fs/exofs/inode.c

   1 /*
   2  * Copyright (C) 2005, 2006
   3  * Avishay Traeger (avishay@gmail.com)
   4  * Copyright (C) 2008, 2009
   5  * Boaz Harrosh <bharrosh@panasas.com>
   6  *
   7  * Copyrights for code taken from ext2:
   8  *     Copyright (C) 1992, 1993, 1994, 1995
   9  *     Remy Card (card@masi.ibp.fr)
  10  *     Laboratoire MASI - Institut Blaise Pascal
  11  *     Universite Pierre et Marie Curie (Paris VI)
  12  *     from
  13  *     linux/fs/minix/inode.c
  14  *     Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  * This file is part of exofs.
  17  *
  18  * exofs is free software; you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation.  Since it is based on ext2, and the only
  21  * valid version of GPL for the Linux kernel is version 2, the only valid
  22  * version of GPL for exofs is version 2.
  23  *
  24  * exofs is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with exofs; if not, write to the Free Software
  31  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  32  */
  33
  34 #include <linux/slab.h>
  35
  36 #include "exofs.h"
  37
  38 #define EXOFS_DBGMSG2(M...) do {} while (0)
  39
  40 enum {MAX_PAGES_KMALLOC = PAGE_SIZE / sizeof(struct page *), };
  41
  42 unsigned exofs_max_io_pages(struct ore_layout *layout,
  43                             unsigned expected_pages)
  44 {
  45         unsigned pages = min_t(unsigned, expected_pages, MAX_PAGES_KMALLOC);
  46
  47         /* TODO: easily support bio chaining */
  48         pages =  min_t(unsigned, pages, layout->max_io_length / PAGE_SIZE);
  49         return pages;
  50 }
  51
  52 struct page_collect {
  53         struct exofs_sb_info *sbi;
  54         struct inode *inode;
  55         unsigned expected_pages;
  56         struct ore_io_state *ios;
  57
  58         struct page **pages;
  59         unsigned alloc_pages;
  60         unsigned nr_pages;
  61         unsigned long length;
  62         loff_t pg_first; /* keep 64bit also in 32-arches */
  63         bool read_4_write; /* This means two things: that the read is sync
  64                             * And the pages should not be unlocked.
  65                             */
  66         struct page *that_locked_page;
  67 };
  68
  69 static void _pcol_init(struct page_collect *pcol, unsigned expected_pages,
  70                        struct inode *inode)
  71 {
  72         struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
  73
  74         pcol->sbi = sbi;
  75         pcol->inode = inode;
  76         pcol->expected_pages = expected_pages;
  77
  78         pcol->ios = NULL;
  79         pcol->pages = NULL;
  80         pcol->alloc_pages = 0;
  81         pcol->nr_pages = 0;
  82         pcol->length = 0;
  83         pcol->pg_first = -1;
  84         pcol->read_4_write = false;
  85         pcol->that_locked_page = NULL;
  86 }
  87
  88 static void _pcol_reset(struct page_collect *pcol)
  89 {
  90         pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
  91
  92         pcol->pages = NULL;
  93         pcol->alloc_pages = 0;
  94         pcol->nr_pages = 0;
  95         pcol->length = 0;
  96         pcol->pg_first = -1;
  97         pcol->ios = NULL;
  98         pcol->that_locked_page = NULL;
  99
 100         /* this is probably the end of the loop but in writes
 101          * it might not end here. don't be left with nothing
 102          */
 103         if (!pcol->expected_pages)
 104                 pcol->expected_pages = MAX_PAGES_KMALLOC;
 105 }
 106
 107 static int pcol_try_alloc(struct page_collect *pcol)
 108 {
 109         unsigned pages;
 110
 111         /* TODO: easily support bio chaining */
 112         pages =  exofs_max_io_pages(&pcol->sbi->layout, pcol->expected_pages);
 113
 114         for (; pages; pages >>= 1) {
 115                 pcol->pages = kmalloc(pages * sizeof(struct page *),
 116                                       GFP_KERNEL);
 117                 if (likely(pcol->pages)) {
 118                         pcol->alloc_pages = pages;
 119                         return 0;
 120                 }
 121         }
 122
 123         EXOFS_ERR("Failed to kmalloc expected_pages=%u\n",
 124                   pcol->expected_pages);
 125         return -ENOMEM;
 126 }
 127
 128 static void pcol_free(struct page_collect *pcol)
 129 {
 130         kfree(pcol->pages);
 131         pcol->pages = NULL;
 132
 133         if (pcol->ios) {
 134                 ore_put_io_state(pcol->ios);
 135                 pcol->ios = NULL;
 136         }
 137 }
 138
 139 static int pcol_add_page(struct page_collect *pcol, struct page *page,
 140                          unsigned len)
 141 {
 142         if (unlikely(pcol->nr_pages >= pcol->alloc_pages))
 143                 return -ENOMEM;
 144
 145         pcol->pages[pcol->nr_pages++] = page;
 146         pcol->length += len;
 147         return 0;
 148 }
 149
 150 enum {PAGE_WAS_NOT_IN_IO = 17};
 151 static int update_read_page(struct page *page, int ret)
 152 {
 153         switch (ret) {
 154         case 0:
 155                 /* Everything is OK */
 156                 SetPageUptodate(page);
 157                 if (PageError(page))
 158                         ClearPageError(page);
 159                 break;
 160         case -EFAULT:
 161                 /* In this case we were trying to read something that wasn't on
 162                  * disk yet - return a page full of zeroes.  This should be OK,
 163                  * because the object should be empty (if there was a write
 164                  * before this read, the read would be waiting with the page
 165                  * locked */
 166                 clear_highpage(page);
 167
 168                 SetPageUptodate(page);
 169                 if (PageError(page))
 170                         ClearPageError(page);
 171                 EXOFS_DBGMSG("recovered read error\n");
 172                 /* fall through */
 173         case PAGE_WAS_NOT_IN_IO:
 174                 ret = 0; /* recovered error */
 175                 break;
 176         default:
 177                 SetPageError(page);
 178         }
 179         return ret;
 180 }
 181
 182 static void update_write_page(struct page *page, int ret)
 183 {
 184         if (unlikely(ret == PAGE_WAS_NOT_IN_IO))
 185                 return; /* don't pass start don't collect $200 */
 186
 187         if (ret) {
 188                 mapping_set_error(page->mapping, ret);
 189                 SetPageError(page);
 190         }
 191         end_page_writeback(page);
 192 }
 193
 194 /* Called at the end of reads, to optionally unlock pages and update their
 195  * status.
