tree 89aae8e9d832199906d413dcffd5b885bcee14fe
parent 7f7f25e82d54870df24d415a7007fbd327da027b
author Al Viro <viro@zeniv.linux.org.uk> 1392161861 -0500
committer Al Viro <viro@zeniv.linux.org.uk> 1399412160 -0400

new methods: ->read_iter() and ->write_iter()

Beginning to introduce those.  Just the callers for now, and it's
clumsier than it'll eventually become; once we finish converting
aio_read and aio_write instances, the things will get nicer.

For now, these guys are in parallel to ->aio_read() and ->aio_write();
they take iocb and iov_iter, with everything in iov_iter already
validated.  File offset is passed in iocb->ki_pos, iov/nr_segs -
in iov_iter.

Main concerns in that series are stack footprint and ability to
split the damn thing cleanly.

[fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>