lustre/ptlrpc/recover.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Lustre Light Super operations
   5  *
   6  * This code is issued under the GNU General Public License.
   7  * See the file COPYING in this distribution
   8  *
   9  * Copryright (C) 1996 Peter J. Braam <braam@stelias.com>
  10  * Copryright (C) 1999 Stelias Computing Inc. <braam@stelias.com>
  11  * Copryright (C) 1999 Seagate Technology Inc.
  12  * Copryright (C) 2001 Mountain View Data, Inc.
  13  * Copryright (C) 2002 Cluster File Systems, Inc.
  14  *
  15  */
  16
  17 #include <linux/config.h>
  18 #include <linux/module.h>
  19 #include <linux/kmod.h>
  20
  21 #define DEBUG_SUBSYSTEM S_LLITE
  22
  23 #include <linux/lustre_lite.h>
  24 #include <linux/lustre_ha.h>
  25
  26 int ll_reconnect(struct ptlrpc_connection *conn)
  27 {
  28         struct ptlrpc_request *request;
  29         struct list_head *tmp;
  30         int rc = -EINVAL;
  31
  32         /* XXX c_lock semantics! */
  33         conn->c_level = LUSTRE_CONN_CON;
  34
  35         /* XXX this code MUST be shared with class_obd_connect! */
  36         list_for_each(tmp, &conn->c_imports) {
  37                 struct obd_import *imp = list_entry(tmp, struct obd_import,
  38                                                     imp_chain);
  39                 struct obd_device *obd = imp->imp_obd;
  40                 struct client_obd *cli = &obd->u.cli;
  41                 int rq_opc = (obd->obd_type->typ_ops->o_brw)
  42                         ? OST_CONNECT : MDS_CONNECT;
  43                 int size[] = { sizeof(cli->cl_target_uuid),
  44                                sizeof(obd->obd_uuid) };
  45                 char *tmp[] = {cli->cl_target_uuid, obd->obd_uuid };
  46                 struct lustre_handle old_hdl;
  47
  48                 LASSERT(imp->imp_connection == conn);
  49                 request = ptlrpc_prep_req(imp, rq_opc, 2, size, tmp);
  50                 request->rq_level = LUSTRE_CONN_NEW;
  51                 request->rq_replen = lustre_msg_size(0, NULL);
  52                 /* XXX are (addr, cookie) right? */
  53                 request->rq_reqmsg->addr = imp->imp_handle.addr;
  54                 request->rq_reqmsg->cookie = imp->imp_handle.cookie;
  55                 rc = ptlrpc_queue_wait(request);
  56                 rc = ptlrpc_check_status(request, rc);
  57                 if (rc) {
  58                         CERROR("cannot connect to %s@%s: rc = %d\n",
  59                                cli->cl_target_uuid, conn->c_remote_uuid, rc);
  60                         ptlrpc_free_req(request);
  61                         GOTO(out_disc, rc = -ENOTCONN);
  62                 }
  63
  64                 old_hdl = imp->imp_handle;
  65                 imp->imp_handle.addr = request->rq_repmsg->addr;
  66                 imp->imp_handle.cookie = request->rq_repmsg->cookie;
  67                 CDEBUG(D_HA, "reconnected to %s@%s (%Lx/%Lx, was %Lx/%Lx)!\n",
  68                        cli->cl_target_uuid, conn->c_remote_uuid,
  69                        imp->imp_handle.addr, imp->imp_handle.cookie,
  70                        old_hdl.addr, old_hdl.cookie);
  71                 ptlrpc_free_req(request);
  72         }
  73         conn->c_level = LUSTRE_CONN_RECOVD;
  74
  75  out_disc:
  76         return rc;
  77 }
  78
  79 static int ll_recover_upcall(struct ptlrpc_connection *conn)
  80 {
  81         char *argv[3];
  82         char *envp[3];
  83         int rc;
  84
  85         ENTRY;
  86         conn->c_level = LUSTRE_CONN_RECOVD;
  87
  88         argv[0] = obd_recovery_upcall;
  89         argv[1] = conn->c_remote_uuid;
  90         argv[2] = NULL;
  91
  92         envp[0] = "HOME=/";
  93         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
  94         envp[2] = NULL;
  95
  96         rc = call_usermodehelper(argv[0], argv, envp);
  97         if (rc < 0) {
  98                 /*
  99                  * Tragically, this will never be run, because call_umh doesn't
 100                  * report errors like -ENOENT to its caller.
 101                  */
 102                 CERROR("Error invoking recovery upcall (%s): %d\n",
 103                        obd_recovery_upcall, rc);
 104                 CERROR("Check /proc/sys/lustre/recovery_upcall?\n");
 105         } else {
 106                 CDEBUG(D_HA, "Invoked upcall %s for connection %s\n",
 107                        argv[0], argv[1]);
 108         }
 109         RETURN(rc);
 110 }
 111
 112 static int ll_recover_reconnect(struct ptlrpc_connection *conn)
 113 {
 114         int rc = 0;
 115         struct list_head *tmp, *pos;
 116         struct ptlrpc_request *req;
 117         ENTRY;
 118
 119         /* 1. reconnect */
 120         rc = ll_reconnect(conn);
 121         if (rc)
 122                 RETURN(rc);
 123
 124         /* 2. walk the request list */
 125         spin_lock(&conn->c_lock);
 126
 127         CDEBUG(D_HA, "connection %p to %s has last_xid "LPD64"\n",
 128                conn, conn->c_remote_uuid, conn->c_last_xid);
 129
 130         list_for_each_safe(tmp, pos, &conn->c_sending_head) {
 131                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 132
 133                 /* replay what needs to be replayed */
 134                 if (req->rq_flags & PTL_RPC_FL_REPLAY) {
 135                         CDEBUG(D_HA, "FL_REPLAY: xid "LPD64" op %d @ %d\n",
 136                                req->rq_xid, req->rq_reqmsg->opc,
 137                                req->rq_import->imp_client->cli_request_portal);
 138                         rc = ptlrpc_replay_req(req);
 139 #if 0
 140 #error We should not hold a spinlock over such a lengthy operation.
