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/writeback.h>
  35 #include <linux/buffer_head.h>
  36 #include <scsi/scsi_device.h>
  37
  38 #include "exofs.h"
  39
  40 #ifdef CONFIG_EXOFS_DEBUG
  41 #  define EXOFS_DEBUG_OBJ_ISIZE 1
  42 #endif
  43
  44 struct page_collect {
  45         struct exofs_sb_info *sbi;
  46         struct request_queue *req_q;
  47         struct inode *inode;
  48         unsigned expected_pages;
  49
  50         struct bio *bio;
  51         unsigned nr_pages;
  52         unsigned long length;
  53         loff_t pg_first; /* keep 64bit also in 32-arches */
  54 };
  55
  56 static void _pcol_init(struct page_collect *pcol, unsigned expected_pages,
  57                 struct inode *inode)
  58 {
  59         struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
  60
  61         pcol->sbi = sbi;
  62         pcol->req_q = osd_request_queue(sbi->s_dev);
  63         pcol->inode = inode;
  64         pcol->expected_pages = expected_pages;
  65
  66         pcol->bio = NULL;
  67         pcol->nr_pages = 0;
  68         pcol->length = 0;
  69         pcol->pg_first = -1;
  70
  71         EXOFS_DBGMSG("_pcol_init ino=0x%lx expected_pages=%u\n", inode->i_ino,
  72                      expected_pages);
  73 }
  74
  75 static void _pcol_reset(struct page_collect *pcol)
  76 {
  77         pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
  78
  79         pcol->bio = NULL;
  80         pcol->nr_pages = 0;
  81         pcol->length = 0;
  82         pcol->pg_first = -1;
  83         EXOFS_DBGMSG("_pcol_reset ino=0x%lx expected_pages=%u\n",
  84                      pcol->inode->i_ino, pcol->expected_pages);
  85
  86         /* this is probably the end of the loop but in writes
  87          * it might not end here. don't be left with nothing
  88          */
  89         if (!pcol->expected_pages)
  90                 pcol->expected_pages = 128;
  91 }
  92
  93 static int pcol_try_alloc(struct page_collect *pcol)
  94 {
  95         int pages = min_t(unsigned, pcol->expected_pages, BIO_MAX_PAGES);
  96
  97         for (; pages; pages >>= 1) {
  98                 pcol->bio = bio_alloc(GFP_KERNEL, pages);
  99                 if (likely(pcol->bio))
 100                         return 0;
 101         }
 102
 103         EXOFS_ERR("Failed to kcalloc expected_pages=%u\n",
 104                   pcol->expected_pages);
 105         return -ENOMEM;
 106 }
 107
 108 static void pcol_free(struct page_collect *pcol)
 109 {
 110         bio_put(pcol->bio);
 111         pcol->bio = NULL;
 112 }
 113
 114 static int pcol_add_page(struct page_collect *pcol, struct page *page,
 115                          unsigned len)
 116 {
 117         int added_len = bio_add_pc_page(pcol->req_q, pcol->bio, page, len, 0);
 118         if (unlikely(len != added_len))
 119                 return -ENOMEM;
 120
 121         ++pcol->nr_pages;
 122         pcol->length += len;
 123         return 0;
 124 }
 125
 126 static int update_read_page(struct page *page, int ret)
 127 {
 128         if (ret == 0) {
 129                 /* Everything is OK */
 130                 SetPageUptodate(page);
 131                 if (PageError(page))
 132                         ClearPageError(page);
 133         } else if (ret == -EFAULT) {
 134                 /* In this case we were trying to read something that wasn't on
 135                  * disk yet - return a page full of zeroes.  This should be OK,
 136                  * because the object should be empty (if there was a write
 137                  * before this read, the read would be waiting with the page
 138                  * locked */
 139                 clear_highpage(page);
 140
 141                 SetPageUptodate(page);
 142                 if (PageError(page))
 143                         ClearPageError(page);
 144                 ret = 0; /* recovered error */
 145                 EXOFS_DBGMSG("recovered read error\n");
 146         } else /* Error */
 147                 SetPageError(page);
 148
 149         return ret;
 150 }
 151
 152 static void update_write_page(struct page *page, int ret)
 153 {
 154         if (ret) {
 155                 mapping_set_error(page->mapping, ret);
 156                 SetPageError(page);
 157         }
 158         end_page_writeback(page);
 159 }
 160
 161 /* Called at the end of reads, to optionally unlock pages and update their
 162  * status.
