lustre/ptlrpc/service.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  Copyright (C) 2002 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  *
  21  */
  22
  23 #define DEBUG_SUBSYSTEM S_RPC
  24
  25 #include <linux/obd_support.h>
  26 #include <linux/obd_class.h>
  27 #include <linux/lustre_net.h>
  28
  29 extern int request_in_callback(ptl_event_t *ev);
  30 extern int ptl_handled_rpc(struct ptlrpc_service *service, void *start);
  31
  32 static int ptlrpc_check_event(struct ptlrpc_service *svc,
  33                               struct ptlrpc_thread *thread, ptl_event_t *event)
  34 {
  35         int rc = 0;
  36         ENTRY;
  37
  38         spin_lock(&svc->srv_lock);
  39         if (thread->t_flags & SVC_STOPPING)
  40                 GOTO(out, rc = 1);
  41
  42         if (ptl_is_valid_handle(&svc->srv_eq_h)) {
  43                 int err;
  44                 err = PtlEQGet(svc->srv_eq_h, event);
  45
  46                 if (err == PTL_OK) {
  47                         thread->t_flags |= SVC_EVENT;
  48                         GOTO(out, rc = 1);
  49                 }
  50
  51                 if (err != PTL_EQ_EMPTY) {
  52                         CERROR("BUG: PtlEQGet returned %d\n", rc);
  53                         LBUG();
  54                 }
  55
  56                 GOTO(out, rc = 0);
  57         }
  58
  59         EXIT;
  60  out:
  61         spin_unlock(&svc->srv_lock);
  62         return rc;
  63 }
  64
  65 struct ptlrpc_service *
  66 ptlrpc_init_svc(__u32 bufsize, int req_portal, int rep_portal, char *uuid,
  67                 svc_handler_t handler)
  68 {
  69         int err;
  70         int rc, i;
  71         struct ptlrpc_service *service;
  72         ENTRY;
  73
  74         OBD_ALLOC(service, sizeof(*service));
  75         if (!service) {
  76                 LBUG();
  77                 RETURN(NULL);
  78         }
  79
  80         spin_lock_init(&service->srv_lock);
  81         INIT_LIST_HEAD(&service->srv_reqs);
  82         INIT_LIST_HEAD(&service->srv_threads);
  83         init_waitqueue_head(&service->srv_waitq);
  84
  85         service->srv_buf_size = bufsize;
  86         service->srv_rep_portal = rep_portal;
  87         service->srv_req_portal = req_portal;
  88         service->srv_handler = handler;
  89
  90         err = kportal_uuid_to_peer(uuid, &service->srv_self);
  91         if (err) {
  92                 CERROR("cannot get peer for uuid '%s'\n", uuid);
  93                 OBD_FREE(service, sizeof(*service));
  94                 RETURN(NULL);
  95         }
  96
  97         service->srv_ring_length = RPC_RING_LENGTH;
  98
  99         rc = PtlEQAlloc(service->srv_self.peer_ni, 1024, request_in_callback,
 100                         &(service->srv_eq_h));
 101
 102         if (rc != PTL_OK) {
 103                 CERROR("PtlEQAlloc failed: %d\n", rc);
 104                 LBUG();
 105                 OBD_FREE(service, sizeof(*service));
 106                 RETURN(NULL);
 107         }
 108
 109         for (i = 0; i < service->srv_ring_length; i++) {
 110                 OBD_ALLOC(service->srv_buf[i], service->srv_buf_size);
 111                 if (service->srv_buf[i] == NULL) {
 112                         CERROR("no memory\n");
 113                         LBUG();
 114                         GOTO(err_ring, NULL);
 115                 }
 116                 service->srv_ref_count[i] = 0;
 117                 ptlrpc_link_svc_me(service, i);
 118         }
 119
 120         CDEBUG(D_NET, "Starting service listening on portal %d\n",
 121                service->srv_req_portal);
 122
 123         RETURN(service);
 124 err_ring:
 125         service->srv_ring_length = i;
 126         ptlrpc_unregister_service(service);
 127         return NULL;
 128 }
 129
 130 static int handle_incoming_request(struct obd_device *obddev,
 131                                    struct ptlrpc_service *svc,
 132                                    ptl_event_t *event)
 133 {
 134         struct ptlrpc_request request;
 135         struct lustre_peer peer;
 136         void *start;
 137         int rc;
 138
 139         /* FIXME: If we move to an event-driven model, we should put the request
 140          * on the stack of mds_handle instead. */
 141         start = event->mem_desc.start;
 142
 143         memset(&request, 0, sizeof(request));
 144         request.rq_svc = svc;
 145         request.rq_obd = obddev;
