4.9-stable review patch. If anyone has any objections, please let me know.
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From: Lukas Czerner lczerner@redhat.com
commit eee597ac931305eff3d3fd1d61d6aae553bc0984 upstream.
Currently in ext4_punch_hole we're going to skip the mtime update if there are no actual blocks to release. However we've actually modified the file by zeroing the partial block so the mtime should be updated.
Moreover the sync and datasync handling is skipped as well, which is also wrong. Fix it.
Signed-off-by: Lukas Czerner lczerner@redhat.com Signed-off-by: Theodore Ts'o tytso@mit.edu Reported-by: Joe Habermann joe.habermann@quantum.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/ext4/inode.c | 40 ++++++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 20 deletions(-)
--- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4038,28 +4038,28 @@ int ext4_punch_hole(struct inode *inode, EXT4_BLOCK_SIZE_BITS(sb); stop_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
- /* If there are no blocks to remove, return now */ - if (first_block >= stop_block) - goto out_stop; - - down_write(&EXT4_I(inode)->i_data_sem); - ext4_discard_preallocations(inode); - - ret = ext4_es_remove_extent(inode, first_block, - stop_block - first_block); - if (ret) { - up_write(&EXT4_I(inode)->i_data_sem); - goto out_stop; - } + /* If there are blocks to remove, do it */ + if (stop_block > first_block) { + + down_write(&EXT4_I(inode)->i_data_sem); + ext4_discard_preallocations(inode);
- if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) - ret = ext4_ext_remove_space(inode, first_block, - stop_block - 1); - else - ret = ext4_ind_remove_space(handle, inode, first_block, - stop_block); + ret = ext4_es_remove_extent(inode, first_block, + stop_block - first_block); + if (ret) { + up_write(&EXT4_I(inode)->i_data_sem); + goto out_stop; + } + + if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) + ret = ext4_ext_remove_space(inode, first_block, + stop_block - 1); + else + ret = ext4_ind_remove_space(handle, inode, first_block, + stop_block);
- up_write(&EXT4_I(inode)->i_data_sem); + up_write(&EXT4_I(inode)->i_data_sem); + } if (IS_SYNC(inode)) ext4_handle_sync(handle);