fs/nfs/nfs4state.c

   1 /*
   2  *  fs/nfs/nfs4state.c
   3  *
   4  *  Client-side XDR for NFSv4.
   5  *
   6  *  Copyright (c) 2002 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Kendrick Smith <kmsmith@umich.edu>
  10  *
  11  *  Redistribution and use in source and binary forms, with or without
  12  *  modification, are permitted provided that the following conditions
  13  *  are met:
  14  *
  15  *  1. Redistributions of source code must retain the above copyright
  16  *     notice, this list of conditions and the following disclaimer.
  17  *  2. Redistributions in binary form must reproduce the above copyright
  18  *     notice, this list of conditions and the following disclaimer in the
  19  *     documentation and/or other materials provided with the distribution.
  20  *  3. Neither the name of the University nor the names of its
  21  *     contributors may be used to endorse or promote products derived
  22  *     from this software without specific prior written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  25  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  26  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  27  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  31  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  * Implementation of the NFSv4 state model.  For the time being,
  37  * this is minimal, but will be made much more complex in a
  38  * subsequent patch.
  39  */
  40
  41 #include <linux/config.h>
  42 #include <linux/slab.h>
  43 #include <linux/smp_lock.h>
  44 #include <linux/nfs_fs.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/workqueue.h>
  47 #include <linux/bitops.h>
  48
  49 #include "callback.h"
  50 #include "delegation.h"
  51
  52 #define OPENOWNER_POOL_SIZE     8
  53
  54 static spinlock_t               state_spinlock = SPIN_LOCK_UNLOCKED;
  55
  56 nfs4_stateid zero_stateid;
  57
  58 #if 0
  59 nfs4_stateid one_stateid =
  60         { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
  61 #endif
  62
  63 static LIST_HEAD(nfs4_clientid_list);
  64
  65 static void nfs4_recover_state(void *);
  66 extern void nfs4_renew_state(void *);
  67
  68 void
  69 init_nfsv4_state(struct nfs_server *server)
  70 {
  71         server->nfs4_state = NULL;
  72         INIT_LIST_HEAD(&server->nfs4_siblings);
  73 }
  74
  75 void
  76 destroy_nfsv4_state(struct nfs_server *server)
  77 {
  78         if (server->mnt_path) {
  79                 kfree(server->mnt_path);
  80                 server->mnt_path = NULL;
  81         }
  82         if (server->nfs4_state) {
  83                 nfs4_put_client(server->nfs4_state);
  84                 server->nfs4_state = NULL;
  85         }
  86 }
  87
  88 /*
  89  * nfs4_get_client(): returns an empty client structure
  90  * nfs4_put_client(): drops reference to client structure
  91  *
  92  * Since these are allocated/deallocated very rarely, we don't
  93  * bother putting them in a slab cache...
  94  */
  95 static struct nfs4_client *
  96 nfs4_alloc_client(struct in_addr *addr)
  97 {
  98         struct nfs4_client *clp;
  99
 100         if (nfs_callback_up() < 0)
 101                 return NULL;
 102         if ((clp = kmalloc(sizeof(*clp), GFP_KERNEL)) == NULL) {
 103                 nfs_callback_down();
 104                 return NULL;
 105         }
 106         memset(clp, 0, sizeof(*clp));
 107         memcpy(&clp->cl_addr, addr, sizeof(clp->cl_addr));
 108         init_rwsem(&clp->cl_sem);
 109         INIT_LIST_HEAD(&clp->cl_delegations);
 110         INIT_LIST_HEAD(&clp->cl_state_owners);
 111         INIT_LIST_HEAD(&clp->cl_unused);
 112         spin_lock_init(&clp->cl_lock);
 113         atomic_set(&clp->cl_count, 1);
 114         INIT_WORK(&clp->cl_recoverd, nfs4_recover_state, clp);
 115         INIT_WORK(&clp->cl_renewd, nfs4_renew_state, clp);
 116         INIT_LIST_HEAD(&clp->cl_superblocks);
 117         init_waitqueue_head(&clp->cl_waitq);
 118         rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS4 client");
 119         clp->cl_state = 1 << NFS4CLNT_OK;
 120         return clp;
 121 }
 122
 123 static void
 124 nfs4_free_client(struct nfs4_client *clp)
 125 {
 126         struct nfs4_state_owner *sp;
 127
 128         while (!list_empty(&clp->cl_unused)) {
 129                 sp = list_entry(clp->cl_unused.next,
 130                                 struct nfs4_state_owner,