 196  */
 197 static int __readpages_done(struct page_collect *pcol)
 198 {
 199         int i;
 200         u64 good_bytes;
 201         u64 length = 0;
 202         int ret = ore_check_io(pcol->ios, NULL);
 203
 204         if (likely(!ret)) {
 205                 good_bytes = pcol->length;
 206                 ret = PAGE_WAS_NOT_IN_IO;
 207         } else {
 208                 good_bytes = 0;
 209         }
 210
 211         EXOFS_DBGMSG2("readpages_done(0x%lx) good_bytes=0x%llx"
 212                      " length=0x%lx nr_pages=%u\n",
 213                      pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 214                      pcol->nr_pages);
 215
 216         for (i = 0; i < pcol->nr_pages; i++) {
 217                 struct page *page = pcol->pages[i];
 218                 struct inode *inode = page->mapping->host;
 219                 int page_stat;
 220
 221                 if (inode != pcol->inode)
 222                         continue; /* osd might add more pages at end */
 223
 224                 if (likely(length < good_bytes))
 225                         page_stat = 0;
 226                 else
 227                         page_stat = ret;
 228
 229                 EXOFS_DBGMSG2("    readpages_done(0x%lx, 0x%lx) %s\n",
 230                           inode->i_ino, page->index,
 231                           page_stat ? "bad_bytes" : "good_bytes");
 232
 233                 ret = update_read_page(page, page_stat);
 234                 if (!pcol->read_4_write)
 235                         unlock_page(page);
 236                 length += PAGE_SIZE;
 237         }
 238
 239         pcol_free(pcol);
 240         EXOFS_DBGMSG2("readpages_done END\n");
 241         return ret;
 242 }
 243
 244 /* callback of async reads */
 245 static void readpages_done(struct ore_io_state *ios, void *p)
 246 {
 247         struct page_collect *pcol = p;
 248
 249         __readpages_done(pcol);
 250         atomic_dec(&pcol->sbi->s_curr_pending);
 251         kfree(pcol);
 252 }
 253
 254 static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
 255 {
 256         int i;
 257
 258         for (i = 0; i < pcol->nr_pages; i++) {
 259                 struct page *page = pcol->pages[i];
 260
 261                 if (rw == READ)
 262                         update_read_page(page, ret);
 263                 else
 264                         update_write_page(page, ret);
 265
 266                 unlock_page(page);
 267         }
 268 }
 269
 270 static int _maybe_not_all_in_one_io(struct ore_io_state *ios,
 271         struct page_collect *pcol_src, struct page_collect *pcol)
 272 {
 273         /* length was wrong or offset was not page aligned */
 274         BUG_ON(pcol_src->nr_pages < ios->nr_pages);
 275
 276         if (pcol_src->nr_pages > ios->nr_pages) {
 277                 struct page **src_page;
 278                 unsigned pages_less = pcol_src->nr_pages - ios->nr_pages;
 279                 unsigned long len_less = pcol_src->length - ios->length;
 280                 unsigned i;
 281                 int ret;
 282
 283                 /* This IO was trimmed */
 284                 pcol_src->nr_pages = ios->nr_pages;
 285                 pcol_src->length = ios->length;
 286
 287                 /* Left over pages are passed to the next io */
 288                 pcol->expected_pages += pages_less;
 289                 pcol->nr_pages = pages_less;
 290                 pcol->length = len_less;
 291                 src_page = pcol_src->pages + pcol_src->nr_pages;
 292                 pcol->pg_first = (*src_page)->index;
 293
 294                 ret = pcol_try_alloc(pcol);
 295                 if (unlikely(ret))
 296                         return ret;
 297
 298                 for (i = 0; i < pages_less; ++i)
 299                         pcol->pages[i] = *src_page++;
 300
 301                 EXOFS_DBGMSG("Length was adjusted nr_pages=0x%x "
 302                         "pages_less=0x%x expected_pages=0x%x "
 303                         "next_offset=0x%llx next_len=0x%lx\n",
 304                         pcol_src->nr_pages, pages_less, pcol->expected_pages,
 305                         pcol->pg_first * PAGE_SIZE, pcol->length);
 306         }
 307         return 0;
 308 }
 309
 310 static int read_exec(struct page_collect *pcol)
 311 {
 312         struct exofs_i_info *oi = exofs_i(pcol->inode);
 313         struct ore_io_state *ios;
 314         struct page_collect *pcol_copy = NULL;
 315         int ret;
 316
 317         if (!pcol->pages)
 318                 return 0;
 319
 320         if (!pcol->ios) {
 321                 int ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, true,
 322                                              pcol->pg_first << PAGE_CACHE_SHIFT,
 323                                              pcol->length, &pcol->ios);
 324
 325                 if (ret)
 326                         return ret;
 327         }
 328
 329         ios = pcol->ios;
 330         ios->pages = pcol->pages;
 331
 332         if (pcol->read_4_write) {
 333                 ore_read(pcol->ios);
 334                 return __readpages_done(pcol);
 335         }
 336
 337         pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 338         if (!pcol_copy) {
 339                 ret = -ENOMEM;
 340                 goto err;
 341         }
 342
 343         *pcol_copy = *pcol;
 344         ios->done = readpages_done;
 345         ios->private = pcol_copy;
 346
 347         /* pages ownership was passed to pcol_copy */
 348         _pcol_reset(pcol);
 349
 350         ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol);
 351         if (unlikely(ret))
 352                 goto err;
 353
 354         EXOFS_DBGMSG2("read_exec(0x%lx) offset=0x%llx length=0x%llx\n",
 355                 pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length));
 356
 357         ret = ore_read(ios);
 358         if (unlikely(ret))
 359                 goto err;
 360
 361         atomic_inc(&pcol->sbi->s_curr_pending);
 362
 363         return 0;
 364
 365 err:
 366         if (!pcol->read_4_write)
 367                 _unlock_pcol_pages(pcol, ret, READ);
 368
 369         pcol_free(pcol);
 370
 371         kfree(pcol_copy);
 372         return ret;
 373 }
 374
 375 /* readpage_strip is called either directly from readpage() or by the VFS from
 376  * within read_cache_pages(), to add one more page to be read. It will try to
 377  * collect as many contiguous pages as posible. If a discontinuity is
 378  * encountered, or it runs out of resources, it will submit the previous segment
 379  * and will start a new collection. Eventually caller must submit the last
 380  * segment if present.
