From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:51897) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UUz4L-00035a-Db for qemu-devel@nongnu.org; Wed, 24 Apr 2013 08:45:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UUz4E-0006yE-Fn for qemu-devel@nongnu.org; Wed, 24 Apr 2013 08:45:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:18860) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UUz4E-0006xK-85 for qemu-devel@nongnu.org; Wed, 24 Apr 2013 08:44:58 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r3OCivqv028286 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 24 Apr 2013 08:44:57 -0400 From: Fam Zheng Date: Wed, 24 Apr 2013 20:44:35 +0800 Message-Id: <1366807475-26350-7-git-send-email-famz@redhat.com> In-Reply-To: <1366807475-26350-1-git-send-email-famz@redhat.com> References: <1366807475-26350-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH v3 6/6] vmdk: add bdrv_co_write_zeroes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, Fam Zheng , stefanha@redhat.com Use special offset to write zeroes efficiently, when zeroed-grain GTE is available. If zero-write an allocated cluster, cluster is leaked because its offset pointer is overwritten by "0x1". Signed-off-by: Fam Zheng --- block/vmdk.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 63 insertions(+), 14 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 16e1417..90cb071 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -905,6 +905,13 @@ static int get_cluster_offset(BlockDriverState *bs, l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size; *cluster_offset = le32_to_cpu(l2_table[l2_index]); + if (m_data) { + m_data->valid = 1; + m_data->l1_index = l1_index; + m_data->l2_index = l2_index; + m_data->offset = *cluster_offset; + m_data->l2_offset = extent->l1_table[m_data->l1_index]; + } if (extent->has_zero_grain && *cluster_offset == VMDK_GTE_ZEROED) { zeroed = true; } @@ -1165,8 +1172,17 @@ static coroutine_fn int vmdk_co_read(BlockDriverState *bs, int64_t sector_num, return ret; } +/** + * vmdk_write: + * @zeroed: buf is ignored (data is zero), use zeroed_grain GTE feature + * if possible, otherwise return -ENOTSUP. + * @zero_dry_run: used for zeroed == true only, don't update L2 table, just + * + * Returns: error code with 0 for success. + */ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, - const uint8_t *buf, int nb_sectors) + const uint8_t *buf, int nb_sectors, + bool zeroed, bool zero_dry_run) { BDRVVmdkState *s = bs->opaque; VmdkExtent *extent = NULL; @@ -1212,7 +1228,7 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, &cluster_offset); } } - if (ret) { + if (ret == VMDK_ERROR) { return -EINVAL; } extent_begin_sector = extent->end_sector - extent->sectors; @@ -1222,17 +1238,34 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, if (n > nb_sectors) { n = nb_sectors; } - - ret = vmdk_write_extent(extent, - cluster_offset, index_in_cluster * 512, - buf, n, sector_num); - if (ret) { - return ret; - } - if (m_data.valid) { - /* update L2 tables */ - if (vmdk_L2update(extent, &m_data) == -1) { - return -EIO; + if (zeroed) { + /* Do zeroed write, buf is ignored */ + if (extent->has_zero_grain && + index_in_cluster == 0 && + n >= extent->cluster_sectors) { + n = extent->cluster_sectors; + if (!zero_dry_run) { + m_data.offset = cpu_to_le32(VMDK_GTE_ZEROED); + /* update L2 tables */ + if (vmdk_L2update(extent, &m_data) != VMDK_OK) { + return -EIO; + } + } + } else { + return -ENOTSUP; + } + } else { + ret = vmdk_write_extent(extent, + cluster_offset, index_in_cluster * 512, + buf, n, sector_num); + if (ret) { + return ret; + } + if (m_data.valid) { + /* update L2 tables */ + if (vmdk_L2update(extent, &m_data) != VMDK_OK) { + return -EIO; + } } } nb_sectors -= n; @@ -1258,7 +1291,22 @@ static coroutine_fn int vmdk_co_write(BlockDriverState *bs, int64_t sector_num, int ret; BDRVVmdkState *s = bs->opaque; qemu_co_mutex_lock(&s->lock); - ret = vmdk_write(bs, sector_num, buf, nb_sectors); + ret = vmdk_write(bs, sector_num, buf, nb_sectors, false, false); + qemu_co_mutex_unlock(&s->lock); + return ret; +} + +static int coroutine_fn vmdk_co_write_zeroes(BlockDriverState *bs, + int64_t sector_num, + int nb_sectors) +{ + int ret; + BDRVVmdkState *s = bs->opaque; + qemu_co_mutex_lock(&s->lock); + ret = vmdk_write(bs, sector_num, NULL, nb_sectors, true, true); + if (!ret) { + ret = vmdk_write(bs, sector_num, NULL, nb_sectors, true, false); + } qemu_co_mutex_unlock(&s->lock); return ret; } @@ -1738,6 +1786,7 @@ static BlockDriver bdrv_vmdk = { .bdrv_reopen_prepare = vmdk_reopen_prepare, .bdrv_read = vmdk_co_read, .bdrv_write = vmdk_co_write, + .bdrv_co_write_zeroes = vmdk_co_write_zeroes, .bdrv_close = vmdk_close, .bdrv_create = vmdk_create, .bdrv_co_flush_to_disk = vmdk_co_flush, -- 1.8.1.4