reiserfs: use generic write

Make reiserfs to write via generic routines.
Original reiserfs write optimized for big writes is deadlock rone

Signed-off-by: Vladimir Saveliev <vs@namesys.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/reiserfs/file.c

@@ -153,608 +153,6 @@ static int reiserfs_sync_file(struct file *p_s_filp,
 	return (n_err < 0) ? -EIO : 0;
 }
 
-/* I really do not want to play with memory shortage right now, so
-   to simplify the code, we are not going to write more than this much pages at
-   a time. This still should considerably improve performance compared to 4k
-   at a time case. This is 32 pages of 4k size. */
-#define REISERFS_WRITE_PAGES_AT_A_TIME (128 * 1024) / PAGE_CACHE_SIZE
-
-/* Allocates blocks for a file to fulfil write request.
-   Maps all unmapped but prepared pages from the list.
-   Updates metadata with newly allocated blocknumbers as needed */
-static int reiserfs_allocate_blocks_for_region(struct reiserfs_transaction_handle *th, struct inode *inode,	/* Inode we work with */
-					       loff_t pos,	/* Writing position */
-					       int num_pages,	/* number of pages write going
-								   to touch */
-					       int write_bytes,	/* amount of bytes to write */
-					       struct page **prepared_pages,	/* array of
-										   prepared pages
-										 */
-					       int blocks_to_allocate	/* Amount of blocks we
-									   need to allocate to
-									   fit the data into file
-									 */
-    )
-{
-	struct cpu_key key;	// cpu key of item that we are going to deal with
-	struct item_head *ih;	// pointer to item head that we are going to deal with
-	struct buffer_head *bh;	// Buffer head that contains items that we are going to deal with
-	__le32 *item;		// pointer to item we are going to deal with
-	INITIALIZE_PATH(path);	// path to item, that we are going to deal with.
-	b_blocknr_t *allocated_blocks;	// Pointer to a place where allocated blocknumbers would be stored.
-	reiserfs_blocknr_hint_t hint;	// hint structure for block allocator.
-	size_t res;		// return value of various functions that we call.
-	int curr_block;		// current block used to keep track of unmapped blocks.
-	int i;			// loop counter
-	int itempos;		// position in item
-	unsigned int from = (pos & (PAGE_CACHE_SIZE - 1));	// writing position in
-	// first page
-	unsigned int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1;	/* last modified byte offset in last page */
-	__u64 hole_size;	// amount of blocks for a file hole, if it needed to be created.
-	int modifying_this_item = 0;	// Flag for items traversal code to keep track
-	// of the fact that we already prepared
-	// current block for journal
-	int will_prealloc = 0;
-	RFALSE(!blocks_to_allocate,
-	       "green-9004: tried to allocate zero blocks?");
-
-	/* only preallocate if this is a small write */
-	if (REISERFS_I(inode)->i_prealloc_count ||
-	    (!(write_bytes & (inode->i_sb->s_blocksize - 1)) &&
-	     blocks_to_allocate <
-	     REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize))
-		will_prealloc =
-		    REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize;
-
-	allocated_blocks = kmalloc((blocks_to_allocate + will_prealloc) *
-				   sizeof(b_blocknr_t), GFP_NOFS);
-	if (!allocated_blocks)
-		return -ENOMEM;
-
-	/* First we compose a key to point at the writing position, we want to do
-	   that outside of any locking region. */
-	make_cpu_key(&key, inode, pos + 1, TYPE_ANY, 3 /*key length */ );
-
-	/* If we came here, it means we absolutely need to open a transaction,
-	   since we need to allocate some blocks */
-	reiserfs_write_lock(inode->i_sb);	// Journaling stuff and we need that.
-	res = journal_begin(th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1 + 2 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb));	// Wish I know if this number enough
-	if (res)
-		goto error_exit;
-	reiserfs_update_inode_transaction(inode);
-
-	/* Look for the in-tree position of our write, need path for block allocator */
-	res = search_for_position_by_key(inode->i_sb, &key, &path);
-	if (res == IO_ERROR) {
-		res = -EIO;
-		goto error_exit;
-	}
-
-	/* Allocate blocks */
-	/* First fill in "hint" structure for block allocator */
-	hint.th = th;		// transaction handle.
-	hint.path = &path;	// Path, so that block allocator can determine packing locality or whatever it needs to determine.
-	hint.inode = inode;	// Inode is needed by block allocator too.
-	hint.search_start = 0;	// We have no hint on where to search free blocks for block allocator.
-	hint.key = key.on_disk_key;	// on disk key of file.
-	hint.block = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);	// Number of disk blocks this file occupies already.
-	hint.formatted_node = 0;	// We are allocating blocks for unformatted node.
-	hint.preallocate = will_prealloc;
-
-	/* Call block allocator to allocate blocks */
-	res =
-	    reiserfs_allocate_blocknrs(&hint, allocated_blocks,
-				       blocks_to_allocate, blocks_to_allocate);
-	if (res != CARRY_ON) {
-		if (res == NO_DISK_SPACE) {
-			/* We flush the transaction in case of no space. This way some
-			   blocks might become free */
-			SB_JOURNAL(inode->i_sb)->j_must_wait = 1;
-			res = restart_transaction(th, inode, &path);
-			if (res)
-				goto error_exit;
-
-			/* We might have scheduled, so search again */
-			res =
-			    search_for_position_by_key(inode->i_sb, &key,
-						       &path);
-			if (res == IO_ERROR) {
-				res = -EIO;
-				goto error_exit;
-			}
-
-			/* update changed info for hint structure. */
-			res =
-			    reiserfs_allocate_blocknrs(&hint, allocated_blocks,
-						       blocks_to_allocate,
-						       blocks_to_allocate);
-			if (res != CARRY_ON) {
-				res = res == QUOTA_EXCEEDED ? -EDQUOT : -ENOSPC;
-				pathrelse(&path);
-				goto error_exit;
-			}
-		} else {
-			res = res == QUOTA_EXCEEDED ? -EDQUOT : -ENOSPC;
-			pathrelse(&path);
-			goto error_exit;
-		}
-	}
-#ifdef __BIG_ENDIAN
-	// Too bad, I have not found any way to convert a given region from
-	// cpu format to little endian format
-	{
-		int i;
-		for (i = 0; i < blocks_to_allocate; i++)
-			allocated_blocks[i] = cpu_to_le32(allocated_blocks[i]);
-	}
-#endif
-
-	/* Blocks allocating well might have scheduled and tree might have changed,
-	   let's search the tree again */
-	/* find where in the tree our write should go */
-	res = search_for_position_by_key(inode->i_sb, &key, &path);
-	if (res == IO_ERROR) {
-		res = -EIO;
-		goto error_exit_free_blocks;
-	}
-
-	bh = get_last_bh(&path);	// Get a bufferhead for last element in path.
