linux/fs/exofs/inode.c
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   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
  40unsigned exofs_max_io_pages(struct ore_layout *layout,
  41                            unsigned expected_pages)
  42{
  43        unsigned pages = min_t(unsigned, expected_pages,
  44                               layout->max_io_length / PAGE_SIZE);
  45
  46        return pages;
  47}
  48
  49struct page_collect {
  50        struct exofs_sb_info *sbi;
  51        struct inode *inode;
  52        unsigned expected_pages;
  53        struct ore_io_state *ios;
  54
  55        struct page **pages;
  56        unsigned alloc_pages;
  57        unsigned nr_pages;
  58        unsigned long length;
  59        loff_t pg_first; /* keep 64bit also in 32-arches */
  60        bool read_4_write; /* This means two things: that the read is sync
  61                            * And the pages should not be unlocked.
  62                            */
  63        struct page *that_locked_page;
  64};
  65
  66static void _pcol_init(struct page_collect *pcol, unsigned expected_pages,
  67                       struct inode *inode)
  68{
  69        struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
  70
  71        pcol->sbi = sbi;
  72        pcol->inode = inode;
  73        pcol->expected_pages = expected_pages;
  74
  75        pcol->ios = NULL;
  76        pcol->pages = NULL;
  77        pcol->alloc_pages = 0;
  78        pcol->nr_pages = 0;
  79        pcol->length = 0;
  80        pcol->pg_first = -1;
  81        pcol->read_4_write = false;
  82        pcol->that_locked_page = NULL;
  83}
  84
  85static void _pcol_reset(struct page_collect *pcol)
  86{
  87        pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
  88
  89        pcol->pages = NULL;
  90        pcol->alloc_pages = 0;
  91        pcol->nr_pages = 0;
  92        pcol->length = 0;
  93        pcol->pg_first = -1;
  94        pcol->ios = NULL;
  95        pcol->that_locked_page = NULL;
  96
  97        /* this is probably the end of the loop but in writes
  98         * it might not end here. don't be left with nothing
  99         */
 100        if (!pcol->expected_pages)
 101                pcol->expected_pages =
 102                                exofs_max_io_pages(&pcol->sbi->layout, ~0);
 103}
 104
 105static int pcol_try_alloc(struct page_collect *pcol)
 106{
 107        unsigned pages;
 108
 109        /* TODO: easily support bio chaining */
 110        pages =  exofs_max_io_pages(&pcol->sbi->layout, pcol->expected_pages);
 111
 112        for (; pages; pages >>= 1) {
 113                pcol->pages = kmalloc(pages * sizeof(struct page *),
 114                                      GFP_KERNEL);
 115                if (likely(pcol->pages)) {
 116                        pcol->alloc_pages = pages;
 117                        return 0;
 118                }
 119        }
 120
 121        EXOFS_ERR("Failed to kmalloc expected_pages=%u\n",
 122                  pcol->expected_pages);
 123        return -ENOMEM;
 124}
 125
 126static void pcol_free(struct page_collect *pcol)
 127{
 128        kfree(pcol->pages);
 129        pcol->pages = NULL;
 130
 131        if (pcol->ios) {
 132                ore_put_io_state(pcol->ios);
 133                pcol->ios = NULL;
 134        }
 135}
 136
 137static int pcol_add_page(struct page_collect *pcol, struct page *page,
 138                         unsigned len)
 139{
 140        if (unlikely(pcol->nr_pages >= pcol->alloc_pages))
 141                return -ENOMEM;
 142
 143        pcol->pages[pcol->nr_pages++] = page;
 144        pcol->length += len;
 145        return 0;
 146}
 147
 148enum {PAGE_WAS_NOT_IN_IO = 17};
 149static int update_read_page(struct page *page, int ret)
 150{
 151        switch (ret) {
 152        case 0:
 153                /* Everything is OK */
 154                SetPageUptodate(page);
 155                if (PageError(page))
 156                        ClearPageError(page);
 157                break;
 158        case -EFAULT:
 159                /* In this case we were trying to read something that wasn't on
 160                 * disk yet - return a page full of zeroes.  This should be OK,
 161                 * because the object should be empty (if there was a write
 162                 * before this read, the read would be waiting with the page
 163                 * locked */
 164                clear_highpage(page);
 165
 166                SetPageUptodate(page);
 167                if (PageError(page))
 168                        ClearPageError(page);
 169                EXOFS_DBGMSG("recovered read error\n");
 170                /* fall through */
 171        case PAGE_WAS_NOT_IN_IO:
 172                ret = 0; /* recovered error */
 173                break;
 174        default:
 175                SetPageError(page);
 176        }
 177        return ret;
 178}
 179
 180static void update_write_page(struct page *page, int ret)
 181{
 182        if (unlikely(ret == PAGE_WAS_NOT_IN_IO))
 183                return; /* don't pass start don't collect $200 */
 184
 185        if (ret) {
 186                mapping_set_error(page->mapping, ret);
 187                SetPageError(page);
 188        }
 189        end_page_writeback(page);
 190}
 191
 192/* Called at the end of reads, to optionally unlock pages and update their
 193 * status.
