fs/nfs/pnfs.c

   1 /*
   2  *  pNFS functions to call and manage layout drivers.
   3  *
   4  *  Copyright (c) 2002 [year of first publication]
   5  *  The Regents of the University of Michigan
   6  *  All Rights Reserved
   7  *
   8  *  Dean Hildebrand <dhildebz@umich.edu>
   9  *
  10  *  Permission is granted to use, copy, create derivative works, and
  11  *  redistribute this software and such derivative works for any purpose,
  12  *  so long as the name of the University of Michigan is not used in
  13  *  any advertising or publicity pertaining to the use or distribution
  14  *  of this software without specific, written prior authorization. If
  15  *  the above copyright notice or any other identification of the
  16  *  University of Michigan is included in any copy of any portion of
  17  *  this software, then the disclaimer below must also be included.
  18  *
  19  *  This software is provided as is, without representation or warranty
  20  *  of any kind either express or implied, including without limitation
  21  *  the implied warranties of merchantability, fitness for a particular
  22  *  purpose, or noninfringement.  The Regents of the University of
  23  *  Michigan shall not be liable for any damages, including special,
  24  *  indirect, incidental, or consequential damages, with respect to any
  25  *  claim arising out of or in connection with the use of the software,
  26  *  even if it has been or is hereafter advised of the possibility of
  27  *  such damages.
  28  */
  29
  30 #include <linux/nfs_fs.h>
  31 #include <linux/nfs_page.h>
  32 #include <linux/module.h>
  33 #include "internal.h"
  34 #include "pnfs.h"
  35 #include "iostat.h"
  36
  37 #define NFSDBG_FACILITY         NFSDBG_PNFS
  38 #define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
  39
  40 /* Locking:
  41  *
  42  * pnfs_spinlock:
  43  *      protects pnfs_modules_tbl.
  44  */
  45 static DEFINE_SPINLOCK(pnfs_spinlock);
  46
  47 /*
  48  * pnfs_modules_tbl holds all pnfs modules
  49  */
  50 static LIST_HEAD(pnfs_modules_tbl);
  51
  52 /* Return the registered pnfs layout driver module matching given id */
  53 static struct pnfs_layoutdriver_type *
  54 find_pnfs_driver_locked(u32 id)
  55 {
  56         struct pnfs_layoutdriver_type *local;
  57
  58         list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
  59                 if (local->id == id)
  60                         goto out;
  61         local = NULL;
  62 out:
  63         dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
  64         return local;
  65 }
  66
  67 static struct pnfs_layoutdriver_type *
  68 find_pnfs_driver(u32 id)
  69 {
  70         struct pnfs_layoutdriver_type *local;
  71
  72         spin_lock(&pnfs_spinlock);
  73         local = find_pnfs_driver_locked(id);
  74         if (local != NULL && !try_module_get(local->owner)) {
  75                 dprintk("%s: Could not grab reference on module\n", __func__);
  76                 local = NULL;
  77         }
  78         spin_unlock(&pnfs_spinlock);
  79         return local;
  80 }
  81
  82 void
  83 unset_pnfs_layoutdriver(struct nfs_server *nfss)
  84 {
  85         if (nfss->pnfs_curr_ld) {
  86                 if (nfss->pnfs_curr_ld->clear_layoutdriver)
  87                         nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
  88                 /* Decrement the MDS count. Purge the deviceid cache if zero */
  89                 if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
  90                         nfs4_deviceid_purge_client(nfss->nfs_client);
  91                 module_put(nfss->pnfs_curr_ld->owner);
  92         }
  93         nfss->pnfs_curr_ld = NULL;
  94 }
  95
  96 /*
  97  * Try to set the server's pnfs module to the pnfs layout type specified by id.
  98  * Currently only one pNFS layout driver per filesystem is supported.
  99  *
 100  * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
 101  */
 102 void
 103 set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
 104                       u32 id)
 105 {
 106         struct pnfs_layoutdriver_type *ld_type = NULL;
 107
 108         if (id == 0)
 109                 goto out_no_driver;
 110         if (!(server->nfs_client->cl_exchange_flags &
 111                  (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
 112                 printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
 113                         __func__, id, server->nfs_client->cl_exchange_flags);
 114                 goto out_no_driver;
 115         }
 116         ld_type = find_pnfs_driver(id);
 117         if (!ld_type) {
 118                 request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
 119                 ld_type = find_pnfs_driver(id);
 120                 if (!ld_type) {
 121                         dprintk("%s: No pNFS module found for %u.\n",
 122                                 __func__, id);
 123                         goto out_no_driver;
 124                 }
 125         }
 126         server->pnfs_curr_ld = ld_type;
 127         if (ld_type->set_layoutdriver
 128             && ld_type->set_layoutdriver(server, mntfh)) {
 129                 printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
 130                         "driver %u.\n", __func__, id);
 131                 module_put(ld_type->owner);
 132                 goto out_no_driver;
 133         }
 134         /* Bump the MDS count */
 135         atomic_inc(&server->nfs_client->cl_mds_count);
 136
 137         dprintk("%s: pNFS module for %u set\n", __func__, id);
 138         return;
 139
 140 out_no_driver:
 141         dprintk("%s: Using NFSv4 I/O\n", __func__);
 142         server->pnfs_curr_ld = NULL;
 143 }
 144
 145 int
 146 pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 147 {
 148         int status = -EINVAL;
 149         struct pnfs_layoutdriver_type *tmp;
 150
 151         if (ld_type->id == 0) {
 152                 printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
 153                 return status;
 154         }
 155         if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
 156                 printk(KERN_ERR "NFS: %s Layout driver must provide "
 157                        "alloc_lseg and free_lseg.\n", __func__);
 158                 return status;
 159         }
 160
 161         spin_lock(&pnfs_spinlock);
 162         tmp = find_pnfs_driver_locked(ld_type->id);
 163         if (!tmp) {
 164                 list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
 165                 status = 0;
 166                 dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
 167                         ld_type->name);
 168         } else {
 169                 printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
 170                         __func__, ld_type->id);
 171         }
 172         spin_unlock(&pnfs_spinlock);
 173
 174         return status;
 175 }
 176 EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
 177
 178 void
 179 pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
 180 {
 181         dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
 182         spin_lock(&pnfs_spinlock);
 183         list_del(&ld_type->pnfs_tblid);
 184         spin_unlock(&pnfs_spinlock);
 185 }
 186 EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
 187
 188 /*
 189  * pNFS client layout cache
 190  */
 191
 192 /* Need to hold i_lock if caller does not already hold reference */
 193 void
 194 pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo)
 195 {
 196         atomic_inc(&lo->plh_refcount);
 197 }
 198
 199 static struct pnfs_layout_hdr *
 200 pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
 201 {
 202         struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
 203         return ld->alloc_layout_hdr ? ld->alloc_layout_hdr(ino, gfp_flags) :
 204                 kzalloc(sizeof(struct pnfs_layout_hdr), gfp_flags);
 205 }
 206
 207 static void
 208 pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
 209 {
 210         struct pnfs_layoutdriver_type *ld = NFS_SERVER(lo->plh_inode)->pnfs_curr_ld;
 211         put_rpccred(lo->plh_lc_cred);
 212         return ld->alloc_layout_hdr ? ld->free_layout_hdr(lo) : kfree(lo);
 213 }
 214
 215 static void
 216 destroy_layout_hdr(struct pnfs_layout_hdr *lo)
 217 {
 218         struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
 219         dprintk("%s: freeing layout cache %p\n", __func__, lo);
 220         BUG_ON(!list_empty(&lo->plh_layouts));
 221         nfsi->layout = NULL;
 222         /* Reset MDS Threshold I/O counters */
 223         nfsi->write_io = 0;
 224         nfsi->read_io = 0;
 225         pnfs_free_layout_hdr(lo);
 226 }
 227
 228 static void
 229 pnfs_put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
 230 {
 231         if (atomic_dec_and_test(&lo->plh_refcount))
 232                 destroy_layout_hdr(lo);
 233 }
 234
 235 void
 236 pnfs_put_layout_hdr(struct pnfs_layout_hdr *lo)
 237 {
 238         struct inode *inode = lo->plh_inode;
 239
 240         if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
 241                 destroy_layout_hdr(lo);
 242                 spin_unlock(&inode->i_lock);
 243         }
 244 }
 245
 246 static int
 247 pnfs_iomode_to_fail_bit(u32 iomode)
 248 {
 249         return iomode == IOMODE_RW ?
