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;
33 cm_PingServer(cm_server_t *tsp)
38 struct rx_connection * callp;
41 Capabilities caps = {0, 0};
43 code = cm_ConnByServer(tsp, cm_rootUserp, &connp);
45 /* now call the appropriate ping call. Drop the timeout if
46 * the server is known to be down, so that we don't waste a
47 * lot of time retiming out down servers.
49 wasDown = tsp->flags & CM_SERVERFLAG_DOWN;
51 rx_SetConnDeadTime(connp->callp, 10);
52 if (tsp->type == CM_SERVER_VLDB) {
53 code = VL_ProbeServer(connp->callp);
57 callp = cm_GetRxConn(connp);
58 code = RXAFS_GetCapabilities(callp, &caps);
59 if (code == RXGEN_OPCODE)
60 code = RXAFS_GetTime(callp, &secs, &usecs);
61 rx_PutConnection(callp);
64 rx_SetConnDeadTime(connp->callp, ConnDeadtimeout);
66 } /* got an unauthenticated connection to this server */
68 lock_ObtainMutex(&tsp->mx);
70 /* mark server as up */
71 tsp->flags &= ~CM_SERVERFLAG_DOWN;
73 /* we currently handle 32-bits of capabilities */
74 if (caps.Capabilities_len > 0) {
75 tsp->capabilities = caps.Capabilities_val[0];
76 free(caps.Capabilities_val);
77 caps.Capabilities_len = 0;
78 caps.Capabilities_val = 0;
80 tsp->capabilities = 0;
84 /* mark server as down */
85 tsp->flags |= CM_SERVERFLAG_DOWN;
86 if (code != VRESTARTING)
87 cm_ForceNewConnections(tsp);
89 lock_ReleaseMutex(&tsp->mx);
93 void cm_CheckServers(long flags, cm_cell_t *cellp)
95 /* ping all file servers, up or down, with unauthenticated connection,
96 * to find out whether we have all our callbacks from the server still.
97 * Also, ping down VLDBs.
103 lock_ObtainWrite(&cm_serverLock);
104 for (tsp = cm_allServersp; tsp; tsp = tsp->allNextp) {
105 cm_GetServerNoLock(tsp);
106 lock_ReleaseWrite(&cm_serverLock);
108 /* now process the server */
109 lock_ObtainMutex(&tsp->mx);
112 isDown = tsp->flags & CM_SERVERFLAG_DOWN;
114 /* only do the ping if the cell matches the requested cell, or we're
115 * matching all cells (cellp == NULL), and if we've requested to ping
116 * this type of {up, down} servers.
118 if ((cellp == NULL || cellp == tsp->cellp) &&
119 ((isDown && (flags & CM_FLAG_CHECKDOWNSERVERS)) ||
120 (!isDown && (flags & CM_FLAG_CHECKUPSERVERS)))) {
122 } /* we're supposed to check this up/down server */
123 lock_ReleaseMutex(&tsp->mx);
125 /* at this point, we've adjusted the server state, so do the ping and
131 /* also, run the GC function for connections on all of the
132 * server's connections.
134 cm_GCConnections(tsp);
136 lock_ObtainWrite(&cm_serverLock);
137 cm_PutServerNoLock(tsp);
139 lock_ReleaseWrite(&cm_serverLock);
142 void cm_InitServer(void)
144 static osi_once_t once;
146 if (osi_Once(&once)) {
147 lock_InitializeRWLock(&cm_serverLock, "cm_serverLock");
152 void cm_GetServer(cm_server_t *serverp)
154 lock_ObtainWrite(&cm_serverLock);
156 lock_ReleaseWrite(&cm_serverLock);
159 void cm_GetServerNoLock(cm_server_t *serverp)
164 void cm_PutServer(cm_server_t *serverp)
166 lock_ObtainWrite(&cm_serverLock);
167 osi_assert(serverp->refCount-- > 0);
168 lock_ReleaseWrite(&cm_serverLock);
171 void cm_PutServerNoLock(cm_server_t *serverp)
173 osi_assert(serverp->refCount-- > 0);
176 void cm_SetServerPrefs(cm_server_t * serverp)
178 unsigned long serverAddr; /* in host byte order */
179 unsigned long myAddr, myNet, mySubnet;/* in host byte order */