 381  */
 382 static int readpage_strip(void *data, struct page *page)
 383 {
 384         struct page_collect *pcol = data;
 385         struct inode *inode = pcol->inode;
 386         struct exofs_i_info *oi = exofs_i(inode);
 387         loff_t i_size = i_size_read(inode);
 388         pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 389         size_t len;
 390         int ret;
 391
 392         /* FIXME: Just for debugging, will be removed */
 393         if (PageUptodate(page))
 394                 EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino,
 395                           page->index);
 396
 397         pcol->that_locked_page = page;
 398
 399         if (page->index < end_index)
 400                 len = PAGE_CACHE_SIZE;
 401         else if (page->index == end_index)
 402                 len = i_size & ~PAGE_CACHE_MASK;
 403         else
 404                 len = 0;
 405
 406         if (!len || !obj_created(oi)) {
 407                 /* this will be out of bounds, or doesn't exist yet.
 408                  * Current page is cleared and the request is split
 409                  */
 410                 clear_highpage(page);
 411
 412                 SetPageUptodate(page);
 413                 if (PageError(page))
 414                         ClearPageError(page);
 415
 416                 if (!pcol->read_4_write)
 417                         unlock_page(page);
 418                 EXOFS_DBGMSG("readpage_strip(0x%lx) empty page len=%zx "
 419                              "read_4_write=%d index=0x%lx end_index=0x%lx "
 420                              "splitting\n", inode->i_ino, len,
 421                              pcol->read_4_write, page->index, end_index);
 422
 423                 return read_exec(pcol);
 424         }
 425
 426 try_again:
 427
 428         if (unlikely(pcol->pg_first == -1)) {
 429                 pcol->pg_first = page->index;
 430         } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
 431                    page->index)) {
 432                 /* Discontinuity detected, split the request */
 433                 ret = read_exec(pcol);
 434                 if (unlikely(ret))
 435                         goto fail;
 436                 goto try_again;
 437         }
 438
 439         if (!pcol->pages) {
 440                 ret = pcol_try_alloc(pcol);
 441                 if (unlikely(ret))
 442                         goto fail;
 443         }
 444
 445         if (len != PAGE_CACHE_SIZE)
 446                 zero_user(page, len, PAGE_CACHE_SIZE - len);
 447
 448         EXOFS_DBGMSG2("    readpage_strip(0x%lx, 0x%lx) len=0x%zx\n",
 449                      inode->i_ino, page->index, len);
 450
 451         ret = pcol_add_page(pcol, page, len);
 452         if (ret) {
 453                 EXOFS_DBGMSG2("Failed pcol_add_page pages[i]=%p "
 454                           "this_len=0x%zx nr_pages=%u length=0x%lx\n",
 455                           page, len, pcol->nr_pages, pcol->length);
 456
 457                 /* split the request, and start again with current page */
 458                 ret = read_exec(pcol);
 459                 if (unlikely(ret))
 460                         goto fail;
 461
 462                 goto try_again;
 463         }
 464
 465         return 0;
 466
 467 fail:
 468         /* SetPageError(page); ??? */
 469         unlock_page(page);
 470         return ret;
 471 }
 472
 473 static int exofs_readpages(struct file *file, struct address_space *mapping,
 474                            struct list_head *pages, unsigned nr_pages)
 475 {
 476         struct page_collect pcol;
 477         int ret;
 478
 479         _pcol_init(&pcol, nr_pages, mapping->host);
 480
 481         ret = read_cache_pages(mapping, pages, readpage_strip, &pcol);
 482         if (ret) {
 483                 EXOFS_ERR("read_cache_pages => %d\n", ret);
 484                 return ret;
 485         }
 486
 487         ret = read_exec(&pcol);
 488         if (unlikely(ret))
 489                 return ret;
 490
 491         return read_exec(&pcol);
 492 }
 493
 494 static int _readpage(struct page *page, bool read_4_write)
 495 {
 496         struct page_collect pcol;
 497         int ret;
 498
 499         _pcol_init(&pcol, 1, page->mapping->host);
 500
 501         pcol.read_4_write = read_4_write;
 502         ret = readpage_strip(&pcol, page);
 503         if (ret) {
 504                 EXOFS_ERR("_readpage => %d\n", ret);
 505                 return ret;
 506         }
 507
 508         return read_exec(&pcol);
 509 }
 510
 511 /*
 512  * We don't need the file
 513  */
 514 static int exofs_readpage(struct file *file, struct page *page)
 515 {
 516         return _readpage(page, false);
 517 }
 518
 519 /* Callback for osd_write. All writes are asynchronous */
 520 static void writepages_done(struct ore_io_state *ios, void *p)
 521 {
 522         struct page_collect *pcol = p;
 523         int i;
 524         u64  good_bytes;
 525         u64  length = 0;
 526         int ret = ore_check_io(ios, NULL);
 527
 528         atomic_dec(&pcol->sbi->s_curr_pending);
 529
 530         if (likely(!ret)) {
 531                 good_bytes = pcol->length;
 532                 ret = PAGE_WAS_NOT_IN_IO;
 533         } else {
 534                 good_bytes = 0;
 535         }
 536
 537         EXOFS_DBGMSG2("writepages_done(0x%lx) good_bytes=0x%llx"
 538                      " length=0x%lx nr_pages=%u\n",
 539                      pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 540                      pcol->nr_pages);
 541
 542         for (i = 0; i < pcol->nr_pages; i++) {
 543                 struct page *page = pcol->pages[i];
 544                 struct inode *inode = page->mapping->host;
 545                 int page_stat;
 546
 547                 if (inode != pcol->inode)
 548                         continue; /* osd might add more pages to a bio */
 549
 550                 if (likely(length < good_bytes))
 551                         page_stat = 0;
 552                 else
 553                         page_stat = ret;
 554
 555                 update_write_page(page, page_stat);
 556                 unlock_page(page);
 557                 EXOFS_DBGMSG2("    writepages_done(0x%lx, 0x%lx) status=%d\n",
 558                              inode->i_ino, page->index, page_stat);
 559
 560                 length += PAGE_SIZE;
 561         }
 562
 563         pcol_free(pcol);
 564         kfree(pcol);
 565         EXOFS_DBGMSG2("writepages_done END\n");
 566 }
 567
 568 static struct page *__r4w_get_page(void *priv, u64 offset, bool *uptodate)
 569 {
 570         struct page_collect *pcol = priv;
 571         pgoff_t index = offset / PAGE_SIZE;
 572
 573         if (!pcol->that_locked_page ||
 574             (pcol->that_locked_page->index != index)) {
 575                 struct page *page = find_get_page(pcol->inode->i_mapping, index);
 576
 577                 if (!page) {
 578                         page = find_or_create_page(pcol->inode->i_mapping,
 579                                                    index, GFP_NOFS);
 580                         if (unlikely(!page)) {
 581                                 EXOFS_DBGMSG("grab_cache_page Failed "
 582                                         "index=0x%llx\n", _LLU(index));
 583                                 return NULL;
 584                         }
 585                         unlock_page(page);
 586                 }
 587                 if (PageDirty(page) || PageWriteback(page))
