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 void cm_CheckServers(long flags, cm_cell_t *cellp)
34 /* ping all file servers, up or down, with unauthenticated connection,
35 * to find out whether we have all our callbacks from the server still.
36 * Also, ping down VLDBs.
46 struct rx_connection * callp;
48 lock_ObtainWrite(&cm_serverLock);
49 for (tsp = cm_allServersp; tsp; tsp = tsp->allNextp) {
50 cm_GetServerNoLock(tsp);
51 lock_ReleaseWrite(&cm_serverLock);
53 /* now process the server */
54 lock_ObtainMutex(&tsp->mx);
56 serverType = tsp->type;
58 wasDown = tsp->flags & CM_SERVERFLAG_DOWN;
60 /* only do the ping if the cell matches the requested cell, or we're
61 * matching all cells (cellp == NULL), and if we've requested to ping
62 * this type of {up, down} servers.
64 if ((cellp == NULL || cellp == tsp->cellp) &&
65 ((wasDown && (flags & CM_FLAG_CHECKDOWNSERVERS)) ||
66 (!wasDown && (flags & CM_FLAG_CHECKUPSERVERS)))) {
69 } /* we're supposed to check this up/down server */
70 lock_ReleaseMutex(&tsp->mx);
72 /* at this point, we've adjusted the server state, so do the ping and
76 code = cm_ConnByServer(tsp, cm_rootUserp, &connp);
78 /* now call the appropriate ping call. Drop the timeout if
79 * the server is known to be down, so that we don't waste a
80 * lot of time retiming out down servers.
83 rx_SetConnDeadTime(connp->callp, 10);
84 if (serverType == CM_SERVER_VLDB) {
85 code = VL_ProbeServer(connp->callp);
89 callp = cm_GetRxConn(connp);
90 code = RXAFS_GetTime(callp, &secs, &usecs);
91 rx_PutConnection(callp);
94 rx_SetConnDeadTime(connp->callp, ConnDeadtimeout);
96 } /* got an unauthenticated connection to this server */
98 lock_ObtainMutex(&tsp->mx);
100 /* mark server as up */
101 tsp->flags &= ~CM_SERVERFLAG_DOWN;
104 /* mark server as down */
105 tsp->flags |= CM_SERVERFLAG_DOWN;
107 lock_ReleaseMutex(&tsp->mx);
110 /* also, run the GC function for connections on all of the
111 * server's connections.
113 cm_GCConnections(tsp);
115 lock_ObtainWrite(&cm_serverLock);
116 cm_PutServerNoLock(tsp);
118 lock_ReleaseWrite(&cm_serverLock);
121 void cm_InitServer(void)
123 static osi_once_t once;
125 if (osi_Once(&once)) {
126 lock_InitializeRWLock(&cm_serverLock, "cm_serverLock");
131 void cm_GetServer(cm_server_t *serverp)
133 lock_ObtainWrite(&cm_serverLock);
135 lock_ReleaseWrite(&cm_serverLock);
138 void cm_GetServerNoLock(cm_server_t *serverp)
143 void cm_PutServer(cm_server_t *serverp)
145 lock_ObtainWrite(&cm_serverLock);
146 osi_assert(serverp->refCount-- > 0);
147 lock_ReleaseWrite(&cm_serverLock);
150 void cm_PutServerNoLock(cm_server_t *serverp)
152 osi_assert(serverp->refCount-- > 0);
155 void cm_SetServerPrefs(cm_server_t * serverp)
157 unsigned long serverAddr; /* in host byte order */
158 unsigned long myAddr, myNet, mySubnet;/* in host byte order */
159 unsigned long netMask;
162 int cm_noIPAddr; /* number of client network interfaces */
163 int cm_IPAddr[CM_MAXINTERFACE_ADDR]; /* client's IP address in host order */
164 int cm_SubnetMask[CM_MAXINTERFACE_ADDR];/* client's subnet mask in host order*/
165 int cm_NetMtu[CM_MAXINTERFACE_ADDR]; /* client's MTU sizes */
166 int cm_NetFlags[CM_MAXINTERFACE_ADDR]; /* network flags */
169 /* get network related info */
170 cm_noIPAddr = CM_MAXINTERFACE_ADDR;
171 code = syscfg_GetIFInfo(&cm_noIPAddr,
172 cm_IPAddr, cm_SubnetMask,
173 cm_NetMtu, cm_NetFlags);
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 cm_server_t *cm_NewServer(struct sockaddr_in *socketp, int type, cm_cell_t *cellp) {
217 osi_assert(socketp->sin_family == AF_INET);
219 tsp = malloc(sizeof(*tsp));
220 memset(tsp, 0, sizeof(*tsp));
224 lock_InitializeMutex(&tsp->mx, "cm_server_t mutex");
225 tsp->addr = *socketp;
227 cm_SetServerPrefs(tsp);
229 lock_ObtainWrite(&cm_serverLock); /* get server lock */
230 tsp->allNextp = cm_allServersp;
231 cm_allServersp = tsp;
232 lock_ReleaseWrite(&cm_serverLock); /* release server lock */
237 /* find a server based on its properties */
238 cm_server_t *cm_FindServer(struct sockaddr_in *addrp, int type)
242 osi_assert(addrp->sin_family == AF_INET);
244 lock_ObtainWrite(&cm_serverLock);
245 for (tsp = cm_allServersp; tsp; tsp=tsp->allNextp) {
246 if (tsp->type == type &&
247 tsp->addr.sin_addr.s_addr == addrp->sin_addr.s_addr)
251 /* bump ref count if we found the server */
253 cm_GetServerNoLock(tsp);
255 /* drop big table lock */
256 lock_ReleaseWrite(&cm_serverLock);
258 /* return what we found */
262 cm_serverRef_t *cm_NewServerRef(cm_server_t *serverp)
264 cm_serverRef_t *tsrp;
266 cm_GetServer(serverp);
267 tsrp = malloc(sizeof(*tsrp));
268 tsrp->server = serverp;
269 tsrp->status = not_busy;
276 LONG_PTR cm_ChecksumServerList(cm_serverRef_t *serversp)
280 cm_serverRef_t *tsrp;
282 lock_ObtainWrite(&cm_serverLock);
283 for (tsrp = serversp; tsrp; tsrp=tsrp->next) {
288 sum ^= (LONG_PTR) tsrp->server;
291 lock_ReleaseWrite(&cm_serverLock);
296 ** Insert a server into the server list keeping the list sorted in
297 ** asending order of ipRank.
