed(dentry))
1278	d_drop(dentry);
1279
1280	/* mark inode itself for an error (since metadata is bogus) */
1281	mapping_set_error(mapping: req->r_old_inode->i_mapping, error: result);
1282
1283	pr_warn_client(cl, "failure path=(%llx)%s result=%d!\n",
1284	base, IS_ERR(path) ? "<<bad>>" : path, result);
1285	ceph_mdsc_free_path(path, len: pathlen);
1286	}
1287	out:
1288	iput(req->r_old_inode);
1289	ceph_mdsc_release_dir_caps(req);
1290	}
1291
1292	static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry)
1293	{
1294	struct ceph_inode_info *ci = ceph_inode(inode: dir);
1295	struct ceph_dentry_info *di;
1296	int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK;
1297
1298	spin_lock(lock: &ci->i_ceph_lock);
1299	if ((__ceph_caps_issued(ci, NULL) & want) == want) {
1300	ceph_take_cap_refs(ci, caps: want, snap_rwsem_locked: false);
1301	got = want;
1302	}
1303	spin_unlock(lock: &ci->i_ceph_lock);
1304
1305	/* If we didn't get anything, return 0 */
1306	if (!got)
1307	return 0;
1308
1309	spin_lock(lock: &dentry->d_lock);
1310	di = ceph_dentry(dentry);
1311	/*
1312	* - We are holding Fx, which implies Fs caps.
1313	* - Only support async unlink for primary linkage
1314	*/
1315	if (atomic_read(v: &ci->i_shared_gen) != di->lease_shared_gen ||
1316	!(di->flags & CEPH_DENTRY_PRIMARY_LINK))
1317	want = 0;
1318	spin_unlock(lock: &dentry->d_lock);
1319
1320	/* Do we still want what we've got? */
1321	if (want == got)
1322	return got;
1323
1324	ceph_put_cap_refs(ci, had: got);
1325	return 0;
1326	}
1327
1328	/*
1329	* rmdir and unlink are differ only by the metadata op code
1330	*/
1331	static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1332	{
1333	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb: dir->i_sb);
1334	struct ceph_client *cl = fsc->client;
1335	struct ceph_mds_client *mdsc = fsc->mdsc;
1336	struct inode *inode = d_inode(dentry);
1337	struct ceph_mds_request *req;
1338	bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
1339	int err = -EROFS;
1340	int op;
1341
1342	if (ceph_snap(inode: dir) == CEPH_SNAPDIR) {
1343	/* rmdir .snap/foo is RMSNAP */
1344	doutc(cl, "rmsnap %llx.%llx/'%pd' dn\n", ceph_vinop(dir),
1345	dentry);
1346	op = CEPH_MDS_OP_RMSNAP;
1347	} else if (ceph_snap(inode: dir) == CEPH_NOSNAP) {
1348	doutc(cl, "unlink/rmdir %llx.%llx/'%pd' inode %llx.%llx\n",
1349	ceph_vinop(dir), dentry, ceph_vinop(inode));
1350	op = d_is_dir(dentry) ?
1351	CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1352	} else
1353	goto out;
1354	retry:
1355	req = ceph_mdsc_create_request(mdsc, op, mode: USE_AUTH_MDS);
1356	if (IS_ERR(ptr: req)) {
1357	err = PTR_ERR(ptr: req);
1358	goto out;
1359	}
1360	req->r_dentry = dget(dentry);
1361	req->r_num_caps = 2;
1362	req->r_parent = dir;
1363	ihold(inode: dir);
1364	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1365	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1366	req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1367
1368	if (try_async && op == CEPH_MDS_OP_UNLINK &&
1369	(req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) {
1370	struct ceph_dentry_info *di = ceph_dentry(dentry);
1371
1372	doutc(cl, "async unlink on %llx.%llx/'%pd' caps=%s",
1373	ceph_vinop(dir), dentry,
1374	ceph_cap_string(req->r_dir_caps));
1375	set_bit(CEPH_MDS_R_ASYNC, addr: &req->r_req_flags);
1376	req->r_callback = ceph_async_unlink_cb;
1377	req->r_old_inode = d_inode(dentry);
1378	ihold(inode: req->r_old_inode);
1379
1380	spin_lock(lock: &dentry->d_lock);
1381	di->flags |= CEPH_DENTRY_ASYNC_UNLINK;
1382	spin_unlock(lock: &dentry->d_lock);
1383
1384	spin_lock(lock: &fsc->async_unlink_conflict_lock);
1385	hash_add_rcu(fsc->async_unlink_conflict, &di->hnode,
1386	dentry->d_name.hash);
1387	spin_unlock(lock: &fsc->async_unlink_conflict_lock);
1388
1389	err = ceph_mdsc_submit_request(mdsc, dir, req);
1390	if (!err) {
1391	/*
1392	* We have enough caps, so we assume that the unlink
1393	* will succeed. Fix up the target inode and dcache.
