1// SPDX-License-Identifier: GPL-2.0
2#include <linux/ceph/ceph_debug.h>
3
4#include <linux/types.h>
5#include <linux/slab.h>
6
7#include <linux/ceph/cls_lock_client.h>
8#include <linux/ceph/decode.h>
9#include <linux/ceph/libceph.h>
10
11/**
12 * ceph_cls_lock - grab rados lock for object
13 * @osdc: OSD client instance
14 * @oid: object to lock
15 * @oloc: object to lock
16 * @lock_name: the name of the lock
17 * @type: lock type (CEPH_CLS_LOCK_EXCLUSIVE or CEPH_CLS_LOCK_SHARED)
18 * @cookie: user-defined identifier for this instance of the lock
19 * @tag: user-defined tag
20 * @desc: user-defined lock description
21 * @flags: lock flags
22 *
23 * All operations on the same lock should use the same tag.
24 */
25int ceph_cls_lock(struct ceph_osd_client *osdc,
26		  struct ceph_object_id *oid,
27		  struct ceph_object_locator *oloc,
28		  char *lock_name, u8 type, char *cookie,
29		  char *tag, char *desc, u8 flags)
30{
31	int lock_op_buf_size;
32	int name_len = strlen(lock_name);
33	int cookie_len = strlen(cookie);
34	int tag_len = strlen(tag);
35	int desc_len = strlen(desc);
36	void *p, *end;
37	struct page *lock_op_page;
38	struct timespec64 mtime;
39	int ret;
40
41	lock_op_buf_size = name_len + sizeof(__le32) +
42			   cookie_len + sizeof(__le32) +
43			   tag_len + sizeof(__le32) +
44			   desc_len + sizeof(__le32) +
45			   sizeof(struct ceph_timespec) +
46			   /* flag and type */
47			   sizeof(u8) + sizeof(u8) +
48			   CEPH_ENCODING_START_BLK_LEN;
49	if (lock_op_buf_size > PAGE_SIZE)
50		return -E2BIG;
51
52	lock_op_page = alloc_page(GFP_NOIO);
53	if (!lock_op_page)
54		return -ENOMEM;
55
56	p = page_address(lock_op_page);
57	end = p + lock_op_buf_size;
58
59	/* encode cls_lock_lock_op struct */
60	ceph_start_encoding(&p, 1, 1,
61			    lock_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
62	ceph_encode_string(&p, end, lock_name, name_len);
63	ceph_encode_8(&p, type);
64	ceph_encode_string(&p, end, cookie, cookie_len);
65	ceph_encode_string(&p, end, tag, tag_len);
66	ceph_encode_string(&p, end, desc, desc_len);
67	/* only support infinite duration */
68	memset(&mtime, 0, sizeof(mtime));
69	ceph_encode_timespec64(p, &mtime);
70	p += sizeof(struct ceph_timespec);
71	ceph_encode_8(&p, flags);
72
73	dout("%s lock_name %s type %d cookie %s tag %s desc %s flags 0x%x\n",
74	     __func__, lock_name, type, cookie, tag, desc, flags);
75	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "lock",
76			     CEPH_OSD_FLAG_WRITE, lock_op_page,
77			     lock_op_buf_size, NULL, NULL);
78
79	dout("%s: status %d\n", __func__, ret);
80	__free_page(lock_op_page);
81	return ret;
82}
83EXPORT_SYMBOL(ceph_cls_lock);
84
85/**
86 * ceph_cls_unlock - release rados lock for object
87 * @osdc: OSD client instance
88 * @oid: object to lock
89 * @oloc: object to lock
90 * @lock_name: the name of the lock
91 * @cookie: user-defined identifier for this instance of the lock
92 */
93int ceph_cls_unlock(struct ceph_osd_client *osdc,
94		    struct ceph_object_id *oid,
95		    struct ceph_object_locator *oloc,
96		    char *lock_name, char *cookie)
97{
98	int unlock_op_buf_size;
99	int name_len = strlen(lock_name);
100	int cookie_len = strlen(cookie);
101	void *p, *end;
102	struct page *unlock_op_page;
103	int ret;
104
105	unlock_op_buf_size = name_len + sizeof(__le32) +