-	ih = get_ih(&path);	// Get a pointer to last item head in path.
-	item = get_item(&path);	// Get a pointer to last item in path
-
-	/* Let's see what we have found */
-	if (res != POSITION_FOUND) {	/* position not found, this means that we
-					   might need to append file with holes
-					   first */
-		// Since we are writing past the file's end, we need to find out if
-		// there is a hole that needs to be inserted before our writing
-		// position, and how many blocks it is going to cover (we need to
-		//  populate pointers to file blocks representing the hole with zeros)
-
-		{
-			int item_offset = 1;
-			/*
-			 * if ih is stat data, its offset is 0 and we don't want to
-			 * add 1 to pos in the hole_size calculation
-			 */
-			if (is_statdata_le_ih(ih))
-				item_offset = 0;
-			hole_size = (pos + item_offset -
-				     (le_key_k_offset
-				      (get_inode_item_key_version(inode),
-				       &(ih->ih_key)) + op_bytes_number(ih,
-									inode->
-									i_sb->
-									s_blocksize)))
-			    >> inode->i_sb->s_blocksize_bits;
-		}
-
-		if (hole_size > 0) {
-			int to_paste = min_t(__u64, hole_size, MAX_ITEM_LEN(inode->i_sb->s_blocksize) / UNFM_P_SIZE);	// How much data to insert first time.
-			/* area filled with zeroes, to supply as list of zero blocknumbers
-			   We allocate it outside of loop just in case loop would spin for
-			   several iterations. */
-			char *zeros = kzalloc(to_paste * UNFM_P_SIZE, GFP_ATOMIC);	// We cannot insert more than MAX_ITEM_LEN bytes anyway.
-			if (!zeros) {
-				res = -ENOMEM;
-				goto error_exit_free_blocks;
-			}
-			do {
-				to_paste =
-				    min_t(__u64, hole_size,
-					  MAX_ITEM_LEN(inode->i_sb->
-						       s_blocksize) /
-					  UNFM_P_SIZE);
-				if (is_indirect_le_ih(ih)) {
-					/* Ok, there is existing indirect item already. Need to append it */
-					/* Calculate position past inserted item */
-					make_cpu_key(&key, inode,
-						     le_key_k_offset
-						     (get_inode_item_key_version
-						      (inode),
-						      &(ih->ih_key)) +
-						     op_bytes_number(ih,
-								     inode->
-								     i_sb->
-								     s_blocksize),
-						     TYPE_INDIRECT, 3);
-					res =
-					    reiserfs_paste_into_item(th, &path,
-								     &key,
-								     inode,
-								     (char *)
-								     zeros,
-								     UNFM_P_SIZE
-								     *
-								     to_paste);
-					if (res) {
-						kfree(zeros);
-						goto error_exit_free_blocks;
-					}
-				} else if (is_statdata_le_ih(ih)) {
-					/* No existing item, create it */
-					/* item head for new item */
-					struct item_head ins_ih;
-
-					/* create a key for our new item */
-					make_cpu_key(&key, inode, 1,
-						     TYPE_INDIRECT, 3);
-
-					/* Create new item head for our new item */
-					make_le_item_head(&ins_ih, &key,
-							  key.version, 1,
-							  TYPE_INDIRECT,
-							  to_paste *
-							  UNFM_P_SIZE,
-							  0 /* free space */ );
-
-					/* Find where such item should live in the tree */
-					res =
-					    search_item(inode->i_sb, &key,
-							&path);
-					if (res != ITEM_NOT_FOUND) {
-						/* item should not exist, otherwise we have error */
-						if (res != -ENOSPC) {
-							reiserfs_warning(inode->
-									 i_sb,
-									 "green-9008: search_by_key (%K) returned %d",
-									 &key,
-									 res);
-						}
-						res = -EIO;
-						kfree(zeros);
-						goto error_exit_free_blocks;
-					}
-					res =
-					    reiserfs_insert_item(th, &path,
-								 &key, &ins_ih,
-								 inode,
-								 (char *)zeros);
-				} else {
-					reiserfs_panic(inode->i_sb,
-						       "green-9011: Unexpected key type %K\n",
-						       &key);
-				}
-				if (res) {
-					kfree(zeros);
-					goto error_exit_free_blocks;
-				}
-				/* Now we want to check if transaction is too full, and if it is
-				   we restart it. This will also free the path. */
-				if (journal_transaction_should_end
-				    (th, th->t_blocks_allocated)) {
-					inode->i_size = cpu_key_k_offset(&key) +
-						(to_paste << inode->i_blkbits);
-					res =
-					    restart_transaction(th, inode,
-								&path);
-					if (res) {
-						pathrelse(&path);
-						kfree(zeros);
-						goto error_exit;
-					}
-				}
-
-				/* Well, need to recalculate path and stuff */
-				set_cpu_key_k_offset(&key,
-						     cpu_key_k_offset(&key) +
-						     (to_paste << inode->
-						      i_blkbits));
-				res =
-				    search_for_position_by_key(inode->i_sb,
-							       &key, &path);
-				if (res == IO_ERROR) {
-					res = -EIO;
-					kfree(zeros);
-					goto error_exit_free_blocks;
-				}
-				bh = get_last_bh(&path);
-				ih = get_ih(&path);
-				item = get_item(&path);
-				hole_size -= to_paste;
-			} while (hole_size);
-			kfree(zeros);
-		}
-	}
-	// Go through existing indirect items first
-	// replace all zeroes with blocknumbers from list
-	// Note that if no corresponding item was found, by previous search,
-	// it means there are no existing in-tree representation for file area
-	// we are going to overwrite, so there is nothing to scan through for holes.
