From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Jackson Subject: [PATCH 1/9] libxl: disks: Make LIBXL_DISK_BACKEND_UNKNOWN work Date: Thu, 2 Jun 2011 18:55:38 +0100 Message-ID: <1307037346-31251-2-git-send-email-ian.jackson@eu.citrix.com> References: <1307037346-31251-1-git-send-email-ian.jackson@eu.citrix.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1307037346-31251-1-git-send-email-ian.jackson@eu.citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com Cc: Ian Jackson List-Id: xen-devel@lists.xenproject.org libxl callers should not be required to specify the backend if they don't want to. So LIBXL_DISK_BACKEND_UNKNOWN should instruct libxl to choose the backend for itself. For now, we do this by simply treating it the same as BACKEND_TAP, which itself falls back to other methods. More thorough fixes for the disk handling will follow. Signed-off-by: Ian Jackson --- tools/libxl/libxl.c | 17 ++++++++++++++++- 1 files changed, 16 insertions(+), 1 deletions(-) diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c index c21cfe7..58df99c 100644 --- a/tools/libxl/libxl.c +++ b/tools/libxl/libxl.c @@ -991,6 +991,21 @@ int libxl_device_disk_add(libxl_ctx *ctx, uint32_t domid, libxl_device_disk *dis device.domid = domid; device.kind = DEVICE_VBD; + + /* + * Fixing the incoming backend type to try to decide on which + * backend to use. Unfortunately at the moment this code is + * utterly broken, but it more or less works. + */ + + /* + * Backend type UNKNOWN should mean "caller does not want to specify", + * not "break pointlessely". (Callers should not be required to + * specify the backend if they don't want to.) + */ + if (disk->backend == LIBXL_DISK_BACKEND_UNKNOWN) + disk->backend = LIBXL_DISK_BACKEND_TAP; + /* If blktap is not available then fallback to qdisk */ if (disk->backend == LIBXL_DISK_BACKEND_TAP && !libxl__blktap_enabled(&gc)) disk->backend = LIBXL_DISK_BACKEND_QDISK; @@ -1138,6 +1153,7 @@ char * libxl_device_disk_local_attach(libxl_ctx *ctx, libxl_device_disk *disk) dev = disk->pdev_path; break; case LIBXL_DISK_BACKEND_TAP: + case LIBXL_DISK_BACKEND_UNKNOWN: if (disk->format == LIBXL_DISK_FORMAT_VHD || disk->format == LIBXL_DISK_FORMAT_RAW) { @@ -1175,7 +1191,6 @@ char * libxl_device_disk_local_attach(libxl_ctx *ctx, libxl_device_disk *disk) disk->pdev_path); dev = disk->pdev_path; break; - case LIBXL_DISK_BACKEND_UNKNOWN: default: LIBXL__LOG(ctx, LIBXL__LOG_ERROR, "unrecognized disk backend " "type: %d", disk->backend); -- 1.5.6.5