tree 441e212766a0d2ad42a3c796b4beea999dbdd0d6
parent 5d01410fe4d92081f349b013a2e7a95429e4f2c9
author Al Viro <viro@zeniv.linux.org.uk> 1417114301 -0500
committer Al Viro <viro@zeniv.linux.org.uk> 1417131850 -0500

iov_iter.c: macros for iterating over iov_iter

iterate_all_kinds(iter, size, ident, step_iovec, step_bvec)
iterates through the ranges covered by iter (up to size bytes total),
repeating step_iovec or step_bvec for each of those.  ident is
declared in expansion of that thing, either as struct iovec or
struct bvec, and it contains the range we are currently looking
at.  step_bvec should be a void expression, step_iovec - a size_t
one, with non-zero meaning "stop here, that many bytes from this
range left".  In the end, the amount actually handled is stored
in size.

iov_iter_copy_from_user_atomic() and iov_iter_alignment() converted
to it.

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