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         LASSERT ((event->mem_desc.options & PTL_MD_IOV) == 0);
 142         start = event->mem_desc.start;
 143
 144         memset(&request, 0, sizeof(request));
 145         request.rq_svc = svc;
 146         request.rq_obd = obddev;
 147         request.rq_xid = event->match_bits;
 148         request.rq_reqmsg = event->mem_desc.start + event->offset;
 149         request.rq_reqlen = event->mem_desc.length;
 150
 151         if (request.rq_reqlen < sizeof(struct lustre_msg)) {
 152                 CERROR("incomplete request (%d): ptl %d from %Lx xid %Ld\n",
 153                        request.rq_reqlen, svc->srv_req_portal,
 154                        event->initiator.nid, request.rq_xid);
 155                 spin_unlock(&svc->srv_lock);
 156                 return -EINVAL;
 157         }
 158
 159         if (request.rq_reqmsg->magic != PTLRPC_MSG_MAGIC) {
 160                 CERROR("wrong lustre_msg magic %d: ptl %d from %Lx xid %Ld\n",
 161                        request.rq_reqmsg->magic, svc->srv_req_portal,
 162                        event->initiator.nid, request.rq_xid);
 163                 spin_unlock(&svc->srv_lock);
 164                 return -EINVAL;
 165         }
 166
 167         if (request.rq_reqmsg->version != PTLRPC_MSG_VERSION) {
 168                 CERROR("wrong lustre_msg version %d: ptl %d from %Lx xid %Ld\n",
 169                        request.rq_reqmsg->version, svc->srv_req_portal,
 170                        event->initiator.nid, request.rq_xid);
 171                 spin_unlock(&svc->srv_lock);
 172                 return -EINVAL;
 173         }
 174
 175         CDEBUG(D_NET, "got req %Ld\n", request.rq_xid);
 176
 177         peer.peer_nid = event->initiator.nid;
 178         /* FIXME: this NI should be the incoming NI.
 179          * We don't know how to find that from here. */
 180         peer.peer_ni = svc->srv_self.peer_ni;
 181
 182         request.rq_export = class_conn2export((struct lustre_handle *) request.rq_reqmsg);
 183
 184         if (request.rq_export) {
 185                 request.rq_connection = request.rq_export->exp_connection;
 186                 ptlrpc_connection_addref(request.rq_connection);
 187         } else {
 188                 request.rq_connection = ptlrpc_get_connection(&peer);
 189         }
 190
 191         spin_unlock(&svc->srv_lock);
 192         rc = svc->srv_handler(&request);
 193         ptlrpc_put_connection(request.rq_connection);
 194         ptl_handled_rpc(svc, start);
 195         return rc;
 196 }
 197
 198 void ptlrpc_rotate_reqbufs(struct ptlrpc_service *service,
 199                             ptl_event_t *ev)
 200 {
 201         int index;
 202
 203         LASSERT ((ev->mem_desc.options & PTL_MD_IOV) == 0);
 204
 205         for (index = 0; index < service->srv_ring_length; index++)
 206                 if (service->srv_buf[index] == ev->mem_desc.start)
 207                         break;
 208
 209         if (index == service->srv_ring_length)
 210                 LBUG();
 211
 212         service->srv_ref_count[index]++;
 213
 214         if (ptl_is_valid_handle(&ev->unlinked_me)) {
 215                 int idx;
 216
 217                 for (idx = 0; idx < service->srv_ring_length; idx++)
 218                         if (service->srv_me_h[idx].handle_idx ==
 219                             ev->unlinked_me.handle_idx)
 220                                 break;
 221                 if (idx == service->srv_ring_length)
 222                         LBUG();
 223
 224                 CDEBUG(D_NET, "unlinked %d\n", idx);
 225                 ptl_set_inv_handle(&(service->srv_me_h[idx]));
 226
 227                 if (service->srv_ref_count[idx] == 0)
 228                         ptlrpc_link_svc_me(service, idx);
 229         }
 230 }
 231
 232 static int ptlrpc_main(void *arg)
 233 {
 234         int rc;
 235         struct ptlrpc_svc_data *data = (struct ptlrpc_svc_data *)arg;
 236         struct obd_device *obddev = data->dev;
 237         struct ptlrpc_service *svc = data->svc;
 238         struct ptlrpc_thread *thread = data->thread;
 239
 240         ENTRY;
 241
 242         lock_kernel();
 243         daemonize();
 244         spin_lock_irq(&current->sigmask_lock);
 245         sigfillset(&current->blocked);
 246         recalc_sigpending(current);
 247         spin_unlock_irq(&current->sigmask_lock);
 248
 249         sprintf(current->comm, data->name);
 250
 251         /* Record that the thread is running */
 252         thread->t_flags = SVC_RUNNING;
 253         wake_up(&thread->t_ctl_waitq);
 254
 255         /* XXX maintain a list of all managed devices: insert here */
