fs/ocfs2/aops.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public
  17  * License along with this program; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 021110-1307, USA.
  20  */
  21
  22 #include <linux/fs.h>
  23 #include <linux/slab.h>
  24 #include <linux/highmem.h>
  25 #include <linux/pagemap.h>
  26 #include <asm/byteorder.h>
  27 #include <linux/swap.h>
  28 #include <linux/pipe_fs_i.h>
  29 #include <linux/mpage.h>
  30 #include <linux/quotaops.h>
  31
  32 #include <cluster/masklog.h>
  33
  34 #include "ocfs2.h"
  35
  36 #include "alloc.h"
  37 #include "aops.h"
  38 #include "dlmglue.h"
  39 #include "extent_map.h"
  40 #include "file.h"
  41 #include "inode.h"
  42 #include "journal.h"
  43 #include "suballoc.h"
  44 #include "super.h"
  45 #include "symlink.h"
  46 #include "refcounttree.h"
  47 #include "ocfs2_trace.h"
  48
  49 #include "buffer_head_io.h"
  50
  51 static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
  52                                    struct buffer_head *bh_result, int create)
  53 {
  54         int err = -EIO;
  55         int status;
  56         struct ocfs2_dinode *fe = NULL;
  57         struct buffer_head *bh = NULL;
  58         struct buffer_head *buffer_cache_bh = NULL;
  59         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  60         void *kaddr;
  61
  62         trace_ocfs2_symlink_get_block(
  63                         (unsigned long long)OCFS2_I(inode)->ip_blkno,
  64                         (unsigned long long)iblock, bh_result, create);
  65
  66         BUG_ON(ocfs2_inode_is_fast_symlink(inode));
  67
  68         if ((iblock << inode->i_sb->s_blocksize_bits) > PATH_MAX + 1) {
  69                 mlog(ML_ERROR, "block offset > PATH_MAX: %llu",
  70                      (unsigned long long)iblock);
  71                 goto bail;
  72         }
  73
  74         status = ocfs2_read_inode_block(inode, &bh);
  75         if (status < 0) {
  76                 mlog_errno(status);
  77                 goto bail;
  78         }
  79         fe = (struct ocfs2_dinode *) bh->b_data;
  80
  81         if ((u64)iblock >= ocfs2_clusters_to_blocks(inode->i_sb,
  82                                                     le32_to_cpu(fe->i_clusters))) {
  83                 err = -ENOMEM;
  84                 mlog(ML_ERROR, "block offset is outside the allocated size: "
  85                      "%llu\n", (unsigned long long)iblock);
  86                 goto bail;
  87         }
  88
  89         /* We don't use the page cache to create symlink data, so if
  90          * need be, copy it over from the buffer cache. */
  91         if (!buffer_uptodate(bh_result) && ocfs2_inode_is_new(inode)) {
  92                 u64 blkno = le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) +
  93                             iblock;
  94                 buffer_cache_bh = sb_getblk(osb->sb, blkno);
  95                 if (!buffer_cache_bh) {
  96                         err = -ENOMEM;
  97                         mlog(ML_ERROR, "couldn't getblock for symlink!\n");
  98                         goto bail;
  99                 }
 100
 101                 /* we haven't locked out transactions, so a commit
 102                  * could've happened. Since we've got a reference on
 103                  * the bh, even if it commits while we're doing the
 104                  * copy, the data is still good. */
 105                 if (buffer_jbd(buffer_cache_bh)
 106                     && ocfs2_inode_is_new(inode)) {
 107                         kaddr = kmap_atomic(bh_result->b_page);
 108                         if (!kaddr) {
 109                                 mlog(ML_ERROR, "couldn't kmap!\n");
 110                                 goto bail;
 111                         }
 112                         memcpy(kaddr + (bh_result->b_size * iblock),
 113                                buffer_cache_bh->b_data,
 114                                bh_result->b_size);
 115                         kunmap_atomic(kaddr);
 116                         set_buffer_uptodate(bh_result);
 117                 }
 118                 brelse(buffer_cache_bh);
 119         }
 120
 121         map_bh(bh_result, inode->i_sb,
 122                le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + iblock);
 123
 124         err = 0;
 125
 126 bail:
 127         brelse(bh);
 128
 129         return err;
 130 }
 131
 132 int ocfs2_get_block(struct inode *inode, sector_t iblock,
 133                     struct buffer_head *bh_result, int create)
 134 {
 135         int err = 0;
 136         unsigned int ext_flags;
 137         u64 max_blocks = bh_result->b_size >> inode->i_blkbits;
 138         u64 p_blkno, count, past_eof;
 139         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 140
 141         trace_ocfs2_get_block((unsigned long long)OCFS2_I(inode)->ip_blkno,
 142                               (unsigned long long)iblock, bh_result, create);
 143
 144         if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
 145                 mlog(ML_NOTICE, "get_block on system inode 0x%p (%lu)\n",
 146                      inode, inode->i_ino);
 147
 148         if (S_ISLNK(inode->i_mode)) {
 149                 /* this always does I/O for some reason. */
 150                 err = ocfs2_symlink_get_block(inode, iblock, bh_result, create);
 151                 goto bail;
 152         }
 153
 154         err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, &count,
 155                                           &ext_flags);
 156         if (err) {
 157                 mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, "
 158                      "%llu, NULL)\n", err, inode, (unsigned long long)iblock,
 159                      (unsigned long long)p_blkno);
 160                 goto bail;
 161         }
 162
 163         if (max_blocks < count)
 164                 count = max_blocks;
 165
 166         /*
 167          * ocfs2 never allocates in this function - the only time we
 168          * need to use BH_New is when we're extending i_size on a file
 169          * system which doesn't support holes, in which case BH_New
 170          * allows __block_write_begin() to zero.
 171          *
 172          * If we see this on a sparse file system, then a truncate has
 173          * raced us and removed the cluster. In this case, we clear
 174          * the buffers dirty and uptodate bits and let the buffer code
 175          * ignore it as a hole.
 176          */
 177         if (create && p_blkno == 0 && ocfs2_sparse_alloc(osb)) {
 178                 clear_buffer_dirty(bh_result);
 179                 clear_buffer_uptodate(bh_result);
 180                 goto bail;
 181         }
 182
 183         /* Treat the unwritten extent as a hole for zeroing purposes. */
 184         if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
 185                 map_bh(bh_result, inode->i_sb, p_blkno);
 186
 187         bh_result->b_size = count << inode->i_blkbits;
 188
 189         if (!ocfs2_sparse_alloc(osb)) {
 190                 if (p_blkno == 0) {
 191                         err = -EIO;
 192                         mlog(ML_ERROR,
 193                              "iblock = %llu p_blkno = %llu blkno=(%llu)\n",
 194                              (unsigned long long)iblock,
 195                              (unsigned long long)p_blkno,
 196                              (unsigned long long)OCFS2_I(inode)->ip_blkno);
 197                         mlog(ML_ERROR, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode), OCFS2_I(inode)->ip_clusters);
 198                         dump_stack();
 199                         goto bail;
 200                 }
 201         }
 202
 203         past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
 204
 205         trace_ocfs2_get_block_end((unsigned long long)OCFS2_I(inode)->ip_blkno,
 206                                   (unsigned long long)past_eof);
 207         if (create && (iblock >= past_eof))
 208                 set_buffer_new(bh_result);
 209
 210 bail:
 211         if (err < 0)
 212                 err = -EIO;
 213
 214         return err;
 215 }
 216
 217 int ocfs2_read_inline_data(struct inode *inode, struct page *page,
 218                            struct buffer_head *di_bh)
 219 {
 220         void *kaddr;
 221         loff_t size;
 222         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 223
 224         if (!(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)) {
 225                 ocfs2_error(inode->i_sb, "Inode %llu lost inline data flag",
 226                             (unsigned long long)OCFS2_I(inode)->ip_blkno);
 227                 return -EROFS;
 228         }
 229
 230         size = i_size_read(inode);
 231
 232         if (size > PAGE_CACHE_SIZE ||
 233             size > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) {
 234                 ocfs2_error(inode->i_sb,
 235                             "Inode %llu has with inline data has bad size: %Lu",
 236                             (unsigned long long)OCFS2_I(inode)->ip_blkno,
 237                             (unsigned long long)size);
 238                 return -EROFS;
 239         }
 240
 241         kaddr = kmap_atomic(page);
 242         if (size)
 243                 memcpy(kaddr, di->id2.i_data.id_data, size);
 244         /* Clear the remaining part of the page */
 245         memset(kaddr + size, 0, PAGE_CACHE_SIZE - size);
 246         flush_dcache_page(page);
 247         kunmap_atomic(kaddr);
 248
 249         SetPageUptodate(page);
 250
 251         return 0;
 252 }
 253
 254 static int ocfs2_readpage_inline(struct inode *inode, struct page *page)
 255 {
 256         int ret;
 257         struct buffer_head *di_bh = NULL;
 258
 259         BUG_ON(!PageLocked(page));
 260         BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL));
 261
 262         ret = ocfs2_read_inode_block(inode, &di_bh);
 263         if (ret) {
 264                 mlog_errno(ret);
 265                 goto out;
 266         }
 267
 268         ret = ocfs2_read_inline_data(inode, page, di_bh);
 269 out:
 270         unlock_page(page);
 271
 272         brelse(di_bh);
 273         return ret;
 274 }
 275
 276 static int ocfs2_readpage(struct file *file, struct page *page)
 277 {
 278         struct inode *inode = page->mapping->host;
 279         struct ocfs2_inode_info *oi = OCFS2_I(inode);
 280         loff_t start = (loff_t)page->index << PAGE_CACHE_SHIFT;
 281         int ret, unlock = 1;
 282
 283         trace_ocfs2_readpage((unsigned long long)oi->ip_blkno,
 284                              (page ? page->index : 0));
 285
 286         ret = ocfs2_inode_lock_with_page(inode, NULL, 0, page);
 287         if (ret != 0) {
 288                 if (ret == AOP_TRUNCATED_PAGE)
 289                         unlock = 0;
 290                 mlog_errno(ret);
 291                 goto out;
 292         }
 293
 294         if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
 295                 /*
 296                  * Unlock the page and cycle ip_alloc_sem so that we don't
 297                  * busyloop waiting for ip_alloc_sem to unlock
 298                  */
 299                 ret = AOP_TRUNCATED_PAGE;
 300                 unlock_page(page);
 301                 unlock = 0;
 302                 down_read(&oi->ip_alloc_sem);
 303                 up_read(&oi->ip_alloc_sem);
 304                 goto out_inode_unlock;
 305         }
 306
 307         /*
 308          * i_size might have just been updated as we grabed the meta lock.  We
 309          * might now be discovering a truncate that hit on another node.
