2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
10 #include <afs/param.h>
18 #include <sys/socket.h>
28 osi_rwlock_t cm_serverLock;
30 cm_server_t *cm_allServersp;
32 int cm_noIPAddr; /* number of client network interfaces */
33 int cm_IPAddr[CM_MAXINTERFACE_ADDR]; /* client's IP address in host order */
34 int cm_SubnetMask[CM_MAXINTERFACE_ADDR];/* client's subnet mask in host order*/
35 int cm_NetMtu[CM_MAXINTERFACE_ADDR]; /* client's MTU sizes */
36 int cm_NetFlags[CM_MAXINTERFACE_ADDR]; /* network flags */
38 void cm_CheckServers(long flags, cm_cell_t *cellp)
40 /* ping all file servers, up or down, with unauthenticated connection,
41 * to find out whether we have all our callbacks from the server still.
42 * Also, ping down VLDBs.
53 struct rx_connection * callp;
55 lock_ObtainWrite(&cm_serverLock);
56 for (tsp = cm_allServersp; tsp; tsp = tsp->allNextp) {
57 cm_GetServerNoLock(tsp);
58 lock_ReleaseWrite(&cm_serverLock);
60 /* now process the server */
61 lock_ObtainMutex(&tsp->mx);
63 /* what time is it? */
66 serverType = tsp->type;
68 wasDown = tsp->flags & CM_SERVERFLAG_DOWN;
70 /* only do the ping if the cell matches the requested cell, or we're
71 * matching all cells (cellp == NULL), and if we've requested to ping
72 * this type of {up, down} servers.
74 if ((cellp == NULL || cellp == tsp->cellp) &&
75 ((wasDown && (flags & CM_FLAG_CHECKDOWNSERVERS)) ||
76 (!wasDown && (flags & CM_FLAG_CHECKUPSERVERS)))) {
79 } /* we're supposed to check this up/down server */
80 lock_ReleaseMutex(&tsp->mx);
82 /* at this point, we've adjusted the server state, so do the ping and
86 code = cm_ConnByServer(tsp, cm_rootUserp, &connp);
88 /* now call the appropriate ping call. Drop the timeout if
89 * the server is known to be down, so that we don't waste a
90 * lot of time retiming out down servers.
93 rx_SetConnDeadTime(connp->callp, 10);
94 if (serverType == CM_SERVER_VLDB) {
95 code = VL_ProbeServer(connp->callp);
99 callp = cm_GetRxConn(connp);
100 code = RXAFS_GetTime(callp, &secs, &usecs);
101 rx_PutConnection(callp);
104 rx_SetConnDeadTime(connp->callp, ConnDeadtimeout);
106 } /* got an unauthenticated connection to this server */
108 lock_ObtainMutex(&tsp->mx);
110 /* mark server as up */
111 tsp->flags &= ~CM_SERVERFLAG_DOWN;
114 /* mark server as down */
115 tsp->flags |= CM_SERVERFLAG_DOWN;
117 lock_ReleaseMutex(&tsp->mx);
120 /* also, run the GC function for connections on all of the
121 * server's connections.
