kernfs: handle poll correctly on 'direct_read' files.
authorNeilBrown <neilb@suse.de>
Sun, 15 Mar 2015 23:44:52 +0000 (10:44 +1100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 16 Mar 2015 20:51:20 +0000 (21:51 +0100)
commit7cff4b1836a9d3f18aadd6e88fd43055e2ff4132
tree70647b3ffbae2a9534d7baae276d9e48da58605b
parent06e5801b8cb3fc057d88cb4dc03c0b64b2744cda
kernfs: handle poll correctly on 'direct_read' files.

Kernfs supports two styles of read: direct_read and seqfile_read.

The latter supports 'poll' correctly thanks to the update of
'->event' in kernfs_seq_show.
The former does not as '->event' is never updated on a read.

So add an appropriate update in kernfs_file_direct_read().

This was noticed because some 'md' sysfs attributes were
recently changed to use direct reads.

Reported-by: Prakash Punnoor <prakash@punnoor.de>
Reported-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Fixes: 750f199ee8b578062341e6ddfe36c59ac8ff2dcb
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/kernfs/file.c