[PATCH 0/2] sys_write() should write all valid data

[Vitaly Mayatskikh <v.mayatskih@gmail.com>]

There's user-visible misbehavour in sys_write(): when user tries to put
down to disk some data, which crosses boundary of existing memory, sys_write()
either immediately returns with EFAULT or writes first page(s).

Next 2 patches make sys_write()'s behaviour more consistent: it tries now
to write down all what it can.

Vitaly Mayatskikh (2):
  Introduce check_readable_bytes()
  Perform checks in iov_iter_fault_in_readable() with
    check_readable_bytes()

 fs/fuse/file.c          |    6 ++++--
 include/linux/pagemap.h |   35 +++++++++++++++++++++++++++++++++++
 mm/filemap.c            |   13 +++++++++----
 3 files changed, 48 insertions(+), 6 deletions(-)