 250                 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
 251 }
 252
 253 static void
 254 pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 255 {
 256         lo->plh_retry_timestamp = jiffies;
 257         if (test_and_set_bit(fail_bit, &lo->plh_flags))
 258                 atomic_inc(&lo->plh_refcount);
 259 }
 260
 261 static void
 262 pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
 263 {
 264         if (test_and_clear_bit(fail_bit, &lo->plh_flags))
 265                 atomic_dec(&lo->plh_refcount);
 266 }
 267
 268 static void
 269 pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 270 {
 271         struct inode *inode = lo->plh_inode;
 272         struct pnfs_layout_range range = {
 273                 .iomode = iomode,
 274                 .offset = 0,
 275                 .length = NFS4_MAX_UINT64,
 276         };
 277         LIST_HEAD(head);
 278
 279         spin_lock(&inode->i_lock);
 280         pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
 281         pnfs_mark_matching_lsegs_invalid(lo, &head, &range);
 282         spin_unlock(&inode->i_lock);
 283         pnfs_free_lseg_list(&head);
 284         dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
 285                         iomode == IOMODE_RW ?  "RW" : "READ");
 286 }
 287
 288 static bool
 289 pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
 290 {
 291         unsigned long start, end;
 292         int fail_bit = pnfs_iomode_to_fail_bit(iomode);
 293
 294         if (test_bit(fail_bit, &lo->plh_flags) == 0)
 295                 return false;
 296         end = jiffies;
 297         start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
 298         if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
 299                 /* It is time to retry the failed layoutgets */
 300                 pnfs_layout_clear_fail_bit(lo, fail_bit);
 301                 return false;
 302         }
 303         return true;
 304 }
 305
 306 static void
 307 init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
 308 {
 309         INIT_LIST_HEAD(&lseg->pls_list);
 310         INIT_LIST_HEAD(&lseg->pls_lc_list);
 311         atomic_set(&lseg->pls_refcount, 1);
 312         smp_mb();
 313         set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
 314         lseg->pls_layout = lo;
 315 }
 316
 317 static void free_lseg(struct pnfs_layout_segment *lseg)
 318 {
 319         struct inode *ino = lseg->pls_layout->plh_inode;
 320
 321         NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
 322         /* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
 323         pnfs_put_layout_hdr(NFS_I(ino)->layout);
 324 }
 325
 326 static void
 327 pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
 328                 struct pnfs_layout_segment *lseg)
 329 {
 330         struct inode *inode = lo->plh_inode;
 331
 332         WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 333         list_del_init(&lseg->pls_list);
 334         if (list_empty(&lo->plh_segs)) {
 335                 set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags);
 336                 /* Matched by initial refcount set in alloc_init_layout_hdr */
 337                 pnfs_put_layout_hdr_locked(lo);
 338         }
 339         rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
 340 }
 341
 342 void
 343 pnfs_put_lseg(struct pnfs_layout_segment *lseg)
 344 {
 345         struct pnfs_layout_hdr *lo;
 346         struct inode *inode;
 347
 348         if (!lseg)
 349                 return;
 350
 351         dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
 352                 atomic_read(&lseg->pls_refcount),
 353                 test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
 354         lo = lseg->pls_layout;
 355         inode = lo->plh_inode;
 356         if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
 357                 LIST_HEAD(free_me);
 358
 359                 pnfs_layout_remove_lseg(lo, lseg);
 360                 spin_unlock(&inode->i_lock);
 361                 list_add(&lseg->pls_list, &free_me);
 362                 pnfs_free_lseg_list(&free_me);
 363         }
 364 }
 365 EXPORT_SYMBOL_GPL(pnfs_put_lseg);
 366
 367 static inline u64
 368 end_offset(u64 start, u64 len)
 369 {
 370         u64 end;
 371
 372         end = start + len;
 373         return end >= start ? end : NFS4_MAX_UINT64;
 374 }
 375
 376 /* last octet in a range */
 377 static inline u64
 378 last_byte_offset(u64 start, u64 len)
 379 {
 380         u64 end;
 381
 382         BUG_ON(!len);
 383         end = start + len;
 384         return end > start ? end - 1 : NFS4_MAX_UINT64;
 385 }
 386
 387 /*
 388  * is l2 fully contained in l1?
 389  *   start1                             end1
 390  *   [----------------------------------)
 391  *           start2           end2
 392  *           [----------------)
 393  */
 394 static inline int
 395 lo_seg_contained(struct pnfs_layout_range *l1,
 396                  struct pnfs_layout_range *l2)
 397 {
 398         u64 start1 = l1->offset;
 399         u64 end1 = end_offset(start1, l1->length);
 400         u64 start2 = l2->offset;
 401         u64 end2 = end_offset(start2, l2->length);
 402
 403         return (start1 <= start2) && (end1 >= end2);
 404 }
 405
 406 /*
 407  * is l1 and l2 intersecting?
 408  *   start1                             end1
 409  *   [----------------------------------)
 410  *                              start2           end2
 411  *                              [----------------)
 412  */
 413 static inline int
 414 lo_seg_intersecting(struct pnfs_layout_range *l1,
 415                     struct pnfs_layout_range *l2)
 416 {
 417         u64 start1 = l1->offset;
 418         u64 end1 = end_offset(start1, l1->length);
 419         u64 start2 = l2->offset;
 420         u64 end2 = end_offset(start2, l2->length);
 421
 422         return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
 423                (end2 == NFS4_MAX_UINT64 || end2 > start1);
 424 }
 425
 426 static bool
 427 should_free_lseg(struct pnfs_layout_range *lseg_range,
 428                  struct pnfs_layout_range *recall_range)
 429 {
 430         return (recall_range->iomode == IOMODE_ANY ||
 431                 lseg_range->iomode == recall_range->iomode) &&
 432                lo_seg_intersecting(lseg_range, recall_range);
 433 }
 434
 435 /* Returns 1 if lseg is removed from list, 0 otherwise */
 436 static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
 437                              struct list_head *tmp_list)
 438 {
 439         int rv = 0;
 440
 441         if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
 442                 /* Remove the reference keeping the lseg in the
 443                  * list.  It will now be removed when all
 444                  * outstanding io is finished.
 445                  */
 446                 dprintk("%s: lseg %p ref %d\n", __func__, lseg,
 447                         atomic_read(&lseg->pls_refcount));
 448                 if (atomic_dec_and_test(&lseg->pls_refcount)) {
 449                         pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
 450                         list_add(&lseg->pls_list, tmp_list);
 451                         rv = 1;
 452                 }
 453         }
 454         return rv;
 455 }
 456
 457 /* Returns count of number of matching invalid lsegs remaining in list
 458  * after call.
