Commit 9b6cd5f7 authored May 16, 2016 by Jan Kara Committed by Vishal Verma May 17, 2016

ext2: Fix block zeroing in ext2_get_blocks() for DAX



When zeroing allocated blocks for DAX, we accidentally zeroed only the
first allocated block instead of all of them. So far this problem is
hidden by the fact that page faults always need only a single block and
DAX write code zeroes blocks again. But the zeroing in DAX code is racy
and needs to be removed so fix the zeroing in ext2 to zero all allocated
blocks.

Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>

parent 02fbd139

fs/ext2/inode.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -740,7 +740,7 @@ static int ext2_get_blocks(struct inode *inode,
		err = dax_clear_sectors(inode->i_sb->s_bdev,
		le32_to_cpu(chain[depth-1].key) <<
		(inode->i_blkbits - 9),
		1 << inode->i_blkbits);
		count << inode->i_blkbits);
		if (err) {
		mutex_unlock(&ei->truncate_mutex);
		goto cleanup;

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