 131                                 so_list);
 132                 list_del(&sp->so_list);
 133                 kfree(sp);
 134         }
 135         BUG_ON(!list_empty(&clp->cl_state_owners));
 136         if (clp->cl_cred)
 137                 put_rpccred(clp->cl_cred);
 138         nfs_idmap_delete(clp);
 139         if (clp->cl_rpcclient)
 140                 rpc_shutdown_client(clp->cl_rpcclient);
 141         kfree(clp);
 142         nfs_callback_down();
 143 }
 144
 145 static struct nfs4_client *__nfs4_find_client(struct in_addr *addr)
 146 {
 147         struct nfs4_client *clp;
 148         list_for_each_entry(clp, &nfs4_clientid_list, cl_servers) {
 149                 if (memcmp(&clp->cl_addr, addr, sizeof(clp->cl_addr)) == 0) {
 150                         atomic_inc(&clp->cl_count);
 151                         return clp;
 152                 }
 153         }
 154         return NULL;
 155 }
 156
 157 struct nfs4_client *nfs4_find_client(struct in_addr *addr)
 158 {
 159         struct nfs4_client *clp;
 160         spin_lock(&state_spinlock);
 161         clp = __nfs4_find_client(addr);
 162         spin_unlock(&state_spinlock);
 163         return clp;
 164 }
 165
 166 struct nfs4_client *
 167 nfs4_get_client(struct in_addr *addr)
 168 {
 169         struct nfs4_client *clp, *new = NULL;
 170
 171         spin_lock(&state_spinlock);
 172         for (;;) {
 173                 clp = __nfs4_find_client(addr);
 174                 if (clp != NULL)
 175                         break;
 176                 clp = new;
 177                 if (clp != NULL) {
 178                         list_add(&clp->cl_servers, &nfs4_clientid_list);
 179                         new = NULL;
 180                         break;
 181                 }
 182                 spin_unlock(&state_spinlock);
 183                 new = nfs4_alloc_client(addr);
 184                 spin_lock(&state_spinlock);
 185                 if (new == NULL)
 186                         break;
 187         }
 188         spin_unlock(&state_spinlock);
 189         if (new)
 190                 nfs4_free_client(new);
 191         return clp;
 192 }
 193
 194 void
 195 nfs4_put_client(struct nfs4_client *clp)
 196 {
 197         if (!atomic_dec_and_lock(&clp->cl_count, &state_spinlock))
 198                 return;
 199         list_del(&clp->cl_servers);
 200         spin_unlock(&state_spinlock);
 201         BUG_ON(!list_empty(&clp->cl_superblocks));
 202         wake_up_all(&clp->cl_waitq);
 203         rpc_wake_up(&clp->cl_rpcwaitq);
 204         nfs4_kill_renewd(clp);
 205         nfs4_free_client(clp);
 206 }
 207
 208 int nfs4_init_client(struct nfs4_client *clp)
 209 {
 210         int status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, nfs_callback_tcpport);
 211         if (status == 0)
 212                 status = nfs4_proc_setclientid_confirm(clp);
 213         if (status == 0)
 214                 nfs4_schedule_state_renewal(clp);
 215         return status;
 216 }
 217
 218 u32
 219 nfs4_alloc_lockowner_id(struct nfs4_client *clp)
 220 {
 221         return clp->cl_lockowner_id ++;
 222 }
 223
 224 static struct nfs4_state_owner *
 225 nfs4_client_grab_unused(struct nfs4_client *clp, struct rpc_cred *cred)
 226 {
 227         struct nfs4_state_owner *sp = NULL;
 228
 229         if (!list_empty(&clp->cl_unused)) {
 230                 sp = list_entry(clp->cl_unused.next, struct nfs4_state_owner, so_list);
 231                 atomic_inc(&sp->so_count);
 232                 sp->so_cred = cred;
 233                 list_move(&sp->so_list, &clp->cl_state_owners);
 234                 clp->cl_nunused--;
 235         }
 236         return sp;
 237 }
 238
 239 static struct nfs4_state_owner *
 240 nfs4_find_state_owner(struct nfs4_client *clp, struct rpc_cred *cred)
 241 {
 242         struct nfs4_state_owner *sp, *res = NULL;
 243
 244         list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
 245                 if (sp->so_cred != cred)
 246                         continue;
 247                 atomic_inc(&sp->so_count);
 248                 /* Move to the head of the list */
 249                 list_move(&sp->so_list, &clp->cl_state_owners);
 250                 res = sp;
 251                 break;
 252         }
 253         return res;
 254 }
 255
 256 /*
 257  * nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
 258  * create a new state_owner.
