forked from mirrors/linux
		
	autofs: update struct autofs_dev_ioctl in Documentation
Sync with changes made by commit 730c9eeca9 ("autofs4: improve
parameter usage") which introduced an union for various ioctl commands
instead of having statically named arg1,2.
This commit simply replaces arg1,2 with the corresponding fields without
changing semantics.
Link: http://lkml.kernel.org/r/20160812024831.12352.24667.stgit@pluto.themaw.net
Signed-off-by: Tomohiro Kusumi <kusumi.tomohiro@gmail.com>
Signed-off-by: Ian Kent <ikent@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
			
			
This commit is contained in:
		
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					 1 changed files with 42 additions and 28 deletions
				
			
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			@ -179,8 +179,19 @@ struct autofs_dev_ioctl {
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				 * including this struct */
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	__s32 ioctlfd;          /* automount command fd */
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	__u32 arg1;             /* Command parameters */
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	__u32 arg2;
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	union {
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		struct args_protover		protover;
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		struct args_protosubver		protosubver;
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		struct args_openmount		openmount;
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		struct args_ready		ready;
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		struct args_fail		fail;
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		struct args_setpipefd		setpipefd;
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		struct args_timeout		timeout;
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		struct args_requester		requester;
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		struct args_expire		expire;
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		struct args_askumount		askumount;
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		struct args_ismountpoint	ismountpoint;
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	};
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	char path[0];
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};
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			@ -192,8 +203,8 @@ optionally be used to check a specific mount corresponding to a given
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mount point file descriptor, and when requesting the uid and gid of the
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last successful mount on a directory within the autofs file system.
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The fields arg1 and arg2 are used to communicate parameters and results of
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calls made as described below.
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The union is used to communicate parameters and results of calls made
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as described below.
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The path field is used to pass a path where it is needed and the size field
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is used account for the increased structure length when translating the
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			@ -245,9 +256,9 @@ AUTOFS_DEV_IOCTL_PROTOVER_CMD and AUTOFS_DEV_IOCTL_PROTOSUBVER_CMD
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Get the major and minor version of the autofs4 protocol version understood
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by loaded module. This call requires an initialized struct autofs_dev_ioctl
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with the ioctlfd field set to a valid autofs mount point descriptor
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and sets the requested version number in structure field arg1. These
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commands return 0 on success or one of the negative error codes if
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validation fails.
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and sets the requested version number in version field of struct args_protover
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or sub_version field of struct args_protosubver. These commands return
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0 on success or one of the negative error codes if validation fails.
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AUTOFS_DEV_IOCTL_OPENMOUNT and AUTOFS_DEV_IOCTL_CLOSEMOUNT
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			@ -256,9 +267,9 @@ AUTOFS_DEV_IOCTL_OPENMOUNT and AUTOFS_DEV_IOCTL_CLOSEMOUNT
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Obtain and release a file descriptor for an autofs managed mount point
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path. The open call requires an initialized struct autofs_dev_ioctl with
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the path field set and the size field adjusted appropriately as well
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as the arg1 field set to the device number of the autofs mount. The
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device number can be obtained from the mount options shown in
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/proc/mounts. The close call requires an initialized struct
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as the devid field of struct args_openmount set to the device number of
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the autofs mount. The device number can be obtained from the mount options
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shown in /proc/mounts. The close call requires an initialized struct
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autofs_dev_ioct with the ioctlfd field set to the descriptor obtained
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from the open call. The release of the file descriptor can also be done
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with close(2) so any open descriptors will also be closed at process exit.
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			@ -272,10 +283,10 @@ AUTOFS_DEV_IOCTL_READY_CMD and AUTOFS_DEV_IOCTL_FAIL_CMD
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Return mount and expire result status from user space to the kernel.
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Both of these calls require an initialized struct autofs_dev_ioctl
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with the ioctlfd field set to the descriptor obtained from the open
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call and the arg1 field set to the wait queue token number, received
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by user space in the foregoing mount or expire request. The arg2 field
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is set to the status to be returned. For the ready call this is always
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0 and for the fail call it is set to the errno of the operation.
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call and the token field of struct args_ready or struct args_fail set
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to the wait queue token number, received by user space in the foregoing
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mount or expire request. The status field of struct args_fail is set to
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the errno of the operation. It is set to 0 on success.
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AUTOFS_DEV_IOCTL_SETPIPEFD_CMD
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			@ -290,9 +301,10 @@ mount be catatonic (see next call).
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The call requires an initialized struct autofs_dev_ioctl with the
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ioctlfd field set to the descriptor obtained from the open call and
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the arg1 field set to descriptor of the pipe. On success the call
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also sets the process group id used to identify the controlling process
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(eg. the owning automount(8) daemon) to the process group of the caller.
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the pipefd field of struct args_setpipefd set to descriptor of the pipe.
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On success the call also sets the process group id used to identify the
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controlling process (eg. the owning automount(8) daemon) to the process
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group of the caller.
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AUTOFS_DEV_IOCTL_CATATONIC_CMD
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			@ -323,8 +335,8 @@ mount on the given path dentry.
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The call requires an initialized struct autofs_dev_ioctl with the path
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field set to the mount point in question and the size field adjusted
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appropriately. Upon return the struct field arg1 contains the uid and
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arg2 the gid.
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appropriately. Upon return the uid field of struct args_requester contains
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the uid and gid field the gid.
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When reconstructing an autofs mount tree with active mounts we need to
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re-connect to mounts that may have used the original process uid and
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			@ -342,8 +354,9 @@ this ioctl is called until no further expire candidates are found.
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The call requires an initialized struct autofs_dev_ioctl with the
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ioctlfd field set to the descriptor obtained from the open call. In
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addition an immediate expire, independent of the mount timeout, can be
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requested by setting the arg1 field to 1. If no expire candidates can
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be found the ioctl returns -1 with errno set to EAGAIN.
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requested by setting the how field of struct args_expire to 1. If no
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expire candidates can be found the ioctl returns -1 with errno set to
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EAGAIN.
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This call causes the kernel module to check the mount corresponding
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to the given ioctlfd for mounts that can be expired, issues an expire
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			@ -356,7 +369,8 @@ Checks if an autofs mount point is in use.
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The call requires an initialized struct autofs_dev_ioctl with the
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ioctlfd field set to the descriptor obtained from the open call and
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it returns the result in the arg1 field, 1 for busy and 0 otherwise.
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it returns the result in the may_umount field of struct args_askumount,
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1 for busy and 0 otherwise.
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AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD
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			@ -368,12 +382,12 @@ The call requires an initialized struct autofs_dev_ioctl. There are two
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possible variations. Both use the path field set to the path of the mount
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point to check and the size field adjusted appropriately. One uses the
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ioctlfd field to identify a specific mount point to check while the other
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variation uses the path and optionally arg1 set to an autofs mount type.
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The call returns 1 if this is a mount point and sets arg1 to the device
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number of the mount and field arg2 to the relevant super block magic
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number (described below) or 0 if it isn't a mountpoint. In both cases
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the the device number (as returned by new_encode_dev()) is returned
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in field arg1.
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variation uses the path and optionally in.type field of struct args_ismountpoint
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set to an autofs mount type. The call returns 1 if this is a mount point
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and sets out.devid field to the device number of the mount and out.magic
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field to the relevant super block magic number (described below) or 0 if
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it isn't a mountpoint. In both cases the the device number (as returned
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by new_encode_dev()) is returned in out.devid field.
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If supplied with a file descriptor we're looking for a specific mount,
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not necessarily at the top of the mounted stack. In this case the path
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