 310          * block_read_full_page->get_block freaks out if it is asked to read
 311          * beyond the end of a file, so we check here.  Callers
 312          * (generic_file_read, vm_ops->fault) are clever enough to check i_size
 313          * and notice that the page they just read isn't needed.
 314          *
 315          * XXX sys_readahead() seems to get that wrong?
 316          */
 317         if (start >= i_size_read(inode)) {
 318                 zero_user(page, 0, PAGE_SIZE);
 319                 SetPageUptodate(page);
 320                 ret = 0;
 321                 goto out_alloc;
 322         }
 323
 324         if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 325                 ret = ocfs2_readpage_inline(inode, page);
 326         else
 327                 ret = block_read_full_page(page, ocfs2_get_block);
 328         unlock = 0;
 329
 330 out_alloc:
 331         up_read(&OCFS2_I(inode)->ip_alloc_sem);
 332 out_inode_unlock:
 333         ocfs2_inode_unlock(inode, 0);
 334 out:
 335         if (unlock)
 336                 unlock_page(page);
 337         return ret;
 338 }
 339
 340 /*
 341  * This is used only for read-ahead. Failures or difficult to handle
 342  * situations are safe to ignore.
 343  *
 344  * Right now, we don't bother with BH_Boundary - in-inode extent lists
 345  * are quite large (243 extents on 4k blocks), so most inodes don't
 346  * grow out to a tree. If need be, detecting boundary extents could
 347  * trivially be added in a future version of ocfs2_get_block().
 348  */
 349 static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
 350                            struct list_head *pages, unsigned nr_pages)
 351 {
 352         int ret, err = -EIO;
 353         struct inode *inode = mapping->host;
 354         struct ocfs2_inode_info *oi = OCFS2_I(inode);
 355         loff_t start;
 356         struct page *last;
 357
 358         /*
 359          * Use the nonblocking flag for the dlm code to avoid page
 360          * lock inversion, but don't bother with retrying.
 361          */
 362         ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK);
 363         if (ret)
 364                 return err;
 365
 366         if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
 367                 ocfs2_inode_unlock(inode, 0);
 368                 return err;
 369         }
 370
 371         /*
 372          * Don't bother with inline-data. There isn't anything
 373          * to read-ahead in that case anyway...
 374          */
 375         if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 376                 goto out_unlock;
 377
 378         /*
 379          * Check whether a remote node truncated this file - we just
 380          * drop out in that case as it's not worth handling here.
 381          */
 382         last = list_entry(pages->prev, struct page, lru);
 383         start = (loff_t)last->index << PAGE_CACHE_SHIFT;
 384         if (start >= i_size_read(inode))
 385                 goto out_unlock;
 386
 387         err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block);
 388
 389 out_unlock:
 390         up_read(&oi->ip_alloc_sem);
 391         ocfs2_inode_unlock(inode, 0);
 392
 393         return err;
 394 }
 395
 396 /* Note: Because we don't support holes, our allocation has
 397  * already happened (allocation writes zeros to the file data)
 398  * so we don't have to worry about ordered writes in
 399  * ocfs2_writepage.
 400  *
 401  * ->writepage is called during the process of invalidating the page cache
 402  * during blocked lock processing.  It can't block on any cluster locks
 403  * to during block mapping.  It's relying on the fact that the block
 404  * mapping can't have disappeared under the dirty pages that it is
 405  * being asked to write back.
 406  */
 407 static int ocfs2_writepage(struct page *page, struct writeback_control *wbc)
 408 {
 409         trace_ocfs2_writepage(
 410                 (unsigned long long)OCFS2_I(page->mapping->host)->ip_blkno,
 411                 page->index);
 412
 413         return block_write_full_page(page, ocfs2_get_block, wbc);
 414 }
 415
 416 /* Taken from ext3. We don't necessarily need the full blown
 417  * functionality yet, but IMHO it's better to cut and paste the whole
 418  * thing so we can avoid introducing our own bugs (and easily pick up
 419  * their fixes when they happen) --Mark */
 420 int walk_page_buffers(  handle_t *handle,
 421                         struct buffer_head *head,
 422                         unsigned from,
 423                         unsigned to,
 424                         int *partial,
 425                         int (*fn)(      handle_t *handle,
 426                                         struct buffer_head *bh))
 427 {
 428         struct buffer_head *bh;
 429         unsigned block_start, block_end;
 430         unsigned blocksize = head->b_size;
 431         int err, ret = 0;
 432         struct buffer_head *next;
 433
 434         for (   bh = head, block_start = 0;
 435                 ret == 0 && (bh != head || !block_start);
 436                 block_start = block_end, bh = next)
 437         {
 438                 next = bh->b_this_page;
 439                 block_end = block_start + blocksize;
 440                 if (block_end <= from || block_start >= to) {
 441                         if (partial && !buffer_uptodate(bh))
 442                                 *partial = 1;
 443                         continue;
 444                 }
 445                 err = (*fn)(handle, bh);
 446                 if (!ret)
 447                         ret = err;
 448         }
 449         return ret;
 450 }
 451
 452 static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
 453 {
 454         sector_t status;
 455         u64 p_blkno = 0;
 456         int err = 0;
 457         struct inode *inode = mapping->host;
 458
 459         trace_ocfs2_bmap((unsigned long long)OCFS2_I(inode)->ip_blkno,
 460                          (unsigned long long)block);
 461
 462         /* We don't need to lock journal system files, since they aren't
 463          * accessed concurrently from multiple nodes.
 464          */
 465         if (!INODE_JOURNAL(inode)) {
 466                 err = ocfs2_inode_lock(inode, NULL, 0);
 467                 if (err) {
 468                         if (err != -ENOENT)
 469                                 mlog_errno(err);
 470                         goto bail;
 471                 }
 472                 down_read(&OCFS2_I(inode)->ip_alloc_sem);
 473         }
 474
 475         if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
 476                 err = ocfs2_extent_map_get_blocks(inode, block, &p_blkno, NULL,
 477                                                   NULL);
 478
 479         if (!INODE_JOURNAL(inode)) {
 480                 up_read(&OCFS2_I(inode)->ip_alloc_sem);
 481                 ocfs2_inode_unlock(inode, 0);
 482         }
 483
 484         if (err) {
 485                 mlog(ML_ERROR, "get_blocks() failed, block = %llu\n",
 486                      (unsigned long long)block);
 487                 mlog_errno(err);
 488                 goto bail;
 489         }
 490
 491 bail:
 492         status = err ? 0 : p_blkno;
 493
 494         return status;
 495 }
 496
 497 /*
 498  * TODO: Make this into a generic get_blocks function.
 499  *
 500  * From do_direct_io in direct-io.c:
 501  *  "So what we do is to permit the ->get_blocks function to populate
 502  *   bh.b_size with the size of IO which is permitted at this offset and
 503  *   this i_blkbits."
 504  *
 505  * This function is called directly from get_more_blocks in direct-io.c.
 506  *
 507  * called like this: dio->get_blocks(dio->inode, fs_startblk,
 508  *                                      fs_count, map_bh, dio->rw == WRITE);
 509  *
 510  * Note that we never bother to allocate blocks here, and thus ignore the
 511  * create argument.