 194 */
 195static int __readpages_done(struct page_collect *pcol)
 196{
 197        int i;
 198        u64 good_bytes;
 199        u64 length = 0;
 200        int ret = ore_check_io(pcol->ios, NULL);
 201
 202        if (likely(!ret)) {
 203                good_bytes = pcol->length;
 204                ret = PAGE_WAS_NOT_IN_IO;
 205        } else {
 206                good_bytes = 0;
 207        }
 208
 209        EXOFS_DBGMSG2("readpages_done(0x%lx) good_bytes=0x%llx"
 210                     " length=0x%lx nr_pages=%u\n",
 211                     pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 212                     pcol->nr_pages);
 213
 214        for (i = 0; i < pcol->nr_pages; i++) {
 215                struct page *page = pcol->pages[i];
 216                struct inode *inode = page->mapping->host;
 217                int page_stat;
 218
 219                if (inode != pcol->inode)
 220                        continue; /* osd might add more pages at end */
 221
 222                if (likely(length < good_bytes))
 223                        page_stat = 0;
 224                else
 225                        page_stat = ret;
 226
 227                EXOFS_DBGMSG2("    readpages_done(0x%lx, 0x%lx) %s\n",
 228                          inode->i_ino, page->index,
 229                          page_stat ? "bad_bytes" : "good_bytes");
 230
 231                ret = update_read_page(page, page_stat);
 232                if (!pcol->read_4_write)
 233                        unlock_page(page);
 234                length += PAGE_SIZE;
 235        }
 236
 237        pcol_free(pcol);
 238        EXOFS_DBGMSG2("readpages_done END\n");
 239        return ret;
 240}
 241
 242/* callback of async reads */
 243static void readpages_done(struct ore_io_state *ios, void *p)
 244{
 245        struct page_collect *pcol = p;
 246
 247        __readpages_done(pcol);
 248        atomic_dec(&pcol->sbi->s_curr_pending);
 249        kfree(pcol);
 250}
 251
 252static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
 253{
 254        int i;
 255
 256        for (i = 0; i < pcol->nr_pages; i++) {
 257                struct page *page = pcol->pages[i];
 258
 259                if (rw == READ)
 260                        update_read_page(page, ret);
 261                else
 262                        update_write_page(page, ret);
 263
 264                unlock_page(page);
 265        }
 266}
 267
 268static int _maybe_not_all_in_one_io(struct ore_io_state *ios,
 269        struct page_collect *pcol_src, struct page_collect *pcol)
 270{
 271        /* length was wrong or offset was not page aligned */
 272        BUG_ON(pcol_src->nr_pages < ios->nr_pages);
 273
 274        if (pcol_src->nr_pages > ios->nr_pages) {
 275                struct page **src_page;
 276                unsigned pages_less = pcol_src->nr_pages - ios->nr_pages;
 277                unsigned long len_less = pcol_src->length - ios->length;
 278                unsigned i;
 279                int ret;
 280
 281                /* This IO was trimmed */
 282                pcol_src->nr_pages = ios->nr_pages;
 283                pcol_src->length = ios->length;
 284
 285                /* Left over pages are passed to the next io */
 286                pcol->expected_pages += pages_less;
 287                pcol->nr_pages = pages_less;
 288                pcol->length = len_less;
 289                src_page = pcol_src->pages + pcol_src->nr_pages;
 290                pcol->pg_first = (*src_page)->index;
 291
 292                ret = pcol_try_alloc(pcol);
 293                if (unlikely(ret))
 294                        return ret;
 295
 296                for (i = 0; i < pages_less; ++i)
 297                        pcol->pages[i] = *src_page++;
 298
 299                EXOFS_DBGMSG("Length was adjusted nr_pages=0x%x "
 300                        "pages_less=0x%x expected_pages=0x%x "
 301                        "next_offset=0x%llx next_len=0x%lx\n",
 302                        pcol_src->nr_pages, pages_less, pcol->expected_pages,
 303                        pcol->pg_first * PAGE_SIZE, pcol->length);
 304        }
 305        return 0;
 306}
 307
 308static int read_exec(struct page_collect *pcol)
 309{
 310        struct exofs_i_info *oi = exofs_i(pcol->inode);
 311        struct ore_io_state *ios;
 312        struct page_collect *pcol_copy = NULL;
 313        int ret;
 314
 315        if (!pcol->pages)
 316                return 0;
 317
 318        if (!pcol->ios) {
 319                int ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, true,
 320                                             pcol->pg_first << PAGE_CACHE_SHIFT,
 321                                             pcol->length, &pcol->ios);
 322
 323                if (ret)
 324                        return ret;
 325        }
 326
 327        ios = pcol->ios;
 328        ios->pages = pcol->pages;
 329
 330        if (pcol->read_4_write) {
 331                ore_read(pcol->ios);
 332                return __readpages_done(pcol);
 333        }
 334
 335        pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 336        if (!pcol_copy) {
 337                ret = -ENOMEM;
 338                goto err;
 339        }
 340
 341        *pcol_copy = *pcol;
 342        ios->done = readpages_done;
 343        ios->private = pcol_copy;
 344
 345        /* pages ownership was passed to pcol_copy */
 346        _pcol_reset(pcol);
 347
 348        ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol);
 349        if (unlikely(ret))
 350                goto err;
 351
 352        EXOFS_DBGMSG2("read_exec(0x%lx) offset=0x%llx length=0x%llx\n",
 353                pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length));
 354
 355        ret = ore_read(ios);
 356        if (unlikely(ret))
 357                goto err;
 358
 359        atomic_inc(&pcol->sbi->s_curr_pending);
 360
 361        return 0;
 362
 363err:
 364        if (!pcol->read_4_write)
 365                _unlock_pcol_pages(pcol, ret, READ);
 366
 367        pcol_free(pcol);
 368
 369        kfree(pcol_copy);
 370        return ret;
 371}
 372
 373/* readpage_strip is called either directly from readpage() or by the VFS from
 374 * within read_cache_pages(), to add one more page to be read. It will try to
 375 * collect as many contiguous pages as posible. If a discontinuity is
 376 * encountered, or it runs out of resources, it will submit the previous segment
 377 * and will start a new collection. Eventually caller must submit the last
 378 * segment if present.
