Re: [Qemu-block] [Qemu-devel] [PATCH 0/5 v3] preparation for Parallels Disk xml driver

[klim]

On 01/12/2018 12:01 PM, Klim Kireev wrote:

ping

Parallels Desktop and Parallels Cloud Server uses images glued with the
bundle description in XML format. This series contains very basic
description of this XML files and makes preparations for actual
implementation to be followed.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>

Changelog:

v2:
PATCH 1/5: Fix some places noticed by Stefan Hajnoczi <stefa...@redhat.com>
PATCH 2/5: Rebase to upstream
PATCH 3/5: Fix includes

v3:
PATCH 1/5: Fix the place about GUID, add emails of the authors

[Qemu-block] [PATCH 4/5] block/parallels: replace some magic numbers

[Klim Kireev]

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 block/parallels.c | 5 +++--
 block/parallels.h | 2 ++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index f9a3b999ea..7a8e8b05a9 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -476,8 +476,9 @@ static int parallels_create(const char *filename, QemuOpts 
*opts, Error **errp)
 memcpy(header.magic, HEADER_MAGIC2, sizeof(header.magic));
 header.version = cpu_to_le32(HEADER_VERSION);
 /* don't care much about geometry, it is not used on image level */
-header.heads = cpu_to_le32(16);
-header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE / 16 / 32);
+header.heads = cpu_to_le32(HEADS_NUMBER);
+header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE
+   / HEADS_NUMBER / SEC_IN_CYL);
 header.tracks = cpu_to_le32(cl_size >> BDRV_SECTOR_BITS);
 header.bat_entries = cpu_to_le32(bat_entries);
 header.nb_sectors = cpu_to_le64(DIV_ROUND_UP(total_size, 
BDRV_SECTOR_SIZE));
diff --git a/block/parallels.h b/block/parallels.h
index 71183c0c8e..4b044079ef 100644
--- a/block/parallels.h
+++ b/block/parallels.h
@@ -34,6 +34,8 @@
 #include "qemu/coroutine.h"
 #include "qemu/typedefs.h"
 
+#define HEADS_NUMBER 16
+#define SEC_IN_CYL 32
 #define DEFAULT_CLUSTER_SIZE 1048576/* 1 MiB */
 
 /* always little-endian */
-- 
2.14.3

[Qemu-block] [PATCH 2/5] configure: add dependency

[Klim Kireev]

This dependency is required for adequate Parallels images support.
Typically the disk consists of several images which are glued by
XML disk descriptor. Also XML hides inside several important parameters
which are not available in the image header.

The patch also adds clause to checkpatch.pl to understand libxml2 types.

Signed-off-by: Denis V. Lunev <d...@openvz.org>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 block/Makefile.objs   |  2 ++
 configure | 27 +++
 scripts/checkpatch.pl |  1 +
 3 files changed, 30 insertions(+)

diff --git a/block/Makefile.objs b/block/Makefile.objs
index 6eaf78a046..a73387f1bf 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -47,3 +47,5 @@ block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
 dmg-bz2.o-libs := $(BZIP2_LIBS)
 qcow.o-libs:= -lz
 linux-aio.o-libs   := -laio
+parallels.o-cflags := $(LIBXML2_CFLAGS)
+parallels.o-libs   := $(LIBXML2_LIBS)
diff --git a/configure b/configure
index 6a040821c6..790fa635d1 100755
--- a/configure
+++ b/configure
@@ -435,6 +435,7 @@ tcmalloc="no"
 jemalloc="no"
 replication="yes"
 vxhs=""
+libxml2=""
 
 supported_cpu="no"
 supported_os="no"
@@ -1298,6 +1299,10 @@ for opt do
   ;;
   --enable-numa) numa="yes"
   ;;
+  --disable-libxml2) libxml2="no"
+  ;;
+  --enable-libxml2) libxml2="yes"
+  ;;
   --disable-tcmalloc) tcmalloc="no"
   ;;
   --enable-tcmalloc) tcmalloc="yes"
@@ -1573,6 +1578,7 @@ disabled with --disable-FEATURE, default is enabled if 
available:
   tpm TPM support
   libssh2 ssh block device support
   numalibnuma support
+  libxml2 for Parallels image format
   tcmalloctcmalloc support
   jemallocjemalloc support
   replication replication support
@@ -3747,6 +3753,20 @@ EOF
   fi
 fi
 
+##
+# libxml2 probe
+if test "$libxml2" != "no" ; then
+if $pkg_config --exists libxml-2.0; then
+libxml2="yes"
+libxml2_cflags=$($pkg_config --cflags libxml-2.0)
+libxml2_libs=$($pkg_config --libs libxml-2.0)
+else
+if test "$libxml2" = "yes"; then
+feature_not_found "libxml2" "Install libxml2 devel"
+fi
+libxml2="no"
+fi
+fi
 
 ##
 # glusterfs probe
@@ -5618,6 +5638,7 @@ echo "lzo support   $lzo"
 echo "snappy support$snappy"
 echo "bzip2 support $bzip2"
 echo "NUMA host support $numa"
+echo "libxml2   $libxml2"
 echo "tcmalloc support  $tcmalloc"
 echo "jemalloc support  $jemalloc"
 echo "avx2 optimization $avx2_opt"
@@ -6281,6 +6302,12 @@ if test "$have_rtnetlink" = "yes" ; then
   echo "CONFIG_RTNETLINK=y" >> $config_host_mak
 fi
 
+if test "$libxml2" = "yes" ; then
+  echo "CONFIG_LIBXML2=y" >> $config_host_mak
+  echo "LIBXML2_CFLAGS=$libxml2_cflags" >> $config_host_mak
+  echo "LIBXML2_LIBS=$libxml2_libs" >> $config_host_mak
+fi
+
 if test "$replication" = "yes" ; then
   echo "CONFIG_REPLICATION=y" >> $config_host_mak
 fi
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3dc27d9656..9bfe2b58e1 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -265,6 +265,7 @@ our @typeList = (
qr{${Ident}_handler_fn},
qr{target_(?:u)?long},
qr{hwaddr},
+   qr{xml${Ident}},
 );
 
 # This can be modified by sub possible.  Since it can be empty, be careful
-- 
2.14.3

[Qemu-block] [PATCH 3/5] block/parallels: move some structures into header

[Klim Kireev]

To implement xml format, some defines and structures
from parallels.c are required.