 512  */
 513 static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
 514                                      struct buffer_head *bh_result, int create)
 515 {
 516         int ret;
 517         u64 p_blkno, inode_blocks, contig_blocks;
 518         unsigned int ext_flags;
 519         unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
 520         unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
 521
 522         /* This function won't even be called if the request isn't all
 523          * nicely aligned and of the right size, so there's no need
 524          * for us to check any of that. */
 525
 526         inode_blocks = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
 527
 528         /* This figures out the size of the next contiguous block, and
 529          * our logical offset */
 530         ret = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno,
 531                                           &contig_blocks, &ext_flags);
 532         if (ret) {
 533                 mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n",
 534                      (unsigned long long)iblock);
 535                 ret = -EIO;
 536                 goto bail;
 537         }
 538
 539         /* We should already CoW the refcounted extent in case of create. */
 540         BUG_ON(create && (ext_flags & OCFS2_EXT_REFCOUNTED));
 541
 542         /*
 543          * get_more_blocks() expects us to describe a hole by clearing
 544          * the mapped bit on bh_result().
 545          *
 546          * Consider an unwritten extent as a hole.
 547          */
 548         if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
 549                 map_bh(bh_result, inode->i_sb, p_blkno);
 550         else
 551                 clear_buffer_mapped(bh_result);
 552
 553         /* make sure we don't map more than max_blocks blocks here as
 554            that's all the kernel will handle at this point. */
 555         if (max_blocks < contig_blocks)
 556                 contig_blocks = max_blocks;
 557         bh_result->b_size = contig_blocks << blocksize_bits;
 558 bail:
 559         return ret;
 560 }
 561
 562 /*
 563  * ocfs2_dio_end_io is called by the dio core when a dio is finished.  We're
 564  * particularly interested in the aio/dio case.  We use the rw_lock DLM lock
 565  * to protect io on one node from truncation on another.
 566  */
 567 static void ocfs2_dio_end_io(struct kiocb *iocb,
 568                              loff_t offset,
 569                              ssize_t bytes,
 570                              void *private)
 571 {
 572         struct inode *inode = file_inode(iocb->ki_filp);
 573         int level;
 574
 575         /* this io's submitter should not have unlocked this before we could */
 576         BUG_ON(!ocfs2_iocb_is_rw_locked(iocb));
 577
 578         if (ocfs2_iocb_is_sem_locked(iocb))
 579                 ocfs2_iocb_clear_sem_locked(iocb);
 580
 581         if (ocfs2_iocb_is_unaligned_aio(iocb)) {
 582                 ocfs2_iocb_clear_unaligned_aio(iocb);
 583
 584                 mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);
 585         }
 586
 587         ocfs2_iocb_clear_rw_locked(iocb);
 588
 589         level = ocfs2_iocb_rw_locked_level(iocb);
 590         ocfs2_rw_unlock(inode, level);
 591 }
 592
 593 static int ocfs2_releasepage(struct page *page, gfp_t wait)
 594 {
 595         if (!page_has_buffers(page))
 596                 return 0;
 597         return try_to_free_buffers(page);
 598 }
 599
 600 static ssize_t ocfs2_direct_IO(int rw,
 601                                struct kiocb *iocb,
 602                                const struct iovec *iov,
 603                                loff_t offset,
 604                                unsigned long nr_segs)
 605 {
 606         struct file *file = iocb->ki_filp;
 607         struct inode *inode = file_inode(file)->i_mapping->host;
 608
 609         /*
 610          * Fallback to buffered I/O if we see an inode without
 611          * extents.
 612          */
 613         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 614                 return 0;
 615
 616         /* Fallback to buffered I/O if we are appending. */
 617         if (i_size_read(inode) <= offset)
 618                 return 0;
 619
 620         return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev,
 621                                     iov, offset, nr_segs,
 622                                     ocfs2_direct_IO_get_blocks,
 623                                     ocfs2_dio_end_io, NULL, 0);
 624 }
 625
 626 static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
 627                                             u32 cpos,
 628                                             unsigned int *start,
 629                                             unsigned int *end)
 630 {
 631         unsigned int cluster_start = 0, cluster_end = PAGE_CACHE_SIZE;
 632
 633         if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) {
 634                 unsigned int cpp;
 635
 636                 cpp = 1 << (PAGE_CACHE_SHIFT - osb->s_clustersize_bits);
 637
 638                 cluster_start = cpos % cpp;
 639                 cluster_start = cluster_start << osb->s_clustersize_bits;
 640
 641                 cluster_end = cluster_start + osb->s_clustersize;
 642         }
 643
 644         BUG_ON(cluster_start > PAGE_SIZE);
 645         BUG_ON(cluster_end > PAGE_SIZE);
 646
 647         if (start)
 648                 *start = cluster_start;
 649         if (end)
 650                 *end = cluster_end;
 651 }
 652
 653 /*
 654  * 'from' and 'to' are the region in the page to avoid zeroing.
 655  *
 656  * If pagesize > clustersize, this function will avoid zeroing outside
 657  * of the cluster boundary.
 658  *
 659  * from == to == 0 is code for "zero the entire cluster region"
 660  */
 661 static void ocfs2_clear_page_regions(struct page *page,
 662                                      struct ocfs2_super *osb, u32 cpos,
 663                                      unsigned from, unsigned to)
 664 {
 665         void *kaddr;
 666         unsigned int cluster_start, cluster_end;
 667
 668         ocfs2_figure_cluster_boundaries(osb, cpos, &cluster_start, &cluster_end);
 669
 670         kaddr = kmap_atomic(page);
 671
 672         if (from || to) {
 673                 if (from > cluster_start)
 674                         memset(kaddr + cluster_start, 0, from - cluster_start);
 675                 if (to < cluster_end)
 676                         memset(kaddr + to, 0, cluster_end - to);
 677         } else {
 678                 memset(kaddr + cluster_start, 0, cluster_end - cluster_start);
 679         }
 680
 681         kunmap_atomic(kaddr);
 682 }
 683
 684 /*
 685  * Nonsparse file systems fully allocate before we get to the write
 686  * code. This prevents ocfs2_write() from tagging the write as an
 687  * allocating one, which means ocfs2_map_page_blocks() might try to
 688  * read-in the blocks at the tail of our file. Avoid reading them by
 689  * testing i_size against each block offset.
 690  */
 691 static int ocfs2_should_read_blk(struct inode *inode, struct page *page,
 692                                  unsigned int block_start)
 693 {
 694         u64 offset = page_offset(page) + block_start;
 695
 696         if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
 697                 return 1;
 698
 699         if (i_size_read(inode) > offset)
 700                 return 1;
 701
 702         return 0;
 703 }
 704
 705 /*
 706  * Some of this taken from __block_write_begin(). We already have our
 707  * mapping by now though, and the entire write will be allocating or
 708  * it won't, so not much need to use BH_New.
 709  *
 710  * This will also skip zeroing, which is handled externally.
 711  */
 712 int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
 713                           struct inode *inode, unsigned int from,
 714                           unsigned int to, int new)
 715 {
 716         int ret = 0;
 717         struct buffer_head *head, *bh, *wait[2], **wait_bh = wait;
 718         unsigned int block_end, block_start;
 719         unsigned int bsize = 1 << inode->i_blkbits;
 720
 721         if (!page_has_buffers(page))
 722                 create_empty_buffers(page, bsize, 0);
 723
 724         head = page_buffers(page);
 725         for (bh = head, block_start = 0; bh != head || !block_start;
 726              bh = bh->b_this_page, block_start += bsize) {
 727                 block_end = block_start + bsize;
 728
 729                 clear_buffer_new(bh);
 730
 731                 /*
 732                  * Ignore blocks outside of our i/o range -
 733                  * they may belong to unallocated clusters.
 734                  */
 735                 if (block_start >= to || block_end <= from) {
 736                         if (PageUptodate(page))
 737                                 set_buffer_uptodate(bh);
 738                         continue;
 739                 }
 740
 741                 /*
 742                  * For an allocating write with cluster size >= page
 743                  * size, we always write the entire page.
 744                  */
 745                 if (new)
 746                         set_buffer_new(bh);
 747
 748                 if (!buffer_mapped(bh)) {
 749                         map_bh(bh, inode->i_sb, *p_blkno);
 750                         unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
 751                 }
 752
 753                 if (PageUptodate(page)) {
 754                         if (!buffer_uptodate(bh))
 755                                 set_buffer_uptodate(bh);
 756                 } else if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
 757                            !buffer_new(bh) &&
 758                            ocfs2_should_read_blk(inode, page, block_start) &&
 759                            (block_start < from || block_end > to)) {
 760                         ll_rw_block(READ, 1, &bh);
 761                         *wait_bh++=bh;
 762                 }
 763
 764                 *p_blkno = *p_blkno + 1;
 765         }
 766
 767         /*
 768          * If we issued read requests - let them complete.
 769          */
 770         while(wait_bh > wait) {
 771                 wait_on_buffer(*--wait_bh);
 772                 if (!buffer_uptodate(*wait_bh))
 773                         ret = -EIO;
 774         }
 775
 776         if (ret == 0 || !new)
 777                 return ret;
 778
 779         /*
 780          * If we get -EIO above, zero out any newly allocated blocks
 781          * to avoid exposing stale data.