 459  */
 460 int
 461 pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
 462                             struct list_head *tmp_list,
 463                             struct pnfs_layout_range *recall_range)
 464 {
 465         struct pnfs_layout_segment *lseg, *next;
 466         int invalid = 0, removed = 0;
 467
 468         dprintk("%s:Begin lo %p\n", __func__, lo);
 469
 470         if (list_empty(&lo->plh_segs)) {
 471                 if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
 472                         pnfs_put_layout_hdr_locked(lo);
 473                 return 0;
 474         }
 475         list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
 476                 if (!recall_range ||
 477                     should_free_lseg(&lseg->pls_range, recall_range)) {
 478                         dprintk("%s: freeing lseg %p iomode %d "
 479                                 "offset %llu length %llu\n", __func__,
 480                                 lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
 481                                 lseg->pls_range.length);
 482                         invalid++;
 483                         removed += mark_lseg_invalid(lseg, tmp_list);
 484                 }
 485         dprintk("%s:Return %i\n", __func__, invalid - removed);
 486         return invalid - removed;
 487 }
 488
 489 /* note free_me must contain lsegs from a single layout_hdr */
 490 void
 491 pnfs_free_lseg_list(struct list_head *free_me)
 492 {
 493         struct pnfs_layout_segment *lseg, *tmp;
 494         struct pnfs_layout_hdr *lo;
 495
 496         if (list_empty(free_me))
 497                 return;
 498
 499         lo = list_first_entry(free_me, struct pnfs_layout_segment,
 500                               pls_list)->pls_layout;
 501
 502         if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) {
 503                 struct nfs_client *clp;
 504
 505                 clp = NFS_SERVER(lo->plh_inode)->nfs_client;
 506                 spin_lock(&clp->cl_lock);
 507                 list_del_init(&lo->plh_layouts);
 508                 spin_unlock(&clp->cl_lock);
 509         }
 510         list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
 511                 list_del(&lseg->pls_list);
 512                 free_lseg(lseg);
 513         }
 514 }
 515
 516 void
 517 pnfs_destroy_layout(struct nfs_inode *nfsi)
 518 {
 519         struct pnfs_layout_hdr *lo;
 520         LIST_HEAD(tmp_list);
 521
 522         spin_lock(&nfsi->vfs_inode.i_lock);
 523         lo = nfsi->layout;
 524         if (lo) {
 525                 lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
 526                 pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
 527                 pnfs_get_layout_hdr(lo);
 528                 pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
 529                 pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
 530                 spin_unlock(&nfsi->vfs_inode.i_lock);
 531                 pnfs_free_lseg_list(&tmp_list);
 532                 pnfs_put_layout_hdr(lo);
 533         } else
 534                 spin_unlock(&nfsi->vfs_inode.i_lock);
 535 }
 536 EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
 537
 538 /*
 539  * Called by the state manger to remove all layouts established under an
 540  * expired lease.
 541  */
 542 void
 543 pnfs_destroy_all_layouts(struct nfs_client *clp)
 544 {
 545         struct nfs_server *server;
 546         struct pnfs_layout_hdr *lo;
 547         LIST_HEAD(tmp_list);
 548
 549         nfs4_deviceid_mark_client_invalid(clp);
 550         nfs4_deviceid_purge_client(clp);
 551
 552         spin_lock(&clp->cl_lock);
 553         rcu_read_lock();
 554         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 555                 if (!list_empty(&server->layouts))
 556                         list_splice_init(&server->layouts, &tmp_list);
 557         }
 558         rcu_read_unlock();
 559         spin_unlock(&clp->cl_lock);
 560
 561         while (!list_empty(&tmp_list)) {
 562                 lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,
 563                                 plh_layouts);
 564                 dprintk("%s freeing layout for inode %lu\n", __func__,
 565                         lo->plh_inode->i_ino);
 566                 list_del_init(&lo->plh_layouts);
 567                 pnfs_destroy_layout(NFS_I(lo->plh_inode));
 568         }
 569 }
 570
 571 /* update lo->plh_stateid with new if is more recent */
 572 void
 573 pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
 574                         bool update_barrier)
 575 {
 576         u32 oldseq, newseq;
 577
 578         oldseq = be32_to_cpu(lo->plh_stateid.seqid);
 579         newseq = be32_to_cpu(new->seqid);
 580         if ((int)(newseq - oldseq) > 0) {
 581                 nfs4_stateid_copy(&lo->plh_stateid, new);
 582                 if (update_barrier) {
 583                         u32 new_barrier = be32_to_cpu(new->seqid);
 584
 585                         if ((int)(new_barrier - lo->plh_barrier))
 586                                 lo->plh_barrier = new_barrier;
 587                 } else {
 588                         /* Because of wraparound, we want to keep the barrier
 589                          * "close" to the current seqids.  It needs to be
 590                          * within 2**31 to count as "behind", so if it
 591                          * gets too near that limit, give us a litle leeway
 592                          * and bring it to within 2**30.
 593                          * NOTE - and yes, this is all unsigned arithmetic.
 594                          */
 595                         if (unlikely((newseq - lo->plh_barrier) > (3 << 29)))
 596                                 lo->plh_barrier = newseq - (1 << 30);
 597                 }
 598         }
 599 }
 600
 601 /* lget is set to 1 if called from inside send_layoutget call chain */
 602 static bool
 603 pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
 604                         int lget)
 605 {
 606         if ((stateid) &&
 607             (int)(lo->plh_barrier - be32_to_cpu(stateid->seqid)) >= 0)
 608                 return true;
 609         return lo->plh_block_lgets ||
 610                 test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
 611                 test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
 612                 (list_empty(&lo->plh_segs) &&
 613                  (atomic_read(&lo->plh_outstanding) > lget));
 614 }
 615
 616 int
 617 pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
 618                               struct nfs4_state *open_state)
 619 {
 620         int status = 0;
 621
 622         dprintk("--> %s\n", __func__);
 623         spin_lock(&lo->plh_inode->i_lock);
 624         if (pnfs_layoutgets_blocked(lo, NULL, 1)) {
 625                 status = -EAGAIN;
 626         } else if (list_empty(&lo->plh_segs)) {
 627                 int seq;
 628
 629                 do {
 630                         seq = read_seqbegin(&open_state->seqlock);
 631                         nfs4_stateid_copy(dst, &open_state->stateid);
 632                 } while (read_seqretry(&open_state->seqlock, seq));
 633         } else
 634                 nfs4_stateid_copy(dst, &lo->plh_stateid);
 635         spin_unlock(&lo->plh_inode->i_lock);
 636         dprintk("<-- %s\n", __func__);
 637         return status;
 638 }
 639
 640 /*
 641 * Get layout from server.
 642 *    for now, assume that whole file layouts are requested.
 643 *    arg->offset: 0
 644 *    arg->length: all ones
 645 */
 646 static struct pnfs_layout_segment *
 647 send_layoutget(struct pnfs_layout_hdr *lo,
 648            struct nfs_open_context *ctx,
 649            struct pnfs_layout_range *range,
 650            gfp_t gfp_flags)
 651 {
 652         struct inode *ino = lo->plh_inode;
 653         struct nfs_server *server = NFS_SERVER(ino);
 654         struct nfs4_layoutget *lgp;
 655         struct pnfs_layout_segment *lseg;
 656
 657         dprintk("--> %s\n", __func__);
 658
 659         BUG_ON(ctx == NULL);
 660         lgp = kzalloc(sizeof(*lgp), gfp_flags);
 661         if (lgp == NULL)
 662                 return NULL;
 663
 664         lgp->args.minlength = PAGE_CACHE_SIZE;
 665         if (lgp->args.minlength > range->length)
 666                 lgp->args.minlength = range->length;
 667         lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
 668         lgp->args.range = *range;
 669         lgp->args.type = server->pnfs_curr_ld->id;
 670         lgp->args.inode = ino;
 671         lgp->args.ctx = get_nfs_open_context(ctx);
 672         lgp->gfp_flags = gfp_flags;
 673
 674         /* Synchronously retrieve layout information from server and
 675          * store in lseg.