1394	*/
1395	drop_nlink(inode);
1396	d_delete(dentry);
1397	} else {
1398	spin_lock(lock: &fsc->async_unlink_conflict_lock);
1399	hash_del_rcu(node: &di->hnode);
1400	spin_unlock(lock: &fsc->async_unlink_conflict_lock);
1401
1402	spin_lock(lock: &dentry->d_lock);
1403	di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1404	spin_unlock(lock: &dentry->d_lock);
1405
1406	if (err == -EJUKEBOX) {
1407	try_async = false;
1408	ceph_mdsc_put_request(req);
1409	goto retry;
1410	}
1411	}
1412	} else {
1413	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
1414	err = ceph_mdsc_do_request(mdsc, dir, req);
1415	if (!err && !req->r_reply_info.head->is_dentry)
1416	d_delete(dentry);
1417	}
1418
1419	ceph_mdsc_put_request(req);
1420	out:
1421	return err;
1422	}
1423
1424	static int ceph_rename(struct mnt_idmap *idmap, struct inode *old_dir,
1425	struct dentry *old_dentry, struct inode *new_dir,
1426	struct dentry *new_dentry, unsigned int flags)
1427	{
1428	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: old_dir->i_sb);
1429	struct ceph_client *cl = mdsc->fsc->client;
1430	struct ceph_mds_request *req;
1431	int op = CEPH_MDS_OP_RENAME;
1432	int err;
1433
1434	if (flags)
1435	return -EINVAL;
1436
1437	if (ceph_snap(inode: old_dir) != ceph_snap(inode: new_dir))
1438	return -EXDEV;
1439	if (ceph_snap(inode: old_dir) != CEPH_NOSNAP) {
1440	if (old_dir == new_dir && ceph_snap(inode: old_dir) == CEPH_SNAPDIR)
1441	op = CEPH_MDS_OP_RENAMESNAP;
1442	else
1443	return -EROFS;
1444	}
1445	/* don't allow cross-quota renames */
1446	if ((old_dir != new_dir) &&
1447	(!ceph_quota_is_same_realm(old: old_dir, new: new_dir)))
1448	return -EXDEV;
1449
1450	err = ceph_wait_on_conflict_unlink(dentry: new_dentry);
1451	if (err)
1452	return err;
1453
1454	err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
1455	flags);
1456	if (err)
1457	return err;
1458
1459	doutc(cl, "%llx.%llx/'%pd' to %llx.%llx/'%pd'\n",
1460	ceph_vinop(old_dir), old_dentry, ceph_vinop(new_dir),
1461	new_dentry);
1462	req = ceph_mdsc_create_request(mdsc, op, mode: USE_AUTH_MDS);
1463	if (IS_ERR(ptr: req))
1464	return PTR_ERR(ptr: req);
1465	ihold(inode: old_dir);
1466	req->r_dentry = dget(dentry: new_dentry);
1467	req->r_num_caps = 2;
1468	req->r_old_dentry = dget(dentry: old_dentry);
1469	req->r_old_dentry_dir = old_dir;
1470	req->r_parent = new_dir;
1471	ihold(inode: new_dir);
1472	set_bit(CEPH_MDS_R_PARENT_LOCKED, addr: &req->r_req_flags);
1473	req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1474	req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1475	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;
1476	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1477	/* release LINK_RDCACHE on source inode (mds will lock it) */
1478	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1479	if (d_really_is_positive(dentry: new_dentry)) {
1480	req->r_inode_drop =
1481	ceph_drop_caps_for_unlink(inode: d_inode(dentry: new_dentry));
1482	}
1483	err = ceph_mdsc_do_request(mdsc, dir: old_dir, req);
1484	if (!err && !req->r_reply_info.head->is_dentry) {
1485	/*
1486	* Normally d_move() is done by fill_trace (called by
1487	* do_request, above). If there is no trace, we need
1488	* to do it here.
1489	*/
1490	d_move(old_dentry, new_dentry);
1491	}
1492	ceph_mdsc_put_request(req);
1493	return err;
1494	}
1495
1496	/*
1497	* Move dentry to tail of mdsc->dentry_leases list when lease is updated.
1498	* Leases at front of the list will expire first. (Assume all leases have
1499	* similar duration)
1500	*
1501	* Called under dentry->d_lock.