 256
 257         /* And now, loop forever on requests */
 258         while (1) {
 259                 ptl_event_t event;
 260
 261                 wait_event(svc->srv_waitq,
 262                            ptlrpc_check_event(svc, thread, &event));
 263
 264                 spin_lock(&svc->srv_lock);
 265
 266                 if (thread->t_flags & SVC_STOPPING) {
 267                         thread->t_flags &= ~SVC_STOPPING;
 268                         spin_unlock(&svc->srv_lock);
 269                         EXIT;
 270                         break;
 271                 }
 272
 273                 if (thread->t_flags & SVC_EVENT) {
 274                         thread->t_flags &= ~SVC_EVENT;
 275                         ptlrpc_rotate_reqbufs(svc, &event);
 276
 277                         rc = handle_incoming_request(obddev, svc, &event);
 278                         thread->t_flags &= ~SVC_EVENT;
 279                         continue;
 280                 }
 281
 282                 CERROR("unknown break in service");
 283                 spin_unlock(&svc->srv_lock);
 284                 EXIT;
 285                 break;
 286         }
 287
 288         thread->t_flags = SVC_STOPPED;
 289         wake_up(&thread->t_ctl_waitq);
 290         CDEBUG(D_NET, "service thread exiting, process %d\n", current->pid);
 291         return 0;
 292 }
 293
 294 static void ptlrpc_stop_thread(struct ptlrpc_service *svc,
 295                                struct ptlrpc_thread *thread)
 296 {
 297         spin_lock(&svc->srv_lock);
 298         thread->t_flags = SVC_STOPPING;
 299         spin_unlock(&svc->srv_lock);
 300
 301         wake_up(&svc->srv_waitq);
 302         wait_event(thread->t_ctl_waitq, (thread->t_flags & SVC_STOPPED));
 303 }
 304
 305 void ptlrpc_stop_all_threads(struct ptlrpc_service *svc)
 306 {
 307         spin_lock(&svc->srv_lock);
 308         while (!list_empty(&svc->srv_threads)) {
 309                 struct ptlrpc_thread *thread;
 310                 thread = list_entry(svc->srv_threads.next, struct ptlrpc_thread,
 311                                     t_link);
 312                 spin_unlock(&svc->srv_lock);
 313                 ptlrpc_stop_thread(svc, thread);
 314                 spin_lock(&svc->srv_lock);
 315                 list_del(&thread->t_link);
 316                 OBD_FREE(thread, sizeof(*thread));
 317         }
 318         spin_unlock(&svc->srv_lock);
 319 }
 320
 321 int ptlrpc_start_thread(struct obd_device *dev, struct ptlrpc_service *svc,
 322                         char *name)
 323 {
 324         struct ptlrpc_svc_data d;
 325         struct ptlrpc_thread *thread;
 326         int rc;
 327         ENTRY;
 328
 329         OBD_ALLOC(thread, sizeof(*thread));
 330         if (thread == NULL) {
 331                 LBUG();
 332                 RETURN(-ENOMEM);
 333         }
 334         init_waitqueue_head(&thread->t_ctl_waitq);
 335
 336         d.dev = dev;
 337         d.svc = svc;
 338         d.name = name;
 339         d.thread = thread;
 340
 341         spin_lock(&svc->srv_lock);
 342         list_add(&thread->t_link, &svc->srv_threads);
 343         spin_unlock(&svc->srv_lock);
 344
 345         rc = kernel_thread(ptlrpc_main, (void *) &d,
 346                            CLONE_VM | CLONE_FS | CLONE_FILES);
 347         if (rc < 0) {
 348                 CERROR("cannot start thread\n");
 349                 RETURN(-EINVAL);
 350         }
 351         wait_event(thread->t_ctl_waitq, thread->t_flags & SVC_RUNNING);
 352
 353         RETURN(0);
 354 }
 355
 356 int ptlrpc_unregister_service(struct ptlrpc_service *service)
 357 {
 358         int rc, i;
 359
 360         for (i = 0; i < service->srv_ring_length; i++) {
 361                 if (ptl_is_valid_handle(&(service->srv_me_h[i]))) {
 362                         rc = PtlMEUnlink(service->srv_me_h[i]);
 363                         if (rc)
 364                                 CERROR("PtlMEUnlink failed: %d\n", rc);
 365                         ptl_set_inv_handle(&(service->srv_me_h[i]));
 366                 }
 367
 368                 if (service->srv_buf[i] != NULL)
 369                         OBD_FREE(service->srv_buf[i], service->srv_buf_size);
 370                 service->srv_buf[i] = NULL;
 371         }
 372
 373         rc = PtlEQFree(service->srv_eq_h);
 374         if (rc)
 375                 CERROR("PtlEQFree failed: %d\n", rc);
 376
 377         if (!list_empty(&service->srv_reqs)) {
 378                 // XXX reply with errors and clean up
 379                 CERROR("Request list not empty!\n");
 380         }
 381
 382         OBD_FREE(service, sizeof(*service));
 383         return 0;
 384 }