 782          */
 783         bh = head;
 784         block_start = 0;
 785         do {
 786                 block_end = block_start + bsize;
 787                 if (block_end <= from)
 788                         goto next_bh;
 789                 if (block_start >= to)
 790                         break;
 791
 792                 zero_user(page, block_start, bh->b_size);
 793                 set_buffer_uptodate(bh);
 794                 mark_buffer_dirty(bh);
 795
 796 next_bh:
 797                 block_start = block_end;
 798                 bh = bh->b_this_page;
 799         } while (bh != head);
 800
 801         return ret;
 802 }
 803
 804 #if (PAGE_CACHE_SIZE >= OCFS2_MAX_CLUSTERSIZE)
 805 #define OCFS2_MAX_CTXT_PAGES    1
 806 #else
 807 #define OCFS2_MAX_CTXT_PAGES    (OCFS2_MAX_CLUSTERSIZE / PAGE_CACHE_SIZE)
 808 #endif
 809
 810 #define OCFS2_MAX_CLUSTERS_PER_PAGE     (PAGE_CACHE_SIZE / OCFS2_MIN_CLUSTERSIZE)
 811
 812 /*
 813  * Describe the state of a single cluster to be written to.
 814  */
 815 struct ocfs2_write_cluster_desc {
 816         u32             c_cpos;
 817         u32             c_phys;
 818         /*
 819          * Give this a unique field because c_phys eventually gets
 820          * filled.
 821          */
 822         unsigned        c_new;
 823         unsigned        c_unwritten;
 824         unsigned        c_needs_zero;
 825 };
 826
 827 struct ocfs2_write_ctxt {
 828         /* Logical cluster position / len of write */
 829         u32                             w_cpos;
 830         u32                             w_clen;
 831
 832         /* First cluster allocated in a nonsparse extend */
 833         u32                             w_first_new_cpos;
 834
 835         struct ocfs2_write_cluster_desc w_desc[OCFS2_MAX_CLUSTERS_PER_PAGE];
 836
 837         /*
 838          * This is true if page_size > cluster_size.
 839          *
 840          * It triggers a set of special cases during write which might
 841          * have to deal with allocating writes to partial pages.
 842          */
 843         unsigned int                    w_large_pages;
 844
 845         /*
 846          * Pages involved in this write.
 847          *
 848          * w_target_page is the page being written to by the user.
 849          *
 850          * w_pages is an array of pages which always contains
 851          * w_target_page, and in the case of an allocating write with
 852          * page_size < cluster size, it will contain zero'd and mapped
 853          * pages adjacent to w_target_page which need to be written
 854          * out in so that future reads from that region will get
 855          * zero's.
 856          */
 857         unsigned int                    w_num_pages;
 858         struct page                     *w_pages[OCFS2_MAX_CTXT_PAGES];
 859         struct page                     *w_target_page;
 860
 861         /*
 862          * w_target_locked is used for page_mkwrite path indicating no unlocking
 863          * against w_target_page in ocfs2_write_end_nolock.
 864          */
 865         unsigned int                    w_target_locked:1;
 866
 867         /*
 868          * ocfs2_write_end() uses this to know what the real range to
 869          * write in the target should be.
 870          */
 871         unsigned int                    w_target_from;
 872         unsigned int                    w_target_to;
 873
 874         /*
 875          * We could use journal_current_handle() but this is cleaner,
 876          * IMHO -Mark
 877          */
 878         handle_t                        *w_handle;
 879
 880         struct buffer_head              *w_di_bh;
 881
 882         struct ocfs2_cached_dealloc_ctxt w_dealloc;
 883 };
 884
 885 void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
 886 {
 887         int i;
 888
 889         for(i = 0; i < num_pages; i++) {
 890                 if (pages[i]) {
 891                         unlock_page(pages[i]);
 892                         mark_page_accessed(pages[i]);
 893                         page_cache_release(pages[i]);
 894                 }
 895         }
 896 }
 897
 898 static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
 899 {
 900         int i;
 901
 902         /*
 903          * w_target_locked is only set to true in the page_mkwrite() case.
 904          * The intent is to allow us to lock the target page from write_begin()
 905          * to write_end(). The caller must hold a ref on w_target_page.
 906          */
 907         if (wc->w_target_locked) {
 908                 BUG_ON(!wc->w_target_page);
 909                 for (i = 0; i < wc->w_num_pages; i++) {
 910                         if (wc->w_target_page == wc->w_pages[i]) {
 911                                 wc->w_pages[i] = NULL;
 912                                 break;
 913                         }
 914                 }
 915                 mark_page_accessed(wc->w_target_page);
 916                 page_cache_release(wc->w_target_page);
 917         }
 918         ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
 919
 920         brelse(wc->w_di_bh);
 921         kfree(wc);
 922 }
 923
 924 static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
 925                                   struct ocfs2_super *osb, loff_t pos,
 926                                   unsigned len, struct buffer_head *di_bh)
 927 {
 928         u32 cend;
 929         struct ocfs2_write_ctxt *wc;
 930
 931         wc = kzalloc(sizeof(struct ocfs2_write_ctxt), GFP_NOFS);
 932         if (!wc)
 933                 return -ENOMEM;
 934
 935         wc->w_cpos = pos >> osb->s_clustersize_bits;
 936         wc->w_first_new_cpos = UINT_MAX;
 937         cend = (pos + len - 1) >> osb->s_clustersize_bits;
 938         wc->w_clen = cend - wc->w_cpos + 1;
 939         get_bh(di_bh);
 940         wc->w_di_bh = di_bh;
 941
 942         if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))
 943                 wc->w_large_pages = 1;
 944         else
 945                 wc->w_large_pages = 0;
 946
 947         ocfs2_init_dealloc_ctxt(&wc->w_dealloc);
 948
 949         *wcp = wc;
 950
 951         return 0;
 952 }
 953
 954 /*
 955  * If a page has any new buffers, zero them out here, and mark them uptodate
 956  * and dirty so they'll be written out (in order to prevent uninitialised
 957  * block data from leaking). And clear the new bit.
 958  */
 959 static void ocfs2_zero_new_buffers(struct page *page, unsigned from, unsigned to)
 960 {
 961         unsigned int block_start, block_end;
 962         struct buffer_head *head, *bh;
 963
 964         BUG_ON(!PageLocked(page));
 965         if (!page_has_buffers(page))
 966                 return;
 967
 968         bh = head = page_buffers(page);
 969         block_start = 0;
 970         do {
 971                 block_end = block_start + bh->b_size;
 972
 973                 if (buffer_new(bh)) {
 974                         if (block_end > from && block_start < to) {
 975                                 if (!PageUptodate(page)) {
 976                                         unsigned start, end;
 977
 978                                         start = max(from, block_start);
 979                                         end = min(to, block_end);
 980
 981                                         zero_user_segment(page, start, end);
 982                                         set_buffer_uptodate(bh);
 983                                 }
 984
 985                                 clear_buffer_new(bh);
 986                                 mark_buffer_dirty(bh);
 987                         }
 988                 }
 989
 990                 block_start = block_end;
 991                 bh = bh->b_this_page;
 992         } while (bh != head);
 993 }
 994
 995 /*
 996  * Only called when we have a failure during allocating write to write
 997  * zero's to the newly allocated region.
 998  */
 999 static void ocfs2_write_failure(struct inode *inode,
1000                                 struct ocfs2_write_ctxt *wc,
1001                                 loff_t user_pos, unsigned user_len)
1002 {
1003         int i;
1004         unsigned from = user_pos & (PAGE_CACHE_SIZE - 1),
1005                 to = user_pos + user_len;
1006         struct page *tmppage;
1007
1008         ocfs2_zero_new_buffers(wc->w_target_page, from, to);
1009
1010         for(i = 0; i < wc->w_num_pages; i++) {
1011                 tmppage = wc->w_pages[i];
1012
1013                 if (page_has_buffers(tmppage)) {
1014                         if (ocfs2_should_order_data(inode))
1015                                 ocfs2_jbd2_file_inode(wc->w_handle, inode);
1016
1017                         block_commit_write(tmppage, from, to);
1018                 }
1019         }
1020 }
1021
1022 static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno,
1023                                         struct ocfs2_write_ctxt *wc,
1024                                         struct page *page, u32 cpos,
1025                                         loff_t user_pos, unsigned user_len,
1026                                         int new)
1027 {
1028         int ret;
1029         unsigned int map_from = 0, map_to = 0;
1030         unsigned int cluster_start, cluster_end;
1031         unsigned int user_data_from = 0, user_data_to = 0;
1032
1033         ocfs2_figure_cluster_boundaries(OCFS2_SB(inode->i_sb), cpos,
1034                                         &cluster_start, &cluster_end);
1035
1036         /* treat the write as new if the a hole/lseek spanned across
1037          * the page boundary.
