PARTIAL TAKE 942818 - Allow swidth to be exposed to userspace via stat(2)

[dgc@xxxxxxx (David Chinner)]

Introduce two new mount options (nolargeio/largeio) to
allow filesystems to expose the filesystem stripe width
in stat(2) rather than the page cache size. This allows
applications requiring high bandwidth to easily
determine the optimum I/O size for the underlying
filesystem. The default is to report the page cache size
(i.e. "nolargeio").

Date:  Fri Sep 16 13:32:17 AEST 2005
Workarea:  chook.melbourne.sgi.com:/build/dgc/isms/xfs-linux
Inspected by:  nathans

The following file(s) were checked into:
  longdrop.melbourne.sgi.com:/isms/xfs-kern/xfs-linux-melb


Modid:  xfs-linux-melb:xfs-kern:23830a
xfs_vnodeops.c - 1.651 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/xfs_vnodeops.c.diff?r1=text&tr1=1.651&r2=text&tr2=1.650&f=h
        - Clean up prefered I/O size selection.

xfs_vfsops.c - 1.474 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/xfs_vfsops.c.diff?r1=text&tr1=1.474&r2=text&tr2=1.473&f=h
xfs_clnt.h - 1.48 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/xfs_clnt.h.diff?r1=text&tr1=1.48&r2=text&tr2=1.47&f=h
        - Introduce prefered I/O size mount option selection.

xfs_mount.h - 1.203 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/xfs_mount.h.diff?r1=text&tr1=1.203&r2=text&tr2=1.202&f=h
        - Introduce prefered I/O size mount option selection
          and calculation.

linux-2.6/xfs_vnode.c - 1.133 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/linux-2.6/xfs_vnode.c.diff?r1=text&tr1=1.133&r2=text&tr2=1.132&f=h
linux-2.6/xfs_super.c - 1.345 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/linux-2.6/xfs_super.c.diff?r1=text&tr1=1.345&r2=text&tr2=1.344&f=h
linux-2.4/xfs_vnode.c - 1.133 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/linux-2.4/xfs_vnode.c.diff?r1=text&tr1=1.133&r2=text&tr2=1.132&f=h
linux-2.4/xfs_super.c - 1.314 - changed
http://oss.sgi.com/cgi-bin/cvsweb.cgi/xfs-linux/linux-2.4/xfs_super.c.diff?r1=text&tr1=1.314&r2=text&tr2=1.313&f=h
        - Set inode block size to the preferred size for the filesystem