1502	*/
1503	void __ceph_dentry_lease_touch(struct ceph_dentry_info *di)
1504	{
1505	struct dentry *dn = di->dentry;
1506	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb: dn->d_sb)->mdsc;
1507	struct ceph_client *cl = mdsc->fsc->client;
1508
1509	doutc(cl, "%p %p '%pd'\n", di, dn, dn);
1510
1511	di->flags |= CEPH_DENTRY_LEASE_LIST;
1512	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1513	di->flags |= CEPH_DENTRY_REFERENCED;
1514	return;
1515	}
1516
1517	spin_lock(lock: &mdsc->dentry_list_lock);
1518	list_move_tail(list: &di->lease_list, head: &mdsc->dentry_leases);
1519	spin_unlock(lock: &mdsc->dentry_list_lock);
1520	}
1521
1522	static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc,
1523	struct ceph_dentry_info *di)
1524	{
1525	di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED);
1526	di->lease_gen = 0;
1527	di->time = jiffies;
1528	list_move_tail(list: &di->lease_list, head: &mdsc->dentry_dir_leases);
1529	}
1530
1531	/*
1532	* When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases
1533	* list if it's not in the list, otherwise set 'referenced' flag.
1534	*
1535	* Called under dentry->d_lock.
1536	*/
1537	void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di)
1538	{
1539	struct dentry *dn = di->dentry;
1540	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb: dn->d_sb)->mdsc;
1541	struct ceph_client *cl = mdsc->fsc->client;
1542
1543	doutc(cl, "%p %p '%pd' (offset 0x%llx)\n", di, dn, dn, di->offset);
1544
1545	if (!list_empty(head: &di->lease_list)) {
1546	if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1547	/* don't remove dentry from dentry lease list
1548	* if its lease is valid */
1549	if (__dentry_lease_is_valid(di))
1550	return;
1551	} else {
1552	di->flags |= CEPH_DENTRY_REFERENCED;
1553	return;
1554	}
1555	}
1556
1557	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1558	di->flags |= CEPH_DENTRY_REFERENCED;
1559	di->flags &= ~CEPH_DENTRY_LEASE_LIST;
1560	return;
1561	}
1562
1563	spin_lock(lock: &mdsc->dentry_list_lock);
1564	__dentry_dir_lease_touch(mdsc, di),
1565	spin_unlock(lock: &mdsc->dentry_list_lock);
1566	}
1567
1568	static void __dentry_lease_unlist(struct ceph_dentry_info *di)
1569	{
1570	struct ceph_mds_client *mdsc;
1571	if (di->flags & CEPH_DENTRY_SHRINK_LIST)
1572	return;
1573	if (list_empty(head: &di->lease_list))
1574	return;
1575
1576	mdsc = ceph_sb_to_fs_client(sb: di->dentry->d_sb)->mdsc;
1577	spin_lock(lock: &mdsc->dentry_list_lock);
1578	list_del_init(entry: &di->lease_list);
1579	spin_unlock(lock: &mdsc->dentry_list_lock);
1580	}
1581
1582	enum {
1583	KEEP = 0,
1584	DELETE = 1,
1585	TOUCH = 2,
1586	STOP = 4,
1587	};
1588
1589	struct ceph_lease_walk_control {
1590	bool dir_lease;
1591	bool expire_dir_lease;
1592	unsigned long nr_to_scan;
1593	unsigned long dir_lease_ttl;
1594	};
1595
1596	static int __dir_lease_check(const struct dentry *, struct ceph_lease_walk_control *);
1597	static int __dentry_lease_check(const struct dentry *);
1598
1599	static unsigned long
1600	__dentry_leases_walk(struct ceph_mds_client *mdsc,
1601	struct ceph_lease_walk_control *lwc)
1602	{
1603	struct ceph_dentry_info *di, *tmp;
1604	struct dentry *dentry, *last = NULL;
1605	struct list_head* list;
1606	LIST_HEAD(dispose);
1607	unsigned long freed = 0;
1608	int ret = 0;
1609
1610	list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases;
1611	spin_lock(lock: &mdsc->dentry_list_lock);
1612	list_for_each_entry_safe(di, tmp, list, lease_list) {
1613	if (!lwc->nr_to_scan)
1614	break;
1615	--lwc->nr_to_scan;
1616
1617	dentry = di->dentry;
1618	if (last == dentry)
1619	break;
1620
1621	if (!spin_trylock(lock: &dentry->d_lock))
1622	continue;
1623
1624	if (__lockref_is_dead(l: &dentry->d_lockref)) {
1625	list_del_init(entry: &di->lease_list);
1626	goto next;
1627	}
1628
1629	if (lwc->dir_lease)
1630	ret = __dir_lease_check(dentry, lwc);
1631	else