 588                         *uptodate = true;
 589                 else
 590                         *uptodate = PageUptodate(page);
 591                 EXOFS_DBGMSG("index=0x%lx uptodate=%d\n", index, *uptodate);
 592                 return page;
 593         } else {
 594                 EXOFS_DBGMSG("YES that_locked_page index=0x%lx\n",
 595                              pcol->that_locked_page->index);
 596                 *uptodate = true;
 597                 return pcol->that_locked_page;
 598         }
 599 }
 600
 601 static void __r4w_put_page(void *priv, struct page *page)
 602 {
 603         struct page_collect *pcol = priv;
 604
 605         if (pcol->that_locked_page != page) {
 606                 EXOFS_DBGMSG("index=0x%lx\n", page->index);
 607                 page_cache_release(page);
 608                 return;
 609         }
 610         EXOFS_DBGMSG("that_locked_page index=0x%lx\n", page->index);
 611 }
 612
 613 static const struct _ore_r4w_op _r4w_op = {
 614         .get_page = &__r4w_get_page,
 615         .put_page = &__r4w_put_page,
 616 };
 617
 618 static int write_exec(struct page_collect *pcol)
 619 {
 620         struct exofs_i_info *oi = exofs_i(pcol->inode);
 621         struct ore_io_state *ios;
 622         struct page_collect *pcol_copy = NULL;
 623         int ret;
 624
 625         if (!pcol->pages)
 626                 return 0;
 627
 628         BUG_ON(pcol->ios);
 629         ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, false,
 630                                  pcol->pg_first << PAGE_CACHE_SHIFT,
 631                                  pcol->length, &pcol->ios);
 632         if (unlikely(ret))
 633                 goto err;
 634
 635         pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 636         if (!pcol_copy) {
 637                 EXOFS_ERR("write_exec: Failed to kmalloc(pcol)\n");
 638                 ret = -ENOMEM;
 639                 goto err;
 640         }
 641
 642         *pcol_copy = *pcol;
 643
 644         ios = pcol->ios;
 645         ios->pages = pcol_copy->pages;
 646         ios->done = writepages_done;
 647         ios->r4w = &_r4w_op;
 648         ios->private = pcol_copy;
 649
 650         /* pages ownership was passed to pcol_copy */
 651         _pcol_reset(pcol);
 652
 653         ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol);
 654         if (unlikely(ret))
 655                 goto err;
 656
 657         EXOFS_DBGMSG2("write_exec(0x%lx) offset=0x%llx length=0x%llx\n",
 658                 pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length));
 659
 660         ret = ore_write(ios);
 661         if (unlikely(ret)) {
 662                 EXOFS_ERR("write_exec: ore_write() Failed\n");
 663                 goto err;
 664         }
 665
 666         atomic_inc(&pcol->sbi->s_curr_pending);
 667         return 0;
 668
 669 err:
 670         _unlock_pcol_pages(pcol, ret, WRITE);
 671         pcol_free(pcol);
 672         kfree(pcol_copy);
 673
 674         return ret;
 675 }
 676
 677 /* writepage_strip is called either directly from writepage() or by the VFS from
 678  * within write_cache_pages(), to add one more page to be written to storage.
 679  * It will try to collect as many contiguous pages as possible. If a
 680  * discontinuity is encountered or it runs out of resources it will submit the
 681  * previous segment and will start a new collection.
 682  * Eventually caller must submit the last segment if present.
 683  */
 684 static int writepage_strip(struct page *page,
 685                            struct writeback_control *wbc_unused, void *data)
 686 {
 687         struct page_collect *pcol = data;
 688         struct inode *inode = pcol->inode;
 689         struct exofs_i_info *oi = exofs_i(inode);
 690         loff_t i_size = i_size_read(inode);
 691         pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 692         size_t len;
 693         int ret;
 694
 695         BUG_ON(!PageLocked(page));
 696
 697         ret = wait_obj_created(oi);
 698         if (unlikely(ret))
 699                 goto fail;
 700
 701         if (page->index < end_index)
 702                 /* in this case, the page is within the limits of the file */
 703                 len = PAGE_CACHE_SIZE;
 704         else {
 705                 len = i_size & ~PAGE_CACHE_MASK;
 706
 707                 if (page->index > end_index || !len) {
 708                         /* in this case, the page is outside the limits
 709                          * (truncate in progress)
 710                          */
 711                         ret = write_exec(pcol);
 712                         if (unlikely(ret))
 713                                 goto fail;
 714                         if (PageError(page))
 715                                 ClearPageError(page);
 716                         unlock_page(page);
 717                         EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) "
 718                                      "outside the limits\n",
 719                                      inode->i_ino, page->index);
 720                         return 0;
 721                 }
 722         }
 723
 724 try_again:
 725
 726         if (unlikely(pcol->pg_first == -1)) {
 727                 pcol->pg_first = page->index;
 728         } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
 729                    page->index)) {
 730                 /* Discontinuity detected, split the request */
 731                 ret = write_exec(pcol);
 732                 if (unlikely(ret))
 733                         goto fail;
 734
 735                 EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) Discontinuity\n",
 736                              inode->i_ino, page->index);
 737                 goto try_again;
 738         }
 739
 740         if (!pcol->pages) {
 741                 ret = pcol_try_alloc(pcol);
 742                 if (unlikely(ret))
 743                         goto fail;
 744         }
 745
 746         EXOFS_DBGMSG2("    writepage_strip(0x%lx, 0x%lx) len=0x%zx\n",
 747                      inode->i_ino, page->index, len);
 748
 749         ret = pcol_add_page(pcol, page, len);
 750         if (unlikely(ret)) {
 751                 EXOFS_DBGMSG2("Failed pcol_add_page "
 752                              "nr_pages=%u total_length=0x%lx\n",
 753                              pcol->nr_pages, pcol->length);
 754
 755                 /* split the request, next loop will start again */
 756                 ret = write_exec(pcol);
 757                 if (unlikely(ret)) {
 758                         EXOFS_DBGMSG("write_exec failed => %d", ret);
 759                         goto fail;
 760                 }
 761
 762                 goto try_again;
 763         }
 764
 765         BUG_ON(PageWriteback(page));
 766         set_page_writeback(page);
 767
 768         return 0;
 769
 770 fail:
 771         EXOFS_DBGMSG("Error: writepage_strip(0x%lx, 0x%lx)=>%d\n",
 772                      inode->i_ino, page->index, ret);
 773         set_bit(AS_EIO, &page->mapping->flags);
 774         unlock_page(page);
 775         return ret;
 776 }
 777
 778 static int exofs_writepages(struct address_space *mapping,
 779                        struct writeback_control *wbc)
 780 {
 781         struct page_collect pcol;
 782         long start, end, expected_pages;
 783         int ret;
 784
 785         start = wbc->range_start >> PAGE_CACHE_SHIFT;
 786         end = (wbc->range_end == LLONG_MAX) ?
