Skip to content

Commit

Permalink
Merge pull request #1228 from kolyshkin/bind-mount
Browse files Browse the repository at this point in the history
config: improve bind mount and propagation doc
  • Loading branch information
tianon authored Sep 22, 2023
2 parents 989e575 + 2f6b090 commit c0e9043
Showing 1 changed file with 13 additions and 11 deletions.
24 changes: 13 additions & 11 deletions config.md
Original file line number Diff line number Diff line change
Expand Up @@ -94,7 +94,7 @@ Runtimes MUST/SHOULD/MAY implement the following option strings for Linux:
------------------|-------------|-----------------------------------------------------
`async` | MUST | [^1]
`atime` | MUST | [^1]
`bind` | MUST | [^2] (bind mounts)
`bind` | MUST | Bind mount [^2]
`defaults` | MUST | [^1]
`dev` | MUST | [^1]
`diratime` | MUST | [^1]
Expand All @@ -115,9 +115,9 @@ Runtimes MUST/SHOULD/MAY implement the following option strings for Linux:
`nostrictatime` | MUST | [^1]
`nosuid` | MUST | [^1]
`nosymfollow` | SHOULD | [^1] (Introduced in kernel 5.10, util-linux 2.38)
`private` | MUST | [^2] (bind mounts)
`private` | MUST | Bind mount propagation [^2]
`ratime` | SHOULD | Recursive `atime` [^3]
`rbind` | MUST | [^2] (bind mounts)
`rbind` | MUST | Recursive bind mount [^2]
`rdev` | SHOULD | Recursive `dev` [^3]
`rdiratime` | SHOULD | Recursive `diratime` [^3]
`relatime` | MUST | [^1]
Expand All @@ -131,39 +131,40 @@ Runtimes MUST/SHOULD/MAY implement the following option strings for Linux:
`rnosuid` | SHOULD | Recursive `nosuid` [^3]
`rnosymfollow` | SHOULD | Recursive `nosymfollow` [^3]
`ro` | MUST | [^1]
`rprivate` | MUST | [^2] (bind mounts)
`rprivate` | MUST | Bind mount propagation [^2]
`rrelatime ` | SHOULD | Recursive `relatime` [^3]
`rro` | SHOULD | Recursive `ro` [^3]
`rrw` | SHOULD | Recursive `rw` [^3]
`rshared` | MUST | [^2] (bind mounts)
`rslave` | MUST | [^2] (bind mounts)
`rshared` | MUST | Bind mount propagation [^2]
`rslave` | MUST | Bind mount propagation [^2]
`rstrictatime` | SHOULD | Recursive `strictatime` [^3]
`rsuid` | SHOULD | Recursive `suid` [^3]
`rsymfollow` | SHOULD | Recursive `symfollow` [^3]
`runbindable` | MUST | [^2] (bind mounts)
`runbindable` | MUST | Bind mount propagation [^2]
`rw` | MUST | [^1]
`shared` | MUST | [^1]
`silent` | MUST | [^1]
`slave` | MUST | [^2] (bind mounts)
`slave` | MUST | Bind mount propagation [^2]
`strictatime` | MUST | [^1]
`suid` | MUST | [^1]
`symfollow` | SHOULD | Opposite of `nosymfollow`
`sync` | MUST | [^1]
`tmpcopyup` | MAY | copy up the contents to a tmpfs
`unbindable` | MUST | [^2] (bind mounts)
`unbindable` | MUST | Bind mount propagation [^2]
`idmap` | SHOULD | Indicates that the mount has `uidMappings` and `gidMappings` specified. This option SHOULD NOT be passed to the underlying [`mount(2)`][mount.2] call. If supported, the runtime MUST return an error if this option is provided and either of `uidMappings` or `gidMappings` are empty or not present.
`ridmap` | SHOULD | Indicates that the mount has `uidMappings` and `gidMappings` specified, and the mapping is applied recursively [^3]. This option SHOULD NOT be passed to the underlying [`mount(2)`][mount.2] call. If supported, the runtime MUST return an error if this option is provided and either of `uidMappings` or `gidMappings` are empty or not present.

[^1]: Corresponds to [`mount(8)` (filesystem-independent)][mount.8-filesystem-independent].
[^2]: Corresponds to [`mount(8)` (filesystem-specific)][mount.8-filesystem-specific].
[^2]: Corresponds to [bind mounts and shared subtrees][mount-bind].
[^3]: These `AT_RECURSIVE` options need kernel 5.12 or later. See [`mount_setattr(2)`][mount_setattr.2]

The "MUST" options correspond to [`mount(8)`][mount.8].

Runtimes MAY also implement custom option strings that are not listed in the table above.
If a custom option string is already recognized by [`mount(8)`][mount.8], the runtime SHOULD follow the behavior of [`mount(8)`][mount.8].

Runtimes SHOULD pass unknown options to [`mount(2)`][mount.2] via the fifth argument (`const void *data`).
Runtimes SHOULD treat unknown options as [filesystem-specific ones][mount.8-filesystem-specific])
and pass those as a comma-separated string to the fifth (`const void *data`) argument of [`mount(2)`][mount.2].

### Example (Windows)

Expand Down Expand Up @@ -1135,6 +1136,7 @@ Here is a full example `config.json` for reference.
[mount.8-filesystem-independent]: http://man7.org/linux/man-pages/man8/mount.8.html#FILESYSTEM-INDEPENDENT_MOUNT_OPTIONS
[mount.8-filesystem-specific]: http://man7.org/linux/man-pages/man8/mount.8.html#FILESYSTEM-SPECIFIC_MOUNT_OPTIONS
[mount_setattr.2]: http://man7.org/linux/man-pages/man2/mount_setattr.2.html
[mount-bind]: https://docs.kernel.org/filesystems/sharedsubtree.html
[getrlimit.2]: http://man7.org/linux/man-pages/man2/getrlimit.2.html
[getrlimit.3]: http://pubs.opengroup.org/onlinepubs/9699919799/functions/getrlimit.html
[stdin.3]: http://man7.org/linux/man-pages/man3/stdin.3.html
Expand Down

0 comments on commit c0e9043

Please sign in to comment.