lustre/ptlrpc/llog_client.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2001-2004 Cluster File Systems, Inc.
   5  *   Author: Andreas Dilger <adilger@clusterfs.com>
   6  *
   7  *   This file is part of Lustre, http://www.lustre.org.
   8  *
   9  *   Lustre is free software; you can redistribute it and/or
  10  *   modify it under the terms of version 2 of the GNU General Public
  11  *   License as published by the Free Software Foundation.
  12  *
  13  *   Lustre is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *   GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with Lustre; if not, write to the Free Software
  20  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  *  remote api for llog - client side
  23  *
  24  */
  25
  26 #define DEBUG_SUBSYSTEM S_LOG
  27
  28 #ifndef EXPORT_SYMTAB
  29 #define EXPORT_SYMTAB
  30 #endif
  31
  32 #ifdef __KERNEL__
  33 #include <linux/fs.h>
  34 #else
  35 #include <liblustre.h>
  36 #endif
  37
  38 #include <linux/obd_class.h>
  39 #include <linux/lustre_log.h>
  40 #include <linux/lustre_net.h>
  41 #include <libcfs/list.h>
  42
  43 /* This is a callback from the llog_* functions.
  44  * Assumes caller has already pushed us into the kernel context. */
  45 static int llog_client_create(struct llog_ctxt *ctxt, struct llog_handle **res,
  46                             struct llog_logid *logid, char* fsname ,char *name)
  47 {
  48         struct obd_import *imp;
  49         struct llogd_body req_body;
  50         struct llogd_body *body;
  51         struct llog_handle *handle;
  52         struct ptlrpc_request *req = NULL;
  53         int size[3] = {sizeof(req_body)};
  54         char *tmp[3] = {(char*) &req_body};
  55         int bufcount = 1;
  56         int repsize[] = {sizeof (req_body)};
  57         int rc;
  58         ENTRY;
  59
  60         if (ctxt->loc_imp == NULL) {
  61                 /* This used to be an assert; bug 6200 */
  62                 CERROR("ctxt->loc_imp == NULL for context idx %d.  Unable to "
  63                        "complete MDS/OSS recovery, but I'll try again next "
  64                        "time.  Not fatal.\n", ctxt->loc_idx);
  65                 RETURN(-EINVAL);
  66         }
  67         imp = ctxt->loc_imp;
  68
  69         handle = llog_alloc_handle();
  70         if (handle == NULL)
  71                 RETURN(-ENOMEM);
  72         *res = handle;
  73
  74         memset(&req_body, 0, sizeof(req_body));
  75         if (logid)
  76                 req_body.lgd_logid = *logid;
  77         req_body.lgd_ctxt_idx = ctxt->loc_idx - 1;
  78
  79         if (fsname) {
  80                 size[bufcount] = strlen(fsname) + 1;
  81                 tmp[bufcount] = fsname;
  82                 bufcount++;
  83         }
  84
  85         if (name) {
  86                 size[bufcount] = strlen(name) + 1;
  87                 tmp[bufcount] = name;
  88                 bufcount++;
  89         }
  90
  91         req = ptlrpc_prep_req(imp, LLOG_ORIGIN_HANDLE_CREATE,
  92                               bufcount, size, tmp);
  93         if (!req)
  94                 GOTO(err_free, rc = -ENOMEM);
  95
  96         req->rq_replen = lustre_msg_size(1, repsize);
  97         rc = ptlrpc_queue_wait(req);
  98         if (rc)
  99                 GOTO(err_free, rc);
 100
 101         body = lustre_swab_repbuf(req, 0, sizeof(*body),
 102                                  lustre_swab_llogd_body);
 103         if (body == NULL) {
 104                 CERROR ("Can't unpack llogd_body\n");
 105                 GOTO(err_free, rc =-EFAULT);
 106         }
 107
 108         handle->lgh_id = body->lgd_logid;
 109         handle->lgh_ctxt = ctxt;
 110
 111 out:
 112         if (req)
 113                 ptlrpc_req_finished(req);
 114         RETURN(rc);
 115
 116 err_free:
 117         llog_free_handle(handle);
 118         goto out;
 119 }
 120
 121
 122 static int llog_client_next_block(struct llog_handle *loghandle,
 123                                   int *cur_idx, int next_idx,
 124                                   __u64 *cur_offset, void *buf, int len)
 125 {
 126         struct obd_import *imp = loghandle->lgh_ctxt->loc_imp;
 127         struct ptlrpc_request *req = NULL;
 128         struct llogd_body *body;
 129         void * ptr;
