diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/autofs-mount-control.rst (renamed from Documentation/filesystems/autofs-mount-control.txt) | 108 | ||||
| -rw-r--r-- | Documentation/filesystems/index.rst | 1 |
2 files changed, 56 insertions, 53 deletions
diff --git a/Documentation/filesystems/autofs-mount-control.txt b/Documentation/filesystems/autofs-mount-control.rst index acc02fc579938..2903aed923161 100644 --- a/Documentation/filesystems/autofs-mount-control.txt +++ b/Documentation/filesystems/autofs-mount-control.rst @@ -1,4 +1,6 @@ +.. SPDX-License-Identifier: GPL-2.0 +==================================================================== Miscellaneous Device control operations for the autofs kernel module ==================================================================== @@ -36,24 +38,24 @@ For example, there are two types of automount maps, direct (in the kernel module source you will see a third type called an offset, which is just a direct mount in disguise) and indirect. -Here is a master map with direct and indirect map entries: +Here is a master map with direct and indirect map entries:: -/- /etc/auto.direct -/test /etc/auto.indirect + /- /etc/auto.direct + /test /etc/auto.indirect -and the corresponding map files: +and the corresponding map files:: -/etc/auto.direct: + /etc/auto.direct: -/automount/dparse/g6 budgie:/autofs/export1 -/automount/dparse/g1 shark:/autofs/export1 -and so on. + /automount/dparse/g6 budgie:/autofs/export1 + /automount/dparse/g1 shark:/autofs/export1 + and so on. -/etc/auto.indirect: +/etc/auto.indirect:: -g1 shark:/autofs/export1 -g6 budgie:/autofs/export1 -and so on. + g1 shark:/autofs/export1 + g6 budgie:/autofs/export1 + and so on. For the above indirect map an autofs file system is mounted on /test and mounts are triggered for each sub-directory key by the inode lookup @@ -69,23 +71,23 @@ use the follow_link inode operation to trigger the mount. But, each entry in direct and indirect maps can have offsets (making them multi-mount map entries). -For example, an indirect mount map entry could also be: +For example, an indirect mount map entry could also be:: -g1 \ - / shark:/autofs/export5/testing/test \ - /s1 shark:/autofs/export/testing/test/s1 \ - /s2 shark:/autofs/export5/testing/test/s2 \ - /s1/ss1 shark:/autofs/export1 \ - /s2/ss2 shark:/autofs/export2 + g1 \ + / shark:/autofs/export5/testing/test \ + /s1 shark:/autofs/export/testing/test/s1 \ + /s2 shark:/autofs/export5/testing/test/s2 \ + /s1/ss1 shark:/autofs/export1 \ + /s2/ss2 shark:/autofs/export2 -and a similarly a direct mount map entry could also be: +and a similarly a direct mount map entry could also be:: -/automount/dparse/g1 \ - / shark:/autofs/export5/testing/test \ - /s1 shark:/autofs/export/testing/test/s1 \ - /s2 shark:/autofs/export5/testing/test/s2 \ - /s1/ss1 shark:/autofs/export2 \ - /s2/ss2 shark:/autofs/export2 + /automount/dparse/g1 \ + / shark:/autofs/export5/testing/test \ + /s1 shark:/autofs/export/testing/test/s1 \ + /s2 shark:/autofs/export5/testing/test/s2 \ + /s1/ss1 shark:/autofs/export2 \ + /s2/ss2 shark:/autofs/export2 One of the issues with version 4 of autofs was that, when mounting an entry with a large number of offsets, possibly with nesting, we needed @@ -170,32 +172,32 @@ autofs Miscellaneous Device mount control interface The control interface is opening a device node, typically /dev/autofs. All the ioctls use a common structure to pass the needed parameter -information and return operation results: - -struct autofs_dev_ioctl { - __u32 ver_major; - __u32 ver_minor; - __u32 size; /* total size of data passed in - * including this struct */ - __s32 ioctlfd; /* automount command fd */ - - /* Command parameters */ - union { - struct args_protover protover; - struct args_protosubver protosubver; - struct args_openmount openmount; - struct args_ready ready; - struct args_fail fail; - struct args_setpipefd setpipefd; - struct args_timeout timeout; - struct args_requester requester; - struct args_expire expire; - struct args_askumount askumount; - struct args_ismountpoint ismountpoint; - }; - - char path[0]; -}; +information and return operation results:: + + struct autofs_dev_ioctl { + __u32 ver_major; + __u32 ver_minor; + __u32 size; /* total size of data passed in + * including this struct */ + __s32 ioctlfd; /* automount command fd */ + + /* Command parameters */ + union { + struct args_protover protover; + struct args_protosubver protosubver; + struct args_openmount openmount; + struct args_ready ready; + struct args_fail fail; + struct args_setpipefd setpipefd; + struct args_timeout timeout; + struct args_requester requester; + struct args_expire expire; + struct args_askumount askumount; + struct args_ismountpoint ismountpoint; + }; + + char path[0]; + }; The ioctlfd field is a mount point file descriptor of an autofs mount point. It is returned by the open call and is used by all calls except @@ -212,7 +214,7 @@ is used account for the increased structure length when translating the structure sent from user space. This structure can be initialized before setting specific fields by using -the void function call init_autofs_dev_ioctl(struct autofs_dev_ioctl *). +the void function call init_autofs_dev_ioctl(``struct autofs_dev_ioctl *``). All of the ioctls perform a copy of this structure from user space to kernel space and return -EINVAL if the size parameter is smaller than diff --git a/Documentation/filesystems/index.rst b/Documentation/filesystems/index.rst index 0598bc52abdc8..c9480138d47e4 100644 --- a/Documentation/filesystems/index.rst +++ b/Documentation/filesystems/index.rst @@ -51,6 +51,7 @@ Documentation for filesystem implementations. affs afs autofs + autofs-mount-control fuse overlayfs virtiofs |