From: Stefan Hajnoczi Date: Mon, 4 Mar 2013 14:02:30 +0000 (+0100) Subject: qcow2: flush refcount cache correctly in alloc_refcount_block() X-Git-Tag: v1.4.1~27 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=02ea844746e072fccd30b046a383265434d3dde8;p=thirdparty%2Fqemu.git qcow2: flush refcount cache correctly in alloc_refcount_block() update_refcount() affects the refcount cache, it does not write to disk. Therefore bdrv_flush(bs->file) does nothing. We need to flush the refcount cache in order to write out the refcount updates! While we're here also add error returns when qcow2_cache_flush() fails. Signed-off-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf (cherry picked from commit 9991923b262dc35f6dd8393ab4853edd7fc3724f) Signed-off-by: Michael Roth --- diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index bc1784c30ef..6a7a2301598 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -201,7 +201,10 @@ static int alloc_refcount_block(BlockDriverState *bs, *refcount_block = NULL; /* We write to the refcount table, so we might depend on L2 tables */ - qcow2_cache_flush(bs, s->l2_table_cache); + ret = qcow2_cache_flush(bs, s->l2_table_cache); + if (ret < 0) { + return ret; + } /* Allocate the refcount block itself and mark it as used */ int64_t new_block = alloc_clusters_noref(bs, s->cluster_size); @@ -237,7 +240,10 @@ static int alloc_refcount_block(BlockDriverState *bs, goto fail_block; } - bdrv_flush(bs->file); + ret = qcow2_cache_flush(bs, s->refcount_block_cache); + if (ret < 0) { + goto fail_block; + } /* Initialize the new refcount block only after updating its refcount, * update_refcount uses the refcount cache itself */