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                 mlog(ML_ERROR, "block offset is outside the allocated size: "
  84                      "%llu\n", (unsigned long long)iblock);
  85                 goto bail;
  86         }
  87
  88         /* We don't use the page cache to create symlink data, so if
  89          * need be, copy it over from the buffer cache. */
  90         if (!buffer_uptodate(bh_result) && ocfs2_inode_is_new(inode)) {
  91                 u64 blkno = le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) +
  92                             iblock;
  93                 buffer_cache_bh = sb_getblk(osb->sb, blkno);
  94                 if (!buffer_cache_bh) {
  95                         mlog(ML_ERROR, "couldn't getblock for symlink!\n");
  96                         goto bail;
  97                 }
  98
  99                 /* we haven't locked out transactions, so a commit
 100                  * could've happened. Since we've got a reference on
 101                  * the bh, even if it commits while we're doing the
 102                  * copy, the data is still good. */
 103                 if (buffer_jbd(buffer_cache_bh)
 104                     && ocfs2_inode_is_new(inode)) {
 105                         kaddr = kmap_atomic(bh_result->b_page);
 106                         if (!kaddr) {
 107                                 mlog(ML_ERROR, "couldn't kmap!\n");
 108                                 goto bail;
 109                         }
 110                         memcpy(kaddr + (bh_result->b_size * iblock),
 111                                buffer_cache_bh->b_data,
 112                                bh_result->b_size);
 113                         kunmap_atomic(kaddr);
 114                         set_buffer_uptodate(bh_result);
 115                 }
 116                 brelse(buffer_cache_bh);
 117         }
 118
 119         map_bh(bh_result, inode->i_sb,
 120                le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + iblock);
 121
 122         err = 0;
 123
 124 bail:
 125         brelse(bh);
 126
 127         return err;
 128 }
 129
 130 int ocfs2_get_block(struct inode *inode, sector_t iblock,
 131                     struct buffer_head *bh_result, int create)
 132 {
 133         int err = 0;
 134         unsigned int ext_flags;
 135         u64 max_blocks = bh_result->b_size >> inode->i_blkbits;
 136         u64 p_blkno, count, past_eof;
 137         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 138
 139         trace_ocfs2_get_block((unsigned long long)OCFS2_I(inode)->ip_blkno,
 140                               (unsigned long long)iblock, bh_result, create);
 141
 142         if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
 143                 mlog(ML_NOTICE, "get_block on system inode 0x%p (%lu)\n",
 144                      inode, inode->i_ino);
 145
 146         if (S_ISLNK(inode->i_mode)) {
 147                 /* this always does I/O for some reason. */
 148                 err = ocfs2_symlink_get_block(inode, iblock, bh_result, create);
 149                 goto bail;
 150         }
 151
 152         err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, &count,
 153                                           &ext_flags);
 154         if (err) {
 155                 mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, "
 156                      "%llu, NULL)\n", err, inode, (unsigned long long)iblock,
 157                      (unsigned long long)p_blkno);
 158                 goto bail;
 159         }
 160
 161         if (max_blocks < count)
 162                 count = max_blocks;
 163
 164         /*
 165          * ocfs2 never allocates in this function - the only time we
 166          * need to use BH_New is when we're extending i_size on a file
 167          * system which doesn't support holes, in which case BH_New
 168          * allows __block_write_begin() to zero.
 169          *
 170          * If we see this on a sparse file system, then a truncate has
 171          * raced us and removed the cluster. In this case, we clear
 172          * the buffers dirty and uptodate bits and let the buffer code
 173          * ignore it as a hole.
 174          */
 175         if (create && p_blkno == 0 && ocfs2_sparse_alloc(osb)) {
 176                 clear_buffer_dirty(bh_result);
 177                 clear_buffer_uptodate(bh_result);
 178                 goto bail;
 179         }
 180
 181         /* Treat the unwritten extent as a hole for zeroing purposes. */
 182         if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
 183                 map_bh(bh_result, inode->i_sb, p_blkno);
 184
 185         bh_result->b_size = count << inode->i_blkbits;
 186
 187         if (!ocfs2_sparse_alloc(osb)) {
 188                 if (p_blkno == 0) {
 189                         err = -EIO;
 190                         mlog(ML_ERROR,
 191                              "iblock = %llu p_blkno = %llu blkno=(%llu)\n",
 192                              (unsigned long long)iblock,
 193                              (unsigned long long)p_blkno,
 194                              (unsigned long long)OCFS2_I(inode)->ip_blkno);
 195                         mlog(ML_ERROR, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode), OCFS2_I(inode)->ip_clusters);
 196                         dump_stack();
 197                         goto bail;
 198                 }
 199         }
 200
 201         past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
 202
 203         trace_ocfs2_get_block_end((unsigned long long)OCFS2_I(inode)->ip_blkno,
 204                                   (unsigned long long)past_eof);
 205         if (create && (iblock >= past_eof))
 206                 set_buffer_new(bh_result);
 207
 208 bail:
 209         if (err < 0)
 210                 err = -EIO;
 211
 212         return err;
 213 }
 214
 215 int ocfs2_read_inline_data(struct inode *inode, struct page *page,
 216                            struct buffer_head *di_bh)
 217 {
 218         void *kaddr;
 219         loff_t size;
 220         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 221
 222         if (!(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)) {
 223                 ocfs2_error(inode->i_sb, "Inode %llu lost inline data flag",
 224                             (unsigned long long)OCFS2_I(inode)->ip_blkno);
 225                 return -EROFS;
 226         }
 227
 228         size = i_size_read(inode);
 229
 230         if (size > PAGE_CACHE_SIZE ||
 231             size > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) {
 232                 ocfs2_error(inode->i_sb,
 233                             "Inode %llu has with inline data has bad size: %Lu",
 234                             (unsigned long long)OCFS2_I(inode)->ip_blkno,
 235                             (unsigned long long)size);
 236                 return -EROFS;
 237         }
 238
 239         kaddr = kmap_atomic(page);
 240         if (size)
 241                 memcpy(kaddr, di->id2.i_data.id_data, size);
 242         /* Clear the remaining part of the page */
 243         memset(kaddr + size, 0, PAGE_CACHE_SIZE - size);
 244         flush_dcache_page(page);
 245         kunmap_atomic(kaddr);
 246
 247         SetPageUptodate(page);
 248
 249         return 0;
 250 }
 251
 252 static int ocfs2_readpage_inline(struct inode *inode, struct page *page)
 253 {
 254         int ret;
 255         struct buffer_head *di_bh = NULL;
 256
 257         BUG_ON(!PageLocked(page));
 258         BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL));
 259
 260         ret = ocfs2_read_inode_block(inode, &di_bh);
 261         if (ret) {
 262                 mlog_errno(ret);
 263                 goto out;
 264         }
 265
 266         ret = ocfs2_read_inline_data(inode, page, di_bh);
 267 out:
 268         unlock_page(page);
 269
 270         brelse(di_bh);
 271         return ret;
 272 }
 273
 274 static int ocfs2_readpage(struct file *file, struct page *page)
 275 {
 276         struct inode *inode = page->mapping->host;
 277         struct ocfs2_inode_info *oi = OCFS2_I(inode);
 278         loff_t start = (loff_t)page->index << PAGE_CACHE_SHIFT;
 279         int ret, unlock = 1;
 280
 281         trace_ocfs2_readpage((unsigned long long)oi->ip_blkno,
 282                              (page ? page->index : 0));
 283
 284         ret = ocfs2_inode_lock_with_page(inode, NULL, 0, page);
 285         if (ret != 0) {
 286                 if (ret == AOP_TRUNCATED_PAGE)
 287                         unlock = 0;
 288                 mlog_errno(ret);
 289                 goto out;
 290         }
 291
 292         if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
 293                 /*
 294                  * Unlock the page and cycle ip_alloc_sem so that we don't
 295                  * busyloop waiting for ip_alloc_sem to unlock
 296                  */
 297                 ret = AOP_TRUNCATED_PAGE;
 298                 unlock_page(page);
 299                 unlock = 0;
 300                 down_read(&oi->ip_alloc_sem);
 301                 up_read(&oi->ip_alloc_sem);
 302                 goto out_inode_unlock;
 303         }
 304
 305         /*
 306          * i_size might have just been updated as we grabed the meta lock.  We
 307          * might now be discovering a truncate that hit on another node.
 308          * block_read_full_page->get_block freaks out if it is asked to read
 309          * beyond the end of a file, so we check here.  Callers
 310          * (generic_file_read, vm_ops->fault) are clever enough to check i_size
 311          * and notice that the page they just read isn't needed.
 312          *
 313          * XXX sys_readahead() seems to get that wrong?