 379 */
 380static int readpage_strip(void *data, struct page *page)
 381{
 382        struct page_collect *pcol = data;
 383        struct inode *inode = pcol->inode;
 384        struct exofs_i_info *oi = exofs_i(inode);
 385        loff_t i_size = i_size_read(inode);
 386        pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 387        size_t len;
 388        int ret;
 389
 390        BUG_ON(!PageLocked(page));
 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
 426try_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
 467fail:
 468        /* SetPageError(page); ??? */
 469        unlock_page(page);
 470        return ret;
 471}
 472
 473static 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
 494static 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 */
 514static 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 */
 520static 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
 568static 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;
 576                loff_t i_size = i_size_read(pcol->inode);
 577
 578                if (offset >= i_size) {
 579                        *uptodate = true;
 580                        EXOFS_DBGMSG("offset >= i_size index=0x%lx\n", index);
 581                        return ZERO_PAGE(0);
 582                }
 583
 584                page =  find_get_page(pcol->inode->i_mapping, index);
 585                if (!page) {
 586                        page = find_or_create_page(pcol->inode->i_mapping,
 587                                                   index, GFP_NOFS);
 588                        if (unlikely(!page)) {
 589                                EXOFS_DBGMSG("grab_cache_page Failed "
 590                                        "index=0x%llx\n", _LLU(index));
 591                                return NULL;
 592                        }
 593                        unlock_page(page);
 594                }
 595                if (PageDirty(page) || PageWriteback(page))
 596                        *uptodate = true;
 597                else
 598                        *uptodate = PageUptodate(page);
 599                EXOFS_DBGMSG("index=0x%lx uptodate=%d\n", index, *uptodate);
 600                return page;
 601        } else {
 602                EXOFS_DBGMSG("YES that_locked_page index=0x%lx\n",
 603                             pcol->that_locked_page->index);
 604                *uptodate = true;
 605                return pcol->that_locked_page;
 606        }
 607}
 608
 609static void __r4w_put_page(void *priv, struct page *page)
 610{
 611        struct page_collect *pcol = priv;
 612
 613        if ((pcol->that_locked_page != page) && (ZERO_PAGE(0) != page)) {
 614                EXOFS_DBGMSG("index=0x%lx\n", page->index);
 615                page_cache_release(page);
 616                return;
 617        }
 618        EXOFS_DBGMSG("that_locked_page index=0x%lx\n",
 619                     ZERO_PAGE(0) == page ? -1 : page->index);
 620}
 621
 622static const struct _ore_r4w_op _r4w_op = {
 623        .get_page = &__r4w_get_page,
 624        .put_page = &__r4w_put_page,
 625};
 626
 627static int write_exec(struct page_collect *pcol)
 628{
 629        struct exofs_i_info *oi = exofs_i(pcol->inode);
 630        struct ore_io_state *ios;
 631        struct page_collect *pcol_copy = NULL;
 632        int ret;
 633
 634        if (!pcol->pages)
 635                return 0;
 636
 637        BUG_ON(pcol->ios);
 638        ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, false,
 639                                 pcol->pg_first << PAGE_CACHE_SHIFT,
 640                                 pcol->length, &pcol->ios);
 641        if (unlikely(ret))
 642                goto err;
 643
 644        pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 645        if (!pcol_copy) {
 646                EXOFS_ERR("write_exec: Failed to kmalloc(pcol)\n");
 647                ret = -ENOMEM;
 648                goto err;
 649        }
 650
 651        *pcol_copy = *pcol;
 652
 653        ios = pcol->ios;
 654        ios->pages = pcol_copy->pages;
 655        ios->done = writepages_done;
 656        ios->r4w = &_r4w_op;
 657        ios->private = pcol_copy;
 658
 659        /* pages ownership was passed to pcol_copy */
 660        _pcol_reset(pcol);
 661
 662        ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol);
 663        if (unlikely(ret))
 664                goto err;
 665
 666        EXOFS_DBGMSG2("write_exec(0x%lx) offset=0x%llx length=0x%llx\n",
 667                pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length));
 668
 669        ret = ore_write(ios);
 670        if (unlikely(ret)) {
 671                EXOFS_ERR("write_exec: ore_write() Failed\n");
 672                goto err;
 673        }
 674
 675        atomic_inc(&pcol->sbi->s_curr_pending);
 676        return 0;
 677
 678err:
 679        _unlock_pcol_pages(pcol, ret, WRITE);
 680        pcol_free(pcol);
 681        kfree(pcol_copy);
 682
 683        return ret;
 684}
 685
 686/* writepage_strip is called either directly from writepage() or by the VFS from
 687 * within write_cache_pages(), to add one more page to be written to storage.
 688 * It will try to collect as many contiguous pages as possible. If a
 689 * discontinuity is encountered or it runs out of resources it will submit the
 690 * previous segment and will start a new collection.
 691 * Eventually caller must submit the last segment if present.
