ext4: allow DAX writeback for hole punch

Currently when doing a DAX hole punch with ext4 we fail to do a writeback.
This is because the logic around filemap_write_and_wait_range() in
ext4_punch_hole() only looks for dirty page cache pages in the radix tree,
not for dirty DAX exceptional entries.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Ross Zwisler 2016-09-22 11:49:38 -04:00 committed by Theodore Ts'o
parent e03a9976af
commit cca32b7eeb

View file

@ -3892,7 +3892,7 @@ int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset,
} }
/* /*
* ext4_punch_hole: punches a hole in a file by releaseing the blocks * ext4_punch_hole: punches a hole in a file by releasing the blocks
* associated with the given offset and length * associated with the given offset and length
* *
* @inode: File inode * @inode: File inode
@ -3921,7 +3921,7 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
* Write out all dirty pages to avoid race conditions * Write out all dirty pages to avoid race conditions
* Then release them. * Then release them.
*/ */
if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) { if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
ret = filemap_write_and_wait_range(mapping, offset, ret = filemap_write_and_wait_range(mapping, offset,
offset + length - 1); offset + length - 1);
if (ret) if (ret)