.github/CONTRIBUTING.md

   1 # Contributing to ZFS on Linux
   2 <p align="center"><img src="http://zfsonlinux.org/images/zfs-linux.png"/></p>
   3
   4 *First of all, thank you for taking the time to contribute!*
   5
   6 By using the following guidelines, you can help us make ZFS on Linux even
   7 better.
   8
   9 ## Table Of Contents
  10 [What should I know before I get
  11 started?](#what-should-i-know-before-i-get-started)
  12
  13   * [Get ZFS](#get-zfs)
  14   * [Debug ZFS](#debug-zfs)
  15   * [Where can I ask for help?](#where-can-I-ask-for-help)
  16
  17 [How Can I Contribute?](#how-can-i-contribute)
  18
  19   * [Reporting Bugs](#reporting-bugs)
  20   * [Suggesting Enhancements](#suggesting-enhancements)
  21   * [Pull Requests](#pull-requests)
  22   * [Testing](#testing)
  23
  24 [Style Guides](#style-guides)
  25
  26   * [Coding Conventions](#coding-conventions)
  27   * [Commit Message Formats](#commit-message-formats)
  28     * [New Changes](#new-changes)
  29     * [OpenZFS Patch Ports](#openzfs-patch-ports)
  30     * [Coverity Defect Fixes](#coverity-defect-fixes)
  31     * [Signed Off By](#signed-off-by)
  32
  33 Helpful resources
  34
  35   * [ZFS on Linux wiki](https://github.com/zfsonlinux/zfs/wiki)
  36   * [OpenZFS Documentation](http://open-zfs.org/wiki/Developer_resources)
  37   * [Git and GitHub for beginners](https://github.com/zfsonlinux/zfs/wiki/Git-and-GitHub-for-beginners)
  38
  39 ## What should I know before I get started?
  40
  41 ### Get ZFS
  42 You can build zfs packages by following [these
  43 instructions](https://github.com/zfsonlinux/zfs/wiki/Building-ZFS),
  44 or install stable packages from [your distribution's
  45 repository](https://github.com/zfsonlinux/zfs/wiki/Getting-Started).
  46
  47 ### Debug ZFS
  48 A variety of methods and tools are available to aid ZFS developers.
  49 It's strongly recommended that when developing a patch the `--enable-debug`
  50 configure option should be set. This will enable additional correctness
  51 checks and all the ASSERTs to help quickly catch potential issues.
  52
  53 In addition, there are numerous utilities and debugging files which
  54 provide visibility in to the inner workings of ZFS.  The most useful
  55 of these tools are discussed in detail on the [debugging ZFS wiki
  56 page](https://github.com/zfsonlinux/zfs/wiki/Debugging).
  57
  58 ### Where can I ask for help?
  59 The [mailing list](https://github.com/zfsonlinux/zfs/wiki/Mailing-Lists)
  60 is the best place to ask for help.
  61
  62 ## How Can I Contribute?
  63
  64 ### Reporting Bugs
  65 *Please* contact us via the [mailing
  66 list](https://github.com/zfsonlinux/zfs/wiki/Mailing-Lists) if you aren't
  67 certain that you are experiencing a bug.
  68
  69 If you run into an issue, please search our [issue
  70 tracker](https://github.com/zfsonlinux/zfs/issues) *first* to ensure the
  71 issue hasn't been reported before. Open a new issue only if you haven't
  72 found anything similar to your issue.
  73
  74 You can open a new issue and search existing issues using the public [issue
  75 tracker](https://github.com/zfsonlinux/zfs/issues).
  76
  77 #### When opening a new issue, please include the following information at the top of the issue:
  78 * What distribution (with version) you are using.
  79 * The spl and zfs versions you are using, installation method (repository
  80 or manual compilation).
  81 * Describe the issue you are experiencing.
  82 * Describe how to reproduce the issue.
  83 * Including any warning/errors/backtraces from the system logs.
  84
  85 When a new issue is opened, it is not uncommon for developers to request
  86 additional information.
  87
  88 In general, the more detail you share about a problem the quicker a
  89 developer can resolve it. For example, providing a simple test case is always
  90 exceptionally helpful.
  91
  92 Be prepared to work with the developers investigating your issue. Your
  93 assistance is crucial in providing a quick solution. They may ask for
  94 information like:
  95
  96 * Your pool configuration as reported by `zdb` or `zpool status`.
  97 * Your hardware configuration, such as
  98   * Number of CPUs.
  99   * Amount of memory.
 100   * Whether your system has ECC memory.
