From patchwork Mon Sep 5 16:18:26 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: 113396 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id BD521B6F7D for ; Tue, 6 Sep 2011 02:20:31 +1000 (EST) Received: from localhost ([::1]:38388 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0buN-0000kD-UW for incoming@patchwork.ozlabs.org; Mon, 05 Sep 2011 12:20:27 -0400 Received: from eggs.gnu.org ([140.186.70.92]:54845) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0bsq-0005kC-4O for qemu-devel@nongnu.org; Mon, 05 Sep 2011 12:18:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R0bsm-0005Fw-0r for qemu-devel@nongnu.org; Mon, 05 Sep 2011 12:18:51 -0400 Received: from e28smtp03.in.ibm.com ([122.248.162.3]:54423) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R0bsl-0005D8-AH for qemu-devel@nongnu.org; Mon, 05 Sep 2011 12:18:47 -0400 Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by e28smtp03.in.ibm.com (8.14.4/8.13.1) with ESMTP id p85GIdfU027602 for ; Mon, 5 Sep 2011 21:48:39 +0530 Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p85GIcet3149902 for ; Mon, 5 Sep 2011 21:48:38 +0530 Received: from d28av05.in.ibm.com (loopback [127.0.0.1]) by d28av05.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p85GIcm1029165 for ; Tue, 6 Sep 2011 02:18:38 +1000 Received: from explorer.in.ibm.com ([9.79.187.208]) by d28av05.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p85GIbFq029092; Tue, 6 Sep 2011 02:18:38 +1000 From: "M. Mohan Kumar" To: qemu-devel@nongnu.org, Anthony Liguori , Stefan Hajnoczi Date: Mon, 5 Sep 2011 21:48:26 +0530 Message-Id: <1315239516-4451-6-git-send-email-mohan@in.ibm.com> X-Mailer: git-send-email 1.7.6 In-Reply-To: <1315239516-4451-1-git-send-email-mohan@in.ibm.com> References: <1315239516-4451-1-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: 122.248.162.3 Subject: [Qemu-devel] [PATCH V12 05/15] hw/9pfs: Support for opening a file in chroot environment X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org This patch adds both chroot worker and qemu side support to open a file/ directory in the chroot environment Signed-off-by: M. Mohan Kumar --- hw/9pfs/virtio-9p-chroot.c | 29 ++++++++++++---- hw/9pfs/virtio-9p-chroot.h | 2 +- hw/9pfs/virtio-9p-local.c | 79 ++++++++++++++++++++++++++++++++++++++++++-- 3 files changed, 98 insertions(+), 12 deletions(-) diff --git a/hw/9pfs/virtio-9p-chroot.c b/hw/9pfs/virtio-9p-chroot.c index 63de410..f5b3abc 100644 --- a/hw/9pfs/virtio-9p-chroot.c +++ b/hw/9pfs/virtio-9p-chroot.c @@ -91,13 +91,26 @@ static int v9fs_write_request(int sockfd, V9fsFileObjectRequest *request) return 0; } -/* - * This patch adds v9fs_receivefd and v9fs_write_request functions, - * but there is no caller. To avoid compiler warning message, - * refer these two functions - */ -void chroot_dummy(void) +/* Return opened file descriptor on success or -errno on error */ +int v9fs_request(FsContext *fs_ctx, V9fsFileObjectRequest *request) { - (void)v9fs_receivefd; - (void)v9fs_write_request; + int fd, sock_error; + qemu_mutex_lock(&fs_ctx->chroot_mutex); + if (fs_ctx->chroot_socket == -1) { + goto error; + } + if (v9fs_write_request(fs_ctx->chroot_socket, request) < 0) { + goto error; + } + fd = v9fs_receivefd(fs_ctx->chroot_socket, &sock_error); + if (fd < 0 && sock_error) { + goto