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 block/parallels.c | 53 +-
 block/parallels.h | 86 +++
 2 files changed, 87 insertions(+), 52 deletions(-)
 create mode 100644 block/parallels.h

diff --git a/block/parallels.c b/block/parallels.c
index 9545761f49..f9a3b999ea 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -36,6 +36,7 @@
 #include "qemu/bswap.h"
 #include "qemu/bitmap.h"
 #include "migration/blocker.h"
+#include "parallels.h"
 
 /**/
 
@@ -45,30 +46,6 @@
 #define HEADER_INUSE_MAGIC  (0x746F6E59)
 #define MAX_PARALLELS_IMAGE_FACTOR (1ull << 32)
 
-#define DEFAULT_CLUSTER_SIZE 1048576/* 1 MiB */
-
-
-// always little-endian
-typedef struct ParallelsHeader {
-char magic[16]; // "WithoutFreeSpace"
-uint32_t version;
-uint32_t heads;
-uint32_t cylinders;
-uint32_t tracks;
-uint32_t bat_entries;
-uint64_t nb_sectors;
-uint32_t inuse;
-uint32_t data_off;
-char padding[12];
-} QEMU_PACKED ParallelsHeader;
-
-
-typedef enum ParallelsPreallocMode {
-PRL_PREALLOC_MODE_FALLOCATE = 0,
-PRL_PREALLOC_MODE_TRUNCATE = 1,
-PRL_PREALLOC_MODE__MAX = 2,
-} ParallelsPreallocMode;
-
 static QEnumLookup prealloc_mode_lookup = {
 .array = (const char *const[]) {
 "falloc",
@@ -77,34 +54,6 @@ static QEnumLookup prealloc_mode_lookup = {
 .size = PRL_PREALLOC_MODE__MAX
 };
 
-typedef struct BDRVParallelsState {
-/** Locking is conservative, the lock protects
- *   - image file extending (truncate, fallocate)
- *   - any access to block allocation table
- */
-CoMutex lock;
-
-ParallelsHeader *header;
-uint32_t header_size;
-bool header_unclean;
-
-unsigned long *bat_dirty_bmap;
-unsigned int  bat_dirty_block;
-
-uint32_t *bat_bitmap;
-unsigned int bat_size;
-
-int64_t  data_end;
-uint64_t prealloc_size;
-ParallelsPreallocMode prealloc_mode;
-
-unsigned int tracks;
-
-unsigned int off_multiplier;
-Error *migration_blocker;
-} BDRVParallelsState;
-
-
 #define PARALLELS_OPT_PREALLOC_MODE "prealloc-mode"
 #define PARALLELS_OPT_PREALLOC_SIZE "prealloc-size"
 
diff --git a/block/parallels.h b/block/parallels.h
new file mode 100644
index 00..71183c0c8e
--- /dev/null
+++ b/block/parallels.h
@@ -0,0 +1,86 @@
+/*
+* Block driver for Parallels disk image format
+*
+* Copyright (c) 2015-2017 Virtuozzo, Inc.
+* Authors:
+* 2016-2017 Klim S. Kireev <klim.kir...@virtuozzo.com>
+* 2015 Denis V. Lunev <d...@openvz.org>
+*
+* This code was originally based on comparing different disk images created
+* by Parallels. Currently it is based on opened OpenVZ sources
+* available at
+* https://github.com/OpenVZ/ploop
+*
+* Permission is hereby granted, free of charge, to any person obtaining a copy
+* of this software and associated documentation files (the "Software"), to deal
+* in the Software without restriction, including without limitation the rights
+* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+* copies of the Software, and to permit persons to whom the Software is
+* furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included in
+* all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+* THE SOFTWARE.
+*/
+#ifndef BLOCK_PARALLELS_H
+#define BLOCK_PARALLELS_H
+#include "qemu/coroutine.h"
+#include "qemu/typedefs.h"
+
+#define DEFAULT_CLUSTER_SIZE 1048576/* 1 MiB */
+
+/* always little-endian */
+typedef struct ParallelsHeader {
+char magic[16]; /* "WithoutFreeSpace" */
+uint32_t version;
+uint32_t heads;
+uint32_t cylinders;
+uint32_t tracks;
+uint32_t bat_entries;
+uint64_t nb_sectors;
+uint32_t inuse;
+uint32_t data_off;
+char padding[12];
+} QEMU_PACKED ParallelsHeader;
+
+typedef enum ParallelsPreallocMode {
+PRL_PREALLOC_MODE_FALLOCATE = 0,
+PRL_PREAL

[Qemu-block] [PATCH 1/5] docs/interop/prl-xml: description of Parallels Disk format

[Klim Kireev]

This patch adds main information about Parallels Disk
format, which consists of DiskDescriptor.xml and other files.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 docs/interop/prl-xml.txt | 158 +++
 1 file changed, 158 insertions(+)
 create mode 100644 docs/interop/prl-xml.txt