 141 #error If necessary, drop spinlock, do operation, re-get spinlock, restart loop.
 142 #error If we need to avoid re-processint items, then delete them from the list
 143 #error as they are replayed and re-add at the tail of this list, so the next
 144 #error item to process will always be at the head of the list.
 145 #endif
 146                         if (rc) {
 147                                 CERROR("recovery replay error %d for req %Ld\n",
 148                                        rc, req->rq_xid);
 149                                 GOTO(out, rc);
 150                         }
 151                 }
 152
 153                 /* server has seen req, we have reply: skip */
 154                 if ((req->rq_flags & PTL_RPC_FL_REPLIED)  &&
 155                     req->rq_xid <= conn->c_last_xid) {
 156                         CDEBUG(D_HA, "REPLIED SKIP: xid "LPD64" op %d @ %d\n",
 157                                req->rq_xid, req->rq_reqmsg->opc,
 158                                req->rq_import->imp_client->cli_request_portal);
 159                         continue;
 160                 }
 161
 162                 /* server has lost req, we have reply: resend, ign reply */
 163                 if ((req->rq_flags & PTL_RPC_FL_REPLIED)  &&
 164                     req->rq_xid > conn->c_last_xid) {
 165                         CDEBUG(D_HA, "REPLIED RESEND: xid "LPD64" op %d @ %d\n",
 166                                req->rq_xid, req->rq_reqmsg->opc,
 167                                req->rq_import->imp_client->cli_request_portal);
 168                         rc = ptlrpc_replay_req(req);
 169                         if (rc) {
 170                                 CERROR("request resend error %d for req %Ld\n",
 171                                        rc, req->rq_xid);
 172                                 GOTO(out, rc);
 173                         }
 174                 }
 175
 176                 /* server has seen req, we have lost reply: -ERESTARTSYS */
 177                 if ( !(req->rq_flags & PTL_RPC_FL_REPLIED)  &&
 178                      req->rq_xid <= conn->c_last_xid) {
 179                         CDEBUG(D_HA, "RESTARTSYS: xid "LPD64" op %d @ %d\n",
 180                                req->rq_xid, req->rq_reqmsg->opc,
 181                                req->rq_import->imp_client->cli_request_portal);
 182                         ptlrpc_restart_req(req);
 183                 }
 184
 185                 /* service has not seen req, no reply: resend */
 186                 if ( !(req->rq_flags & PTL_RPC_FL_REPLIED)  &&
 187                      req->rq_xid > conn->c_last_xid) {
 188                         CDEBUG(D_HA, "RESEND: xid "LPD64" op %d @ %d\n",
 189                                req->rq_xid, req->rq_reqmsg->opc,
 190                                req->rq_import->imp_client->cli_request_portal);
 191                         ptlrpc_resend_req(req);
 192                 }
 193
 194         }
 195
 196         conn->c_level = LUSTRE_CONN_FULL;
 197         recovd_conn_fixed(conn);
 198
 199         CERROR("recovery complete on conn %p(%s), waking delayed reqs\n",
 200                conn, conn->c_remote_uuid);
 201         /* Finally, continue what we delayed since recovery started */
 202         list_for_each_safe(tmp, pos, &conn->c_delayed_head) {
 203                 req = list_entry(tmp, struct ptlrpc_request, rq_list);
 204                 ptlrpc_continue_req(req);
 205         }
 206
 207         EXIT;
 208  out:
 209         spin_unlock(&conn->c_lock);
 210         return rc;
 211 }
 212
 213 static int ll_retry_recovery(struct ptlrpc_connection *conn)
 214 {
 215         CDEBUG(D_HA, "Recovery has failed on conn %p\n", conn);
 216 #if 0
 217         /* XXX use a timer, sideshow bob */
 218         recovd_conn_fail(conn);
 219         /* XXX this is disabled until I fix it so that we don't just keep
 220          * XXX retrying in the case of a missing upcall.
 221          */
 222 #endif
 223         return 0;
 224 }
 225
 226 int ll_recover(struct recovd_data *rd, int phase)
 227 {
 228         struct ptlrpc_connection *conn = class_rd2conn(rd);
 229
 230         LASSERT(conn);
 231         ENTRY;
 232
 233         switch (phase) {
 234             case PTLRPC_RECOVD_PHASE_PREPARE:
 235                 RETURN(ll_recover_upcall(conn));
 236             case PTLRPC_RECOVD_PHASE_RECOVER:
 237                 RETURN(ll_recover_reconnect(conn));
 238             case PTLRPC_RECOVD_PHASE_FAILURE:
 239                 RETURN(ll_retry_recovery(conn));
 240         }
 241
 242         LBUG();
 243         RETURN(-ENOSYS);
 244 }