From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53580) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bpvRm-0003ZA-8N for qemu-devel@nongnu.org; Fri, 30 Sep 2016 06:53:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bpvRi-00008i-51 for qemu-devel@nongnu.org; Fri, 30 Sep 2016 06:53:41 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:40948 helo=relay.sw.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bpvRh-00004r-Oq for qemu-devel@nongnu.org; Fri, 30 Sep 2016 06:53:38 -0400 From: Vladimir Sementsov-Ogievskiy Date: Fri, 30 Sep 2016 13:53:18 +0300 Message-Id: <1475232808-4852-13-git-send-email-vsementsov@virtuozzo.com> In-Reply-To: <1475232808-4852-1-git-send-email-vsementsov@virtuozzo.com> References: <1475232808-4852-1-git-send-email-vsementsov@virtuozzo.com> Subject: [Qemu-devel] [PATCH 12/22] qcow2-bitmap: add IN_USE flag List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org, qemu-devel@nongnu.org Cc: kwolf@redhat.com, mreitz@redhat.com, armbru@redhat.com, eblake@redhat.com, jsnow@redhat.com, famz@redhat.com, den@openvz.org, stefanha@redhat.com, vsementsov@virtuozzo.com, pbonzini@redhat.com This flag means that the bitmap is now in use by the software or was not successfully saved. In any way, with this flag set the bitmap data must be considered inconsistent and should not be loaded. With current implementation this flag is never set, as we just remove bitmaps from the image after loading. But it defined in qcow2 spec and must be handled. Also, it can be used in future, if async schemes of bitmap loading/saving are implemented. We also remove in-use bitmaps from the image on open. Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/qcow2-bitmap.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index a5be25a..8cf40f0 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -28,6 +28,7 @@ #include "qemu/osdep.h" #include "qapi/error.h" #include "qemu/cutils.h" +#include "exec/log.h" #include "block/block_int.h" #include "block/qcow2.h" @@ -44,7 +45,8 @@ #define BME_MAX_NAME_SIZE 1023 /* Bitmap directory entry flags */ -#define BME_RESERVED_FLAGS 0xfffffffd +#define BME_RESERVED_FLAGS 0xfffffffc +#define BME_FLAG_IN_USE 1 #define BME_FLAG_AUTO (1U << 1) /* bits [1, 8] U [56, 63] are reserved */ @@ -287,6 +289,11 @@ static BdrvDirtyBitmap *load_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap = NULL; char *name = g_strndup(dir_entry_name_notcstr(entry), entry->name_size); + if (entry->flags & BME_FLAG_IN_USE) { + error_setg(errp, "Bitmap '%s' is in use", name); + goto fail; + } + ret = bitmap_table_load(bs, entry, &bitmap_table); if (ret < 0) { error_setg_errno(errp, -ret, @@ -533,6 +540,14 @@ int qcow2_read_bitmaps(BlockDriverState *bs, Error **errp) for_each_bitmap_dir_entry(e, dir, dir_size) { uint32_t fl = e->flags; + if (fl & BME_FLAG_IN_USE) { + qemu_log("qcow2 warning: " + "removing in_use bitmap '%.*s' for image %s.\n", + e->name_size, (char *)(e + 1), bdrv_get_device_or_node_name(bs)); + + continue; + } + if (fl & BME_FLAG_AUTO) { BdrvDirtyBitmap *bitmap = load_bitmap(bs, e, errp); if (bitmap == NULL) { -- 1.8.3.1