 314          */
 315         if (start >= i_size_read(inode)) {
 316                 zero_user(page, 0, PAGE_SIZE);
 317                 SetPageUptodate(page);
 318                 ret = 0;
 319                 goto out_alloc;
 320         }
 321
 322         if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 323                 ret = ocfs2_readpage_inline(inode, page);
 324         else
 325                 ret = block_read_full_page(page, ocfs2_get_block);
 326         unlock = 0;
 327
 328 out_alloc:
 329         up_read(&OCFS2_I(inode)->ip_alloc_sem);
 330 out_inode_unlock:
 331         ocfs2_inode_unlock(inode, 0);
 332 out:
 333         if (unlock)
 334                 unlock_page(page);
 335         return ret;
 336 }
 337
 338 /*
 339  * This is used only for read-ahead. Failures or difficult to handle
 340  * situations are safe to ignore.
 341  *
 342  * Right now, we don't bother with BH_Boundary - in-inode extent lists
 343  * are quite large (243 extents on 4k blocks), so most inodes don't
 344  * grow out to a tree. If need be, detecting boundary extents could
 345  * trivially be added in a future version of ocfs2_get_block().
 346  */
 347 static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
 348                            struct list_head *pages, unsigned nr_pages)
 349 {
 350         int ret, err = -EIO;
 351         struct inode *inode = mapping->host;
 352         struct ocfs2_inode_info *oi = OCFS2_I(inode);
 353         loff_t start;
 354         struct page *last;
 355
 356         /*
 357          * Use the nonblocking flag for the dlm code to avoid page
 358          * lock inversion, but don't bother with retrying.
 359          */
 360         ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK);
 361         if (ret)
 362                 return err;
 363
 364         if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
 365                 ocfs2_inode_unlock(inode, 0);
 366                 return err;
 367         }
 368
 369         /*
 370          * Don't bother with inline-data. There isn't anything
 371          * to read-ahead in that case anyway...
 372          */
 373         if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 374                 goto out_unlock;
 375
 376         /*
 377          * Check whether a remote node truncated this file - we just
 378          * drop out in that case as it's not worth handling here.
 379          */
 380         last = list_entry(pages->prev, struct page, lru);
 381         start = (loff_t)last->index << PAGE_CACHE_SHIFT;
 382         if (start >= i_size_read(inode))
 383                 goto out_unlock;
 384
 385         err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block);
 386
 387 out_unlock:
 388         up_read(&oi->ip_alloc_sem);
 389         ocfs2_inode_unlock(inode, 0);
 390
 391         return err;
 392 }
 393
 394 /* Note: Because we don't support holes, our allocation has
 395  * already happened (allocation writes zeros to the file data)
 396  * so we don't have to worry about ordered writes in
 397  * ocfs2_writepage.
 398  *
 399  * ->writepage is called during the process of invalidating the page cache
 400  * during blocked lock processing.  It can't block on any cluster locks
 401  * to during block mapping.  It's relying on the fact that the block
 402  * mapping can't have disappeared under the dirty pages that it is
 403  * being asked to write back.
 404  */
 405 static int ocfs2_writepage(struct page *page, struct writeback_control *wbc)
 406 {
 407         trace_ocfs2_writepage(
 408                 (unsigned long long)OCFS2_I(page->mapping->host)->ip_blkno,
 409                 page->index);
 410
 411         return block_write_full_page(page, ocfs2_get_block, wbc);
 412 }
 413
 414 /* Taken from ext3. We don't necessarily need the full blown
 415  * functionality yet, but IMHO it's better to cut and paste the whole
 416  * thing so we can avoid introducing our own bugs (and easily pick up
 417  * their fixes when they happen) --Mark */
 418 int walk_page_buffers(  handle_t *handle,
 419                         struct buffer_head *head,
 420                         unsigned from,
 421                         unsigned to,
 422                         int *partial,
 423                         int (*fn)(      handle_t *handle,
 424                                         struct buffer_head *bh))
 425 {
 426         struct buffer_head *bh;
 427         unsigned block_start, block_end;
 428         unsigned blocksize = head->b_size;
 429         int err, ret = 0;
 430         struct buffer_head *next;
 431
 432         for (   bh = head, block_start = 0;
 433                 ret == 0 && (bh != head || !block_start);
 434                 block_start = block_end, bh = next)
 435         {
 436                 next = bh->b_this_page;
 437                 block_end = block_start + blocksize;
 438                 if (block_end <= from || block_start >= to) {
 439                         if (partial && !buffer_uptodate(bh))
 440                                 *partial = 1;
 441                         continue;
 442                 }
 443                 err = (*fn)(handle, bh);
 444                 if (!ret)
 445                         ret = err;
 446         }
 447         return ret;
 448 }
 449
 450 static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
 451 {
 452         sector_t status;
 453         u64 p_blkno = 0;
 454         int err = 0;
 455         struct inode *inode = mapping->host;
 456
 457         trace_ocfs2_bmap((unsigned long long)OCFS2_I(inode)->ip_blkno,
 458                          (unsigned long long)block);
 459
 460         /* We don't need to lock journal system files, since they aren't
 461          * accessed concurrently from multiple nodes.
 462          */
 463         if (!INODE_JOURNAL(inode)) {
 464                 err = ocfs2_inode_lock(inode, NULL, 0);
 465                 if (err) {
 466                         if (err != -ENOENT)
 467                                 mlog_errno(err);
 468                         goto bail;
 469                 }
 470                 down_read(&OCFS2_I(inode)->ip_alloc_sem);
 471         }
 472
 473         if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
 474                 err = ocfs2_extent_map_get_blocks(inode, block, &p_blkno, NULL,
 475                                                   NULL);
 476
 477         if (!INODE_JOURNAL(inode)) {
 478                 up_read(&OCFS2_I(inode)->ip_alloc_sem);
 479                 ocfs2_inode_unlock(inode, 0);
 480         }
 481
 482         if (err) {
 483                 mlog(ML_ERROR, "get_blocks() failed, block = %llu\n",
 484                      (unsigned long long)block);
 485                 mlog_errno(err);
 486                 goto bail;
 487         }
 488
 489 bail:
 490         status = err ? 0 : p_blkno;
 491
 492         return status;
 493 }
 494
 495 /*
 496  * TODO: Make this into a generic get_blocks function.
 497  *
 498  * From do_direct_io in direct-io.c:
 499  *  "So what we do is to permit the ->get_blocks function to populate
 500  *   bh.b_size with the size of IO which is permitted at this offset and
 501  *   this i_blkbits."
 502  *
 503  * This function is called directly from get_more_blocks in direct-io.c.
 504  *
 505  * called like this: dio->get_blocks(dio->inode, fs_startblk,
 506  *                                      fs_count, map_bh, dio->rw == WRITE);
 507  *
 508  * Note that we never bother to allocate blocks here, and thus ignore the
 509  * create argument.
 510  */
 511 static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
 512                                      struct buffer_head *bh_result, int create)
 513 {
 514         int ret;
 515         u64 p_blkno, inode_blocks, contig_blocks;
 516         unsigned int ext_flags;
 517         unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
 518         unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
 519
 520         /* This function won't even be called if the request isn't all
 521          * nicely aligned and of the right size, so there's no need
 522          * for us to check any of that. */
 523
 524         inode_blocks = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
 525
 526         /* This figures out the size of the next contiguous block, and
 527          * our logical offset */
 528         ret = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno,
 529                                           &contig_blocks, &ext_flags);
 530         if (ret) {
 531                 mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n",
 532                      (unsigned long long)iblock);
 533                 ret = -EIO;
 534                 goto bail;
 535         }
 536
 537         /* We should already CoW the refcounted extent in case of create. */
 538         BUG_ON(create && (ext_flags & OCFS2_EXT_REFCOUNTED));
 539
 540         /*
 541          * get_more_blocks() expects us to describe a hole by clearing
 542          * the mapped bit on bh_result().
 543          *
 544          * Consider an unwritten extent as a hole.
 545          */
 546         if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
 547                 map_bh(bh_result, inode->i_sb, p_blkno);
 548         else
 549                 clear_buffer_mapped(bh_result);
 550
 551         /* make sure we don't map more than max_blocks blocks here as
 552            that's all the kernel will handle at this point. */
 553         if (max_blocks < contig_blocks)
 554                 contig_blocks = max_blocks;
 555         bh_result->b_size = contig_blocks << blocksize_bits;
 556 bail:
 557         return ret;
 558 }
 559
 560 /*
 561  * ocfs2_dio_end_io is called by the dio core when a dio is finished.  We're
 562  * particularly interested in the aio/dio case.  We use the rw_lock DLM lock
 563  * to protect io on one node from truncation on another.