 676          */
 677         lseg = nfs4_proc_layoutget(lgp, gfp_flags);
 678         if (IS_ERR(lseg)) {
 679                 switch (PTR_ERR(lseg)) {
 680                 case -ENOMEM:
 681                 case -ERESTARTSYS:
 682                         break;
 683                 default:
 684                         /* remember that LAYOUTGET failed and suspend trying */
 685                         pnfs_layout_io_set_failed(lo, range->iomode);
 686                 }
 687                 return NULL;
 688         }
 689
 690         return lseg;
 691 }
 692
 693 /*
 694  * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
 695  * when the layout segment list is empty.
 696  *
 697  * Note that a pnfs_layout_hdr can exist with an empty layout segment
 698  * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
 699  * deviceid is marked invalid.
 700  */
 701 int
 702 _pnfs_return_layout(struct inode *ino)
 703 {
 704         struct pnfs_layout_hdr *lo = NULL;
 705         struct nfs_inode *nfsi = NFS_I(ino);
 706         LIST_HEAD(tmp_list);
 707         struct nfs4_layoutreturn *lrp;
 708         nfs4_stateid stateid;
 709         int status = 0, empty;
 710
 711         dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
 712
 713         spin_lock(&ino->i_lock);
 714         lo = nfsi->layout;
 715         if (!lo || pnfs_test_layout_returned(lo)) {
 716                 spin_unlock(&ino->i_lock);
 717                 dprintk("NFS: %s no layout to return\n", __func__);
 718                 goto out;
 719         }
 720         stateid = nfsi->layout->plh_stateid;
 721         /* Reference matched in nfs4_layoutreturn_release */
 722         pnfs_get_layout_hdr(lo);
 723         empty = list_empty(&lo->plh_segs);
 724         pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
 725         /* Don't send a LAYOUTRETURN if list was initially empty */
 726         if (empty) {
 727                 spin_unlock(&ino->i_lock);
 728                 pnfs_put_layout_hdr(lo);
 729                 dprintk("NFS: %s no layout segments to return\n", __func__);
 730                 goto out;
 731         }
 732         lo->plh_block_lgets++;
 733         pnfs_mark_layout_returned(lo);
 734         spin_unlock(&ino->i_lock);
 735         pnfs_free_lseg_list(&tmp_list);
 736
 737         WARN_ON(test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags));
 738
 739         lrp = kzalloc(sizeof(*lrp), GFP_KERNEL);
 740         if (unlikely(lrp == NULL)) {
 741                 status = -ENOMEM;
 742                 pnfs_layout_io_set_failed(lo, IOMODE_RW);
 743                 pnfs_layout_io_set_failed(lo, IOMODE_READ);
 744                 pnfs_clear_layout_returned(lo);
 745                 pnfs_put_layout_hdr(lo);
 746                 goto out;
 747         }
 748
 749         lrp->args.stateid = stateid;
 750         lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
 751         lrp->args.inode = ino;
 752         lrp->args.layout = lo;
 753         lrp->clp = NFS_SERVER(ino)->nfs_client;
 754
 755         status = nfs4_proc_layoutreturn(lrp);
 756 out:
 757         dprintk("<-- %s status: %d\n", __func__, status);
 758         return status;
 759 }
 760 EXPORT_SYMBOL_GPL(_pnfs_return_layout);
 761
 762 bool pnfs_roc(struct inode *ino)
 763 {
 764         struct pnfs_layout_hdr *lo;
 765         struct pnfs_layout_segment *lseg, *tmp;
 766         LIST_HEAD(tmp_list);
 767         bool found = false;
 768
 769         spin_lock(&ino->i_lock);
 770         lo = NFS_I(ino)->layout;
 771         if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
 772             test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
 773                 goto out_nolayout;
 774         list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
 775                 if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 776                         mark_lseg_invalid(lseg, &tmp_list);
 777                         found = true;
 778                 }
 779         if (!found)
 780                 goto out_nolayout;
 781         lo->plh_block_lgets++;
 782         pnfs_get_layout_hdr(lo); /* matched in pnfs_roc_release */
 783         spin_unlock(&ino->i_lock);
 784         pnfs_free_lseg_list(&tmp_list);
 785         return true;
 786
 787 out_nolayout:
 788         spin_unlock(&ino->i_lock);
 789         return false;
 790 }
 791
 792 void pnfs_roc_release(struct inode *ino)
 793 {
 794         struct pnfs_layout_hdr *lo;
 795
 796         spin_lock(&ino->i_lock);
 797         lo = NFS_I(ino)->layout;
 798         lo->plh_block_lgets--;
 799         pnfs_put_layout_hdr_locked(lo);
 800         spin_unlock(&ino->i_lock);
 801 }
 802
 803 void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
 804 {
 805         struct pnfs_layout_hdr *lo;
 806
 807         spin_lock(&ino->i_lock);
 808         lo = NFS_I(ino)->layout;
 809         if ((int)(barrier - lo->plh_barrier) > 0)
 810                 lo->plh_barrier = barrier;
 811         spin_unlock(&ino->i_lock);
 812 }
 813
 814 bool pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task)
 815 {
 816         struct nfs_inode *nfsi = NFS_I(ino);
 817         struct pnfs_layout_hdr *lo;
 818         struct pnfs_layout_segment *lseg;
 819         u32 current_seqid;
 820         bool found = false;
 821
 822         spin_lock(&ino->i_lock);
 823         list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list)
 824                 if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
 825                         rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
 826                         found = true;
 827                         goto out;
 828                 }
 829         lo = nfsi->layout;
 830         current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
 831
 832         /* Since close does not return a layout stateid for use as
 833          * a barrier, we choose the worst-case barrier.
 834          */
 835         *barrier = current_seqid + atomic_read(&lo->plh_outstanding);
 836 out:
 837         spin_unlock(&ino->i_lock);
 838         return found;
 839 }
 840
 841 /*
 842  * Compare two layout segments for sorting into layout cache.
 843  * We want to preferentially return RW over RO layouts, so ensure those
 844  * are seen first.