1038          */
1039         new = new | ((i_size_read(inode) <= page_offset(page)) &&
1040                         (page_offset(page) <= user_pos));
1041
1042         if (page == wc->w_target_page) {
1043                 map_from = user_pos & (PAGE_CACHE_SIZE - 1);
1044                 map_to = map_from + user_len;
1045
1046                 if (new)
1047                         ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1048                                                     cluster_start, cluster_end,
1049                                                     new);
1050                 else
1051                         ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1052                                                     map_from, map_to, new);
1053                 if (ret) {
1054                         mlog_errno(ret);
1055                         goto out;
1056                 }
1057
1058                 user_data_from = map_from;
1059                 user_data_to = map_to;
1060                 if (new) {
1061                         map_from = cluster_start;
1062                         map_to = cluster_end;
1063                 }
1064         } else {
1065                 /*
1066                  * If we haven't allocated the new page yet, we
1067                  * shouldn't be writing it out without copying user
1068                  * data. This is likely a math error from the caller.
1069                  */
1070                 BUG_ON(!new);
1071
1072                 map_from = cluster_start;
1073                 map_to = cluster_end;
1074
1075                 ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1076                                             cluster_start, cluster_end, new);
1077                 if (ret) {
1078                         mlog_errno(ret);
1079                         goto out;
1080                 }
1081         }
1082
1083         /*
1084          * Parts of newly allocated pages need to be zero'd.
1085          *
1086          * Above, we have also rewritten 'to' and 'from' - as far as
1087          * the rest of the function is concerned, the entire cluster
1088          * range inside of a page needs to be written.
1089          *
1090          * We can skip this if the page is up to date - it's already
1091          * been zero'd from being read in as a hole.
1092          */
1093         if (new && !PageUptodate(page))
1094                 ocfs2_clear_page_regions(page, OCFS2_SB(inode->i_sb),
1095                                          cpos, user_data_from, user_data_to);
1096
1097         flush_dcache_page(page);
1098
1099 out:
1100         return ret;
1101 }
1102
1103 /*
1104  * This function will only grab one clusters worth of pages.
1105  */
1106 static int ocfs2_grab_pages_for_write(struct address_space *mapping,
1107                                       struct ocfs2_write_ctxt *wc,
1108                                       u32 cpos, loff_t user_pos,
1109                                       unsigned user_len, int new,
1110                                       struct page *mmap_page)
1111 {
1112         int ret = 0, i;
1113         unsigned long start, target_index, end_index, index;
1114         struct inode *inode = mapping->host;
1115         loff_t last_byte;
1116
1117         target_index = user_pos >> PAGE_CACHE_SHIFT;
1118
1119         /*
1120          * Figure out how many pages we'll be manipulating here. For
1121          * non allocating write, we just change the one
1122          * page. Otherwise, we'll need a whole clusters worth.  If we're
1123          * writing past i_size, we only need enough pages to cover the
1124          * last page of the write.
1125          */
1126         if (new) {
1127                 wc->w_num_pages = ocfs2_pages_per_cluster(inode->i_sb);
1128                 start = ocfs2_align_clusters_to_page_index(inode->i_sb, cpos);
1129                 /*
1130                  * We need the index *past* the last page we could possibly
1131                  * touch.  This is the page past the end of the write or
1132                  * i_size, whichever is greater.
1133                  */
1134                 last_byte = max(user_pos + user_len, i_size_read(inode));
1135                 BUG_ON(last_byte < 1);
1136                 end_index = ((last_byte - 1) >> PAGE_CACHE_SHIFT) + 1;
1137                 if ((start + wc->w_num_pages) > end_index)
1138                         wc->w_num_pages = end_index - start;
1139         } else {
1140                 wc->w_num_pages = 1;
1141                 start = target_index;
1142         }
1143
1144         for(i = 0; i < wc->w_num_pages; i++) {
1145                 index = start + i;
1146
1147                 if (index == target_index && mmap_page) {
1148                         /*
1149                          * ocfs2_pagemkwrite() is a little different
1150                          * and wants us to directly use the page
1151                          * passed in.
1152                          */
1153                         lock_page(mmap_page);
1154
1155                         /* Exit and let the caller retry */
1156                         if (mmap_page->mapping != mapping) {
1157                                 WARN_ON(mmap_page->mapping);
1158                                 unlock_page(mmap_page);
1159                                 ret = -EAGAIN;
1160                                 goto out;
1161                         }
1162
1163                         page_cache_get(mmap_page);
1164                         wc->w_pages[i] = mmap_page;
1165                         wc->w_target_locked = true;
1166                 } else {
1167                         wc->w_pages[i] = find_or_create_page(mapping, index,
1168                                                              GFP_NOFS);
1169                         if (!wc->w_pages[i]) {
1170                                 ret = -ENOMEM;
1171                                 mlog_errno(ret);
1172                                 goto out;
1173                         }
1174                 }
1175                 wait_for_stable_page(wc->w_pages[i]);
1176
1177                 if (index == target_index)
1178                         wc->w_target_page = wc->w_pages[i];
1179         }
1180 out:
1181         if (ret)
1182                 wc->w_target_locked = false;
1183         return ret;
1184 }
1185
1186 /*
1187  * Prepare a single cluster for write one cluster into the file.
1188  */
1189 static int ocfs2_write_cluster(struct address_space *mapping,
1190                                u32 phys, unsigned int unwritten,
1191                                unsigned int should_zero,
1192                                struct ocfs2_alloc_context *data_ac,
1193                                struct ocfs2_alloc_context *meta_ac,
1194                                struct ocfs2_write_ctxt *wc, u32 cpos,
1195                                loff_t user_pos, unsigned user_len)
1196 {
1197         int ret, i, new;
1198         u64 v_blkno, p_blkno;
1199         struct inode *inode = mapping->host;
1200         struct ocfs2_extent_tree et;
1201
1202         new = phys == 0 ? 1 : 0;
1203         if (new) {
1204                 u32 tmp_pos;
1205
1206                 /*
1207                  * This is safe to call with the page locks - it won't take
1208                  * any additional semaphores or cluster locks.
1209                  */
1210                 tmp_pos = cpos;
1211                 ret = ocfs2_add_inode_data(OCFS2_SB(inode->i_sb), inode,
1212                                            &tmp_pos, 1, 0, wc->w_di_bh,
1213                                            wc->w_handle, data_ac,
1214                                            meta_ac, NULL);
1215                 /*
1216                  * This shouldn't happen because we must have already
1217                  * calculated the correct meta data allocation required. The
1218                  * internal tree allocation code should know how to increase
1219                  * transaction credits itself.
1220                  *
1221                  * If need be, we could handle -EAGAIN for a
1222                  * RESTART_TRANS here.
1223                  */
1224                 mlog_bug_on_msg(ret == -EAGAIN,
1225                                 "Inode %llu: EAGAIN return during allocation.\n",
1226                                 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1227                 if (ret < 0) {
1228                         mlog_errno(ret);
1229                         goto out;
1230                 }
1231         } else if (unwritten) {
1232                 ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
1233                                               wc->w_di_bh);
1234                 ret = ocfs2_mark_extent_written(inode, &et,
1235                                                 wc->w_handle, cpos, 1, phys,
1236                                                 meta_ac, &wc->w_dealloc);
1237                 if (ret < 0) {
1238                         mlog_errno(ret);
1239                         goto out;
1240                 }
1241         }
1242
1243         if (should_zero)
1244                 v_blkno = ocfs2_clusters_to_blocks(inode->i_sb, cpos);
1245         else
1246                 v_blkno = user_pos >> inode->i_sb->s_blocksize_bits;
1247
1248         /*
1249          * The only reason this should fail is due to an inability to
1250          * find the extent added.
1251          */
1252         ret = ocfs2_extent_map_get_blocks(inode, v_blkno, &p_blkno, NULL,
1253                                           NULL);
1254         if (ret < 0) {
1255                 ocfs2_error(inode->i_sb, "Corrupting extend for inode %llu, "
1256                             "at logical block %llu",
1257                             (unsigned long long)OCFS2_I(inode)->ip_blkno,
1258                             (unsigned long long)v_blkno);
1259                 goto out;
1260         }
1261
1262         BUG_ON(p_blkno == 0);
1263
1264         for(i = 0; i < wc->w_num_pages; i++) {
1265                 int tmpret;
1266
1267                 tmpret = ocfs2_prepare_page_for_write(inode, &p_blkno, wc,
1268                                                       wc->w_pages[i], cpos,
1269                                                       user_pos, user_len,
1270                                                       should_zero);
1271                 if (tmpret) {
1272                         mlog_errno(tmpret);
1273                         if (ret == 0)
1274                                 ret = tmpret;
1275                 }
1276         }
1277
1278         /*
1279          * We only have cleanup to do in case of allocating write.