error; + } + qemu_mutex_unlock(&fs_ctx->chroot_mutex); + return fd; +error: + close(fs_ctx->chroot_socket); + fs_ctx->chroot_socket = -1; + qemu_mutex_unlock(&fs_ctx->chroot_mutex); + return -EIO; } diff --git a/hw/9pfs/virtio-9p-chroot.h b/hw/9pfs/virtio-9p-chroot.h index a817bcf..326238d 100644 --- a/hw/9pfs/virtio-9p-chroot.h +++ b/hw/9pfs/virtio-9p-chroot.h @@ -35,6 +35,6 @@ typedef struct V9fsFileObjectRequest } V9fsFileObjectRequest; int v9fs_chroot(FsContext *fs_ctx); -void chroot_dummy(void); +int v9fs_request(FsContext *fs_ctx, V9fsFileObjectRequest *or); #endif /* _QEMU_VIRTIO_9P_CHROOT_H */ diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c index 7a46e93..a91adb8 100644 --- a/hw/9pfs/virtio-9p-local.c +++ b/hw/9pfs/virtio-9p-local.c @@ -14,6 +14,9 @@ #include "hw/virtio.h" #include "virtio-9p.h" #include "virtio-9p-xattr.h" +#include "qemu_socket.h" +#include "fsdev/qemu-fsdev.h" +#include "virtio-9p-chroot.h" #include #include #include @@ -24,6 +27,63 @@ #include #include +/* Helper routine to fill V9fsFileObjectRequest structure */ +static int fill_fileobjectrequest(V9fsFileObjectRequest *request, + const char *oldpath, const char *path, int flags, + FsCred *credp, int type) +{ + if (oldpath && strlen(oldpath) >= PATH_MAX) { + return -ENAMETOOLONG; + } + /* path can't be NULL */ + if (!path) { + return -EFAULT; + } + + if (strlen(path) >= PATH_MAX) { + return -ENAMETOOLONG; + } + strcpy(request->path.path, path); + if (oldpath) { + strcpy(request->path.old_path, oldpath); + } else { + request->path.old_path[0] = '\0'; + } + + memset(&request->data, 0, sizeof(request->data)); + if (credp) { + request->data.mode = credp->fc_mode; + request->data.uid = credp->fc_uid; + request->data.gid = credp->fc_gid; + request->data.dev = credp->fc_rdev; + } + + request->data.flags = flags; + request->data.type = type; + return 0; +} + +static int passthrough_request(FsContext *fs_ctx, const char *old_path, + const char *path, int flags, FsCred *credp, int type) +{ + V9fsFileObjectRequest request; + int retval; + + retval = fill_fileobjectrequest(&request, old_path, path, flags, credp, + type); + if (retval < 0) { + errno = -retval; + return -1; + } + + retval = v9fs_request(fs_ctx, &request); + if (retval < 0) { + errno = -retval; + retval = -1; + } + return retval; +} + static int local_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf) { int err; @@ -157,7 +217,11 @@ static int local_open(FsContext *ctx, V9fsPath *fs_path, char buffer[PATH_MAX]; char *path = fs_path->data; - fs->fd = open(rpath(ctx, path, buffer), flags); + if (ctx->fs_sm == SM_PASSTHROUGH) { + fs->fd = passthrough_request(ctx, NULL, path, flags, NULL, T_OPEN); + } else { + fs->fd = open(rpath(ctx, path, buffer), flags); + } return fs->fd; } @@ -167,7 +231,17 @@ static int local_opendir(FsContext *ctx, char buffer[PATH_MAX]; char *path = fs_path->data; - fs->dir = opendir(rpath(ctx, path, buffer)); + if (ctx->fs_sm == SM_PASSTHROUGH) { + int fd; + fd = passthrough_request(ctx, NULL, path, O_DIRECTORY, NULL, T_OPEN); + if (fd < 0) { + return -1; + } + fs->dir = fdopendir(fd); + } else { + fs->dir = opendir(rpath(ctx, path, buffer)); + } + if (!fs->dir) { return -1; } @@ -426,7 +500,6 @@ out: return err; } - static int local_symlink(FsContext *fs_ctx, const char *oldpath, V9fsPath *dir_path, const char *name, FsCred *credp) {