 564  */
 565 static void ocfs2_dio_end_io(struct kiocb *iocb,
 566                              loff_t offset,
 567                              ssize_t bytes,
 568                              void *private,
 569                              int ret,
 570                              bool is_async)
 571 {
 572         struct inode *inode = file_inode(iocb->ki_filp);
 573         int level;
 574         wait_queue_head_t *wq = ocfs2_ioend_wq(inode);
 575
 576         /* this io's submitter should not have unlocked this before we could */
 577         BUG_ON(!ocfs2_iocb_is_rw_locked(iocb));
 578
 579         if (ocfs2_iocb_is_sem_locked(iocb))
 580                 ocfs2_iocb_clear_sem_locked(iocb);
 581
 582         if (ocfs2_iocb_is_unaligned_aio(iocb)) {
 583                 ocfs2_iocb_clear_unaligned_aio(iocb);
 584
 585                 if (atomic_dec_and_test(&OCFS2_I(inode)->ip_unaligned_aio) &&
 586                     waitqueue_active(wq)) {
 587                         wake_up_all(wq);
 588                 }
 589         }
 590
 591         ocfs2_iocb_clear_rw_locked(iocb);
 592
 593         level = ocfs2_iocb_rw_locked_level(iocb);
 594         ocfs2_rw_unlock(inode, level);
 595
 596         inode_dio_done(inode);
 597         if (is_async)
 598                 aio_complete(iocb, ret, 0);
 599 }
 600
 601 /*
 602  * ocfs2_invalidatepage() and ocfs2_releasepage() are shamelessly stolen
 603  * from ext3.  PageChecked() bits have been removed as OCFS2 does not
 604  * do journalled data.
 605  */
 606 static void ocfs2_invalidatepage(struct page *page, unsigned long offset)
 607 {
 608         journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal;
 609
 610         jbd2_journal_invalidatepage(journal, page, offset);
 611 }
 612
 613 static int ocfs2_releasepage(struct page *page, gfp_t wait)
 614 {
 615         journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal;
 616
 617         if (!page_has_buffers(page))
 618                 return 0;
 619         return jbd2_journal_try_to_free_buffers(journal, page, wait);
 620 }
 621
 622 static ssize_t ocfs2_direct_IO(int rw,
 623                                struct kiocb *iocb,
 624                                const struct iovec *iov,
 625                                loff_t offset,
 626                                unsigned long nr_segs)
 627 {
 628         struct file *file = iocb->ki_filp;
 629         struct inode *inode = file_inode(file)->i_mapping->host;
 630
 631         /*
 632          * Fallback to buffered I/O if we see an inode without
 633          * extents.
 634          */
 635         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 636                 return 0;
 637
 638         /* Fallback to buffered I/O if we are appending. */
 639         if (i_size_read(inode) <= offset)
 640                 return 0;
 641
 642         return __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev,
 643                                     iov, offset, nr_segs,
 644                                     ocfs2_direct_IO_get_blocks,
 645                                     ocfs2_dio_end_io, NULL, 0);
 646 }
 647
 648 static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
 649                                             u32 cpos,
 650                                             unsigned int *start,
 651                                             unsigned int *end)
 652 {
 653         unsigned int cluster_start = 0, cluster_end = PAGE_CACHE_SIZE;
 654
 655         if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) {
 656                 unsigned int cpp;
 657
 658                 cpp = 1 << (PAGE_CACHE_SHIFT - osb->s_clustersize_bits);
 659
 660                 cluster_start = cpos % cpp;
 661                 cluster_start = cluster_start << osb->s_clustersize_bits;
 662
 663                 cluster_end = cluster_start + osb->s_clustersize;
 664         }
 665
 666         BUG_ON(cluster_start > PAGE_SIZE);
 667         BUG_ON(cluster_end > PAGE_SIZE);
 668
 669         if (start)
 670                 *start = cluster_start;
 671         if (end)
 672                 *end = cluster_end;
 673 }
 674
 675 /*
 676  * 'from' and 'to' are the region in the page to avoid zeroing.
 677  *
 678  * If pagesize > clustersize, this function will avoid zeroing outside
 679  * of the cluster boundary.
 680  *
 681  * from == to == 0 is code for "zero the entire cluster region"
 682  */
 683 static void ocfs2_clear_page_regions(struct page *page,
 684                                      struct ocfs2_super *osb, u32 cpos,
 685                                      unsigned from, unsigned to)
 686 {
 687         void *kaddr;
 688         unsigned int cluster_start, cluster_end;
 689
 690         ocfs2_figure_cluster_boundaries(osb, cpos, &cluster_start, &cluster_end);
 691
 692         kaddr = kmap_atomic(page);
 693
 694         if (from || to) {
 695                 if (from > cluster_start)
 696                         memset(kaddr + cluster_start, 0, from - cluster_start);
 697                 if (to < cluster_end)
 698                         memset(kaddr + to, 0, cluster_end - to);
 699         } else {
 700                 memset(kaddr + cluster_start, 0, cluster_end - cluster_start);
 701         }
 702
 703         kunmap_atomic(kaddr);
 704 }
 705
 706 /*
 707  * Nonsparse file systems fully allocate before we get to the write
 708  * code. This prevents ocfs2_write() from tagging the write as an
 709  * allocating one, which means ocfs2_map_page_blocks() might try to
 710  * read-in the blocks at the tail of our file. Avoid reading them by
 711  * testing i_size against each block offset.
 712  */
 713 static int ocfs2_should_read_blk(struct inode *inode, struct page *page,
 714                                  unsigned int block_start)
 715 {
 716         u64 offset = page_offset(page) + block_start;
 717
 718         if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
 719                 return 1;
 720
 721         if (i_size_read(inode) > offset)
 722                 return 1;
 723
 724         return 0;
 725 }
 726
 727 /*
 728  * Some of this taken from __block_write_begin(). We already have our
 729  * mapping by now though, and the entire write will be allocating or
 730  * it won't, so not much need to use BH_New.
 731  *
 732  * This will also skip zeroing, which is handled externally.
 733  */
 734 int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
 735                           struct inode *inode, unsigned int from,
 736                           unsigned int to, int new)
 737 {
 738         int ret = 0;
 739         struct buffer_head *head, *bh, *wait[2], **wait_bh = wait;
 740         unsigned int block_end, block_start;
 741         unsigned int bsize = 1 << inode->i_blkbits;
 742
 743         if (!page_has_buffers(page))
 744                 create_empty_buffers(page, bsize, 0);
 745
 746         head = page_buffers(page);
 747         for (bh = head, block_start = 0; bh != head || !block_start;
 748              bh = bh->b_this_page, block_start += bsize) {
 749                 block_end = block_start + bsize;
 750
 751                 clear_buffer_new(bh);
 752
 753                 /*
 754                  * Ignore blocks outside of our i/o range -
 755                  * they may belong to unallocated clusters.
 756                  */
 757                 if (block_start >= to || block_end <= from) {
 758                         if (PageUptodate(page))
 759                                 set_buffer_uptodate(bh);
 760                         continue;
 761                 }
 762
 763                 /*
 764                  * For an allocating write with cluster size >= page
 765                  * size, we always write the entire page.
 766                  */
 767                 if (new)
 768                         set_buffer_new(bh);
 769
 770                 if (!buffer_mapped(bh)) {
 771                         map_bh(bh, inode->i_sb, *p_blkno);
 772                         unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
 773                 }
 774
 775                 if (PageUptodate(page)) {
 776                         if (!buffer_uptodate(bh))
 777                                 set_buffer_uptodate(bh);
 778                 } else if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
 779                            !buffer_new(bh) &&
 780                            ocfs2_should_read_blk(inode, page, block_start) &&
 781                            (block_start < from || block_end > to)) {
 782                         ll_rw_block(READ, 1, &bh);
 783                         *wait_bh++=bh;
 784                 }
 785
 786                 *p_blkno = *p_blkno + 1;
 787         }
 788
 789         /*
 790          * If we issued read requests - let them complete.
 791          */
 792         while(wait_bh > wait) {
 793                 wait_on_buffer(*--wait_bh);
 794                 if (!buffer_uptodate(*wait_bh))
 795                         ret = -EIO;
 796         }
 797
 798         if (ret == 0 || !new)
 799                 return ret;
 800
 801         /*
 802          * If we get -EIO above, zero out any newly allocated blocks
 803          * to avoid exposing stale data.
 804          */
 805         bh = head;
 806         block_start = 0;
 807         do {
 808                 block_end = block_start + bsize;
 809                 if (block_end <= from)
 810                         goto next_bh;
 811                 if (block_start >= to)
 812                         break;
 813
 814                 zero_user(page, block_start, bh->b_size);
 815                 set_buffer_uptodate(bh);
 816                 mark_buffer_dirty(bh);
 817
 818 next_bh:
 819                 block_start = block_end;
 820                 bh = bh->b_this_page;
 821         } while (bh != head);
 822
 823         return ret;
 824 }
 825
 826 #if (PAGE_CACHE_SIZE >= OCFS2_MAX_CLUSTERSIZE)
 827 #define OCFS2_MAX_CTXT_PAGES    1
 828 #else
 829 #define OCFS2_MAX_CTXT_PAGES    (OCFS2_MAX_CLUSTERSIZE / PAGE_CACHE_SIZE)
 830 #endif
 831
 832 #define OCFS2_MAX_CLUSTERS_PER_PAGE     (PAGE_CACHE_SIZE / OCFS2_MIN_CLUSTERSIZE)
 833
 834 /*
 835  * Describe the state of a single cluster to be written to.
