[thirdparty/kernel/linux.git] / net / ceph / cls_lock_client.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/ceph/ceph_debug.h>

#include <linux/types.h>
#include <linux/slab.h>

#include <linux/ceph/cls_lock_client.h>
#include <linux/ceph/decode.h>

/**
 * ceph_cls_lock - grab rados lock for object
 * @oid, @oloc: object to lock
 * @lock_name: the name of the lock
 * @type: lock type (CEPH_CLS_LOCK_EXCLUSIVE or CEPH_CLS_LOCK_SHARED)
 * @cookie: user-defined identifier for this instance of the lock
 * @tag: user-defined tag
 * @desc: user-defined lock description
 * @flags: lock flags
 *
 * All operations on the same lock should use the same tag.
 */
int ceph_cls_lock(struct ceph_osd_client *osdc,
		  struct ceph_object_id *oid,
		  struct ceph_object_locator *oloc,
		  char *lock_name, u8 type, char *cookie,
		  char *tag, char *desc, u8 flags)
{
	int lock_op_buf_size;
	int name_len = strlen(lock_name);
	int cookie_len = strlen(cookie);
	int tag_len = strlen(tag);
	int desc_len = strlen(desc);
	void *p, *end;
	struct page *lock_op_page;
	struct timespec mtime;
	int ret;

	lock_op_buf_size = name_len + sizeof(__le32) +
			   cookie_len + sizeof(__le32) +
			   tag_len + sizeof(__le32) +
			   desc_len + sizeof(__le32) +
			   sizeof(struct ceph_timespec) +
			   /* flag and type */
			   sizeof(u8) + sizeof(u8) +
			   CEPH_ENCODING_START_BLK_LEN;
	if (lock_op_buf_size > PAGE_SIZE)
		return -E2BIG;

	lock_op_page = alloc_page(GFP_NOIO);
	if (!lock_op_page)
		return -ENOMEM;

	p = page_address(lock_op_page);
	end = p + lock_op_buf_size;

	/* encode cls_lock_lock_op struct */
	ceph_start_encoding(&p, 1, 1,
			    lock_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_string(&p, end, lock_name, name_len);
	ceph_encode_8(&p, type);
	ceph_encode_string(&p, end, cookie, cookie_len);
	ceph_encode_string(&p, end, tag, tag_len);
	ceph_encode_string(&p, end, desc, desc_len);
	/* only support infinite duration */
	memset(&mtime, 0, sizeof(mtime));
	ceph_encode_timespec(p, &mtime);
	p += sizeof(struct ceph_timespec);
	ceph_encode_8(&p, flags);

	dout("%s lock_name %s type %d cookie %s tag %s desc %s flags 0x%x\n",
	     __func__, lock_name, type, cookie, tag, desc, flags);
	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "lock",
			     CEPH_OSD_FLAG_WRITE, lock_op_page,
			     lock_op_buf_size, NULL, NULL);

	dout("%s: status %d\n", __func__, ret);
	__free_page(lock_op_page);
	return ret;
}
EXPORT_SYMBOL(ceph_cls_lock);

/**
 * ceph_cls_unlock - release rados lock for object
 * @oid, @oloc: object to lock
 * @lock_name: the name of the lock
 * @cookie: user-defined identifier for this instance of the lock
 */
int ceph_cls_unlock(struct ceph_osd_client *osdc,
		    struct ceph_object_id *oid,
		    struct ceph_object_locator *oloc,
		    char *lock_name, char *cookie)
{
	int unlock_op_buf_size;
	int name_len = strlen(lock_name);
	int cookie_len = strlen(cookie);
	void *p, *end;
	struct page *unlock_op_page;
	int ret;

	unlock_op_buf_size = name_len + sizeof(__le32) +
			     cookie_len + sizeof(__le32) +
			     CEPH_ENCODING_START_BLK_LEN;
	if (unlock_op_buf_size > PAGE_SIZE)
		return -E2BIG;

	unlock_op_page = alloc_page(GFP_NOIO);
	if (!unlock_op_page)
		return -ENOMEM;

	p = page_address(unlock_op_page);
	end = p + unlock_op_buf_size;

	/* encode cls_lock_unlock_op struct */
	ceph_start_encoding(&p, 1, 1,
			    unlock_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_string(&p, end, lock_name, name_len);
	ceph_encode_string(&p, end, cookie, cookie_len);

	dout("%s lock_name %s cookie %s\n", __func__, lock_name, cookie);
	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "unlock",
			     CEPH_OSD_FLAG_WRITE, unlock_op_page,
			     unlock_op_buf_size, NULL, NULL);

	dout("%s: status %d\n", __func__, ret);
	__free_page(unlock_op_page);
	return ret;
}
EXPORT_SYMBOL(ceph_cls_unlock);