 259  *
 260  */
 261 static struct nfs4_state_owner *
 262 nfs4_alloc_state_owner(void)
 263 {
 264         struct nfs4_state_owner *sp;
 265
 266         sp = kmalloc(sizeof(*sp),GFP_KERNEL);
 267         if (!sp)
 268                 return NULL;
 269         init_MUTEX(&sp->so_sema);
 270         sp->so_seqid = 0;                 /* arbitrary */
 271         INIT_LIST_HEAD(&sp->so_states);
 272         INIT_LIST_HEAD(&sp->so_delegations);
 273         atomic_set(&sp->so_count, 1);
 274         return sp;
 275 }
 276
 277 static void
 278 nfs4_unhash_state_owner(struct nfs4_state_owner *sp)
 279 {
 280         struct nfs4_client *clp = sp->so_client;
 281         spin_lock(&clp->cl_lock);
 282         list_del_init(&sp->so_list);
 283         spin_unlock(&clp->cl_lock);
 284 }
 285
 286 /*
 287  * Note: must be called with clp->cl_sem held in order to prevent races
 288  *       with reboot recovery!
 289  */
 290 struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server, struct rpc_cred *cred)
 291 {
 292         struct nfs4_client *clp = server->nfs4_state;
 293         struct nfs4_state_owner *sp, *new;
 294
 295         get_rpccred(cred);
 296         new = nfs4_alloc_state_owner();
 297         spin_lock(&clp->cl_lock);
 298         sp = nfs4_find_state_owner(clp, cred);
 299         if (sp == NULL)
 300                 sp = nfs4_client_grab_unused(clp, cred);
 301         if (sp == NULL && new != NULL) {
 302                 list_add(&new->so_list, &clp->cl_state_owners);
 303                 new->so_client = clp;
 304                 new->so_id = nfs4_alloc_lockowner_id(clp);
 305                 new->so_cred = cred;
 306                 sp = new;
 307                 new = NULL;
 308         }
 309         spin_unlock(&clp->cl_lock);
 310         if (new)
 311                 kfree(new);
 312         if (sp != NULL)
 313                 return sp;
 314         put_rpccred(cred);
 315         return NULL;
 316 }
 317
 318 /*
 319  * Must be called with clp->cl_sem held in order to avoid races
 320  * with state recovery...