1632	ret = __dentry_lease_check(dentry);
1633	if (ret & TOUCH) {
1634	/* move it into tail of dir lease list */
1635	__dentry_dir_lease_touch(mdsc, di);
1636	if (!last)
1637	last = dentry;
1638	}
1639	if (ret & DELETE) {
1640	/* stale lease */
1641	di->flags &= ~CEPH_DENTRY_REFERENCED;
1642	if (dentry->d_lockref.count > 0) {
1643	/* update_dentry_lease() will re-add
1644	* it to lease list, or
1645	* ceph_d_delete() will return 1 when
1646	* last reference is dropped */
1647	list_del_init(entry: &di->lease_list);
1648	} else {
1649	di->flags |= CEPH_DENTRY_SHRINK_LIST;
1650	list_move_tail(list: &di->lease_list, head: &dispose);
1651	dget_dlock(dentry);
1652	}
1653	}
1654	next:
1655	spin_unlock(lock: &dentry->d_lock);
1656	if (ret & STOP)
1657	break;
1658	}
1659	spin_unlock(lock: &mdsc->dentry_list_lock);
1660
1661	while (!list_empty(head: &dispose)) {
1662	di = list_first_entry(&dispose, struct ceph_dentry_info,
1663	lease_list);
1664	dentry = di->dentry;
1665	spin_lock(lock: &dentry->d_lock);
1666
1667	list_del_init(entry: &di->lease_list);
1668	di->flags &= ~CEPH_DENTRY_SHRINK_LIST;
1669	if (di->flags & CEPH_DENTRY_REFERENCED) {
1670	spin_lock(lock: &mdsc->dentry_list_lock);
1671	if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1672	list_add_tail(new: &di->lease_list,
1673	head: &mdsc->dentry_leases);
1674	} else {
1675	__dentry_dir_lease_touch(mdsc, di);
1676	}
1677	spin_unlock(lock: &mdsc->dentry_list_lock);
1678	} else {
1679	freed++;
1680	}
1681
1682	spin_unlock(lock: &dentry->d_lock);
1683	/* ceph_d_delete() does the trick */
1684	dput(dentry);
1685	}
1686	return freed;
1687	}
1688
1689	static int __dentry_lease_check(const struct dentry *dentry)
1690	{
1691	struct ceph_dentry_info *di = ceph_dentry(dentry);
1692	int ret;
1693
1694	if (__dentry_lease_is_valid(di))
1695	return STOP;
1696	ret = __dir_lease_try_check(dentry);
1697	if (ret == -EBUSY)
1698	return KEEP;
1699	if (ret > 0)
1700	return TOUCH;
1701	return DELETE;
1702	}
1703
1704	static int __dir_lease_check(const struct dentry *dentry,
1705	struct ceph_lease_walk_control *lwc)
1706	{
1707	struct ceph_dentry_info *di = ceph_dentry(dentry);
1708
1709	int ret = __dir_lease_try_check(dentry);
1710	if (ret == -EBUSY)
1711	return KEEP;
1712	if (ret > 0) {
1713	if (time_before(jiffies, di->time + lwc->dir_lease_ttl))
1714	return STOP;
1715	/* Move dentry to tail of dir lease list if we don't want
1716	* to delete it. So dentries in the list are checked in a
1717	* round robin manner */
1718	if (!lwc->expire_dir_lease)
1719	return TOUCH;
1720	if (dentry->d_lockref.count > 0 ||
1721	(di->flags & CEPH_DENTRY_REFERENCED))
1722	return TOUCH;
1723	/* invalidate dir lease */
1724	di->lease_shared_gen = 0;
1725	}
1726	return DELETE;
1727	}
1728
1729	int ceph_trim_dentries(struct ceph_mds_client *mdsc)
1730	{
1731	struct ceph_lease_walk_control lwc;
1732	unsigned long count;
1733	unsigned long freed;
1734
1735	spin_lock(lock: &mdsc->caps_list_lock);
1736	if (mdsc->caps_use_max > 0 &&
1737	mdsc->caps_use_count > mdsc->caps_use_max)
1738	count = mdsc->caps_use_count - mdsc->caps_use_max;
1739	else
1740	count = 0;
1741	spin_unlock(lock: &mdsc->caps_list_lock);
1742
1743	lwc.dir_lease = false;
1744	lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE * 2;
1745	freed = __dentry_leases_walk(mdsc, lwc: &lwc);
1746	if (!lwc.nr_to_scan) /* more invalid leases */
1747	return -EAGAIN;
1748
1749	if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE)
1750	lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE;
1751
1752	lwc.dir_lease = true;
1753	lwc.expire_dir_lease = freed < count;
1754	lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ;
1755	freed +=__dentry_leases_walk(mdsc, lwc: &lwc);
1756	if (!lwc.nr_to_scan) /* more to check */
1757	return -EAGAIN;
1758
1759	return freed > 0 ? 1 : 0;
1760	}
1761
1762	/*
1763	* Ensure a dentry lease will no longer revalidate.