 845  */
 846 static s64
 847 cmp_layout(struct pnfs_layout_range *l1,
 848            struct pnfs_layout_range *l2)
 849 {
 850         s64 d;
 851
 852         /* high offset > low offset */
 853         d = l1->offset - l2->offset;
 854         if (d)
 855                 return d;
 856
 857         /* short length > long length */
 858         d = l2->length - l1->length;
 859         if (d)
 860                 return d;
 861
 862         /* read > read/write */
 863         return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
 864 }
 865
 866 static void
 867 pnfs_layout_insert_lseg(struct pnfs_layout_hdr *lo,
 868                    struct pnfs_layout_segment *lseg)
 869 {
 870         struct pnfs_layout_segment *lp;
 871
 872         dprintk("%s:Begin\n", __func__);
 873
 874         assert_spin_locked(&lo->plh_inode->i_lock);
 875         list_for_each_entry(lp, &lo->plh_segs, pls_list) {
 876                 if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0)
 877                         continue;
 878                 list_add_tail(&lseg->pls_list, &lp->pls_list);
 879                 dprintk("%s: inserted lseg %p "
 880                         "iomode %d offset %llu length %llu before "
 881                         "lp %p iomode %d offset %llu length %llu\n",
 882                         __func__, lseg, lseg->pls_range.iomode,
 883                         lseg->pls_range.offset, lseg->pls_range.length,
 884                         lp, lp->pls_range.iomode, lp->pls_range.offset,
 885                         lp->pls_range.length);
 886                 goto out;
 887         }
 888         list_add_tail(&lseg->pls_list, &lo->plh_segs);
 889         dprintk("%s: inserted lseg %p "
 890                 "iomode %d offset %llu length %llu at tail\n",
 891                 __func__, lseg, lseg->pls_range.iomode,
 892                 lseg->pls_range.offset, lseg->pls_range.length);
 893 out:
 894         pnfs_get_layout_hdr(lo);
 895
 896         dprintk("%s:Return\n", __func__);
 897 }
 898
 899 static struct pnfs_layout_hdr *
 900 alloc_init_layout_hdr(struct inode *ino,
 901                       struct nfs_open_context *ctx,
 902                       gfp_t gfp_flags)
 903 {
 904         struct pnfs_layout_hdr *lo;
 905
 906         lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
 907         if (!lo)
 908                 return NULL;
 909         atomic_set(&lo->plh_refcount, 1);
 910         INIT_LIST_HEAD(&lo->plh_layouts);
 911         INIT_LIST_HEAD(&lo->plh_segs);
 912         INIT_LIST_HEAD(&lo->plh_bulk_recall);
 913         lo->plh_inode = ino;
 914         lo->plh_lc_cred = get_rpccred(ctx->state->owner->so_cred);
 915         return lo;
 916 }
 917
 918 static struct pnfs_layout_hdr *
 919 pnfs_find_alloc_layout(struct inode *ino,
 920                        struct nfs_open_context *ctx,
 921                        gfp_t gfp_flags)
 922 {
 923         struct nfs_inode *nfsi = NFS_I(ino);
 924         struct pnfs_layout_hdr *new = NULL;
 925
 926         dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
 927
 928         assert_spin_locked(&ino->i_lock);
 929         if (nfsi->layout) {
 930                 if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
 931                         return NULL;
 932                 else
 933                         return nfsi->layout;
 934         }
 935         spin_unlock(&ino->i_lock);
 936         new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
 937         spin_lock(&ino->i_lock);
 938
 939         if (likely(nfsi->layout == NULL))       /* Won the race? */
 940                 nfsi->layout = new;
 941         else
 942                 pnfs_free_layout_hdr(new);
 943         return nfsi->layout;
 944 }
 945
 946 /*
 947  * iomode matching rules:
 948  * iomode       lseg    match
 949  * -----        -----   -----
 950  * ANY          READ    true
 951  * ANY          RW      true
 952  * RW           READ    false
 953  * RW           RW      true
 954  * READ         READ    true
 955  * READ         RW      true
 956  */
 957 static int
 958 is_matching_lseg(struct pnfs_layout_range *ls_range,
 959                  struct pnfs_layout_range *range)
 960 {
 961         struct pnfs_layout_range range1;
 962
 963         if ((range->iomode == IOMODE_RW &&
 964              ls_range->iomode != IOMODE_RW) ||
 965             !lo_seg_intersecting(ls_range, range))
 966                 return 0;
 967
 968         /* range1 covers only the first byte in the range */
 969         range1 = *range;
 970         range1.length = 1;
 971         return lo_seg_contained(ls_range, &range1);
 972 }
 973
 974 /*
 975  * lookup range in layout
 976  */
 977 static struct pnfs_layout_segment *
 978 pnfs_find_lseg(struct pnfs_layout_hdr *lo,
 979                 struct pnfs_layout_range *range)
 980 {
 981         struct pnfs_layout_segment *lseg, *ret = NULL;
 982
 983         dprintk("%s:Begin\n", __func__);
 984
 985         assert_spin_locked(&lo->plh_inode->i_lock);
 986         list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
 987                 if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
 988                     is_matching_lseg(&lseg->pls_range, range)) {
 989                         ret = pnfs_get_lseg(lseg);
 990                         break;
 991                 }
 992                 if (lseg->pls_range.offset > range->offset)
 993                         break;
 994         }
 995
 996         dprintk("%s:Return lseg %p ref %d\n",
 997                 __func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
 998         return ret;
 999 }
1000
1001 /*
1002  * Use mdsthreshold hints set at each OPEN to determine if I/O should go
1003  * to the MDS or over pNFS
1004  *
1005  * The nfs_inode read_io and write_io fields are cumulative counters reset
1006  * when there are no layout segments. Note that in pnfs_update_layout iomode
1007  * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
1008  * WRITE request.
1009  *
1010  * A return of true means use MDS I/O.
1011  *
1012  * From rfc 5661:
1013  * If a file's size is smaller than the file size threshold, data accesses
1014  * SHOULD be sent to the metadata server.  If an I/O request has a length that
1015  * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
1016  * server.  If both file size and I/O size are provided, the client SHOULD
1017  * reach or exceed  both thresholds before sending its read or write
1018  * requests to the data server.
1019  */
1020 static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
1021                                      struct inode *ino, int iomode)
1022 {
1023         struct nfs4_threshold *t = ctx->mdsthreshold;
1024         struct nfs_inode *nfsi = NFS_I(ino);
1025         loff_t fsize = i_size_read(ino);
1026         bool size = false, size_set = false, io = false, io_set = false, ret = false;
1027
1028         if (t == NULL)
1029                 return ret;
1030
1031         dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
1032                 __func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
1033
1034         switch (iomode) {
1035         case IOMODE_READ:
1036                 if (t->bm & THRESHOLD_RD) {
1037                         dprintk("%s fsize %llu\n", __func__, fsize);
1038                         size_set = true;
1039                         if (fsize < t->rd_sz)
1040                                 size = true;
1041                 }
1042                 if (t->bm & THRESHOLD_RD_IO) {
1043                         dprintk("%s nfsi->read_io %llu\n", __func__,
1044                                 nfsi->read_io);
1045                         io_set = true;
1046                         if (nfsi->read_io < t->rd_io_sz)
1047                                 io = true;
1048                 }
1049                 break;
1050         case IOMODE_RW:
1051                 if (t->bm & THRESHOLD_WR) {
1052                         dprintk("%s fsize %llu\n", __func__, fsize);
1053                         size_set = true;
1054                         if (fsize < t->wr_sz)
1055                                 size = true;
1056                 }
1057                 if (t->bm & THRESHOLD_WR_IO) {
1058                         dprintk("%s nfsi->write_io %llu\n", __func__,
1059                                 nfsi->write_io);
1060                         io_set = true;
1061                         if (nfsi->write_io < t->wr_io_sz)
1062                                 io = true;
1063                 }
1064                 break;
1065         }
1066         if (size_set && io_set) {
1067                 if (size && io)
1068                         ret = true;
1069         } else if (size || io)
1070                 ret = true;
1071
1072         dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
1073         return ret;
1074 }
1075
1076 /*
1077  * Layout segment is retreived from the server if not cached.
1078  * The appropriate layout segment is referenced and returned to the caller.
1079  */
1080 struct pnfs_layout_segment *
1081 pnfs_update_layout(struct inode *ino,
1082                    struct nfs_open_context *ctx,
1083                    loff_t pos,
1084                    u64 count,
1085                    enum pnfs_iomode iomode,
1086                    gfp_t gfp_flags)
1087 {
1088         struct pnfs_layout_range arg = {
1089                 .iomode = iomode,
1090                 .offset = pos,
1091                 .length = count,
1092         };
1093         unsigned pg_offset;
1094         struct nfs_server *server = NFS_SERVER(ino);
1095         struct nfs_client *clp = server->nfs_client;
1096         struct pnfs_layout_hdr *lo;
1097         struct pnfs_layout_segment *lseg = NULL;
1098         bool first = false;
1099
1100         if (!pnfs_enabled_sb(NFS_SERVER(ino)))
1101                 goto out;
1102
1103         if (pnfs_within_mdsthreshold(ctx, ino, iomode))
1104                 goto out;
1105
1106         spin_lock(&ino->i_lock);
1107         lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
1108         if (lo == NULL) {
1109                 spin_unlock(&ino->i_lock);
1110                 goto out;
1111         }
1112
1113         /* Do we even need to bother with this? */
1114         if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1115                 dprintk("%s matches recall, use MDS\n", __func__);
1116                 goto out_unlock;
1117         }
1118
1119         /* if LAYOUTGET already failed once we don't try again */
1120         if (pnfs_layout_io_test_failed(lo, iomode))
1121                 goto out_unlock;
1122
1123         /* Check to see if the layout for the given range already exists */
1124         lseg = pnfs_find_lseg(lo, &arg);
1125         if (lseg)
1126                 goto out_unlock;
1127
1128         if (pnfs_layoutgets_blocked(lo, NULL, 0))
1129                 goto out_unlock;
1130         atomic_inc(&lo->plh_outstanding);
1131
1132         pnfs_get_layout_hdr(lo);
1133         if (list_empty(&lo->plh_segs))
1134                 first = true;
1135
1136         /* Enable LAYOUTRETURNs */
1137         pnfs_clear_layout_returned(lo);
1138
1139         spin_unlock(&ino->i_lock);
1140         if (first) {
1141                 /* The lo must be on the clp list if there is any
1142                  * chance of a CB_LAYOUTRECALL(FILE) coming in.