 101   * Whether it is running under a VMM/Hypervisor.
 102   * Kernel version.
 103   * Values of the spl/zfs module parameters.
 104 * Stack traces which may be logged to `dmesg`.
 105
 106 ### Suggesting Enhancements
 107 ZFS on Linux is a widely deployed production filesystem which is under
 108 active development. The team's primary focus is on fixing known issues,
 109 improving performance, and adding compelling new features.
 110
 111 You can view the list of proposed features
 112 by filtering the issue tracker by the ["Feature"
 113 label](https://github.com/zfsonlinux/zfs/issues?q=is%3Aopen+is%3Aissue+label%3AFeature).
 114 If you have an idea for a feature first check this list. If your idea already
 115 appears then add a +1 to the top most comment, this helps us gauge interest
 116 in that feature.
 117
 118 Otherwise, open a new issue and describe your proposed feature.  Why is this
 119 feature needed?  What problem does it solve?
 120
 121 ### Pull Requests
 122 * All pull requests must be based on the current master branch and apply
 123 without conflicts.
 124 * Please attempt to limit pull requests to a single commit which resolves
 125 one specific issue.
 126 * Make sure your commit messages are in the correct format. See the
 127 [Commit Message Formats](#commit-message-formats) section for more information.
 128 * When updating a pull request squash multiple commits by performing a
 129 [rebase](https://git-scm.com/docs/git-rebase) (squash).
 130 * For large pull requests consider structuring your changes as a stack of
 131 logically independent patches which build on each other.  This makes large
 132 changes easier to review and approve which speeds up the merging process.
 133 * Try to keep pull requests simple. Simple code with comments is much easier
 134 to review and approve.
 135 * Test cases should be provided when appropriate.
 136 * If your pull request improves performance, please include some benchmarks.
 137 * The pull request must pass all required [ZFS
 138 Buildbot](http://build.zfsonlinux.org/) builders before
 139 being accepted. If you are experiencing intermittent TEST
 140 builder failures, you may be experiencing a [test suite
 141 issue](https://github.com/zfsonlinux/zfs/issues?q=is%3Aissue+is%3Aopen+label%3A%22Test+Suite%22).
 142 There are also various [buildbot options](https://github.com/zfsonlinux/zfs/wiki/Buildbot-Options)
 143 to control how changes are tested.
 144 * All proposed changes must be approved by a ZFS on Linux organization member.
 145
 146 ### Testing
 147 All help is appreciated! If you're in a position to run the latest code
 148 consider helping us by reporting any functional problems, performance
 149 regressions or other suspected issues. By running the latest code to a wide
 150 range of realistic workloads, configurations and architectures we're better
 151 able quickly identify and resolve potential issues.
 152
 153 Users can also run the [ZFS Test
 154 Suite](https://github.com/zfsonlinux/zfs/tree/master/tests) on their systems
 155 to verify ZFS is behaving as intended.
 156
 157 ## Style Guides
 158
 159 ### Coding Conventions
 160 We currently use [C  Style  and  Coding  Standards  for
 161 SunOS](http://www.cis.upenn.edu/%7Elee/06cse480/data/cstyle.ms.pdf) as our
 162 coding convention.
 163
 164 ### Commit Message Formats
 165 #### New Changes
 166 Commit messages for new changes must meet the following guidelines:
 167 * In 72 characters or less, provide a summary of the change as the
 168 first line in the commit message.
 169 * A body which provides a description of the change. If necessary,
 170 please summarize important information such as why the proposed
 171 approach was chosen or a brief description of the bug you are resolving.
 172 Each line of the body must be 72 characters or less.
 173 * The last line must be a `Signed-off-by:` tag. See the
 174 [Signed Off By](#signed-off-by) section for more information.
 175
 176 An example commit message for new changes is provided below.
 177
 178 ```
 179 This line is a brief summary of your change
 180
 181 Please provide at least a couple sentences describing the
 182 change. If necessary, please summarize decisions such as
 183 why the proposed approach was chosen or what bug you are
 184 attempting to solve.
 185
 186 Signed-off-by: Contributor <contributor@email.com>
 187 ```
 188
 189 #### OpenZFS Patch Ports
 190 If you are porting OpenZFS patches, the commit message must meet
 191 the following guidelines:
 192 * The first line must be the summary line from the most important OpenZFS commit being ported.
 193 It must begin with `OpenZFS dddd, dddd - ` where `dddd` are OpenZFS issue numbers.
 194 * Provides a `Authored by:` line to attribute each patch for each original author.