 321  */
 322 void nfs4_put_state_owner(struct nfs4_state_owner *sp)
 323 {
 324         struct nfs4_client *clp = sp->so_client;
 325         struct rpc_cred *cred = sp->so_cred;
 326
 327         if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
 328                 return;
 329         if (clp->cl_nunused >= OPENOWNER_POOL_SIZE)
 330                 goto out_free;
 331         if (list_empty(&sp->so_list))
 332                 goto out_free;
 333         list_move(&sp->so_list, &clp->cl_unused);
 334         clp->cl_nunused++;
 335         spin_unlock(&clp->cl_lock);
 336         put_rpccred(cred);
 337         cred = NULL;
 338         return;
 339 out_free:
 340         list_del(&sp->so_list);
 341         spin_unlock(&clp->cl_lock);
 342         put_rpccred(cred);
 343         kfree(sp);
 344 }
 345
 346 static struct nfs4_state *
 347 nfs4_alloc_open_state(void)
 348 {
 349         struct nfs4_state *state;
 350
 351         state = kmalloc(sizeof(*state), GFP_KERNEL);
 352         if (!state)
 353                 return NULL;
 354         state->state = 0;
 355         state->nreaders = 0;
 356         state->nwriters = 0;
 357         state->flags = 0;
 358         memset(state->stateid.data, 0, sizeof(state->stateid.data));
 359         atomic_set(&state->count, 1);
 360         INIT_LIST_HEAD(&state->lock_states);
 361         init_MUTEX(&state->lock_sema);
 362         rwlock_init(&state->state_lock);
 363         return state;
 364 }
 365
 366 static struct nfs4_state *
 367 __nfs4_find_state(struct inode *inode, struct rpc_cred *cred, mode_t mode)
 368 {
 369         struct nfs_inode *nfsi = NFS_I(inode);
 370         struct nfs4_state *state;
 371
 372         mode &= (FMODE_READ|FMODE_WRITE);
 373         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 374                 if (state->owner->so_cred != cred)
 375                         continue;
 376                 if ((mode & FMODE_READ) != 0 && state->nreaders == 0)
 377                         continue;
 378                 if ((mode & FMODE_WRITE) != 0 && state->nwriters == 0)
 379                         continue;
 380                 if ((state->state & mode) != mode)
 381                         continue;
 382                 atomic_inc(&state->count);
 383                 if (mode & FMODE_READ)
 384                         state->nreaders++;
 385                 if (mode & FMODE_WRITE)
 386                         state->nwriters++;
 387                 return state;
 388         }
 389         return NULL;
 390 }
 391
 392 static struct nfs4_state *
 393 __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 394 {
 395         struct nfs_inode *nfsi = NFS_I(inode);
 396         struct nfs4_state *state;
 397
 398         list_for_each_entry(state, &nfsi->open_states, inode_states) {
 399                 /* Is this in the process of being freed? */
 400                 if (state->nreaders == 0 && state->nwriters == 0)
 401                         continue;
 402                 if (state->owner == owner) {
 403                         atomic_inc(&state->count);
 404                         return state;
 405                 }
 406         }
 407         return NULL;
 408 }
 409
 410 struct nfs4_state *
 411 nfs4_find_state(struct inode *inode, struct rpc_cred *cred, mode_t mode)
 412 {
 413         struct nfs4_state *state;
 414
 415         spin_lock(&inode->i_lock);
 416         state = __nfs4_find_state(inode, cred, mode);
 417         spin_unlock(&inode->i_lock);
 418         return state;
 419 }
 420
 421 static void
 422 nfs4_free_open_state(struct nfs4_state *state)
 423 {
 424         kfree(state);
 425 }
 426
 427 struct nfs4_state *
 428 nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
 429 {
 430         struct nfs4_state *state, *new;
 431         struct nfs_inode *nfsi = NFS_I(inode);
 432
 433         spin_lock(&inode->i_lock);
 434         state = __nfs4_find_state_byowner(inode, owner);
 435         spin_unlock(&inode->i_lock);
 436         if (state)
 437                 goto out;
 438         new = nfs4_alloc_open_state();
 439         spin_lock(&inode->i_lock);
 440         state = __nfs4_find_state_byowner(inode, owner);
 441         if (state == NULL && new != NULL) {
 442                 state = new;
 443                 /* Caller *must* be holding owner->so_sem */
 444                 list_add(&state->open_states, &owner->so_states);
 445                 state->owner = owner;
 446                 atomic_inc(&owner->so_count);
 447                 list_add(&state->inode_states, &nfsi->open_states);
 448                 state->inode = inode;
 449                 spin_unlock(&inode->i_lock);
 450         } else {
 451                 spin_unlock(&inode->i_lock);
 452                 if (new)
 453                         nfs4_free_open_state(new);
 454         }
 455 out:
 456         return state;
 457 }
 458
 459 /*
 460  * Beware! Caller must be holding exactly one
 461  * reference to clp->cl_sem and owner->so_sema!
