From patchwork Tue Feb 1 05:26:32 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mohan Kumar M X-Patchwork-Id: 81275 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 DF1EFB70CD for ; Tue, 1 Feb 2011 16:28:49 +1100 (EST) Received: from localhost ([127.0.0.1]:33539 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pk8nG-0004v7-DT for incoming@patchwork.ozlabs.org; Tue, 01 Feb 2011 00:28:46 -0500 Received: from [140.186.70.92] (port=58402 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pk8lF-0004tp-20 for qemu-devel@nongnu.org; Tue, 01 Feb 2011 00:26:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pk8lC-0006kG-89 for qemu-devel@nongnu.org; Tue, 01 Feb 2011 00:26:39 -0500 Received: from e23smtp09.au.ibm.com ([202.81.31.142]:37141) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pk8lB-0006jp-N5 for qemu-devel@nongnu.org; Tue, 01 Feb 2011 00:26:38 -0500 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [202.81.31.247]) by e23smtp09.au.ibm.com (8.14.4/8.13.1) with ESMTP id p115QZRx031565 for ; Tue, 1 Feb 2011 16:26:35 +1100 Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p115QZHV1925354 for ; Tue, 1 Feb 2011 16:26:35 +1100 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p115QYLK025350 for ; Tue, 1 Feb 2011 16:26:34 +1100 Received: from explorer.in.ibm.com ([9.124.35.46]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p115QX0f025333; Tue, 1 Feb 2011 16:26:33 +1100 From: "M. Mohan Kumar" To: qemu-devel@nongnu.org Date: Tue, 1 Feb 2011 10:56:32 +0530 Message-Id: <1296537992-16687-1-git-send-email-mohan@in.ibm.com> X-Mailer: git-send-email 1.7.3.4 In-Reply-To: <1296537693-16406-1-git-send-email-mohan@in.ibm.com> References: <1296537693-16406-1-git-send-email-mohan@in.ibm.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 202.81.31.142 Cc: stefanha@gmail.com Subject: [Qemu-devel] [V4 PATCH 3/8] Add client side interfaces for chroot environment 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 Define QEMU side interfaces used for chroot environment. Signed-off-by: M. Mohan Kumar --- hw/9pfs/virtio-9p-chroot.c | 87 ++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 87 insertions(+), 0 deletions(-) diff --git a/hw/9pfs/virtio-9p-chroot.c b/hw/9pfs/virtio-9p-chroot.c index 5150ff0..b466d9a 100644 --- a/hw/9pfs/virtio-9p-chroot.c +++ b/hw/9pfs/virtio-9p-chroot.c @@ -111,6 +111,86 @@ static int chroot_read_request(int sockfd, V9fsFileObjectRequest *request) return 0; } +/* Receive file descriptor and error status from chroot process */ +static int v9fs_receivefd(int sockfd, int *error) +{ + struct msghdr msg = { }; + struct iovec iov; + union MsgControl msg_control; + struct cmsghdr *cmsg; + int retval, fd; + FdInfo fd_info; + + iov.iov_base = &fd_info; + iov.iov_len = sizeof(fd_info); + + memset(&msg, 0, sizeof(msg)); + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = &msg_control; + msg.msg_controllen = sizeof(msg_control); + + retval = recvmsg(sockfd, &msg, 0); + if (retval < 0) { + *error = EIO; + return -EIO; + } + + if (fd_info.fi_flags & FI_SOCKERR) { + return -EIO; + } + + /* If error is set, ancillary data is not present */ + if (fd_info.fi_error) { + *error = fd_info.fi_error; + return -1; + } + + if (!(fd_info.fi_flags & FI_FDVALID)) { + return 0; + } + + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) { + if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)) || + cmsg->cmsg_level != SOL_SOCKET || + cmsg->cmsg_type != SCM_RIGHTS) { + continue; + } + fd = *((int *)CMSG_DATA(cmsg)); + return fd; + } + + *error = EAGAIN; + return -1; +} + +/* + * V9fsFileObjectRequest is written into the socket by QEMU process. + * Then this request is read by chroot process using read_request function + */ +static int v9fs_write_request(int sockfd, V9fsFileObjectRequest *request) +{ + int retval, length; + char *buff, *buffp; + + length = sizeof(request->data) + request->data.path_len + + request->data.oldpath_len; + + buff = qemu_malloc(length); + buffp = buff; + memcpy(buffp, &request->data, sizeof(request->data)); + buffp += sizeof(request->data); + memcpy(buffp, request->path.path, request->data.path_len); + buffp += request->data.path_len; + memcpy(buffp, request->path.old_path, request->data.oldpath_len); + + retval = qemu_write_full(sockfd, buff, length); + if (retval != length) { + return EIO; + } + return 0; +} + static int chroot_daemonize(int chroot_sock) { sigset_t sigset; @@ -139,6 +219,12 @@ static int chroot_daemonize(int chroot_sock) return 0; } +static void chroot_dummy(void) +{ + (void)v9fs_receivefd; + (void)v9fs_write_request; +} + /* * Fork a process and chroot into the share path. Communication * between qemu process and chroot process happens via socket @@ -184,6 +270,7 @@ int v9fs_chroot(FsContext *fs_ctx) error = qemu_write_full(chroot_sock, &code, sizeof(code)); _exit(1); } + chroot_dummy(); /* * Write 0 to chroot socket to indicate chroot process creation is