 163  */
 164 static int __readpages_done(struct osd_request *or, struct page_collect *pcol,
 165                             bool do_unlock)
 166 {
 167         struct bio_vec *bvec;
 168         int i;
 169         u64 resid;
 170         u64 good_bytes;
 171         u64 length = 0;
 172         int ret = exofs_check_ok_resid(or, &resid, NULL);
 173
 174         osd_end_request(or);
 175
 176         if (likely(!ret))
 177                 good_bytes = pcol->length;
 178         else if (!resid)
 179                 good_bytes = 0;
 180         else
 181                 good_bytes = pcol->length - resid;
 182
 183         EXOFS_DBGMSG("readpages_done(0x%lx) good_bytes=0x%llx"
 184                      " length=0x%lx nr_pages=%u\n",
 185                      pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 186                      pcol->nr_pages);
 187
 188         __bio_for_each_segment(bvec, pcol->bio, i, 0) {
 189                 struct page *page = bvec->bv_page;
 190                 struct inode *inode = page->mapping->host;
 191                 int page_stat;
 192
 193                 if (inode != pcol->inode)
 194                         continue; /* osd might add more pages at end */
 195
 196                 if (likely(length < good_bytes))
 197                         page_stat = 0;
 198                 else
 199                         page_stat = ret;
 200
 201                 EXOFS_DBGMSG("    readpages_done(0x%lx, 0x%lx) %s\n",
 202                           inode->i_ino, page->index,
 203                           page_stat ? "bad_bytes" : "good_bytes");
 204
 205                 ret = update_read_page(page, page_stat);
 206                 if (do_unlock)
 207                         unlock_page(page);
 208                 length += bvec->bv_len;
 209         }
 210
 211         pcol_free(pcol);
 212         EXOFS_DBGMSG("readpages_done END\n");
 213         return ret;
 214 }
 215
 216 /* callback of async reads */
 217 static void readpages_done(struct osd_request *or, void *p)
 218 {
 219         struct page_collect *pcol = p;
 220
 221         __readpages_done(or, pcol, true);
 222         atomic_dec(&pcol->sbi->s_curr_pending);
 223         kfree(p);
 224 }
 225
 226 static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
 227 {
 228         struct bio_vec *bvec;
 229         int i;
 230
 231         __bio_for_each_segment(bvec, pcol->bio, i, 0) {
 232                 struct page *page = bvec->bv_page;
 233
 234                 if (rw == READ)
 235                         update_read_page(page, ret);
 236                 else
 237                         update_write_page(page, ret);
 238
 239                 unlock_page(page);
 240         }
 241         pcol_free(pcol);
 242 }
 243
 244 static int read_exec(struct page_collect *pcol, bool is_sync)
 245 {
 246         struct exofs_i_info *oi = exofs_i(pcol->inode);
 247         struct osd_obj_id obj = {pcol->sbi->s_pid,
 248                                         pcol->inode->i_ino + EXOFS_OBJ_OFF};
 249         struct osd_request *or = NULL;
 250         struct page_collect *pcol_copy = NULL;
 251         loff_t i_start = pcol->pg_first << PAGE_CACHE_SHIFT;
 252         int ret;
 253
 254         if (!pcol->bio)
 255                 return 0;
 256
 257         /* see comment in _readpage() about sync reads */
 258         WARN_ON(is_sync && (pcol->nr_pages != 1));
 259
 260         or = osd_start_request(pcol->sbi->s_dev, GFP_KERNEL);
 261         if (unlikely(!or)) {
 262                 ret = -ENOMEM;
 263                 goto err;
 264         }
 265
 266         osd_req_read(or, &obj, i_start, pcol->bio, pcol->length);
 267
 268         if (is_sync) {
 269                 exofs_sync_op(or, pcol->sbi->s_timeout, oi->i_cred);
 270                 return __readpages_done(or, pcol, false);
 271         }
 272
 273         pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 274         if (!pcol_copy) {
 275                 ret = -ENOMEM;
 276                 goto err;
 277         }
 278
 279         *pcol_copy = *pcol;
 280         ret = exofs_async_op(or, readpages_done, pcol_copy, oi->i_cred);
 281         if (unlikely(ret))
 282                 goto err;
 283
 284         atomic_inc(&pcol->sbi->s_curr_pending);
 285
 286         EXOFS_DBGMSG("read_exec obj=0x%llx start=0x%llx length=0x%lx\n",
 287                   obj.id, _LLU(i_start), pcol->length);
 288
 289         /* pages ownership was passed to pcol_copy */
 290         _pcol_reset(pcol);
 291         return 0;
 292
 293 err:
 294         if (!is_sync)
 295                 _unlock_pcol_pages(pcol, ret, READ);
 296         else /* Pages unlocked by caller in sync mode only free bio */
 297                 pcol_free(pcol);
 298
 299         kfree(pcol_copy);
 300         if (or)
 301                 osd_end_request(or);
 302         return ret;
 303 }
 304
 305 /* readpage_strip is called either directly from readpage() or by the VFS from
 306  * within read_cache_pages(), to add one more page to be read. It will try to
 307  * collect as many contiguous pages as posible. If a discontinuity is
 308  * encountered, or it runs out of resources, it will submit the previous segment
 309  * and will start a new collection. Eventually caller must submit the last
 310  * segment if present.
 311  */
 312 static int readpage_strip(void *data, struct page *page)
 313 {
 314         struct page_collect *pcol = data;
 315         struct inode *inode = pcol->inode;
 316         struct exofs_i_info *oi = exofs_i(inode);
 317         loff_t i_size = i_size_read(inode);
 318         pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 319         size_t len;
 320         int ret;
 321
 322         /* FIXME: Just for debugging, will be removed */
 323         if (PageUptodate(page))
 324                 EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino,
 325                           page->index);
 326
 327         if (page->index < end_index)
 328                 len = PAGE_CACHE_SIZE;
 329         else if (page->index == end_index)
 330                 len = i_size & ~PAGE_CACHE_MASK;
 331         else
 332                 len = 0;
 333
 334         if (!len || !obj_created(oi)) {
 335                 /* this will be out of bounds, or doesn't exist yet.