 462  */
 463 void nfs4_put_open_state(struct nfs4_state *state)
 464 {
 465         struct inode *inode = state->inode;
 466         struct nfs4_state_owner *owner = state->owner;
 467
 468         if (!atomic_dec_and_lock(&state->count, &inode->i_lock))
 469                 return;
 470         if (!list_empty(&state->inode_states))
 471                 list_del(&state->inode_states);
 472         spin_unlock(&inode->i_lock);
 473         list_del(&state->open_states);
 474         BUG_ON (state->state != 0);
 475         nfs4_free_open_state(state);
 476         nfs4_put_state_owner(owner);
 477 }
 478
 479 /*
 480  * Beware! Caller must be holding no references to clp->cl_sem!
 481  * of owner->so_sema!
 482  */
 483 void nfs4_close_state(struct nfs4_state *state, mode_t mode)
 484 {
 485         struct inode *inode = state->inode;
 486         struct nfs4_state_owner *owner = state->owner;
 487         struct nfs4_client *clp = owner->so_client;
 488         int newstate;
 489         int status = 0;
 490
 491         atomic_inc(&owner->so_count);
 492         down_read(&clp->cl_sem);
 493         down(&owner->so_sema);
 494         /* Protect against nfs4_find_state() */
 495         spin_lock(&inode->i_lock);
 496         if (mode & FMODE_READ)
 497                 state->nreaders--;
 498         if (mode & FMODE_WRITE)
 499                 state->nwriters--;
 500         if (state->nwriters == 0 && state->nreaders == 0)
 501                 list_del_init(&state->inode_states);
 502         spin_unlock(&inode->i_lock);
 503         newstate = 0;
 504         if (state->state != 0) {
 505                 if (state->nreaders)
 506                         newstate |= FMODE_READ;
 507                 if (state->nwriters)
 508                         newstate |= FMODE_WRITE;
 509                 if (state->state == newstate)
 510                         goto out;
 511                 if (newstate != 0)
 512                         status = nfs4_do_downgrade(inode, state, newstate);
 513                 else
 514                         status = nfs4_do_close(inode, state);
 515         }
 516 out:
 517         nfs4_put_open_state(state);
 518         up(&owner->so_sema);
 519         nfs4_put_state_owner(owner);
 520         up_read(&clp->cl_sem);
 521 }
 522
 523 /*
 524  * Search the state->lock_states for an existing lock_owner
 525  * that is compatible with current->files
 526  */
 527 static struct nfs4_lock_state *
 528 __nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 529 {
 530         struct nfs4_lock_state *pos;
 531         list_for_each_entry(pos, &state->lock_states, ls_locks) {
 532                 if (pos->ls_owner != fl_owner)
 533                         continue;
 534                 atomic_inc(&pos->ls_count);
 535                 return pos;
 536         }
 537         return NULL;
 538 }
 539
 540 struct nfs4_lock_state *
 541 nfs4_find_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 542 {
 543         struct nfs4_lock_state *lsp;
 544         read_lock(&state->state_lock);
 545         lsp = __nfs4_find_lock_state(state, fl_owner);
 546         read_unlock(&state->state_lock);
 547         return lsp;
 548 }
 549
 550 /*
 551  * Return a compatible lock_state. If no initialized lock_state structure
 552  * exists, return an uninitialized one.
 553  *
 554  * The caller must be holding state->lock_sema
 555  */
 556 static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t fl_owner)
 557 {
 558         struct nfs4_lock_state *lsp;
 559         struct nfs4_client *clp = state->owner->so_client;
 560
 561         lsp = kmalloc(sizeof(*lsp), GFP_KERNEL);
 562         if (lsp == NULL)
 563                 return NULL;
 564         lsp->ls_flags = 0;
 565         lsp->ls_seqid = 0;      /* arbitrary */
 566         lsp->ls_id = -1;
 567         memset(lsp->ls_stateid.data, 0, sizeof(lsp->ls_stateid.data));
 568         atomic_set(&lsp->ls_count, 1);
 569         lsp->ls_owner = fl_owner;
 570         INIT_LIST_HEAD(&lsp->ls_locks);
 571         spin_lock(&clp->cl_lock);
 572         lsp->ls_id = nfs4_alloc_lockowner_id(clp);
 573         spin_unlock(&clp->cl_lock);
 574         return lsp;
 575 }
 576
 577 /*
 578  * Return a compatible lock_state. If no initialized lock_state structure
 579  * exists, return an uninitialized one.