 692 */
 693static int writepage_strip(struct page *page,
 694                           struct writeback_control *wbc_unused, void *data)
 695{
 696        struct page_collect *pcol = data;
 697        struct inode *inode = pcol->inode;
 698        struct exofs_i_info *oi = exofs_i(inode);
 699        loff_t i_size = i_size_read(inode);
 700        pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 701        size_t len;
 702        int ret;
 703
 704        BUG_ON(!PageLocked(page));
 705
 706        ret = wait_obj_created(oi);
 707        if (unlikely(ret))
 708                goto fail;
 709
 710        if (page->index < end_index)
 711                /* in this case, the page is within the limits of the file */
 712                len = PAGE_CACHE_SIZE;
 713        else {
 714                len = i_size & ~PAGE_CACHE_MASK;
 715
 716                if (page->index > end_index || !len) {
 717                        /* in this case, the page is outside the limits
 718                         * (truncate in progress)
 719                         */
 720                        ret = write_exec(pcol);
 721                        if (unlikely(ret))
 722                                goto fail;
 723                        if (PageError(page))
 724                                ClearPageError(page);
 725                        unlock_page(page);
 726                        EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) "
 727                                     "outside the limits\n",
 728                                     inode->i_ino, page->index);
 729                        return 0;
 730                }
 731        }
 732
 733try_again:
 734
 735        if (unlikely(pcol->pg_first == -1)) {
 736                pcol->pg_first = page->index;
 737        } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
 738                   page->index)) {
 739                /* Discontinuity detected, split the request */
 740                ret = write_exec(pcol);
 741                if (unlikely(ret))
 742                        goto fail;
 743
 744                EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) Discontinuity\n",
 745                             inode->i_ino, page->index);
 746                goto try_again;
 747        }
 748
 749        if (!pcol->pages) {
 750                ret = pcol_try_alloc(pcol);
 751                if (unlikely(ret))
 752                        goto fail;
 753        }
 754
 755        EXOFS_DBGMSG2("    writepage_strip(0x%lx, 0x%lx) len=0x%zx\n",
 756                     inode->i_ino, page->index, len);
 757
 758        ret = pcol_add_page(pcol, page, len);
 759        if (unlikely(ret)) {
 760                EXOFS_DBGMSG2("Failed pcol_add_page "
 761                             "nr_pages=%u total_length=0x%lx\n",
 762                             pcol->nr_pages, pcol->length);
 763
 764                /* split the request, next loop will start again */
 765                ret = write_exec(pcol);
 766                if (unlikely(ret)) {
 767                        EXOFS_DBGMSG("write_exec failed => %d", ret);
 768                        goto fail;
 769                }
 770
 771                goto try_again;
 772        }
 773
 774        BUG_ON(PageWriteback(page));
 775        set_page_writeback(page);
 776
 777        return 0;
 778
 779fail:
 780        EXOFS_DBGMSG("Error: writepage_strip(0x%lx, 0x%lx)=>%d\n",
 781                     inode->i_ino, page->index, ret);
 782        set_bit(AS_EIO, &page->mapping->flags);
 783        unlock_page(page);
 784        return ret;
 785}
 786
 787static int exofs_writepages(struct address_space *mapping,
 788                       struct writeback_control *wbc)
 789{
 790        struct page_collect pcol;
 791        long start, end, expected_pages;
 792        int ret;
 793
 794        start = wbc->range_start >> PAGE_CACHE_SHIFT;
 795        end = (wbc->range_end == LLONG_MAX) ?
 796                        start + mapping->nrpages :
 797                        wbc->range_end >> PAGE_CACHE_SHIFT;
 798
 799        if (start || end)
 800                expected_pages = end - start + 1;
 801        else
 802                expected_pages = mapping->nrpages;
 803
 804        if (expected_pages < 32L)
 805                expected_pages = 32L;
 806
 807        EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx "
 808                     "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n",
 809                     mapping->host->i_ino, wbc->range_start, wbc->range_end,
 810                     mapping->nrpages, start, end, expected_pages);
 811
 812        _pcol_init(&pcol, expected_pages, mapping->host);
 813
 814        ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol);
 815        if (unlikely(ret)) {
 816                EXOFS_ERR("write_cache_pages => %d\n", ret);
 817                return ret;
 818        }
 819
 820        ret = write_exec(&pcol);
 821        if (unlikely(ret))
 822                return ret;
 823
 824        if (wbc->sync_mode == WB_SYNC_ALL) {
 825                return write_exec(&pcol); /* pump the last reminder */
 826        } else if (pcol.nr_pages) {
 827                /* not SYNC let the reminder join the next writeout */
 828                unsigned i;
 829
 830                for (i = 0; i < pcol.nr_pages; i++) {
 831                        struct page *page = pcol.pages[i];
 832
 833                        end_page_writeback(page);
 834                        set_page_dirty(page);
 835                        unlock_page(page);
 836                }
 837        }
 838        return 0;
 839}
 840
 841/*
 842static int exofs_writepage(struct page *page, struct writeback_control *wbc)
 843{
 844        struct page_collect pcol;
 845        int ret;
 846
 847        _pcol_init(&pcol, 1, page->mapping->host);
 848
 849        ret = writepage_strip(page, NULL, &pcol);
 850        if (ret) {
 851                EXOFS_ERR("exofs_writepage => %d\n", ret);
 852                return ret;
 853        }
 854
 855        return write_exec(&pcol);
 856}
 857*/
 858/* i_mutex held using inode->i_size directly */
 859static void _write_failed(struct inode *inode, loff_t to)
 860{
 861        if (to > inode->i_size)
 862                truncate_pagecache(inode, to, inode->i_size);
 863}
 864
 865int exofs_write_begin(struct file *file, struct address_space *mapping,
 866                loff_t pos, unsigned len, unsigned flags,
 867                struct page **pagep, void **fsdata)
 868{
 869        int ret = 0;
 870        struct page *page;
 871
 872        page = *pagep;
 873        if (page == NULL) {