 195 * Provides the `Reviewed by:` and `Approved by:` lines from each original
 196 OpenZFS commit.
 197 * Provides a `Ported-by:` line with the developer's name followed by
 198 their email for each OpenZFS commit.
 199 * Provides a `OpenZFS-issue:` line with link for each original illumos
 200 issue.
 201 * Provides a `OpenZFS-commit:` line with link for each original OpenZFS commit.
 202 * If necessary, provide some porting notes to describe any deviations from
 203 the original OpenZFS commits.
 204
 205 An example OpenZFS patch port commit message for a single patch is provided
 206 below.
 207 ```
 208 OpenZFS 1234 - Summary from the original OpenZFS commit
 209
 210 Authored by: Original Author <original@email.com>
 211 Reviewed by: Reviewer One <reviewer1@email.com>
 212 Reviewed by: Reviewer Two <reviewer2@email.com>
 213 Approved by: Approver One <approver1@email.com>
 214 Ported-by: ZFS Contributor <contributor@email.com>
 215
 216 Provide some porting notes here if necessary.
 217
 218 OpenZFS-issue: https://www.illumos.org/issues/1234
 219 OpenZFS-commit: https://github.com/openzfs/openzfs/commit/abcd1234
 220 ```
 221
 222 If necessary, multiple OpenZFS patches can be combined in a single port.
 223 This is useful when you are porting a new patch and its subsequent bug
 224 fixes. An example commit message is provided below.
 225 ```
 226 OpenZFS 1234, 5678 - Summary of most important OpenZFS commit
 227
 228 1234 Summary from original OpenZFS commit for 1234
 229
 230 Authored by: Original Author <original@email.com>
 231 Reviewed by: Reviewer Two <reviewer2@email.com>
 232 Approved by: Approver One <approver1@email.com>
 233 Ported-by: ZFS Contributor <contributor@email.com>
 234
 235 Provide some porting notes here for 1234 if necessary.
 236
 237 OpenZFS-issue: https://www.illumos.org/issues/1234
 238 OpenZFS-commit: https://github.com/openzfs/openzfs/commit/abcd1234
 239
 240 5678 Summary from original OpenZFS commit for 5678
 241
 242 Authored by: Original Author2 <original2@email.com>
 243 Reviewed by: Reviewer One <reviewer1@email.com>
 244 Approved by: Approver Two <approver2@email.com>
 245 Ported-by: ZFS Contributor <contributor@email.com>
 246
 247 Provide some porting notes here for 5678 if necessary.
 248
 249 OpenZFS-issue: https://www.illumos.org/issues/5678
 250 OpenZFS-commit: https://github.com/openzfs/openzfs/commit/efgh5678
 251 ```
 252
 253 #### Coverity Defect Fixes
 254 If you are submitting a fix to a
 255 [Coverity defect](https://scan.coverity.com/projects/zfsonlinux-zfs),
 256 the commit message should meet the following guidelines:
 257 * Provides a subject line in the format of
 258 `Fix coverity defects: CID dddd, dddd...` where `dddd` represents
 259 each CID fixed by the commit.
 260 * Provides a body which lists each Coverity defect and how it was corrected.
 261 * The last line must be a `Signed-off-by:` tag. See the
 262 [Signed Off By](#signed-off-by) section for more information.
 263
 264 An example Coverity defect fix commit message is provided below.
 265 ```
 266 Fix coverity defects: CID 12345, 67890
 267
 268 CID 12345: Logically dead code (DEADCODE)
 269
 270 Removed the if(var != 0) block because the condition could never be
 271 satisfied.
 272
 273 CID 67890: Resource Leak (RESOURCE_LEAK)
 274
 275 Ensure free is called after allocating memory in function().
 276
 277 Signed-off-by: Contributor <contributor@email.com>
 278 ```
 279
 280 #### Signed Off By
 281 A line tagged as `Signed-off-by:` must contain the developer's
 282 name followed by their email. This is the developer's certification
 283 that they have the right to submit the patch for inclusion into
 284 the code base and indicates agreement to the [Developer's Certificate
 285 of Origin](https://www.kernel.org/doc/html/latest/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin).
 286 Code without a proper signoff cannot be merged.
 287
 288 Git can append the `Signed-off-by` line to your commit messages. Simply
 289 provide the `-s` or `--signoff` option when performing a `git commit`.
 290 For more information about writing commit messages, visit [How to Write
 291 a Git Commit Message](https://chris.beams.io/posts/git-commit/).