 130         int size = sizeof(*body);
 131         int repsize[2] = {sizeof (*body)};
 132         int rc;
 133         ENTRY;
 134
 135         req = ptlrpc_prep_req(imp, LLOG_ORIGIN_HANDLE_NEXT_BLOCK, 1,&size,NULL);
 136         if (!req)
 137                 GOTO(out, rc = -ENOMEM);
 138
 139         body = lustre_msg_buf(req->rq_reqmsg, 0, sizeof (*body));
 140         body->lgd_logid = loghandle->lgh_id;
 141         body->lgd_ctxt_idx = loghandle->lgh_ctxt->loc_idx - 1;
 142         body->lgd_llh_flags = loghandle->lgh_hdr->llh_flags;
 143         body->lgd_index = next_idx;
 144         body->lgd_saved_index = *cur_idx;
 145         body->lgd_len = len;
 146         body->lgd_cur_offset = *cur_offset;
 147         repsize[1] = len;
 148
 149         req->rq_replen = lustre_msg_size(2, repsize);
 150         rc = ptlrpc_queue_wait(req);
 151         if (rc)
 152                 GOTO(out, rc);
 153
 154         body = lustre_swab_repbuf(req, 0, sizeof(*body),
 155                                  lustre_swab_llogd_body);
 156         if (body == NULL) {
 157                 CERROR ("Can't unpack llogd_body\n");
 158                 GOTO(out, rc =-EFAULT);
 159         }
 160
 161         /* The log records are swabbed as they are processed */
 162         ptr = lustre_msg_buf(req->rq_repmsg, 1, len);
 163         if (ptr == NULL) {
 164                 CERROR ("Can't unpack bitmap\n");
 165                 GOTO(out, rc =-EFAULT);
 166         }
 167
 168         *cur_idx = body->lgd_saved_index;
 169         *cur_offset = body->lgd_cur_offset;
 170
 171         memcpy(buf, ptr, len);
 172
 173 out:
 174         if (req)
 175                 ptlrpc_req_finished(req);
 176         RETURN(rc);
 177 }
 178
 179
 180 static int llog_client_read_header(struct llog_handle *handle)
 181 {
 182         struct obd_import *imp = handle->lgh_ctxt->loc_imp;
 183         struct ptlrpc_request *req = NULL;
 184         struct llogd_body *body;
 185         struct llog_log_hdr *hdr;
 186         struct llog_rec_hdr *llh_hdr;
 187         int size = sizeof(*body);
 188         int repsize = sizeof (*hdr);
 189         int rc;
 190         ENTRY;
 191
 192         req = ptlrpc_prep_req(imp, LLOG_ORIGIN_HANDLE_READ_HEADER,1,&size,NULL);
 193         if (!req)
 194                 GOTO(out, rc = -ENOMEM);
 195
 196         body = lustre_msg_buf(req->rq_reqmsg, 0, sizeof (*body));
 197         body->lgd_logid = handle->lgh_id;
 198         body->lgd_ctxt_idx = handle->lgh_ctxt->loc_idx - 1;
 199         body->lgd_llh_flags = handle->lgh_hdr->llh_flags;
 200
 201         req->rq_replen = lustre_msg_size(1, &repsize);
 202         rc = ptlrpc_queue_wait(req);
 203         if (rc)
 204                 GOTO(out, rc);
 205
 206         hdr = lustre_swab_repbuf(req, 0, sizeof(*hdr), lustre_swab_llog_hdr);
 207         if (hdr == NULL) {
 208                 CERROR ("Can't unpack llog_hdr\n");
 209                 GOTO(out, rc =-EFAULT);
 210         }
 211
 212         memcpy(handle->lgh_hdr, hdr, sizeof (*hdr));
 213         handle->lgh_last_idx = handle->lgh_hdr->llh_tail.lrt_index;
 214
 215         /* sanity checks */
 216         llh_hdr = &handle->lgh_hdr->llh_hdr;
 217         if (llh_hdr->lrh_type != LLOG_HDR_MAGIC) {
 218                 CERROR("bad log header magic: %#x (expecting %#x)\n",
 219                        llh_hdr->lrh_type, LLOG_HDR_MAGIC);
 220                 rc = -EIO;
 221         } else if (llh_hdr->lrh_len != LLOG_CHUNK_SIZE) {
 222                 CERROR("incorrectly sized log header: %#x "
 223                        "(expecting %#x)\n",
 224                        llh_hdr->lrh_len, LLOG_CHUNK_SIZE);
 225                 CERROR("you may need to re-run lconf --write_conf.\n");
 226                 rc = -EIO;
 227         }
 228
 229 out:
 230         if (req)
 231                 ptlrpc_req_finished(req);
 232         RETURN(rc);
 233 }
 234
 235 static int llog_client_close(struct llog_handle *handle)
 236 {
 237         int rc = 0;
 238
 239         RETURN(rc);
 240 }
 241
 242
 243 struct llog_operations llog_client_ops = {
 244         lop_next_block:  llog_client_next_block,
 245         lop_read_header: llog_client_read_header,
 246         lop_create:      llog_client_create,
 247         lop_close:       llog_client_close,
 248 };