kernel/drivers/staging/lustre/lustre/ptlrpc/llog_client.c

   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. */
  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
 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
 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
 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
 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);