-	for (curr_block = 0, itempos = path.pos_in_item;
-	     curr_block < blocks_to_allocate && res == POSITION_FOUND;) {
-	      retry:
-
-		if (itempos >= ih_item_len(ih) / UNFM_P_SIZE) {
-			/* We run out of data in this indirect item, let's look for another
-			   one. */
-			/* First if we are already modifying current item, log it */
-			if (modifying_this_item) {
-				journal_mark_dirty(th, inode->i_sb, bh);
-				modifying_this_item = 0;
-			}
-			/* Then set the key to look for a new indirect item (offset of old
-			   item is added to old item length */
-			set_cpu_key_k_offset(&key,
-					     le_key_k_offset
-					     (get_inode_item_key_version(inode),
-					      &(ih->ih_key)) +
-					     op_bytes_number(ih,
-							     inode->i_sb->
-							     s_blocksize));
-			/* Search ofor position of new key in the tree. */
-			res =
-			    search_for_position_by_key(inode->i_sb, &key,
-						       &path);
-			if (res == IO_ERROR) {
-				res = -EIO;
-				goto error_exit_free_blocks;
-			}
-			bh = get_last_bh(&path);
-			ih = get_ih(&path);
-			item = get_item(&path);
-			itempos = path.pos_in_item;
-			continue;	// loop to check all kinds of conditions and so on.
-		}
-		/* Ok, we have correct position in item now, so let's see if it is
-		   representing file hole (blocknumber is zero) and fill it if needed */
-		if (!item[itempos]) {
-			/* Ok, a hole. Now we need to check if we already prepared this
-			   block to be journaled */
-			while (!modifying_this_item) {	// loop until succeed
-				/* Well, this item is not journaled yet, so we must prepare
-				   it for journal first, before we can change it */
-				struct item_head tmp_ih;	// We copy item head of found item,
-				// here to detect if fs changed under
-				// us while we were preparing for
-				// journal.
-				int fs_gen;	// We store fs generation here to find if someone
-				// changes fs under our feet
-
-				copy_item_head(&tmp_ih, ih);	// Remember itemhead
-				fs_gen = get_generation(inode->i_sb);	// remember fs generation
-				reiserfs_prepare_for_journal(inode->i_sb, bh, 1);	// Prepare a buffer within which indirect item is stored for changing.
-				if (fs_changed(fs_gen, inode->i_sb)
-				    && item_moved(&tmp_ih, &path)) {
-					// Sigh, fs was changed under us, we need to look for new
-					// location of item we are working with
-
-					/* unmark prepaerd area as journaled and search for it's
-					   new position */
-					reiserfs_restore_prepared_buffer(inode->
-									 i_sb,
-									 bh);
-					res =
-					    search_for_position_by_key(inode->
-								       i_sb,
-								       &key,
-								       &path);
-					if (res == IO_ERROR) {
-						res = -EIO;
-						goto error_exit_free_blocks;
-					}
-					bh = get_last_bh(&path);
-					ih = get_ih(&path);
-					item = get_item(&path);
-					itempos = path.pos_in_item;
-					goto retry;
-				}
-				modifying_this_item = 1;
-			}
-			item[itempos] = allocated_blocks[curr_block];	// Assign new block
-			curr_block++;
-		}
-		itempos++;
-	}
-
-	if (modifying_this_item) {	// We need to log last-accessed block, if it
-		// was modified, but not logged yet.
-		journal_mark_dirty(th, inode->i_sb, bh);
-	}
-
-	if (curr_block < blocks_to_allocate) {
-		// Oh, well need to append to indirect item, or to create indirect item
-		// if there weren't any
-		if (is_indirect_le_ih(ih)) {
-			// Existing indirect item - append. First calculate key for append
-			// position. We do not need to recalculate path as it should
-			// already point to correct place.
-			make_cpu_key(&key, inode,
-				     le_key_k_offset(get_inode_item_key_version
-						     (inode),
-						     &(ih->ih_key)) +
-				     op_bytes_number(ih,
-						     inode->i_sb->s_blocksize),
-				     TYPE_INDIRECT, 3);
-			res =
-			    reiserfs_paste_into_item(th, &path, &key, inode,
-						     (char *)(allocated_blocks +
-							      curr_block),
-						     UNFM_P_SIZE *
-						     (blocks_to_allocate -
-						      curr_block));
-			if (res) {
-				goto error_exit_free_blocks;
-			}
-		} else if (is_statdata_le_ih(ih)) {
-			// Last found item was statdata. That means we need to create indirect item.
-			struct item_head ins_ih;	/* itemhead for new item */
-
-			/* create a key for our new item */
-			make_cpu_key(&key, inode, 1, TYPE_INDIRECT, 3);	// Position one,
-			// because that's
-			// where first
-			// indirect item
-			// begins
-			/* Create new item head for our new item */
-			make_le_item_head(&ins_ih, &key, key.version, 1,
-					  TYPE_INDIRECT,
-					  (blocks_to_allocate -
-					   curr_block) * UNFM_P_SIZE,
-					  0 /* free space */ );
-			/* Find where such item should live in the tree */
-			res = search_item(inode->i_sb, &key, &path);
-			if (res != ITEM_NOT_FOUND) {
-				/* Well, if we have found such item already, or some error
-				   occured, we need to warn user and return error */
-				if (res != -ENOSPC) {
-					reiserfs_warning(inode->i_sb,
-							 "green-9009: search_by_key (%K) "
-							 "returned %d", &key,
-							 res);
-				}
-				res = -EIO;
-				goto error_exit_free_blocks;
-			}
-			/* Insert item into the tree with the data as its body */
-			res =
-			    reiserfs_insert_item(th, &path, &key, &ins_ih,
-						 inode,
-						 (char *)(allocated_blocks +
-							  curr_block));
-		} else {
-			reiserfs_panic(inode->i_sb,
-				       "green-9010: unexpected item type for key %K\n",
-				       &key);
-		}
-	}
-	// the caller is responsible for closing the transaction
-	// unless we return an error, they are also responsible for logging
-	// the inode.
-	//
-	pathrelse(&path);
-	/*
-	 * cleanup prellocation from previous writes
-	 * if this is a partial block write
-	 */
-	if (write_bytes & (inode->i_sb->s_blocksize - 1))
-		reiserfs_discard_prealloc(th, inode);
-	reiserfs_write_unlock(inode->i_sb);
-
-	// go through all the pages/buffers and map the buffers to newly allocated
-	// blocks (so that system knows where to write these pages later).
