From 9956688a8f05ddafb36b9d50d1ff7fbf67464275 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 24 Jul 2019 19:12:36 +0200 Subject: [PATCH] vhdx: Fix .bdrv_has_zero_init() Fixed VHDX images cannot guarantee to be zero-initialized. If the image has the "fixed" subformat, forward the call to the underlying storage node. Reported-by: Stefano Garzarella Signed-off-by: Max Reitz Message-id: 20190724171239.8764-9-mreitz@redhat.com Reviewed-by: Maxim Levitsky Signed-off-by: Max Reitz --- block/vhdx.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/block/vhdx.c b/block/vhdx.c index a02d1c99a7..6a09d0a55c 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -2075,6 +2075,30 @@ static int coroutine_fn vhdx_co_check(BlockDriverState *bs, return 0; } +static int vhdx_has_zero_init(BlockDriverState *bs) +{ + BDRVVHDXState *s = bs->opaque; + int state; + + /* + * Check the subformat: Fixed images have all BAT entries present, + * dynamic images have none (right after creation). It is + * therefore enough to check the first BAT entry. + */ + if (!s->bat_entries) { + return 1; + } + + state = s->bat[0] & VHDX_BAT_STATE_BIT_MASK; + if (state == PAYLOAD_BLOCK_FULLY_PRESENT) { + /* Fixed subformat */ + return bdrv_has_zero_init(bs->file->bs); + } + + /* Dynamic subformat */ + return 1; +} + static QemuOptsList vhdx_create_opts = { .name = "vhdx-create-opts", .head = QTAILQ_HEAD_INITIALIZER(vhdx_create_opts.head), @@ -2128,7 +2152,7 @@ static BlockDriver bdrv_vhdx = { .bdrv_co_create_opts = vhdx_co_create_opts, .bdrv_get_info = vhdx_get_info, .bdrv_co_check = vhdx_co_check, - .bdrv_has_zero_init = bdrv_has_zero_init_1, + .bdrv_has_zero_init = vhdx_has_zero_init, .create_opts = &vhdx_create_opts, };