 336                  * Current page is cleared and the request is split
 337                  */
 338                 clear_highpage(page);
 339
 340                 SetPageUptodate(page);
 341                 if (PageError(page))
 342                         ClearPageError(page);
 343
 344                 unlock_page(page);
 345                 EXOFS_DBGMSG("readpage_strip(0x%lx, 0x%lx) empty page,"
 346                              " splitting\n", inode->i_ino, page->index);
 347
 348                 return read_exec(pcol, false);
 349         }
 350
 351 try_again:
 352
 353         if (unlikely(pcol->pg_first == -1)) {
 354                 pcol->pg_first = page->index;
 355         } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
 356                    page->index)) {
 357                 /* Discontinuity detected, split the request */
 358                 ret = read_exec(pcol, false);
 359                 if (unlikely(ret))
 360                         goto fail;
 361                 goto try_again;
 362         }
 363
 364         if (!pcol->bio) {
 365                 ret = pcol_try_alloc(pcol);
 366                 if (unlikely(ret))
 367                         goto fail;
 368         }
 369
 370         if (len != PAGE_CACHE_SIZE)
 371                 zero_user(page, len, PAGE_CACHE_SIZE - len);
 372
 373         EXOFS_DBGMSG("    readpage_strip(0x%lx, 0x%lx) len=0x%zx\n",
 374                      inode->i_ino, page->index, len);
 375
 376         ret = pcol_add_page(pcol, page, len);
 377         if (ret) {
 378                 EXOFS_DBGMSG("Failed pcol_add_page pages[i]=%p "
 379                           "this_len=0x%zx nr_pages=%u length=0x%lx\n",
 380                           page, len, pcol->nr_pages, pcol->length);
 381
 382                 /* split the request, and start again with current page */
 383                 ret = read_exec(pcol, false);
 384                 if (unlikely(ret))
 385                         goto fail;
 386
 387                 goto try_again;
 388         }
 389
 390         return 0;
 391
 392 fail:
 393         /* SetPageError(page); ??? */
 394         unlock_page(page);
 395         return ret;
 396 }
 397
 398 static int exofs_readpages(struct file *file, struct address_space *mapping,
 399                            struct list_head *pages, unsigned nr_pages)
 400 {
 401         struct page_collect pcol;
 402         int ret;
 403
 404         _pcol_init(&pcol, nr_pages, mapping->host);
 405
 406         ret = read_cache_pages(mapping, pages, readpage_strip, &pcol);
 407         if (ret) {
 408                 EXOFS_ERR("read_cache_pages => %d\n", ret);
 409                 return ret;
 410         }
 411
 412         return read_exec(&pcol, false);
 413 }
 414
 415 static int _readpage(struct page *page, bool is_sync)
 416 {
 417         struct page_collect pcol;
 418         int ret;
 419
 420         _pcol_init(&pcol, 1, page->mapping->host);
 421
 422         /* readpage_strip might call read_exec(,async) inside at several places
 423          * but this is safe for is_async=0 since read_exec will not do anything
 424          * when we have a single page.
 425          */
 426         ret = readpage_strip(&pcol, page);
 427         if (ret) {
 428                 EXOFS_ERR("_readpage => %d\n", ret);
 429                 return ret;
 430         }
 431
 432         return read_exec(&pcol, is_sync);
 433 }
 434
 435 /*
 436  * We don't need the file
 437  */
 438 static int exofs_readpage(struct file *file, struct page *page)
 439 {
 440         return _readpage(page, false);
 441 }
 442
 443 /* Callback for osd_write. All writes are asynchronouse */
 444 static void writepages_done(struct osd_request *or, void *p)
 445 {
 446         struct page_collect *pcol = p;
 447         struct bio_vec *bvec;
 448         int i;
 449         u64 resid;
 450         u64  good_bytes;
 451         u64  length = 0;
 452
 453         int ret = exofs_check_ok_resid(or, NULL, &resid);
 454
 455         osd_end_request(or);
 456         atomic_dec(&pcol->sbi->s_curr_pending);
 457
 458         if (likely(!ret))
 459                 good_bytes = pcol->length;
 460         else if (!resid)
 461                 good_bytes = 0;
 462         else
 463                 good_bytes = pcol->length - resid;
 464
 465         EXOFS_DBGMSG("writepages_done(0x%lx) good_bytes=0x%llx"
 466                      " length=0x%lx nr_pages=%u\n",
 467                      pcol->inode->i_ino, _LLU(good_bytes), pcol->length,
 468                      pcol->nr_pages);
 469
 470         __bio_for_each_segment(bvec, pcol->bio, i, 0) {
 471                 struct page *page = bvec->bv_page;
 472                 struct inode *inode = page->mapping->host;
 473                 int page_stat;
 474
 475                 if (inode != pcol->inode)
 476                         continue; /* osd might add more pages to a bio */
 477
 478                 if (likely(length < good_bytes))
 479                         page_stat = 0;
 480                 else
 481                         page_stat = ret;
 482
 483                 update_write_page(page, page_stat);
 484                 unlock_page(page);
 485                 EXOFS_DBGMSG("    writepages_done(0x%lx, 0x%lx) status=%d\n",
 486                              inode->i_ino, page->index, page_stat);
 487
 488                 length += bvec->bv_len;
 489         }
 490
 491         pcol_free(pcol);
 492         kfree(pcol);
 493         EXOFS_DBGMSG("writepages_done END\n");
 494 }
 495
 496 static int write_exec(struct page_collect *pcol)
 497 {
 498         struct exofs_i_info *oi = exofs_i(pcol->inode);
 499         struct osd_obj_id obj = {pcol->sbi->s_pid,
 500                                         pcol->inode->i_ino + EXOFS_OBJ_OFF};
 501         struct osd_request *or = NULL;
 502         struct page_collect *pcol_copy = NULL;
 503         loff_t i_start = pcol->pg_first << PAGE_CACHE_SHIFT;
 504         int ret;
 505
 506         if (!pcol->bio)
 507                 return 0;
 508
 509         or = osd_start_request(pcol->sbi->s_dev, GFP_KERNEL);
 510         if (unlikely(!or)) {
 511                 EXOFS_ERR("write_exec: Faild to osd_start_request()\n");
 512                 ret = -ENOMEM;
 513                 goto err;
 514         }
 515
 516         pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
 517         if (!pcol_copy) {
 518                 EXOFS_ERR("write_exec: Faild to kmalloc(pcol)\n");
 519                 ret = -ENOMEM;
 520                 goto err;
 521         }
 522
 523         *pcol_copy = *pcol;
 524
 525         pcol_copy->bio->bi_rw |= (1 << BIO_RW); /* FIXME: bio_set_dir() */
 526         osd_req_write(or, &obj, i_start, pcol_copy->bio, pcol_copy->length);
 527         ret = exofs_async_op(or, writepages_done, pcol_copy, oi->i_cred);
 528         if (unlikely(ret)) {
 529                 EXOFS_ERR("write_exec: exofs_async_op() Faild\n");
 530                 goto err;
 531         }
 532
 533         atomic_inc(&pcol->sbi->s_curr_pending);
 534         EXOFS_DBGMSG("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n",
 535                   pcol->inode->i_ino, pcol->pg_first, _LLU(i_start),
 536                   pcol->length);
 537         /* pages ownership was passed to pcol_copy */
 538         _pcol_reset(pcol);
 539         return 0;
 540
 541 err:
 542         _unlock_pcol_pages(pcol, ret, WRITE);
 543         kfree(pcol_copy);
 544         if (or)
 545                 osd_end_request(or);
 546         return ret;
 547 }
 548
 549 /* writepage_strip is called either directly from writepage() or by the VFS from
 550  * within write_cache_pages(), to add one more page to be written to storage.