1280          */
1281         if (ret && new)
1282                 ocfs2_write_failure(inode, wc, user_pos, user_len);
1283
1284 out:
1285
1286         return ret;
1287 }
1288
1289 static int ocfs2_write_cluster_by_desc(struct address_space *mapping,
1290                                        struct ocfs2_alloc_context *data_ac,
1291                                        struct ocfs2_alloc_context *meta_ac,
1292                                        struct ocfs2_write_ctxt *wc,
1293                                        loff_t pos, unsigned len)
1294 {
1295         int ret, i;
1296         loff_t cluster_off;
1297         unsigned int local_len = len;
1298         struct ocfs2_write_cluster_desc *desc;
1299         struct ocfs2_super *osb = OCFS2_SB(mapping->host->i_sb);
1300
1301         for (i = 0; i < wc->w_clen; i++) {
1302                 desc = &wc->w_desc[i];
1303
1304                 /*
1305                  * We have to make sure that the total write passed in
1306                  * doesn't extend past a single cluster.
1307                  */
1308                 local_len = len;
1309                 cluster_off = pos & (osb->s_clustersize - 1);
1310                 if ((cluster_off + local_len) > osb->s_clustersize)
1311                         local_len = osb->s_clustersize - cluster_off;
1312
1313                 ret = ocfs2_write_cluster(mapping, desc->c_phys,
1314                                           desc->c_unwritten,
1315                                           desc->c_needs_zero,
1316                                           data_ac, meta_ac,
1317                                           wc, desc->c_cpos, pos, local_len);
1318                 if (ret) {
1319                         mlog_errno(ret);
1320                         goto out;
1321                 }
1322
1323                 len -= local_len;
1324                 pos += local_len;
1325         }
1326
1327         ret = 0;
1328 out:
1329         return ret;
1330 }
1331
1332 /*
1333  * ocfs2_write_end() wants to know which parts of the target page it
1334  * should complete the write on. It's easiest to compute them ahead of
1335  * time when a more complete view of the write is available.
1336  */
1337 static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
1338                                         struct ocfs2_write_ctxt *wc,
1339                                         loff_t pos, unsigned len, int alloc)
1340 {
1341         struct ocfs2_write_cluster_desc *desc;
1342
1343         wc->w_target_from = pos & (PAGE_CACHE_SIZE - 1);
1344         wc->w_target_to = wc->w_target_from + len;
1345
1346         if (alloc == 0)
1347                 return;
1348
1349         /*
1350          * Allocating write - we may have different boundaries based
1351          * on page size and cluster size.
1352          *
1353          * NOTE: We can no longer compute one value from the other as
1354          * the actual write length and user provided length may be
1355          * different.
1356          */
1357
1358         if (wc->w_large_pages) {
1359                 /*
1360                  * We only care about the 1st and last cluster within
1361                  * our range and whether they should be zero'd or not. Either
1362                  * value may be extended out to the start/end of a
1363                  * newly allocated cluster.
1364                  */
1365                 desc = &wc->w_desc[0];
1366                 if (desc->c_needs_zero)
1367                         ocfs2_figure_cluster_boundaries(osb,
1368                                                         desc->c_cpos,
1369                                                         &wc->w_target_from,
1370                                                         NULL);
1371
1372                 desc = &wc->w_desc[wc->w_clen - 1];
1373                 if (desc->c_needs_zero)
1374                         ocfs2_figure_cluster_boundaries(osb,
1375                                                         desc->c_cpos,
1376                                                         NULL,
1377                                                         &wc->w_target_to);
1378         } else {
1379                 wc->w_target_from = 0;
1380                 wc->w_target_to = PAGE_CACHE_SIZE;
1381         }
1382 }
1383
1384 /*
1385  * Populate each single-cluster write descriptor in the write context
1386  * with information about the i/o to be done.
1387  *
1388  * Returns the number of clusters that will have to be allocated, as
1389  * well as a worst case estimate of the number of extent records that
1390  * would have to be created during a write to an unwritten region.
1391  */
1392 static int ocfs2_populate_write_desc(struct inode *inode,
1393                                      struct ocfs2_write_ctxt *wc,
1394                                      unsigned int *clusters_to_alloc,
1395                                      unsigned int *extents_to_split)
1396 {
1397         int ret;
1398         struct ocfs2_write_cluster_desc *desc;
1399         unsigned int num_clusters = 0;
1400         unsigned int ext_flags = 0;
1401         u32 phys = 0;
1402         int i;
1403
1404         *clusters_to_alloc = 0;
1405         *extents_to_split = 0;
1406
1407         for (i = 0; i < wc->w_clen; i++) {
1408                 desc = &wc->w_desc[i];
1409                 desc->c_cpos = wc->w_cpos + i;
1410
1411                 if (num_clusters == 0) {
1412                         /*
1413                          * Need to look up the next extent record.
1414                          */
1415                         ret = ocfs2_get_clusters(inode, desc->c_cpos, &phys,
1416                                                  &num_clusters, &ext_flags);
1417                         if (ret) {
1418                                 mlog_errno(ret);
1419                                 goto out;
1420                         }
1421
1422                         /* We should already CoW the refcountd extent. */
1423                         BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
1424
1425                         /*
1426                          * Assume worst case - that we're writing in
1427                          * the middle of the extent.
1428                          *
1429                          * We can assume that the write proceeds from
1430                          * left to right, in which case the extent
1431                          * insert code is smart enough to coalesce the
1432                          * next splits into the previous records created.
1433                          */
1434                         if (ext_flags & OCFS2_EXT_UNWRITTEN)
1435                                 *extents_to_split = *extents_to_split + 2;
1436                 } else if (phys) {
1437                         /*
1438                          * Only increment phys if it doesn't describe
1439                          * a hole.
1440                          */
1441                         phys++;
1442                 }
1443
1444                 /*
1445                  * If w_first_new_cpos is < UINT_MAX, we have a non-sparse
1446                  * file that got extended.  w_first_new_cpos tells us
1447                  * where the newly allocated clusters are so we can
1448                  * zero them.
1449                  */
1450                 if (desc->c_cpos >= wc->w_first_new_cpos) {
1451                         BUG_ON(phys == 0);
1452                         desc->c_needs_zero = 1;
1453                 }
1454
1455                 desc->c_phys = phys;
1456                 if (phys == 0) {
1457                         desc->c_new = 1;
1458                         desc->c_needs_zero = 1;
1459                         *clusters_to_alloc = *clusters_to_alloc + 1;
1460                 }
1461
1462                 if (ext_flags & OCFS2_EXT_UNWRITTEN) {
1463                         desc->c_unwritten = 1;
1464                         desc->c_needs_zero = 1;
1465                 }
1466
1467                 num_clusters--;
1468         }
1469
1470         ret = 0;
1471 out:
1472         return ret;
1473 }
1474
1475 static int ocfs2_write_begin_inline(struct address_space *mapping,
1476                                     struct inode *inode,
1477                                     struct ocfs2_write_ctxt *wc)
1478 {
1479         int ret;
1480         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1481         struct page *page;
1482         handle_t *handle;
1483         struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1484
1485         page = find_or_create_page(mapping, 0, GFP_NOFS);
1486         if (!page) {
1487                 ret = -ENOMEM;
1488                 mlog_errno(ret);
1489                 goto out;
1490         }
1491         /*
1492          * If we don't set w_num_pages then this page won't get unlocked
1493          * and freed on cleanup of the write context.
1494          */
1495         wc->w_pages[0] = wc->w_target_page = page;
1496         wc->w_num_pages = 1;
1497
1498         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1499         if (IS_ERR(handle)) {
1500                 ret = PTR_ERR(handle);
1501                 mlog_errno(ret);
1502                 goto out;
1503         }
1504
1505         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
1506                                       OCFS2_JOURNAL_ACCESS_WRITE);
1507         if (ret) {
1508                 ocfs2_commit_trans(osb, handle);
1509
1510                 mlog_errno(ret);
1511                 goto out;
1512         }
1513
1514         if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
1515                 ocfs2_set_inode_data_inline(inode, di);
1516
1517         if (!PageUptodate(page)) {
1518                 ret = ocfs2_read_inline_data(inode, page, wc->w_di_bh);
1519                 if (ret) {
1520                         ocfs2_commit_trans(osb, handle);
1521
1522                         goto out;
1523                 }
1524         }
1525
1526         wc->w_handle = handle;
1527 out:
1528         return ret;
1529 }
1530
1531 int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size)
1532 {
1533         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1534
1535         if (new_size <= le16_to_cpu(di->id2.i_data.id_count))
1536                 return 1;
1537         return 0;
1538 }
1539
1540 static int ocfs2_try_to_write_inline_data(struct address_space *mapping,
1541                                           struct inode *inode, loff_t pos,
1542                                           unsigned len, struct page *mmap_page,
1543                                           struct ocfs2_write_ctxt *wc)
1544 {
1545         int ret, written = 0;
1546         loff_t end = pos + len;
1547         struct ocfs2_inode_info *oi = OCFS2_I(inode);
1548         struct ocfs2_dinode *di = NULL;
1549
1550         trace_ocfs2_try_to_write_inline_data((unsigned long long)oi->ip_blkno,
1551                                              len, (unsigned long long)pos,
1552                                              oi->ip_dyn_features);
1553
1554         /*
1555          * Handle inodes which already have inline data 1st.