-	curr_block = 0;
-	for (i = 0; i < num_pages; i++) {
-		struct page *page = prepared_pages[i];	//current page
-		struct buffer_head *head = page_buffers(page);	// first buffer for a page
-		int block_start, block_end;	// in-page offsets for buffers.
-
-		if (!page_buffers(page))
-			reiserfs_panic(inode->i_sb,
-				       "green-9005: No buffers for prepared page???");
-
-		/* For each buffer in page */
-		for (bh = head, block_start = 0; bh != head || !block_start;
-		     block_start = block_end, bh = bh->b_this_page) {
-			if (!bh)
-				reiserfs_panic(inode->i_sb,
-					       "green-9006: Allocated but absent buffer for a page?");
-			block_end = block_start + inode->i_sb->s_blocksize;
-			if (i == 0 && block_end <= from)
-				/* if this buffer is before requested data to map, skip it */
-				continue;
-			if (i == num_pages - 1 && block_start >= to)
-				/* If this buffer is after requested data to map, abort
-				   processing of current page */
-				break;
-
-			if (!buffer_mapped(bh)) {	// Ok, unmapped buffer, need to map it
-				map_bh(bh, inode->i_sb,
-				       le32_to_cpu(allocated_blocks
-						   [curr_block]));
-				curr_block++;
-				set_buffer_new(bh);
-			}
-		}
-	}
-
-	RFALSE(curr_block > blocks_to_allocate,
-	       "green-9007: Used too many blocks? weird");
-
-	kfree(allocated_blocks);
-	return 0;
-
-// Need to deal with transaction here.
-      error_exit_free_blocks:
-	pathrelse(&path);
-	// free blocks
-	for (i = 0; i < blocks_to_allocate; i++)
-		reiserfs_free_block(th, inode, le32_to_cpu(allocated_blocks[i]),
-				    1);
-
-      error_exit:
-	if (th->t_trans_id) {
-		int err;
-		// update any changes we made to blk count
-		mark_inode_dirty(inode);
-		err =
-		    journal_end(th, inode->i_sb,
-				JOURNAL_PER_BALANCE_CNT * 3 + 1 +
-				2 * REISERFS_QUOTA_TRANS_BLOCKS(inode->i_sb));
-		if (err)
-			res = err;
-	}
-	reiserfs_write_unlock(inode->i_sb);
-	kfree(allocated_blocks);
-
-	return res;
-}
-
-/* Unlock pages prepared by reiserfs_prepare_file_region_for_write */
-static void reiserfs_unprepare_pages(struct page **prepared_pages,	/* list of locked pages */
-				     size_t num_pages /* amount of pages */ )
-{
-	int i;			// loop counter
-
-	for (i = 0; i < num_pages; i++) {
-		struct page *page = prepared_pages[i];
-
-		try_to_free_buffers(page);
-		unlock_page(page);
-		page_cache_release(page);
-	}
-}
-
-/* This function will copy data from userspace to specified pages within
-   supplied byte range */
-static int reiserfs_copy_from_user_to_file_region(loff_t pos,	/* In-file position */
-						  int num_pages,	/* Number of pages affected */
-						  int write_bytes,	/* Amount of bytes to write */
-						  struct page **prepared_pages,	/* pointer to 
-										   array to
-										   prepared pages
-										 */
-						  const char __user * buf	/* Pointer to user-supplied
-										   data */
-    )
-{
-	long page_fault = 0;	// status of copy_from_user.
-	int i;			// loop counter.
-	int offset;		// offset in page
-
-	for (i = 0, offset = (pos & (PAGE_CACHE_SIZE - 1)); i < num_pages;
-	     i++, offset = 0) {
-		size_t count = min_t(size_t, PAGE_CACHE_SIZE - offset, write_bytes);	// How much of bytes to write to this page
-		struct page *page = prepared_pages[i];	// Current page we process.
-
-		fault_in_pages_readable(buf, count);
-
-		/* Copy data from userspace to the current page */
-		kmap(page);
-		page_fault = __copy_from_user(page_address(page) + offset, buf, count);	// Copy the data.
-		/* Flush processor's dcache for this page */
-		flush_dcache_page(page);
-		kunmap(page);
-		buf += count;
-		write_bytes -= count;
-
-		if (page_fault)
-			break;	// Was there a fault? abort.
-	}
-
-	return page_fault ? -EFAULT : 0;
-}
-
 /* taken fs/buffer.c:__block_commit_write */
 int reiserfs_commit_page(struct inode *inode, struct page *page,
 			 unsigned from, unsigned to)
@@ -824,432 +222,6 @@ int reiserfs_commit_page(struct inode *inode, struct page *page,
 	return ret;
 }
 
-/* Submit pages for write. This was separated from actual file copying
-   because we might want to allocate block numbers in-between.
-   This function assumes that caller will adjust file size to correct value. */
-static int reiserfs_submit_file_region_for_write(struct reiserfs_transaction_handle *th, struct inode *inode, loff_t pos,	/* Writing position offset */
-						 size_t num_pages,	/* Number of pages to write */
-						 size_t write_bytes,	/* number of bytes to write */
-						 struct page **prepared_pages	/* list of pages */
-    )
-{
-	int status;		// return status of block_commit_write.
-	int retval = 0;		// Return value we are going to return.
-	int i;			// loop counter
-	int offset;		// Writing offset in page.
-	int orig_write_bytes = write_bytes;
-	int sd_update = 0;
-
-	for (i = 0, offset = (pos & (PAGE_CACHE_SIZE - 1)); i < num_pages;
-	     i++, offset = 0) {
-		int count = min_t(int, PAGE_CACHE_SIZE - offset, write_bytes);	// How much of bytes to write to this page
-		struct page *page = prepared_pages[i];	// Current page we process.
-
-		status =
-		    reiserfs_commit_page(inode, page, offset, offset + count);
-		if (status)
-			retval = status;	// To not overcomplicate matters We are going to
-		// submit all the pages even if there was error.
-		// we only remember error status to report it on
-		// exit.