 551  * It will try to collect as many contiguous pages as possible. If a
 552  * discontinuity is encountered or it runs out of resources it will submit the
 553  * previous segment and will start a new collection.
 554  * Eventually caller must submit the last segment if present.
 555  */
 556 static int writepage_strip(struct page *page,
 557                            struct writeback_control *wbc_unused, void *data)
 558 {
 559         struct page_collect *pcol = data;
 560         struct inode *inode = pcol->inode;
 561         struct exofs_i_info *oi = exofs_i(inode);
 562         loff_t i_size = i_size_read(inode);
 563         pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
 564         size_t len;
 565         int ret;
 566
 567         BUG_ON(!PageLocked(page));
 568
 569         ret = wait_obj_created(oi);
 570         if (unlikely(ret))
 571                 goto fail;
 572
 573         if (page->index < end_index)
 574                 /* in this case, the page is within the limits of the file */
 575                 len = PAGE_CACHE_SIZE;
 576         else {
 577                 len = i_size & ~PAGE_CACHE_MASK;
 578
 579                 if (page->index > end_index || !len) {
 580                         /* in this case, the page is outside the limits
 581                          * (truncate in progress)
 582                          */
 583                         ret = write_exec(pcol);
 584                         if (unlikely(ret))
 585                                 goto fail;
 586                         if (PageError(page))
 587                                 ClearPageError(page);
 588                         unlock_page(page);
 589                         return 0;
 590                 }
 591         }
 592
 593 try_again:
 594
 595         if (unlikely(pcol->pg_first == -1)) {
 596                 pcol->pg_first = page->index;
 597         } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
 598                    page->index)) {
 599                 /* Discontinuity detected, split the request */
 600                 ret = write_exec(pcol);
 601                 if (unlikely(ret))
 602                         goto fail;
 603                 goto try_again;
 604         }
 605
 606         if (!pcol->bio) {
 607                 ret = pcol_try_alloc(pcol);
 608                 if (unlikely(ret))
 609                         goto fail;
 610         }
 611
 612         EXOFS_DBGMSG("    writepage_strip(0x%lx, 0x%lx) len=0x%zx\n",
 613                      inode->i_ino, page->index, len);
 614
 615         ret = pcol_add_page(pcol, page, len);
 616         if (unlikely(ret)) {
 617                 EXOFS_DBGMSG("Failed pcol_add_page "
 618                              "nr_pages=%u total_length=0x%lx\n",
 619                              pcol->nr_pages, pcol->length);
 620
 621                 /* split the request, next loop will start again */
 622                 ret = write_exec(pcol);
 623                 if (unlikely(ret)) {
 624                         EXOFS_DBGMSG("write_exec faild => %d", ret);
 625                         goto fail;
 626                 }
 627
 628                 goto try_again;
 629         }
 630
 631         BUG_ON(PageWriteback(page));
 632         set_page_writeback(page);
 633
 634         return 0;
 635
 636 fail:
 637         set_bit(AS_EIO, &page->mapping->flags);
 638         unlock_page(page);
 639         return ret;
 640 }
 641
 642 static int exofs_writepages(struct address_space *mapping,
 643                        struct writeback_control *wbc)
 644 {
 645         struct page_collect pcol;
 646         long start, end, expected_pages;
 647         int ret;
 648
 649         start = wbc->range_start >> PAGE_CACHE_SHIFT;
 650         end = (wbc->range_end == LLONG_MAX) ?