 836  */
 837 struct ocfs2_write_cluster_desc {
 838         u32             c_cpos;
 839         u32             c_phys;
 840         /*
 841          * Give this a unique field because c_phys eventually gets
 842          * filled.
 843          */
 844         unsigned        c_new;
 845         unsigned        c_unwritten;
 846         unsigned        c_needs_zero;
 847 };
 848
 849 struct ocfs2_write_ctxt {
 850         /* Logical cluster position / len of write */
 851         u32                             w_cpos;
 852         u32                             w_clen;
 853
 854         /* First cluster allocated in a nonsparse extend */
 855         u32                             w_first_new_cpos;
 856
 857         struct ocfs2_write_cluster_desc w_desc[OCFS2_MAX_CLUSTERS_PER_PAGE];
 858
 859         /*
 860          * This is true if page_size > cluster_size.
 861          *
 862          * It triggers a set of special cases during write which might
 863          * have to deal with allocating writes to partial pages.
 864          */
 865         unsigned int                    w_large_pages;
 866
 867         /*
 868          * Pages involved in this write.
 869          *
 870          * w_target_page is the page being written to by the user.
 871          *
 872          * w_pages is an array of pages which always contains
 873          * w_target_page, and in the case of an allocating write with
 874          * page_size < cluster size, it will contain zero'd and mapped
 875          * pages adjacent to w_target_page which need to be written
 876          * out in so that future reads from that region will get
 877          * zero's.
 878          */
 879         unsigned int                    w_num_pages;
 880         struct page                     *w_pages[OCFS2_MAX_CTXT_PAGES];
 881         struct page                     *w_target_page;
 882
 883         /*
 884          * w_target_locked is used for page_mkwrite path indicating no unlocking
 885          * against w_target_page in ocfs2_write_end_nolock.
 886          */
 887         unsigned int                    w_target_locked:1;
 888
 889         /*
 890          * ocfs2_write_end() uses this to know what the real range to
 891          * write in the target should be.
 892          */
 893         unsigned int                    w_target_from;
 894         unsigned int                    w_target_to;
 895
 896         /*
 897          * We could use journal_current_handle() but this is cleaner,
 898          * IMHO -Mark
 899          */
 900         handle_t                        *w_handle;
 901
 902         struct buffer_head              *w_di_bh;
 903
 904         struct ocfs2_cached_dealloc_ctxt w_dealloc;
 905 };
 906
 907 void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
 908 {
 909         int i;
 910
 911         for(i = 0; i < num_pages; i++) {
 912                 if (pages[i]) {
 913                         unlock_page(pages[i]);
 914                         mark_page_accessed(pages[i]);
 915                         page_cache_release(pages[i]);
 916                 }
 917         }
 918 }
 919
 920 static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
 921 {
 922         int i;
 923
 924         /*
 925          * w_target_locked is only set to true in the page_mkwrite() case.
 926          * The intent is to allow us to lock the target page from write_begin()
 927          * to write_end(). The caller must hold a ref on w_target_page.
 928          */
 929         if (wc->w_target_locked) {
 930                 BUG_ON(!wc->w_target_page);
 931                 for (i = 0; i < wc->w_num_pages; i++) {
 932                         if (wc->w_target_page == wc->w_pages[i]) {
 933                                 wc->w_pages[i] = NULL;
 934                                 break;
 935                         }
 936                 }
 937                 mark_page_accessed(wc->w_target_page);
 938                 page_cache_release(wc->w_target_page);
 939         }
 940         ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
 941
 942         brelse(wc->w_di_bh);
 943         kfree(wc);
 944 }
 945
 946 static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
 947                                   struct ocfs2_super *osb, loff_t pos,
 948                                   unsigned len, struct buffer_head *di_bh)
 949 {
 950         u32 cend;
 951         struct ocfs2_write_ctxt *wc;
 952
 953         wc = kzalloc(sizeof(struct ocfs2_write_ctxt), GFP_NOFS);
 954         if (!wc)
 955                 return -ENOMEM;
 956
 957         wc->w_cpos = pos >> osb->s_clustersize_bits;
 958         wc->w_first_new_cpos = UINT_MAX;
 959         cend = (pos + len - 1) >> osb->s_clustersize_bits;
 960         wc->w_clen = cend - wc->w_cpos + 1;
 961         get_bh(di_bh);
 962         wc->w_di_bh = di_bh;
 963
 964         if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))
 965                 wc->w_large_pages = 1;
 966         else
 967                 wc->w_large_pages = 0;
 968
 969         ocfs2_init_dealloc_ctxt(&wc->w_dealloc);
 970
 971         *wcp = wc;
 972
 973         return 0;
 974 }
 975
 976 /*
 977  * If a page has any new buffers, zero them out here, and mark them uptodate
 978  * and dirty so they'll be written out (in order to prevent uninitialised
 979  * block data from leaking). And clear the new bit.
 980  */
 981 static void ocfs2_zero_new_buffers(struct page *page, unsigned from, unsigned to)
 982 {
 983         unsigned int block_start, block_end;
 984         struct buffer_head *head, *bh;
 985
 986         BUG_ON(!PageLocked(page));
 987         if (!page_has_buffers(page))
 988                 return;
 989
 990         bh = head = page_buffers(page);
 991         block_start = 0;
 992         do {
 993                 block_end = block_start + bh->b_size;
 994
 995                 if (buffer_new(bh)) {
 996                         if (block_end > from && block_start < to) {
 997                                 if (!PageUptodate(page)) {
 998                                         unsigned start, end;
 999
1000                                         start = max(from, block_start);
1001                                         end = min(to, block_end);
1002
1003                                         zero_user_segment(page, start, end);
1004                                         set_buffer_uptodate(bh);
1005                                 }
1006
1007                                 clear_buffer_new(bh);
1008                                 mark_buffer_dirty(bh);
1009                         }
1010                 }
1011
1012                 block_start = block_end;
1013                 bh = bh->b_this_page;
1014         } while (bh != head);
1015 }
1016
1017 /*
1018  * Only called when we have a failure during allocating write to write
1019  * zero's to the newly allocated region.
1020  */
1021 static void ocfs2_write_failure(struct inode *inode,
1022                                 struct ocfs2_write_ctxt *wc,
1023                                 loff_t user_pos, unsigned user_len)
1024 {
1025         int i;
1026         unsigned from = user_pos & (PAGE_CACHE_SIZE - 1),
1027                 to = user_pos + user_len;
1028         struct page *tmppage;
1029
1030         ocfs2_zero_new_buffers(wc->w_target_page, from, to);
1031
1032         for(i = 0; i < wc->w_num_pages; i++) {
1033                 tmppage = wc->w_pages[i];
1034
1035                 if (page_has_buffers(tmppage)) {
1036                         if (ocfs2_should_order_data(inode))
1037                                 ocfs2_jbd2_file_inode(wc->w_handle, inode);
1038
1039                         block_commit_write(tmppage, from, to);
1040                 }
1041         }
1042 }
1043
1044 static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno,
1045                                         struct ocfs2_write_ctxt *wc,
1046                                         struct page *page, u32 cpos,
1047                                         loff_t user_pos, unsigned user_len,
1048                                         int new)
1049 {
1050         int ret;
1051         unsigned int map_from = 0, map_to = 0;
1052         unsigned int cluster_start, cluster_end;
1053         unsigned int user_data_from = 0, user_data_to = 0;
1054
1055         ocfs2_figure_cluster_boundaries(OCFS2_SB(inode->i_sb), cpos,
1056                                         &cluster_start, &cluster_end);
1057
1058         /* treat the write as new if the a hole/lseek spanned across
1059          * the page boundary.
1060          */
1061         new = new | ((i_size_read(inode) <= page_offset(page)) &&
1062                         (page_offset(page) <= user_pos));
1063
1064         if (page == wc->w_target_page) {
1065                 map_from = user_pos & (PAGE_CACHE_SIZE - 1);
1066                 map_to = map_from + user_len;
1067
1068                 if (new)
1069                         ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1070                                                     cluster_start, cluster_end,
1071                                                     new);
1072                 else
1073                         ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1074                                                     map_from, map_to, new);
1075                 if (ret) {
1076                         mlog_errno(ret);
1077                         goto out;
1078                 }
1079
1080                 user_data_from = map_from;
1081                 user_data_to = map_to;
1082                 if (new) {
1083                         map_from = cluster_start;
1084                         map_to = cluster_end;
1085                 }
1086         } else {
1087                 /*
1088                  * If we haven't allocated the new page yet, we
1089                  * shouldn't be writing it out without copying user
1090                  * data. This is likely a math error from the caller.
