1 files changed, 74 insertions, 65 deletions

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 4a09ff1..d3ef656 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1149,12 +1149,15 @@ static int ext3_write_begin(struct file *file, struct address_space *mapping,
 				struct page **pagep, void **fsdata)
 {
 	struct inode *inode = mapping->host;
-	int ret, needed_blocks = ext3_writepage_trans_blocks(inode);
+	int ret;
 	handle_t *handle;
 	int retries = 0;
 	struct page *page;
 	pgoff_t index;
 	unsigned from, to;
+	/* Reserve one block more for addition to orphan list in case
+	 * we allocate blocks but write fails for some reason */
+	int needed_blocks = ext3_writepage_trans_blocks(inode) + 1;
 
 	index = pos >> PAGE_CACHE_SHIFT;
 	from = pos & (PAGE_CACHE_SIZE - 1);
@@ -1184,15 +1187,20 @@ retry:
 	}
 write_begin_failed:
 	if (ret) {
-		ext3_journal_stop(handle);
-		unlock_page(page);
-		page_cache_release(page);
 		/*
 		 * block_write_begin may have instantiated a few blocks
 		 * outside i_size.  Trim these off again. Don't need
 		 * i_size_read because we hold i_mutex.
+		 *
+		 * Add inode to orphan list in case we crash before truncate
+		 * finishes.
 		 */
 		if (pos + len > inode->i_size)
+			ext3_orphan_add(handle, inode);
+		ext3_journal_stop(handle);
+		unlock_page(page);
+		page_cache_release(page);
+		if (pos + len > inode->i_size)
 			vmtruncate(inode, inode->i_size);
 	}
 	if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
@@ -1211,6 +1219,18 @@ int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
 	return err;
 }
 
+/* For ordered writepage and write_end functions */
+static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
+{
+	/*
+	 * Write could have mapped the buffer but it didn't copy the data in
+	 * yet. So avoid filing such buffer into a transaction.
+	 */
+	if (buffer_mapped(bh) && buffer_uptodate(bh))
+		return ext3_journal_dirty_data(handle, bh);
+	return 0;
+}
+
 /* For write_end() in data=journal mode */
 static int write_end_fn(handle_t *handle, struct buffer_head *bh)
 {
@@ -1221,26 +1241,20 @@ static int write_end_fn(handle_t *handle, struct buffer_head *bh)
 }
 
 /*
- * Generic write_end handler for ordered and writeback ext3 journal modes.
- * We can't use generic_write_end, because that unlocks the page and we need to
- * unlock the page after ext3_journal_stop, but ext3_journal_stop must run
- * after block_write_end.
+ * This is nasty and subtle: ext3_write_begin() could have allocated blocks
+ * for the whole page but later we failed to copy the data in. Update inode
+ * size according to what we managed to copy. The rest is going to be
+ * truncated in write_end function.
  */
-static int ext3_generic_write_end(struct file *file,
-				struct address_space *mapping,
-				loff_t pos, unsigned len, unsigned copied,
-				struct page *page, void *fsdata)
+static void update_file_sizes(struct inode *inode, loff_t pos, unsigned copied)
 {
-	struct inode *inode = file->f_mapping->host;
-
-	copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
-
-	if (pos+copied > inode->i_size) {
-		i_size_write(inode, pos+copied);
+	/* What matters to us is i_disksize. We don't write i_size anywhere */
+	if (pos + copied > inode->i_size)
+		i_size_write(inode, pos + copied);
+	if (pos + copied > EXT3_I(inode)->i_disksize) {
+		EXT3_I(inode)->i_disksize = pos + copied;
 		mark_inode_dirty(inode);
 	}
-
-	return copied;
 }
 
 /*
@@ -1260,35 +1274,29 @@ static int ext3_ordered_write_end(struct file *file,
 	unsigned from, to;
 	int ret = 0, ret2;
 
-	from = pos & (PAGE_CACHE_SIZE - 1);
-	to = from + len;
+	copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
 
+	from = pos & (PAGE_CACHE_SIZE - 1);
+	to = from + copied;
 	ret = walk_page_buffers(handle, page_buffers(page),
-		from, to, NULL, ext3_journal_dirty_data);
+		from, to, NULL, journal_dirty_data_fn);
 