 651                         start + mapping->nrpages :
 652                         wbc->range_end >> PAGE_CACHE_SHIFT;
 653
 654         if (start || end)
 655                 expected_pages = min(end - start + 1, 32L);
 656         else
 657                 expected_pages = mapping->nrpages;
 658
 659         EXOFS_DBGMSG("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx"
 660                      " m->nrpages=%lu start=0x%lx end=0x%lx\n",
 661                      mapping->host->i_ino, wbc->range_start, wbc->range_end,
 662                      mapping->nrpages, start, end);
 663
 664         _pcol_init(&pcol, expected_pages, mapping->host);
 665
 666         ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol);
 667         if (ret) {
 668                 EXOFS_ERR("write_cache_pages => %d\n", ret);
 669                 return ret;
 670         }
 671
 672         return write_exec(&pcol);
 673 }
 674
 675 static int exofs_writepage(struct page *page, struct writeback_control *wbc)
 676 {
 677         struct page_collect pcol;
 678         int ret;
 679
 680         _pcol_init(&pcol, 1, page->mapping->host);
 681
 682         ret = writepage_strip(page, NULL, &pcol);
 683         if (ret) {
 684                 EXOFS_ERR("exofs_writepage => %d\n", ret);
 685                 return ret;
 686         }
 687
 688         return write_exec(&pcol);
 689 }
 690
 691 int exofs_write_begin(struct file *file, struct address_space *mapping,
 692                 loff_t pos, unsigned len, unsigned flags,
 693                 struct page **pagep, void **fsdata)
 694 {
 695         int ret = 0;
 696         struct page *page;
 697
 698         page = *pagep;
 699         if (page == NULL) {
 700                 ret = simple_write_begin(file, mapping, pos, len, flags, pagep,
 701                                          fsdata);
 702                 if (ret) {
 703                         EXOFS_DBGMSG("simple_write_begin faild\n");
 704                         return ret;
 705                 }
 706
 707                 page = *pagep;
 708         }
 709
 710          /* read modify write */
 711         if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
 712                 ret = _readpage(page, true);
 713                 if (ret) {
 714                         /*SetPageError was done by _readpage. Is it ok?*/
 715                         unlock_page(page);
 716                         EXOFS_DBGMSG("__readpage_filler faild\n");
 717                 }
 718         }
 719
 720         return ret;
 721 }
 722
 723 static int exofs_write_begin_export(struct file *file,
 724                 struct address_space *mapping,
 725                 loff_t pos, unsigned len, unsigned flags,
 726                 struct page **pagep, void **fsdata)
 727 {
 728         *pagep = NULL;
 729
 730         return exofs_write_begin(file, mapping, pos, len, flags, pagep,
 731                                         fsdata);
 732 }
 733
 734 const struct address_space_operations exofs_aops = {
 735         .readpage       = exofs_readpage,
 736         .readpages      = exofs_readpages,
 737         .writepage      = exofs_writepage,
 738         .writepages     = exofs_writepages,
 739         .write_begin    = exofs_write_begin_export,
 740         .write_end      = simple_write_end,
 741 };
 742
 743 /******************************************************************************
 744  * INODE OPERATIONS
 745  *****************************************************************************/
 746
 747 /*
 748  * Test whether an inode is a fast symlink.
 749  */
 750 static inline int exofs_inode_is_fast_symlink(struct inode *inode)
 751 {
 752         struct exofs_i_info *oi = exofs_i(inode);
 753
 754         return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0);
 755 }
 756
 757 /*
 758  * get_block_t - Fill in a buffer_head
 759  * An OSD takes care of block allocation so we just fake an allocation by
 760  * putting in the inode's sector_t in the buffer_head.
 761  * TODO: What about the case of create==0 and @iblock does not exist in the
 762  * object?
 763  */
 764 static int exofs_get_block(struct inode *inode, sector_t iblock,
 765                     struct buffer_head *bh_result, int create)
 766 {
 767         map_bh(bh_result, inode->i_sb, iblock);
 768         return 0;
 769 }
 770
 771 const struct osd_attr g_attr_logical_length = ATTR_DEF(
 772         OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8);
 773
 774 /*
 775  * Truncate a file to the specified size - all we have to do is set the size
 776  * attribute.  We make sure the object exists first.
 777  */
 778 void exofs_truncate(struct inode *inode)
 779 {
 780         struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
 781         struct exofs_i_info *oi = exofs_i(inode);
 782         struct osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF};
 783         struct osd_request *or;
 784         struct osd_attr attr;
 785         loff_t isize = i_size_read(inode);
 786         __be64 newsize;
 787         int ret;
 788
 789         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
 790              || S_ISLNK(inode->i_mode)))
 791                 return;
 792         if (exofs_inode_is_fast_symlink(inode))
 793                 return;
 794         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 795                 return;
 796         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 797
 798         nobh_truncate_page(inode->i_mapping, isize, exofs_get_block);
 799
 800         or = osd_start_request(sbi->s_dev, GFP_KERNEL);
 801         if (unlikely(!or)) {
 802                 EXOFS_ERR("ERROR: exofs_truncate: osd_start_request failed\n");
 803                 goto fail;
 804         }
 805
 806         osd_req_set_attributes(or, &obj);
 807
 808         newsize = cpu_to_be64((u64)isize);
 809         attr = g_attr_logical_length;
 810         attr.val_ptr = &newsize;
 811         osd_req_add_set_attr_list(or, &attr, 1);
 812
 813         /* if we are about to truncate an object, and it hasn't been
 814          * created yet, wait
 815          */
 816         if (unlikely(wait_obj_created(oi)))
 817                 goto fail;
 818
 819         ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
 820         osd_end_request(or);
 821         if (ret)
 822                 goto fail;
 823
 824 out:
 825         mark_inode_dirty(inode);
 826         return;
 827 fail:
 828         make_bad_inode(inode);
 829         goto out;
 830 }
 831
 832 /*
 833  * Set inode attributes - just call generic functions.
 834  */
 835 int exofs_setattr(struct dentry *dentry, struct iattr *iattr)
 836 {
 837         struct inode *inode = dentry->d_inode;
 838         int error;
 839
 840         error = inode_change_ok(inode, iattr);
 841         if (error)
 842                 return error;
 843
 844         error = inode_setattr(inode, iattr);
 845         return error;
 846 }
 847
 848 /*
 849  * Read an inode from the OSD, and return it as is.  We also return the size
 850  * attribute in the 'sanity' argument if we got compiled with debugging turned
 851  * on.
