debian man page for vfs_unlock_giant

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

NAME
     VFS_LOCK_GIANT, VFS_UNLOCK_GIANT -- conditionally lock and unlock Giant around entry into VFS

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

     int
     VFS_LOCK_GIANT(struct mount *mp);

     void
     VFS_UNLOCK_GIANT(int vfslocked);

DESCRIPTION
     VFS_LOCK_GIANT() will conditionally acquire the Giant lock if the file system referenced by mp is marked as MPSAFE or not, returning a flag
     indicating whether Giant was set, which may later be passed to VFS_UNLOCK_GIANT().  The value of mp will typically be derived from the mount
     pointer in a vnode on which a VFS operation will be performed.

     VFS_UNLOCK_GIANT() conditionally releases the Giant lock if the passed vfslocked argument is non-zero.  It is expected that the argument will
     be derived from the return values of VFS_LOCK_GIANT() or NDHASGIANT(9).

RETURN VALUES
     VFS_LOCK_GIANT() returns a boolean indicating whether or not Giant was acquired.

SEE ALSO
     mutex(9), NDHASGIANT(9), vnode(9)

AUTHORS
     MPSAFE VFS support for FreeBSD was implemented by Jeff Roberson.

     This manual page was written by Robert Watson.

BUGS
     Non-MPSAFE file systems exist, requiring callers conditional locking and unlocking of Giant.

BSD
								September 21, 2005							       BSD