diff --git a/docs/interop/prl-xml.txt b/docs/interop/prl-xml.txt
new file mode 100644
index 00..7031f8752c
--- /dev/null
+++ b/docs/interop/prl-xml.txt
@@ -0,0 +1,158 @@
+= License =
+
+Copyright (c) 2015-2017, Virtuozzo, Inc.
+Authors:
+2015 Denis Lunev <d...@openvz.org>
+2015 Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
+2016-2017 Klim Kireev <klim.kir...@virtuozzo.com>
+2016-2017 Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
+
+This work is licensed under the terms of the GNU GPL, version 2 or later.
+See the COPYING file in the top-level directory.
+
+This specification contains minimal information about Parallels Disk Format,
+which is enough to proper work with QEMU. Nevertheless, Parallels Cloud Server
+and Parallels Desktop are able to add some unspecified nodes to xml and use
+them, but they are for internal work and don't affect functionality. Also it
+uses auxiliary xml "Snapshot.xml", which allows to store optional snapshot
+information, but it doesn't influence open/read/write functionality. QEMU and
+other software should not use fields not covered in this document and
+Snapshot.xml file and must leave them as is.
+
+= Parallels Disk Format =
+
+Parallels disk consists of two parts: the set of snapshots and the disk
+descriptor file, which stores information about all files and snapshots.
+
+== Definitions ==
+Snapshot   a record of the contents captured at a particular time,
+   capable of storing current state. A snapshot has UUID and
+   parent UUID.
+
+ Snapshot imagean overlay representing the difference between this
+   snapshot and some earlier snapshot.
+
+Overlayan image storing the different sectors between two captured
+   states.
+
+   Root image  snapshot image with no parent, the root of snapshot tree.
+
+Storagethe backing storage for a subset of the virtual disk. When
+   there is more than one storage in a Parallels disk then that
+   is referred to as a split image. In this case every storage
+   covers specific address space area of the disk and has its
+   particular root image. Split images are not considered here
+   and are not supported. Each storage consists of disk
+   parameters and a list of images. The list of images always
+   contains a root image and may also contain overlays. The
+   root image can be an expandable Parallels image file or
+   plain. Overlays must be expandable.
+
+  Description  DiskDescriptor.xml stores information about disk parameters,
+ file  snapshots, storages.
+
+ Top   The overlay between actual state and some previous snapshot.
+   SnapshotIt is not a snapshot in the classical sense because it
+   serves as the active image that the guest writes to.
+
+Sector a 512-byte data chunk.
+
+== Description file ==
+All information is placed in a single XML element Parallels_disk_image.
+The element has only one attribute "Version", that must be 1.0.
+Schema of DiskDescriptor.xml:
+
+
+
+...
+
+
+...
+
+
+...
+
+
+
+== Disk_Parameters element ==
+The Disk_Parameters element describes the physical layout of the virtual disk
+and some general settings.
+
+The Disk_Parameters element MUST contain the following child elements:
+* Disk_size - number of sectors in the disk,
+  desired size of the disk.
+* Cylinders - number of the disk cylinders.
+* Heads - number of the disk heads.
+* Sectors   - number of the disk sectors per cylinder
+  (sector size is 512 bytes)
+  Limitation: Product of the Heads, Sectors and Cylinders
+  values MUST be equal to the value of the Disk_size parameter.
+* Padding   - must be 0. Parallels Cloud Server and Parallels Desktop may
+  use padding set to 1, however this case is not covered
+  by this spec, QEMU and other software should not open
+  such disks and should not create them.
+
+== StorageData element ==
+This element of the file de

[Qemu-block] [PATCH 0/5 v3] preparation for Parallels Disk xml driver

[Klim Kireev]

Parallels Desktop and Parallels Cloud Server uses images glued with the
bundle description in XML format. This series contains very basic
description of this XML files and makes preparations for actual
implementation to be followed.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>

Changelog:

v2:
PATCH 1/5: Fix some places noticed by Stefan Hajnoczi <stefa...@redhat.com>
PATCH 2/5: Rebase to upstream
PATCH 3/5: Fix includes

v3:
PATCH 1/5: Fix the place about GUID, add emails of the authors

[Qemu-block] [PATCH 5/5] block/parallels: add backing support to readv/writev

[Klim Kireev]

From: Edgar Kaziakhmedov 

Since parallels format supports backing files, refine
readv/writev (allocate_clusters) to redirect read/write requests
to a backing file (if cluster is not available in the current bs).

Signed-off-by: Edgar Kaziakhmedov 
Signed-off-by: Vladimir Sementsov-Ogievskiy 
Signed-off-by: Denis V. Lunev 
CC: Stefan Hajnoczi 
---
 block/parallels.c | 50 --
 1 file changed, 44 insertions(+), 6 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index 7a8e8b05a9..d3802085e3 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -142,6 +142,7 @@ static int64_t block_status(BDRVParallelsState *s, int64_t 
sector_num,
 static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num,
  int nb_sectors, int *pnum)
 {
+int ret;
 BDRVParallelsState *s = bs->opaque;
 int64_t pos, space, idx, to_allocate, i, len;
 
@@ -170,7 +171,6 @@ static int64_t allocate_clusters(BlockDriverState *bs, 
int64_t sector_num,
 return len;
 }
 if (s->data_end + space > (len >> BDRV_SECTOR_BITS)) {
-int ret;
 space += s->prealloc_size;
 if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) {
 ret = bdrv_pwrite_zeroes(bs->file,
@@ -186,6 +186,37 @@ static int64_t allocate_clusters(BlockDriverState *bs, 
int64_t sector_num,
 }
 }
 
+/* Try to read from backing to fill empty clusters
+ * FIXME: 1. previous write_zeroes may be redundant
+ *2. most of data we read from backing will be rewritten by
+ *   parallels_co_writev. On aligned-to-cluster write we do not 
need
+ *   this read at all.
+ *3. it would be good to combine write of data from backing and new
+ *   data into one write call */
+if (bs->backing) {
+int64_t nb_cow_sectors = to_allocate * s->tracks;
+int64_t nb_cow_bytes = nb_cow_sectors << BDRV_SECTOR_BITS;
+QEMUIOVector qiov;
+struct iovec iov = {
+.iov_len = nb_cow_bytes,
+.iov_base = qemu_blockalign(bs, nb_cow_bytes)
+};
+qemu_iovec_init_external(, , 1);
+
+ret = bdrv_co_readv(bs->backing, idx * s->tracks, nb_cow_sectors,
+);
+if (ret < 0) {
+qemu_vfree(iov.iov_base);
+return ret;
+}
+
+ret = bdrv_co_writev(bs->file, s->data_end, nb_cow_sectors, );
+qemu_vfree(iov.iov_base);
+if (ret < 0) {
+return ret;
+}
+}
+
 for (i = 0; i < to_allocate; i++) {
 s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier);
 s->data_end += s->tracks;
@@ -309,12 +340,19 @@ static coroutine_fn int 
parallels_co_readv(BlockDriverState *bs,
 
 nbytes = n << BDRV_SECTOR_BITS;
 