-		write_bytes -= count;
-	}
-	/* now that we've gotten all the ordered buffers marked dirty,
-	 * we can safely update i_size and close any running transaction
-	 */
-	if (pos + orig_write_bytes > inode->i_size) {
-		inode->i_size = pos + orig_write_bytes;	// Set new size
-		/* If the file have grown so much that tail packing is no
-		 * longer possible, reset "need to pack" flag */
-		if ((have_large_tails(inode->i_sb) &&
-		     inode->i_size > i_block_size(inode) * 4) ||
-		    (have_small_tails(inode->i_sb) &&
-		     inode->i_size > i_block_size(inode)))
-			REISERFS_I(inode)->i_flags &= ~i_pack_on_close_mask;
-		else if ((have_large_tails(inode->i_sb) &&
-			  inode->i_size < i_block_size(inode) * 4) ||
-			 (have_small_tails(inode->i_sb) &&
-			  inode->i_size < i_block_size(inode)))
-			REISERFS_I(inode)->i_flags |= i_pack_on_close_mask;
-
-		if (th->t_trans_id) {
-			reiserfs_write_lock(inode->i_sb);
-			// this sets the proper flags for O_SYNC to trigger a commit
-			mark_inode_dirty(inode);
-			reiserfs_write_unlock(inode->i_sb);
-		} else {
-			reiserfs_write_lock(inode->i_sb);
-			reiserfs_update_inode_transaction(inode);
-			mark_inode_dirty(inode);
-			reiserfs_write_unlock(inode->i_sb);
-		}
-
-		sd_update = 1;
-	}
-	if (th->t_trans_id) {
-		reiserfs_write_lock(inode->i_sb);
-		if (!sd_update)
-			mark_inode_dirty(inode);
-		status = journal_end(th, th->t_super, th->t_blocks_allocated);
-		if (status)
-			retval = status;
-		reiserfs_write_unlock(inode->i_sb);
-	}
-	th->t_trans_id = 0;
-
-	/* 
-	 * we have to unlock the pages after updating i_size, otherwise
-	 * we race with writepage
-	 */
-	for (i = 0; i < num_pages; i++) {
-		struct page *page = prepared_pages[i];
-		unlock_page(page);
-		mark_page_accessed(page);
-		page_cache_release(page);
-	}
-	return retval;
-}
-
-/* Look if passed writing region is going to touch file's tail
-   (if it is present). And if it is, convert the tail to unformatted node */
-static int reiserfs_check_for_tail_and_convert(struct inode *inode,	/* inode to deal with */
-					       loff_t pos,	/* Writing position */
-					       int write_bytes	/* amount of bytes to write */
-    )
-{
-	INITIALIZE_PATH(path);	// needed for search_for_position
-	struct cpu_key key;	// Key that would represent last touched writing byte.
-	struct item_head *ih;	// item header of found block;
-	int res;		// Return value of various functions we call.
-	int cont_expand_offset;	// We will put offset for generic_cont_expand here
-	// This can be int just because tails are created
-	// only for small files.
-
-/* this embodies a dependency on a particular tail policy */
-	if (inode->i_size >= inode->i_sb->s_blocksize * 4) {
-		/* such a big files do not have tails, so we won't bother ourselves
-		   to look for tails, simply return */
-		return 0;
-	}
-
-	reiserfs_write_lock(inode->i_sb);
-	/* find the item containing the last byte to be written, or if
-	 * writing past the end of the file then the last item of the
-	 * file (and then we check its type). */
-	make_cpu_key(&key, inode, pos + write_bytes + 1, TYPE_ANY,
-		     3 /*key length */ );
-	res = search_for_position_by_key(inode->i_sb, &key, &path);
-	if (res == IO_ERROR) {
-		reiserfs_write_unlock(inode->i_sb);
-		return -EIO;
-	}
-	ih = get_ih(&path);
-	res = 0;
-	if (is_direct_le_ih(ih)) {
-		/* Ok, closest item is file tail (tails are stored in "direct"
-		 * items), so we need to unpack it. */
-		/* To not overcomplicate matters, we just call generic_cont_expand
-		   which will in turn call other stuff and finally will boil down to
-		   reiserfs_get_block() that would do necessary conversion. */
-		cont_expand_offset =
-		    le_key_k_offset(get_inode_item_key_version(inode),
-				    &(ih->ih_key));
-		pathrelse(&path);
-		res = generic_cont_expand(inode, cont_expand_offset);
-	} else
-		pathrelse(&path);
-
-	reiserfs_write_unlock(inode->i_sb);
-	return res;
-}
-
-/* This function locks pages starting from @pos for @inode.
-   @num_pages pages are locked and stored in
-   @prepared_pages array. Also buffers are allocated for these pages.
-   First and last page of the region is read if it is overwritten only
-   partially. If last page did not exist before write (file hole or file
-   append), it is zeroed, then. 
-   Returns number of unallocated blocks that should be allocated to cover
-   new file data.*/
-static int reiserfs_prepare_file_region_for_write(struct inode *inode
-						  /* Inode of the file */ ,
-						  loff_t pos,	/* position in the file */
-						  size_t num_pages,	/* number of pages to
-									   prepare */
-						  size_t write_bytes,	/* Amount of bytes to be
-									   overwritten from
-									   @pos */
-						  struct page **prepared_pages	/* pointer to array
-										   where to store
-										   prepared pages */
-    )
-{
-	int res = 0;		// Return values of different functions we call.
-	unsigned long index = pos >> PAGE_CACHE_SHIFT;	// Offset in file in pages.
-	int from = (pos & (PAGE_CACHE_SIZE - 1));	// Writing offset in first page
-	int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1;
-	/* offset of last modified byte in last
-	   page */
-	struct address_space *mapping = inode->i_mapping;	// Pages are mapped here.
-	int i;			// Simple counter
-	int blocks = 0;		/* Return value (blocks that should be allocated) */
-	struct buffer_head *bh, *head;	// Current bufferhead and first bufferhead
-	// of a page.
-	unsigned block_start, block_end;	// Starting and ending offsets of current
-	// buffer in the page.
-	struct buffer_head *wait[2], **wait_bh = wait;	// Buffers for page, if
-	// Page appeared to be not up
-	// to date. Note how we have
-	// at most 2 buffers, this is
-	// because we at most may
-	// partially overwrite two
-	// buffers for one page. One at                                                 // the beginning of write area
-	// and one at the end.
-	// Everything inthe middle gets                                                 // overwritten totally.