1143                  */
1144                 spin_lock(&clp->cl_lock);
1145                 BUG_ON(!list_empty(&lo->plh_layouts));
1146                 list_add_tail(&lo->plh_layouts, &server->layouts);
1147                 spin_unlock(&clp->cl_lock);
1148         }
1149
1150         pg_offset = arg.offset & ~PAGE_CACHE_MASK;
1151         if (pg_offset) {
1152                 arg.offset -= pg_offset;
1153                 arg.length += pg_offset;
1154         }
1155         if (arg.length != NFS4_MAX_UINT64)
1156                 arg.length = PAGE_CACHE_ALIGN(arg.length);
1157
1158         lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
1159         if (!lseg && first) {
1160                 spin_lock(&clp->cl_lock);
1161                 list_del_init(&lo->plh_layouts);
1162                 spin_unlock(&clp->cl_lock);
1163         }
1164         atomic_dec(&lo->plh_outstanding);
1165 out_put_layout_hdr:
1166         pnfs_put_layout_hdr(lo);
1167 out:
1168         dprintk("%s: inode %s/%llu pNFS layout segment %s for "
1169                         "(%s, offset: %llu, length: %llu)\n",
1170                         __func__, ino->i_sb->s_id,
1171                         (unsigned long long)NFS_FILEID(ino),
1172                         lseg == NULL ? "not found" : "found",
1173                         iomode==IOMODE_RW ?  "read/write" : "read-only",
1174                         (unsigned long long)pos,
1175                         (unsigned long long)count);
1176         return lseg;
1177 out_unlock:
1178         spin_unlock(&ino->i_lock);
1179         goto out_put_layout_hdr;
1180 }
1181 EXPORT_SYMBOL_GPL(pnfs_update_layout);
1182
1183 struct pnfs_layout_segment *
1184 pnfs_layout_process(struct nfs4_layoutget *lgp)
1185 {
1186         struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
1187         struct nfs4_layoutget_res *res = &lgp->res;
1188         struct pnfs_layout_segment *lseg;
1189         struct inode *ino = lo->plh_inode;
1190         int status = 0;
1191
1192         /* Inject layout blob into I/O device driver */
1193         lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
1194         if (!lseg || IS_ERR(lseg)) {
1195                 if (!lseg)
1196                         status = -ENOMEM;
1197                 else
1198                         status = PTR_ERR(lseg);
1199                 dprintk("%s: Could not allocate layout: error %d\n",
1200                        __func__, status);
1201                 goto out;
1202         }
1203
1204         spin_lock(&ino->i_lock);
1205         if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
1206                 dprintk("%s forget reply due to recall\n", __func__);
1207                 goto out_forget_reply;
1208         }
1209
1210         if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) {
1211                 dprintk("%s forget reply due to state\n", __func__);
1212                 goto out_forget_reply;
1213         }
1214         init_lseg(lo, lseg);
1215         lseg->pls_range = res->range;
1216         pnfs_get_lseg(lseg);
1217         pnfs_layout_insert_lseg(lo, lseg);
1218
1219         if (res->return_on_close) {
1220                 set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
1221                 set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
1222         }
1223
1224         /* Done processing layoutget. Set the layout stateid */
1225         pnfs_set_layout_stateid(lo, &res->stateid, false);
1226         spin_unlock(&ino->i_lock);
1227         return lseg;
1228 out:
1229         return ERR_PTR(status);
1230
1231 out_forget_reply:
1232         spin_unlock(&ino->i_lock);
1233         lseg->pls_layout = lo;
1234         NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
1235         goto out;
1236 }
1237
1238 void
1239 pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
1240 {
1241         BUG_ON(pgio->pg_lseg != NULL);
1242
1243         if (req->wb_offset != req->wb_pgbase) {
1244                 nfs_pageio_reset_read_mds(pgio);
1245                 return;
1246         }
1247         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1248                                            req->wb_context,
1249                                            req_offset(req),
1250                                            req->wb_bytes,
1251                                            IOMODE_READ,
1252                                            GFP_KERNEL);
1253         /* If no lseg, fall back to read through mds */
1254         if (pgio->pg_lseg == NULL)
1255                 nfs_pageio_reset_read_mds(pgio);
1256
1257 }
1258 EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
1259
1260 void
1261 pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
1262 {
1263         BUG_ON(pgio->pg_lseg != NULL);
1264
1265         if (req->wb_offset != req->wb_pgbase) {
1266                 nfs_pageio_reset_write_mds(pgio);
1267                 return;
1268         }
1269         pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
1270                                            req->wb_context,
1271                                            req_offset(req),
1272                                            req->wb_bytes,
1273                                            IOMODE_RW,
1274                                            GFP_NOFS);
1275         /* If no lseg, fall back to write through mds */
1276         if (pgio->pg_lseg == NULL)
1277                 nfs_pageio_reset_write_mds(pgio);
1278 }
1279 EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
1280
1281 void
1282 pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode,
1283                       const struct nfs_pgio_completion_ops *compl_ops)
1284 {
1285         struct nfs_server *server = NFS_SERVER(inode);
1286         struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
1287
1288         if (ld == NULL)
1289                 nfs_pageio_init_read(pgio, inode, compl_ops);
1290         else
1291                 nfs_pageio_init(pgio, inode, ld->pg_read_ops, compl_ops, server->rsize, 0);
1292 }
1293
1294 void
1295 pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode,
1296                        int ioflags,
1297                        const struct nfs_pgio_completion_ops *compl_ops)
1298 {
1299         struct nfs_server *server = NFS_SERVER(inode);
1300         struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
1301
1302         if (ld == NULL)
1303                 nfs_pageio_init_write(pgio, inode, ioflags, compl_ops);
1304         else
1305                 nfs_pageio_init(pgio, inode, ld->pg_write_ops, compl_ops, server->wsize, ioflags);
1306 }
1307
1308 bool
1309 pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
1310                      struct nfs_page *req)
1311 {
1312         if (pgio->pg_lseg == NULL)
1313                 return nfs_generic_pg_test(pgio, prev, req);
1314
1315         /*
1316          * Test if a nfs_page is fully contained in the pnfs_layout_range.
1317          * Note that this test makes several assumptions:
1318          * - that the previous nfs_page in the struct nfs_pageio_descriptor
1319          *   is known to lie within the range.
1320          *   - that the nfs_page being tested is known to be contiguous with the
1321          *   previous nfs_page.
1322          *   - Layout ranges are page aligned, so we only have to test the
1323          *   start offset of the request.
1324          *
1325          * Please also note that 'end_offset' is actually the offset of the
1326          * first byte that lies outside the pnfs_layout_range. FIXME?
