fs/afs/cmservice.c

   1 /* AFS Cache Manager Service
   2  *
   3  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/sched.h>
  15 #include <linux/ip.h>
  16 #include "internal.h"
  17 #include "afs_cm.h"
  18
  19 struct workqueue_struct *afs_cm_workqueue;
  20
  21 static int afs_deliver_cb_init_call_back_state(struct afs_call *,
  22                                                struct sk_buff *, bool);
  23 static int afs_deliver_cb_probe(struct afs_call *, struct sk_buff *, bool);
  24 static int afs_deliver_cb_callback(struct afs_call *, struct sk_buff *, bool);
  25 static int afs_deliver_cb_get_capabilities(struct afs_call *, struct sk_buff *,
  26                                            bool);
  27 static void afs_cm_destructor(struct afs_call *);
  28
  29 /*
  30  * CB.CallBack operation type
  31  */
  32 static const struct afs_call_type afs_SRXCBCallBack = {
  33         .name           = "CB.CallBack",
  34         .deliver        = afs_deliver_cb_callback,
  35         .abort_to_error = afs_abort_to_error,
  36         .destructor     = afs_cm_destructor,
  37 };
  38
  39 /*
  40  * CB.InitCallBackState operation type
  41  */
  42 static const struct afs_call_type afs_SRXCBInitCallBackState = {
  43         .name           = "CB.InitCallBackState",
  44         .deliver        = afs_deliver_cb_init_call_back_state,
  45         .abort_to_error = afs_abort_to_error,
  46         .destructor     = afs_cm_destructor,
  47 };
  48
  49 /*
  50  * CB.Probe operation type
  51  */
  52 static const struct afs_call_type afs_SRXCBProbe = {
  53         .name           = "CB.Probe",
  54         .deliver        = afs_deliver_cb_probe,
  55         .abort_to_error = afs_abort_to_error,
  56         .destructor     = afs_cm_destructor,
  57 };
  58
  59 /*
  60  * CB.GetCapabilities operation type
  61  */
  62 static const struct afs_call_type afs_SRXCBGetCapabilites = {
  63         .name           = "CB.GetCapabilities",
  64         .deliver        = afs_deliver_cb_get_capabilities,
  65         .abort_to_error = afs_abort_to_error,
  66         .destructor     = afs_cm_destructor,
  67 };
  68
  69 /*
  70  * route an incoming cache manager call
  71  * - return T if supported, F if not
  72  */
  73 bool afs_cm_incoming_call(struct afs_call *call)
  74 {
  75         u32 operation_id = ntohl(call->operation_ID);
  76
  77         _enter("{CB.OP %u}", operation_id);
  78
  79         switch (operation_id) {
  80         case CBCallBack:
  81                 call->type = &afs_SRXCBCallBack;
  82                 return true;
  83         case CBInitCallBackState:
  84                 call->type = &afs_SRXCBInitCallBackState;
  85                 return true;
  86         case CBProbe:
  87                 call->type = &afs_SRXCBProbe;
  88                 return true;
  89         case CBGetCapabilities:
  90                 call->type = &afs_SRXCBGetCapabilites;
  91                 return true;
  92         default:
  93                 return false;
  94         }
  95 }
  96
  97 /*
  98  * clean up a cache manager call
  99  */
 100 static void afs_cm_destructor(struct afs_call *call)
 101 {
 102         _enter("");
 103
 104         afs_put_server(call->server);
 105         call->server = NULL;
 106         kfree(call->buffer);
 107         call->buffer = NULL;
 108 }
 109
 110 /*
 111  * allow the fileserver to see if the cache manager is still alive
 112  */
 113 static void SRXAFSCB_CallBack(struct work_struct *work)
 114 {
 115         struct afs_call *call = container_of(work, struct afs_call, work);
 116
 117         _enter("");
 118
 119         /* be sure to send the reply *before* attempting to spam the AFS server
 120          * with FSFetchStatus requests on the vnodes with broken callbacks lest
 121          * the AFS server get into a vicious cycle of trying to break further
 122          * callbacks because it hadn't received completion of the CBCallBack op
 123          * yet */
 124         afs_send_empty_reply(call);
 125
 126         afs_break_callbacks(call->server, call->count, call->request);
 127         _leave("");
 128 }
 129
 130 /*
 131  * deliver request data to a CB.CallBack call
 132  */
 133 static int afs_deliver_cb_callback(struct afs_call *call, struct sk_buff *skb,
 134                                    bool last)
 135 {
 136         struct afs_callback *cb;
 137         struct afs_server *server;
 138         struct in_addr addr;
 139         __be32 *bp;
 140         u32 tmp;
 141         int ret, loop;
 142
 143         _enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
 144
 145         switch (call->unmarshall) {
 146         case 0:
 147                 call->offset = 0;
 148                 call->unmarshall++;
 149
 150                 /* extract the FID array and its count in two steps */
 151         case 1:
 152                 _debug("extract FID count");
 153                 ret = afs_extract_data(call, skb, last, &call->tmp, 4);
