[PATCH] ext3: small fix for previous retries patch in ext3_prepare_write()

[Kirill Korotaev <dev@openvz.org>]

Patch from Dmitry Monakhov:
Previous fix for retries in ext3_prepare_write() violation
was a bit errorneuos:
- it missed return of error code from ext3_journal_stop()
- it missed do_journal_get_write_access() before commit_write

a few comments added also.

Signed-Off-By: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-Off-By: Kirill Korotaev <dev@openvz.org>


diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index a48ada9..1acb528 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1162,13 +1162,14 @@ static int ext3_prepare_failure(struct f
 	struct buffer_head *bh, *head, *next;
 	unsigned block_start, block_end;
 	unsigned blocksize;
+	int ret;
+	handle_t *handle = ext3_journal_current_handle();
 
 	mapping = page->mapping;
 	if (ext3_should_writeback_data(mapping->host)) {
 		/* optimization: no constraints about data */
 skip:
-		ext3_journal_stop(ext3_journal_current_handle());
-		return 0;
+		return ext3_journal_stop(handle);
 	}
 
 	head = page_buffers(page);
@@ -1186,7 +1187,19 @@ skip:
 			break;
 		}
 		if (!buffer_mapped(bh))
+		/* prepare_write failed on this bh */
 			break;
+		if (ext3_should_journal_data(mapping->host)) {
+			ret = do_journal_get_write_access(handle, bh);
+			if (ret) {
+				ext3_journal_stop(handle);
+				return ret;
+			}
+		}
+	/*
+	 * block_start here becomes the first block where the current iteration
+	 * of prepare_write failed.
+	 */
 	}
 	if (block_start <= from)
 		goto skip;