 580  *
 581  * The caller must be holding state->lock_sema and clp->cl_sem
 582  */
 583 struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
 584 {
 585         struct nfs4_lock_state * lsp;
 586
 587         lsp = nfs4_find_lock_state(state, owner);
 588         if (lsp == NULL)
 589                 lsp = nfs4_alloc_lock_state(state, owner);
 590         return lsp;
 591 }
 592
 593 /*
 594  * Byte-range lock aware utility to initialize the stateid of read/write
 595  * requests.
 596  */
 597 void
 598 nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t fl_owner)
 599 {
 600         if (test_bit(LK_STATE_IN_USE, &state->flags)) {
 601                 struct nfs4_lock_state *lsp;
 602
 603                 lsp = nfs4_find_lock_state(state, fl_owner);
 604                 if (lsp) {
 605                         memcpy(dst, &lsp->ls_stateid, sizeof(*dst));
 606                         nfs4_put_lock_state(lsp);
 607                         return;
 608                 }
 609         }
 610         memcpy(dst, &state->stateid, sizeof(*dst));
 611 }
 612
 613 /*
 614 * Called with state->lock_sema and clp->cl_sem held.
 615 */
 616 void nfs4_increment_lock_seqid(int status, struct nfs4_lock_state *lsp)
 617 {
 618         if (status == NFS_OK || seqid_mutating_err(-status))
 619                 lsp->ls_seqid++;
 620 }
 621
 622 /*
 623 * Check to see if the request lock (type FL_UNLK) effects the fl lock.
 624 *
 625 * fl and request must have the same posix owner
 626 *
 627 * return:
 628 * 0 -> fl not effected by request
 629 * 1 -> fl consumed by request
 630 */
 631
 632 static int
 633 nfs4_check_unlock(struct file_lock *fl, struct file_lock *request)
 634 {
 635         if (fl->fl_start >= request->fl_start && fl->fl_end <= request->fl_end)
 636                 return 1;
 637         return 0;
 638 }
 639
 640 /*
 641  * Post an initialized lock_state on the state->lock_states list.
 642  */
 643 void nfs4_notify_setlk(struct nfs4_state *state, struct file_lock *request, struct nfs4_lock_state *lsp)
 644 {
 645         if (!list_empty(&lsp->ls_locks))
 646                 return;
 647         atomic_inc(&lsp->ls_count);
 648         write_lock(&state->state_lock);
 649         list_add(&lsp->ls_locks, &state->lock_states);
 650         set_bit(LK_STATE_IN_USE, &state->flags);
 651         write_unlock(&state->state_lock);
 652 }
 653
 654 /*
 655  * to decide to 'reap' lock state:
 656  * 1) search i_flock for file_locks with fl.lock_state = to ls.
 657  * 2) determine if unlock will consume found lock.
 658  *      if so, reap
 659  *
 660  *      else, don't reap.
 661  *
 662  */
 663 void
 664 nfs4_notify_unlck(struct nfs4_state *state, struct file_lock *request, struct nfs4_lock_state *lsp)
 665 {
 666         struct inode *inode = state->inode;
 667         struct file_lock *fl;
 668
 669         for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 670                 if (!(fl->fl_flags & FL_POSIX))
 671                         continue;
 672                 if (fl->fl_owner != lsp->ls_owner)
 673                         continue;
 674                 /* Exit if we find at least one lock which is not consumed */
 675                 if (nfs4_check_unlock(fl,request) == 0)
 676                         return;
 677         }
 678
 679         write_lock(&state->state_lock);
 680         list_del_init(&lsp->ls_locks);
 681         if (list_empty(&state->lock_states))
 682                 clear_bit(LK_STATE_IN_USE, &state->flags);
 683         write_unlock(&state->state_lock);
 684         nfs4_put_lock_state(lsp);
 685 }
 686
 687 /*
 688  * Release reference to lock_state, and free it if we see that
 689  * it is no longer in use
 690  */
 691 void
 692 nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 693 {
 694         if (!atomic_dec_and_test(&lsp->ls_count))
 695                 return;
 696         BUG_ON (!list_empty(&lsp->ls_locks));
 697         kfree(lsp);
 698 }
 699
 700 /*
 701 * Called with sp->so_sema and clp->cl_sem held.