 787                         start + mapping->nrpages :
 788                         wbc->range_end >> PAGE_CACHE_SHIFT;
 789
 790         if (start || end)
 791                 expected_pages = end - start + 1;
 792         else
 793                 expected_pages = mapping->nrpages;
 794
 795         if (expected_pages < 32L)
 796                 expected_pages = 32L;
 797
 798         EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
 799                      "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n",
 800                      mapping->host->i_ino, wbc->range_start, wbc->range_end,
 801                      mapping->nrpages, start, end, expected_pages);
 802
 803         _pcol_init(&pcol, expected_pages, mapping->host);
 804
 805         ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol);
 806         if (unlikely(ret)) {
 807                 EXOFS_ERR("write_cache_pages => %d\n", ret);
 808                 return ret;
 809         }
 810
 811         ret = write_exec(&pcol);
 812         if (unlikely(ret))
 813                 return ret;
 814
 815         if (wbc->sync_mode == WB_SYNC_ALL) {
 816                 return write_exec(&pcol); /* pump the last reminder */
 817         } else if (pcol.nr_pages) {
 818                 /* not SYNC let the reminder join the next writeout */
 819                 unsigned i;
 820
 821                 for (i = 0; i < pcol.nr_pages; i++) {
 822                         struct page *page = pcol.pages[i];
 823
 824                         end_page_writeback(page);
 825                         set_page_dirty(page);
 826                         unlock_page(page);
 827                 }
 828         }
 829         return 0;
 830 }
 831
 832 /*
 833 static int exofs_writepage(struct page *page, struct writeback_control *wbc)
 834 {
 835         struct page_collect pcol;
 836         int ret;
 837
 838         _pcol_init(&pcol, 1, page->mapping->host);
 839
 840         ret = writepage_strip(page, NULL, &pcol);
 841         if (ret) {
 842                 EXOFS_ERR("exofs_writepage => %d\n", ret);
 843                 return ret;
 844         }
 845
 846         return write_exec(&pcol);
 847 }
 848 */
 849 /* i_mutex held using inode->i_size directly */
 850 static void _write_failed(struct inode *inode, loff_t to)
 851 {
 852         if (to > inode->i_size)
 853                 truncate_pagecache(inode, to, inode->i_size);
 854 }
 855
 856 int exofs_write_begin(struct file *file, struct address_space *mapping,
 857                 loff_t pos, unsigned len, unsigned flags,
 858                 struct page **pagep, void **fsdata)
 859 {
 860         int ret = 0;
 861         struct page *page;
 862
 863         page = *pagep;
 864         if (page == NULL) {
 865                 ret = simple_write_begin(file, mapping, pos, len, flags, pagep,
 866                                          fsdata);
 867                 if (ret) {
 868                         EXOFS_DBGMSG("simple_write_begin failed\n");
 869                         goto out;
 870                 }
 871
 872                 page = *pagep;
 873         }
 874
 875          /* read modify write */
 876         if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
 877                 loff_t i_size = i_size_read(mapping->host);
 878                 pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 879                 size_t rlen;
 880
 881                 if (page->index < end_index)
 882                         rlen = PAGE_CACHE_SIZE;
 883                 else if (page->index == end_index)
 884                         rlen = i_size & ~PAGE_CACHE_MASK;
 885                 else
 886                         rlen = 0;
 887
 888                 if (!rlen) {
 889                         clear_highpage(page);
 890                         SetPageUptodate(page);
 891                         goto out;
 892                 }
 893
 894                 ret = _readpage(page, true);
 895                 if (ret) {
 896                         /*SetPageError was done by _readpage. Is it ok?*/
 897                         unlock_page(page);
 898                         EXOFS_DBGMSG("__readpage failed\n");
 899                 }
 900         }
 901 out:
 902         if (unlikely(ret))
 903                 _write_failed(mapping->host, pos + len);
 904
 905         return ret;
 906 }
 907
 908 static int exofs_write_begin_export(struct file *file,
 909                 struct address_space *mapping,
 910                 loff_t pos, unsigned len, unsigned flags,
 911                 struct page **pagep, void **fsdata)
 912 {
 913         *pagep = NULL;
 914
 915         return exofs_write_begin(file, mapping, pos, len, flags, pagep,
 916                                         fsdata);
 917 }
 918
 919 static int exofs_write_end(struct file *file, struct address_space *mapping,
 920                         loff_t pos, unsigned len, unsigned copied,
 921                         struct page *page, void *fsdata)
 922 {
 923         struct inode *inode = mapping->host;
 924         /* According to comment in simple_write_end i_mutex is held */
 925         loff_t i_size = inode->i_size;
 926         int ret;
 927
 928         ret = simple_write_end(file, mapping,pos, len, copied, page, fsdata);
 929         if (unlikely(ret))
 930                 _write_failed(inode, pos + len);
 931
 932         /* TODO: once simple_write_end marks inode dirty remove */
 933         if (i_size != inode->i_size)
 934                 mark_inode_dirty(inode);
 935         return ret;
 936 }
 937
 938 static int exofs_releasepage(struct page *page, gfp_t gfp)
 939 {
 940         EXOFS_DBGMSG("page 0x%lx\n", page->index);
 941         WARN_ON(1);
 942         return 0;
 943 }
 944
 945 static void exofs_invalidatepage(struct page *page, unsigned long offset)
 946 {
 947         EXOFS_DBGMSG("page 0x%lx offset 0x%lx\n", page->index, offset);
 948         WARN_ON(1);
 949 }
 950
 951 const struct address_space_operations exofs_aops = {
 952         .readpage       = exofs_readpage,
 953         .readpages      = exofs_readpages,
 954         .writepage      = NULL,
 955         .writepages     = exofs_writepages,
 956         .write_begin    = exofs_write_begin_export,
 957         .write_end      = exofs_write_end,
 958         .releasepage    = exofs_releasepage,
 959         .set_page_dirty = __set_page_dirty_nobuffers,
 960         .invalidatepage = exofs_invalidatepage,
 961
 962         /* Not implemented Yet */
 963         .bmap           = NULL, /* TODO: use osd's OSD_ACT_READ_MAP */
 964         .direct_IO      = NULL, /* TODO: Should be trivial to do */
 965
 966         /* With these NULL has special meaning or default is not exported */
 967         .get_xip_mem    = NULL,
 968         .migratepage    = NULL,
 969         .launder_page   = NULL,
 970         .is_partially_uptodate = NULL,
 971         .error_remove_page = NULL,
 972 };
 973
 974 /******************************************************************************
 975  * INODE OPERATIONS
 976  *****************************************************************************/
 977
 978 /*
 979  * Test whether an inode is a fast symlink.