+qemu_iovec_reset(_qiov);
+qemu_iovec_concat(_qiov, qiov, bytes_done, nbytes);
+
 if (position < 0) {
-qemu_iovec_memset(qiov, bytes_done, 0, nbytes);
+if (bs->backing) {
+ret = bdrv_co_readv(bs->backing, sector_num, n, _qiov);
+if (ret < 0) {
+break;
+}
+} else {
+qemu_iovec_memset(_qiov, 0, 0, nbytes);
+}
 } else {
-qemu_iovec_reset(_qiov);
-qemu_iovec_concat(_qiov, qiov, bytes_done, nbytes);
-
 ret = bdrv_co_readv(bs->file, position, n, _qiov);
 if (ret < 0) {
 break;
@@ -748,7 +786,7 @@ static BlockDriver bdrv_parallels = {
 .bdrv_co_flush_to_os  = parallels_co_flush_to_os,
 .bdrv_co_readv  = parallels_co_readv,
 .bdrv_co_writev = parallels_co_writev,
-
+.supports_backing = true,
 .bdrv_create= parallels_create,
 .bdrv_check = parallels_check,
 .create_opts= _create_opts,
-- 
2.14.3

[Qemu-block] [PATCH 0/5 v2] preparation for Parallels Disk xml driver

[Klim Kireev]

Parallels Desktop and Parallels Cloud Server uses images glued with the
bundle description in XML format. This series contains very basic
description of this XML files and makes preparations for actual
implementation to be followed.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>

Changelog:

v2:
PATCH 1/5: Fix some places noticed by Stefan Hajnoczi <stefa...@redhat.com>
PATCH 2/5: Rebase to upstream
PATCH 3/5: Fix includes

[Qemu-block] [PATCH 3/5] block/parallels: move some structures into header

[Klim Kireev]

To implement xml format, some defines and structures
from parallels.c are required.

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 block/parallels.c | 53 +-
 block/parallels.h | 86 +++
 2 files changed, 87 insertions(+), 52 deletions(-)
 create mode 100644 block/parallels.h

diff --git a/block/parallels.c b/block/parallels.c
index 9545761f49..f9a3b999ea 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -36,6 +36,7 @@
 #include "qemu/bswap.h"
 #include "qemu/bitmap.h"
 #include "migration/blocker.h"
+#include "parallels.h"
 
 /**/
 
@@ -45,30 +46,6 @@
 #define HEADER_INUSE_MAGIC  (0x746F6E59)
 #define MAX_PARALLELS_IMAGE_FACTOR (1ull << 32)
 
-#define DEFAULT_CLUSTER_SIZE 1048576/* 1 MiB */
-
-
-// always little-endian
-typedef struct ParallelsHeader {
-char magic[16]; // "WithoutFreeSpace"
-uint32_t version;
-uint32_t heads;
-uint32_t cylinders;
-uint32_t tracks;
-uint32_t bat_entries;
-uint64_t nb_sectors;
-uint32_t inuse;
-uint32_t data_off;
-char padding[12];
-} QEMU_PACKED ParallelsHeader;
-
-
-typedef enum ParallelsPreallocMode {
-PRL_PREALLOC_MODE_FALLOCATE = 0,
-PRL_PREALLOC_MODE_TRUNCATE = 1,
-PRL_PREALLOC_MODE__MAX = 2,
-} ParallelsPreallocMode;
-
 static QEnumLookup prealloc_mode_lookup = {
 .array = (const char *const[]) {
 "falloc",
@@ -77,34 +54,6 @@ static QEnumLookup prealloc_mode_lookup = {
 .size = PRL_PREALLOC_MODE__MAX
 };
 
-typedef struct BDRVParallelsState {
-/** Locking is conservative, the lock protects
- *   - image file extending (truncate, fallocate)
- *   - any access to block allocation table
- */
-CoMutex lock;
-
-ParallelsHeader *header;
-uint32_t header_size;
-bool header_unclean;
-
-unsigned long *bat_dirty_bmap;
-unsigned int  bat_dirty_block;
-
-uint32_t *bat_bitmap;
-unsigned int bat_size;
-
-int64_t  data_end;
-uint64_t prealloc_size;
-ParallelsPreallocMode prealloc_mode;
-
-unsigned int tracks;
-
-unsigned int off_multiplier;
-Error *migration_blocker;
-} BDRVParallelsState;
-
-
 #define PARALLELS_OPT_PREALLOC_MODE "prealloc-mode"
 #define PARALLELS_OPT_PREALLOC_SIZE "prealloc-size"
 
diff --git a/block/parallels.h b/block/parallels.h
new file mode 100644
index 00..71183c0c8e
--- /dev/null
+++ b/block/parallels.h
@@ -0,0 +1,86 @@
+/*
+* Block driver for Parallels disk image format
+*
+* Copyright (c) 2015-2017 Virtuozzo, Inc.
+* Authors:
+* 2016-2017 Klim S. Kireev <klim.kir...@virtuozzo.com>
+* 2015 Denis V. Lunev <d...@openvz.org>
+*
+* This code was originally based on comparing different disk images created
+* by Parallels. Currently it is based on opened OpenVZ sources
+* available at
+* https://github.com/OpenVZ/ploop
+*
+* Permission is hereby granted, free of charge, to any person obtaining a copy
+* of this software and associated documentation files (the "Software"), to deal
+* in the Software without restriction, including without limitation the rights
+* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+* copies of the Software, and to permit persons to whom the Software is
+* furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included in
+* all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+* THE SOFTWARE.
+*/
+#ifndef BLOCK_PARALLELS_H
+#define BLOCK_PARALLELS_H
+#include "qemu/coroutine.h"
+#include "qemu/typedefs.h"
+
+#define DEFAULT_CLUSTER_SIZE 1048576/* 1 MiB */
+
+/* always little-endian */
+typedef struct ParallelsHeader {
+char magic[16]; /* "WithoutFreeSpace" */
+uint32_t version;
+uint32_t heads;
+uint32_t cylinders;
+uint32_t tracks;
+uint32_t bat_entries;
+uint64_t nb_sectors;
+uint32_t inuse;
+uint32_t data_off;
+char padding[12];
+} QEMU_PACKED ParallelsHeader;
+
+typedef enum ParallelsPreallocMode {
+PRL_PREALLOC_MODE_FALLOCATE = 0,
+PRL_PREAL

[Qemu-block] [PATCH 2/5] configure: add dependency

[Klim Kireev]

This dependency is required for adequate Parallels images support.
Typically the disk consists of several images which are glued by
XML disk descriptor. Also XML hides inside several important parameters
which are not available in the image header.

