1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19  *
20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21  * CA 95054 USA or visit www.sun.com if you need additional information or
22  * have any questions.
23  *
24  * GPL HEADER END
25  */
26 /*
27  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2012, Intel Corporation.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  *
36  * lustre/ptlrpc/llog_client.c
37  *
38  * remote api for llog - client side
39  *
40  * Author: Andreas Dilger <adilger@clusterfs.com>
41  */
42 
43 #define DEBUG_SUBSYSTEM S_LOG
44 
45 #include "../../include/linux/libcfs/libcfs.h"
46 
47 #include "../include/obd_class.h"
48 #include "../include/lustre_log.h"
49 #include "../include/lustre_net.h"
50 #include <linux/list.h>
51 
52 #define LLOG_CLIENT_ENTRY(ctxt, imp) do {				\
53 	mutex_lock(&ctxt->loc_mutex);					\
54 	if (ctxt->loc_imp) {						\
55 		imp = class_import_get(ctxt->loc_imp);			\
56 	} else {							\
57 		CERROR("ctxt->loc_imp == NULL for context idx %d."	\
58 		       "Unable to complete MDS/OSS recovery,"		\
59 		       "but I'll try again next time.  Not fatal.\n",	\
60 		       ctxt->loc_idx);					\
61 		imp = NULL;						\
62 		mutex_unlock(&ctxt->loc_mutex);				\
63 		return (-EINVAL);					\
64 	}								\
65 	mutex_unlock(&ctxt->loc_mutex);					\
66 } while (0)
67 
68 #define LLOG_CLIENT_EXIT(ctxt, imp) do {				\
69 	mutex_lock(&ctxt->loc_mutex);					\
70 	if (ctxt->loc_imp != imp)					\
71 		CWARN("loc_imp has changed from %p to %p\n",		\
72 		       ctxt->loc_imp, imp);				\
73 	class_import_put(imp);						\
74 	mutex_unlock(&ctxt->loc_mutex);					\
75 } while (0)
76 
77 /* This is a callback from the llog_* functions.
78  * Assumes caller has already pushed us into the kernel context. */
llog_client_open(const struct lu_env * env,struct llog_handle * lgh,struct llog_logid * logid,char * name,enum llog_open_param open_param)79 static int llog_client_open(const struct lu_env *env,
80 			    struct llog_handle *lgh, struct llog_logid *logid,
81 			    char *name, enum llog_open_param open_param)
82 {
83 	struct obd_import *imp;
84 	struct llogd_body *body;
85 	struct llog_ctxt *ctxt = lgh->lgh_ctxt;
86 	struct ptlrpc_request *req = NULL;
87 	int rc;
88 
89 	LLOG_CLIENT_ENTRY(ctxt, imp);
90 
91 	/* client cannot create llog */
92 	LASSERTF(open_param != LLOG_OPEN_NEW, "%#x\n", open_param);
93 	LASSERT(lgh);
94 
95 	req = ptlrpc_request_alloc(imp, &RQF_LLOG_ORIGIN_HANDLE_CREATE);
96 	if (req == NULL) {
97 		rc = -ENOMEM;
98 		goto out;
99 	}
100 
101 	if (name)
102 		req_capsule_set_size(&req->rq_pill, &RMF_NAME, RCL_CLIENT,
103 				     strlen(name) + 1);
104 
105 	rc = ptlrpc_request_pack(req, LUSTRE_LOG_VERSION,
106 				 LLOG_ORIGIN_HANDLE_CREATE);
107 	if (rc) {
108 		ptlrpc_request_free(req);
109 		req = NULL;
110 		goto out;
111 	}
112 	ptlrpc_request_set_replen(req);
113 
114 	body = req_capsule_client_get(&req->rq_pill, &RMF_LLOGD_BODY);
115 	if (logid)
116 		body->lgd_logid = *logid;
117 	body->lgd_ctxt_idx = ctxt->loc_idx - 1;
118 
119 	if (name) {
120 		char *tmp;
121 
122 		tmp = req_capsule_client_sized_get(&req->rq_pill, &RMF_NAME,
123 						   strlen(name) + 1);