 874                ret = simple_write_begin(file, mapping, pos, len, flags, pagep,
 875                                         fsdata);
 876                if (ret) {
 877                        EXOFS_DBGMSG("simple_write_begin failed\n");
 878                        goto out;
 879                }
 880
 881                page = *pagep;
 882        }
 883
 884         /* read modify write */
 885        if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
 886                loff_t i_size = i_size_read(mapping->host);
 887                pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 888                size_t rlen;
 889
 890                if (page->index < end_index)
 891                        rlen = PAGE_CACHE_SIZE;
 892                else if (page->index == end_index)
 893                        rlen = i_size & ~PAGE_CACHE_MASK;
 894                else
 895                        rlen = 0;
 896
 897                if (!rlen) {
 898                        clear_highpage(page);
 899                        SetPageUptodate(page);
 900                        goto out;
 901                }
 902
 903                ret = _readpage(page, true);
 904                if (ret) {
 905                        /*SetPageError was done by _readpage. Is it ok?*/
 906                        unlock_page(page);
 907                        EXOFS_DBGMSG("__readpage failed\n");
 908                }
 909        }
 910out:
 911        if (unlikely(ret))
 912                _write_failed(mapping->host, pos + len);
 913
 914        return ret;
 915}
 916
 917static int exofs_write_begin_export(struct file *file,
 918                struct address_space *mapping,
 919                loff_t pos, unsigned len, unsigned flags,
 920                struct page **pagep, void **fsdata)
 921{
 922        *pagep = NULL;
 923
 924        return exofs_write_begin(file, mapping, pos, len, flags, pagep,
 925                                        fsdata);
 926}
 927
 928static int exofs_write_end(struct file *file, struct address_space *mapping,
 929                        loff_t pos, unsigned len, unsigned copied,
 930                        struct page *page, void *fsdata)
 931{
 932        struct inode *inode = mapping->host;
 933        /* According to comment in simple_write_end i_mutex is held */
 934        loff_t i_size = inode->i_size;
 935        int ret;
 936
 937        ret = simple_write_end(file, mapping,pos, len, copied, page, fsdata);
 938        if (unlikely(ret))
 939                _write_failed(inode, pos + len);
 940
 941        /* TODO: once simple_write_end marks inode dirty remove */
 942        if (i_size != inode->i_size)
 943                mark_inode_dirty(inode);
 944        return ret;
 945}
 946
 947static int exofs_releasepage(struct page *page, gfp_t gfp)
 948{
 949        EXOFS_DBGMSG("page 0x%lx\n", page->index);
 950        WARN_ON(1);
 951        return 0;
 952}
 953
 954static void exofs_invalidatepage(struct page *page, unsigned long offset)
 955{
 956        EXOFS_DBGMSG("page 0x%lx offset 0x%lx\n", page->index, offset);
 957        WARN_ON(1);
 958}
 959
 960const struct address_space_operations exofs_aops = {
 961        .readpage       = exofs_readpage,
 962        .readpages      = exofs_readpages,
 963        .writepage      = NULL,
 964        .writepages     = exofs_writepages,
 965        .write_begin    = exofs_write_begin_export,
 966        .write_end      = exofs_write_end,
 967        .releasepage    = exofs_releasepage,
 968        .set_page_dirty = __set_page_dirty_nobuffers,
 969        .invalidatepage = exofs_invalidatepage,
 970
 971        /* Not implemented Yet */
 972        .bmap           = NULL, /* TODO: use osd's OSD_ACT_READ_MAP */
 973        .direct_IO      = NULL, /* TODO: Should be trivial to do */
 974
 975        /* With these NULL has special meaning or default is not exported */
 976        .get_xip_mem    = NULL,
 977        .migratepage    = NULL,
 978        .launder_page   = NULL,
 979        .is_partially_uptodate = NULL,
 980        .error_remove_page = NULL,
 981};
 982
 983/******************************************************************************
 984 * INODE OPERATIONS
 985 *****************************************************************************/
 986
 987/*
 988 * Test whether an inode is a fast symlink.
 989 */
 990static inline int exofs_inode_is_fast_symlink(struct inode *inode)
 991{
 992        struct exofs_i_info *oi = exofs_i(inode);
 993
 994        return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
 995}
 996
 997static int _do_truncate(struct inode *inode, loff_t newsize)
 998{
 999        struct exofs_i_info *oi = exofs_i(inode);
1000        struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1001        int ret;
1002
1003        inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1004
1005        ret = ore_truncate(&sbi->layout, &oi->oc, (u64)newsize);
1006        if (likely(!ret))
1007                truncate_setsize(inode, newsize);
1008
1009        EXOFS_DBGMSG("(0x%lx) size=0x%llx ret=>%d\n",
1010                     inode->i_ino, newsize, ret);
1011        return ret;
1012}
1013
1014/*
1015 * Set inode attributes - update size attribute on OSD if needed,
1016 *                        otherwise just call generic functions.
1017 */
1018int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
1019{
1020        struct inode *inode = dentry->d_inode;
1021        int error;
1022
1023        /* if we are about to modify an object, and it hasn't been
1024         * created yet, wait
1025         */
1026        error = wait_obj_created(exofs_i(inode));
1027        if (unlikely(error))
1028                return error;
1029
1030        error = inode_change_ok(inode, iattr);
1031        if (unlikely(error))
1032                return error;
1033
1034        if ((iattr->ia_valid & ATTR_SIZE) &&
1035            iattr->ia_size != i_size_read(inode)) {
1036                error = _do_truncate(inode, iattr->ia_size);
1037                if (unlikely(error))
1038                        return error;
1039        }
1040
1041        setattr_copy(inode, iattr);
1042        mark_inode_dirty(inode);
1043        return 0;
1044}
1045
1046static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF(
1047        EXOFS_APAGE_FS_DATA,
1048        EXOFS_ATTR_INODE_FILE_LAYOUT,
1049        0);
1050static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF(
1051        EXOFS_APAGE_FS_DATA,
1052        EXOFS_ATTR_INODE_DIR_LAYOUT,
1053        0);
1054
1055/*
1056 * Read the Linux inode info from the OSD, and return it as is. In exofs the
1057 * inode info is in an application specific page/attribute of the osd-object.