-	if (ret == 0) {
-		/*
-		 * generic_write_end() will run mark_inode_dirty() if i_size
-		 * changes.  So let's piggyback the i_disksize mark_inode_dirty
-		 * into that.
-		 */
-		loff_t new_i_size;
-
-		new_i_size = pos + copied;
-		if (new_i_size > EXT3_I(inode)->i_disksize)
-			EXT3_I(inode)->i_disksize = new_i_size;
-		ret2 = ext3_generic_write_end(file, mapping, pos, len, copied,
-							page, fsdata);
-		copied = ret2;
-		if (ret2 < 0)
-			ret = ret2;
-	}
+	if (ret == 0)
+		update_file_sizes(inode, pos, copied);
+	/*
+	 * There may be allocated blocks outside of i_size because
+	 * we failed to copy some data. Prepare for truncate.
+	 */
+	if (pos + len > inode->i_size)
+		ext3_orphan_add(handle, inode);
 	ret2 = ext3_journal_stop(handle);
 	if (!ret)
 		ret = ret2;
 	unlock_page(page);
 	page_cache_release(page);
 
+	if (pos + len > inode->i_size)
+		vmtruncate(inode, inode->i_size);
 	return ret ? ret : copied;
 }
 
@@ -1299,25 +1307,22 @@ static int ext3_writeback_write_end(struct file *file,
 {
 	handle_t *handle = ext3_journal_current_handle();
 	struct inode *inode = file->f_mapping->host;
-	int ret = 0, ret2;
-	loff_t new_i_size;
-
-	new_i_size = pos + copied;
-	if (new_i_size > EXT3_I(inode)->i_disksize)
-		EXT3_I(inode)->i_disksize = new_i_size;
-
-	ret2 = ext3_generic_write_end(file, mapping, pos, len, copied,
-							page, fsdata);
-	copied = ret2;
-	if (ret2 < 0)
-		ret = ret2;
+	int ret;
 
-	ret2 = ext3_journal_stop(handle);
-	if (!ret)
-		ret = ret2;
+	copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
+	update_file_sizes(inode, pos, copied);
+	/*
+	 * There may be allocated blocks outside of i_size because
+	 * we failed to copy some data. Prepare for truncate.
+	 */
+	if (pos + len > inode->i_size)
+		ext3_orphan_add(handle, inode);
+	ret = ext3_journal_stop(handle);
 	unlock_page(page);
 	page_cache_release(page);
 
+	if (pos + len > inode->i_size)
+		vmtruncate(inode, inode->i_size);
 	return ret ? ret : copied;
 }
 
@@ -1338,15 +1343,23 @@ static int ext3_journalled_write_end(struct file *file,
 	if (copied < len) {
 		if (!PageUptodate(page))
 			copied = 0;
-		page_zero_new_buffers(page, from+copied, to);
+		page_zero_new_buffers(page, from + copied, to);
+		to = from + copied;
 	}
 
 	ret = walk_page_buffers(handle, page_buffers(page), from,
 				to, &partial, write_end_fn);
 	if (!partial)
 		SetPageUptodate(page);
-	if (pos+copied > inode->i_size)
-		i_size_write(inode, pos+copied);
+
+	if (pos + copied > inode->i_size)
+		i_size_write(inode, pos + copied);
+	/*
+	 * There may be allocated blocks outside of i_size because
+	 * we failed to copy some data. Prepare for truncate.
+	 */
+	if (pos + len > inode->i_size)
+		ext3_orphan_add(handle, inode);
 	EXT3_I(inode)->i_state |= EXT3_STATE_JDATA;
 	if (inode->i_size > EXT3_I(inode)->i_disksize) {
 		EXT3_I(inode)->i_disksize = inode->i_size;
@@ -1361,6 +1374,8 @@ static int ext3_journalled_write_end(struct file *file,
 	unlock_page(page);
 	page_cache_release(page);
 
+	if (pos + len > inode->i_size)
+		vmtruncate(inode, inode->i_size);
 	return ret ? ret : copied;
 }
 
@@ -1428,17 +1443,11 @@ static int bput_one(handle_t *handle, struct buffer_head *bh)
 	return 0;
 }
 
-static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
-{
-	if (buffer_mapped(bh))
-		return ext3_journal_dirty_data(handle, bh);
-	return 0;
-}
-
 static int buffer_unmapped(handle_t *handle, struct buffer_head *bh)
 {
 	return !buffer_mapped(bh);
 }
+
 /*
  * Note that we always start a transaction even if we're not journalling
  * data.  This is to preserve ordering: any hole instantiation within