From patchwork Tue May 4 10:52:46 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amit Shah X-Patchwork-Id: 51584 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 14DD7B7D1B for ; Tue, 4 May 2010 21:11:07 +1000 (EST) Received: from localhost ([127.0.0.1]:46059 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1O9G0W-00087G-MX for incoming@patchwork.ozlabs.org; Tue, 04 May 2010 07:09:44 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1O9FmU-0003aA-4a for qemu-devel@nongnu.org; Tue, 04 May 2010 06:55:14 -0400 Received: from [140.186.70.92] (port=33682 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1O9FmQ-0003Z0-AI for qemu-devel@nongnu.org; Tue, 04 May 2010 06:55:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1O9Fm9-0006DB-Jp for qemu-devel@nongnu.org; Tue, 04 May 2010 06:55:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21542) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1O9Fm7-0006CQ-Go for qemu-devel@nongnu.org; Tue, 04 May 2010 06:54:53 -0400 Received: from int-mx05.intmail.prod.int.phx2.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.18]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o44AshiN003054 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 4 May 2010 06:54:44 -0400 Received: from localhost (vpn-224-130.phx2.redhat.com [10.3.224.130]) by int-mx05.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o44AsgW6001042; Tue, 4 May 2010 06:54:43 -0400 From: Amit Shah To: qemu list Date: Tue, 4 May 2010 16:22:46 +0530 Message-Id: <1272970367-24647-6-git-send-email-amit.shah@redhat.com> In-Reply-To: <1272970367-24647-5-git-send-email-amit.shah@redhat.com> References: <1272970367-24647-1-git-send-email-amit.shah@redhat.com> <1272970367-24647-2-git-send-email-amit.shah@redhat.com> <1272970367-24647-3-git-send-email-amit.shah@redhat.com> <1272970367-24647-4-git-send-email-amit.shah@redhat.com> <1272970367-24647-5-git-send-email-amit.shah@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.18 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. Cc: Amit Shah , Paul Brook , Gerd Hoffmann , Juan Quintela Subject: [Qemu-devel] [PATCH v5 5/6] char: unix/tcp: Add a non-blocking write handler X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Add a non-blocking write handler that can return with -EAGAIN to the caller and also callback when the socket becomes writable. Non-blocking writes are only enabled for sockets that are opened in non-blocking mode and only for callers that have registered a callback handler for resuming writes. Signed-off-by: Amit Shah --- qemu-char.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 50 insertions(+), 0 deletions(-) diff --git a/qemu-char.c b/qemu-char.c index d383c8f..2d74087 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -2126,11 +2126,60 @@ static void tcp_chr_read(void *opaque) } } +static void tcp_chr_write_unblocked(void *opaque) +{ + CharDriverState *chr = opaque; + TCPCharDriver *s = chr->opaque; + + assert(chr->write_blocked && chr->chr_write_unblocked); + + chr->write_blocked = false; + qemu_set_fd_handler2(s->fd, tcp_chr_read_poll, tcp_chr_read, NULL, chr); + chr->chr_write_unblocked(chr->handler_opaque); +} + +static ssize_t tcp_chr_write_nb(CharDriverState *chr, const uint8_t *buf, + size_t len) +{ + TCPCharDriver *s = chr->opaque; + ssize_t ret; + + if (!s->connected) { + /* XXX: indicate an error? */ + return len; + } + + ret = send_all(s->fd, buf, len, true); + if (ret == -EAGAIN) { + chr->write_blocked = true; + qemu_set_fd_handler2(s->fd, tcp_chr_read_poll, + tcp_chr_read, tcp_chr_write_unblocked, chr); + } + return ret; +} + static void tcp_chr_connect(void *opaque) { CharDriverState *chr = opaque; TCPCharDriver *s = chr->opaque; + IOHandler *write_cb; + int flags; + bool nonblock; + + flags = fcntl(s->fd, F_GETFL); + if (flags == -1) { + flags = 0; + } + nonblock = flags & O_NONBLOCK; + + write_cb = NULL; + chr->nonblock = false; + if (nonblock && chr->chr_write_unblocked) { + write_cb = chr->chr_write_unblocked; + chr->nonblock = true; + } + chr->write_blocked = false; s->connected = 1; qemu_set_fd_handler2(s->fd, tcp_chr_read_poll, tcp_chr_read, NULL, chr); @@ -2263,6 +2312,7 @@ static CharDriverState *qemu_chr_open_socket(QemuOpts *opts) chr->opaque = s; chr->chr_write = tcp_chr_write; + chr->chr_write_nb = tcp_chr_write_nb; chr->chr_close = tcp_chr_close; chr->get_msgfd = tcp_get_msgfd;