/**
 * ceph_cls_break_lock - release rados lock for object for specified client
 * @oid, @oloc: object to lock
 * @lock_name: the name of the lock
 * @cookie: user-defined identifier for this instance of the lock
 * @locker: current lock owner
 */
int ceph_cls_break_lock(struct ceph_osd_client *osdc,
			struct ceph_object_id *oid,
			struct ceph_object_locator *oloc,
			char *lock_name, char *cookie,
			struct ceph_entity_name *locker)
{
	int break_op_buf_size;
	int name_len = strlen(lock_name);
	int cookie_len = strlen(cookie);
	struct page *break_op_page;
	void *p, *end;
	int ret;

	break_op_buf_size = name_len + sizeof(__le32) +
			    cookie_len + sizeof(__le32) +
			    sizeof(u8) + sizeof(__le64) +
			    CEPH_ENCODING_START_BLK_LEN;
	if (break_op_buf_size > PAGE_SIZE)
		return -E2BIG;

	break_op_page = alloc_page(GFP_NOIO);
	if (!break_op_page)
		return -ENOMEM;

	p = page_address(break_op_page);
	end = p + break_op_buf_size;

	/* encode cls_lock_break_op struct */
	ceph_start_encoding(&p, 1, 1,
			    break_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_string(&p, end, lock_name, name_len);
	ceph_encode_copy(&p, locker, sizeof(*locker));
	ceph_encode_string(&p, end, cookie, cookie_len);

	dout("%s lock_name %s cookie %s locker %s%llu\n", __func__, lock_name,
	     cookie, ENTITY_NAME(*locker));
	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "break_lock",
			     CEPH_OSD_FLAG_WRITE, break_op_page,
			     break_op_buf_size, NULL, NULL);

	dout("%s: status %d\n", __func__, ret);
	__free_page(break_op_page);
	return ret;
}
EXPORT_SYMBOL(ceph_cls_break_lock);

int ceph_cls_set_cookie(struct ceph_osd_client *osdc,
			struct ceph_object_id *oid,
			struct ceph_object_locator *oloc,
			char *lock_name, u8 type, char *old_cookie,
			char *tag, char *new_cookie)
{
	int cookie_op_buf_size;
	int name_len = strlen(lock_name);
	int old_cookie_len = strlen(old_cookie);
	int tag_len = strlen(tag);
	int new_cookie_len = strlen(new_cookie);
	void *p, *end;
	struct page *cookie_op_page;
	int ret;

	cookie_op_buf_size = name_len + sizeof(__le32) +
			     old_cookie_len + sizeof(__le32) +
			     tag_len + sizeof(__le32) +
			     new_cookie_len + sizeof(__le32) +
			     sizeof(u8) + CEPH_ENCODING_START_BLK_LEN;
	if (cookie_op_buf_size > PAGE_SIZE)
		return -E2BIG;

	cookie_op_page = alloc_page(GFP_NOIO);
	if (!cookie_op_page)
		return -ENOMEM;

	p = page_address(cookie_op_page);
	end = p + cookie_op_buf_size;

	/* encode cls_lock_set_cookie_op struct */
	ceph_start_encoding(&p, 1, 1,
			    cookie_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_string(&p, end, lock_name, name_len);
	ceph_encode_8(&p, type);
	ceph_encode_string(&p, end, old_cookie, old_cookie_len);
	ceph_encode_string(&p, end, tag, tag_len);
	ceph_encode_string(&p, end, new_cookie, new_cookie_len);

	dout("%s lock_name %s type %d old_cookie %s tag %s new_cookie %s\n",
	     __func__, lock_name, type, old_cookie, tag, new_cookie);
	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "set_cookie",
			     CEPH_OSD_FLAG_WRITE, cookie_op_page,
			     cookie_op_buf_size, NULL, NULL);

	dout("%s: status %d\n", __func__, ret);
	__free_page(cookie_op_page);
	return ret;
}
EXPORT_SYMBOL(ceph_cls_set_cookie);

void ceph_free_lockers(struct ceph_locker *lockers, u32 num_lockers)
{
	int i;

	for (i = 0; i < num_lockers; i++)
		kfree(lockers[i].id.cookie);
	kfree(lockers);
}
EXPORT_SYMBOL(ceph_free_lockers);

static int decode_locker(void **p, void *end, struct ceph_locker *locker)
{
	u8 struct_v;
	u32 len;
	char *s;
	int ret;

	ret = ceph_start_decoding(p, end, 1, "locker_id_t", &struct_v, &len);
	if (ret)
		return ret;

	ceph_decode_copy(p, &locker->id.name, sizeof(locker->id.name));
	s = ceph_extract_encoded_string(p, end, NULL, GFP_NOIO);
	if (IS_ERR(s))
		return PTR_ERR(s);

	locker->id.cookie = s;

	ret = ceph_start_decoding(p, end, 1, "locker_info_t", &struct_v, &len);
	if (ret)
		return ret;

