This patch is to offer common accounting data collection method at I/O for
various accounting packages including BSD accounting, ELSA, CSA and any
other acct packages that use a common layer of data collection.

Patch is made to fs/read_write.c to collect per process data on character
read/written in bytes and number of read/write syscalls made.

New struct fields are added to task_struct to store the data.

These data are collected on per process basis.
Signed-off-by: Jay Lan <jlan@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>