1556          */
1557         if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1558                 if (mmap_page == NULL &&
1559                     ocfs2_size_fits_inline_data(wc->w_di_bh, end))
1560                         goto do_inline_write;
1561
1562                 /*
1563                  * The write won't fit - we have to give this inode an
1564                  * inline extent list now.
1565                  */
1566                 ret = ocfs2_convert_inline_data_to_extents(inode, wc->w_di_bh);
1567                 if (ret)
1568                         mlog_errno(ret);
1569                 goto out;
1570         }
1571
1572         /*
1573          * Check whether the inode can accept inline data.
1574          */
1575         if (oi->ip_clusters != 0 || i_size_read(inode) != 0)
1576                 return 0;
1577
1578         /*
1579          * Check whether the write can fit.
1580          */
1581         di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1582         if (mmap_page ||
1583             end > ocfs2_max_inline_data_with_xattr(inode->i_sb, di))
1584                 return 0;
1585
1586 do_inline_write:
1587         ret = ocfs2_write_begin_inline(mapping, inode, wc);
1588         if (ret) {
1589                 mlog_errno(ret);
1590                 goto out;
1591         }
1592
1593         /*
1594          * This signals to the caller that the data can be written
1595          * inline.
1596          */
1597         written = 1;
1598 out:
1599         return written ? written : ret;
1600 }
1601
1602 /*
1603  * This function only does anything for file systems which can't
1604  * handle sparse files.
1605  *
1606  * What we want to do here is fill in any hole between the current end
1607  * of allocation and the end of our write. That way the rest of the
1608  * write path can treat it as an non-allocating write, which has no
1609  * special case code for sparse/nonsparse files.
1610  */
1611 static int ocfs2_expand_nonsparse_inode(struct inode *inode,
1612                                         struct buffer_head *di_bh,
1613                                         loff_t pos, unsigned len,
1614                                         struct ocfs2_write_ctxt *wc)
1615 {
1616         int ret;
1617         loff_t newsize = pos + len;
1618
1619         BUG_ON(ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)));
1620
1621         if (newsize <= i_size_read(inode))
1622                 return 0;
1623
1624         ret = ocfs2_extend_no_holes(inode, di_bh, newsize, pos);
1625         if (ret)
1626                 mlog_errno(ret);
1627
1628         wc->w_first_new_cpos =
1629                 ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode));
1630
1631         return ret;
1632 }
1633
1634 static int ocfs2_zero_tail(struct inode *inode, struct buffer_head *di_bh,
1635                            loff_t pos)
1636 {
1637         int ret = 0;
1638
1639         BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)));
1640         if (pos > i_size_read(inode))
1641                 ret = ocfs2_zero_extend(inode, di_bh, pos);
1642
1643         return ret;
1644 }
1645
1646 /*
1647  * Try to flush truncate logs if we can free enough clusters from it.
1648  * As for return value, "< 0" means error, "0" no space and "1" means
1649  * we have freed enough spaces and let the caller try to allocate again.
1650  */
1651 static int ocfs2_try_to_free_truncate_log(struct ocfs2_super *osb,
1652                                           unsigned int needed)
1653 {
1654         tid_t target;
1655         int ret = 0;
1656         unsigned int truncated_clusters;
1657
1658         mutex_lock(&osb->osb_tl_inode->i_mutex);
1659         truncated_clusters = osb->truncated_clusters;
1660         mutex_unlock(&osb->osb_tl_inode->i_mutex);
1661
1662         /*
1663          * Check whether we can succeed in allocating if we free
1664          * the truncate log.
1665          */
1666         if (truncated_clusters < needed)
1667                 goto out;
1668
1669         ret = ocfs2_flush_truncate_log(osb);
1670         if (ret) {
1671                 mlog_errno(ret);
1672                 goto out;
1673         }
1674
1675         if (jbd2_journal_start_commit(osb->journal->j_journal, &target)) {
1676                 jbd2_log_wait_commit(osb->journal->j_journal, target);
1677                 ret = 1;
1678         }
1679 out:
1680         return ret;
1681 }
1682
1683 int ocfs2_write_begin_nolock(struct file *filp,
1684                              struct address_space *mapping,
1685                              loff_t pos, unsigned len, unsigned flags,
1686                              struct page **pagep, void **fsdata,
1687                              struct buffer_head *di_bh, struct page *mmap_page)
1688 {
1689         int ret, cluster_of_pages, credits = OCFS2_INODE_UPDATE_CREDITS;
1690         unsigned int clusters_to_alloc, extents_to_split, clusters_need = 0;
1691         struct ocfs2_write_ctxt *wc;
1692         struct inode *inode = mapping->host;
1693         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1694         struct ocfs2_dinode *di;
1695         struct ocfs2_alloc_context *data_ac = NULL;
1696         struct ocfs2_alloc_context *meta_ac = NULL;
1697         handle_t *handle;
1698         struct ocfs2_extent_tree et;
1699         int try_free = 1, ret1;
1700
1701 try_again:
1702         ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
1703         if (ret) {
1704                 mlog_errno(ret);
1705                 return ret;
1706         }
1707
1708         if (ocfs2_supports_inline_data(osb)) {
1709                 ret = ocfs2_try_to_write_inline_data(mapping, inode, pos, len,
1710                                                      mmap_page, wc);
1711                 if (ret == 1) {
1712                         ret = 0;
1713                         goto success;
1714                 }
1715                 if (ret < 0) {
1716                         mlog_errno(ret);
1717                         goto out;
1718                 }
1719         }
1720
1721         if (ocfs2_sparse_alloc(osb))
1722                 ret = ocfs2_zero_tail(inode, di_bh, pos);
1723         else
1724                 ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos, len,
1725                                                    wc);
1726         if (ret) {
1727                 mlog_errno(ret);
1728                 goto out;
1729         }
1730
1731         ret = ocfs2_check_range_for_refcount(inode, pos, len);
1732         if (ret < 0) {
1733                 mlog_errno(ret);
1734                 goto out;
1735         } else if (ret == 1) {
1736                 clusters_need = wc->w_clen;
1737                 ret = ocfs2_refcount_cow(inode, di_bh,
1738                                          wc->w_cpos, wc->w_clen, UINT_MAX);
1739                 if (ret) {
1740                         mlog_errno(ret);
1741                         goto out;
1742                 }
1743         }
1744
1745         ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc,
1746                                         &extents_to_split);
1747         if (ret) {
1748                 mlog_errno(ret);
1749                 goto out;
1750         }
1751         clusters_need += clusters_to_alloc;
1752
1753         di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1754
1755         trace_ocfs2_write_begin_nolock(
1756                         (unsigned long long)OCFS2_I(inode)->ip_blkno,
1757                         (long long)i_size_read(inode),
1758                         le32_to_cpu(di->i_clusters),
1759                         pos, len, flags, mmap_page,
1760                         clusters_to_alloc, extents_to_split);
1761
1762         /*
1763          * We set w_target_from, w_target_to here so that
1764          * ocfs2_write_end() knows which range in the target page to
1765          * write out. An allocation requires that we write the entire
1766          * cluster range.
1767          */
1768         if (clusters_to_alloc || extents_to_split) {
1769                 /*
1770                  * XXX: We are stretching the limits of
1771                  * ocfs2_lock_allocators(). It greatly over-estimates
1772                  * the work to be done.
1773                  */
1774                 ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
1775                                               wc->w_di_bh);
1776                 ret = ocfs2_lock_allocators(inode, &et,
1777                                             clusters_to_alloc, extents_to_split,
1778                                             &data_ac, &meta_ac);
1779                 if (ret) {
1780                         mlog_errno(ret);
1781                         goto out;
1782                 }
1783
1784                 if (data_ac)
1785                         data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
1786
1787                 credits = ocfs2_calc_extend_credits(inode->i_sb,
1788                                                     &di->id2.i_list);
1789
1790         }
1791
1792         /*
1793          * We have to zero sparse allocated clusters, unwritten extent clusters,
1794          * and non-sparse clusters we just extended.  For non-sparse writes,
1795          * we know zeros will only be needed in the first and/or last cluster.
1796          */
1797         if (clusters_to_alloc || extents_to_split ||
1798             (wc->w_clen && (wc->w_desc[0].c_needs_zero ||
1799                             wc->w_desc[wc->w_clen - 1].c_needs_zero)))
1800                 cluster_of_pages = 1;
1801         else
1802                 cluster_of_pages = 0;
1803
1804         ocfs2_set_target_boundaries(osb, wc, pos, len, cluster_of_pages);
1805
1806         handle = ocfs2_start_trans(osb, credits);
1807         if (IS_ERR(handle)) {
1808                 ret = PTR_ERR(handle);
1809                 mlog_errno(ret);
1810                 goto out;
1811         }
1812
1813         wc->w_handle = handle;
1814
1815         if (clusters_to_alloc) {
1816                 ret = dquot_alloc_space_nodirty(inode,
1817                         ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
1818                 if (ret)
1819                         goto out_commit;
1820         }
1821         /*
1822          * We don't want this to fail in ocfs2_write_end(), so do it
1823          * here.