1764	*/
1765	void ceph_invalidate_dentry_lease(struct dentry *dentry)
1766	{
1767	struct ceph_dentry_info *di = ceph_dentry(dentry);
1768	spin_lock(lock: &dentry->d_lock);
1769	di->time = jiffies;
1770	di->lease_shared_gen = 0;
1771	di->flags &= ~CEPH_DENTRY_PRIMARY_LINK;
1772	__dentry_lease_unlist(di);
1773	spin_unlock(lock: &dentry->d_lock);
1774	}
1775
1776	/*
1777	* Check if dentry lease is valid. If not, delete the lease. Try to
1778	* renew if the least is more than half up.
1779	*/
1780	static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)
1781	{
1782	struct ceph_mds_session *session;
1783
1784	if (!di->lease_gen)
1785	return false;
1786
1787	session = di->lease_session;
1788	if (session) {
1789	u32 gen;
1790	unsigned long ttl;
1791
1792	gen = atomic_read(v: &session->s_cap_gen);
1793	ttl = session->s_cap_ttl;
1794
1795	if (di->lease_gen == gen &&
1796	time_before(jiffies, ttl) &&
1797	time_before(jiffies, di->time))
1798	return true;
1799	}
1800	di->lease_gen = 0;
1801	return false;
1802	}
1803
1804	static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)
1805	{
1806	struct ceph_dentry_info *di;
1807	struct ceph_mds_session *session = NULL;
1808	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb: dentry->d_sb)->mdsc;
1809	struct ceph_client *cl = mdsc->fsc->client;
1810	u32 seq = 0;
1811	int valid = 0;
1812
1813	spin_lock(lock: &dentry->d_lock);
1814	di = ceph_dentry(dentry);
1815	if (di && __dentry_lease_is_valid(di)) {
1816	valid = 1;
1817
1818	if (di->lease_renew_after &&
1819	time_after(jiffies, di->lease_renew_after)) {
1820	/*
1821	* We should renew. If we're in RCU walk mode
1822	* though, we can't do that so just return
1823	* -ECHILD.
1824	*/
1825	if (flags & LOOKUP_RCU) {
1826	valid = -ECHILD;
1827	} else {
1828	session = ceph_get_mds_session(s: di->lease_session);
1829	seq = di->lease_seq;
1830	di->lease_renew_after = 0;
1831	di->lease_renew_from = jiffies;
1832	}
1833	}
1834	}
1835	spin_unlock(lock: &dentry->d_lock);
1836
1837	if (session) {
1838	ceph_mdsc_lease_send_msg(session, dentry,
1839	CEPH_MDS_LEASE_RENEW, seq);
1840	ceph_put_mds_session(s: session);
1841	}
1842	doutc(cl, "dentry %p = %d\n", dentry, valid);
1843	return valid;
1844	}
1845
1846	/*
1847	* Called under dentry->d_lock.
1848	*/
1849	static int __dir_lease_try_check(const struct dentry *dentry)
1850	{
1851	struct ceph_dentry_info *di = ceph_dentry(dentry);
1852	struct inode *dir;
1853	struct ceph_inode_info *ci;
1854	int valid = 0;
1855
1856	if (!di->lease_shared_gen)
1857	return 0;
1858	if (IS_ROOT(dentry))
1859	return 0;
1860
1861	dir = d_inode(dentry: dentry->d_parent);
1862	ci = ceph_inode(inode: dir);
1863
1864	if (spin_trylock(lock: &ci->i_ceph_lock)) {
1865	if (atomic_read(v: &ci->i_shared_gen) == di->lease_shared_gen &&
1866	__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, t: 0))
1867	valid = 1;
1868	spin_unlock(lock: &ci->i_ceph_lock);
1869	} else {
1870	valid = -EBUSY;
1871	}
1872
1873	if (!valid)
1874	di->lease_shared_gen = 0;
1875	return valid;
1876	}
1877
1878	/*
1879	* Check if directory-wide content lease/cap is valid.