-
-	struct cpu_key key;	// cpu key of item that we are going to deal with
-	struct item_head *ih = NULL;	// pointer to item head that we are going to deal with
-	struct buffer_head *itembuf = NULL;	// Buffer head that contains items that we are going to deal with
-	INITIALIZE_PATH(path);	// path to item, that we are going to deal with.
-	__le32 *item = NULL;	// pointer to item we are going to deal with
-	int item_pos = -1;	/* Position in indirect item */
-
-	if (num_pages < 1) {
-		reiserfs_warning(inode->i_sb,
-				 "green-9001: reiserfs_prepare_file_region_for_write "
-				 "called with zero number of pages to process");
-		return -EFAULT;
-	}
-
-	/* We have 2 loops for pages. In first loop we grab and lock the pages, so
-	   that nobody would touch these until we release the pages. Then
-	   we'd start to deal with mapping buffers to blocks. */
-	for (i = 0; i < num_pages; i++) {
-		prepared_pages[i] = grab_cache_page(mapping, index + i);	// locks the page
-		if (!prepared_pages[i]) {
-			res = -ENOMEM;
-			goto failed_page_grabbing;
-		}
-		if (!page_has_buffers(prepared_pages[i]))
-			create_empty_buffers(prepared_pages[i],
-					     inode->i_sb->s_blocksize, 0);
-	}
-
-	/* Let's count amount of blocks for a case where all the blocks
-	   overwritten are new (we will substract already allocated blocks later) */
-	if (num_pages > 2)
-		/* These are full-overwritten pages so we count all the blocks in
-		   these pages are counted as needed to be allocated */
-		blocks =
-		    (num_pages - 2) << (PAGE_CACHE_SHIFT - inode->i_blkbits);
-
-	/* count blocks needed for first page (possibly partially written) */
-	blocks += ((PAGE_CACHE_SIZE - from) >> inode->i_blkbits) + !!(from & (inode->i_sb->s_blocksize - 1));	/* roundup */
-
-	/* Now we account for last page. If last page == first page (we
-	   overwrite only one page), we substract all the blocks past the
-	   last writing position in a page out of already calculated number
-	   of blocks */
-	blocks += ((num_pages > 1) << (PAGE_CACHE_SHIFT - inode->i_blkbits)) -
-	    ((PAGE_CACHE_SIZE - to) >> inode->i_blkbits);
-	/* Note how we do not roundup here since partial blocks still
-	   should be allocated */
-
-	/* Now if all the write area lies past the file end, no point in
-	   maping blocks, since there is none, so we just zero out remaining
-	   parts of first and last pages in write area (if needed) */
-	if ((pos & ~((loff_t) PAGE_CACHE_SIZE - 1)) > inode->i_size) {
-		if (from != 0)		/* First page needs to be partially zeroed */
-			zero_user_page(prepared_pages[0], 0, from, KM_USER0);
-
-		if (to != PAGE_CACHE_SIZE)	/* Last page needs to be partially zeroed */
-			zero_user_page(prepared_pages[num_pages-1], to,
-					PAGE_CACHE_SIZE - to, KM_USER0);
-
-		/* Since all blocks are new - use already calculated value */
-		return blocks;
-	}
-
-	/* Well, since we write somewhere into the middle of a file, there is
-	   possibility we are writing over some already allocated blocks, so
-	   let's map these blocks and substract number of such blocks out of blocks
-	   we need to allocate (calculated above) */
-	/* Mask write position to start on blocksize, we do it out of the
-	   loop for performance reasons */
-	pos &= ~((loff_t) inode->i_sb->s_blocksize - 1);
-	/* Set cpu key to the starting position in a file (on left block boundary) */
-	make_cpu_key(&key, inode,
-		     1 + ((pos) & ~((loff_t) inode->i_sb->s_blocksize - 1)),
-		     TYPE_ANY, 3 /*key length */ );
-
-	reiserfs_write_lock(inode->i_sb);	// We need that for at least search_by_key()
-	for (i = 0; i < num_pages; i++) {
-
-		head = page_buffers(prepared_pages[i]);
-		/* For each buffer in the page */
-		for (bh = head, block_start = 0; bh != head || !block_start;
-		     block_start = block_end, bh = bh->b_this_page) {
-			if (!bh)
-				reiserfs_panic(inode->i_sb,
-					       "green-9002: Allocated but absent buffer for a page?");
-			/* Find where this buffer ends */
-			block_end = block_start + inode->i_sb->s_blocksize;
-			if (i == 0 && block_end <= from)
-				/* if this buffer is before requested data to map, skip it */
-				continue;
-
-			if (i == num_pages - 1 && block_start >= to) {
-				/* If this buffer is after requested data to map, abort
-				   processing of current page */
-				break;
-			}
-
-			if (buffer_mapped(bh) && bh->b_blocknr != 0) {
-				/* This is optimisation for a case where buffer is mapped
-				   and have blocknumber assigned. In case significant amount
-				   of such buffers are present, we may avoid some amount
-				   of search_by_key calls.
-				   Probably it would be possible to move parts of this code
-				   out of BKL, but I afraid that would overcomplicate code
-				   without any noticeable benefit.
