xref: /linux/net/ceph/cls_lock_client.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
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 
10 /**
11  * ceph_cls_lock - grab rados lock for object
12  * @oid, @oloc: object to lock
13  * @lock_name: the name of the lock
14  * @type: lock type (CEPH_CLS_LOCK_EXCLUSIVE or CEPH_CLS_LOCK_SHARED)
15  * @cookie: user-defined identifier for this instance of the lock
16  * @tag: user-defined tag
17  * @desc: user-defined lock description
18  * @flags: lock flags
19  *
20  * All operations on the same lock should use the same tag.
21  */
22 int ceph_cls_lock(struct ceph_osd_client *osdc,
23 		  struct ceph_object_id *oid,
24 		  struct ceph_object_locator *oloc,
25 		  char *lock_name, u8 type, char *cookie,
26 		  char *tag, char *desc, u8 flags)
27 {
28 	int lock_op_buf_size;
29 	int name_len = strlen(lock_name);
30 	int cookie_len = strlen(cookie);
31 	int tag_len = strlen(tag);
32 	int desc_len = strlen(desc);
33 	void *p, *end;
34 	struct page *lock_op_page;
35 	struct timespec64 mtime;
36 	int ret;
37 
38 	lock_op_buf_size = name_len + sizeof(__le32) +
39 			   cookie_len + sizeof(__le32) +
40 			   tag_len + sizeof(__le32) +
41 			   desc_len + sizeof(__le32) +
42 			   sizeof(struct ceph_timespec) +
43 			   /* flag and type */
44 			   sizeof(u8) + sizeof(u8) +
45 			   CEPH_ENCODING_START_BLK_LEN;
46 	if (lock_op_buf_size > PAGE_SIZE)
47 		return -E2BIG;
48 
49 	lock_op_page = alloc_page(GFP_NOIO);
50 	if (!lock_op_page)
51 		return -ENOMEM;
52 
53 	p = page_address(lock_op_page);
54 	end = p + lock_op_buf_size;
55 
56 	/* encode cls_lock_lock_op struct */
57 	ceph_start_encoding(&p, 1, 1,
58 			    lock_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
59 	ceph_encode_string(&p, end, lock_name, name_len);
60 	ceph_encode_8(&p, type);
61 	ceph_encode_string(&p, end, cookie, cookie_len);
62 	ceph_encode_string(&p, end, tag, tag_len);
63 	ceph_encode_string(&p, end, desc, desc_len);
64 	/* only support infinite duration */
65 	memset(&mtime, 0, sizeof(mtime));
66 	ceph_encode_timespec64(p, &mtime);
67 	p += sizeof(struct ceph_timespec);
68 	ceph_encode_8(&p, flags);
69 
70 	dout("%s lock_name %s type %d cookie %s tag %s desc %s flags 0x%x\n",
71 	     __func__, lock_name, type, cookie, tag, desc, flags);
72 	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "lock",
73 			     CEPH_OSD_FLAG_WRITE, lock_op_page,
74 			     lock_op_buf_size, NULL, NULL);
75 
76 	dout("%s: status %d\n", __func__, ret);
77 	__free_page(lock_op_page);
78 	return ret;
79 }
80 EXPORT_SYMBOL(ceph_cls_lock);
81 
82 /**
83  * ceph_cls_unlock - release rados lock for object
84  * @oid, @oloc: object to lock
85  * @lock_name: the name of the lock
86  * @cookie: user-defined identifier for this instance of the lock
87  */
88 int ceph_cls_unlock(struct ceph_osd_client *osdc,
89 		    struct ceph_object_id *oid,
90 		    struct ceph_object_locator *oloc,
91 		    char *lock_name, char *cookie)
92 {
93 	int unlock_op_buf_size;
94 	int name_len = strlen(lock_name);
95 	int cookie_len = strlen(cookie);
96 	void *p, *end;
97 	struct page *unlock_op_page;
98 	int ret;
99 
100 	unlock_op_buf_size = name_len + sizeof(__le32) +
101 			     cookie_len + sizeof(__le32) +
102 			     CEPH_ENCODING_START_BLK_LEN;
103 	if (unlock_op_buf_size > PAGE_SIZE)
104 		return -E2BIG;
105 
106 	unlock_op_page = alloc_page(GFP_NOIO);
107 	if (!unlock_op_page)
108 		return -ENOMEM;
109 
110 	p = page_address(unlock_op_page);
111 	end = p + unlock_op_buf_size;
112 
113 	/* encode cls_lock_unlock_op struct */
114 	ceph_start_encoding(&p, 1, 1,
115 			    unlock_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
116 	ceph_encode_string(&p, end, lock_name, name_len);
117 	ceph_encode_string(&p, end, cookie, cookie_len);
118 
119 	dout("%s lock_name %s cookie %s\n", __func__, lock_name, cookie);
120 	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "unlock",
121 			     CEPH_OSD_FLAG_WRITE, unlock_op_page,
