Konstantin Komarov, founder and CEO of Paragon Software, on the Linux kernel mailing list with a full implementation of the file system , which supports work in read and write mode. The code is open under the GPL license.
The implementation supports all the features of the current version of NTFS 3.1, including extended file attributes, data compression mode, effective work with voids in files, and playback of changes from the log to restore integrity after failures. The proposed driver currently uses its own truncated implementation of the NTFS journal, but in the future it is planned to add support for full journaling on top of the universal block device available in the kernel (Journaling block device), on the basis of which journaling is organized in ext3, ext4 and OCFS2.
The driver is based on the code base of an existing commercial Paragon Software and well tested. The patches are designed in accordance with the requirements for preparing code for Linux and do not contain bindings to additional APIs, which allows you to include the new driver in the main kernel. Once patches are included in the core Linux kernel, Paragon Software intends to maintain them, fix bugs, and extend functionality.
However, inclusion in the kernel may take time due to the need for third-party reviews of the proposed code. The comments to the post also mention with assembly and number of for patch design. For example, it is proposed to split the sent patch into parts, since 27 thousand lines in one patch is too much and creates difficulties in reviewing and checking. In the MAINTAINERS file, it is recommended to explicitly define the policy for further maintenance of the code and specify the Git branch to which patches should be sent. It also notes the need to negotiate the addition of a new NTFS implementation when there is an old fs/ntfs driver that runs in read-only mode.
Previously, to fully access NTFS partitions from Linux, you had to use the NTFS-3g FUSE driver, which runs in user space and does not provide the desired performance. This driver since 2017, as well as the read-only fs/ntfs driver. Both drivers were created by Tuxera, which, like Paragon Software, proprietary NTFS driver distributed commercially.
Recall that in October last year, after Microsoft's public specifications and the free use of exFAT patents on Linux, Paragon Software has open-sourced its driver with an implementation of the exFAT FS. The first version of the driver was limited to read-only operation, but a write-enabled version was in development. These patches remained unclaimed and the exFAT driver was adopted into the core of the kernel, Samsung and used in the firmware of Android smartphones of this company. This move was painful. at Paragon Software, which with criticism of open implementations of exFAT and NTFS.
Source: opennet.ru