 852  */
 853 static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
 854                     struct exofs_fcb *inode, uint64_t *sanity)
 855 {
 856         struct exofs_sb_info *sbi = sb->s_fs_info;
 857         struct osd_request *or;
 858         struct osd_attr attr;
 859         struct osd_obj_id obj = {sbi->s_pid,
 860                                  oi->vfs_inode.i_ino + EXOFS_OBJ_OFF};
 861         int ret;
 862
 863         exofs_make_credential(oi->i_cred, &obj);
 864
 865         or = osd_start_request(sbi->s_dev, GFP_KERNEL);
 866         if (unlikely(!or)) {
 867                 EXOFS_ERR("exofs_get_inode: osd_start_request failed.\n");
 868                 return -ENOMEM;
 869         }
 870         osd_req_get_attributes(or, &obj);
 871
 872         /* we need the inode attribute */
 873         osd_req_add_get_attr_list(or, &g_attr_inode_data, 1);
 874
 875 #ifdef EXOFS_DEBUG_OBJ_ISIZE
 876         /* we get the size attributes to do a sanity check */
 877         osd_req_add_get_attr_list(or, &g_attr_logical_length, 1);
 878 #endif
 879
 880         ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
 881         if (ret)
 882                 goto out;
 883
 884         attr = g_attr_inode_data;
 885         ret = extract_attr_from_req(or, &attr);
 886         if (ret) {
 887                 EXOFS_ERR("exofs_get_inode: extract_attr_from_req failed\n");
 888                 goto out;
 889         }
 890
 891         WARN_ON(attr.len != EXOFS_INO_ATTR_SIZE);
 892         memcpy(inode, attr.val_ptr, EXOFS_INO_ATTR_SIZE);
 893
 894 #ifdef EXOFS_DEBUG_OBJ_ISIZE
 895         attr = g_attr_logical_length;
 896         ret = extract_attr_from_req(or, &attr);
 897         if (ret) {
 898                 EXOFS_ERR("ERROR: extract attr from or failed\n");
 899                 goto out;
 900         }
 901         *sanity = get_unaligned_be64(attr.val_ptr);
 902 #endif
 903
 904 out:
 905         osd_end_request(or);
 906         return ret;
 907 }
 908
 909 /*
 910  * Fill in an inode read from the OSD and set it up for use
 911  */
 912 struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
 913 {
 914         struct exofs_i_info *oi;
 915         struct exofs_fcb fcb;
 916         struct inode *inode;
 917         uint64_t uninitialized_var(sanity);
 918         int ret;
 919
 920         inode = iget_locked(sb, ino);
 921         if (!inode)
 922                 return ERR_PTR(-ENOMEM);
 923         if (!(inode->i_state & I_NEW))
 924                 return inode;
 925         oi = exofs_i(inode);
 926
 927         /* read the inode from the osd */
 928         ret = exofs_get_inode(sb, oi, &fcb, &sanity);
 929         if (ret)
 930                 goto bad_inode;
 931
 932         init_waitqueue_head(&oi->i_wq);
 933         set_obj_created(oi);
 934
 935         /* copy stuff from on-disk struct to in-memory struct */
 936         inode->i_mode = le16_to_cpu(fcb.i_mode);
 937         inode->i_uid = le32_to_cpu(fcb.i_uid);
 938         inode->i_gid = le32_to_cpu(fcb.i_gid);
 939         inode->i_nlink = le16_to_cpu(fcb.i_links_count);
 940         inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime);
 941         inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime);
 942         inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime);
 943         inode->i_ctime.tv_nsec =
 944                 inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0;
 945         oi->i_commit_size = le64_to_cpu(fcb.i_size);
 946         i_size_write(inode, oi->i_commit_size);
 947         inode->i_blkbits = EXOFS_BLKSHIFT;
 948         inode->i_generation = le32_to_cpu(fcb.i_generation);
 949
 950 #ifdef EXOFS_DEBUG_OBJ_ISIZE
 951         if ((inode->i_size != sanity) &&
 952                 (!exofs_inode_is_fast_symlink(inode))) {
 953                 EXOFS_ERR("WARNING: Size of object from inode and "
 954                           "attributes differ (%lld != %llu)\n",
 955                           inode->i_size, _LLU(sanity));
 956         }
 957 #endif
 958
 959         oi->i_dir_start_lookup = 0;
 960
 961         if ((inode->i_nlink == 0) && (inode->i_mode == 0)) {
 962                 ret = -ESTALE;
 963                 goto bad_inode;
 964         }
 965
 966         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
 967                 if (fcb.i_data[0])
 968                         inode->i_rdev =
 969                                 old_decode_dev(le32_to_cpu(fcb.i_data[0]));
 970                 else
 971                         inode->i_rdev =
 972                                 new_decode_dev(le32_to_cpu(fcb.i_data[1]));
 973         } else {
 974                 memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
 975         }
 976
 977         if (S_ISREG(inode->i_mode)) {
 978                 inode->i_op = &exofs_file_inode_operations;
 979                 inode->i_fop = &exofs_file_operations;
 980                 inode->i_mapping->a_ops = &exofs_aops;
 981         } else if (S_ISDIR(inode->i_mode)) {
 982                 inode->i_op = &exofs_dir_inode_operations;
 983                 inode->i_fop = &exofs_dir_operations;
 984                 inode->i_mapping->a_ops = &exofs_aops;
 985         } else if (S_ISLNK(inode->i_mode)) {
 986                 if (exofs_inode_is_fast_symlink(inode))
 987                         inode->i_op = &exofs_fast_symlink_inode_operations;
 988                 else {
 989                         inode->i_op = &exofs_symlink_inode_operations;
 990                         inode->i_mapping->a_ops = &exofs_aops;
 991                 }
 992         } else {
 993                 inode->i_op = &exofs_special_inode_operations;
 994                 if (fcb.i_data[0])
 995                         init_special_inode(inode, inode->i_mode,
 996                            old_decode_dev(le32_to_cpu(fcb.i_data[0])));
 997                 else
 998                         init_special_inode(inode, inode->i_mode,
 999                            new_decode_dev(le32_to_cpu(fcb.i_data[1])));
1000         }
1001
1002         unlock_new_inode(inode);
1003         return inode;
1004
1005 bad_inode:
1006         iget_failed(inode);
1007         return ERR_PTR(ret);
1008 }
1009
1010 int __exofs_wait_obj_created(struct exofs_i_info *oi)
1011 {
1012         if (!obj_created(oi)) {
1013                 BUG_ON(!obj_2bcreated(oi));
1014                 wait_event(oi->i_wq, obj_created(oi));
1015         }
1016         return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0;
1017 }
1018 /*
1019  * Callback function from exofs_new_inode().  The important thing is that we
1020  * set the obj_created flag so that other methods know that the object exists on
1021  * the OSD.