1824          */
1825         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
1826                                       OCFS2_JOURNAL_ACCESS_WRITE);
1827         if (ret) {
1828                 mlog_errno(ret);
1829                 goto out_quota;
1830         }
1831
1832         /*
1833          * Fill our page array first. That way we've grabbed enough so
1834          * that we can zero and flush if we error after adding the
1835          * extent.
1836          */
1837         ret = ocfs2_grab_pages_for_write(mapping, wc, wc->w_cpos, pos, len,
1838                                          cluster_of_pages, mmap_page);
1839         if (ret && ret != -EAGAIN) {
1840                 mlog_errno(ret);
1841                 goto out_quota;
1842         }
1843
1844         /*
1845          * ocfs2_grab_pages_for_write() returns -EAGAIN if it could not lock
1846          * the target page. In this case, we exit with no error and no target
1847          * page. This will trigger the caller, page_mkwrite(), to re-try
1848          * the operation.
1849          */
1850         if (ret == -EAGAIN) {
1851                 BUG_ON(wc->w_target_page);
1852                 ret = 0;
1853                 goto out_quota;
1854         }
1855
1856         ret = ocfs2_write_cluster_by_desc(mapping, data_ac, meta_ac, wc, pos,
1857                                           len);
1858         if (ret) {
1859                 mlog_errno(ret);
1860                 goto out_quota;
1861         }
1862
1863         if (data_ac)
1864                 ocfs2_free_alloc_context(data_ac);
1865         if (meta_ac)
1866                 ocfs2_free_alloc_context(meta_ac);
1867
1868 success:
1869         *pagep = wc->w_target_page;
1870         *fsdata = wc;
1871         return 0;
1872 out_quota:
1873         if (clusters_to_alloc)
1874                 dquot_free_space(inode,
1875                           ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
1876 out_commit:
1877         ocfs2_commit_trans(osb, handle);
1878
1879 out:
1880         ocfs2_free_write_ctxt(wc);
1881
1882         if (data_ac) {
1883                 ocfs2_free_alloc_context(data_ac);
1884                 data_ac = NULL;
1885         }
1886         if (meta_ac) {
1887                 ocfs2_free_alloc_context(meta_ac);
1888                 meta_ac = NULL;
1889         }
1890
1891         if (ret == -ENOSPC && try_free) {
1892                 /*
1893                  * Try to free some truncate log so that we can have enough
1894                  * clusters to allocate.
1895                  */
1896                 try_free = 0;
1897
1898                 ret1 = ocfs2_try_to_free_truncate_log(osb, clusters_need);
1899                 if (ret1 == 1)
1900                         goto try_again;
1901
1902                 if (ret1 < 0)
1903                         mlog_errno(ret1);
1904         }
1905
1906         return ret;
1907 }
1908
1909 static int ocfs2_write_begin(struct file *file, struct address_space *mapping,
1910                              loff_t pos, unsigned len, unsigned flags,
1911                              struct page **pagep, void **fsdata)
1912 {
1913         int ret;
1914         struct buffer_head *di_bh = NULL;
1915         struct inode *inode = mapping->host;
1916
1917         ret = ocfs2_inode_lock(inode, &di_bh, 1);
1918         if (ret) {
1919                 mlog_errno(ret);
1920                 return ret;
1921         }
1922
1923         /*
1924          * Take alloc sem here to prevent concurrent lookups. That way
1925          * the mapping, zeroing and tree manipulation within
1926          * ocfs2_write() will be safe against ->readpage(). This
1927          * should also serve to lock out allocation from a shared
1928          * writeable region.
1929          */
1930         down_write(&OCFS2_I(inode)->ip_alloc_sem);
1931
1932         ret = ocfs2_write_begin_nolock(file, mapping, pos, len, flags, pagep,
1933                                        fsdata, di_bh, NULL);
1934         if (ret) {
1935                 mlog_errno(ret);
1936                 goto out_fail;
1937         }
1938
1939         brelse(di_bh);
1940
1941         return 0;
1942
1943 out_fail:
1944         up_write(&OCFS2_I(inode)->ip_alloc_sem);
1945
1946         brelse(di_bh);
1947         ocfs2_inode_unlock(inode, 1);
1948
1949         return ret;
1950 }
1951
1952 static void ocfs2_write_end_inline(struct inode *inode, loff_t pos,
1953                                    unsigned len, unsigned *copied,
1954                                    struct ocfs2_dinode *di,
1955                                    struct ocfs2_write_ctxt *wc)
1956 {
1957         void *kaddr;
1958
1959         if (unlikely(*copied < len)) {
1960                 if (!PageUptodate(wc->w_target_page)) {
1961                         *copied = 0;
1962                         return;
1963                 }
1964         }
1965
1966         kaddr = kmap_atomic(wc->w_target_page);
1967         memcpy(di->id2.i_data.id_data + pos, kaddr + pos, *copied);
1968         kunmap_atomic(kaddr);
1969
1970         trace_ocfs2_write_end_inline(
1971              (unsigned long long)OCFS2_I(inode)->ip_blkno,
1972              (unsigned long long)pos, *copied,
1973              le16_to_cpu(di->id2.i_data.id_count),
1974              le16_to_cpu(di->i_dyn_features));
1975 }
1976
1977 int ocfs2_write_end_nolock(struct address_space *mapping,
1978                            loff_t pos, unsigned len, unsigned copied,
1979                            struct page *page, void *fsdata)
1980 {
1981         int i;
1982         unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1);
1983         struct inode *inode = mapping->host;
1984         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1985         struct ocfs2_write_ctxt *wc = fsdata;
1986         struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1987         handle_t *handle = wc->w_handle;
1988         struct page *tmppage;
1989
1990         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1991                 ocfs2_write_end_inline(inode, pos, len, &copied, di, wc);
1992                 goto out_write_size;
1993         }
1994
1995         if (unlikely(copied < len)) {
1996                 if (!PageUptodate(wc->w_target_page))
1997                         copied = 0;
1998
1999                 ocfs2_zero_new_buffers(wc->w_target_page, start+copied,
2000                                        start+len);
2001         }
2002         flush_dcache_page(wc->w_target_page);
2003
2004         for(i = 0; i < wc->w_num_pages; i++) {
2005                 tmppage = wc->w_pages[i];
2006
2007                 if (tmppage == wc->w_target_page) {
2008                         from = wc->w_target_from;
2009                         to = wc->w_target_to;
2010
2011                         BUG_ON(from > PAGE_CACHE_SIZE ||
2012                                to > PAGE_CACHE_SIZE ||
2013                                to < from);
2014                 } else {
2015                         /*
2016                          * Pages adjacent to the target (if any) imply
2017                          * a hole-filling write in which case we want
2018                          * to flush their entire range.
2019                          */
2020                         from = 0;
2021                         to = PAGE_CACHE_SIZE;
2022                 }
2023
2024                 if (page_has_buffers(tmppage)) {
2025                         if (ocfs2_should_order_data(inode))
2026                                 ocfs2_jbd2_file_inode(wc->w_handle, inode);
2027                         block_commit_write(tmppage, from, to);
2028                 }
2029         }
2030
2031 out_write_size:
2032         pos += copied;
2033         if (pos > i_size_read(inode)) {
2034                 i_size_write(inode, pos);
2035                 mark_inode_dirty(inode);
2036         }
2037         inode->i_blocks = ocfs2_inode_sector_count(inode);
2038         di->i_size = cpu_to_le64((u64)i_size_read(inode));
2039         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2040         di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec);
2041         di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
2042         ocfs2_update_inode_fsync_trans(handle, inode, 1);
2043         ocfs2_journal_dirty(handle, wc->w_di_bh);
2044
2045         ocfs2_commit_trans(osb, handle);
2046
2047         ocfs2_run_deallocs(osb, &wc->w_dealloc);
2048
2049         ocfs2_free_write_ctxt(wc);
2050
2051         return copied;
2052 }
2053
2054 static int ocfs2_write_end(struct file *file, struct address_space *mapping,
2055                            loff_t pos, unsigned len, unsigned copied,
2056                            struct page *page, void *fsdata)
2057 {
2058         int ret;
2059         struct inode *inode = mapping->host;
2060
2061         ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);
2062
2063         up_write(&OCFS2_I(inode)->ip_alloc_sem);
2064         ocfs2_inode_unlock(inode, 1);
2065
2066         return ret;
2067 }
2068
2069 const struct address_space_operations ocfs2_aops = {
2070         .readpage               = ocfs2_readpage,
2071         .readpages              = ocfs2_readpages,
2072         .writepage              = ocfs2_writepage,
2073         .write_begin            = ocfs2_write_begin,
2074         .write_end              = ocfs2_write_end,
2075         .bmap                   = ocfs2_bmap,
2076         .direct_IO              = ocfs2_direct_IO,
2077         .invalidatepage         = block_invalidatepage,
2078         .releasepage            = ocfs2_releasepage,
2079         .migratepage            = buffer_migrate_page,
2080         .is_partially_uptodate  = block_is_partially_uptodate,
2081         .error_remove_page      = generic_error_remove_page,
2082 };