The patch also adds clause to checkpatch.pl to understand libxml2 types.

Signed-off-by: Denis V. Lunev <d...@openvz.org>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 block/Makefile.objs   |  2 ++
 configure | 27 +++
 scripts/checkpatch.pl |  1 +
 3 files changed, 30 insertions(+)

diff --git a/block/Makefile.objs b/block/Makefile.objs
index 6eaf78a046..a73387f1bf 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -47,3 +47,5 @@ block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
 dmg-bz2.o-libs := $(BZIP2_LIBS)
 qcow.o-libs:= -lz
 linux-aio.o-libs   := -laio
+parallels.o-cflags := $(LIBXML2_CFLAGS)
+parallels.o-libs   := $(LIBXML2_LIBS)
diff --git a/configure b/configure
index 6a040821c6..790fa635d1 100755
--- a/configure
+++ b/configure
@@ -435,6 +435,7 @@ tcmalloc="no"
 jemalloc="no"
 replication="yes"
 vxhs=""
+libxml2=""
 
 supported_cpu="no"
 supported_os="no"
@@ -1298,6 +1299,10 @@ for opt do
   ;;
   --enable-numa) numa="yes"
   ;;
+  --disable-libxml2) libxml2="no"
+  ;;
+  --enable-libxml2) libxml2="yes"
+  ;;
   --disable-tcmalloc) tcmalloc="no"
   ;;
   --enable-tcmalloc) tcmalloc="yes"
@@ -1573,6 +1578,7 @@ disabled with --disable-FEATURE, default is enabled if 
available:
   tpm TPM support
   libssh2 ssh block device support
   numalibnuma support
+  libxml2 for Parallels image format
   tcmalloctcmalloc support
   jemallocjemalloc support
   replication replication support
@@ -3747,6 +3753,20 @@ EOF
   fi
 fi
 
+##
+# libxml2 probe
+if test "$libxml2" != "no" ; then
+if $pkg_config --exists libxml-2.0; then
+libxml2="yes"
+libxml2_cflags=$($pkg_config --cflags libxml-2.0)
+libxml2_libs=$($pkg_config --libs libxml-2.0)
+else
+if test "$libxml2" = "yes"; then
+feature_not_found "libxml2" "Install libxml2 devel"
+fi
+libxml2="no"
+fi
+fi
 
 ##
 # glusterfs probe
@@ -5618,6 +5638,7 @@ echo "lzo support   $lzo"
 echo "snappy support$snappy"
 echo "bzip2 support $bzip2"
 echo "NUMA host support $numa"
+echo "libxml2   $libxml2"
 echo "tcmalloc support  $tcmalloc"
 echo "jemalloc support  $jemalloc"
 echo "avx2 optimization $avx2_opt"
@@ -6281,6 +6302,12 @@ if test "$have_rtnetlink" = "yes" ; then
   echo "CONFIG_RTNETLINK=y" >> $config_host_mak
 fi
 
+if test "$libxml2" = "yes" ; then
+  echo "CONFIG_LIBXML2=y" >> $config_host_mak
+  echo "LIBXML2_CFLAGS=$libxml2_cflags" >> $config_host_mak
+  echo "LIBXML2_LIBS=$libxml2_libs" >> $config_host_mak
+fi
+
 if test "$replication" = "yes" ; then
   echo "CONFIG_REPLICATION=y" >> $config_host_mak
 fi
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3dc27d9656..9bfe2b58e1 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -265,6 +265,7 @@ our @typeList = (
qr{${Ident}_handler_fn},
qr{target_(?:u)?long},
qr{hwaddr},
+   qr{xml${Ident}},
 );
 
 # This can be modified by sub possible.  Since it can be empty, be careful
-- 
2.14.3

[Qemu-block] [PATCH 1/5] docs/interop/prl-xml: description of Parallels Disk format

[Klim Kireev]

This patch adds main information about Parallels Disk
format, which consists of DiskDescriptor.xml and other files.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 docs/interop/prl-xml.txt | 156 +++
 1 file changed, 156 insertions(+)
 create mode 100644 docs/interop/prl-xml.txt