1327          *
1328          */
1329         return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset,
1330                                          pgio->pg_lseg->pls_range.length);
1331 }
1332 EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
1333
1334 int pnfs_write_done_resend_to_mds(struct inode *inode,
1335                                 struct list_head *head,
1336                                 const struct nfs_pgio_completion_ops *compl_ops)
1337 {
1338         struct nfs_pageio_descriptor pgio;
1339         LIST_HEAD(failed);
1340
1341         /* Resend all requests through the MDS */
1342         nfs_pageio_init_write(&pgio, inode, FLUSH_STABLE, compl_ops);
1343         while (!list_empty(head)) {
1344                 struct nfs_page *req = nfs_list_entry(head->next);
1345
1346                 nfs_list_remove_request(req);
1347                 if (!nfs_pageio_add_request(&pgio, req))
1348                         nfs_list_add_request(req, &failed);
1349         }
1350         nfs_pageio_complete(&pgio);
1351
1352         if (!list_empty(&failed)) {
1353                 /* For some reason our attempt to resend pages. Mark the
1354                  * overall send request as having failed, and let
1355                  * nfs_writeback_release_full deal with the error.
1356                  */
1357                 list_move(&failed, head);
1358                 return -EIO;
1359         }
1360         return 0;
1361 }
1362 EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
1363
1364 static void pnfs_ld_handle_write_error(struct nfs_write_data *data)
1365 {
1366         struct nfs_pgio_header *hdr = data->header;
1367
1368         dprintk("pnfs write error = %d\n", hdr->pnfs_error);
1369         if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1370             PNFS_LAYOUTRET_ON_ERROR) {
1371                 clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
1372                 pnfs_return_layout(hdr->inode);
1373         }
1374         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
1375                 data->task.tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
1376                                                         &hdr->pages,
1377                                                         hdr->completion_ops);
1378 }
1379
1380 /*
1381  * Called by non rpc-based layout drivers
1382  */
1383 void pnfs_ld_write_done(struct nfs_write_data *data)
1384 {
1385         struct nfs_pgio_header *hdr = data->header;
1386
1387         if (!hdr->pnfs_error) {
1388                 pnfs_set_layoutcommit(data);
1389                 hdr->mds_ops->rpc_call_done(&data->task, data);
1390         } else
1391                 pnfs_ld_handle_write_error(data);
1392         hdr->mds_ops->rpc_release(data);
1393 }
1394 EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
1395
1396 static void
1397 pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
1398                 struct nfs_write_data *data)
1399 {
1400         struct nfs_pgio_header *hdr = data->header;
1401
1402         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1403                 list_splice_tail_init(&hdr->pages, &desc->pg_list);
1404                 nfs_pageio_reset_write_mds(desc);
1405                 desc->pg_recoalesce = 1;
1406         }
1407         nfs_writedata_release(data);
1408 }
1409
1410 static enum pnfs_try_status
1411 pnfs_try_to_write_data(struct nfs_write_data *wdata,
1412                         const struct rpc_call_ops *call_ops,
1413                         struct pnfs_layout_segment *lseg,
1414                         int how)
1415 {
1416         struct nfs_pgio_header *hdr = wdata->header;
1417         struct inode *inode = hdr->inode;
1418         enum pnfs_try_status trypnfs;
1419         struct nfs_server *nfss = NFS_SERVER(inode);
1420
1421         hdr->mds_ops = call_ops;
1422
1423         dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
1424                 inode->i_ino, wdata->args.count, wdata->args.offset, how);
1425         trypnfs = nfss->pnfs_curr_ld->write_pagelist(wdata, how);
1426         if (trypnfs != PNFS_NOT_ATTEMPTED)
1427                 nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
1428         dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
1429         return trypnfs;
1430 }
1431
1432 static void
1433 pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *head, int how)
1434 {
1435         struct nfs_write_data *data;
1436         const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
1437         struct pnfs_layout_segment *lseg = desc->pg_lseg;
1438
1439         desc->pg_lseg = NULL;
1440         while (!list_empty(head)) {
1441                 enum pnfs_try_status trypnfs;
1442
1443                 data = list_first_entry(head, struct nfs_write_data, list);
1444                 list_del_init(&data->list);
1445
1446                 trypnfs = pnfs_try_to_write_data(data, call_ops, lseg, how);
1447                 if (trypnfs == PNFS_NOT_ATTEMPTED)
1448                         pnfs_write_through_mds(desc, data);
1449         }
1450         pnfs_put_lseg(lseg);
1451 }
1452
1453 static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
1454 {
1455         pnfs_put_lseg(hdr->lseg);
1456         nfs_writehdr_free(hdr);
1457 }
1458 EXPORT_SYMBOL_GPL(pnfs_writehdr_free);
1459
1460 int
1461 pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
1462 {
1463         struct nfs_write_header *whdr;
1464         struct nfs_pgio_header *hdr;
1465         int ret;
1466
1467         whdr = nfs_writehdr_alloc();
1468         if (!whdr) {
1469                 desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1470                 pnfs_put_lseg(desc->pg_lseg);
1471                 desc->pg_lseg = NULL;
1472                 return -ENOMEM;
1473         }
1474         hdr = &whdr->header;
1475         nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
1476         hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
1477         atomic_inc(&hdr->refcnt);
1478         ret = nfs_generic_flush(desc, hdr);
1479         if (ret != 0) {
1480                 pnfs_put_lseg(desc->pg_lseg);
1481                 desc->pg_lseg = NULL;
1482         } else
1483                 pnfs_do_multiple_writes(desc, &hdr->rpc_list, desc->pg_ioflags);
1484         if (atomic_dec_and_test(&hdr->refcnt))
1485                 hdr->completion_ops->completion(hdr);
1486         return ret;
1487 }
1488 EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
1489
1490 int pnfs_read_done_resend_to_mds(struct inode *inode,
1491                                 struct list_head *head,
1492                                 const struct nfs_pgio_completion_ops *compl_ops)
1493 {
1494         struct nfs_pageio_descriptor pgio;
1495         LIST_HEAD(failed);
1496
1497         /* Resend all requests through the MDS */
1498         nfs_pageio_init_read(&pgio, inode, compl_ops);
1499         while (!list_empty(head)) {
1500                 struct nfs_page *req = nfs_list_entry(head->next);
1501
1502                 nfs_list_remove_request(req);
1503                 if (!nfs_pageio_add_request(&pgio, req))
1504                         nfs_list_add_request(req, &failed);
1505         }
1506         nfs_pageio_complete(&pgio);
1507
1508         if (!list_empty(&failed)) {
1509                 list_move(&failed, head);
1510                 return -EIO;
1511         }
1512         return 0;
1513 }
1514 EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
1515
1516 static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
1517 {
1518         struct nfs_pgio_header *hdr = data->header;
1519
1520         dprintk("pnfs read error = %d\n", hdr->pnfs_error);
1521         if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
1522             PNFS_LAYOUTRET_ON_ERROR) {
1523                 clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
1524                 pnfs_return_layout(hdr->inode);
1525         }
1526         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
1527                 data->task.tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
1528                                                         &hdr->pages,
1529                                                         hdr->completion_ops);
1530 }
1531
1532 /*
1533  * Called by non rpc-based layout drivers
1534  */
1535 void pnfs_ld_read_done(struct nfs_read_data *data)
1536 {
1537         struct nfs_pgio_header *hdr = data->header;
1538
1539         if (likely(!hdr->pnfs_error)) {
1540                 __nfs4_read_done_cb(data);
1541                 hdr->mds_ops->rpc_call_done(&data->task, data);
1542         } else
1543                 pnfs_ld_handle_read_error(data);
1544         hdr->mds_ops->rpc_release(data);
1545 }
1546 EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
1547
1548 static void
1549 pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
1550                 struct nfs_read_data *data)
1551 {
1552         struct nfs_pgio_header *hdr = data->header;
1553
1554         if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
1555                 list_splice_tail_init(&hdr->pages, &desc->pg_list);
1556                 nfs_pageio_reset_read_mds(desc);
1557                 desc->pg_recoalesce = 1;
1558         }
1559         nfs_readdata_release(data);
1560 }
1561
1562 /*
1563  * Call the appropriate parallel I/O subsystem read function.