 154                 switch (ret) {
 155                 case 0:         break;
 156                 case -EAGAIN:   return 0;
 157                 default:        return ret;
 158                 }
 159
 160                 call->count = ntohl(call->tmp);
 161                 _debug("FID count: %u", call->count);
 162                 if (call->count > AFSCBMAX)
 163                         return -EBADMSG;
 164
 165                 call->buffer = kmalloc(call->count * 3 * 4, GFP_KERNEL);
 166                 if (!call->buffer)
 167                         return -ENOMEM;
 168                 call->offset = 0;
 169                 call->unmarshall++;
 170
 171         case 2:
 172                 _debug("extract FID array");
 173                 ret = afs_extract_data(call, skb, last, call->buffer,
 174                                        call->count * 3 * 4);
 175                 switch (ret) {
 176                 case 0:         break;
 177                 case -EAGAIN:   return 0;
 178                 default:        return ret;
 179                 }
 180
 181                 _debug("unmarshall FID array");
 182                 call->request = kcalloc(call->count,
 183                                         sizeof(struct afs_callback),
 184                                         GFP_KERNEL);
 185                 if (!call->request)
 186                         return -ENOMEM;
 187
 188                 cb = call->request;
 189                 bp = call->buffer;
 190                 for (loop = call->count; loop > 0; loop--, cb++) {
 191                         cb->fid.vid     = ntohl(*bp++);
 192                         cb->fid.vnode   = ntohl(*bp++);
 193                         cb->fid.unique  = ntohl(*bp++);
 194                         cb->type        = AFSCM_CB_UNTYPED;
 195                 }
 196
 197                 call->offset = 0;
 198                 call->unmarshall++;
 199
 200                 /* extract the callback array and its count in two steps */
 201         case 3:
 202                 _debug("extract CB count");
 203                 ret = afs_extract_data(call, skb, last, &call->tmp, 4);
 204                 switch (ret) {
 205                 case 0:         break;
 206                 case -EAGAIN:   return 0;
 207                 default:        return ret;
 208                 }
 209
 210                 tmp = ntohl(call->tmp);
 211                 _debug("CB count: %u", tmp);
 212                 if (tmp != call->count && tmp != 0)
 213                         return -EBADMSG;
 214                 call->offset = 0;
 215                 call->unmarshall++;
 216                 if (tmp == 0)
 217                         goto empty_cb_array;
 218
 219         case 4:
 220                 _debug("extract CB array");
 221                 ret = afs_extract_data(call, skb, last, call->request,
 222                                        call->count * 3 * 4);
 223                 switch (ret) {
 224                 case 0:         break;
 225                 case -EAGAIN:   return 0;
 226                 default:        return ret;
 227                 }
 228
 229                 _debug("unmarshall CB array");
 230                 cb = call->request;
 231                 bp = call->buffer;
 232                 for (loop = call->count; loop > 0; loop--, cb++) {
 233                         cb->version     = ntohl(*bp++);
 234                         cb->expiry      = ntohl(*bp++);
 235                         cb->type        = ntohl(*bp++);
 236                 }
 237
 238         empty_cb_array:
 239                 call->offset = 0;
 240                 call->unmarshall++;
 241
 242         case 5:
 243                 _debug("trailer");
 244                 if (skb->len != 0)
 245                         return -EBADMSG;
 246                 break;
 247         }
 248
 249         if (!last)
 250                 return 0;
 251
 252         call->state = AFS_CALL_REPLYING;
 253
 254         /* we'll need the file server record as that tells us which set of
 255          * vnodes to operate upon */
 256         memcpy(&addr, &ip_hdr(skb)->saddr, 4);
 257         server = afs_find_server(&addr);
 258         if (!server)
 259                 return -ENOTCONN;
 260         call->server = server;
 261
 262         INIT_WORK(&call->work, SRXAFSCB_CallBack);
 263         schedule_work(&call->work);
 264         return 0;
 265 }
 266
 267 /*
 268  * allow the fileserver to request callback state (re-)initialisation
 269  */
 270 static void SRXAFSCB_InitCallBackState(struct work_struct *work)
 271 {
 272         struct afs_call *call = container_of(work, struct afs_call, work);
 273
 274         _enter("{%p}", call->server);
 275
 276         afs_init_callback_state(call->server);
 277         afs_send_empty_reply(call);
 278         _leave("");
 279 }
 280
 281 /*
 282  * deliver request data to a CB.InitCallBackState call
 283  */