1091                  */
1092                 BUG_ON(!new);
1093
1094                 map_from = cluster_start;
1095                 map_to = cluster_end;
1096
1097                 ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1098                                             cluster_start, cluster_end, new);
1099                 if (ret) {
1100                         mlog_errno(ret);
1101                         goto out;
1102                 }
1103         }
1104
1105         /*
1106          * Parts of newly allocated pages need to be zero'd.
1107          *
1108          * Above, we have also rewritten 'to' and 'from' - as far as
1109          * the rest of the function is concerned, the entire cluster
1110          * range inside of a page needs to be written.
1111          *
1112          * We can skip this if the page is up to date - it's already
1113          * been zero'd from being read in as a hole.
1114          */
1115         if (new && !PageUptodate(page))
1116                 ocfs2_clear_page_regions(page, OCFS2_SB(inode->i_sb),
1117                                          cpos, user_data_from, user_data_to);
1118
1119         flush_dcache_page(page);
1120
1121 out:
1122         return ret;
1123 }
1124
1125 /*
1126  * This function will only grab one clusters worth of pages.
1127  */
1128 static int ocfs2_grab_pages_for_write(struct address_space *mapping,
1129                                       struct ocfs2_write_ctxt *wc,
1130                                       u32 cpos, loff_t user_pos,
1131                                       unsigned user_len, int new,
1132                                       struct page *mmap_page)
1133 {
1134         int ret = 0, i;
1135         unsigned long start, target_index, end_index, index;
1136         struct inode *inode = mapping->host;
1137         loff_t last_byte;
1138
1139         target_index = user_pos >> PAGE_CACHE_SHIFT;
1140
1141         /*
1142          * Figure out how many pages we'll be manipulating here. For
1143          * non allocating write, we just change the one
1144          * page. Otherwise, we'll need a whole clusters worth.  If we're
1145          * writing past i_size, we only need enough pages to cover the
1146          * last page of the write.
1147          */
1148         if (new) {
1149                 wc->w_num_pages = ocfs2_pages_per_cluster(inode->i_sb);
1150                 start = ocfs2_align_clusters_to_page_index(inode->i_sb, cpos);
1151                 /*
1152                  * We need the index *past* the last page we could possibly
1153                  * touch.  This is the page past the end of the write or
1154                  * i_size, whichever is greater.
1155                  */
1156                 last_byte = max(user_pos + user_len, i_size_read(inode));
1157                 BUG_ON(last_byte < 1);
1158                 end_index = ((last_byte - 1) >> PAGE_CACHE_SHIFT) + 1;
1159                 if ((start + wc->w_num_pages) > end_index)
1160                         wc->w_num_pages = end_index - start;
1161         } else {
1162                 wc->w_num_pages = 1;
1163                 start = target_index;
1164         }
1165
1166         for(i = 0; i < wc->w_num_pages; i++) {
1167                 index = start + i;
1168
1169                 if (index == target_index && mmap_page) {
1170                         /*
1171                          * ocfs2_pagemkwrite() is a little different
1172                          * and wants us to directly use the page
1173                          * passed in.
1174                          */
1175                         lock_page(mmap_page);
1176
1177                         /* Exit and let the caller retry */
1178                         if (mmap_page->mapping != mapping) {
1179                                 WARN_ON(mmap_page->mapping);
1180                                 unlock_page(mmap_page);
1181                                 ret = -EAGAIN;
1182                                 goto out;
1183                         }
1184
1185                         page_cache_get(mmap_page);
1186                         wc->w_pages[i] = mmap_page;
1187                         wc->w_target_locked = true;
1188                 } else {
1189                         wc->w_pages[i] = find_or_create_page(mapping, index,
1190                                                              GFP_NOFS);
1191                         if (!wc->w_pages[i]) {
1192                                 ret = -ENOMEM;
1193                                 mlog_errno(ret);
1194                                 goto out;
1195                         }
1196                 }
1197                 wait_for_stable_page(wc->w_pages[i]);
1198
1199                 if (index == target_index)
1200                         wc->w_target_page = wc->w_pages[i];
1201         }
1202 out:
1203         if (ret)
1204                 wc->w_target_locked = false;
1205         return ret;
1206 }
1207
1208 /*
1209  * Prepare a single cluster for write one cluster into the file.
1210  */
1211 static int ocfs2_write_cluster(struct address_space *mapping,
1212                                u32 phys, unsigned int unwritten,
1213                                unsigned int should_zero,
1214                                struct ocfs2_alloc_context *data_ac,
1215                                struct ocfs2_alloc_context *meta_ac,
1216                                struct ocfs2_write_ctxt *wc, u32 cpos,
1217                                loff_t user_pos, unsigned user_len)
1218 {
1219         int ret, i, new;
1220         u64 v_blkno, p_blkno;
1221         struct inode *inode = mapping->host;
1222         struct ocfs2_extent_tree et;
1223
1224         new = phys == 0 ? 1 : 0;
1225         if (new) {
1226                 u32 tmp_pos;
1227
1228                 /*
1229                  * This is safe to call with the page locks - it won't take
1230                  * any additional semaphores or cluster locks.
1231                  */
1232                 tmp_pos = cpos;
1233                 ret = ocfs2_add_inode_data(OCFS2_SB(inode->i_sb), inode,
1234                                            &tmp_pos, 1, 0, wc->w_di_bh,
1235                                            wc->w_handle, data_ac,
1236                                            meta_ac, NULL);
1237                 /*
1238                  * This shouldn't happen because we must have already
1239                  * calculated the correct meta data allocation required. The
1240                  * internal tree allocation code should know how to increase
1241                  * transaction credits itself.
1242                  *
1243                  * If need be, we could handle -EAGAIN for a
1244                  * RESTART_TRANS here.
1245                  */
1246                 mlog_bug_on_msg(ret == -EAGAIN,
1247                                 "Inode %llu: EAGAIN return during allocation.\n",
1248                                 (unsigned long long)OCFS2_I(inode)->ip_blkno);
1249                 if (ret < 0) {
1250                         mlog_errno(ret);
1251                         goto out;
1252                 }
1253         } else if (unwritten) {
1254                 ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
1255                                               wc->w_di_bh);
1256                 ret = ocfs2_mark_extent_written(inode, &et,
1257                                                 wc->w_handle, cpos, 1, phys,
1258                                                 meta_ac, &wc->w_dealloc);
1259                 if (ret < 0) {
1260                         mlog_errno(ret);
1261                         goto out;
1262                 }
1263         }
1264
1265         if (should_zero)
1266                 v_blkno = ocfs2_clusters_to_blocks(inode->i_sb, cpos);
1267         else
1268                 v_blkno = user_pos >> inode->i_sb->s_blocksize_bits;
1269
1270         /*
1271          * The only reason this should fail is due to an inability to
1272          * find the extent added.
1273          */
1274         ret = ocfs2_extent_map_get_blocks(inode, v_blkno, &p_blkno, NULL,
1275                                           NULL);
1276         if (ret < 0) {
1277                 ocfs2_error(inode->i_sb, "Corrupting extend for inode %llu, "
1278                             "at logical block %llu",
1279                             (unsigned long long)OCFS2_I(inode)->ip_blkno,
1280                             (unsigned long long)v_blkno);
1281                 goto out;
1282         }
1283
1284         BUG_ON(p_blkno == 0);
1285
1286         for(i = 0; i < wc->w_num_pages; i++) {
1287                 int tmpret;
1288
1289                 tmpret = ocfs2_prepare_page_for_write(inode, &p_blkno, wc,
1290                                                       wc->w_pages[i], cpos,
1291                                                       user_pos, user_len,
1292                                                       should_zero);
1293                 if (tmpret) {
1294                         mlog_errno(tmpret);
1295                         if (ret == 0)
1296                                 ret = tmpret;
1297                 }
1298         }
1299
1300         /*
1301          * We only have cleanup to do in case of allocating write.
1302          */
1303         if (ret && new)
1304                 ocfs2_write_failure(inode, wc, user_pos, user_len);
1305
1306 out:
1307
1308         return ret;
1309 }
1310
1311 static int ocfs2_write_cluster_by_desc(struct address_space *mapping,
1312                                        struct ocfs2_alloc_context *data_ac,
1313                                        struct ocfs2_alloc_context *meta_ac,
1314                                        struct ocfs2_write_ctxt *wc,
1315                                        loff_t pos, unsigned len)
1316 {
1317         int ret, i;
1318         loff_t cluster_off;
1319         unsigned int local_len = len;
1320         struct ocfs2_write_cluster_desc *desc;
1321         struct ocfs2_super *osb = OCFS2_SB(mapping->host->i_sb);
1322
1323         for (i = 0; i < wc->w_clen; i++) {
1324                 desc = &wc->w_desc[i];
1325
1326                 /*
1327                  * We have to make sure that the total write passed in
1328                  * doesn't extend past a single cluster.