1058 */
1059static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
1060                    struct exofs_fcb *inode)
1061{
1062        struct exofs_sb_info *sbi = sb->s_fs_info;
1063        struct osd_attr attrs[] = {
1064                [0] = g_attr_inode_data,
1065                [1] = g_attr_inode_file_layout,
1066                [2] = g_attr_inode_dir_layout,
1067        };
1068        struct ore_io_state *ios;
1069        struct exofs_on_disk_inode_layout *layout;
1070        int ret;
1071
1072        ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1073        if (unlikely(ret)) {
1074                EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
1075                return ret;
1076        }
1077
1078        attrs[1].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs);
1079        attrs[2].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs);
1080
1081        ios->in_attr = attrs;
1082        ios->in_attr_len = ARRAY_SIZE(attrs);
1083
1084        ret = ore_read(ios);
1085        if (unlikely(ret)) {
1086                EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n",
1087                          _LLU(oi->one_comp.obj.id), ret);
1088                memset(inode, 0, sizeof(*inode));
1089                inode->i_mode = 0040000 | (0777 & ~022);
1090                /* If object is lost on target we might as well enable it's
1091                 * delete.
1092                 */
1093                if ((ret == -ENOENT) || (ret == -EINVAL))
1094                        ret = 0;
1095                goto out;
1096        }
1097
1098        ret = extract_attr_from_ios(ios, &attrs[0]);
1099        if (ret) {
1100                EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1101                goto out;
1102        }
1103        WARN_ON(attrs[0].len != EXOFS_INO_ATTR_SIZE);
1104        memcpy(inode, attrs[0].val_ptr, EXOFS_INO_ATTR_SIZE);
1105
1106        ret = extract_attr_from_ios(ios, &attrs[1]);
1107        if (ret) {
1108                EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1109                goto out;
1110        }
1111        if (attrs[1].len) {
1112                layout = attrs[1].val_ptr;
1113                if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
1114                        EXOFS_ERR("%s: unsupported files layout %d\n",
1115                                __func__, layout->gen_func);
1116                        ret = -ENOTSUPP;
1117                        goto out;
1118                }
1119        }
1120
1121        ret = extract_attr_from_ios(ios, &attrs[2]);
1122        if (ret) {
1123                EXOFS_ERR("%s: extract_attr of inode_data failed\n", __func__);
1124                goto out;
1125        }
1126        if (attrs[2].len) {
1127                layout = attrs[2].val_ptr;
1128                if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) {
1129                        EXOFS_ERR("%s: unsupported meta-data layout %d\n",
1130                                __func__, layout->gen_func);
1131                        ret = -ENOTSUPP;
1132                        goto out;
1133                }
1134        }
1135
1136out:
1137        ore_put_io_state(ios);
1138        return ret;
1139}
1140
1141static void __oi_init(struct exofs_i_info *oi)
1142{
1143        init_waitqueue_head(&oi->i_wq);
1144        oi->i_flags = 0;
1145}
1146/*
1147 * Fill in an inode read from the OSD and set it up for use
1148 */
1149struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
1150{
1151        struct exofs_i_info *oi;
1152        struct exofs_fcb fcb;
1153        struct inode *inode;
1154        int ret;
1155
1156        inode = iget_locked(sb, ino);
1157        if (!inode)
1158                return ERR_PTR(-ENOMEM);
1159        if (!(inode->i_state & I_NEW))
1160                return inode;
1161        oi = exofs_i(inode);
1162        __oi_init(oi);
1163        exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info,
1164                         exofs_oi_objno(oi));
1165
1166        /* read the inode from the osd */
1167        ret = exofs_get_inode(sb, oi, &fcb);
1168        if (ret)
1169                goto bad_inode;
1170
1171        set_obj_created(oi);
1172
1173        /* copy stuff from on-disk struct to in-memory struct */
1174        inode->i_mode = le16_to_cpu(fcb.i_mode);
1175        inode->i_uid = le32_to_cpu(fcb.i_uid);
1176        inode->i_gid = le32_to_cpu(fcb.i_gid);
1177        set_nlink(inode, le16_to_cpu(fcb.i_links_count));
1178        inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
1179        inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
1180        inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
1181        inode->i_ctime.tv_nsec =
1182                inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
1183        oi->i_commit_size = le64_to_cpu(fcb.i_size);
1184        i_size_write(inode, oi->i_commit_size);
1185        inode->i_blkbits = EXOFS_BLKSHIFT;
1186        inode->i_generation = le32_to_cpu(fcb.i_generation);
1187
1188        oi->i_dir_start_lookup = 0;
1189
1190        if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
1191                ret = -ESTALE;
1192                goto bad_inode;
1193        }
1194
1195        if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1196                if (fcb.i_data[0])
1197                        inode->i_rdev =
1198                                old_decode_dev(le32_to_cpu(fcb.i_data[0]));
1199                else
1200                        inode->i_rdev =