1022  */
1023 static void create_done(struct osd_request *or, void *p)
1024 {
1025         struct inode *inode = p;
1026         struct exofs_i_info *oi = exofs_i(inode);
1027         struct exofs_sb_info *sbi = inode->i_sb->s_fs_info;
1028         int ret;
1029
1030         ret = exofs_check_ok(or);
1031         osd_end_request(or);
1032         atomic_dec(&sbi->s_curr_pending);
1033
1034         if (unlikely(ret)) {
1035                 EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx",
1036                           _LLU(sbi->s_pid), _LLU(inode->i_ino + EXOFS_OBJ_OFF));
1037                 make_bad_inode(inode);
1038         } else
1039                 set_obj_created(oi);
1040
1041         atomic_dec(&inode->i_count);
1042         wake_up(&oi->i_wq);
1043 }
1044
1045 /*
1046  * Set up a new inode and create an object for it on the OSD
1047  */
1048 struct inode *exofs_new_inode(struct inode *dir, int mode)
1049 {
1050         struct super_block *sb;
1051         struct inode *inode;
1052         struct exofs_i_info *oi;
1053         struct exofs_sb_info *sbi;
1054         struct osd_request *or;
1055         struct osd_obj_id obj;
1056         int ret;
1057
1058         sb = dir->i_sb;
1059         inode = new_inode(sb);
1060         if (!inode)
1061                 return ERR_PTR(-ENOMEM);
1062
1063         oi = exofs_i(inode);
1064
1065         init_waitqueue_head(&oi->i_wq);
1066         set_obj_2bcreated(oi);
1067
1068         sbi = sb->s_fs_info;
1069
1070         sb->s_dirt = 1;
1071         inode->i_uid = current->cred->fsuid;
1072         if (dir->i_mode & S_ISGID) {
1073                 inode->i_gid = dir->i_gid;
1074                 if (S_ISDIR(mode))
1075                         mode |= S_ISGID;
1076         } else {
1077                 inode->i_gid = current->cred->fsgid;
1078         }
1079         inode->i_mode = mode;
1080
1081         inode->i_ino = sbi->s_nextid++;
1082         inode->i_blkbits = EXOFS_BLKSHIFT;
1083         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1084         oi->i_commit_size = inode->i_size = 0;
1085         spin_lock(&sbi->s_next_gen_lock);
1086         inode->i_generation = sbi->s_next_generation++;
1087         spin_unlock(&sbi->s_next_gen_lock);
1088         insert_inode_hash(inode);
1089
1090         mark_inode_dirty(inode);
1091
1092         obj.partition = sbi->s_pid;
1093         obj.id = inode->i_ino + EXOFS_OBJ_OFF;
1094         exofs_make_credential(oi->i_cred, &obj);
1095
1096         or = osd_start_request(sbi->s_dev, GFP_KERNEL);
1097         if (unlikely(!or)) {
1098                 EXOFS_ERR("exofs_new_inode: osd_start_request failed\n");
1099                 return ERR_PTR(-ENOMEM);
1100         }
1101
1102         osd_req_create_object(or, &obj);
1103
1104         /* increment the refcount so that the inode will still be around when we
1105          * reach the callback
1106          */
1107         atomic_inc(&inode->i_count);
1108
1109         ret = exofs_async_op(or, create_done, inode, oi->i_cred);
1110         if (ret) {
1111                 atomic_dec(&inode->i_count);
1112                 osd_end_request(or);
1113                 return ERR_PTR(-EIO);
1114         }
1115         atomic_inc(&sbi->s_curr_pending);
1116
1117         return inode;
1118 }
1119
1120 /*
1121  * struct to pass two arguments to update_inode's callback
1122  */
1123 struct updatei_args {
1124         struct exofs_sb_info    *sbi;
1125         struct exofs_fcb        fcb;
1126 };
1127
1128 /*
1129  * Callback function from exofs_update_inode().
1130  */
1131 static void updatei_done(struct osd_request *or, void *p)
1132 {
1133         struct updatei_args *args = p;
1134
1135         osd_end_request(or);
1136
1137         atomic_dec(&args->sbi->s_curr_pending);
1138
1139         kfree(args);
1140 }
1141
1142 /*
1143  * Write the inode to the OSD.  Just fill up the struct, and set the attribute
1144  * synchronously or asynchronously depending on the do_sync flag.