 146         request.rq_xid = event->match_bits;
 147         request.rq_reqmsg = event->mem_desc.start + event->offset;
 148         request.rq_reqlen = event->mem_desc.length;
 149
 150         if (request.rq_reqlen < sizeof(struct lustre_msg)) {
 151                 CERROR("incomplete request: ptl %d from %Lx xid %Ld\n",
 152                        svc->srv_req_portal, event->initiator.nid,
 153                        request.rq_xid);
 154                 spin_unlock(&svc->srv_lock);
 155                 return -EINVAL;
 156         }
 157
 158         if (request.rq_reqmsg->magic != PTLRPC_MSG_MAGIC) {
 159                 CERROR("wrong lustre_msg magic: ptl %d from %Lx xid %Ld\n",
 160                        svc->srv_req_portal, event->initiator.nid,
 161                        request.rq_xid);
 162                 spin_unlock(&svc->srv_lock);
 163                 return -EINVAL;
 164         }
 165
 166         if (request.rq_reqmsg->version != PTLRPC_MSG_VERSION) {
 167                 CERROR("wrong lustre_msg version: ptl %d from %Lx xid %Ld\n",
 168                        svc->srv_req_portal, event->initiator.nid,
 169                        request.rq_xid);
 170                 spin_unlock(&svc->srv_lock);
 171                 return -EINVAL;
 172         }
 173
 174         CDEBUG(D_NET, "got req %Ld\n", request.rq_xid);
 175
 176         peer.peer_nid = event->initiator.nid;
 177         /* FIXME: this NI should be the incoming NI.
 178          * We don't know how to find that from here. */
 179         peer.peer_ni = svc->srv_self.peer_ni;
 180
 181         request.rq_export = class_conn2export((struct lustre_handle *) request.rq_reqmsg);
 182
 183         if (request.rq_export) {
 184                 request.rq_connection = request.rq_export->exp_connection;
 185                 ptlrpc_connection_addref(request.rq_connection);
 186         } else {
 187                 request.rq_connection = ptlrpc_get_connection(&peer);
 188         }
 189
 190         spin_unlock(&svc->srv_lock);
 191         rc = svc->srv_handler(&request);
 192         ptlrpc_put_connection(request.rq_connection);
 193         ptl_handled_rpc(svc, start);
 194         return rc;
 195 }
 196
 197 void ptlrpc_rotate_reqbufs(struct ptlrpc_service *service,
 198                             ptl_event_t *ev)
 199 {
 200         int index;
 201
 202         for (index = 0; index < service->srv_ring_length; index++)
 203                 if (service->srv_buf[index] == ev->mem_desc.start)
 204                         break;
 205
 206         if (index == service->srv_ring_length)
 207                 LBUG();
 208
 209         service->srv_ref_count[index]++;
 210
 211         if (ptl_is_valid_handle(&ev->unlinked_me)) {
 212                 int idx;
 213
 214                 for (idx = 0; idx < service->srv_ring_length; idx++)
 215                         if (service->srv_me_h[idx].handle_idx ==
 216                             ev->unlinked_me.handle_idx)
 217                                 break;
 218                 if (idx == service->srv_ring_length)
 219                         LBUG();
 220
 221                 CDEBUG(D_NET, "unlinked %d\n", idx);
 222                 ptl_set_inv_handle(&(service->srv_me_h[idx]));
 223
 224                 if (service->srv_ref_count[idx] == 0)
 225                         ptlrpc_link_svc_me(service, idx);
 226         }
 227 }
 228
 229 static int ptlrpc_main(void *arg)
 230 {
 231         int rc;
 232         struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
 233         struct obd_device *obddev = data->dev;
 234         struct ptlrpc_service *svc = data->svc;
 235         struct ptlrpc_thread *thread = data->thread;
 236
 237         ENTRY;
 238
 239         lock_kernel();
 240         daemonize();
 241         spin_lock_irq(&current->sigmask_lock);
 242         sigfillset(&current->blocked);
 243         recalc_sigpending(current);
 244         spin_unlock_irq(&current->sigmask_lock);
 245
 246         sprintf(current->comm, data->name);
 247
 248         /* Record that the thread is running */
 249         thread->t_flags = SVC_RUNNING;
 250         wake_up(&thread->t_ctl_waitq);
 251
 252         /* XXX maintain a list of all managed devices: insert here */
 253
 254         /* And now, loop forever on requests */
 255         while (1) {
 256                 ptl_event_t event;
 257
 258                 wait_event(svc->srv_waitq,
 259                            ptlrpc_check_event(svc, thread, &event));