 980  */
 981 static inline int exofs_inode_is_fast_symlink(struct inode *inode)
 982 {
 983         struct exofs_i_info *oi = exofs_i(inode);
 984
 985         return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
 986 }
 987
 988 static int _do_truncate(struct inode *inode, loff_t newsize)
 989 {
 990         struct exofs_i_info *oi = exofs_i(inode);
 991         struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
 992         int ret;
 993
 994         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 995
 996         ret = ore_truncate(&sbi->layout, &oi->oc, (u64)newsize);
 997         if (likely(!ret))
 998                 truncate_setsize(inode, newsize);
 999
1000         EXOFS_DBGMSG("(0x%lx) size=0x%llx ret=>%d\n",
1001                      inode->i_ino, newsize, ret);
1002         return ret;
1003 }
1004
1005 /*
1006  * Set inode attributes - update size attribute on OSD if needed,
1007  *                        otherwise just call generic functions.
1008  */
1009 int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
1010 {
1011         struct inode *inode = dentry->d_inode;
1012         int error;
1013
1014         /* if we are about to modify an object, and it hasn't been
1015          * created yet, wait
1016          */
1017         error = wait_obj_created(exofs_i(inode));
1018         if (unlikely(error))
1019                 return error;
1020
1021         error = setattr_prepare(dentry, iattr);
1022         if (unlikely(error))
1023                 return error;
1024
1025         if ((iattr->ia_valid & ATTR_SIZE) &&
1026             iattr->ia_size != i_size_read(inode)) {
1027                 error = _do_truncate(inode, iattr->ia_size);
1028                 if (unlikely(error))
1029                         return error;
1030         }
1031
1032         setattr_copy(inode, iattr);
1033         mark_inode_dirty(inode);
1034         return 0;
1035 }
1036
1037 static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF(
1038         EXOFS_APAGE_FS_DATA,
1039         EXOFS_ATTR_INODE_FILE_LAYOUT,
1040         0);
1041 static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF(
1042         EXOFS_APAGE_FS_DATA,
1043         EXOFS_ATTR_INODE_DIR_LAYOUT,
1044         0);
1045
1046 /*
1047  * Read the Linux inode info from the OSD, and return it as is. In exofs the
1048  * inode info is in an application specific page/attribute of the osd-object.
1049  */
1050 static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
1051                     struct exofs_fcb *inode)
1052 {
1053         struct exofs_sb_info *sbi = sb->s_fs_info;
1054         struct osd_attr attrs[] = {
1055                 [0] = g_attr_inode_data,
1056                 [1] = g_attr_inode_file_layout,
1057                 [2] = g_attr_inode_dir_layout,
1058         };
1059         struct ore_io_state *ios;
1060         struct exofs_on_disk_inode_layout *layout;
1061         int ret;
1062
1063         ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1064         if (unlikely(ret)) {
1065                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
1066                 return ret;
1067         }
1068
1069         attrs[1].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs);
1070         attrs[2].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs);
1071
1072         ios->in_attr = attrs;
1073         ios->in_attr_len = ARRAY_SIZE(attrs);
1074
1075         ret = ore_read(ios);
1076         if (unlikely(ret)) {
1077                 EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
1078                           _LLU(oi->one_comp.obj.id), ret);
1079                 memset(inode, 0, sizeof(*inode));
1080                 inode->i_mode = 0040000 | (0777 & ~022);
1081                 /* If object is lost on target we might as well enable it's
1082                  * delete.
1083                  */
1084                 if ((ret == -ENOENT) || (ret == -EINVAL))
1085                         ret = 0;
1086                 goto out;
1087         }
1088
1089         ret = extract_attr_from_ios(ios, &attrs[0]);
1090         if (ret) {
1091                 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1092                 goto out;
1093         }
1094         WARN_ON(attrs[0].len != EXOFS_INO_ATTR_SIZE);
1095         memcpy(inode, attrs[0].val_ptr, EXOFS_INO_ATTR_SIZE);
1096
1097         ret = extract_attr_from_ios(ios, &attrs[1]);
1098         if (ret) {
1099                 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1100                 goto out;
1101         }
1102         if (attrs[1].len) {
1103                 layout = attrs[1].val_ptr;
1104                 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
1105                         EXOFS_ERR("%s: unsupported files layout %d\n",
1106                                 __func__, layout->gen_func);
1107                         ret = -ENOTSUPP;
1108                         goto out;
1109                 }
1110         }
1111
1112         ret = extract_attr_from_ios(ios, &attrs[2]);
1113         if (ret) {
1114                 EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1115                 goto out;
1116         }
1117         if (attrs[2].len) {
1118                 layout = attrs[2].val_ptr;
1119                 if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
1120                         EXOFS_ERR("%s: unsupported meta-data layout %d\n",
1121                                 __func__, layout->gen_func);
1122                         ret = -ENOTSUPP;
1123                         goto out;
1124                 }
1125         }
1126
1127 out:
1128         ore_put_io_state(ios);
1129         return ret;
1130 }
1131
1132 static void __oi_init(struct exofs_i_info *oi)
1133 {
1134         init_waitqueue_head(&oi->i_wq);
1135         oi->i_flags = 0;
1136 }
1137 /*
1138  * Fill in an inode read from the OSD and set it up for use
1139  */
1140 struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
1141 {
1142         struct exofs_i_info *oi;
1143         struct exofs_fcb fcb;
1144         struct inode *inode;
1145         int ret;
1146
1147         inode = iget_locked(sb, ino);
1148         if (!inode)
1149                 return ERR_PTR(-ENOMEM);
1150         if (!(inode->i_state & I_NEW))
1151                 return inode;
1152         oi = exofs_i(inode);
1153         __oi_init(oi);
1154         exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info,
1155                          exofs_oi_objno(oi));
1156
1157         /* read the inode from the osd */
1158         ret = exofs_get_inode(sb, oi, &fcb);
1159         if (ret)
1160                 goto bad_inode;
1161
1162         set_obj_created(oi);
1163
1164         /* copy stuff from on-disk struct to in-memory struct */
1165         inode->i_mode = le16_to_cpu(fcb.i_mode);
1166         inode->i_uid = le32_to_cpu(fcb.i_uid);