1880	*/
1881	static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry,
1882	struct ceph_mds_client *mdsc)
1883	{
1884	struct ceph_inode_info *ci = ceph_inode(inode: dir);
1885	struct ceph_client *cl = mdsc->fsc->client;
1886	int valid;
1887	int shared_gen;
1888
1889	spin_lock(lock: &ci->i_ceph_lock);
1890	valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, t: 1);
1891	if (valid) {
1892	__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
1893	shared_gen = atomic_read(v: &ci->i_shared_gen);
1894	}
1895	spin_unlock(lock: &ci->i_ceph_lock);
1896	if (valid) {
1897	struct ceph_dentry_info *di;
1898	spin_lock(lock: &dentry->d_lock);
1899	di = ceph_dentry(dentry);
1900	if (dir == d_inode(dentry: dentry->d_parent) &&
1901	di && di->lease_shared_gen == shared_gen)
1902	__ceph_dentry_dir_lease_touch(di);
1903	else
1904	valid = 0;
1905	spin_unlock(lock: &dentry->d_lock);
1906	}
1907	doutc(cl, "dir %p %llx.%llx v%u dentry %p '%pd' = %d\n", dir,
1908	ceph_vinop(dir), (unsigned)atomic_read(&ci->i_shared_gen),
1909	dentry, dentry, valid);
1910	return valid;
1911	}
1912
1913	/*
1914	* Check if cached dentry can be trusted.
1915	*/
1916	static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1917	{
1918	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb: dentry->d_sb)->mdsc;
1919	struct ceph_client *cl = mdsc->fsc->client;
1920	int valid = 0;
1921	struct dentry *parent;
1922	struct inode *dir, *inode;
1923
1924	valid = fscrypt_d_revalidate(dentry, flags);
1925	if (valid <= 0)
1926	return valid;
1927
1928	if (flags & LOOKUP_RCU) {
1929	parent = READ_ONCE(dentry->d_parent);
1930	dir = d_inode_rcu(dentry: parent);
1931	if (!dir)
1932	return -ECHILD;
1933	inode = d_inode_rcu(dentry);
1934	} else {
1935	parent = dget_parent(dentry);
1936	dir = d_inode(dentry: parent);
1937	inode = d_inode(dentry);
1938	}
1939
1940	doutc(cl, "%p '%pd' inode %p offset 0x%llx nokey %d\n",
1941	dentry, dentry, inode, ceph_dentry(dentry)->offset,
1942	!!(dentry->d_flags & DCACHE_NOKEY_NAME));
1943
1944	mdsc = ceph_sb_to_fs_client(sb: dir->i_sb)->mdsc;
1945
1946	/* always trust cached snapped dentries, snapdir dentry */
1947	if (ceph_snap(inode: dir) != CEPH_NOSNAP) {
1948	doutc(cl, "%p '%pd' inode %p is SNAPPED\n", dentry,
1949	dentry, inode);
1950	valid = 1;
1951	} else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1952	valid = 1;
1953	} else {
1954	valid = dentry_lease_is_valid(dentry, flags);
1955	if (valid == -ECHILD)
1956	return valid;
1957	if (valid || dir_lease_is_valid(dir, dentry, mdsc)) {
1958	if (inode)
1959	valid = ceph_is_any_caps(inode);
1960	else
1961	valid = 1;
1962	}
1963	}
1964
1965	if (!valid) {
1966	struct ceph_mds_request *req;
1967	int op, err;
1968	u32 mask;
1969
1970	if (flags & LOOKUP_RCU)
1971	return -ECHILD;
1972
1973	percpu_counter_inc(fbc: &mdsc->metric.d_lease_mis);
1974
1975	op = ceph_snap(inode: dir) == CEPH_SNAPDIR ?
