tree 64f8f993ab48978b5a3a13912bba685d48b1a04e
parent 8f778bbc542ddf8f6243b21d6aca087e709cabdc
author Al Viro <viro@zeniv.linux.org.uk> 1428356934 -0400
committer Al Viro <viro@zeniv.linux.org.uk> 1428357059 -0400

fix mremap() vs. ioctx_kill() race

teach ->mremap() method to return an error and have it fail for
aio mappings in process of being killed

Note that in case of ->mremap() failure we need to undo move_page_tables()
we'd already done; we could call ->mremap() first, but then the failure of
move_page_tables() would require undoing whatever _successful_ ->mremap()
has done, which would be a lot more headache in general.

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