1329                  */
1330                 local_len = len;
1331                 cluster_off = pos & (osb->s_clustersize - 1);
1332                 if ((cluster_off + local_len) > osb->s_clustersize)
1333                         local_len = osb->s_clustersize - cluster_off;
1334
1335                 ret = ocfs2_write_cluster(mapping, desc->c_phys,
1336                                           desc->c_unwritten,
1337                                           desc->c_needs_zero,
1338                                           data_ac, meta_ac,
1339                                           wc, desc->c_cpos, pos, local_len);
1340                 if (ret) {
1341                         mlog_errno(ret);
1342                         goto out;
1343                 }
1344
1345                 len -= local_len;
1346                 pos += local_len;
1347         }
1348
1349         ret = 0;
1350 out:
1351         return ret;
1352 }
1353
1354 /*
1355  * ocfs2_write_end() wants to know which parts of the target page it
1356  * should complete the write on. It's easiest to compute them ahead of
1357  * time when a more complete view of the write is available.
1358  */
1359 static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
1360                                         struct ocfs2_write_ctxt *wc,
1361                                         loff_t pos, unsigned len, int alloc)
1362 {
1363         struct ocfs2_write_cluster_desc *desc;
1364
1365         wc->w_target_from = pos & (PAGE_CACHE_SIZE - 1);
1366         wc->w_target_to = wc->w_target_from + len;
1367
1368         if (alloc == 0)
1369                 return;
1370
1371         /*
1372          * Allocating write - we may have different boundaries based
1373          * on page size and cluster size.
1374          *
1375          * NOTE: We can no longer compute one value from the other as
1376          * the actual write length and user provided length may be
1377          * different.
1378          */
1379
1380         if (wc->w_large_pages) {
1381                 /*
1382                  * We only care about the 1st and last cluster within
1383                  * our range and whether they should be zero'd or not. Either
1384                  * value may be extended out to the start/end of a
1385                  * newly allocated cluster.
1386                  */
1387                 desc = &wc->w_desc[0];
1388                 if (desc->c_needs_zero)
1389                         ocfs2_figure_cluster_boundaries(osb,
1390                                                         desc->c_cpos,
1391                                                         &wc->w_target_from,
1392                                                         NULL);
1393
1394                 desc = &wc->w_desc[wc->w_clen - 1];
1395                 if (desc->c_needs_zero)
1396                         ocfs2_figure_cluster_boundaries(osb,
1397                                                         desc->c_cpos,
1398                                                         NULL,
1399                                                         &wc->w_target_to);
1400         } else {
1401                 wc->w_target_from = 0;
1402                 wc->w_target_to = PAGE_CACHE_SIZE;
1403         }
1404 }
1405
1406 /*
1407  * Populate each single-cluster write descriptor in the write context
1408  * with information about the i/o to be done.
1409  *
1410  * Returns the number of clusters that will have to be allocated, as
1411  * well as a worst case estimate of the number of extent records that
1412  * would have to be created during a write to an unwritten region.
1413  */
1414 static int ocfs2_populate_write_desc(struct inode *inode,
1415                                      struct ocfs2_write_ctxt *wc,
1416                                      unsigned int *clusters_to_alloc,
1417                                      unsigned int *extents_to_split)
1418 {
1419         int ret;
1420         struct ocfs2_write_cluster_desc *desc;
1421         unsigned int num_clusters = 0;
1422         unsigned int ext_flags = 0;
1423         u32 phys = 0;
1424         int i;
1425
1426         *clusters_to_alloc = 0;
1427         *extents_to_split = 0;
1428
1429         for (i = 0; i < wc->w_clen; i++) {
1430                 desc = &wc->w_desc[i];
1431                 desc->c_cpos = wc->w_cpos + i;
1432
1433                 if (num_clusters == 0) {
1434                         /*
1435                          * Need to look up the next extent record.
1436                          */
1437                         ret = ocfs2_get_clusters(inode, desc->c_cpos, &phys,
1438                                                  &num_clusters, &ext_flags);
1439                         if (ret) {
1440                                 mlog_errno(ret);
1441                                 goto out;
1442                         }
1443
1444                         /* We should already CoW the refcountd extent. */
1445                         BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
1446
1447                         /*
1448                          * Assume worst case - that we're writing in
1449                          * the middle of the extent.
1450                          *
1451                          * We can assume that the write proceeds from
1452                          * left to right, in which case the extent
1453                          * insert code is smart enough to coalesce the
1454                          * next splits into the previous records created.
1455                          */
1456                         if (ext_flags & OCFS2_EXT_UNWRITTEN)
1457                                 *extents_to_split = *extents_to_split + 2;
1458                 } else if (phys) {
1459                         /*
1460                          * Only increment phys if it doesn't describe
1461                          * a hole.
1462                          */
1463                         phys++;
1464                 }
1465
1466                 /*
1467                  * If w_first_new_cpos is < UINT_MAX, we have a non-sparse
1468                  * file that got extended.  w_first_new_cpos tells us
1469                  * where the newly allocated clusters are so we can
1470                  * zero them.
1471                  */
1472                 if (desc->c_cpos >= wc->w_first_new_cpos) {
1473                         BUG_ON(phys == 0);
1474                         desc->c_needs_zero = 1;
1475                 }
1476
1477                 desc->c_phys = phys;
1478                 if (phys == 0) {
1479                         desc->c_new = 1;
1480                         desc->c_needs_zero = 1;
1481                         *clusters_to_alloc = *clusters_to_alloc + 1;
1482                 }
1483
1484                 if (ext_flags & OCFS2_EXT_UNWRITTEN) {
1485                         desc->c_unwritten = 1;
1486                         desc->c_needs_zero = 1;
1487                 }
1488
1489                 num_clusters--;
1490         }
1491
1492         ret = 0;
1493 out:
1494         return ret;
1495 }
1496
1497 static int ocfs2_write_begin_inline(struct address_space *mapping,
1498                                     struct inode *inode,
1499                                     struct ocfs2_write_ctxt *wc)
1500 {
1501         int ret;
1502         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1503         struct page *page;
1504         handle_t *handle;
1505         struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1506
1507         page = find_or_create_page(mapping, 0, GFP_NOFS);
1508         if (!page) {
1509                 ret = -ENOMEM;
1510                 mlog_errno(ret);
1511                 goto out;
1512         }
1513         /*
1514          * If we don't set w_num_pages then this page won't get unlocked
1515          * and freed on cleanup of the write context.
1516          */
1517         wc->w_pages[0] = wc->w_target_page = page;
1518         wc->w_num_pages = 1;
1519
1520         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1521         if (IS_ERR(handle)) {
1522                 ret = PTR_ERR(handle);
1523                 mlog_errno(ret);
1524                 goto out;
1525         }
1526
1527         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
1528                                       OCFS2_JOURNAL_ACCESS_WRITE);
1529         if (ret) {
1530                 ocfs2_commit_trans(osb, handle);
1531
1532                 mlog_errno(ret);
1533                 goto out;
1534         }
1535
1536         if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
1537                 ocfs2_set_inode_data_inline(inode, di);
1538
1539         if (!PageUptodate(page)) {
1540                 ret = ocfs2_read_inline_data(inode, page, wc->w_di_bh);
1541                 if (ret) {
1542                         ocfs2_commit_trans(osb, handle);
1543
1544                         goto out;
1545                 }
1546         }
1547
1548         wc->w_handle = handle;
1549 out:
1550         return ret;
1551 }
1552
1553 int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size)
1554 {
1555         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1556
1557         if (new_size <= le16_to_cpu(di->id2.i_data.id_count))
1558                 return 1;
1559         return 0;
1560 }
1561
1562 static int ocfs2_try_to_write_inline_data(struct address_space *mapping,
1563                                           struct inode *inode, loff_t pos,
1564                                           unsigned len, struct page *mmap_page,
1565                                           struct ocfs2_write_ctxt *wc)
1566 {
1567         int ret, written = 0;
1568         loff_t end = pos + len;
1569         struct ocfs2_inode_info *oi = OCFS2_I(inode);
1570         struct ocfs2_dinode *di = NULL;
1571
1572         trace_ocfs2_try_to_write_inline_data((unsigned long long)oi->ip_blkno,
1573                                              len, (unsigned long long)pos,
1574                                              oi->ip_dyn_features);
1575
1576         /*
1577          * Handle inodes which already have inline data 1st.
1578          */
1579         if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1580                 if (mmap_page == NULL &&
1581                     ocfs2_size_fits_inline_data(wc->w_di_bh, end))
1582                         goto do_inline_write;
1583
1584                 /*
1585                  * The write won't fit - we have to give this inode an
1586                  * inline extent list now.
