src/WINNT/afsd/cm_volume.c

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   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
   8  */
   9
  10 #include <afs/param.h>
  11 #include <afs/stds.h>
  12
  13 #ifndef DJGPP
  14 #include <windows.h>
  15 #include <winsock2.h>
  16 #include <nb30.h>
  17 #else
  18 #include <sys/socket.h>
  19 #endif /* !DJGPP */
  20 #include <string.h>
  21 #include <malloc.h>
  22 #include <osi.h>
  23 #include <rx/rx.h>
  24
  25 #include "afsd.h"
  26
  27 osi_rwlock_t cm_volumeLock;
  28 cm_volume_t *cm_allVolumesp;
  29
  30 void cm_InitVolume(void)
  31 {
  32         static osi_once_t once;
  33         if (osi_Once(&once)) {
  34                 lock_InitializeRWLock(&cm_volumeLock, "cm global volume lock");
  35                 cm_allVolumesp = NULL;
  36                 osi_EndOnce(&once);
  37         }
  38 }
  39
  40 /*
  41  * Update a volume.  Caller holds volume's lock (volp->mx).
  42  */
  43 long cm_UpdateVolume(struct cm_cell *cellp, cm_user_t *userp, cm_req_t *reqp,
  44         cm_volume_t *volp)
  45 {
  46         cm_conn_t *connp;
  47         int i;
  48         cm_serverRef_t *tsrp;
  49         cm_server_t *tsp;
  50         struct sockaddr_in tsockAddr;
  51         long tflags;
  52         u_long tempAddr;
  53         struct vldbentry vldbEntry;     /* don't use NVLDB yet; they're not common */
  54         int ROcount = 0;
  55         long code;
  56
  57         /* clear out old bindings */
  58         while (tsrp = volp->rwServersp) {
  59                 volp->rwServersp = tsrp->next;
  60                 cm_PutServer(tsrp->server);
  61                 free(tsrp);
  62         }
  63         while (tsrp = volp->roServersp) {
  64                 volp->roServersp = tsrp->next;
  65                 cm_PutServer(tsrp->server);
  66                 free(tsrp);
  67         }
  68         while (tsrp = volp->bkServersp) {
  69                 volp->bkServersp = tsrp->next;
  70                 cm_PutServer(tsrp->server);
  71                 free(tsrp);
  72         }
  73
  74         /* now we have volume structure locked and held; make RPC to fill it */
  75         do {
  76                 code = cm_ConnByMServers(cellp->vlServersp, userp, reqp,
  77                                          &connp);
  78                 if (code) continue;
  79                 osi_Log1(afsd_logp, "CALL VL_GetEntryByNameO name %s",
  80                          volp->namep);
  81                 code = VL_GetEntryByNameO(connp->callp, volp->namep, &vldbEntry);
  82         } while (cm_Analyze(connp, userp, reqp, NULL, NULL, NULL, code));
  83         code = cm_MapVLRPCError(code, reqp);
  84
  85         if (code == 0) {
  86                 /* decode the response */
  87                 lock_ObtainWrite(&cm_volumeLock);
  88                 if (vldbEntry.flags & VLF_RWEXISTS)
  89                         volp->rwID = vldbEntry.volumeId[0];
  90                 else
  91                         volp->rwID = 0;
  92                 if (vldbEntry.flags & VLF_ROEXISTS)
  93                         volp->roID = vldbEntry.volumeId[1];
  94                 else
  95                         volp->roID = 0;
  96                 if (vldbEntry.flags & VLF_BACKEXISTS)
  97                         volp->bkID = vldbEntry.volumeId[2];
  98                 else
  99                         volp->bkID = 0;
 100                 lock_ReleaseWrite(&cm_volumeLock);
 101                 for(i=0; i<vldbEntry.nServers; i++) {
 102                         /* create a server entry */
 103                         tflags = vldbEntry.serverFlags[i];
 104                         if (tflags & VLSF_DONTUSE) continue;
 105                         tsockAddr.sin_family = AF_INET;
 106                         tempAddr = htonl(vldbEntry.serverNumber[i]);
 107                         tsockAddr.sin_addr.s_addr = tempAddr;
 108                         tsp = cm_FindServer(&tsockAddr, CM_SERVER_FILE);
 109                         if (!tsp)
 110                                 tsp = cm_NewServer(&tsockAddr, CM_SERVER_FILE,
 111                                                    cellp);
 112
 113                         /* if this server was created by fs setserverprefs */
 114                         if ( !tsp->cellp )
 115                                 tsp->cellp = cellp;
 116
 117                         osi_assert(tsp != NULL);
 118
 119                         /* and add it to the list(s). */
 120                         /*
 121                          * Each call to cm_NewServerRef() increments the
 122                          * ref count of tsp.  These reference will be dropped,
 123                          * if and when the volume is reset; see reset code
 124                          * earlier in this function.
