[PATCH v4 13/20] Revert "ext4: fix fsx truncate failure"

Lukas Czerner
2013-05-14T16:37:27Z

This reverts commit 189e868fa8fdca702eb9db9d8afc46b5cb9144c9.

This commit reintroduces the use of ext4_block_truncate_page() in ext4
truncate operation instead of ext4_discard_partial_page_buffers().

The statement in the commit description that the truncate operation only
zero block unaligned portion of the last page is not exactly right,
since truncate_pagecache_range() also zeroes and invalidate the unaligned
portion of the page. Then there is no need to zero and unmap it once more
and ext4_block_truncate_page() was doing the right job, although we
still need to update the buffer head containing the last block, which is
exactly what ext4_block_truncate_page() is doing.

Moreover the problem described in the commit is fixed more properly with
commit

15291164b22a357cb211b618adfef4fa82fc0de3
jbd2: clear BH_Delay & BH_Unwritten in journal_unmap_buffer

This was tested on ppc64 machine with block size of 1024 bytes without
any problems.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
fs/ext4/inode.c | 11 ++---------
1 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 8187c3e..34ebb62 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3937,7 +3937,6 @@ void ext4_truncate(struct inode *inode)
unsigned int credits;
handle_t *handle;
struct address_space *mapping = inode->i_mapping;
- loff_t page_len;

/*
* There is a possibility that we're either freeing the inode
@@ -3981,14 +3980,8 @@ void ext4_truncate(struct inode *inode)
return;
}

- if (inode->i_size % PAGE_CACHE_SIZE != 0) {
- page_len = PAGE_CACHE_SIZE -
- (inode->i_size & (PAGE_CACHE_SIZE - 1));
-
- if (ext4_discard_partial_page_buffers(handle,
- mapping, inode->i_size, page_len, 0))
- goto out_stop;
- }
+ if (inode->i_size & (inode->i_sb->s_blocksize - 1))
+ ext4_block_truncate_page(handle, mapping, inode->i_size);

/*
* We add the inode to the orphan list, so that if this