freebsd man page for vfs_busy

VFS_BUSY(9)						   BSD Kernel Developer's Manual					       VFS_BUSY(9)

NAME
     vfs_busy -- marks a mount point as busy

SYNOPSIS
     #include <sys/param.h>
     #include <sys/mount.h>

     int
     vfs_busy(struct mount *mp, int flags);

DESCRIPTION
     The vfs_busy() function marks a mount point as busy by incrementing the reference count of a mount point.	It also delays unmounting by
     sleeping on mp if the MNTK_UNMOUNT flag is set in mp->mnt_kern_flag and the MBF_NOWAIT flag is not set.

     Its arguments are:

     mp     The mount point to busy.

     flags  Flags controlling how vfs_busy() should act.

	    MBF_NOWAIT	    do not sleep if MNTK_UNMOUNT is set.

	    MBF_MNTLSTLOCK  drop the mountlist_mtx in the critical path.

RETURN VALUES
     A 0 value is returned on success.	If the mount point is being unmounted and MBF_NOWAIT flag is specified ENOENT will be returned.

ERRORS
     [ENOENT]		The mount point is being unmounted (MNTK_UNMOUNT is set).

SEE ALSO
     vfs_unbusy(9)

AUTHORS
     This manual page was written by Chad David <davidc@acns.ab.ca>.

BSD
								 February 11, 2013							       BSD