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.
54 lock_ObtainWrite(&cm_serverLock);
55 for(tsp = cm_allServersp; tsp; tsp = tsp->allNextp) {
57 lock_ReleaseWrite(&cm_serverLock);
59 /* now process the server */
60 lock_ObtainMutex(&tsp->mx);
62 /* what time is it? */
65 serverType = tsp->type;
67 wasDown = tsp->flags & CM_SERVERFLAG_DOWN;
69 /* only do the ping if the cell matches the requested cell, or we're
70 * matching all cells (cellp == NULL), and if we've requested to ping
71 * this type of {up, down} servers.
73 if ((cellp == NULL || cellp == tsp->cellp) &&
74 ((wasDown && (flags & CM_FLAG_CHECKDOWNSERVERS)) ||
75 (!wasDown && (flags & CM_FLAG_CHECKUPSERVERS)))) {
78 } /* we're supposed to check this up/down server */
79 lock_ReleaseMutex(&tsp->mx);
81 /* at this point, we've adjusted the server state, so do the ping and
85 code = cm_ConnByServer(tsp, cm_rootUserp, &connp);
87 /* now call the appropriate ping call. Drop the timeout if
88 * the server is known to be down, so that we don't waste a
89 * lot of time retiming out down servers.
92 rx_SetConnDeadTime(connp->callp, 10);
93 if (serverType == CM_SERVER_VLDB) {
94 code = VL_ProbeServer(connp->callp);
98 code = RXAFS_GetTime(connp->callp, &secs, &usecs);
101 rx_SetConnDeadTime(connp->callp, ConnDeadtimeout);
103 } /* got an unauthenticated connection to this server */
105 lock_ObtainMutex(&tsp->mx);
107 /* mark server as up */
108 tsp->flags &= ~CM_SERVERFLAG_DOWN;
111 /* mark server as down */
112 tsp->flags |= CM_SERVERFLAG_DOWN;
114 lock_ReleaseMutex(&tsp->mx);
117 /* also, run the GC function for connections on all of the
118 * server's connections.
120 cm_GCConnections(tsp);
122 lock_ObtainWrite(&cm_serverLock);
123 osi_assert(tsp->refCount-- > 0);
125 lock_ReleaseWrite(&cm_serverLock);
128 void cm_InitServer(void)
130 static osi_once_t once;
132 if (osi_Once(&once)) {
133 lock_InitializeRWLock(&cm_serverLock, "cm_serverLock");
138 void cm_PutServer(cm_server_t *serverp)
140 lock_ObtainWrite(&cm_serverLock);
141 osi_assert(serverp->refCount-- > 0);
142 lock_ReleaseWrite(&cm_serverLock);
145 void cm_SetServerPrefs(cm_server_t * serverp)
147 unsigned long serverAddr; /* in host byte order */
148 unsigned long myAddr, myNet, mySubnet;/* in host byte order */
149 unsigned long netMask;
152 /* implement server prefs for fileservers only */
153 if ( serverp->type == CM_SERVER_FILE )
155 serverAddr = ntohl(serverp->addr.sin_addr.s_addr);
156 serverp->ipRank = CM_IPRANK_LOW; /* default setings */
158 for ( i=0; i < cm_noIPAddr; i++)
160 /* loop through all the client's IP address and compare
161 ** each of them against the server's IP address */
163 myAddr = cm_IPAddr[i];
164 if ( IN_CLASSA(myAddr) )
165 netMask = IN_CLASSA_NET;
166 else if ( IN_CLASSB(myAddr) )
167 netMask = IN_CLASSB_NET;
168 else if ( IN_CLASSC(myAddr) )
169 netMask = IN_CLASSC_NET;
173 myNet = myAddr & netMask;
174 mySubnet = myAddr & cm_SubnetMask[i];
176 if ( (serverAddr & netMask) == myNet )
178 if ( (serverAddr & cm_SubnetMask[i]) == mySubnet)
180 if ( serverAddr == myAddr )
181 serverp->ipRank = min(serverp->ipRank,
182 CM_IPRANK_TOP);/* same machine */
183 else serverp->ipRank = min(serverp->ipRank,
184 CM_IPRANK_HI); /* same subnet */
186 else serverp->ipRank = min(serverp->ipRank,CM_IPRANK_MED);
189 /* random between 0..15*/
190 serverp->ipRank += min(serverp->ipRank, rand() % 0x000f);
191 } /* and of for loop */
193 else serverp->ipRank = 10000 + (rand() % 0x00ff); /* VL server */
196 cm_server_t *cm_NewServer(struct sockaddr_in *socketp, int type, cm_cell_t *cellp) {
199 osi_assert(socketp->sin_family == AF_INET);
201 tsp = malloc(sizeof(*tsp));
202 memset(tsp, 0, sizeof(*tsp));
206 lock_InitializeMutex(&tsp->mx, "cm_server_t mutex");
207 tsp->addr = *socketp;
209 cm_SetServerPrefs(tsp);
211 lock_ObtainWrite(&cm_serverLock); /* get server lock */
212 tsp->allNextp = cm_allServersp;
213 cm_allServersp = tsp;
214 lock_ReleaseWrite(&cm_serverLock); /* release server lock */
219 /* find a server based on its properties */
220 cm_server_t *cm_FindServer(struct sockaddr_in *addrp, int type)
224 osi_assert(addrp->sin_family == AF_INET);
226 lock_ObtainWrite(&cm_serverLock);
227 for(tsp = cm_allServersp; tsp; tsp=tsp->allNextp) {
228 if (tsp->type == type &&
229 tsp->addr.sin_addr.s_addr == addrp->sin_addr.s_addr) break;
232 /* bump ref count if we found the server */
233 if (tsp) tsp->refCount++;
235 /* drop big table lock */
236 lock_ReleaseWrite(&cm_serverLock);
238 /* return what we found */
242 cm_serverRef_t *cm_NewServerRef(cm_server_t *serverp)
244 cm_serverRef_t *tsrp;
246 lock_ObtainWrite(&cm_serverLock);
248 lock_ReleaseWrite(&cm_serverLock);
249 tsrp = malloc(sizeof(*tsrp));
250 tsrp->server = serverp;
251 tsrp->status = not_busy;
257 long cm_ChecksumServerList(cm_serverRef_t *serversp)
261 cm_serverRef_t *tsrp;
263 lock_ObtainWrite(&cm_serverLock);
265 for (tsrp = serversp; tsrp; tsrp=tsrp->next) {
270 sum ^= (long) tsrp->server;
273 lock_ReleaseWrite(&cm_serverLock);
278 ** Insert a server into the server list keeping the list sorted in
279 ** asending order of ipRank.