1167         inode->i_gid = le32_to_cpu(fcb.i_gid);
1168         set_nlink(inode, le16_to_cpu(fcb.i_links_count));
1169         inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
1170         inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
1171         inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
1172         inode->i_ctime.tv_nsec =
1173                 inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
1174         oi->i_commit_size = le64_to_cpu(fcb.i_size);
1175         i_size_write(inode, oi->i_commit_size);
1176         inode->i_blkbits = EXOFS_BLKSHIFT;
1177         inode->i_generation = le32_to_cpu(fcb.i_generation);
1178
1179         oi->i_dir_start_lookup = 0;
1180
1181         if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
1182                 ret = -ESTALE;
1183                 goto bad_inode;
1184         }
1185
1186         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1187                 if (fcb.i_data[0])
1188                         inode->i_rdev =
1189                                 old_decode_dev(le32_to_cpu(fcb.i_data[0]));
1190                 else
1191                         inode->i_rdev =
1192                                 new_decode_dev(le32_to_cpu(fcb.i_data[1]));
1193         } else {
1194                 memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
1195         }
1196
1197         inode->i_mapping->backing_dev_info = sb->s_bdi;
1198         if (S_ISREG(inode->i_mode)) {
1199                 inode->i_op = &exofs_file_inode_operations;
1200                 inode->i_fop = &exofs_file_operations;
1201                 inode->i_mapping->a_ops = &exofs_aops;
1202         } else if (S_ISDIR(inode->i_mode)) {
1203                 inode->i_op = &exofs_dir_inode_operations;
1204                 inode->i_fop = &exofs_dir_operations;
1205                 inode->i_mapping->a_ops = &exofs_aops;
1206         } else if (S_ISLNK(inode->i_mode)) {
1207                 if (exofs_inode_is_fast_symlink(inode))
1208                         inode->i_op = &exofs_fast_symlink_inode_operations;
1209                 else {
1210                         inode->i_op = &exofs_symlink_inode_operations;
1211                         inode->i_mapping->a_ops = &exofs_aops;
1212                 }
1213         } else {
1214                 inode->i_op = &exofs_special_inode_operations;
1215                 if (fcb.i_data[0])
1216                         init_special_inode(inode, inode->i_mode,
1217                            old_decode_dev(le32_to_cpu(fcb.i_data[0])));
1218                 else
1219                         init_special_inode(inode, inode->i_mode,
1220                            new_decode_dev(le32_to_cpu(fcb.i_data[1])));
1221         }
1222
1223         unlock_new_inode(inode);
1224         return inode;
1225
1226 bad_inode:
1227         iget_failed(inode);
1228         return ERR_PTR(ret);
1229 }
1230
1231 int __exofs_wait_obj_created(struct exofs_i_info *oi)
1232 {
1233         if (!obj_created(oi)) {
1234                 EXOFS_DBGMSG("!obj_created\n");
1235                 BUG_ON(!obj_2bcreated(oi));
1236                 wait_event(oi->i_wq, obj_created(oi));
1237                 EXOFS_DBGMSG("wait_event done\n");
1238         }
1239         return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
1240 }
1241
1242 /*
1243  * Callback function from exofs_new_inode().  The important thing is that we
1244  * set the obj_created flag so that other methods know that the object exists on
1245  * the OSD.
1246  */
1247 static void create_done(struct ore_io_state *ios, void *p)
1248 {
1249         struct inode *inode = p;
1250         struct exofs_i_info *oi = exofs_i(inode);
1251         struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1252         int ret;
1253
1254         ret = ore_check_io(ios, NULL);
1255         ore_put_io_state(ios);
1256
1257         atomic_dec(&sbi->s_curr_pending);
1258
1259         if (unlikely(ret)) {
1260                 EXOFS_ERR("object=0x%llx creation failed in pid=0x%llx",
1261                           _LLU(exofs_oi_objno(oi)),
1262                           _LLU(oi->one_comp.obj.partition));
1263                 /*TODO: When FS is corrupted creation can fail, object already
1264                  * exist. Get rid of this asynchronous creation, if exist
1265                  * increment the obj counter and try the next object. Until we
1266                  * succeed. All these dangling objects will be made into lost
1267                  * files by chkfs.exofs
1268                  */
1269         }
1270
1271         set_obj_created(oi);
1272
1273         wake_up(&oi->i_wq);
1274 }
1275
1276 /*
1277  * Set up a new inode and create an object for it on the OSD
1278  */
1279 struct inode *exofs_new_inode(struct inode *dir, int mode)
1280 {
1281         struct super_block *sb = dir->i_sb;
1282         struct exofs_sb_info *sbi = sb->s_fs_info;
1283         struct inode *inode;
1284         struct exofs_i_info *oi;
1285         struct ore_io_state *ios;
1286         int ret;
1287
1288         inode = new_inode(sb);
1289         if (!inode)
1290                 return ERR_PTR(-ENOMEM);
1291
1292         oi = exofs_i(inode);
1293         __oi_init(oi);
1294
1295         set_obj_2bcreated(oi);
1296
1297         inode->i_mapping->backing_dev_info = sb->s_bdi;
1298         inode_init_owner(inode, dir, mode);
1299         inode->i_ino = sbi->s_nextid++;
1300         inode->i_blkbits = EXOFS_BLKSHIFT;
1301         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1302         oi->i_commit_size = inode->i_size = 0;
1303         spin_lock(&sbi->s_next_gen_lock);
1304         inode->i_generation = sbi->s_next_generation++;
1305         spin_unlock(&sbi->s_next_gen_lock);
1306         insert_inode_hash(inode);
1307
1308         exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info,
1309                          exofs_oi_objno(oi));
1310         exofs_sbi_write_stats(sbi); /* Make sure new sbi->s_nextid is on disk */
1311
1312         mark_inode_dirty(inode);
1313
1314         ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1315         if (unlikely(ret)) {
1316                 EXOFS_ERR("exofs_new_inode: ore_get_io_state failed\n");
1317                 return ERR_PTR(ret);
1318         }
1319
1320         ios->done = create_done;
1321         ios->private = inode;
1322
1323         ret = ore_create(ios);
1324         if (ret) {
1325                 ore_put_io_state(ios);
1326                 return ERR_PTR(ret);
1327         }
1328         atomic_inc(&sbi->s_curr_pending);
1329
1330         return inode;
1331 }
1332
1333 /*
1334  * struct to pass two arguments to update_inode's callback
1335  */
1336 struct updatei_args {
1337         struct exofs_sb_info    *sbi;
1338         struct exofs_fcb        fcb;
1339 };
1340
1341 /*
1342  * Callback function from exofs_update_inode().