-				 */
-				item_pos++;
-				/* Update the key */
-				set_cpu_key_k_offset(&key,
-						     cpu_key_k_offset(&key) +
-						     inode->i_sb->s_blocksize);
-				blocks--;	// Decrease the amount of blocks that need to be
-				// allocated
-				continue;	// Go to the next buffer
-			}
-
-			if (!itembuf ||	/* if first iteration */
-			    item_pos >= ih_item_len(ih) / UNFM_P_SIZE) {	/* or if we progressed past the
-										   current unformatted_item */
-				/* Try to find next item */
-				res =
-				    search_for_position_by_key(inode->i_sb,
-							       &key, &path);
-				/* Abort if no more items */
-				if (res != POSITION_FOUND) {
-					/* make sure later loops don't use this item */
-					itembuf = NULL;
-					item = NULL;
-					break;
-				}
-
-				/* Update information about current indirect item */
-				itembuf = get_last_bh(&path);
-				ih = get_ih(&path);
-				item = get_item(&path);
-				item_pos = path.pos_in_item;
-
-				RFALSE(!is_indirect_le_ih(ih),
-				       "green-9003: indirect item expected");
-			}
-
-			/* See if there is some block associated with the file
-			   at that position, map the buffer to this block */
-			if (get_block_num(item, item_pos)) {
-				map_bh(bh, inode->i_sb,
-				       get_block_num(item, item_pos));
-				blocks--;	// Decrease the amount of blocks that need to be
-				// allocated
-			}
-			item_pos++;
-			/* Update the key */
-			set_cpu_key_k_offset(&key,
-					     cpu_key_k_offset(&key) +
-					     inode->i_sb->s_blocksize);
-		}
-	}
-	pathrelse(&path);	// Free the path
-	reiserfs_write_unlock(inode->i_sb);
-
-	/* Now zero out unmappend buffers for the first and last pages of
-	   write area or issue read requests if page is mapped. */
-	/* First page, see if it is not uptodate */
-	if (!PageUptodate(prepared_pages[0])) {
-		head = page_buffers(prepared_pages[0]);
-
-		/* For each buffer in page */
-		for (bh = head, block_start = 0; bh != head || !block_start;
-		     block_start = block_end, bh = bh->b_this_page) {
-
-			if (!bh)
-				reiserfs_panic(inode->i_sb,
-					       "green-9002: Allocated but absent buffer for a page?");
-			/* Find where this buffer ends */
-			block_end = block_start + inode->i_sb->s_blocksize;
-			if (block_end <= from)
-				/* if this buffer is before requested data to map, skip it */
-				continue;
-			if (block_start < from) {	/* Aha, our partial buffer */
-				if (buffer_mapped(bh)) {	/* If it is mapped, we need to
-								   issue READ request for it to
-								   not loose data */
-					ll_rw_block(READ, 1, &bh);
-					*wait_bh++ = bh;
-				} else {	/* Not mapped, zero it */
-					zero_user_page(prepared_pages[0],
-						       block_start,
-						       from - block_start, KM_USER0);
-					set_buffer_uptodate(bh);
-				}
-			}
-		}
-	}
-
-	/* Last page, see if it is not uptodate, or if the last page is past the end of the file. */
-	if (!PageUptodate(prepared_pages[num_pages - 1]) ||
-	    ((pos + write_bytes) >> PAGE_CACHE_SHIFT) >
-	    (inode->i_size >> PAGE_CACHE_SHIFT)) {
-		head = page_buffers(prepared_pages[num_pages - 1]);
-
-		/* for each buffer in page */
-		for (bh = head, block_start = 0; bh != head || !block_start;
-		     block_start = block_end, bh = bh->b_this_page) {
-
-			if (!bh)
-				reiserfs_panic(inode->i_sb,
-					       "green-9002: Allocated but absent buffer for a page?");
-			/* Find where this buffer ends */
-			block_end = block_start + inode->i_sb->s_blocksize;
-			if (block_start >= to)
-				/* if this buffer is after requested data to map, skip it */
-				break;
-			if (block_end > to) {	/* Aha, our partial buffer */
-				if (buffer_mapped(bh)) {	/* If it is mapped, we need to
-								   issue READ request for it to
-								   not loose data */
-					ll_rw_block(READ, 1, &bh);
-					*wait_bh++ = bh;
-				} else {	/* Not mapped, zero it */
-					zero_user_page(prepared_pages[num_pages-1],
-							to, block_end - to, KM_USER0);
-					set_buffer_uptodate(bh);
-				}
-			}
-		}
-	}
-
-	/* Wait for read requests we made to happen, if necessary */
-	while (wait_bh > wait) {
-		wait_on_buffer(*--wait_bh);
-		if (!buffer_uptodate(*wait_bh)) {
-			res = -EIO;
-			goto failed_read;
-		}
-	}
-
-	return blocks;
-      failed_page_grabbing:
-	num_pages = i;
-      failed_read:
-	reiserfs_unprepare_pages(prepared_pages, num_pages);
-	return res;
-}
-
 /* Write @count bytes at position @ppos in a file indicated by @file
    from the buffer @buf.  
 
@@ -1284,14 +256,9 @@ static ssize_t reiserfs_file_write(struct file *file,	/* the file we are going t
 							 * new current position before returning. */
 				   )
 {
-	size_t already_written = 0;	// Number of bytes already written to the file.
-	loff_t pos;		// Current position in the file.
-	ssize_t res;		// return value of various functions that we call.
-	int err = 0;
 	struct inode *inode = file->f_path.dentry->d_inode;	// Inode of the file that we are writing to.
 	/* To simplify coding at this time, we store
 	   locked pages in array for now */
-	struct page *prepared_pages[REISERFS_WRITE_PAGES_AT_A_TIME];
 	struct reiserfs_transaction_handle th;
 	th.t_trans_id = 0;
 
@@ -1311,212 +278,7 @@ static ssize_t reiserfs_file_write(struct file *file,	/* the file we are going t
 			count = MAX_NON_LFS - (unsigned long)*ppos;
 	}
 
-	if (file->f_flags & O_DIRECT)
-		return do_sync_write(file, buf, count, ppos);
-
-	if (unlikely((ssize_t) count < 0))
-		return -EINVAL;
-
-	if (unlikely(!access_ok(VERIFY_READ, buf, count)))
-		return -EFAULT;
-
-	mutex_lock(&inode->i_mutex);	// locks the entire file for just us
-
-	pos = *ppos;
-
-	/* Check if we can write to specified region of file, file
-	   is not overly big and this kind of stuff. Adjust pos and
-	   count, if needed */
-	res = generic_write_checks(file, &pos, &count, 0);
-	if (res)
-		goto out;
-
-	if (count == 0)
-		goto out;
-
-	res = remove_suid(file->f_path.dentry);
-	if (res)
-		goto out;
-
-	file_update_time(file);
-
-	// Ok, we are done with all the checks.
