TAKE - fix some inode teardown issues

[Steve Lord <lord@sgi.com>]

This fixes some issues between creating new inodes and tearing
down old ones, freezing and thawing a filesystem seemed to be a
good way of exposing this . It is a definite improvement over the
old code, 36 hours continuous stress testing and still going vs 
about 10 minutes for the old code. Not convinced this is a totally
closed issue yet though.

Date:  Sun Sep  1 05:43:34 PDT 2002
Workarea:  jen.americas.sgi.com:/src/lord/xfs-linux.2.4

The following file(s) were checked into:
  bonnie.engr.sgi.com:/isms/slinx/2.4.x-xfs


Modid:  2.4.x-xfs:slinx:126536a
linux/fs/xfs/xfs_vnodeops.c - 1.560
	- fix a hole between sync and reclaim, clean up finish_reclaim code,
	  add comments

linux/fs/xfs/xfs_vfsops.c - 1.377
	- pass flush mode into xfs_finish_reclaim instead of a flag

linux/fs/xfs/xfs_iget.c - 1.169
	- deal with the case where we race between looking up and tearing down
	  a linux inode.

linux/fs/xfs/xfs_inode.c - 1.348
	- pass flush mode into xfs_finish_reclaim instead of a flag

linux/fs/xfs/linux/xfs_vnode.c - 1.96
	- Fail a vn_get on a vnode who's inode is being freed