123 cm_GCConnections(tsp);
125 lock_ObtainWrite(&cm_serverLock);
126 cm_PutServerNoLock(tsp);
128 lock_ReleaseWrite(&cm_serverLock);
131 void cm_InitServer(void)
133 static osi_once_t once;
135 if (osi_Once(&once)) {
136 lock_InitializeRWLock(&cm_serverLock, "cm_serverLock");
141 void cm_GetServer(cm_server_t *serverp)
143 lock_ObtainWrite(&cm_serverLock);
145 lock_ReleaseWrite(&cm_serverLock);
148 void cm_GetServerNoLock(cm_server_t *serverp)
153 void cm_PutServer(cm_server_t *serverp)
155 lock_ObtainWrite(&cm_serverLock);
156 osi_assert(serverp->refCount-- > 0);
157 lock_ReleaseWrite(&cm_serverLock);
160 void cm_PutServerNoLock(cm_server_t *serverp)
162 osi_assert(serverp->refCount-- > 0);
165 void cm_SetServerPrefs(cm_server_t * serverp)
167 unsigned long serverAddr; /* in host byte order */
168 unsigned long myAddr, myNet, mySubnet;/* in host byte order */
169 unsigned long netMask;
172 /* implement server prefs for fileservers only */
173 if ( serverp->type == CM_SERVER_FILE )
175 serverAddr = ntohl(serverp->addr.sin_addr.s_addr);
176 serverp->ipRank = CM_IPRANK_LOW; /* default setings */
178 for ( i=0; i < cm_noIPAddr; i++)
180 /* loop through all the client's IP address and compare
181 ** each of them against the server's IP address */
183 myAddr = cm_IPAddr[i];
184 if ( IN_CLASSA(myAddr) )
185 netMask = IN_CLASSA_NET;
186 else if ( IN_CLASSB(myAddr) )
187 netMask = IN_CLASSB_NET;
188 else if ( IN_CLASSC(myAddr) )
189 netMask = IN_CLASSC_NET;
193 myNet = myAddr & netMask;
194 mySubnet = myAddr & cm_SubnetMask[i];
196 if ( (serverAddr & netMask) == myNet )
198 if ( (serverAddr & cm_SubnetMask[i]) == mySubnet)
200 if ( serverAddr == myAddr )
201 serverp->ipRank = min(serverp->ipRank,
202 CM_IPRANK_TOP);/* same machine */
203 else serverp->ipRank = min(serverp->ipRank,
204 CM_IPRANK_HI); /* same subnet */
206 else serverp->ipRank = min(serverp->ipRank,CM_IPRANK_MED);
209 /* random between 0..15*/
210 serverp->ipRank += min(serverp->ipRank, rand() % 0x000f);
211 } /* and of for loop */
214 serverp->ipRank = 10000 + (rand() % 0x00ff); /* VL server */
217 cm_server_t *cm_NewServer(struct sockaddr_in *socketp, int type, cm_cell_t *cellp) {
220 osi_assert(socketp->sin_family == AF_INET);
222 tsp = malloc(sizeof(*tsp));
223 memset(tsp, 0, sizeof(*tsp));
227 lock_InitializeMutex(&tsp->mx, "cm_server_t mutex");
228 tsp->addr = *socketp;
230 cm_SetServerPrefs(tsp);
232 lock_ObtainWrite(&cm_serverLock); /* get server lock */
233 tsp->allNextp = cm_allServersp;
234 cm_allServersp = tsp;
235 lock_ReleaseWrite(&cm_serverLock); /* release server lock */
240 /* find a server based on its properties */
241 cm_server_t *cm_FindServer(struct sockaddr_in *addrp, int type)
245 osi_assert(addrp->sin_family == AF_INET);
247 lock_ObtainWrite(&cm_serverLock);
248 for (tsp = cm_allServersp; tsp; tsp=tsp->allNextp) {
249 if (tsp->type == type &&
250 tsp->addr.sin_addr.s_addr == addrp->sin_addr.s_addr) break;
253 /* bump ref count if we found the server */
255 cm_GetServerNoLock(tsp);
257 /* drop big table lock */
258 lock_ReleaseWrite(&cm_serverLock);
260 /* return what we found */
264 cm_serverRef_t *cm_NewServerRef(cm_server_t *serverp)
266 cm_serverRef_t *tsrp;
268 cm_GetServer(serverp);
269 tsrp = malloc(sizeof(*tsrp));
270 tsrp->server = serverp;
271 tsrp->status = not_busy;
278 long cm_ChecksumServerList(cm_serverRef_t *serversp)
282 cm_serverRef_t *tsrp;
284 lock_ObtainWrite(&cm_serverLock);
285 for (tsrp = serversp; tsrp; tsrp=tsrp->next) {
290 sum ^= (long) tsrp->server;
293 lock_ReleaseWrite(&cm_serverLock);
298 ** Insert a server into the server list keeping the list sorted in
299 ** asending order of ipRank.