281 void cm_InsertServerList(cm_serverRef_t** list, cm_serverRef_t* element)
283 cm_serverRef_t *current=*list;
284 unsigned short ipRank = element->server->ipRank;
286 lock_ObtainWrite(&cm_serverLock);
288 /* insertion into empty list or at the beginning of the list */
289 if ( !current || (current->server->ipRank > ipRank) )
291 element->next = *list;
293 lock_ReleaseWrite(&cm_serverLock);
297 while ( current->next ) /* find appropriate place to insert */
299 if ( current->next->server->ipRank > ipRank )
301 else current = current->next;
303 element->next = current->next;
304 current->next = element;
305 lock_ReleaseWrite(&cm_serverLock);
308 ** Re-sort the server list with the modified rank
309 ** returns 0 if element was changed successfully.
310 ** returns 1 if list remained unchanged.
312 long cm_ChangeRankServer(cm_serverRef_t** list, cm_server_t* server)
314 cm_serverRef_t **current=list;
315 cm_serverRef_t *element=0;
317 /* if there is max of one element in the list, nothing to sort */
318 if ( (!*current) || !((*current)->next) )
319 return 1; /* list unchanged: return success */
321 lock_ObtainWrite(&cm_serverLock);
322 /* if the server is on the list, delete it from list */
325 if ( (*current)->server == server)
327 element = (*current);
328 *current = (*current)->next; /* delete it */
331 current = & ( (*current)->next);
333 lock_ReleaseWrite(&cm_serverLock);
335 /* if this volume is not replicated on this server */
337 return 1; /* server is not on list */
339 /* re-insert deleted element into the list with modified rank*/
340 cm_InsertServerList(list, element);
344 ** If there are more than one server on the list and the first n servers on
345 ** the list have the same rank( n>1), then randomise among the first n servers.
347 void cm_RandomizeServer(cm_serverRef_t** list)
350 cm_serverRef_t* tsrp = *list, *lastTsrp;
351 unsigned short lowestRank;
353 /* an empty list or a list with only one element */
354 if ( !tsrp || ! tsrp->next )
357 lock_ObtainWrite(&cm_serverLock);
359 /* count the number of servers with the lowest rank */
360 lowestRank = tsrp->server->ipRank;
361 for ( count=1, tsrp=tsrp->next; tsrp; tsrp=tsrp->next)
363 if ( tsrp->server->ipRank != lowestRank)
369 /* if there is only one server with the lowest rank, we are done */
371 lock_ReleaseWrite(&cm_serverLock);
375 picked = rand() % count;
377 lock_ReleaseWrite(&cm_serverLock);
382 while (--picked >= 0)
387 lastTsrp->next = tsrp->next; /* delete random element from list*/
388 tsrp->next = *list; /* insert element at the beginning of list */
390 lock_ReleaseWrite(&cm_serverLock);
393 /* call cm_FreeServer while holding a write lock on cm_serverLock */
394 void cm_FreeServer(cm_server_t* server)
396 if (--(server->refCount) == 0)
398 /* we need to check to ensure that all of the connections
399 * for this server have a 0 refCount; otherwise, they will
400 * not be garbage collected
402 cm_GCConnections(&server); /* connsp */
404 lock_FinalizeMutex(&server->mx);
405 if ( cm_allServersp == server )
406 cm_allServersp = server->allNextp;
410 for(tsp = cm_allServersp; tsp->allNextp; tsp=tsp->allNextp) {
411 if ( tsp->allNextp == server ) {
412 tsp->allNextp = server->allNextp;
420 void cm_FreeServerList(cm_serverRef_t** list)
422 cm_serverRef_t *current = *list;
423 cm_serverRef_t *next = 0;
425 lock_ObtainWrite(&cm_serverLock);
429 next = current->next;
430 cm_FreeServer(current->server);
435 lock_ReleaseWrite(&cm_serverLock);