122 			     unlock_op_buf_size, NULL, NULL);
123 
124 	dout("%s: status %d\n", __func__, ret);
125 	__free_page(unlock_op_page);
126 	return ret;
127 }
128 EXPORT_SYMBOL(ceph_cls_unlock);
129 
130 /**
131  * ceph_cls_break_lock - release rados lock for object for specified client
132  * @oid, @oloc: object to lock
133  * @lock_name: the name of the lock
134  * @cookie: user-defined identifier for this instance of the lock
135  * @locker: current lock owner
136  */
137 int ceph_cls_break_lock(struct ceph_osd_client *osdc,
138 			struct ceph_object_id *oid,
139 			struct ceph_object_locator *oloc,
140 			char *lock_name, char *cookie,
141 			struct ceph_entity_name *locker)
142 {
143 	int break_op_buf_size;
144 	int name_len = strlen(lock_name);
145 	int cookie_len = strlen(cookie);
146 	struct page *break_op_page;
147 	void *p, *end;
148 	int ret;
149 
150 	break_op_buf_size = name_len + sizeof(__le32) +
151 			    cookie_len + sizeof(__le32) +
152 			    sizeof(u8) + sizeof(__le64) +
153 			    CEPH_ENCODING_START_BLK_LEN;
154 	if (break_op_buf_size > PAGE_SIZE)
155 		return -E2BIG;
156 
157 	break_op_page = alloc_page(GFP_NOIO);
158 	if (!break_op_page)
159 		return -ENOMEM;
160 
161 	p = page_address(break_op_page);
162 	end = p + break_op_buf_size;
163 
164 	/* encode cls_lock_break_op struct */
165 	ceph_start_encoding(&p, 1, 1,
166 			    break_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
167 	ceph_encode_string(&p, end, lock_name, name_len);
168 	ceph_encode_copy(&p, locker, sizeof(*locker));
169 	ceph_encode_string(&p, end, cookie, cookie_len);
170 
171 	dout("%s lock_name %s cookie %s locker %s%llu\n", __func__, lock_name,
172 	     cookie, ENTITY_NAME(*locker));
173 	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "break_lock",
174 			     CEPH_OSD_FLAG_WRITE, break_op_page,
175 			     break_op_buf_size, NULL, NULL);
176 
177 	dout("%s: status %d\n", __func__, ret);
178 	__free_page(break_op_page);
179 	return ret;
180 }
181 EXPORT_SYMBOL(ceph_cls_break_lock);
182 
183 int ceph_cls_set_cookie(struct ceph_osd_client *osdc,
184 			struct ceph_object_id *oid,
185 			struct ceph_object_locator *oloc,
186 			char *lock_name, u8 type, char *old_cookie,
187 			char *tag, char *new_cookie)
188 {
189 	int cookie_op_buf_size;
190 	int name_len = strlen(lock_name);
191 	int old_cookie_len = strlen(old_cookie);
192 	int tag_len = strlen(tag);
193 	int new_cookie_len = strlen(new_cookie);
194 	void *p, *end;
195 	struct page *cookie_op_page;
196 	int ret;
197 
198 	cookie_op_buf_size = name_len + sizeof(__le32) +
199 			     old_cookie_len + sizeof(__le32) +
200 			     tag_len + sizeof(__le32) +
201 			     new_cookie_len + sizeof(__le32) +
202 			     sizeof(u8) + CEPH_ENCODING_START_BLK_LEN;
203 	if (cookie_op_buf_size > PAGE_SIZE)
204 		return -E2BIG;
205 
206 	cookie_op_page = alloc_page(GFP_NOIO);
207 	if (!cookie_op_page)
208 		return -ENOMEM;
209 
210 	p = page_address(cookie_op_page);
211 	end = p + cookie_op_buf_size;
212 
213 	/* encode cls_lock_set_cookie_op struct */
214 	ceph_start_encoding(&p, 1, 1,
215 			    cookie_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
216 	ceph_encode_string(&p, end, lock_name, name_len);
217 	ceph_encode_8(&p, type);
218 	ceph_encode_string(&p, end, old_cookie, old_cookie_len);
219 	ceph_encode_string(&p, end, tag, tag_len);
220 	ceph_encode_string(&p, end, new_cookie, new_cookie_len);
221 
222 	dout("%s lock_name %s type %d old_cookie %s tag %s new_cookie %s\n",
223 	     __func__, lock_name, type, old_cookie, tag, new_cookie);
224 	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "set_cookie",
225 			     CEPH_OSD_FLAG_WRITE, cookie_op_page,
226 			     cookie_op_buf_size, NULL, NULL);
227 
228 	dout("%s: status %d\n", __func__, ret);
229 	__free_page(cookie_op_page);
230 	return ret;
231 }
232 EXPORT_SYMBOL(ceph_cls_set_cookie);
233 
234 void ceph_free_lockers(struct ceph_locker *lockers, u32 num_lockers)
235 {
236 	int i;
237 
238 	for (i = 0; i < num_lockers; i++)