124 		LASSERT(tmp);
125 		strcpy(tmp, name);
126 	}
127 
128 	rc = ptlrpc_queue_wait(req);
129 	if (rc)
130 		goto out;
131 
132 	body = req_capsule_server_get(&req->rq_pill, &RMF_LLOGD_BODY);
133 	if (body == NULL) {
134 		rc = -EFAULT;
135 		goto out;
136 	}
137 
138 	lgh->lgh_id = body->lgd_logid;
139 	lgh->lgh_ctxt = ctxt;
140 out:
141 	LLOG_CLIENT_EXIT(ctxt, imp);
142 	ptlrpc_req_finished(req);
143 	return rc;
144 }
145 
llog_client_next_block(const struct lu_env * env,struct llog_handle * loghandle,int * cur_idx,int next_idx,__u64 * cur_offset,void * buf,int len)146 static int llog_client_next_block(const struct lu_env *env,
147 				  struct llog_handle *loghandle,
148 				  int *cur_idx, int next_idx,
149 				  __u64 *cur_offset, void *buf, int len)
150 {
151 	struct obd_import *imp;
152 	struct ptlrpc_request *req = NULL;
153 	struct llogd_body *body;
154 	void *ptr;
155 	int rc;
156 
157 	LLOG_CLIENT_ENTRY(loghandle->lgh_ctxt, imp);
158 	req = ptlrpc_request_alloc_pack(imp, &RQF_LLOG_ORIGIN_HANDLE_NEXT_BLOCK,
159 					LUSTRE_LOG_VERSION,
160 					LLOG_ORIGIN_HANDLE_NEXT_BLOCK);
161 	if (req == NULL) {
162 		rc = -ENOMEM;
163 		goto err_exit;
164 	}
165 
166 	body = req_capsule_client_get(&req->rq_pill, &RMF_LLOGD_BODY);
167 	body->lgd_logid = loghandle->lgh_id;
168 	body->lgd_ctxt_idx = loghandle->lgh_ctxt->loc_idx - 1;
169 	body->lgd_llh_flags = loghandle->lgh_hdr->llh_flags;
170 	body->lgd_index = next_idx;
171 	body->lgd_saved_index = *cur_idx;
172 	body->lgd_len = len;
173 	body->lgd_cur_offset = *cur_offset;
174 
175 	req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_SERVER, len);
176 	ptlrpc_request_set_replen(req);
177 	rc = ptlrpc_queue_wait(req);
178 	if (rc)
179 		goto out;
180 
181 	body = req_capsule_server_get(&req->rq_pill, &RMF_LLOGD_BODY);
182 	if (body == NULL) {
183 		rc = -EFAULT;
184 		goto out;
185 	}
186 
187 	/* The log records are swabbed as they are processed */
188 	ptr = req_capsule_server_get(&req->rq_pill, &RMF_EADATA);
189 	if (ptr == NULL) {
190 		rc = -EFAULT;
191 		goto out;
192 	}
193 
194 	*cur_idx = body->lgd_saved_index;
195 	*cur_offset = body->lgd_cur_offset;
196 
197 	memcpy(buf, ptr, len);
198 out:
199 	ptlrpc_req_finished(req);
200 err_exit:
201 	LLOG_CLIENT_EXIT(loghandle->lgh_ctxt, imp);
202 	return rc;
203 }
204 
llog_client_prev_block(const struct lu_env * env,struct llog_handle * loghandle,int prev_idx,void * buf,int len)205 static int llog_client_prev_block(const struct lu_env *env,
206 				  struct llog_handle *loghandle,
207 				  int prev_idx, void *buf, int len)
208 {
209 	struct obd_import *imp;
210 	struct ptlrpc_request *req = NULL;
211 	struct llogd_body *body;
212 	void *ptr;
213 	int rc;
214 
215 	LLOG_CLIENT_ENTRY(loghandle->lgh_ctxt, imp);
216 	req = ptlrpc_request_alloc_pack(imp, &RQF_LLOG_ORIGIN_HANDLE_PREV_BLOCK,
217 					LUSTRE_LOG_VERSION,
218 					LLOG_ORIGIN_HANDLE_PREV_BLOCK);
219 	if (req == NULL) {
220 		rc = -ENOMEM;
221 		goto err_exit;
222 	}
223 
224 	body = req_capsule_client_get(&req->rq_pill, &RMF_LLOGD_BODY);
225 	body->lgd_logid = loghandle->lgh_id;
226 	body->lgd_ctxt_idx = loghandle->lgh_ctxt->loc_idx - 1;
227 	body->lgd_llh_flags = loghandle->lgh_hdr->llh_flags;