 260
 261                 spin_lock(&svc->srv_lock);
 262
 263                 if (thread->t_flags & SVC_STOPPING) {
 264                         thread->t_flags &= ~SVC_STOPPING;
 265                         spin_unlock(&svc->srv_lock);
 266                         EXIT;
 267                         break;
 268                 }
 269
 270                 if (thread->t_flags & SVC_EVENT) {
 271                         thread->t_flags &= ~SVC_EVENT;
 272                         ptlrpc_rotate_reqbufs(svc, &event);
 273
 274                         rc = handle_incoming_request(obddev, svc, &event);
 275                         thread->t_flags &= ~SVC_EVENT;
 276                         continue;
 277                 }
 278
 279                 CERROR("unknown break in service");
 280                 spin_unlock(&svc->srv_lock);
 281                 EXIT;
 282                 break;
 283         }
 284
 285         thread->t_flags = SVC_STOPPED;
 286         wake_up(&thread->t_ctl_waitq);
 287         CDEBUG(D_NET, "service thread exiting, process %d\n", current->pid);
 288         return 0;
 289 }
 290
 291 static void ptlrpc_stop_thread(struct ptlrpc_service *svc,
 292                                struct ptlrpc_thread *thread)
 293 {
 294         spin_lock(&svc->srv_lock);
 295         thread->t_flags = SVC_STOPPING;
 296         spin_unlock(&svc->srv_lock);
 297
 298         wake_up(&svc->srv_waitq);
 299         wait_event(thread->t_ctl_waitq, (thread->t_flags & SVC_STOPPED));
 300 }
 301
 302 void ptlrpc_stop_all_threads(struct ptlrpc_service *svc)
 303 {
 304         spin_lock(&svc->srv_lock);
 305         while (!list_empty(&svc->srv_threads)) {
 306                 struct ptlrpc_thread *thread;
 307                 thread = list_entry(svc->srv_threads.next, struct ptlrpc_thread,
 308                                     t_link);
 309                 spin_unlock(&svc->srv_lock);
 310                 ptlrpc_stop_thread(svc, thread);
 311                 spin_lock(&svc->srv_lock);
 312                 list_del(&thread->t_link);
 313                 OBD_FREE(thread, sizeof(*thread));
 314         }
 315         spin_unlock(&svc->srv_lock);
 316 }
 317
 318 int ptlrpc_start_thread(struct obd_device *dev, struct ptlrpc_service *svc,
 319                         char *name)
 320 {
 321         struct ptlrpc_svc_data d;
 322         struct ptlrpc_thread *thread;
 323         int rc;
 324         ENTRY;
 325
 326         OBD_ALLOC(thread, sizeof(*thread));
 327         if (thread == NULL) {
 328                 LBUG();
 329                 RETURN(-ENOMEM);
 330         }
 331         init_waitqueue_head(&thread->t_ctl_waitq);
 332
 333         d.dev = dev;
 334         d.svc = svc;
 335         d.name = name;
 336         d.thread = thread;
 337
 338         spin_lock(&svc->srv_lock);
 339         list_add(&thread->t_link, &svc->srv_threads);
 340         spin_unlock(&svc->srv_lock);
 341
 342         rc = kernel_thread(ptlrpc_main, (void *) &d,
 343                            CLONE_VM | CLONE_FS | CLONE_FILES);
 344         if (rc < 0) {
 345                 CERROR("cannot start thread\n");
 346                 RETURN(-EINVAL);
 347         }
 348         wait_event(thread->t_ctl_waitq, thread->t_flags & SVC_RUNNING);
 349
 350         RETURN(0);
 351 }
 352
 353 int ptlrpc_unregister_service(struct ptlrpc_service *service)
 354 {
 355         int rc, i;
 356
 357         for (i = 0; i < service->srv_ring_length; i++) {
 358                 if (ptl_is_valid_handle(&(service->srv_me_h[i]))) {
 359                         rc = PtlMEUnlink(service->srv_me_h[i]);
 360                         if (rc)
 361                                 CERROR("PtlMEUnlink failed: %d\n", rc);
 362                         ptl_set_inv_handle(&(service->srv_me_h[i]));
 363                 }
 364
 365                 if (service->srv_buf[i] != NULL)
 366                         OBD_FREE(service->srv_buf[i], service->srv_buf_size);
 367                 service->srv_buf[i] = NULL;
 368         }
 369
 370         rc = PtlEQFree(service->srv_eq_h);
 371         if (rc)
 372                 CERROR("PtlEQFree failed: %d\n", rc);
 373
 374         if (!list_empty(&service->srv_reqs)) {
 375                 // XXX reply with errors and clean up
 376                 CERROR("Request list not empty!\n");
 377         }
 378
 379         OBD_FREE(service, sizeof(*service));
 380         return 0;
 381 }