1201                                new_decode_dev(le32_to_cpu(fcb.i_data[1]));
1202        } else {
1203                memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
1204        }
1205
1206        inode->i_mapping->backing_dev_info = sb->s_bdi;
1207        if (S_ISREG(inode->i_mode)) {
1208                inode->i_op = &exofs_file_inode_operations;
1209                inode->i_fop = &exofs_file_operations;
1210                inode->i_mapping->a_ops = &exofs_aops;
1211        } else if (S_ISDIR(inode->i_mode)) {
1212                inode->i_op = &exofs_dir_inode_operations;
1213                inode->i_fop = &exofs_dir_operations;
1214                inode->i_mapping->a_ops = &exofs_aops;
1215        } else if (S_ISLNK(inode->i_mode)) {
1216                if (exofs_inode_is_fast_symlink(inode))
1217                        inode->i_op = &exofs_fast_symlink_inode_operations;
1218                else {
1219                        inode->i_op = &exofs_symlink_inode_operations;
1220                        inode->i_mapping->a_ops = &exofs_aops;
1221                }
1222        } else {
1223                inode->i_op = &exofs_special_inode_operations;
1224                if (fcb.i_data[0])
1225                        init_special_inode(inode, inode->i_mode,
1226                           old_decode_dev(le32_to_cpu(fcb.i_data[0])));
1227                else
1228                        init_special_inode(inode, inode->i_mode,
1229                           new_decode_dev(le32_to_cpu(fcb.i_data[1])));
1230        }
1231
1232        unlock_new_inode(inode);
1233        return inode;
1234
1235bad_inode:
1236        iget_failed(inode);
1237        return ERR_PTR(ret);
1238}
1239
1240int __exofs_wait_obj_created(struct exofs_i_info *oi)
1241{
1242        if (!obj_created(oi)) {
1243                EXOFS_DBGMSG("!obj_created\n");
1244                BUG_ON(!obj_2bcreated(oi));
1245                wait_event(oi->i_wq, obj_created(oi));
1246                EXOFS_DBGMSG("wait_event done\n");
1247        }
1248        return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
1249}
1250
1251/*
1252 * Callback function from exofs_new_inode().  The important thing is that we
1253 * set the obj_created flag so that other methods know that the object exists on
1254 * the OSD.
1255 */
1256static void create_done(struct ore_io_state *ios, void *p)
1257{
1258        struct inode *inode = p;
1259        struct exofs_i_info *oi = exofs_i(inode);
1260        struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1261        int ret;
1262
1263        ret = ore_check_io(ios, NULL);
1264        ore_put_io_state(ios);
1265
1266        atomic_dec(&sbi->s_curr_pending);
1267
1268        if (unlikely(ret)) {
1269                EXOFS_ERR("object=0x%llx creation failed in pid=0x%llx",
1270                          _LLU(exofs_oi_objno(oi)),
1271                          _LLU(oi->one_comp.obj.partition));
1272                /*TODO: When FS is corrupted creation can fail, object already
1273                 * exist. Get rid of this asynchronous creation, if exist
1274                 * increment the obj counter and try the next object. Until we
1275                 * succeed. All these dangling objects will be made into lost
1276                 * files by chkfs.exofs
1277                 */
1278        }
1279
1280        set_obj_created(oi);
1281
1282        wake_up(&oi->i_wq);
1283}
1284
1285/*
1286 * Set up a new inode and create an object for it on the OSD
1287 */
1288struct inode *exofs_new_inode(struct inode *dir, umode_t mode)
1289{
1290        struct super_block *sb = dir->i_sb;
1291        struct exofs_sb_info *sbi = sb->s_fs_info;
1292        struct inode *inode;
1293        struct exofs_i_info *oi;
1294        struct ore_io_state *ios;
1295        int ret;
1296
1297        inode = new_inode(sb);
1298        if (!inode)
1299                return ERR_PTR(-ENOMEM);
1300
1301        oi = exofs_i(inode);
1302        __oi_init(oi);
1303
1304        set_obj_2bcreated(oi);
1305
1306        inode->i_mapping->backing_dev_info = sb->s_bdi;
1307        inode_init_owner(inode, dir, mode);
1308        inode->i_ino = sbi->s_nextid++;
1309        inode->i_blkbits = EXOFS_BLKSHIFT;
1310        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1311        oi->i_commit_size = inode->i_size = 0;
1312        spin_lock(&sbi->s_next_gen_lock);
1313        inode->i_generation = sbi->s_next_generation++;
1314        spin_unlock(&sbi->s_next_gen_lock);
1315        insert_inode_hash(inode);
1316
1317        exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info,
1318                         exofs_oi_objno(oi));
1319        exofs_sbi_write_stats(sbi); /* Make sure new sbi->s_nextid is on disk */
1320
1321        mark_inode_dirty(inode);
1322
1323        ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1324        if (unlikely(ret)) {
1325                EXOFS_ERR("exofs_new_inode: ore_get_io_state failed\n");
1326                return ERR_PTR(ret);
1327        }
1328
1329        ios->done = create_done;
1330        ios->private = inode;
1331
1332        ret = ore_create(ios);
1333        if (ret) {
1334                ore_put_io_state(ios);
1335                return ERR_PTR(ret);
1336        }
1337        atomic_inc(&sbi->s_curr_pending);
1338
1339        return inode;
1340}
1341
1342/*
1343 * struct to pass two arguments to update_inode's callback
1344 */
1345struct updatei_args {
1346        struct exofs_sb_info    *sbi;
1347        struct exofs_fcb        fcb;
1348};
1349
1350/*
1351 * Callback function from exofs_update_inode().