1587                  */
1588                 ret = ocfs2_convert_inline_data_to_extents(inode, wc->w_di_bh);
1589                 if (ret)
1590                         mlog_errno(ret);
1591                 goto out;
1592         }
1593
1594         /*
1595          * Check whether the inode can accept inline data.
1596          */
1597         if (oi->ip_clusters != 0 || i_size_read(inode) != 0)
1598                 return 0;
1599
1600         /*
1601          * Check whether the write can fit.
1602          */
1603         di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1604         if (mmap_page ||
1605             end > ocfs2_max_inline_data_with_xattr(inode->i_sb, di))
1606                 return 0;
1607
1608 do_inline_write:
1609         ret = ocfs2_write_begin_inline(mapping, inode, wc);
1610         if (ret) {
1611                 mlog_errno(ret);
1612                 goto out;
1613         }
1614
1615         /*
1616          * This signals to the caller that the data can be written
1617          * inline.
1618          */
1619         written = 1;
1620 out:
1621         return written ? written : ret;
1622 }
1623
1624 /*
1625  * This function only does anything for file systems which can't
1626  * handle sparse files.
1627  *
1628  * What we want to do here is fill in any hole between the current end
1629  * of allocation and the end of our write. That way the rest of the
1630  * write path can treat it as an non-allocating write, which has no
1631  * special case code for sparse/nonsparse files.
1632  */
1633 static int ocfs2_expand_nonsparse_inode(struct inode *inode,
1634                                         struct buffer_head *di_bh,
1635                                         loff_t pos, unsigned len,
1636                                         struct ocfs2_write_ctxt *wc)
1637 {
1638         int ret;
1639         loff_t newsize = pos + len;
1640
1641         BUG_ON(ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)));
1642
1643         if (newsize <= i_size_read(inode))
1644                 return 0;
1645
1646         ret = ocfs2_extend_no_holes(inode, di_bh, newsize, pos);
1647         if (ret)
1648                 mlog_errno(ret);
1649
1650         wc->w_first_new_cpos =
1651                 ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode));
1652
1653         return ret;
1654 }
1655
1656 static int ocfs2_zero_tail(struct inode *inode, struct buffer_head *di_bh,
1657                            loff_t pos)
1658 {
1659         int ret = 0;
1660
1661         BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)));
1662         if (pos > i_size_read(inode))
1663                 ret = ocfs2_zero_extend(inode, di_bh, pos);
1664
1665         return ret;
1666 }
1667
1668 /*
1669  * Try to flush truncate logs if we can free enough clusters from it.
1670  * As for return value, "< 0" means error, "0" no space and "1" means
1671  * we have freed enough spaces and let the caller try to allocate again.
1672  */
1673 static int ocfs2_try_to_free_truncate_log(struct ocfs2_super *osb,
1674                                           unsigned int needed)
1675 {
1676         tid_t target;
1677         int ret = 0;
1678         unsigned int truncated_clusters;
1679
1680         mutex_lock(&osb->osb_tl_inode->i_mutex);
1681         truncated_clusters = osb->truncated_clusters;
1682         mutex_unlock(&osb->osb_tl_inode->i_mutex);
1683
1684         /*
1685          * Check whether we can succeed in allocating if we free
1686          * the truncate log.
1687          */
1688         if (truncated_clusters < needed)
1689                 goto out;
1690
1691         ret = ocfs2_flush_truncate_log(osb);
1692         if (ret) {
1693                 mlog_errno(ret);
1694                 goto out;
1695         }
1696
1697         if (jbd2_journal_start_commit(osb->journal->j_journal, &target)) {
1698                 jbd2_log_wait_commit(osb->journal->j_journal, target);
1699                 ret = 1;
1700         }
1701 out:
1702         return ret;
1703 }
1704
1705 int ocfs2_write_begin_nolock(struct file *filp,
1706                              struct address_space *mapping,
1707                              loff_t pos, unsigned len, unsigned flags,
1708                              struct page **pagep, void **fsdata,
1709                              struct buffer_head *di_bh, struct page *mmap_page)
1710 {
1711         int ret, cluster_of_pages, credits = OCFS2_INODE_UPDATE_CREDITS;
1712         unsigned int clusters_to_alloc, extents_to_split, clusters_need = 0;
1713         struct ocfs2_write_ctxt *wc;
1714         struct inode *inode = mapping->host;
1715         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1716         struct ocfs2_dinode *di;
1717         struct ocfs2_alloc_context *data_ac = NULL;
1718         struct ocfs2_alloc_context *meta_ac = NULL;
1719         handle_t *handle;
1720         struct ocfs2_extent_tree et;
1721         int try_free = 1, ret1;
1722
1723 try_again:
1724         ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
1725         if (ret) {
1726                 mlog_errno(ret);
1727                 return ret;
1728         }
1729
1730         if (ocfs2_supports_inline_data(osb)) {
1731                 ret = ocfs2_try_to_write_inline_data(mapping, inode, pos, len,
1732                                                      mmap_page, wc);
1733                 if (ret == 1) {
1734                         ret = 0;
1735                         goto success;
1736                 }
1737                 if (ret < 0) {
1738                         mlog_errno(ret);
1739                         goto out;
1740                 }
1741         }
1742
1743         if (ocfs2_sparse_alloc(osb))
1744                 ret = ocfs2_zero_tail(inode, di_bh, pos);
1745         else
1746                 ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos, len,
1747                                                    wc);
1748         if (ret) {
1749                 mlog_errno(ret);
1750                 goto out;
1751         }
1752
1753         ret = ocfs2_check_range_for_refcount(inode, pos, len);
1754         if (ret < 0) {
1755                 mlog_errno(ret);
1756                 goto out;
1757         } else if (ret == 1) {
1758                 clusters_need = wc->w_clen;
1759                 ret = ocfs2_refcount_cow(inode, filp, di_bh,
1760                                          wc->w_cpos, wc->w_clen, UINT_MAX);
1761                 if (ret) {
1762                         mlog_errno(ret);
1763                         goto out;
1764                 }
1765         }
1766
1767         ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc,
1768                                         &extents_to_split);
1769         if (ret) {
1770                 mlog_errno(ret);
1771                 goto out;
1772         }
1773         clusters_need += clusters_to_alloc;
1774
1775         di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1776
1777         trace_ocfs2_write_begin_nolock(
1778                         (unsigned long long)OCFS2_I(inode)->ip_blkno,
1779                         (long long)i_size_read(inode),
1780                         le32_to_cpu(di->i_clusters),
1781                         pos, len, flags, mmap_page,
1782                         clusters_to_alloc, extents_to_split);
1783
1784         /*
1785          * We set w_target_from, w_target_to here so that
1786          * ocfs2_write_end() knows which range in the target page to
1787          * write out. An allocation requires that we write the entire
1788          * cluster range.
1789          */
1790         if (clusters_to_alloc || extents_to_split) {
1791                 /*
1792                  * XXX: We are stretching the limits of
1793                  * ocfs2_lock_allocators(). It greatly over-estimates
1794                  * the work to be done.
1795                  */
1796                 ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
1797                                               wc->w_di_bh);
1798                 ret = ocfs2_lock_allocators(inode, &et,
1799                                             clusters_to_alloc, extents_to_split,
1800                                             &data_ac, &meta_ac);
1801                 if (ret) {
1802                         mlog_errno(ret);
1803                         goto out;
1804                 }
1805
1806                 if (data_ac)
1807                         data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
1808
1809                 credits = ocfs2_calc_extend_credits(inode->i_sb,
1810                                                     &di->id2.i_list,
1811                                                     clusters_to_alloc);
1812
1813         }
1814
1815         /*
1816          * We have to zero sparse allocated clusters, unwritten extent clusters,
1817          * and non-sparse clusters we just extended.  For non-sparse writes,
1818          * we know zeros will only be needed in the first and/or last cluster.
1819          */
1820         if (clusters_to_alloc || extents_to_split ||
1821             (wc->w_clen && (wc->w_desc[0].c_needs_zero ||
1822                             wc->w_desc[wc->w_clen - 1].c_needs_zero)))
1823                 cluster_of_pages = 1;
1824         else
1825                 cluster_of_pages = 0;
1826
1827         ocfs2_set_target_boundaries(osb, wc, pos, len, cluster_of_pages);
1828
1829         handle = ocfs2_start_trans(osb, credits);
1830         if (IS_ERR(handle)) {
1831                 ret = PTR_ERR(handle);
1832                 mlog_errno(ret);
1833                 goto out;
1834         }
1835
1836         wc->w_handle = handle;
1837
1838         if (clusters_to_alloc) {
1839                 ret = dquot_alloc_space_nodirty(inode,
1840                         ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
1841                 if (ret)
1842                         goto out_commit;
1843         }
1844         /*
1845          * We don't want this to fail in ocfs2_write_end(), so do it
1846          * here.