299 ** The refCount of the cm_serverRef_t is increased
301 void cm_InsertServerList(cm_serverRef_t** list, cm_serverRef_t* element)
303 cm_serverRef_t *current=*list;
304 unsigned short ipRank = element->server->ipRank;
306 lock_ObtainWrite(&cm_serverLock);
307 element->refCount++; /* increase refCount */
309 /* insertion into empty list or at the beginning of the list */
310 if ( !current || (current->server->ipRank > ipRank) )
312 element->next = *list;
314 lock_ReleaseWrite(&cm_serverLock);
318 while ( current->next ) /* find appropriate place to insert */
320 if ( current->next->server->ipRank > ipRank )
322 else current = current->next;
324 element->next = current->next;
325 current->next = element;
326 lock_ReleaseWrite(&cm_serverLock);
329 ** Re-sort the server list with the modified rank
330 ** returns 0 if element was changed successfully.
331 ** returns 1 if list remained unchanged.
333 long cm_ChangeRankServer(cm_serverRef_t** list, cm_server_t* server)
335 cm_serverRef_t **current=list;
336 cm_serverRef_t *element=0;
338 /* if there is max of one element in the list, nothing to sort */
339 if ( (!*current) || !((*current)->next) )
340 return 1; /* list unchanged: return success */
342 lock_ObtainWrite(&cm_serverLock);
343 /* if the server is on the list, delete it from list */
346 if ( (*current)->server == server)
348 element = (*current);
349 *current = (*current)->next; /* delete it */
352 current = & ( (*current)->next);
354 lock_ReleaseWrite(&cm_serverLock);
356 /* if this volume is not replicated on this server */
358 return 1; /* server is not on list */
360 /* re-insert deleted element into the list with modified rank*/
361 cm_InsertServerList(list, element);
363 /* reduce refCount which was increased by cm_InsertServerList */
364 lock_ObtainWrite(&cm_serverLock);
366 lock_ReleaseWrite(&cm_serverLock);
370 ** If there are more than one server on the list and the first n servers on
371 ** the list have the same rank( n>1), then randomise among the first n servers.
373 void cm_RandomizeServer(cm_serverRef_t** list)
376 cm_serverRef_t* tsrp = *list, *lastTsrp;
377 unsigned short lowestRank;
379 /* an empty list or a list with only one element */
380 if ( !tsrp || ! tsrp->next )
383 lock_ObtainWrite(&cm_serverLock);
385 /* count the number of servers with the lowest rank */
386 lowestRank = tsrp->server->ipRank;
387 for ( count=1, tsrp=tsrp->next; tsrp; tsrp=tsrp->next)
389 if ( tsrp->server->ipRank != lowestRank)
395 /* if there is only one server with the lowest rank, we are done */
397 lock_ReleaseWrite(&cm_serverLock);
401 picked = rand() % count;
403 lock_ReleaseWrite(&cm_serverLock);
408 while (--picked >= 0)
413 lastTsrp->next = tsrp->next; /* delete random element from list*/
414 tsrp->next = *list; /* insert element at the beginning of list */
416 lock_ReleaseWrite(&cm_serverLock);
419 /* call cm_FreeServer while holding a write lock on cm_serverLock */
420 void cm_FreeServer(cm_server_t* serverp)
422 cm_PutServerNoLock(serverp);
423 if (serverp->refCount == 0)
425 /* we need to check to ensure that all of the connections
426 * for this server have a 0 refCount; otherwise, they will
427 * not be garbage collected
429 cm_GCConnections(serverp); /* connsp */
431 lock_FinalizeMutex(&serverp->mx);
432 if ( cm_allServersp == serverp )
433 cm_allServersp = serverp->allNextp;
437 for(tsp = cm_allServersp; tsp->allNextp; tsp=tsp->allNextp) {
438 if ( tsp->allNextp == serverp ) {
439 tsp->allNextp = serverp->allNextp;
447 void cm_FreeServerList(cm_serverRef_t** list)
449 cm_serverRef_t **current = list;
450 cm_serverRef_t **nextp = 0;
451 cm_serverRef_t * next = 0;
453 lock_ObtainWrite(&cm_serverLock);
457 nextp = &(*current)->next;
458 if (--((*current)->refCount) == 0) {
460 cm_FreeServer((*current)->server);
468 lock_ReleaseWrite(&cm_serverLock);