 284 static int afs_deliver_cb_init_call_back_state(struct afs_call *call,
 285                                                struct sk_buff *skb,
 286                                                bool last)
 287 {
 288         struct afs_server *server;
 289         struct in_addr addr;
 290
 291         _enter(",{%u},%d", skb->len, last);
 292
 293         if (skb->len > 0)
 294                 return -EBADMSG;
 295         if (!last)
 296                 return 0;
 297
 298         /* no unmarshalling required */
 299         call->state = AFS_CALL_REPLYING;
 300
 301         /* we'll need the file server record as that tells us which set of
 302          * vnodes to operate upon */
 303         memcpy(&addr, &ip_hdr(skb)->saddr, 4);
 304         server = afs_find_server(&addr);
 305         if (!server)
 306                 return -ENOTCONN;
 307         call->server = server;
 308
 309         INIT_WORK(&call->work, SRXAFSCB_InitCallBackState);
 310         schedule_work(&call->work);
 311         return 0;
 312 }
 313
 314 /*
 315  * allow the fileserver to see if the cache manager is still alive
 316  */
 317 static void SRXAFSCB_Probe(struct work_struct *work)
 318 {
 319         struct afs_call *call = container_of(work, struct afs_call, work);
 320
 321         _enter("");
 322         afs_send_empty_reply(call);
 323         _leave("");
 324 }
 325
 326 /*
 327  * deliver request data to a CB.Probe call
 328  */
 329 static int afs_deliver_cb_probe(struct afs_call *call, struct sk_buff *skb,
 330                                 bool last)
 331 {
 332         _enter(",{%u},%d", skb->len, last);
 333
 334         if (skb->len > 0)
 335                 return -EBADMSG;
 336         if (!last)
 337                 return 0;
 338
 339         /* no unmarshalling required */
 340         call->state = AFS_CALL_REPLYING;
 341
 342         INIT_WORK(&call->work, SRXAFSCB_Probe);
 343         schedule_work(&call->work);
 344         return 0;
 345 }
 346
 347 /*
 348  * allow the fileserver to ask about the cache manager's capabilities
 349  */
 350 static void SRXAFSCB_GetCapabilities(struct work_struct *work)
 351 {
 352         struct afs_interface *ifs;
 353         struct afs_call *call = container_of(work, struct afs_call, work);
 354         int loop, nifs;
 355
 356         struct {
 357                 struct /* InterfaceAddr */ {
 358                         __be32 nifs;
 359                         __be32 uuid[11];
 360                         __be32 ifaddr[32];
 361                         __be32 netmask[32];
 362                         __be32 mtu[32];
 363                 } ia;
 364                 struct /* Capabilities */ {
 365                         __be32 capcount;
 366                         __be32 caps[1];
 367                 } cap;
 368         } reply;
 369
 370         _enter("");
 371
 372         nifs = 0;
 373         ifs = kcalloc(32, sizeof(*ifs), GFP_KERNEL);
 374         if (ifs) {
 375                 nifs = afs_get_ipv4_interfaces(ifs, 32, false);
 376                 if (nifs < 0) {
 377                         kfree(ifs);
 378                         ifs = NULL;
 379                         nifs = 0;
 380                 }
 381         }
 382
 383         memset(&reply, 0, sizeof(reply));
 384         reply.ia.nifs = htonl(nifs);
 385
 386         reply.ia.uuid[0] = htonl(afs_uuid.time_low);
 387         reply.ia.uuid[1] = htonl(afs_uuid.time_mid);
 388         reply.ia.uuid[2] = htonl(afs_uuid.time_hi_and_version);
 389         reply.ia.uuid[3] = htonl((s8) afs_uuid.clock_seq_hi_and_reserved);
 390         reply.ia.uuid[4] = htonl((s8) afs_uuid.clock_seq_low);
 391         for (loop = 0; loop < 6; loop++)
 392                 reply.ia.uuid[loop + 5] = htonl((s8) afs_uuid.node[loop]);
 393
 394         if (ifs) {
 395                 for (loop = 0; loop < nifs; loop++) {
 396                         reply.ia.ifaddr[loop] = ifs[loop].address.s_addr;
 397                         reply.ia.netmask[loop] = ifs[loop].netmask.s_addr;
 398                         reply.ia.mtu[loop] = htonl(ifs[loop].mtu);
 399                 }
 400         }
 401
 402         reply.cap.capcount = htonl(1);
 403         reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
 404         afs_send_simple_reply(call, &reply, sizeof(reply));
 405
 406         _leave("");
 407 }
 408
 409 /*
 410  * deliver request data to a CB.GetCapabilities call
 411  */
 412 static int afs_deliver_cb_get_capabilities(struct afs_call *call,
 413                                            struct sk_buff *skb, bool last)
 414 {
 415         _enter(",{%u},%d", skb->len, last);
 416
 417         if (skb->len > 0)
 418                 return -EBADMSG;
 419         if (!last)
 420                 return 0;
 421
 422         /* no unmarshalling required */
 423         call->state = AFS_CALL_REPLYING;
 424
 425         INIT_WORK(&call->work, SRXAFSCB_GetCapabilities);
 426         schedule_work(&call->work);
 427         return 0;
 428 }