From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36996) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XNTv4-0006vc-Fe for qemu-devel@nongnu.org; Fri, 29 Aug 2014 17:41:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XNTuy-00082J-Aq for qemu-devel@nongnu.org; Fri, 29 Aug 2014 17:41:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46773) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XNTuy-00082C-35 for qemu-devel@nongnu.org; Fri, 29 Aug 2014 17:41:12 -0400 From: Max Reitz Date: Fri, 29 Aug 2014 23:40:53 +0200 Message-Id: <1409348463-16627-2-git-send-email-mreitz@redhat.com> In-Reply-To: <1409348463-16627-1-git-send-email-mreitz@redhat.com> References: <1409348463-16627-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v5 01/11] qcow2: Calculate refcount block entry count List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , =?UTF-8?q?Beno=C3=AEt=20Canet?= , Max Reitz The size of a refblock entry is (in theory) variable; calculate therefore the number of entries per refblock and the according bit shift (1 << x == entry count) when opening an image. Signed-off-by: Max Reitz --- block/qcow2.c | 2 ++ block/qcow2.h | 2 ++ 2 files changed, 4 insertions(+) diff --git a/block/qcow2.c b/block/qcow2.c index f9e045f..172ad00 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -689,6 +689,8 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ s->l2_size = 1 << s->l2_bits; + s->refcount_block_bits = s->cluster_bits - (s->refcount_order - 3); + s->refcount_block_size = 1 << s->refcount_block_bits; bs->total_sectors = header.size / 512; s->csize_shift = (62 - (s->cluster_bits - 8)); s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; diff --git a/block/qcow2.h b/block/qcow2.h index 6aeb7ea..7c01fb7 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -222,6 +222,8 @@ typedef struct BDRVQcowState { int l2_size; int l1_size; int l1_vm_state_index; + int refcount_block_bits; + int refcount_block_size; int csize_shift; int csize_mask; uint64_t cluster_offset_mask; -- 2.1.0