Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935369Ab1ETJxL (ORCPT ); Fri, 20 May 2011 05:53:11 -0400 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:34411 "EHLO www.etchedpixels.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752839Ab1ETJxI (ORCPT ); Fri, 20 May 2011 05:53:08 -0400 Date: Fri, 20 May 2011 10:54:17 +0100 From: Alan Cox To: Timur Tabi Cc: , , , , , , Subject: Re: [PATCH 6/7] tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver Message-ID: <20110520105417.562c7341@lxorguk.ukuu.org.uk> In-Reply-To: <4DD53FDD.7070503@freescale.com> References: <1305813272-31826-1-git-send-email-timur@freescale.com> <1305813272-31826-7-git-send-email-timur@freescale.com> <20110519153358.5876f310@lxorguk.ukuu.org.uk> <4DD53FDD.7070503@freescale.com> X-Mailer: Claws Mail 3.7.8 (GTK+ 2.22.0; x86_64-redhat-linux-gnu) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1235 Lines: 26 On Thu, 19 May 2011 11:05:49 -0500 Timur Tabi wrote: > Alan Cox wrote: > >> > + /* Pass the received data to the tty layer. Note that this > >> > + * function calls tty_buffer_request_room(), so I'm not sure if > >> > + * we should have also called tty_buffer_request_room(). > >> > + */ > >> > + ret = tty_insert_flip_string(ttys, buffer, len); > > > You only need to request_room in advance if you can't handle the case > > where the insert_flip_string returns less than you stuffed down it. > > If tty_insert_flip_string() returns less than I stuffed down it, the characters > it didn't accept will be dropped. That's because once I receive them, I have > nowhere else to put them. I suppose I could implement a receive FIFO, but that > seems overkill. If calling tty_buffer_request_room() ensures that > tty_insert_flip_string() always accepts all the characters, I would rather do that. I was answering the question in the comment in the code... -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/