106			     cookie_len + sizeof(__le32) +
107			     CEPH_ENCODING_START_BLK_LEN;
108	if (unlock_op_buf_size > PAGE_SIZE)
109		return -E2BIG;
110
111	unlock_op_page = alloc_page(GFP_NOIO);
112	if (!unlock_op_page)
113		return -ENOMEM;
114
115	p = page_address(unlock_op_page);
116	end = p + unlock_op_buf_size;
117
118	/* encode cls_lock_unlock_op struct */
119	ceph_start_encoding(&p, 1, 1,
120			    unlock_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
121	ceph_encode_string(&p, end, lock_name, name_len);
122	ceph_encode_string(&p, end, cookie, cookie_len);
123
124	dout("%s lock_name %s cookie %s\n", __func__, lock_name, cookie);
125	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "unlock",
126			     CEPH_OSD_FLAG_WRITE, unlock_op_page,
127			     unlock_op_buf_size, NULL, NULL);
128
129	dout("%s: status %d\n", __func__, ret);
130	__free_page(unlock_op_page);
131	return ret;
132}
133EXPORT_SYMBOL(ceph_cls_unlock);
134
135/**
136 * ceph_cls_break_lock - release rados lock for object for specified client
137 * @osdc: OSD client instance
138 * @oid: object to lock
139 * @oloc: object to lock
140 * @lock_name: the name of the lock
141 * @cookie: user-defined identifier for this instance of the lock
142 * @locker: current lock owner
143 */
144int ceph_cls_break_lock(struct ceph_osd_client *osdc,
145			struct ceph_object_id *oid,
146			struct ceph_object_locator *oloc,
147			char *lock_name, char *cookie,
148			struct ceph_entity_name *locker)
149{
150	int break_op_buf_size;
151	int name_len = strlen(lock_name);
152	int cookie_len = strlen(cookie);
153	struct page *break_op_page;
154	void *p, *end;
155	int ret;
156
157	break_op_buf_size = name_len + sizeof(__le32) +
158			    cookie_len + sizeof(__le32) +
159			    sizeof(u8) + sizeof(__le64) +
160			    CEPH_ENCODING_START_BLK_LEN;
161	if (break_op_buf_size > PAGE_SIZE)
162		return -E2BIG;
163
164	break_op_page = alloc_page(GFP_NOIO);
165	if (!break_op_page)
166		return -ENOMEM;
167
168	p = page_address(break_op_page);
169	end = p + break_op_buf_size;
170
171	/* encode cls_lock_break_op struct */
172	ceph_start_encoding(&p, 1, 1,
173			    break_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
174	ceph_encode_string(&p, end, lock_name, name_len);
175	ceph_encode_copy(&p, locker, sizeof(*locker));
176	ceph_encode_string(&p, end, cookie, cookie_len);
177
178	dout("%s lock_name %s cookie %s locker %s%llu\n", __func__, lock_name,
179	     cookie, ENTITY_NAME(*locker));
180	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "break_lock",
181			     CEPH_OSD_FLAG_WRITE, break_op_page,
182			     break_op_buf_size, NULL, NULL);
183
184	dout("%s: status %d\n", __func__, ret);
185	__free_page(break_op_page);
186	return ret;
187}
188EXPORT_SYMBOL(ceph_cls_break_lock);
189
190int ceph_cls_set_cookie(struct ceph_osd_client *osdc,
191			struct ceph_object_id *oid,
192			struct ceph_object_locator *oloc,
193			char *lock_name, u8 type, char *old_cookie,
194			char *tag, char *new_cookie)
195{
196	int cookie_op_buf_size;
197	int name_len = strlen(lock_name);
198	int old_cookie_len = strlen(old_cookie);
199	int tag_len = strlen(tag);
200	int new_cookie_len = strlen(new_cookie);
201	void *p, *end;
202	struct page *cookie_op_page;
203	int ret;
204
205	cookie_op_buf_size = name_len + sizeof(__le32) +
