From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39615) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XiPdG-0007y1-O0 for qemu-devel@nongnu.org; Sun, 26 Oct 2014 11:21:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XiPd7-0005xE-AT for qemu-devel@nongnu.org; Sun, 26 Oct 2014 11:21:26 -0400 Received: from mail-pa0-x232.google.com ([2607:f8b0:400e:c03::232]:41770) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XiPd6-0005wm-FM for qemu-devel@nongnu.org; Sun, 26 Oct 2014 11:21:17 -0400 Received: by mail-pa0-f50.google.com with SMTP id eu11so3929350pac.9 for ; Sun, 26 Oct 2014 08:21:12 -0700 (PDT) From: Jun Li Date: Sun, 26 Oct 2014 23:20:48 +0800 Message-Id: <1414336849-21179-3-git-send-email-junmuzi@gmail.com> In-Reply-To: <1414336849-21179-1-git-send-email-junmuzi@gmail.com> References: <1414336849-21179-1-git-send-email-junmuzi@gmail.com> Subject: [Qemu-devel] [PATCH v5 2/3] qcow2: add update refcount table realization for update_refcount List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, juli@redhat.com, famz@redhat.com, Jun Li , stefanha@redhat.com When every item of refcount block is NULL, free refcount block and reset the corresponding item of refcount table with NULL. At the same time, put this cluster to s->free_cluster_index. Signed-off-by: Jun Li --- v5: Just instead write_reftable_entry with bdrv_pwrite_sync. As write_reftable_entry has deleted from the source code. v4: Do not change anything for this commit id. v3: Add handle self-describing refcount blocks. --- block/qcow2-refcount.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 48 insertions(+), 1 deletion(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 1477031..abb4f6d 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -596,6 +596,53 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, if (refcount == 0 && s->discard_passthrough[type]) { update_refcount_discard(bs, cluster_offset, s->cluster_size); } + + unsigned int refcount_table_index; + refcount_table_index = cluster_index >> s->refcount_block_bits; + + uint64_t refcount_block_offset = + s->refcount_table[refcount_table_index] & REFT_OFFSET_MASK; + + int64_t self_block_index = refcount_block_offset >> s->cluster_bits; + int self_block_index2 = (refcount_block_offset >> s->cluster_bits) & + ((1 << s->refcount_block_bits) - 1); + + /* When refcount block is NULL, update refcount table */ + if (!be16_to_cpu(refcount_block[0]) || self_block_index2 == 0) { + int k; + int refcount_block_entries = s->cluster_size / + sizeof(refcount_block[0]); + for (k = 0; k < refcount_block_entries; k++) { + if (k == self_block_index2) { + k++; + } + + if (be16_to_cpu(refcount_block[k])) { + break; + } + } + + if (k == refcount_block_entries) { + if (self_block_index < s->free_cluster_index) { + s->free_cluster_index = self_block_index; + } + + /* update refcount table */ + s->refcount_table[refcount_table_index] = 0; + uint64_t data64 = cpu_to_be64(0); + ret = bdrv_pwrite_sync(bs->file, + s->refcount_table_offset + + refcount_table_index * + sizeof(uint64_t), + &data64, sizeof(data64)); + if (ret < 0) { + fprintf(stderr, "Could not update refcount table: %s\n", + strerror(-ret)); + goto fail; + } + + } + } } ret = 0; @@ -1204,7 +1251,7 @@ static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res, case QCOW2_CLUSTER_NORMAL: { - uint64_t offset = l2_entry & L2E_OFFSET_MASK; + uint64_t offset = (uint64_t)(l2_entry & L2E_OFFSET_MASK); if (flags & CHECK_FRAG_INFO) { res->bfi.allocated_clusters++; -- 1.9.3