From f4bb4a2c3a5d628b07cd4219c4fe8b8ccfcbe963 Mon Sep 17 00:00:00 2001 Message-Id: In-Reply-To: <07146f8b79923c529fd93fa528e6fcbd6f571a02.1369658547.git.minovotn@redhat.com> References: <07146f8b79923c529fd93fa528e6fcbd6f571a02.1369658547.git.minovotn@redhat.com> From: Fam Zheng Date: Mon, 20 May 2013 03:37:02 +0200 Subject: [PATCH 47/47] vmdk: add bdrv_co_write_zeroes RH-Author: Fam Zheng Message-id: <1369021022-22728-48-git-send-email-famz@redhat.com> Patchwork-id: 51483 O-Subject: [PATCH RHEL-6.5 qemu-kvm v3 47/47] vmdk: add bdrv_co_write_zeroes Bugzilla: 960685 RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Jeffrey Cody RH-Acked-by: Kevin Wolf 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 Signed-off-by: Stefan Hajnoczi (cherry picked from commit cdeaf1f15909e2e8af38f45aea7cfa467a729c52) Signed-off-by: Fam Zheng --- block/vmdk.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 68 insertions(+), 18 deletions(-) Signed-off-by: Michal Novotny --- block/vmdk.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 68 insertions(+), 18 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index b2f45a8..308b82c 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -123,6 +123,7 @@ typedef struct VmdkMetaData { unsigned int l2_index; unsigned int l2_offset; int valid; + uint32_t *l2_cache_entry; } VmdkMetaData; typedef struct VmdkGrainMarker { @@ -826,6 +827,9 @@ static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data) return VMDK_ERROR; } } + if (m_data->l2_cache_entry) { + *m_data->l2_cache_entry = offset; + } return VMDK_OK; } @@ -896,6 +900,14 @@ 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 = l2_offset; + m_data->l2_cache_entry = &l2_table[l2_index]; + } if (extent->has_zero_grain && *cluster_offset == VMDK_GTE_ZEROED) { zeroed = true; } @@ -929,10 +941,6 @@ static int get_cluster_offset(BlockDriverState *bs, if (m_data) { m_data->offset = *cluster_offset; - m_data->l1_index = l1_index; - m_data->l2_index = l2_index; - m_data->l2_offset = l2_offset; - m_data->valid = 1; } } *cluster_offset <<= 9; @@ -1155,8 +1163,17 @@ 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; @@ -1202,7 +1219,7 @@ 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; @@ -1212,17 +1229,34 @@ 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 = 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; @@ -1248,7 +1282,22 @@ 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; } @@ -1726,6 +1775,7 @@ 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 = vmdk_co_flush, -- 1.7.11.7