206			     old_cookie_len + sizeof(__le32) +
207			     tag_len + sizeof(__le32) +
208			     new_cookie_len + sizeof(__le32) +
209			     sizeof(u8) + CEPH_ENCODING_START_BLK_LEN;
210	if (cookie_op_buf_size > PAGE_SIZE)
211		return -E2BIG;
212
213	cookie_op_page = alloc_page(GFP_NOIO);
214	if (!cookie_op_page)
215		return -ENOMEM;
216
217	p = page_address(cookie_op_page);
218	end = p + cookie_op_buf_size;
219
220	/* encode cls_lock_set_cookie_op struct */
221	ceph_start_encoding(&p, 1, 1,
222			    cookie_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
223	ceph_encode_string(&p, end, lock_name, name_len);
224	ceph_encode_8(&p, type);
225	ceph_encode_string(&p, end, old_cookie, old_cookie_len);
226	ceph_encode_string(&p, end, tag, tag_len);
227	ceph_encode_string(&p, end, new_cookie, new_cookie_len);
228
229	dout("%s lock_name %s type %d old_cookie %s tag %s new_cookie %s\n",
230	     __func__, lock_name, type, old_cookie, tag, new_cookie);
231	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "set_cookie",
232			     CEPH_OSD_FLAG_WRITE, cookie_op_page,
233			     cookie_op_buf_size, NULL, NULL);
234
235	dout("%s: status %d\n", __func__, ret);
236	__free_page(cookie_op_page);
237	return ret;
238}
239EXPORT_SYMBOL(ceph_cls_set_cookie);
240
241void ceph_free_lockers(struct ceph_locker *lockers, u32 num_lockers)
242{
243	int i;
244
245	for (i = 0; i < num_lockers; i++)
246		kfree(lockers[i].id.cookie);
247	kfree(lockers);
248}
249EXPORT_SYMBOL(ceph_free_lockers);
250
251static int decode_locker(void **p, void *end, struct ceph_locker *locker)
252{
253	u8 struct_v;
254	u32 len;
255	char *s;
256	int ret;
257
258	ret = ceph_start_decoding(p, end, 1, "locker_id_t", &struct_v, &len);
259	if (ret)
260		return ret;
261
262	ceph_decode_copy(p, &locker->id.name, sizeof(locker->id.name));
263	s = ceph_extract_encoded_string(p, end, NULL, GFP_NOIO);
264	if (IS_ERR(s))
265		return PTR_ERR(s);
266
267	locker->id.cookie = s;
268
269	ret = ceph_start_decoding(p, end, 1, "locker_info_t", &struct_v, &len);
270	if (ret)
271		return ret;
272
273	*p += sizeof(struct ceph_timespec); /* skip expiration */
274
275	ret = ceph_decode_entity_addr(p, end, &locker->info.addr);
276	if (ret)
277		return ret;
278
279	len = ceph_decode_32(p);
280	*p += len; /* skip description */
281
282	dout("%s %s%llu cookie %s addr %s\n", __func__,
283	     ENTITY_NAME(locker->id.name), locker->id.cookie,
284	     ceph_pr_addr(&locker->info.addr));
285	return 0;
286}
287
288static int decode_lockers(void **p, void *end, u8 *type, char **tag,
289			  struct ceph_locker **lockers, u32 *num_lockers)
290{
291	u8 struct_v;
292	u32 struct_len;
293	char *s;
294	int i;
295	int ret;
296
297	ret = ceph_start_decoding(p, end, 1, "cls_lock_get_info_reply",
298				  &struct_v, &struct_len);
299	if (ret)
300		return ret;
301
302	*num_lockers = ceph_decode_32(p);
303	*lockers = kcalloc(*num_lockers, sizeof(**lockers), GFP_NOIO);
304	if (!*lockers)
305		return -ENOMEM;
306
307	for (i = 0; i < *num_lockers; i++) {
308		ret = decode_locker(p, end, *lockers + i);
309		if (ret)
310			goto err_free_lockers;
311	}
312
313	*type = ceph_decode_8(p);
314	s = ceph_extract_encoded_string(p, end, NULL, GFP_NOIO);
315	if (IS_ERR(s)) {
316		ret = PTR_ERR(s);
317		goto err_free_lockers;
318	}
319
320	*tag = s;
321	return 0;