1976	CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
1977	req = ceph_mdsc_create_request(mdsc, op, mode: USE_ANY_MDS);
1978	if (!IS_ERR(ptr: req)) {
1979	req->r_dentry = dget(dentry);
1980	req->r_num_caps = 2;
1981	req->r_parent = dir;
1982	ihold(inode: dir);
1983
1984	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
1985	if (ceph_security_xattr_wanted(in: dir))
1986	mask |= CEPH_CAP_XATTR_SHARED;
1987	req->r_args.getattr.mask = cpu_to_le32(mask);
1988
1989	err = ceph_mdsc_do_request(mdsc, NULL, req);
1990	switch (err) {
1991	case 0:
1992	if (d_really_is_positive(dentry) &&
1993	d_inode(dentry) == req->r_target_inode)
1994	valid = 1;
1995	break;
1996	case -ENOENT:
1997	if (d_really_is_negative(dentry))
1998	valid = 1;
1999	fallthrough;
2000	default:
2001	break;
2002	}
2003	ceph_mdsc_put_request(req);
2004	doutc(cl, "%p '%pd', lookup result=%d\n", dentry,
2005	dentry, err);
2006	}
2007	} else {
2008	percpu_counter_inc(fbc: &mdsc->metric.d_lease_hit);
2009	}
2010
2011	doutc(cl, "%p '%pd' %s\n", dentry, dentry, valid ? "valid" : "invalid");
2012	if (!valid)
2013	ceph_dir_clear_complete(inode: dir);
2014
2015	if (!(flags & LOOKUP_RCU))
2016	dput(parent);
2017	return valid;
2018	}
2019
2020	/*
2021	* Delete unused dentry that doesn't have valid lease
2022	*
2023	* Called under dentry->d_lock.
2024	*/
2025	static int ceph_d_delete(const struct dentry *dentry)
2026	{
2027	struct ceph_dentry_info *di;
2028
2029	/* won't release caps */
2030	if (d_really_is_negative(dentry))
2031	return 0;
2032	if (ceph_snap(inode: d_inode(dentry)) != CEPH_NOSNAP)
2033	return 0;
2034	/* vaild lease? */
2035	di = ceph_dentry(dentry);
2036	if (di) {
2037	if (__dentry_lease_is_valid(di))
2038	return 0;
2039	if (__dir_lease_try_check(dentry))
2040	return 0;
2041	}
2042	return 1;
2043	}
2044
2045	/*
2046	* Release our ceph_dentry_info.
2047	*/
2048	static void ceph_d_release(struct dentry *dentry)
2049	{
2050	struct ceph_dentry_info *di = ceph_dentry(dentry);
2051	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb: dentry->d_sb);
2052
2053	doutc(fsc->client, "dentry %p '%pd'\n", dentry, dentry);
2054
2055	atomic64_dec(v: &fsc->mdsc->metric.total_dentries);
2056
2057	spin_lock(lock: &dentry->d_lock);
2058	__dentry_lease_unlist(di);
2059	dentry->d_fsdata = NULL;
2060	spin_unlock(lock: &dentry->d_lock);
2061
2062	ceph_put_mds_session(s: di->lease_session);
2063	kmem_cache_free(s: ceph_dentry_cachep, objp: di);
2064	}
2065
2066	/*
2067	* When the VFS prunes a dentry from the cache, we need to clear the
2068	* complete flag on the parent directory.
2069	*
2070	* Called under dentry->d_lock.
2071	*/
2072	static void ceph_d_prune(struct dentry *dentry)
2073	{
2074	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(sb: dentry->d_sb);
2075	struct ceph_client *cl = mdsc->fsc->client;
2076	struct ceph_inode_info *dir_ci;
2077	struct ceph_dentry_info *di;
2078
2079	doutc(cl, "dentry %p '%pd'\n", dentry, dentry);
2080
2081	/* do we have a valid parent? */
2082	if (IS_ROOT(dentry))
2083	return;
2084
2085	/* we hold d_lock, so d_parent is stable */
2086	dir_ci = ceph_inode(inode: d_inode(dentry: dentry->d_parent));
2087	if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
2088	return;
2089
2090	/* who calls d_delete() should also disable dcache readdir */
2091	if (d_really_is_negative(dentry))
2092	return;
2093
2094	/* d_fsdata does not get cleared until d_release */
2095	if (!d_unhashed(dentry)) {
2096	__ceph_dir_clear_complete(ci: dir_ci);
2097	return;
2098	}
2099
2100	/* Disable dcache readdir just in case that someone called d_drop()
2101	* or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
2102	* properly (dcache readdir is still enabled) */
2103	di = ceph_dentry(dentry);
2104	if (di->offset > 0 &&
2105	di->lease_shared_gen == atomic_read(v: &dir_ci->i_shared_gen))
2106	__ceph_dir_clear_ordered(ci: dir_ci);
2107	}
2108
2109	/*
2110	* read() on a dir. This weird interface hack only works if mounted
2111	* with '-o dirstat'.