 702 *
 703 * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
 704 * failed with a seqid incrementing error -
 705 * see comments nfs_fs.h:seqid_mutating_error()
 706 */
 707 void nfs4_increment_seqid(int status, struct nfs4_state_owner *sp)
 708 {
 709         if (status == NFS_OK || seqid_mutating_err(-status))
 710                 sp->so_seqid++;
 711         /* If the server returns BAD_SEQID, unhash state_owner here */
 712         if (status == -NFS4ERR_BAD_SEQID)
 713                 nfs4_unhash_state_owner(sp);
 714 }
 715
 716 static int reclaimer(void *);
 717 struct reclaimer_args {
 718         struct nfs4_client *clp;
 719         struct completion complete;
 720 };
 721
 722 /*
 723  * State recovery routine
 724  */
 725 void
 726 nfs4_recover_state(void *data)
 727 {
 728         struct nfs4_client *clp = (struct nfs4_client *)data;
 729         struct reclaimer_args args = {
 730                 .clp = clp,
 731         };
 732         might_sleep();
 733
 734         init_completion(&args.complete);
 735
 736         if (kernel_thread(reclaimer, &args, CLONE_KERNEL) < 0)
 737                 goto out_failed_clear;
 738         wait_for_completion(&args.complete);
 739         return;
 740 out_failed_clear:
 741         set_bit(NFS4CLNT_OK, &clp->cl_state);
 742         wake_up_all(&clp->cl_waitq);
 743         rpc_wake_up(&clp->cl_rpcwaitq);
 744 }
 745
 746 /*
 747  * Schedule a state recovery attempt
 748  */
 749 void
 750 nfs4_schedule_state_recovery(struct nfs4_client *clp)
 751 {
 752         if (!clp)
 753                 return;
 754         if (test_and_clear_bit(NFS4CLNT_OK, &clp->cl_state))
 755                 schedule_work(&clp->cl_recoverd);
 756 }
 757
 758 static int nfs4_reclaim_locks(struct nfs4_state *state)
 759 {
 760         struct inode *inode = state->inode;
 761         struct file_lock *fl;
 762         int status = 0;
 763
 764         for (fl = inode->i_flock; fl != 0; fl = fl->fl_next) {
 765                 if (!(fl->fl_flags & FL_POSIX))
 766                         continue;
 767                 if (((struct nfs_open_context *)fl->fl_file->private_data)->state != state)
 768                         continue;
 769                 status = nfs4_lock_reclaim(state, fl);
 770                 if (status >= 0)
 771                         continue;
 772                 switch (status) {
 773                         default:
 774                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 775                                                 __FUNCTION__, status);
 776                         case -NFS4ERR_EXPIRED:
 777                         case -NFS4ERR_NO_GRACE:
 778                         case -NFS4ERR_RECLAIM_BAD:
 779                         case -NFS4ERR_RECLAIM_CONFLICT:
 780                                 /* kill_proc(fl->fl_owner, SIGLOST, 1); */
 781                                 break;
 782                         case -NFS4ERR_STALE_CLIENTID:
 783                                 goto out_err;
 784                 }
 785         }
 786         return 0;
 787 out_err:
 788         return status;
 789 }
 790
 791 static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp)
 792 {
 793         struct nfs4_state *state;
 794         struct nfs4_lock_state *lock;
 795         int status = 0;
 796
 797         list_for_each_entry(state, &sp->so_states, open_states) {
 798                 if (state->state == 0)
 799                         continue;
 800                 status = nfs4_open_reclaim(sp, state);
 801                 list_for_each_entry(lock, &state->lock_states, ls_locks)
 802                         lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
 803                 if (status >= 0) {
 804                         status = nfs4_reclaim_locks(state);
 805                         if (status < 0)
 806                                 goto out_err;
 807                         list_for_each_entry(lock, &state->lock_states, ls_locks) {
 808                                 if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
 809                                         printk("%s: Lock reclaim failed!\n",
 810                                                         __FUNCTION__);
 811                         }
 812                         continue;
 813                 }
 814                 switch (status) {
 815                         default:
 816                                 printk(KERN_ERR "%s: unhandled error %d. Zeroing state\n",
 817                                                 __FUNCTION__, status);
 818                         case -NFS4ERR_EXPIRED:
 819                         case -NFS4ERR_NO_GRACE:
 820                         case -NFS4ERR_RECLAIM_BAD:
 821                         case -NFS4ERR_RECLAIM_CONFLICT:
 822                                 /*
 823                                  * Open state on this file cannot be recovered
 824                                  * All we can do is revert to using the zero stateid.