1352 */
1353static void updatei_done(struct ore_io_state *ios, void *p)
1354{
1355        struct updatei_args *args = p;
1356
1357        ore_put_io_state(ios);
1358
1359        atomic_dec(&args->sbi->s_curr_pending);
1360
1361        kfree(args);
1362}
1363
1364/*
1365 * Write the inode to the OSD.  Just fill up the struct, and set the attribute
1366 * synchronously or asynchronously depending on the do_sync flag.
1367 */
1368static int exofs_update_inode(struct inode *inode, int do_sync)
1369{
1370        struct exofs_i_info *oi = exofs_i(inode);
1371        struct super_block *sb = inode->i_sb;
1372        struct exofs_sb_info *sbi = sb->s_fs_info;
1373        struct ore_io_state *ios;
1374        struct osd_attr attr;
1375        struct exofs_fcb *fcb;
1376        struct updatei_args *args;
1377        int ret;
1378
1379        args = kzalloc(sizeof(*args), GFP_KERNEL);
1380        if (!args) {
1381                EXOFS_DBGMSG("Failed kzalloc of args\n");
1382                return -ENOMEM;
1383        }
1384
1385        fcb = &args->fcb;
1386
1387        fcb->i_mode = cpu_to_le16(inode->i_mode);
1388        fcb->i_uid = cpu_to_le32(inode->i_uid);
1389        fcb->i_gid = cpu_to_le32(inode->i_gid);
1390        fcb->i_links_count = cpu_to_le16(inode->i_nlink);
1391        fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
1392        fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
1393        fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
1394        oi->i_commit_size = i_size_read(inode);
1395        fcb->i_size = cpu_to_le64(oi->i_commit_size);
1396        fcb->i_generation = cpu_to_le32(inode->i_generation);
1397
1398        if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1399                if (old_valid_dev(inode->i_rdev)) {
1400                        fcb->i_data[0] =
1401                                cpu_to_le32(old_encode_dev(inode->i_rdev));
1402                        fcb->i_data[1] = 0;
1403                } else {
1404                        fcb->i_data[0] = 0;
1405                        fcb->i_data[1] =
1406                                cpu_to_le32(new_encode_dev(inode->i_rdev));
1407                        fcb->i_data[2] = 0;
1408                }
1409        } else
1410                memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
1411
1412        ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1413        if (unlikely(ret)) {
1414                EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
1415                goto free_args;
1416        }
1417
1418        attr = g_attr_inode_data;
1419        attr.val_ptr = fcb;
1420        ios->out_attr_len = 1;
1421        ios->out_attr = &attr;
1422
1423        wait_obj_created(oi);
1424
1425        if (!do_sync) {
1426                args->sbi = sbi;
1427                ios->done = updatei_done;
1428                ios->private = args;
1429        }
1430
1431        ret = ore_write(ios);
1432        if (!do_sync && !ret) {
1433                atomic_inc(&sbi->s_curr_pending);
1434                goto out; /* deallocation in updatei_done */
1435        }
1436
1437        ore_put_io_state(ios);
1438free_args:
1439        kfree(args);
1440out:
1441        EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n",
1442                     inode->i_ino, do_sync, ret);
1443        return ret;
1444}
1445
1446int exofs_write_inode(struct inode *inode, struct writeback_control *wbc)
1447{
1448        /* FIXME: fix fsync and use wbc->sync_mode == WB_SYNC_ALL */
1449        return exofs_update_inode(inode, 1);
1450}
1451
1452/*
1453 * Callback function from exofs_delete_inode() - don't have much cleaning up to
1454 * do.
1455 */
1456static void delete_done(struct ore_io_state *ios, void *p)
1457{
1458        struct exofs_sb_info *sbi = p;
1459
1460        ore_put_io_state(ios);
1461
1462        atomic_dec(&sbi->s_curr_pending);
1463}
1464
1465/*
1466 * Called when the refcount of an inode reaches zero.  We remove the object
1467 * from the OSD here.  We make sure the object was created before we try and
1468 * delete it.
1469 */
1470void exofs_evict_inode(struct inode *inode)
1471{
1472        struct exofs_i_info *oi = exofs_i(inode);
1473        struct super_block *sb = inode->i_sb;
1474        struct exofs_sb_info *sbi = sb->s_fs_info;
1475        struct ore_io_state *ios;
1476        int ret;
1477
1478        truncate_inode_pages(&inode->i_data, 0);
1479
1480        /* TODO: should do better here */
1481        if (inode->i_nlink || is_bad_inode(inode))
1482                goto no_delete;
1483
1484        inode->i_size = 0;
1485        clear_inode(inode);
1486
1487        /* if we are deleting an obj that hasn't been created yet, wait.
1488         * This also makes sure that create_done cannot be called with an
1489         * already evicted inode.
1490         */
1491        wait_obj_created(oi);
1492        /* ignore the error, attempt a remove anyway */
1493
1494        /* Now Remove the OSD objects */
1495        ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios);
1496        if (unlikely(ret)) {
1497                EXOFS_ERR("%s: ore_get_io_state failed\n", __func__);
1498                return;
1499        }
1500
1501        ios->done = delete_done;
1502        ios->private = sbi;
1503
1504        ret = ore_remove(ios);
1505        if (ret) {
1506                EXOFS_ERR("%s: ore_remove failed\n", __func__);
1507                ore_put_io_state(ios);
1508                return;
1509        }
1510        atomic_inc(&sbi->s_curr_pending);
1511
1512        return;
1513
1514no_delete:
1515        clear_inode(inode);
1516}
1517
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