228 	body->lgd_index = prev_idx;
229 	body->lgd_len = len;
230 
231 	req_capsule_set_size(&req->rq_pill, &RMF_EADATA, RCL_SERVER, len);
232 	ptlrpc_request_set_replen(req);
233 
234 	rc = ptlrpc_queue_wait(req);
235 	if (rc)
236 		goto out;
237 
238 	body = req_capsule_server_get(&req->rq_pill, &RMF_LLOGD_BODY);
239 	if (body == NULL) {
240 		rc = -EFAULT;
241 		goto out;
242 	}
243 
244 	ptr = req_capsule_server_get(&req->rq_pill, &RMF_EADATA);
245 	if (ptr == NULL) {
246 		rc = -EFAULT;
247 		goto out;
248 	}
249 
250 	memcpy(buf, ptr, len);
251 out:
252 	ptlrpc_req_finished(req);
253 err_exit:
254 	LLOG_CLIENT_EXIT(loghandle->lgh_ctxt, imp);
255 	return rc;
256 }
257 
llog_client_read_header(const struct lu_env * env,struct llog_handle * handle)258 static int llog_client_read_header(const struct lu_env *env,
259 				   struct llog_handle *handle)
260 {
261 	struct obd_import *imp;
262 	struct ptlrpc_request *req = NULL;
263 	struct llogd_body *body;
264 	struct llog_log_hdr *hdr;
265 	struct llog_rec_hdr *llh_hdr;
266 	int rc;
267 
268 	LLOG_CLIENT_ENTRY(handle->lgh_ctxt, imp);
269 	req = ptlrpc_request_alloc_pack(imp, &RQF_LLOG_ORIGIN_HANDLE_READ_HEADER,
270 					LUSTRE_LOG_VERSION,
271 					LLOG_ORIGIN_HANDLE_READ_HEADER);
272 	if (req == NULL) {
273 		rc = -ENOMEM;
274 		goto err_exit;
275 	}
276 
277 	body = req_capsule_client_get(&req->rq_pill, &RMF_LLOGD_BODY);
278 	body->lgd_logid = handle->lgh_id;
279 	body->lgd_ctxt_idx = handle->lgh_ctxt->loc_idx - 1;
280 	body->lgd_llh_flags = handle->lgh_hdr->llh_flags;
281 
282 	ptlrpc_request_set_replen(req);
283 	rc = ptlrpc_queue_wait(req);
284 	if (rc)
285 		goto out;
286 
287 	hdr = req_capsule_server_get(&req->rq_pill, &RMF_LLOG_LOG_HDR);
288 	if (hdr == NULL) {
289 		rc = -EFAULT;
290 		goto out;
291 	}
292 
293 	memcpy(handle->lgh_hdr, hdr, sizeof(*hdr));
294 	handle->lgh_last_idx = handle->lgh_hdr->llh_tail.lrt_index;
295 
296 	/* sanity checks */
297 	llh_hdr = &handle->lgh_hdr->llh_hdr;
298 	if (llh_hdr->lrh_type != LLOG_HDR_MAGIC) {
299 		CERROR("bad log header magic: %#x (expecting %#x)\n",
300 		       llh_hdr->lrh_type, LLOG_HDR_MAGIC);
301 		rc = -EIO;
302 	} else if (llh_hdr->lrh_len != LLOG_CHUNK_SIZE) {
303 		CERROR("incorrectly sized log header: %#x (expecting %#x)\n",
304 		       llh_hdr->lrh_len, LLOG_CHUNK_SIZE);
305 		CERROR("you may need to re-run lconf --write_conf.\n");
306 		rc = -EIO;
307 	}
308 out:
309 	ptlrpc_req_finished(req);
310 err_exit:
311 	LLOG_CLIENT_EXIT(handle->lgh_ctxt, imp);
312 	return rc;
313 }
314 
llog_client_close(const struct lu_env * env,struct llog_handle * handle)315 static int llog_client_close(const struct lu_env *env,
316 			     struct llog_handle *handle)
317 {
318 	/* this doesn't call LLOG_ORIGIN_HANDLE_CLOSE because
319 	   the servers all close the file at the end of every
320 	   other LLOG_ RPC. */
321 	return 0;
322 }
323 
324 struct llog_operations llog_client_ops = {
325 	.lop_next_block		= llog_client_next_block,
326 	.lop_prev_block		= llog_client_prev_block,
327 	.lop_read_header	= llog_client_read_header,
328 	.lop_open		= llog_client_open,
329 	.lop_close		= llog_client_close,
330 };
331 EXPORT_SYMBOL(llog_client_ops);
332