1145  */
1146 static int exofs_update_inode(struct inode *inode, int do_sync)
1147 {
1148         struct exofs_i_info *oi = exofs_i(inode);
1149         struct super_block *sb = inode->i_sb;
1150         struct exofs_sb_info *sbi = sb->s_fs_info;
1151         struct osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF};
1152         struct osd_request *or;
1153         struct osd_attr attr;
1154         struct exofs_fcb *fcb;
1155         struct updatei_args *args;
1156         int ret;
1157
1158         args = kzalloc(sizeof(*args), GFP_KERNEL);
1159         if (!args)
1160                 return -ENOMEM;
1161
1162         fcb = &args->fcb;
1163
1164         fcb->i_mode = cpu_to_le16(inode->i_mode);
1165         fcb->i_uid = cpu_to_le32(inode->i_uid);
1166         fcb->i_gid = cpu_to_le32(inode->i_gid);
1167         fcb->i_links_count = cpu_to_le16(inode->i_nlink);
1168         fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
1169         fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
1170         fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
1171         oi->i_commit_size = i_size_read(inode);
1172         fcb->i_size = cpu_to_le64(oi->i_commit_size);
1173         fcb->i_generation = cpu_to_le32(inode->i_generation);
1174
1175         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
1176                 if (old_valid_dev(inode->i_rdev)) {
1177                         fcb->i_data[0] =
1178                                 cpu_to_le32(old_encode_dev(inode->i_rdev));
1179                         fcb->i_data[1] = 0;
1180                 } else {
1181                         fcb->i_data[0] = 0;
1182                         fcb->i_data[1] =
1183                                 cpu_to_le32(new_encode_dev(inode->i_rdev));
1184                         fcb->i_data[2] = 0;
1185                 }
1186         } else
1187                 memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data));
1188
1189         or = osd_start_request(sbi->s_dev, GFP_KERNEL);
1190         if (unlikely(!or)) {
1191                 EXOFS_ERR("exofs_update_inode: osd_start_request failed.\n");
1192                 ret = -ENOMEM;
1193                 goto free_args;
1194         }
1195
1196         osd_req_set_attributes(or, &obj);
1197
1198         attr = g_attr_inode_data;
1199         attr.val_ptr = fcb;
1200         osd_req_add_set_attr_list(or, &attr, 1);
1201
1202         if (!obj_created(oi)) {
1203                 EXOFS_DBGMSG("!obj_created\n");
1204                 BUG_ON(!obj_2bcreated(oi));
1205                 wait_event(oi->i_wq, obj_created(oi));
1206                 EXOFS_DBGMSG("wait_event done\n");
1207         }
1208
1209         if (do_sync) {
1210                 ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
1211                 osd_end_request(or);
1212                 goto free_args;
1213         } else {
1214                 args->sbi = sbi;
1215
1216                 ret = exofs_async_op(or, updatei_done, args, oi->i_cred);
1217                 if (ret) {
1218                         osd_end_request(or);
1219                         goto free_args;
1220                 }
1221                 atomic_inc(&sbi->s_curr_pending);
1222                 goto out; /* deallocation in updatei_done */
1223         }
1224
1225 free_args:
1226         kfree(args);
1227 out:
1228         EXOFS_DBGMSG("ret=>%d\n", ret);
1229         return ret;
1230 }
1231
1232 int exofs_write_inode(struct inode *inode, int wait)
1233 {
1234         return exofs_update_inode(inode, wait);
1235 }
1236
1237 /*
1238  * Callback function from exofs_delete_inode() - don't have much cleaning up to
1239  * do.
1240  */
1241 static void delete_done(struct osd_request *or, void *p)
1242 {
1243         struct exofs_sb_info *sbi;
1244         osd_end_request(or);
1245         sbi = p;
1246         atomic_dec(&sbi->s_curr_pending);
1247 }
1248
1249 /*
1250  * Called when the refcount of an inode reaches zero.  We remove the object
1251  * from the OSD here.  We make sure the object was created before we try and
1252  * delete it.
1253  */
1254 void exofs_delete_inode(struct inode *inode)
1255 {
1256         struct exofs_i_info *oi = exofs_i(inode);
1257         struct super_block *sb = inode->i_sb;
1258         struct exofs_sb_info *sbi = sb->s_fs_info;
1259         struct osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF};
1260         struct osd_request *or;
1261         int ret;
1262
1263         truncate_inode_pages(&inode->i_data, 0);
1264
1265         if (is_bad_inode(inode))
1266                 goto no_delete;
1267
1268         mark_inode_dirty(inode);
1269         exofs_update_inode(inode, inode_needs_sync(inode));
1270
1271         inode->i_size = 0;
1272         if (inode->i_blocks)
1273                 exofs_truncate(inode);
1274
1275         clear_inode(inode);
1276
1277         or = osd_start_request(sbi->s_dev, GFP_KERNEL);
1278         if (unlikely(!or)) {
1279                 EXOFS_ERR("exofs_delete_inode: osd_start_request failed\n");
1280                 return;
1281         }
1282
1283         osd_req_remove_object(or, &obj);
1284
1285         /* if we are deleting an obj that hasn't been created yet, wait */
1286         if (!obj_created(oi)) {
1287                 BUG_ON(!obj_2bcreated(oi));
1288                 wait_event(oi->i_wq, obj_created(oi));
1289         }
1290
1291         ret = exofs_async_op(or, delete_done, sbi, oi->i_cred);
1292         if (ret) {
1293                 EXOFS_ERR(
1294                        "ERROR: @exofs_delete_inode exofs_async_op failed\n");
1295                 osd_end_request(or);
1296                 return;
1297         }
1298         atomic_inc(&sbi->s_curr_pending);
1299
1300         return;
1301
1302 no_delete:
1303         clear_inode(inode);
1304 }