180 unsigned long netMask;
183 int cm_noIPAddr; /* number of client network interfaces */
184 int cm_IPAddr[CM_MAXINTERFACE_ADDR]; /* client's IP address in host order */
185 int cm_SubnetMask[CM_MAXINTERFACE_ADDR];/* client's subnet mask in host order*/
186 int cm_NetMtu[CM_MAXINTERFACE_ADDR]; /* client's MTU sizes */
187 int cm_NetFlags[CM_MAXINTERFACE_ADDR]; /* network flags */
190 /* get network related info */
191 cm_noIPAddr = CM_MAXINTERFACE_ADDR;
192 code = syscfg_GetIFInfo(&cm_noIPAddr,
193 cm_IPAddr, cm_SubnetMask,
194 cm_NetMtu, cm_NetFlags);
196 serverAddr = ntohl(serverp->addr.sin_addr.s_addr);
197 serverp->ipRank = CM_IPRANK_LOW; /* default setings */
199 for ( i=0; i < cm_noIPAddr; i++)
201 /* loop through all the client's IP address and compare
202 ** each of them against the server's IP address */
204 myAddr = cm_IPAddr[i];
205 if ( IN_CLASSA(myAddr) )
206 netMask = IN_CLASSA_NET;
207 else if ( IN_CLASSB(myAddr) )
208 netMask = IN_CLASSB_NET;
209 else if ( IN_CLASSC(myAddr) )
210 netMask = IN_CLASSC_NET;
214 myNet = myAddr & netMask;
215 mySubnet = myAddr & cm_SubnetMask[i];
217 if ( (serverAddr & netMask) == myNet )
219 if ( (serverAddr & cm_SubnetMask[i]) == mySubnet)
221 if ( serverAddr == myAddr )
222 serverp->ipRank = min(serverp->ipRank,
223 CM_IPRANK_TOP);/* same machine */
224 else serverp->ipRank = min(serverp->ipRank,
225 CM_IPRANK_HI); /* same subnet */
227 else serverp->ipRank = min(serverp->ipRank,CM_IPRANK_MED);
230 /* random between 0..15*/
231 serverp->ipRank += min(serverp->ipRank, rand() % 0x000f);
232 } /* and of for loop */
235 cm_server_t *cm_NewServer(struct sockaddr_in *socketp, int type, cm_cell_t *cellp) {
238 osi_assert(socketp->sin_family == AF_INET);
240 tsp = malloc(sizeof(*tsp));
241 memset(tsp, 0, sizeof(*tsp));
245 lock_InitializeMutex(&tsp->mx, "cm_server_t mutex");
246 tsp->addr = *socketp;
247 tsp->flags = CM_SERVERFLAG_DOWN; /* assume down; ping will mark up if available */
249 cm_SetServerPrefs(tsp);
251 lock_ObtainWrite(&cm_serverLock); /* get server lock */
252 tsp->allNextp = cm_allServersp;
253 cm_allServersp = tsp;
254 lock_ReleaseWrite(&cm_serverLock); /* release server lock */
256 cm_PingServer(tsp); /* Obtain Capabilities and check up/down state */
260 /* find a server based on its properties */
261 cm_server_t *cm_FindServer(struct sockaddr_in *addrp, int type)
265 osi_assert(addrp->sin_family == AF_INET);
267 lock_ObtainWrite(&cm_serverLock);
268 for (tsp = cm_allServersp; tsp; tsp=tsp->allNextp) {
269 if (tsp->type == type &&
270 tsp->addr.sin_addr.s_addr == addrp->sin_addr.s_addr)
274 /* bump ref count if we found the server */
276 cm_GetServerNoLock(tsp);
278 /* drop big table lock */
279 lock_ReleaseWrite(&cm_serverLock);
281 /* return what we found */
285 cm_serverRef_t *cm_NewServerRef(cm_server_t *serverp)
287 cm_serverRef_t *tsrp;
289 cm_GetServer(serverp);
290 tsrp = malloc(sizeof(*tsrp));
291 tsrp->server = serverp;
292 tsrp->status = not_busy;
299 LONG_PTR cm_ChecksumServerList(cm_serverRef_t *serversp)
303 cm_serverRef_t *tsrp;
305 lock_ObtainWrite(&cm_serverLock);
306 for (tsrp = serversp; tsrp; tsrp=tsrp->next) {
311 sum ^= (LONG_PTR) tsrp->server;
314 lock_ReleaseWrite(&cm_serverLock);
319 ** Insert a server into the server list keeping the list sorted in
320 ** asending order of ipRank.