diff --git a/docs/interop/prl-xml.txt b/docs/interop/prl-xml.txt
new file mode 100644
index 00..57bffc67ae
--- /dev/null
+++ b/docs/interop/prl-xml.txt
@@ -0,0 +1,156 @@
+= License =
+
+Copyright (c) 2015-2017, Virtuozzo, Inc.
+Authors:
+2015 Denis Lunev
+2015 Vladimir Sementsov-Ogievskiy
+2016-2017 Klim Kireev
+2016-2017 Edgar Kaziakhmedov
+
+This work is licensed under the terms of the GNU GPL, version 2 or later.
+See the COPYING file in the top-level directory.
+
+This specification contains minimal information about Parallels Disk Format,
+which is enough to proper work with QEMU. Nevertheless, Parallels Cloud Server
+and Parallels Desktop are able to add some unspecified nodes to xml and use
+them, but they are for internal work and don't affect functionality. Also it
+uses auxiliary xml "Snapshot.xml", which allows to store optional snapshot
+information, but it doesn't influence open/read/write functionality. QEMU and
+other software should not use fields not covered in this document and
+Snapshot.xml file and must leave them as is.
+
+= Parallels Disk Format =
+
+Parallels disk consists of two parts: the set of snapshots and the disk
+descriptor file, which stores information about all files and snapshots.
+
+== Definitions ==
+Snapshot   a record of the contents captured at a particular time,
+   capable of storing current state. A snapshot has UUID and
+   parent UUID.
+
+ Snapshot imagean overlay representing the difference between this
+   snapshot and some earlier snapshot.
+
+Overlayan image storing the different sectors between two captured
+   states.
+
+   Root image  snapshot image with no parent, the root of snapshot tree.
+
+Storagethe backing storage for a subset of the virtual disk. When
+   there is more than one storage in a Parallels disk then that
+   is referred to as a split image. In this case every storage
+   covers specific address space area of the disk and has its
+   particular root image. Split images are not considered here
+   and are not supported. Each storage consists of disk
+   parameters and a list of images. The list of images always
+   contains a root image and may also contain overlays. The
+   root image can be an expandable Parallels image file or
+   plain. Overlays must be expandable.
+
+  Description  DiskDescriptor.xml stores information about disk parameters,
+ file  snapshots, storages.
+
+ Top   The overlay between actual state and some previous snapshot.
+   SnapshotIt is not a snapshot in the classical sense because it
+   serves as the active image that the guest writes to.
+
+Sector a 512-byte data chunk.
+
+== Description file ==
+All information is placed in a single XML element Parallels_disk_image.
+The element has only one attribute "Version", that must be 1.0.
+Schema of DiskDescriptor.xml:
+
+
+
+...
+
+
+...
+
+
+...
+
+
+
+== Disk_Parameters element ==
+The Disk_Parameters element describes the physical layout of the virtual disk
+and some general settings.
+
+The Disk_Parameters element MUST contain the following child elements:
+* Disk_size - number of sectors in the disk,
+  desired size of the disk.
+* Cylinders - number of the disk cylinders.
+* Heads - number of the disk heads.
+* Sectors   - number of the disk sectors per cylinder
+  (sector size is 512 bytes)
+  Limitation: Product of the Heads, Sectors and Cylinders
+  values MUST be equal to the value of the Disk_size parameter.
+* Padding   - must be 0. Parallels Cloud Server and Parallels Desktop may
+  use padding set to 1, however this case is not covered
+  by this spec, QEMU and other software should not open
+  such disks and should not create them.
+
+== StorageData element ==
+This element of the file describes the root image and all snapshot images.
+
+The StorageData element consists of the Storage child element, as shown below:
+
+

[Qemu-block] [PATCH 5/5] block/parallels: add backing support to readv/writev

[Klim Kireev]

From: Edgar Kaziakhmedov 

Since parallels format supports backing files, refine
readv/writev (allocate_clusters) to redirect read/write requests
to a backing file (if cluster is not available in the current bs).

Signed-off-by: Edgar Kaziakhmedov 
Signed-off-by: Vladimir Sementsov-Ogievskiy 
Signed-off-by: Denis V. Lunev 
CC: Stefan Hajnoczi 
---
 block/parallels.c | 50 --
 1 file changed, 44 insertions(+), 6 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index 7a8e8b05a9..d3802085e3 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -142,6 +142,7 @@ static int64_t block_status(BDRVParallelsState *s, int64_t 
sector_num,
 static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num,
  int nb_sectors, int *pnum)
 {
+int ret;
 BDRVParallelsState *s = bs->opaque;
 int64_t pos, space, idx, to_allocate, i, len;
 
@@ -170,7 +171,6 @@ static int64_t allocate_clusters(BlockDriverState *bs, 
int64_t sector_num,
 return len;
 }
 if (s->data_end + space > (len >> BDRV_SECTOR_BITS)) {
-int ret;
 space += s->prealloc_size;
 if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) {
 ret = bdrv_pwrite_zeroes(bs->file,
@@ -186,6 +186,37 @@ static int64_t allocate_clusters(BlockDriverState *bs, 
int64_t sector_num,
 }
 }
 
+/* Try to read from backing to fill empty clusters
+ * FIXME: 1. previous write_zeroes may be redundant
+ *2. most of data we read from backing will be rewritten by
+ *   parallels_co_writev. On aligned-to-cluster write we do not 
need
+ *   this read at all.
+ *3. it would be good to combine write of data from backing and new
+ *   data into one write call */
+if (bs->backing) {
+int64_t nb_cow_sectors = to_allocate * s->tracks;
+int64_t nb_cow_bytes = nb_cow_sectors << BDRV_SECTOR_BITS;
+QEMUIOVector qiov;
+struct iovec iov = {
+.iov_len = nb_cow_bytes,
+.iov_base = qemu_blockalign(bs, nb_cow_bytes)
+};
+qemu_iovec_init_external(, , 1);
+
+ret = bdrv_co_readv(bs->backing, idx * s->tracks, nb_cow_sectors,
+);
+if (ret < 0) {
+qemu_vfree(iov.iov_base);
+return ret;
+}
+
+ret = bdrv_co_writev(bs->file, s->data_end, nb_cow_sectors, );
+qemu_vfree(iov.iov_base);
+if (ret < 0) {
+return ret;
+}
+}
+
 for (i = 0; i < to_allocate; i++) {
 s->bat_bitmap[idx + i] = cpu_to_le32(s->data_end / s->off_multiplier);
 s->data_end += s->tracks;
@@ -309,12 +340,19 @@ static coroutine_fn int 
parallels_co_readv(BlockDriverState *bs,
 
 nbytes = n << BDRV_SECTOR_BITS;
 
+qemu_iovec_reset(_qiov);
+qemu_iovec_concat(_qiov, qiov, bytes_done, nbytes);
+
 if (position < 0) {
-qemu_iovec_memset(qiov, bytes_done, 0, nbytes);
+if (bs->backing) {
+ret = bdrv_co_readv(bs->backing, sector_num, n, _qiov);
+if (ret < 0) {
+break;
+}
+} else {
+qemu_iovec_memset(_qiov, 0, 0, nbytes);
+}
 } else {
-qemu_iovec_reset(_qiov);
-qemu_iovec_concat(_qiov, qiov, bytes_done, nbytes);
-
 ret = bdrv_co_readv(bs->file, position, n, _qiov);
 if (ret < 0) {
 break;
@@ -748,7 +786,7 @@ static BlockDriver bdrv_parallels = {
 .bdrv_co_flush_to_os  = parallels_co_flush_to_os,
 .bdrv_co_readv  = parallels_co_readv,
 .bdrv_co_writev = parallels_co_writev,
-
+.supports_backing = true,
 .bdrv_create= parallels_create,
 .bdrv_check = parallels_check,
 .create_opts= _create_opts,
-- 
2.14.3