1343  */
1344 static void updatei_done(struct ore_io_state *ios, void *p)
1345 {
1346         struct updatei_args *args = p;
1347
1348         ore_put_io_state(ios);
1349
1350         atomic_dec(&args->sbi->s_curr_pending);
1351
1352         kfree(args);
1353 }
1354
1355 /*
1356  * Write the inode to the OSD.  Just fill up the struct, and set the attribute
1357  * synchronously or asynchronously depending on the do_sync flag.
1358  */
1359 static int exofs_update_inode(struct inode *inode, int do_sync)
1360 {
1361         struct exofs_i_info *oi = exofs_i(inode);
1362         struct super_block *sb = inode->i_sb;
1363         struct exofs_sb_info *sbi = sb->s_fs_info;
1364         struct ore_io_state *ios;
1365         struct osd_attr attr;
1366         struct exofs_fcb *fcb;
1367         struct updatei_args *args;
1368         int ret;
1369
1370         args = kzalloc(sizeof(*args), GFP_KERNEL);
1371         if (!args) {
1372                 EXOFS_DBGMSG("Failed kzalloc of args\n");
1373                 return -ENOMEM;
1374         }
1375
1376         fcb = &args->fcb;
1377
1378         fcb->i_mode = cpu_to_le16(inode->i_mode);
1379         fcb->i_uid = cpu_to_le32(inode->i_uid);
1380         fcb->i_gid = cpu_to_le32(inode->i_gid);
1381         fcb->i_links_count = cpu_to_le16(inode->i_nlink);
1382         fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
1383         fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
1384         fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
1385         oi->i_commit_size = i_size_read(inode);
1386         fcb->i_size = cpu_to_le64(oi->i_commit_size);
1387         fcb->i_generation = cpu_to_le32(inode->i_generation);
1388
1389         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1390                 if (old_valid_dev(inode->i_rdev)) {
1391                         fcb->i_data[0] =
1392                                 cpu_to_le32(old_encode_dev(inode->i_rdev));
1393                         fcb->i_data[1] = 0;
1394                 } else {
1395                         fcb->i_data[0] = 0;
1396                         fcb->i_data[1] =
1397                                 cpu_to_le32(new_encode_dev(inode->i_rdev));
1398                         fcb->i_data[2] = 0;
1399                 }
1400         } else
1401                 memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
1402
1403         ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1404         if (unlikely(ret)) {
1405                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
1406                 goto free_args;
1407         }
1408
1409         attr = g_attr_inode_data;
1410         attr.val_ptr = fcb;
1411         ios->out_attr_len = 1;
1412         ios->out_attr = &attr;
1413
1414         wait_obj_created(oi);
1415
1416         if (!do_sync) {
1417                 args->sbi = sbi;
1418                 ios->done = updatei_done;
1419                 ios->private = args;
1420         }
1421
1422         ret = ore_write(ios);
1423         if (!do_sync && !ret) {
1424                 atomic_inc(&sbi->s_curr_pending);
1425                 goto out; /* deallocation in updatei_done */
1426         }
1427
1428         ore_put_io_state(ios);
1429 free_args:
1430         kfree(args);
1431 out:
1432         EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n",
1433                      inode->i_ino, do_sync, ret);
1434         return ret;
1435 }
1436
1437 int exofs_write_inode(struct inode *inode, struct writeback_control *wbc)
1438 {
1439         /* FIXME: fix fsync and use wbc->sync_mode == WB_SYNC_ALL */
1440         return exofs_update_inode(inode, 1);
1441 }
1442
1443 /*
1444  * Callback function from exofs_delete_inode() - don't have much cleaning up to
1445  * do.
1446  */
1447 static void delete_done(struct ore_io_state *ios, void *p)
1448 {
1449         struct exofs_sb_info *sbi = p;
1450
1451         ore_put_io_state(ios);
1452
1453         atomic_dec(&sbi->s_curr_pending);
1454 }
1455
1456 /*
1457  * Called when the refcount of an inode reaches zero.  We remove the object
1458  * from the OSD here.  We make sure the object was created before we try and
1459  * delete it.
1460  */
1461 void exofs_evict_inode(struct inode *inode)
1462 {
1463         struct exofs_i_info *oi = exofs_i(inode);
1464         struct super_block *sb = inode->i_sb;
1465         struct exofs_sb_info *sbi = sb->s_fs_info;
1466         struct ore_io_state *ios;
1467         int ret;
1468
1469         truncate_inode_pages(&inode->i_data, 0);
1470
1471         /* TODO: should do better here */
1472         if (inode->i_nlink || is_bad_inode(inode))
1473                 goto no_delete;
1474
1475         inode->i_size = 0;
1476         end_writeback(inode);
1477
1478         /* if we are deleting an obj that hasn't been created yet, wait.
1479          * This also makes sure that create_done cannot be called with an
1480          * already evicted inode.
1481          */
1482         wait_obj_created(oi);
1483         /* ignore the error, attempt a remove anyway */
1484
1485         /* Now Remove the OSD objects */
1486         ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1487         if (unlikely(ret)) {
1488                 EXOFS_ERR("%s: ore_get_io_state failed\n", __func__);
1489                 return;
1490         }
1491
1492         ios->done = delete_done;
1493         ios->private = sbi;
1494
1495         ret = ore_remove(ios);
1496         if (ret) {
1497                 EXOFS_ERR("%s: ore_remove failed\n", __func__);
1498                 ore_put_io_state(ios);
1499                 return;
1500         }
1501         atomic_inc(&sbi->s_curr_pending);
1502
1503         return;
1504
1505 no_delete:
1506         end_writeback(inode);
1507 }