tree 2d9095867f2272e11ac0831e4d312811220d84d6
parent ee40fb2948fc99096836995d4f3ddcc0efbac790
author Tal Shorer <tal.shorer@gmail.com> 1467365337 +0300
committer Christoph Hellwig <hch@lst.de> 1468152138 +0900

configfs: don't set buffer_needs_fill to zero if show() returns error

A confgifs attribute's show() callback is called once the first time
the user attempts to read from it. If it returns an error, that
error is returned to the user. However, the open file's
buffer_needs_fill is still set to zero and consecutive read() calls
will find an empty buffer that doesn't need filling and return 0 to
the user. This could give the user the wrong impression that the
attribute was read successfully.

Fix this by not setting buffer_needs_fill if show() returns an error,
making consecutive read() calls call show() again and either get an
error again or get data.

Signed-off-by: Tal Shorer <tal.shorer@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>