[Qemu-block] [PATCH 4/5] block/parallels: replace some magic numbers

[Klim Kireev]

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
 block/parallels.c | 5 +++--
 block/parallels.h | 2 ++
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/block/parallels.c b/block/parallels.c
index f9a3b999ea..7a8e8b05a9 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -476,8 +476,9 @@ static int parallels_create(const char *filename, QemuOpts 
*opts, Error **errp)
 memcpy(header.magic, HEADER_MAGIC2, sizeof(header.magic));
 header.version = cpu_to_le32(HEADER_VERSION);
 /* don't care much about geometry, it is not used on image level */
-header.heads = cpu_to_le32(16);
-header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE / 16 / 32);
+header.heads = cpu_to_le32(HEADS_NUMBER);
+header.cylinders = cpu_to_le32(total_size / BDRV_SECTOR_SIZE
+   / HEADS_NUMBER / SEC_IN_CYL);
 header.tracks = cpu_to_le32(cl_size >> BDRV_SECTOR_BITS);
 header.bat_entries = cpu_to_le32(bat_entries);
 header.nb_sectors = cpu_to_le64(DIV_ROUND_UP(total_size, 
BDRV_SECTOR_SIZE));
diff --git a/block/parallels.h b/block/parallels.h
index 71183c0c8e..4b044079ef 100644
--- a/block/parallels.h
+++ b/block/parallels.h
@@ -34,6 +34,8 @@
 #include "qemu/coroutine.h"
 #include "qemu/typedefs.h"
 
+#define HEADS_NUMBER 16
+#define SEC_IN_CYL 32
 #define DEFAULT_CLUSTER_SIZE 1048576/* 1 MiB */
 
 /* always little-endian */
-- 
2.14.3

Re: [Qemu-block] [PATCH 1/5] docs/interop/prl-xml: description of Parallels Disk format

[klim]

On 01/04/2018 02:34 PM, Stefan Hajnoczi wrote:

On Mon, Dec 18, 2017 at 02:09:07PM +0300, Denis V. Lunev wrote:

From: Klim Kireev <klim.kir...@virtuozzo.com>

This patch adds main information about Parallels Disk
format, which consists of DiskDescriptor.xml and other files.

Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
  docs/interop/prl-xml.txt | 155 +++
  1 file changed, 155 insertions(+)
  create mode 100644 docs/interop/prl-xml.txt

diff --git a/docs/interop/prl-xml.txt b/docs/interop/prl-xml.txt
new file mode 100644
index 000..8ccb91a
--- /dev/null
+++ b/docs/interop/prl-xml.txt
@@ -0,0 +1,155 @@
+= License =
+
+Copyright (c) 2015 Denis Lunev
+Copyright (c) 2015 Vladimir Sementsov-Ogievskiy
+Copyright (c) 2016-2017 Klim Kireev
+Copyright (c) 2016-2017 Edgar Kaziakhmedov
+
+This work is licensed under the terms of the GNU GPL, version 2 or later.
+See the COPYING file in the top-level directory.
+
+This specification contains minimal information about Parallels Disk Format,
+which is enough to proper work with QEMU. Nevertheless, Parallels Cloud Server
+and Parallels Desktop are able to add some unspecified nodes to xml and use
+them, but they are for internal work and don't affect functionality. Also it
+uses auxiliary xml "Snapshot.xml", which allows to store optional snapshot
+information, but it doesn't influence open/read/write functionality. QEMU and
+other software should not use unspecified here fields and Snapshot.xml file

s/unspecified here fields/fields not covered in this document/


+and must leave them as is.
+
+= Parallels Disk Format =
+
+Parallels disk consists of two parts: the set of snapshots and the disk
+descriptor file, which stores information about all files and snapshots.
+
+== Definitions ==
+Snapshot   a record of the contents captured at a particular time,
+   capable of storing current state. A snapshot has UUID and
+   parent UUID.
+
+ Snapshot imagean overlay representing the difference between this
+   snapshot and some earlier snapshot
+
+Overlayan image storing the different sectors between two captured
+   states.
+
+   Root image  snapshot image without parent, the root of snapshot tree.

s/without parent/with no parent/


+
+Storagea special conception of data, which consists of disk
+   parameters and a list of images. One of this image is root,
+   others are overlays. Images must be expandable (parallels
+   image file), however root image could be expandable or
+   plain. There may be more then one storage in the Parallels

s/then/than/


+   disk and it is defined as a split image.

I was having trouble understanding this paragraph.  At this point I can
begin to see that split images consist of multiple storages.  That makes
the concept of storage clearer.

Perhaps rephrase this paragraph as:

the backing storage for a subset of the virtual disk.  When there is
more than one storage in a Parallels disk then that is referred to as a
split image.  Each storage consists of disk parameters and a list of
images.  The list of images always contains a root image and may also
contain overlays.  The root image can be an expandable Parallels image
file or plain.  Overlays must be expandable.


+   In this case every storage covers specific address
+   space area of the disk and has its particular root image.
+   Split images are not considered here and isn't supported

s/isn't/aren't/


+   in QEMU.
+
+  Description  DiskDescriptor.xml stores information about disk parameters,
+ file  snapshots, storages.
+
+ Top   The overlay between actual state and some previous snapshot.
+   SnapshotIt is not a snapshot in classical meaning.

To make this clearer the last line could be:

   It is not a snapshot in the classical sense because it serves as the
   active image that the guest writes to.


