| Message ID | 1491484536-22776-3-git-send-email-lidongchen@tencent.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 04/06 21:15, jemmy858585@gmail.com wrote: > From: Lidong Chen <lidongchen@tencent.com> > > BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default, > this maybe cause the qcow2 file size is bigger after migration. > This patch check each cluster, use blk_pwrite_zeroes for each > zero cluster. > > Signed-off-by: Lidong Chen <lidongchen@tencent.com> > --- > migration/block.c | 34 ++++++++++++++++++++++++++++++++-- > 1 file changed, 32 insertions(+), 2 deletions(-) > > diff --git a/migration/block.c b/migration/block.c > index 7734ff7..1fce9b9 100644 > --- a/migration/block.c > +++ b/migration/block.c > @@ -885,6 +885,10 @@ static int block_load(QEMUFile *f, void *opaque, int version_id) > int64_t total_sectors = 0; > int nr_sectors; > int ret; > + int i; > + int cluster_size; > + int64_t addr_offset; > + uint8_t *buf_offset; > > do { > addr = qemu_get_be64(f); > @@ -934,8 +938,34 @@ static int block_load(QEMUFile *f, void *opaque, int version_id) > } else { > buf = g_malloc(BLOCK_SIZE); > qemu_get_buffer(f, buf, BLOCK_SIZE); > - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf, > - nr_sectors * BDRV_SECTOR_SIZE, 0); > + > + cluster_size = bdrv_get_cluster_size(blk_bs(blk)); > + > + if (cluster_size > 0) { > + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) { Should we check that cluster_size < BLOCK_SIZE and (BLOCK_SIZE % cluster_size == 0)? Fam > + addr_offset = addr * BDRV_SECTOR_SIZE > + + i * cluster_size; > + buf_offset = buf + i * cluster_size; > + > + if (buffer_is_zero(buf_offset, cluster_size)) { > + ret = blk_pwrite_zeroes(blk, addr_offset, > + cluster_size, > + BDRV_REQ_MAY_UNMAP); > + } else { > + ret = blk_pwrite(blk, addr_offset, > + buf_offset, cluster_size, 0); > + } > + > + if (ret < 0) { > + g_free(buf); > + return ret; > + } > + } > + } else { > + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf, > + nr_sectors * BDRV_SECTOR_SIZE, 0); > + } > + > g_free(buf); > } > > -- > 1.8.3.1 >
On Fri, Apr 7, 2017 at 3:08 PM, Fam Zheng <famz@redhat.com> wrote: > On Thu, 04/06 21:15, jemmy858585@gmail.com wrote: >> From: Lidong Chen <lidongchen@tencent.com> >> >> BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default, >> this maybe cause the qcow2 file size is bigger after migration. >> This patch check each cluster, use blk_pwrite_zeroes for each >> zero cluster. >> >> Signed-off-by: Lidong Chen <lidongchen@tencent.com> >> --- >> migration/block.c | 34 ++++++++++++++++++++++++++++++++-- >> 1 file changed, 32 insertions(+), 2 deletions(-) >> >> diff --git a/migration/block.c b/migration/block.c >> index 7734ff7..1fce9b9 100644 >> --- a/migration/block.c >> +++ b/migration/block.c >> @@ -885,6 +885,10 @@ static int block_load(QEMUFile *f, void *opaque, int version_id) >> int64_t total_sectors = 0; >> int nr_sectors; >> int ret; >> + int i; >> + int cluster_size; >> + int64_t addr_offset; >> + uint8_t *buf_offset; >> >> do { >> addr = qemu_get_be64(f); >> @@ -934,8 +938,34 @@ static int block_load(QEMUFile *f, void *opaque, int version_id) >> } else { >> buf = g_malloc(BLOCK_SIZE); >> qemu_get_buffer(f, buf, BLOCK_SIZE); >> - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf, >> - nr_sectors * BDRV_SECTOR_SIZE, 0); >> + >> + cluster_size = bdrv_get_cluster_size(blk_bs(blk)); >> + >> + if (cluster_size > 0) { >> + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) { > > Should we check that cluster_size < BLOCK_SIZE and (BLOCK_SIZE % cluster_size == > 0)? I think this is necessary. Thanks. > > Fam > >> + addr_offset = addr * BDRV_SECTOR_SIZE >> + + i * cluster_size; >> + buf_offset = buf + i * cluster_size; >> + >> + if (buffer_is_zero(buf_offset, cluster_size)) { >> + ret = blk_pwrite_zeroes(blk, addr_offset, >> + cluster_size, >> + BDRV_REQ_MAY_UNMAP); >> + } else { >> + ret = blk_pwrite(blk, addr_offset, >> + buf_offset, cluster_size, 0); >> + } >> + >> + if (ret < 0) { >> + g_free(buf); >> + return ret; >> + } >> + } >> + } else { >> + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf, >> + nr_sectors * BDRV_SECTOR_SIZE, 0); >> + } >> + >> g_free(buf); >> } >> >> -- >> 1.8.3.1 >>
diff --git a/migration/block.c b/migration/block.c index 7734ff7..1fce9b9 100644 --- a/migration/block.c +++ b/migration/block.c @@ -885,6 +885,10 @@ static int block_load(QEMUFile *f, void *opaque, int version_id) int64_t total_sectors = 0; int nr_sectors; int ret; + int i; + int cluster_size; + int64_t addr_offset; + uint8_t *buf_offset; do { addr = qemu_get_be64(f); @@ -934,8 +938,34 @@ static int block_load(QEMUFile *f, void *opaque, int version_id) } else { buf = g_malloc(BLOCK_SIZE); qemu_get_buffer(f, buf, BLOCK_SIZE); - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf, - nr_sectors * BDRV_SECTOR_SIZE, 0); + + cluster_size = bdrv_get_cluster_size(blk_bs(blk)); + + if (cluster_size > 0) { + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) { + addr_offset = addr * BDRV_SECTOR_SIZE + + i * cluster_size; + buf_offset = buf + i * cluster_size; + + if (buffer_is_zero(buf_offset, cluster_size)) { + ret = blk_pwrite_zeroes(blk, addr_offset, + cluster_size, + BDRV_REQ_MAY_UNMAP); + } else { + ret = blk_pwrite(blk, addr_offset, + buf_offset, cluster_size, 0); + } + + if (ret < 0) { + g_free(buf); + return ret; + } + } + } else { + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf, + nr_sectors * BDRV_SECTOR_SIZE, 0); + } + g_free(buf); }