239 		kfree(lockers[i].id.cookie);
240 	kfree(lockers);
241 }
242 EXPORT_SYMBOL(ceph_free_lockers);
243 
244 static int decode_locker(void **p, void *end, struct ceph_locker *locker)
245 {
246 	u8 struct_v;
247 	u32 len;
248 	char *s;
249 	int ret;
250 
251 	ret = ceph_start_decoding(p, end, 1, "locker_id_t", &struct_v, &len);
252 	if (ret)
253 		return ret;
254 
255 	ceph_decode_copy(p, &locker->id.name, sizeof(locker->id.name));
256 	s = ceph_extract_encoded_string(p, end, NULL, GFP_NOIO);
257 	if (IS_ERR(s))
258 		return PTR_ERR(s);
259 
260 	locker->id.cookie = s;
261 
262 	ret = ceph_start_decoding(p, end, 1, "locker_info_t", &struct_v, &len);
263 	if (ret)
264 		return ret;
265 
266 	*p += sizeof(struct ceph_timespec); /* skip expiration */
267 	ceph_decode_copy(p, &locker->info.addr, sizeof(locker->info.addr));
268 	ceph_decode_addr(&locker->info.addr);
269 	len = ceph_decode_32(p);
270 	*p += len; /* skip description */
271 
272 	dout("%s %s%llu cookie %s addr %s\n", __func__,
273 	     ENTITY_NAME(locker->id.name), locker->id.cookie,
274 	     ceph_pr_addr(&locker->info.addr.in_addr));
275 	return 0;
276 }
277 
278 static int decode_lockers(void **p, void *end, u8 *type, char **tag,
279 			  struct ceph_locker **lockers, u32 *num_lockers)
280 {
281 	u8 struct_v;
282 	u32 struct_len;
283 	char *s;
284 	int i;
285 	int ret;
286 
287 	ret = ceph_start_decoding(p, end, 1, "cls_lock_get_info_reply",
288 				  &struct_v, &struct_len);
289 	if (ret)
290 		return ret;
291 
292 	*num_lockers = ceph_decode_32(p);
293 	*lockers = kcalloc(*num_lockers, sizeof(**lockers), GFP_NOIO);
294 	if (!*lockers)
295 		return -ENOMEM;
296 
297 	for (i = 0; i < *num_lockers; i++) {
298 		ret = decode_locker(p, end, *lockers + i);
299 		if (ret)
300 			goto err_free_lockers;
301 	}
302 
303 	*type = ceph_decode_8(p);
304 	s = ceph_extract_encoded_string(p, end, NULL, GFP_NOIO);
305 	if (IS_ERR(s)) {
306 		ret = PTR_ERR(s);
307 		goto err_free_lockers;
308 	}
309 
310 	*tag = s;
311 	return 0;
312 
313 err_free_lockers:
314 	ceph_free_lockers(*lockers, *num_lockers);
315 	return ret;
316 }
317 
318 /*
319  * On success, the caller is responsible for:
320  *
321  *     kfree(tag);
322  *     ceph_free_lockers(lockers, num_lockers);
323  */
324 int ceph_cls_lock_info(struct ceph_osd_client *osdc,
325 		       struct ceph_object_id *oid,
326 		       struct ceph_object_locator *oloc,
327 		       char *lock_name, u8 *type, char **tag,
328 		       struct ceph_locker **lockers, u32 *num_lockers)
329 {
330 	int get_info_op_buf_size;
331 	int name_len = strlen(lock_name);
332 	struct page *get_info_op_page, *reply_page;
333 	size_t reply_len = PAGE_SIZE;
334 	void *p, *end;
335 	int ret;
336 
337 	get_info_op_buf_size = name_len + sizeof(__le32) +
338 			       CEPH_ENCODING_START_BLK_LEN;
339 	if (get_info_op_buf_size > PAGE_SIZE)
340 		return -E2BIG;
341 
342 	get_info_op_page = alloc_page(GFP_NOIO);
343 	if (!get_info_op_page)
344 		return -ENOMEM;
345 
346 	reply_page = alloc_page(GFP_NOIO);
347 	if (!reply_page) {
348 		__free_page(get_info_op_page);
349 		return -ENOMEM;
350 	}
351 
352 	p = page_address(get_info_op_page);
353 	end = p + get_info_op_buf_size;
354 
355 	/* encode cls_lock_get_info_op struct */
356 	ceph_start_encoding(&p, 1, 1,
357 			    get_info_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
358 	ceph_encode_string(&p, end, lock_name, name_len);
359 
360 	dout("%s lock_name %s\n", __func__, lock_name);
361 	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "get_info",
362 			     CEPH_OSD_FLAG_READ, get_info_op_page,
363 			     get_info_op_buf_size, reply_page, &reply_len);
364 
365 	dout("%s: status %d\n", __func__, ret);
366 	if (ret >= 0) {
367 		p = page_address(reply_page);
368 		end = p + reply_len;
369 
370 		ret = decode_lockers(&p, end, type, tag, lockers, num_lockers);
371 	}
372 
373 	__free_page(get_info_op_page);
374 	__free_page(reply_page);
375 	return ret;
376 }
377 EXPORT_SYMBOL(ceph_cls_lock_info);
378