1847          */
1848         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
1849                                       OCFS2_JOURNAL_ACCESS_WRITE);
1850         if (ret) {
1851                 mlog_errno(ret);
1852                 goto out_quota;
1853         }
1854
1855         /*
1856          * Fill our page array first. That way we've grabbed enough so
1857          * that we can zero and flush if we error after adding the
1858          * extent.
1859          */
1860         ret = ocfs2_grab_pages_for_write(mapping, wc, wc->w_cpos, pos, len,
1861                                          cluster_of_pages, mmap_page);
1862         if (ret && ret != -EAGAIN) {
1863                 mlog_errno(ret);
1864                 goto out_quota;
1865         }
1866
1867         /*
1868          * ocfs2_grab_pages_for_write() returns -EAGAIN if it could not lock
1869          * the target page. In this case, we exit with no error and no target
1870          * page. This will trigger the caller, page_mkwrite(), to re-try
1871          * the operation.
1872          */
1873         if (ret == -EAGAIN) {
1874                 BUG_ON(wc->w_target_page);
1875                 ret = 0;
1876                 goto out_quota;
1877         }
1878
1879         ret = ocfs2_write_cluster_by_desc(mapping, data_ac, meta_ac, wc, pos,
1880                                           len);
1881         if (ret) {
1882                 mlog_errno(ret);
1883                 goto out_quota;
1884         }
1885
1886         if (data_ac)
1887                 ocfs2_free_alloc_context(data_ac);
1888         if (meta_ac)
1889                 ocfs2_free_alloc_context(meta_ac);
1890
1891 success:
1892         *pagep = wc->w_target_page;
1893         *fsdata = wc;
1894         return 0;
1895 out_quota:
1896         if (clusters_to_alloc)
1897                 dquot_free_space(inode,
1898                           ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
1899 out_commit:
1900         ocfs2_commit_trans(osb, handle);
1901
1902 out:
1903         ocfs2_free_write_ctxt(wc);
1904
1905         if (data_ac)
1906                 ocfs2_free_alloc_context(data_ac);
1907         if (meta_ac)
1908                 ocfs2_free_alloc_context(meta_ac);
1909
1910         if (ret == -ENOSPC && try_free) {
1911                 /*
1912                  * Try to free some truncate log so that we can have enough
1913                  * clusters to allocate.
1914                  */
1915                 try_free = 0;
1916
1917                 ret1 = ocfs2_try_to_free_truncate_log(osb, clusters_need);
1918                 if (ret1 == 1)
1919                         goto try_again;
1920
1921                 if (ret1 < 0)
1922                         mlog_errno(ret1);
1923         }
1924
1925         return ret;
1926 }
1927
1928 static int ocfs2_write_begin(struct file *file, struct address_space *mapping,
1929                              loff_t pos, unsigned len, unsigned flags,
1930                              struct page **pagep, void **fsdata)
1931 {
1932         int ret;
1933         struct buffer_head *di_bh = NULL;
1934         struct inode *inode = mapping->host;
1935
1936         ret = ocfs2_inode_lock(inode, &di_bh, 1);
1937         if (ret) {
1938                 mlog_errno(ret);
1939                 return ret;
1940         }
1941
1942         /*
1943          * Take alloc sem here to prevent concurrent lookups. That way
1944          * the mapping, zeroing and tree manipulation within
1945          * ocfs2_write() will be safe against ->readpage(). This
1946          * should also serve to lock out allocation from a shared
1947          * writeable region.
1948          */
1949         down_write(&OCFS2_I(inode)->ip_alloc_sem);
1950
1951         ret = ocfs2_write_begin_nolock(file, mapping, pos, len, flags, pagep,
1952                                        fsdata, di_bh, NULL);
1953         if (ret) {
1954                 mlog_errno(ret);
1955                 goto out_fail;
1956         }
1957
1958         brelse(di_bh);
1959
1960         return 0;
1961
1962 out_fail:
1963         up_write(&OCFS2_I(inode)->ip_alloc_sem);
1964
1965         brelse(di_bh);
1966         ocfs2_inode_unlock(inode, 1);
1967
1968         return ret;
1969 }
1970
1971 static void ocfs2_write_end_inline(struct inode *inode, loff_t pos,
1972                                    unsigned len, unsigned *copied,
1973                                    struct ocfs2_dinode *di,
1974                                    struct ocfs2_write_ctxt *wc)
1975 {
1976         void *kaddr;
1977
1978         if (unlikely(*copied < len)) {
1979                 if (!PageUptodate(wc->w_target_page)) {
1980                         *copied = 0;
1981                         return;
1982                 }
1983         }
1984
1985         kaddr = kmap_atomic(wc->w_target_page);
1986         memcpy(di->id2.i_data.id_data + pos, kaddr + pos, *copied);
1987         kunmap_atomic(kaddr);
1988
1989         trace_ocfs2_write_end_inline(
1990              (unsigned long long)OCFS2_I(inode)->ip_blkno,
1991              (unsigned long long)pos, *copied,
1992              le16_to_cpu(di->id2.i_data.id_count),
1993              le16_to_cpu(di->i_dyn_features));
1994 }
1995
1996 int ocfs2_write_end_nolock(struct address_space *mapping,
1997                            loff_t pos, unsigned len, unsigned copied,
1998                            struct page *page, void *fsdata)
1999 {
2000         int i;
2001         unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1);
2002         struct inode *inode = mapping->host;
2003         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2004         struct ocfs2_write_ctxt *wc = fsdata;
2005         struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
2006         handle_t *handle = wc->w_handle;
2007         struct page *tmppage;
2008
2009         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
2010                 ocfs2_write_end_inline(inode, pos, len, &copied, di, wc);
2011                 goto out_write_size;
2012         }
2013
2014         if (unlikely(copied < len)) {
2015                 if (!PageUptodate(wc->w_target_page))
2016                         copied = 0;
2017
2018                 ocfs2_zero_new_buffers(wc->w_target_page, start+copied,
2019                                        start+len);
2020         }
2021         flush_dcache_page(wc->w_target_page);
2022
2023         for(i = 0; i < wc->w_num_pages; i++) {
2024                 tmppage = wc->w_pages[i];
2025
2026                 if (tmppage == wc->w_target_page) {
2027                         from = wc->w_target_from;
2028                         to = wc->w_target_to;
2029
2030                         BUG_ON(from > PAGE_CACHE_SIZE ||
2031                                to > PAGE_CACHE_SIZE ||
2032                                to < from);
2033                 } else {
2034                         /*
2035                          * Pages adjacent to the target (if any) imply
2036                          * a hole-filling write in which case we want
2037                          * to flush their entire range.
2038                          */
2039                         from = 0;
2040                         to = PAGE_CACHE_SIZE;
2041                 }
2042
2043                 if (page_has_buffers(tmppage)) {
2044                         if (ocfs2_should_order_data(inode))
2045                                 ocfs2_jbd2_file_inode(wc->w_handle, inode);
2046                         block_commit_write(tmppage, from, to);
2047                 }
2048         }
2049
2050 out_write_size:
2051         pos += copied;
2052         if (pos > inode->i_size) {
2053                 i_size_write(inode, pos);
2054                 mark_inode_dirty(inode);
2055         }
2056         inode->i_blocks = ocfs2_inode_sector_count(inode);
2057         di->i_size = cpu_to_le64((u64)i_size_read(inode));
2058         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2059         di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec);
2060         di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
2061         ocfs2_journal_dirty(handle, wc->w_di_bh);
2062
2063         ocfs2_commit_trans(osb, handle);
2064
2065         ocfs2_run_deallocs(osb, &wc->w_dealloc);
2066
2067         ocfs2_free_write_ctxt(wc);
2068
2069         return copied;
2070 }
2071
2072 static int ocfs2_write_end(struct file *file, struct address_space *mapping,
2073                            loff_t pos, unsigned len, unsigned copied,
2074                            struct page *page, void *fsdata)
2075 {
2076         int ret;
2077         struct inode *inode = mapping->host;
2078
2079         ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);
2080
2081         up_write(&OCFS2_I(inode)->ip_alloc_sem);
2082         ocfs2_inode_unlock(inode, 1);
2083
2084         return ret;
2085 }
2086
2087 const struct address_space_operations ocfs2_aops = {
2088         .readpage               = ocfs2_readpage,
2089         .readpages              = ocfs2_readpages,
2090         .writepage              = ocfs2_writepage,
2091         .write_begin            = ocfs2_write_begin,
2092         .write_end              = ocfs2_write_end,
2093         .bmap                   = ocfs2_bmap,
2094         .direct_IO              = ocfs2_direct_IO,
2095         .invalidatepage         = ocfs2_invalidatepage,
2096         .releasepage            = ocfs2_releasepage,
2097         .migratepage            = buffer_migrate_page,
2098         .is_partially_uptodate  = block_is_partially_uptodate,
2099         .error_remove_page      = generic_error_remove_page,
2100 };