Describe supported metadata types, add step-by-step patch sending instruction, mention minimally supported kernel version and licensing. Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@xxxxxxxxxxxxxxx> --- README.md | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 README.md diff --git a/README.md b/README.md new file mode 100644 index 000000000000..64f2ecec784e --- /dev/null +++ b/README.md @@ -0,0 +1,83 @@ +**mdadm** is a utility used to create and manage **software RAID** devices implemented through +**Multiple devices driver (MD)** in kernel. It supports following RAID metadata formats: + +* [Linux native RAID](https://raid.wiki.kernel.org/index.php/RAID_superblock_formats): + + Known as **native** or **native RAID**. First and default metadata format. Metadata management + is implemented in **MD driver**. + +* Matrix Storage Manager Support (no reference, metadata format documentation is proprietary). + + Known as **IMSM**. Metadata format developed and maintained by **Intel®** as a part of **VROC** + solution. There are some functional differences between **native** and **imsm**. The most + important difference is that the metadata is managed from userspace. + + **CAUTION:** **imsm** is compatible with **Intel RST**, however it is not officially supported. + You are using it on your own risk. + +* [Common RAID DDF Specification Revision](https://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf) + + **IMPORTANT:** DDF is in **maintenance only** mode. There is no active development around it. + Please do not use it in new solutions. + +# How to Contribute + + **mdadm** is hosted on [kernel.org](https://kernel.org/). You can access repository +[here](https://git.kernel.org/pub/scm/utils/mdadm/mdadm.git). + +It is maintained similarly to kernel, using *mailing list*. Patches must be send through email. +Please familiarize with general kernel +[submitting patches](https://www.kernel.org/doc/html/v4.17/process/submitting-patches.html) +documentation. Formatting, tags and commit message guidelines applies to **mdadm**. + +## Sending patches step-by-step + +To maximize change of patches being taken, follow this instruction when submitting: + +1. Create possibly logically separated commits and generate patches: + + Use ``git format-patch --cover-letter --signoff -v <nr>`` to create patches: + * ``--cover-letter`` can be skipped if it is only one patch; + * ``--signoff`` adds sign-off tag; + * ``-v <nr>`` indicates review revision number, sender should increment it before resending. + +2. Check style of every patch with kernel + [checkpatch](https://docs.kernel.org/dev-tools/checkpatch.html) script: + + It is important to keep same coding style that is why in **mdadm** + [kernel coding style](https://www.kernel.org/doc/html/v4.10/process/coding-style.html) + is preferred. ``checkpath --no-tree <patch_file>`` can be used to verify patches. + Following checkpatch issues can be ignored: + - New typedefs. + - comparing with *True/False*. + - kernel *MAINTAINERS* file warning. + - *extern* keyword in headers. + +3. Send patches using ``git send-mail --to=linux-raid@xxxxxxxxxxxxxxx <cover-letter> <patch1> <patch2> (...)`` + +# Maintainers + +It is good practice to add **mdadm maintainers** to recipients for patches: + +- Jes Sorensen <jes@xxxxxxxxxxxxxxxxxx>; +- Mariusz Tkaczyk <mariusz.tkaczyk@xxxxxxxxxxxxxxx>; + +Adding **MD maintainers** could be reasonable, especially if patches may affect MD driver: + +- Song Liu <song@xxxxxxxxxx>; +- Yu Kuai <yukuai3@xxxxxxxxxx>; + +# Reviewers + +**mdadm** utility is not part of kernel tree, so there is no certificated *Reviewers* list. Everyone +can comment on mailing list, last decision (and merging) belongs to maintainers. + +# Minimal supported kernel version + +We do not support kernel versions below **v3.10**. Please be aware that maintainers may remove +workarounds and fixes for legacy issues. + +# License + +It is released under the terms of the **GNU General Public License version 2** as published +by the **Free Software Foundation**. -- 2.35.3