 125                          */
 126                         if ((tflags & VLSF_RWVOL)
 127                             && (vldbEntry.flags & VLF_RWEXISTS)) {
 128                                 tsrp = cm_NewServerRef(tsp);
 129                                 tsrp->next = volp->rwServersp;
 130                                 volp->rwServersp = tsrp;
 131                         }
 132                         if ((tflags & VLSF_ROVOL)
 133                             && (vldbEntry.flags & VLF_ROEXISTS)) {
 134                                 tsrp = cm_NewServerRef(tsp);
 135                                 cm_InsertServerList(&volp->roServersp, tsrp);
 136                                 ROcount++;
 137                         }
 138                         /* We don't use VLSF_BACKVOL !?! */
 139                         if ((tflags & VLSF_RWVOL)
 140                             && (vldbEntry.flags & VLF_BACKEXISTS)) {
 141                                 tsrp = cm_NewServerRef(tsp);
 142                                 tsrp->next = volp->bkServersp;
 143                                 volp->bkServersp = tsrp;
 144                         }
 145                         /* Drop the reference obtained by cm_FindServer() */
 146                         cm_PutServer(tsp);
 147                 }
 148
 149                 /*
 150                  * Randomize RO list
 151                  *
 152                  * If the first n servers have the same ipRank, then we
 153                  * randomly pick one among them and move it to the beginning.
 154                  * We don't bother to re-order the whole list because
 155                  * the rest of the list is used only if the first server is
 156                  * down.  We only do this for the RO list; we assume the other
 157                  * lists are length 1.
 158                  */
 159                 if (ROcount > 1) {
 160                         cm_RandomizeServer(&volp->roServersp);
 161                 }
 162         }
 163         return code;
 164 }
 165
 166 long cm_GetVolumeByID(cm_cell_t *cellp, long volumeID, cm_user_t *userp,
 167         cm_req_t *reqp, cm_volume_t **outVolpp)
 168 {
 169         cm_volume_t *volp;
 170         char volNameString[100];
 171         long code;
 172
 173         lock_ObtainWrite(&cm_volumeLock);
 174         for(volp = cm_allVolumesp; volp; volp=volp->nextp) {
 175                 if (cellp == volp->cellp &&
 176                         ((unsigned) volumeID == volp->rwID ||
 177                          (unsigned) volumeID == volp->roID ||
 178                          (unsigned) volumeID == volp->bkID))
 179                                 break;
 180         }
 181
 182         /* hold the volume if we found it */
 183         if (volp) volp->refCount++;
 184         lock_ReleaseWrite(&cm_volumeLock);
 185
 186         /* return it held */
 187         if (volp) {
 188                 lock_ObtainMutex(&volp->mx);
 189
 190                 if (volp->flags & CM_VOLUMEFLAG_RESET) {
 191                         code = cm_UpdateVolume(cellp, userp, reqp, volp);
 192                         if (code == 0) {
 193                                 volp->flags &= ~CM_VOLUMEFLAG_RESET;
 194                         }
 195                 }
 196                 else
 197                         code = 0;
 198                 lock_ReleaseMutex(&volp->mx);
 199                 if (code == 0)
 200                         *outVolpp = volp;
 201                 return code;
 202         }
 203
 204         /* otherwise, we didn't find it so consult the VLDB */
 205         sprintf(volNameString, "%u", volumeID);
 206         code = cm_GetVolumeByName(cellp, volNameString, userp, reqp,
 207                                   0, outVolpp);
 208         return code;
 209 }
 210
 211 long cm_GetVolumeByName(struct cm_cell *cellp, char *volumeNamep,
 212         struct cm_user *userp, struct cm_req *reqp,
 213         long flags, cm_volume_t **outVolpp)
 214 {
 215         cm_volume_t *volp;
 216         long code;
 217
 218         /* initialize this */
 219         code = 0;
 220
 221         lock_ObtainWrite(&cm_volumeLock);
 222         for(volp = cm_allVolumesp; volp; volp=volp->nextp) {
 223                 if (cellp == volp->cellp && strcmp(volumeNamep, volp->namep) == 0) {
 224                         break;
 225                 }
 226         }
 227
 228         /* otherwise, get from VLDB */
 229         if (!volp) {
 230                 volp = malloc(sizeof(*volp));
 231                 memset(volp, 0, sizeof(*volp));
 232                 volp->cellp = cellp;
 233                 volp->nextp = cm_allVolumesp;
 234                 cm_allVolumesp = volp;
 235                 volp->namep = malloc(strlen(volumeNamep)+1);
 236                 strcpy(volp->namep, volumeNamep);
 237                 lock_InitializeMutex(&volp->mx, "cm_volume_t mutex");
 238                 volp->refCount = 1;     /* starts off held */
 239                 volp->flags |= CM_VOLUMEFLAG_RESET;
 240         }
 241         else {