322
323err_free_lockers:
324	ceph_free_lockers(*lockers, *num_lockers);
325	return ret;
326}
327
328/*
329 * On success, the caller is responsible for:
330 *
331 *     kfree(tag);
332 *     ceph_free_lockers(lockers, num_lockers);
333 */
334int ceph_cls_lock_info(struct ceph_osd_client *osdc,
335		       struct ceph_object_id *oid,
336		       struct ceph_object_locator *oloc,
337		       char *lock_name, u8 *type, char **tag,
338		       struct ceph_locker **lockers, u32 *num_lockers)
339{
340	int get_info_op_buf_size;
341	int name_len = strlen(lock_name);
342	struct page *get_info_op_page, *reply_page;
343	size_t reply_len = PAGE_SIZE;
344	void *p, *end;
345	int ret;
346
347	get_info_op_buf_size = name_len + sizeof(__le32) +
348			       CEPH_ENCODING_START_BLK_LEN;
349	if (get_info_op_buf_size > PAGE_SIZE)
350		return -E2BIG;
351
352	get_info_op_page = alloc_page(GFP_NOIO);
353	if (!get_info_op_page)
354		return -ENOMEM;
355
356	reply_page = alloc_page(GFP_NOIO);
357	if (!reply_page) {
358		__free_page(get_info_op_page);
359		return -ENOMEM;
360	}
361
362	p = page_address(get_info_op_page);
363	end = p + get_info_op_buf_size;
364
365	/* encode cls_lock_get_info_op struct */
366	ceph_start_encoding(&p, 1, 1,
367			    get_info_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
368	ceph_encode_string(&p, end, lock_name, name_len);
369
370	dout("%s lock_name %s\n", __func__, lock_name);
371	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "get_info",
372			     CEPH_OSD_FLAG_READ, get_info_op_page,
373			     get_info_op_buf_size, &reply_page, &reply_len);
374
375	dout("%s: status %d\n", __func__, ret);
376	if (ret >= 0) {
377		p = page_address(reply_page);
378		end = p + reply_len;
379
380		ret = decode_lockers(&p, end, type, tag, lockers, num_lockers);
381	}
382
383	__free_page(get_info_op_page);
384	__free_page(reply_page);
385	return ret;
386}
387EXPORT_SYMBOL(ceph_cls_lock_info);
388
389int ceph_cls_assert_locked(struct ceph_osd_request *req, int which,
390			   char *lock_name, u8 type, char *cookie, char *tag)
391{
392	int assert_op_buf_size;
393	int name_len = strlen(lock_name);
394	int cookie_len = strlen(cookie);
395	int tag_len = strlen(tag);
396	struct page **pages;
397	void *p, *end;
398	int ret;
399
400	assert_op_buf_size = name_len + sizeof(__le32) +
401			     cookie_len + sizeof(__le32) +
402			     tag_len + sizeof(__le32) +
403			     sizeof(u8) + CEPH_ENCODING_START_BLK_LEN;
404	if (assert_op_buf_size > PAGE_SIZE)
405		return -E2BIG;
406
407	ret = osd_req_op_cls_init(req, which, "lock", "assert_locked");
408	if (ret)
409		return ret;
410
411	pages = ceph_alloc_page_vector(1, GFP_NOIO);
412	if (IS_ERR(pages))
413		return PTR_ERR(pages);
414
415	p = page_address(pages[0]);
416	end = p + assert_op_buf_size;
417
418	/* encode cls_lock_assert_op struct */
419	ceph_start_encoding(&p, 1, 1,
420			    assert_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
421	ceph_encode_string(&p, end, lock_name, name_len);
422	ceph_encode_8(&p, type);
423	ceph_encode_string(&p, end, cookie, cookie_len);
424	ceph_encode_string(&p, end, tag, tag_len);
425	WARN_ON(p != end);
426
427	osd_req_op_cls_request_data_pages(req, which, pages, assert_op_buf_size,
428					  0, false, true);
429	return 0;
430}
431EXPORT_SYMBOL(ceph_cls_assert_locked);
432