-
-	// Now we should start real work
-
-	/* If we are going to write past the file's packed tail or if we are going
-	   to overwrite part of the tail, we need that tail to be converted into
-	   unformatted node */
-	res = reiserfs_check_for_tail_and_convert(inode, pos, count);
-	if (res)
-		goto out;
-
-	while (count > 0) {
-		/* This is the main loop in which we running until some error occures
-		   or until we write all of the data. */
-		size_t num_pages;	/* amount of pages we are going to write this iteration */
-		size_t write_bytes;	/* amount of bytes to write during this iteration */
-		size_t blocks_to_allocate;	/* how much blocks we need to allocate for this iteration */
-
-		/*  (pos & (PAGE_CACHE_SIZE-1)) is an idiom for offset into a page of pos */
-		num_pages = !!((pos + count) & (PAGE_CACHE_SIZE - 1)) +	/* round up partial
-									   pages */
-		    ((count +
-		      (pos & (PAGE_CACHE_SIZE - 1))) >> PAGE_CACHE_SHIFT);
-		/* convert size to amount of
-		   pages */
-		reiserfs_write_lock(inode->i_sb);
-		if (num_pages > REISERFS_WRITE_PAGES_AT_A_TIME
-		    || num_pages > reiserfs_can_fit_pages(inode->i_sb)) {
-			/* If we were asked to write more data than we want to or if there
-			   is not that much space, then we shorten amount of data to write
-			   for this iteration. */
-			num_pages =
-			    min_t(size_t, REISERFS_WRITE_PAGES_AT_A_TIME,
-				  reiserfs_can_fit_pages(inode->i_sb));
-			/* Also we should not forget to set size in bytes accordingly */
-			write_bytes = (num_pages << PAGE_CACHE_SHIFT) -
-			    (pos & (PAGE_CACHE_SIZE - 1));
-			/* If position is not on the
-			   start of the page, we need
-			   to substract the offset
-			   within page */
-		} else
-			write_bytes = count;
-
-		/* reserve the blocks to be allocated later, so that later on
-		   we still have the space to write the blocks to */
-		reiserfs_claim_blocks_to_be_allocated(inode->i_sb,
-						      num_pages <<
-						      (PAGE_CACHE_SHIFT -
-						       inode->i_blkbits));
-		reiserfs_write_unlock(inode->i_sb);
-
-		if (!num_pages) {	/* If we do not have enough space even for a single page... */
-			if (pos >
-			    inode->i_size + inode->i_sb->s_blocksize -
-			    (pos & (inode->i_sb->s_blocksize - 1))) {
-				res = -ENOSPC;
-				break;	// In case we are writing past the end of the last file block, break.
-			}
-			// Otherwise we are possibly overwriting the file, so
-			// let's set write size to be equal or less than blocksize.
-			// This way we get it correctly for file holes.
-			// But overwriting files on absolutelly full volumes would not
-			// be very efficient. Well, people are not supposed to fill
-			// 100% of disk space anyway.
-			write_bytes =
-			    min_t(size_t, count,
-				  inode->i_sb->s_blocksize -
-				  (pos & (inode->i_sb->s_blocksize - 1)));
-			num_pages = 1;
-			// No blocks were claimed before, so do it now.
-			reiserfs_claim_blocks_to_be_allocated(inode->i_sb,
-							      1 <<
-							      (PAGE_CACHE_SHIFT
-							       -
-							       inode->
-							       i_blkbits));
-		}
-
-		/* Prepare for writing into the region, read in all the
-		   partially overwritten pages, if needed. And lock the pages,
-		   so that nobody else can access these until we are done.
-		   We get number of actual blocks needed as a result. */
-		res = reiserfs_prepare_file_region_for_write(inode, pos,
-							     num_pages,
-							     write_bytes,
-							     prepared_pages);
-		if (res < 0) {
-			reiserfs_release_claimed_blocks(inode->i_sb,
-							num_pages <<
-							(PAGE_CACHE_SHIFT -
-							 inode->i_blkbits));
-			break;
-		}
-
-		blocks_to_allocate = res;
-
-		/* First we correct our estimate of how many blocks we need */
-		reiserfs_release_claimed_blocks(inode->i_sb,
-						(num_pages <<
-						 (PAGE_CACHE_SHIFT -
-						  inode->i_sb->
-						  s_blocksize_bits)) -
-						blocks_to_allocate);
-
-		if (blocks_to_allocate > 0) {	/*We only allocate blocks if we need to */
-			/* Fill in all the possible holes and append the file if needed */
-			res =
-			    reiserfs_allocate_blocks_for_region(&th, inode, pos,
-								num_pages,
-								write_bytes,
-								prepared_pages,
-								blocks_to_allocate);
-		}
-
-		/* well, we have allocated the blocks, so it is time to free
-		   the reservation we made earlier. */
-		reiserfs_release_claimed_blocks(inode->i_sb,
-						blocks_to_allocate);
-		if (res) {
-			reiserfs_unprepare_pages(prepared_pages, num_pages);
-			break;
-		}
-
-/* NOTE that allocating blocks and filling blocks can be done in reverse order
-   and probably we would do that just to get rid of garbage in files after a
-   crash */
-
-		/* Copy data from user-supplied buffer to file's pages */
-		res =
-		    reiserfs_copy_from_user_to_file_region(pos, num_pages,
-							   write_bytes,
-							   prepared_pages, buf);
-		if (res) {
-			reiserfs_unprepare_pages(prepared_pages, num_pages);
-			break;
-		}
-
-		/* Send the pages to disk and unlock them. */
-		res =
-		    reiserfs_submit_file_region_for_write(&th, inode, pos,
-							  num_pages,
-							  write_bytes,
-							  prepared_pages);
-		if (res)
-			break;
-
-		already_written += write_bytes;
-		buf += write_bytes;
-		*ppos = pos += write_bytes;
-		count -= write_bytes;
-		balance_dirty_pages_ratelimited_nr(inode->i_mapping, num_pages);
-	}
-
-	/* this is only true on error */
-	if (th.t_trans_id) {
-		reiserfs_write_lock(inode->i_sb);
-		err = journal_end(&th, th.t_super, th.t_blocks_allocated);
-		reiserfs_write_unlock(inode->i_sb);
-		if (err) {
-			res = err;
-			goto out;
-		}
-	}
-
-	if (likely(res >= 0) &&
-	    (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))))
-		res = generic_osync_inode(inode, file->f_mapping,
-		                          OSYNC_METADATA | OSYNC_DATA);
-
-	mutex_unlock(&inode->i_mutex);
-	reiserfs_async_progress_wait(inode->i_sb);
-	return (already_written != 0) ? already_written : res;
-
-      out:
-	mutex_unlock(&inode->i_mutex);	// unlock the file on exit.
-	return res;
+	return do_sync_write(file, buf, count, ppos);
 }
 
 const struct file_operations reiserfs_file_operations = {