2112	*/
2113	static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
2114	loff_t *ppos)
2115	{
2116	struct ceph_dir_file_info *dfi = file->private_data;
2117	struct inode *inode = file_inode(f: file);
2118	struct ceph_inode_info *ci = ceph_inode(inode);
2119	int left;
2120	const int bufsize = 1024;
2121
2122	if (!ceph_test_mount_opt(ceph_sb_to_fs_client(inode->i_sb), DIRSTAT))
2123	return -EISDIR;
2124
2125	if (!dfi->dir_info) {
2126	dfi->dir_info = kmalloc(size: bufsize, GFP_KERNEL);
2127	if (!dfi->dir_info)
2128	return -ENOMEM;
2129	dfi->dir_info_len =
2130	snprintf(buf: dfi->dir_info, size: bufsize,
2131	fmt: "entries: %20lld\n"
2132	" files: %20lld\n"
2133	" subdirs: %20lld\n"
2134	"rentries: %20lld\n"
2135	" rfiles: %20lld\n"
2136	" rsubdirs: %20lld\n"
2137	"rbytes: %20lld\n"
2138	"rctime: %10lld.%09ld\n",
2139	ci->i_files + ci->i_subdirs,
2140	ci->i_files,
2141	ci->i_subdirs,
2142	ci->i_rfiles + ci->i_rsubdirs,
2143	ci->i_rfiles,
2144	ci->i_rsubdirs,
2145	ci->i_rbytes,
2146	ci->i_rctime.tv_sec,
2147	ci->i_rctime.tv_nsec);
2148	}
2149
2150	if (*ppos >= dfi->dir_info_len)
2151	return 0;
2152	size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
2153	left = copy_to_user(to: buf, from: dfi->dir_info + *ppos, n: size);
2154	if (left == size)
2155	return -EFAULT;
2156	*ppos += (size - left);
2157	return size - left;
2158	}
2159
2160
2161
2162	/*
2163	* Return name hash for a given dentry. This is dependent on
2164	* the parent directory's hash function.
2165	*/
2166	unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
2167	{
2168	struct ceph_inode_info *dci = ceph_inode(inode: dir);
2169	unsigned hash;
2170
2171	switch (dci->i_dir_layout.dl_dir_hash) {
2172	case 0: /* for backward compat */
2173	case CEPH_STR_HASH_LINUX:
2174	return dn->d_name.hash;
2175
2176	default:
2177	spin_lock(lock: &dn->d_lock);
2178	hash = ceph_str_hash(type: dci->i_dir_layout.dl_dir_hash,
2179	s: dn->d_name.name, len: dn->d_name.len);
2180	spin_unlock(lock: &dn->d_lock);
2181	return hash;
2182	}
2183	}
2184
2185	WRAP_DIR_ITER(ceph_readdir) // FIXME!
2186	const struct file_operations ceph_dir_fops = {
2187	.read = ceph_read_dir,
2188	.iterate_shared = shared_ceph_readdir,
2189	.llseek = ceph_dir_llseek,
2190	.open = ceph_open,
2191	.release = ceph_release,
2192	.unlocked_ioctl = ceph_ioctl,
2193	.compat_ioctl = compat_ptr_ioctl,
2194	.fsync = ceph_fsync,
2195	.lock = ceph_lock,
2196	.flock = ceph_flock,
2197	};
2198
2199	const struct file_operations ceph_snapdir_fops = {
2200	.iterate_shared = shared_ceph_readdir,
2201	.llseek = ceph_dir_llseek,
2202	.open = ceph_open,
2203	.release = ceph_release,
2204	};
2205
2206	const struct inode_operations ceph_dir_iops = {
2207	.lookup = ceph_lookup,
2208	.permission = ceph_permission,
2209	.getattr = ceph_getattr,
2210	.setattr = ceph_setattr,
2211	.listxattr = ceph_listxattr,
2212	.get_inode_acl = ceph_get_acl,
2213	.set_acl = ceph_set_acl,
2214	.mknod = ceph_mknod,
2215	.symlink = ceph_symlink,
2216	.mkdir = ceph_mkdir,
2217	.link = ceph_link,
2218	.unlink = ceph_unlink,
2219	.rmdir = ceph_unlink,
2220	.rename = ceph_rename,
2221	.create = ceph_create,
2222	.atomic_open = ceph_atomic_open,
2223	};
2224
2225	const struct inode_operations ceph_snapdir_iops = {
2226	.lookup = ceph_lookup,
2227	.permission = ceph_permission,
2228	.getattr = ceph_getattr,
2229	.mkdir = ceph_mkdir,
2230	.rmdir = ceph_unlink,
2231	.rename = ceph_rename,
2232	};
2233
2234	const struct dentry_operations ceph_dentry_ops = {
2235	.d_revalidate = ceph_d_revalidate,
2236	.d_delete = ceph_d_delete,
2237	.d_release = ceph_d_release,
2238	.d_prune = ceph_d_prune,
2239	.d_init = ceph_d_init,
2240	};
2241