	*p += sizeof(struct ceph_timespec); /* skip expiration */
	ceph_decode_copy(p, &locker->info.addr, sizeof(locker->info.addr));
	ceph_decode_addr(&locker->info.addr);
	len = ceph_decode_32(p);
	*p += len; /* skip description */

	dout("%s %s%llu cookie %s addr %s\n", __func__,
	     ENTITY_NAME(locker->id.name), locker->id.cookie,
	     ceph_pr_addr(&locker->info.addr.in_addr));
	return 0;
}

static int decode_lockers(void **p, void *end, u8 *type, char **tag,
			  struct ceph_locker **lockers, u32 *num_lockers)
{
	u8 struct_v;
	u32 struct_len;
	char *s;
	int i;
	int ret;

	ret = ceph_start_decoding(p, end, 1, "cls_lock_get_info_reply",
				  &struct_v, &struct_len);
	if (ret)
		return ret;

	*num_lockers = ceph_decode_32(p);
	*lockers = kcalloc(*num_lockers, sizeof(**lockers), GFP_NOIO);
	if (!*lockers)
		return -ENOMEM;

	for (i = 0; i < *num_lockers; i++) {
		ret = decode_locker(p, end, *lockers + i);
		if (ret)
			goto err_free_lockers;
	}

	*type = ceph_decode_8(p);
	s = ceph_extract_encoded_string(p, end, NULL, GFP_NOIO);
	if (IS_ERR(s)) {
		ret = PTR_ERR(s);
		goto err_free_lockers;
	}

	*tag = s;
	return 0;

err_free_lockers:
	ceph_free_lockers(*lockers, *num_lockers);
	return ret;
}

/*
 * On success, the caller is responsible for:
 *
 *     kfree(tag);
 *     ceph_free_lockers(lockers, num_lockers);
 */
int ceph_cls_lock_info(struct ceph_osd_client *osdc,
		       struct ceph_object_id *oid,
		       struct ceph_object_locator *oloc,
		       char *lock_name, u8 *type, char **tag,
		       struct ceph_locker **lockers, u32 *num_lockers)
{
	int get_info_op_buf_size;
	int name_len = strlen(lock_name);
	struct page *get_info_op_page, *reply_page;
	size_t reply_len = PAGE_SIZE;
	void *p, *end;
	int ret;

	get_info_op_buf_size = name_len + sizeof(__le32) +
			       CEPH_ENCODING_START_BLK_LEN;
	if (get_info_op_buf_size > PAGE_SIZE)
		return -E2BIG;

	get_info_op_page = alloc_page(GFP_NOIO);
	if (!get_info_op_page)
		return -ENOMEM;

	reply_page = alloc_page(GFP_NOIO);
	if (!reply_page) {
		__free_page(get_info_op_page);
		return -ENOMEM;
	}

	p = page_address(get_info_op_page);
	end = p + get_info_op_buf_size;

	/* encode cls_lock_get_info_op struct */
	ceph_start_encoding(&p, 1, 1,
			    get_info_op_buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_string(&p, end, lock_name, name_len);

	dout("%s lock_name %s\n", __func__, lock_name);
	ret = ceph_osdc_call(osdc, oid, oloc, "lock", "get_info",
			     CEPH_OSD_FLAG_READ, get_info_op_page,
			     get_info_op_buf_size, reply_page, &reply_len);

	dout("%s: status %d\n", __func__, ret);
	if (ret >= 0) {
		p = page_address(reply_page);
		end = p + reply_len;

		ret = decode_lockers(&p, end, type, tag, lockers, num_lockers);
	}

	__free_page(get_info_op_page);
	__free_page(reply_page);
	return ret;
}
EXPORT_SYMBOL(ceph_cls_lock_info);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
f66241cb DF	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 timespec 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_timespec(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",
54ea0046 ID	73	CEPH_OSD_FLAG_WRITE, lock_op_page,
54ea0046 ID	74	lock_op_buf_size, NULL, NULL);
f66241cb DF	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",
54ea0046 ID	121	CEPH_OSD_FLAG_WRITE, unlock_op_page,
54ea0046 ID	122	unlock_op_buf_size, NULL, NULL);
f66241cb DF	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",
54ea0046 ID	174	CEPH_OSD_FLAG_WRITE, break_op_page,
54ea0046 ID	175	break_op_buf_size, NULL, NULL);
f66241cb DF	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);
d4ed4a53	182
14bb211d ID	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
d4ed4a53 DF	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;
2544a020	333	size_t reply_len = PAGE_SIZE;
d4ed4a53 DF	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);