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 *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[2] = {sizeof(req_body)};
  54         char *tmp[2] = {(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 (name) {
  80                 size[bufcount] = strlen(name) + 1;
  81                 tmp[bufcount] = name;
  82                 bufcount++;
  83         }
  84
  85         req = ptlrpc_prep_req(imp, LLOG_ORIGIN_HANDLE_CREATE,bufcount,size,tmp);
  86         if (!req)
  87                 GOTO(err_free, rc = -ENOMEM);
  88
  89         req->rq_replen = lustre_msg_size(1, repsize);
  90         rc = ptlrpc_queue_wait(req);
  91         if (rc)
  92                 GOTO(err_free, rc);
  93
  94         body = lustre_swab_repbuf(req, 0, sizeof(*body),
  95                                  lustre_swab_llogd_body);
  96         if (body == NULL) {
  97                 CERROR ("Can't unpack llogd_body\n");
  98                 GOTO(err_free, rc =-EFAULT);
  99         }
 100
 101         handle->lgh_id = body->lgd_logid;
 102         handle->lgh_ctxt = ctxt;
 103
 104 out:
 105         if (req)
 106                 ptlrpc_req_finished(req);
 107         RETURN(rc);
 108
 109 err_free:
 110         llog_free_handle(handle);
 111         goto out;
 112 }
 113
 114
 115 static int llog_client_next_block(struct llog_handle *loghandle,
 116                                   int *cur_idx, int next_idx,
 117                                   __u64 *cur_offset, void *buf, int len)
 118 {
 119         struct obd_import *imp = loghandle->lgh_ctxt->loc_imp;
 120         struct ptlrpc_request *req = NULL;
 121         struct llogd_body *body;
 122         void * ptr;
 123         int size = sizeof(*body);
 124         int repsize[2] = {sizeof (*body)};
 125         int rc;
 126         ENTRY;
 127
 128         req = ptlrpc_prep_req(imp, LLOG_ORIGIN_HANDLE_NEXT_BLOCK, 1,&size,NULL);
 129         if (!req)
 130                 GOTO(out, rc = -ENOMEM);
 131
 132         body = lustre_msg_buf(req->rq_reqmsg, 0, sizeof (*body));
 133         body->lgd_logid = loghandle->lgh_id;
 134         body->lgd_ctxt_idx = loghandle->lgh_ctxt->loc_idx - 1;
 135         body->lgd_llh_flags = loghandle->lgh_hdr->llh_flags;
 136         body->lgd_index = next_idx;
 137         body->lgd_saved_index = *cur_idx;
 138         body->lgd_len = len;
 139         body->lgd_cur_offset = *cur_offset;
 140         repsize[1] = len;
 141
 142         req->rq_replen = lustre_msg_size(2, repsize);
 143         rc = ptlrpc_queue_wait(req);
 144         if (rc)
 145                 GOTO(out, rc);
 146
 147         body = lustre_swab_repbuf(req, 0, sizeof(*body),
 148                                  lustre_swab_llogd_body);
 149         if (body == NULL) {
 150                 CERROR ("Can't unpack llogd_body\n");
 151                 GOTO(out, rc =-EFAULT);
 152         }
 153
 154         /* The log records are swabbed as they are processed */
 155         ptr = lustre_msg_buf(req->rq_repmsg, 1, len);
 156         if (ptr == NULL) {
 157                 CERROR ("Can't unpack bitmap\n");
 158                 GOTO(out, rc =-EFAULT);
 159         }
 160
 161         *cur_idx = body->lgd_saved_index;
 162         *cur_offset = body->lgd_cur_offset;
 163
 164         memcpy(buf, ptr, len);
 165
 166 out:
 167         if (req)
 168                 ptlrpc_req_finished(req);
 169         RETURN(rc);
 170 }
 171
 172
 173 static int llog_client_read_header(struct llog_handle *handle)
 174 {
 175         struct obd_import *imp = handle->lgh_ctxt->loc_imp;
 176         struct ptlrpc_request *req = NULL;
 177         struct llogd_body *body;
 178         struct llog_log_hdr *hdr;
 179         struct llog_rec_hdr *llh_hdr;
 180         int size = sizeof(*body);
 181         int repsize = sizeof (*hdr);
 182         int rc;
 183         ENTRY;
 184
 185         req = ptlrpc_prep_req(imp, LLOG_ORIGIN_HANDLE_READ_HEADER,1,&size,NULL);
 186         if (!req)
 187                 GOTO(out, rc = -ENOMEM);
 188
 189         body = lustre_msg_buf(req->rq_reqmsg, 0, sizeof (*body));
 190         body->lgd_logid = handle->lgh_id;
 191         body->lgd_ctxt_idx = handle->lgh_ctxt->loc_idx - 1;
 192         body->lgd_llh_flags = handle->lgh_hdr->llh_flags;
 193
 194         req->rq_replen = lustre_msg_size(1, &repsize);
 195         rc = ptlrpc_queue_wait(req);
 196         if (rc)
 197                 GOTO(out, rc);
 198
 199         hdr = lustre_swab_repbuf(req, 0, sizeof(*hdr), lustre_swab_llog_hdr);
 200         if (hdr == NULL) {
 201                 CERROR ("Can't unpack llog_hdr\n");
 202                 GOTO(out, rc =-EFAULT);
 203         }
 204
 205         memcpy(handle->lgh_hdr, hdr, sizeof (*hdr));
 206         handle->lgh_last_idx = handle->lgh_hdr->llh_tail.lrt_index;
 207
 208         /* sanity checks */
 209         llh_hdr = &handle->lgh_hdr->llh_hdr;
 210         if (llh_hdr->lrh_type != LLOG_HDR_MAGIC) {
 211                 CERROR("bad log header magic: %#x (expecting %#x)\n",
 212                        llh_hdr->lrh_type, LLOG_HDR_MAGIC);
 213                 rc = -EIO;
 214         } else if (llh_hdr->lrh_len != LLOG_CHUNK_SIZE) {
 215                 CERROR("incorrectly sized log header: %#x "
 216                        "(expecting %#x)\n",
 217                        llh_hdr->lrh_len, LLOG_CHUNK_SIZE);
 218                 CERROR("you may need to re-run lconf --write_conf.\n");
 219                 rc = -EIO;
 220         }
 221
 222 out:
 223         if (req)
 224                 ptlrpc_req_finished(req);
 225         RETURN(rc);
 226 }
 227
 228 static int llog_client_close(struct llog_handle *handle)
 229 {
 230         int rc = 0;
 231
 232         RETURN(rc);
 233 }
 234
 235
 236 struct llog_operations llog_client_ops = {
 237         lop_next_block:  llog_client_next_block,
 238         lop_read_header: llog_client_read_header,
 239         lop_create:      llog_client_create,
 240         lop_close:       llog_client_close,
 241 };