 825                                  */
 826                                 memset(state->stateid.data, 0,
 827                                         sizeof(state->stateid.data));
 828                                 /* Mark the file as being 'closed' */
 829                                 state->state = 0;
 830                                 break;
 831                         case -NFS4ERR_STALE_CLIENTID:
 832                                 goto out_err;
 833                 }
 834         }
 835         return 0;
 836 out_err:
 837         return status;
 838 }
 839
 840 static int reclaimer(void *ptr)
 841 {
 842         struct reclaimer_args *args = (struct reclaimer_args *)ptr;
 843         struct nfs4_client *clp = args->clp;
 844         struct nfs4_state_owner *sp;
 845         int status = 0;
 846
 847         daemonize("%u.%u.%u.%u-reclaim", NIPQUAD(clp->cl_addr));
 848         allow_signal(SIGKILL);
 849
 850         atomic_inc(&clp->cl_count);
 851         complete(&args->complete);
 852
 853         /* Ensure exclusive access to NFSv4 state */
 854         lock_kernel();
 855         down_write(&clp->cl_sem);
 856         /* Are there any NFS mounts out there? */
 857         if (list_empty(&clp->cl_superblocks))
 858                 goto out;
 859 restart_loop:
 860         status = nfs4_proc_renew(clp);
 861         if (status == 0 || status == -NFS4ERR_CB_PATH_DOWN)
 862                 goto out;
 863         status = nfs4_init_client(clp);
 864         if (status)
 865                 goto out_error;
 866         /* Mark all delagations for reclaim */
 867         nfs_delegation_mark_reclaim(clp);
 868         /* Note: list is protected by exclusive lock on cl->cl_sem */
 869         list_for_each_entry(sp, &clp->cl_state_owners, so_list) {
 870                 status = nfs4_reclaim_open_state(sp);
 871                 if (status < 0) {
 872                         if (status == -NFS4ERR_STALE_CLIENTID)
 873                                 goto restart_loop;
 874                         goto out_error;
 875                 }
 876         }
 877         nfs_delegation_reap_unclaimed(clp);
 878 out:
 879         set_bit(NFS4CLNT_OK, &clp->cl_state);
 880         up_write(&clp->cl_sem);
 881         unlock_kernel();
 882         wake_up_all(&clp->cl_waitq);
 883         rpc_wake_up(&clp->cl_rpcwaitq);
 884         if (status == -NFS4ERR_CB_PATH_DOWN)
 885                 nfs_handle_cb_pathdown(clp);
 886         nfs4_put_client(clp);
 887         return 0;
 888 out_error:
 889         printk(KERN_WARNING "Error: state recovery failed on NFSv4 server %u.%u.%u.%u with error %d\n",
 890                                 NIPQUAD(clp->cl_addr.s_addr), -status);
 891         goto out;
 892 }
 893
 894 /*
 895  * Local variables:
 896  *  c-basic-offset: 8
 897  * End:
 898  */