From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60868) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W7dBi-0006Tf-Bb for qemu-devel@nongnu.org; Sun, 26 Jan 2014 22:48:48 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W7dBa-0003Ch-Ne for qemu-devel@nongnu.org; Sun, 26 Jan 2014 22:48:42 -0500 Received: from mx1.redhat.com ([209.132.183.28]:63632) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W7dBa-0003Cc-FI for qemu-devel@nongnu.org; Sun, 26 Jan 2014 22:48:34 -0500 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s0R3mXo2002043 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sun, 26 Jan 2014 22:48:33 -0500 From: Fam Zheng Date: Mon, 27 Jan 2014 11:48:11 +0800 Message-Id: <1390794497-26281-6-git-send-email-famz@redhat.com> In-Reply-To: <1390794497-26281-1-git-send-email-famz@redhat.com> References: <1390794497-26281-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v12 05/11] block: Add bdrv_set_backing_hd() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, rjones@redhat.com, armbru@redhat.com, imain@redhat.com, stefanha@redhat.com, pbonzini@redhat.com This is the common but non-trivial steps to assign or change the backing_hd of BDS. Signed-off-by: Fam Zheng --- block.c | 39 ++++++++++++++++++++++++++++++--------- include/block/block.h | 1 + 2 files changed, 31 insertions(+), 9 deletions(-) diff --git a/block.c b/block.c index 8000ac0..af8922b 100644 --- a/block.c +++ b/block.c @@ -1072,6 +1072,31 @@ fail: return ret; } +void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) +{ + if (bs->backing_hd) { + bdrv_unref(bs->backing_hd); + } + + bs->backing_hd = backing_hd; + if (!backing_hd) { + bs->backing_file[0] = '\0'; + bs->backing_format[0] = '\0'; + goto out; + } + pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename); + pstrcpy(bs->backing_format, sizeof(bs->backing_file), + backing_hd->drv ? backing_hd->drv->format_name : ""); + bdrv_ref(bs->backing_hd); + + pstrcpy(bs->backing_file, sizeof(bs->backing_file), + bs->backing_hd->file->filename); + pstrcpy(bs->backing_format, sizeof(bs->backing_format), + bs->backing_hd->drv->format_name); +out: + bdrv_refresh_limits(bs); +} + /* * Opens the backing file for a BlockDriverState if not yet open * @@ -1085,6 +1110,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) char backing_filename[PATH_MAX]; int back_flags, ret; BlockDriver *back_drv = NULL; + BlockDriverState *backing_hd; Error *local_err = NULL; if (bs->backing_hd != NULL) { @@ -1108,7 +1134,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) sizeof(backing_filename)); } - bs->backing_hd = bdrv_new(""); + backing_hd = bdrv_new(""); if (bs->backing_format[0] != '\0') { back_drv = bdrv_find_format(bs->backing_format); @@ -1118,23 +1144,18 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_COPY_ON_READ); - ret = bdrv_open(bs->backing_hd, + ret = bdrv_open(backing_hd, *backing_filename ? backing_filename : NULL, options, back_flags, back_drv, &local_err); if (ret < 0) { - bdrv_unref(bs->backing_hd); - bs->backing_hd = NULL; + bdrv_unref(backing_hd); bs->open_flags |= BDRV_O_NO_BACKING; error_setg(errp, "Could not open backing file: %s", error_get_pretty(local_err)); error_free(local_err); return ret; } - - if (bs->backing_hd->file) { - pstrcpy(bs->backing_file, sizeof(bs->backing_file), - bs->backing_hd->file->filename); - } + bdrv_set_backing_hd(bs, backing_hd); /* Recalculate the BlockLimits with the backing file */ bdrv_refresh_limits(bs); diff --git a/include/block/block.h b/include/block/block.h index 9125bbe..f449753 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -208,6 +208,7 @@ int bdrv_file_open(BlockDriverState **pbs, const char *filename, int bdrv_open_image(BlockDriverState **pbs, const char *filename, QDict *options, const char *bdref_key, int flags, bool force_raw, bool allow_none, Error **errp); +void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd); int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp); int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options, int flags, BlockDriver *drv, Error **errp); -- 1.8.5.3