1564  */
1565 static enum pnfs_try_status
1566 pnfs_try_to_read_data(struct nfs_read_data *rdata,
1567                        const struct rpc_call_ops *call_ops,
1568                        struct pnfs_layout_segment *lseg)
1569 {
1570         struct nfs_pgio_header *hdr = rdata->header;
1571         struct inode *inode = hdr->inode;
1572         struct nfs_server *nfss = NFS_SERVER(inode);
1573         enum pnfs_try_status trypnfs;
1574
1575         hdr->mds_ops = call_ops;
1576
1577         dprintk("%s: Reading ino:%lu %u@%llu\n",
1578                 __func__, inode->i_ino, rdata->args.count, rdata->args.offset);
1579
1580         trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata);
1581         if (trypnfs != PNFS_NOT_ATTEMPTED)
1582                 nfs_inc_stats(inode, NFSIOS_PNFS_READ);
1583         dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
1584         return trypnfs;
1585 }
1586
1587 static void
1588 pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)
1589 {
1590         struct nfs_read_data *data;
1591         const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
1592         struct pnfs_layout_segment *lseg = desc->pg_lseg;
1593
1594         desc->pg_lseg = NULL;
1595         while (!list_empty(head)) {
1596                 enum pnfs_try_status trypnfs;
1597
1598                 data = list_first_entry(head, struct nfs_read_data, list);
1599                 list_del_init(&data->list);
1600
1601                 trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
1602                 if (trypnfs == PNFS_NOT_ATTEMPTED)
1603                         pnfs_read_through_mds(desc, data);
1604         }
1605         pnfs_put_lseg(lseg);
1606 }
1607
1608 static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
1609 {
1610         pnfs_put_lseg(hdr->lseg);
1611         nfs_readhdr_free(hdr);
1612 }
1613 EXPORT_SYMBOL_GPL(pnfs_readhdr_free);
1614
1615 int
1616 pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
1617 {
1618         struct nfs_read_header *rhdr;
1619         struct nfs_pgio_header *hdr;
1620         int ret;
1621
1622         rhdr = nfs_readhdr_alloc();
1623         if (!rhdr) {
1624                 desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1625                 ret = -ENOMEM;
1626                 pnfs_put_lseg(desc->pg_lseg);
1627                 desc->pg_lseg = NULL;
1628                 return ret;
1629         }
1630         hdr = &rhdr->header;
1631         nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
1632         hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
1633         atomic_inc(&hdr->refcnt);
1634         ret = nfs_generic_pagein(desc, hdr);
1635         if (ret != 0) {
1636                 pnfs_put_lseg(desc->pg_lseg);
1637                 desc->pg_lseg = NULL;
1638         } else
1639                 pnfs_do_multiple_reads(desc, &hdr->rpc_list);
1640         if (atomic_dec_and_test(&hdr->refcnt))
1641                 hdr->completion_ops->completion(hdr);
1642         return ret;
1643 }
1644 EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
1645
1646 /*
1647  * There can be multiple RW segments.
1648  */
1649 static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
1650 {
1651         struct pnfs_layout_segment *lseg;
1652
1653         list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
1654                 if (lseg->pls_range.iomode == IOMODE_RW &&
1655                     test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
1656                         list_add(&lseg->pls_lc_list, listp);
1657         }
1658 }
1659
1660 void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
1661 {
1662         pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
1663 }
1664 EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
1665
1666 void
1667 pnfs_set_layoutcommit(struct nfs_write_data *wdata)
1668 {
1669         struct nfs_pgio_header *hdr = wdata->header;
1670         struct inode *inode = hdr->inode;
1671         struct nfs_inode *nfsi = NFS_I(inode);
1672         loff_t end_pos = wdata->mds_offset + wdata->res.count;
1673         bool mark_as_dirty = false;
1674
1675         spin_lock(&inode->i_lock);
1676         if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
1677                 mark_as_dirty = true;
1678                 dprintk("%s: Set layoutcommit for inode %lu ",
1679                         __func__, inode->i_ino);
1680         }
1681         if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &hdr->lseg->pls_flags)) {
1682                 /* references matched in nfs4_layoutcommit_release */
1683                 pnfs_get_lseg(hdr->lseg);
1684         }
1685         if (end_pos > nfsi->layout->plh_lwb)
1686                 nfsi->layout->plh_lwb = end_pos;
1687         spin_unlock(&inode->i_lock);
1688         dprintk("%s: lseg %p end_pos %llu\n",
1689                 __func__, hdr->lseg, nfsi->layout->plh_lwb);
1690
1691         /* if pnfs_layoutcommit_inode() runs between inode locks, the next one
1692          * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
1693         if (mark_as_dirty)
1694                 mark_inode_dirty_sync(inode);
1695 }
1696 EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
1697
1698 void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
1699 {
1700         struct nfs_server *nfss = NFS_SERVER(data->args.inode);
1701
1702         if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
1703                 nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
1704 }
1705
1706 /*
1707  * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
1708  * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
1709  * data to disk to allow the server to recover the data if it crashes.
1710  * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
1711  * is off, and a COMMIT is sent to a data server, or
1712  * if WRITEs to a data server return NFS_DATA_SYNC.
1713  */
1714 int
1715 pnfs_layoutcommit_inode(struct inode *inode, bool sync)
1716 {
1717         struct nfs4_layoutcommit_data *data;
1718         struct nfs_inode *nfsi = NFS_I(inode);
1719         loff_t end_pos;
1720         int status = 0;
1721
1722         dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
1723
1724         if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1725                 return 0;
1726
1727         /* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
1728         data = kzalloc(sizeof(*data), GFP_NOFS);
1729         if (!data) {
1730                 status = -ENOMEM;
1731                 goto out;
1732         }
1733
1734         if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
1735                 goto out_free;
1736
1737         if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
1738                 if (!sync) {
1739                         status = -EAGAIN;
1740                         goto out_free;
1741                 }
1742                 status = wait_on_bit_lock(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING,
1743                                         nfs_wait_bit_killable, TASK_KILLABLE);
1744                 if (status)
1745                         goto out_free;
1746         }
1747
1748         INIT_LIST_HEAD(&data->lseg_list);
1749         spin_lock(&inode->i_lock);
1750         if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
1751                 clear_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags);
1752                 spin_unlock(&inode->i_lock);
1753                 wake_up_bit(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING);
1754                 goto out_free;
1755         }
1756
1757         pnfs_list_write_lseg(inode, &data->lseg_list);
1758
1759         end_pos = nfsi->layout->plh_lwb;
1760         nfsi->layout->plh_lwb = 0;
1761
1762         nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
1763         spin_unlock(&inode->i_lock);
1764
1765         data->args.inode = inode;
1766         data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
1767         nfs_fattr_init(&data->fattr);
1768         data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
1769         data->res.fattr = &data->fattr;
1770         data->args.lastbytewritten = end_pos - 1;
1771         data->res.server = NFS_SERVER(inode);
1772
1773         status = nfs4_proc_layoutcommit(data, sync);
1774 out:
1775         if (status)
1776                 mark_inode_dirty_sync(inode);
1777         dprintk("<-- %s status %d\n", __func__, status);
1778         return status;
1779 out_free:
1780         kfree(data);
1781         goto out;
1782 }
1783
1784 struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
1785 {
1786         struct nfs4_threshold *thp;
1787
1788         thp = kzalloc(sizeof(*thp), GFP_NOFS);
1789         if (!thp) {
1790                 dprintk("%s mdsthreshold allocation failed\n", __func__);
1791                 return NULL;
1792         }
1793         return thp;
1794 }