 242                 volp->refCount++;
 243         }
 244
 245         /* next should work since no one could have gotten ptr to this structure yet */
 246         lock_ReleaseWrite(&cm_volumeLock);
 247         lock_ObtainMutex(&volp->mx);
 248
 249         if (volp->flags & CM_VOLUMEFLAG_RESET) {
 250                 code = cm_UpdateVolume(cellp, userp, reqp, volp);
 251                 if (code == 0)
 252                         volp->flags &= ~CM_VOLUMEFLAG_RESET;
 253         }
 254
 255         if (code == 0)
 256                 *outVolpp = volp;
 257         lock_ReleaseMutex(&volp->mx);
 258         return code;
 259 }
 260
 261 void cm_ForceUpdateVolume(cm_fid_t *fidp, cm_user_t *userp, cm_req_t *reqp)
 262 {
 263         cm_cell_t *cellp;
 264         cm_volume_t *volp;
 265         long code;
 266
 267         cellp = cm_FindCellByID(fidp->cell);
 268         if (!cellp) return;
 269
 270         /* search for the volume */
 271         lock_ObtainWrite(&cm_volumeLock);
 272         for(volp = cm_allVolumesp; volp; volp=volp->nextp) {
 273                 if (cellp == volp->cellp &&
 274                         (fidp->volume == volp->rwID ||
 275                          fidp->volume == volp->roID ||
 276                          fidp->volume == volp->bkID))
 277                                 break;
 278         }
 279
 280         /* hold the volume if we found it */
 281         if (volp) volp->refCount++;
 282         lock_ReleaseWrite(&cm_volumeLock);
 283
 284         /* update it */
 285         cm_mountRootGen++;
 286         lock_ObtainMutex(&volp->mx);
 287         volp->flags |= CM_VOLUMEFLAG_RESET;
 288         code = cm_UpdateVolume(cellp, userp, reqp, volp);
 289         if (code == 0)
 290                 volp->flags &= ~CM_VOLUMEFLAG_RESET;
 291         lock_ReleaseMutex(&volp->mx);
 292
 293         cm_PutVolume(volp);
 294 }
 295
 296 /* find the appropriate servers from a volume */
 297 cm_serverRef_t *cm_GetVolServers(cm_volume_t *volp, unsigned long volume)
 298 {
 299         cm_serverRef_t *serversp;
 300
 301         if (volume == volp->rwID)
 302                 serversp = volp->rwServersp;
 303         else if (volume == volp->roID)
 304                 serversp = volp->roServersp;
 305         else if (volume == volp->bkID)
 306                 serversp = volp->bkServersp;
 307         else osi_panic("bad volume ID in cm_GetVolServers", __FILE__, __LINE__);
 308
 309         return serversp;
 310 }
 311
 312 void cm_PutVolume(cm_volume_t *volp)
 313 {
 314         lock_ObtainWrite(&cm_volumeLock);
 315         osi_assert(volp->refCount-- > 0);
 316         lock_ReleaseWrite(&cm_volumeLock);
 317 }
 318
 319 /* return the read-only volume, if there is one, or the read-write volume if
 320  * not.
 321  */
 322 long cm_GetROVolumeID(cm_volume_t *volp)
 323 {
 324         long id;
 325
 326         lock_ObtainMutex(&volp->mx);
 327         if (volp->roID && volp->roServersp)
 328                 id = volp->roID;
 329         else
 330                 id = volp->rwID;
 331         lock_ReleaseMutex(&volp->mx);
 332
 333         return id;
 334 }
 335
 336 void cm_CheckVolumes(void)
 337 {
 338         cm_volume_t *volp;
 339
 340         cm_mountRootGen++;
 341         lock_ObtainWrite(&cm_volumeLock);
 342         for(volp = cm_allVolumesp; volp; volp=volp->nextp) {
 343                 volp->refCount++;
 344                 lock_ReleaseWrite(&cm_volumeLock);
 345                 lock_ObtainMutex(&volp->mx);
 346
 347                 volp->flags |= CM_VOLUMEFLAG_RESET;
 348
 349                 lock_ReleaseMutex(&volp->mx);
 350                 lock_ObtainWrite(&cm_volumeLock);
 351                 osi_assert(volp->refCount-- > 0);
 352         }
 353         lock_ReleaseWrite(&cm_volumeLock);
 354
 355         /* We should also refresh cached mount points */
 356
 357 }
 358
 359 /*
 360 ** Finds all volumes that reside on this server and reorders their
 361 ** RO list according to the changed rank of server.
 362 */
 363 void cm_ChangeRankVolume(cm_server_t       *tsp)
 364 {
 365         int             code;
 366         cm_volume_t*    volp;
 367
 368         /* find volumes which might have RO copy on server*/
 369         lock_ObtainWrite(&cm_volumeLock);
 370         for(volp = cm_allVolumesp; volp; volp=volp->nextp)
 371         {
 372                 code = 1 ;      /* assume that list is unchanged */
 373                 volp->refCount++;
 374                 lock_ReleaseWrite(&cm_volumeLock);
 375                 lock_ObtainMutex(&volp->mx);
 376
 377                 if ((tsp->cellp==volp->cellp) && (volp->roServersp))
 378                     code =cm_ChangeRankServer(&volp->roServersp, tsp);
 379
 380                 /* this volume list was changed */
 381                 if ( !code )
 382                         cm_RandomizeServer(&volp->roServersp);
 383
 384                 lock_ReleaseMutex(&volp->mx);
 385                 lock_ObtainWrite(&cm_volumeLock);
 386                 osi_assert(volp->refCount-- > 0);
 387         }
 388         lock_ReleaseWrite(&cm_volumeLock);
 389 }