322 ** The refCount of the cm_serverRef_t is increased
324 void cm_InsertServerList(cm_serverRef_t** list, cm_serverRef_t* element)
326 cm_serverRef_t *current=*list;
327 unsigned short ipRank = element->server->ipRank;
329 lock_ObtainWrite(&cm_serverLock);
330 element->refCount++; /* increase refCount */
332 /* insertion into empty list or at the beginning of the list */
333 if ( !current || (current->server->ipRank > ipRank) )
335 element->next = *list;
337 lock_ReleaseWrite(&cm_serverLock);
341 while ( current->next ) /* find appropriate place to insert */
343 if ( current->next->server->ipRank > ipRank )
345 else current = current->next;
347 element->next = current->next;
348 current->next = element;
349 lock_ReleaseWrite(&cm_serverLock);
352 ** Re-sort the server list with the modified rank
353 ** returns 0 if element was changed successfully.
354 ** returns 1 if list remained unchanged.
356 long cm_ChangeRankServer(cm_serverRef_t** list, cm_server_t* server)
358 cm_serverRef_t **current=list;
359 cm_serverRef_t *element=0;
361 /* if there is max of one element in the list, nothing to sort */
362 if ( (!*current) || !((*current)->next) )
363 return 1; /* list unchanged: return success */
365 lock_ObtainWrite(&cm_serverLock);
366 /* if the server is on the list, delete it from list */
369 if ( (*current)->server == server)
371 element = (*current);
372 *current = (*current)->next; /* delete it */
375 current = & ( (*current)->next);
377 lock_ReleaseWrite(&cm_serverLock);
379 /* if this volume is not replicated on this server */
381 return 1; /* server is not on list */
383 /* re-insert deleted element into the list with modified rank*/
384 cm_InsertServerList(list, element);
386 /* reduce refCount which was increased by cm_InsertServerList */
387 lock_ObtainWrite(&cm_serverLock);
389 lock_ReleaseWrite(&cm_serverLock);
393 ** If there are more than one server on the list and the first n servers on
394 ** the list have the same rank( n>1), then randomise among the first n servers.
396 void cm_RandomizeServer(cm_serverRef_t** list)
399 cm_serverRef_t* tsrp = *list, *lastTsrp;
400 unsigned short lowestRank;
402 /* an empty list or a list with only one element */
403 if ( !tsrp || ! tsrp->next )
406 lock_ObtainWrite(&cm_serverLock);
408 /* count the number of servers with the lowest rank */
409 lowestRank = tsrp->server->ipRank;
410 for ( count=1, tsrp=tsrp->next; tsrp; tsrp=tsrp->next)
412 if ( tsrp->server->ipRank != lowestRank)
418 /* if there is only one server with the lowest rank, we are done */
420 lock_ReleaseWrite(&cm_serverLock);
424 picked = rand() % count;
426 lock_ReleaseWrite(&cm_serverLock);
431 while (--picked >= 0)
436 lastTsrp->next = tsrp->next; /* delete random element from list*/
437 tsrp->next = *list; /* insert element at the beginning of list */
439 lock_ReleaseWrite(&cm_serverLock);
442 /* call cm_FreeServer while holding a write lock on cm_serverLock */
443 void cm_FreeServer(cm_server_t* serverp)
445 cm_PutServerNoLock(serverp);
446 if (serverp->refCount == 0)
448 /* we need to check to ensure that all of the connections
449 * for this server have a 0 refCount; otherwise, they will
450 * not be garbage collected
452 cm_GCConnections(serverp); /* connsp */
454 if (!(serverp->flags & CM_SERVERFLAG_PREF_SET)) {
455 lock_FinalizeMutex(&serverp->mx);
456 if ( cm_allServersp == serverp )
457 cm_allServersp = serverp->allNextp;
461 for(tsp = cm_allServersp; tsp->allNextp; tsp=tsp->allNextp) {
462 if ( tsp->allNextp == serverp ) {
463 tsp->allNextp = serverp->allNextp;
473 void cm_FreeServerList(cm_serverRef_t** list)
475 cm_serverRef_t **current = list;
476 cm_serverRef_t **nextp = 0;
477 cm_serverRef_t * next = 0;
479 lock_ObtainWrite(&cm_serverLock);
483 nextp = &(*current)->next;
484 if (--((*current)->refCount) == 0) {
486 cm_FreeServer((*current)->server);
494 lock_ReleaseWrite(&cm_serverLock);