301 ** The refCount of the cm_serverRef_t is increased
303 void cm_InsertServerList(cm_serverRef_t** list, cm_serverRef_t* element)
305 cm_serverRef_t *current=*list;
306 unsigned short ipRank = element->server->ipRank;
308 lock_ObtainWrite(&cm_serverLock);
309 element->refCount++; /* increase refCount */
311 /* insertion into empty list or at the beginning of the list */
312 if ( !current || (current->server->ipRank > ipRank) )
314 element->next = *list;
316 lock_ReleaseWrite(&cm_serverLock);
320 while ( current->next ) /* find appropriate place to insert */
322 if ( current->next->server->ipRank > ipRank )
324 else current = current->next;
326 element->next = current->next;
327 current->next = element;
328 lock_ReleaseWrite(&cm_serverLock);
331 ** Re-sort the server list with the modified rank
332 ** returns 0 if element was changed successfully.
333 ** returns 1 if list remained unchanged.
335 long cm_ChangeRankServer(cm_serverRef_t** list, cm_server_t* server)
337 cm_serverRef_t **current=list;
338 cm_serverRef_t *element=0;
340 /* if there is max of one element in the list, nothing to sort */
341 if ( (!*current) || !((*current)->next) )
342 return 1; /* list unchanged: return success */
344 lock_ObtainWrite(&cm_serverLock);
345 /* if the server is on the list, delete it from list */
348 if ( (*current)->server == server)
350 element = (*current);
351 *current = (*current)->next; /* delete it */
354 current = & ( (*current)->next);
356 lock_ReleaseWrite(&cm_serverLock);
358 /* if this volume is not replicated on this server */
360 return 1; /* server is not on list */
362 /* re-insert deleted element into the list with modified rank*/
363 cm_InsertServerList(list, element);
365 /* reduce refCount which was increased by cm_InsertServerList */
366 lock_ObtainWrite(&cm_serverLock);
368 lock_ReleaseWrite(&cm_serverLock);
372 ** If there are more than one server on the list and the first n servers on
373 ** the list have the same rank( n>1), then randomise among the first n servers.
375 void cm_RandomizeServer(cm_serverRef_t** list)
378 cm_serverRef_t* tsrp = *list, *lastTsrp;
379 unsigned short lowestRank;
381 /* an empty list or a list with only one element */
382 if ( !tsrp || ! tsrp->next )
385 lock_ObtainWrite(&cm_serverLock);
387 /* count the number of servers with the lowest rank */
388 lowestRank = tsrp->server->ipRank;
389 for ( count=1, tsrp=tsrp->next; tsrp; tsrp=tsrp->next)
391 if ( tsrp->server->ipRank != lowestRank)
397 /* if there is only one server with the lowest rank, we are done */
399 lock_ReleaseWrite(&cm_serverLock);
403 picked = rand() % count;
405 lock_ReleaseWrite(&cm_serverLock);
410 while (--picked >= 0)
415 lastTsrp->next = tsrp->next; /* delete random element from list*/
416 tsrp->next = *list; /* insert element at the beginning of list */
418 lock_ReleaseWrite(&cm_serverLock);
421 /* call cm_FreeServer while holding a write lock on cm_serverLock */
422 void cm_FreeServer(cm_server_t* serverp)
424 cm_PutServerNoLock(serverp);
425 if (serverp->refCount == 0)
427 /* we need to check to ensure that all of the connections
428 * for this server have a 0 refCount; otherwise, they will
429 * not be garbage collected
431 cm_GCConnections(serverp); /* connsp */
433 lock_FinalizeMutex(&serverp->mx);
434 if ( cm_allServersp == serverp )
435 cm_allServersp = serverp->allNextp;
439 for(tsp = cm_allServersp; tsp->allNextp; tsp=tsp->allNextp) {
440 if ( tsp->allNextp == serverp ) {
441 tsp->allNextp = serverp->allNextp;
449 void cm_FreeServerList(cm_serverRef_t** list)
451 cm_serverRef_t **current = list;
452 cm_serverRef_t **nextp = 0;
453 cm_serverRef_t * next = 0;
455 lock_ObtainWrite(&cm_serverLock);
459 nextp = &(*current)->next;
460 if (--((*current)->refCount) == 0) {
462 cm_FreeServer((*current)->server);
470 lock_ReleaseWrite(&cm_serverLock);