+
+Sector a 512-byte data chunk.
+
+== Description file ==
+All information is placed in single XML section Parallels_disk_image.
+The section has only one attribute "Version", that must be 1.0.
+General structure of DiskDescriptor.xml:
+
+
+
+...
+
+
+...
+
+
+...
+
+
+
+== Disk_Parameters section ==
+The Disk_Parameters section describes the physical layout of the virtual disk
+and some general settings.
+
+The Disk_Parameters section MUST contain the following subsections:
+* Disk_size - number

Re: [Qemu-block] [PATCH 2/5] configure: add dependency

[klim]

On 12/22/2017 03:38 PM, Roman Kagan wrote:

On Mon, Dec 18, 2017 at 02:09:08PM +0300, Denis V. Lunev wrote:

From: Klim Kireev <klim.kir...@virtuozzo.com>

This dependency is required for adequate Parallels images support.
Typically the disk consists of several images which are glued by
XML disk descriptor. Also XML hides inside several important parameters
which are not available in the image header.

The patch also adds clause to checkpatch.pl to understand libxml2 types.

Can't you get by with glib's GMarkup, to avoid extra dependencies?

https://developer.gnome.org/glib/stable/glib-Simple-XML-Subset-Parser.html

Roman.


Signed-off-by: Denis V. Lunev <d...@openvz.org>
Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhme...@virtuozzo.com>
CC: Stefan Hajnoczi <stefa...@redhat.com>
---
  configure | 27 +++
  block/Makefile.objs   |  2 ++
  scripts/checkpatch.pl |  1 +
  3 files changed, 30 insertions(+)

diff --git a/configure b/configure
index 0c6e757..e988fd0 100755
--- a/configure
+++ b/configure
@@ -422,6 +422,7 @@ tcmalloc="no"
  jemalloc="no"
  replication="yes"
  vxhs=""
+libxml2=""
  
  supported_cpu="no"

  supported_os="no"
@@ -1275,6 +1276,10 @@ for opt do
;;
--enable-numa) numa="yes"
;;
+  --disable-libxml2) libxml2="no"
+  ;;
+  --enable-libxml2) libxml2="yes"
+  ;;
--disable-tcmalloc) tcmalloc="no"
;;
--enable-tcmalloc) tcmalloc="yes"
@@ -1548,6 +1553,7 @@ disabled with --disable-FEATURE, default is enabled if 
available:
tpm TPM support
libssh2 ssh block device support
numalibnuma support
+  libxml2 for Parallels image format
tcmalloctcmalloc support
jemallocjemalloc support
replication replication support
@@ -1592,6 +1598,20 @@ if test "$ARCH" = "unknown"; then
  fi
  fi
  
+# check for libxml2

+if test "$libxml2" != "no" ; then
+if $pkg_config --exists libxml-2.0; then
+libxml2="yes"
+libxml2_cflags=$($pkg_config --cflags libxml-2.0)
+libxml2_libs=$($pkg_config --libs libxml-2.0)
+else
+if test "$libxml2" = "yes"; then
+feature_not_found "libxml2" "Install libxml2 devel"
+fi
+libxml2="no"
+fi
+fi
+
  # Consult white-list to determine whether to enable werror
  # by default.  Only enable by default for git builds
  if test -z "$werror" ; then
@@ -5549,6 +5569,7 @@ echo "lzo support   $lzo"
  echo "snappy support$snappy"
  echo "bzip2 support $bzip2"
  echo "NUMA host support $numa"
+echo "libxml2   $libxml2"
  echo "tcmalloc support  $tcmalloc"
  echo "jemalloc support  $jemalloc"
  echo "avx2 optimization $avx2_opt"
@@ -6208,6 +6229,12 @@ if test "$have_rtnetlink" = "yes" ; then
echo "CONFIG_RTNETLINK=y" >> $config_host_mak
  fi
  
+if test "$libxml2" = "yes" ; then

+  echo "CONFIG_LIBXML2=y" >> $config_host_mak
+  echo "LIBXML2_CFLAGS=$libxml2_cflags" >> $config_host_mak
+  echo "LIBXML2_LIBS=$libxml2_libs" >> $config_host_mak
+fi
+
  if test "$replication" = "yes" ; then
echo "CONFIG_REPLICATION=y" >> $config_host_mak
  fi
diff --git a/block/Makefile.objs b/block/Makefile.objs
index 6eaf78a..a73387f 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -47,3 +47,5 @@ block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
  dmg-bz2.o-libs := $(BZIP2_LIBS)
  qcow.o-libs:= -lz
  linux-aio.o-libs   := -laio
+parallels.o-cflags := $(LIBXML2_CFLAGS)
+parallels.o-libs   := $(LIBXML2_LIBS)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 34df753..e76cc85 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -265,6 +265,7 @@ our @typeList = (
qr{${Ident}_handler_fn},
qr{target_(?:u)?long},
qr{hwaddr},
+   qr{xml${Ident}},
  );
  
  # This can be modified by sub possible.  Since it can be empty, be careful

--
2.7.4


It is inconvenient, because GMarkup sees XML files as series of event, 
while for our purposes the tree model is much more preferable.


Also libvirt depends on libxml2, so it is installed in most cases.

[Qemu-block] [PATCH v3] qemu-img: add the simplest format recognition

[Klim Kireev]

Now, if you type something like

qemu-img create disk.qcow2 1G
or
qemu-img dd if=/dev/sda of=disk.qcow2

it creates a raw image and if you need you should
manually specify an image format with -f qcow2. It would
be more convenient if it could be assumed from an extension.

This patch adds a simple heuristic to recognize the image format
for qcow, qcow2, vmdk, vhdx, vdi

It warns users about guessed format and informs them about '-f' option.

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
---
 qemu-img.c | 20 ++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index 02a6e27beb..4ec04f5c86 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -421,11 +421,21 @@ static int64_t cvtnum(const char *s)
 return value;
 }
 
+static const char *get_format(const char *filename)
+{
+const char *fmt = strrchr(filename, '.');
+if (fmt == NULL || bdrv_find_format(++fmt) == NULL) {
+fmt = "raw";
+}
+warn_report("No format specified with -f, assuming %s.", fmt);
+return fmt;
+}
+
 static int img_create(int argc, char **argv)
 {
 int c;
 uint64_t img_size = -1;
-const char *fmt = "raw";
+const char *fmt = NULL;
 const char *base_fmt = NULL;
 const char *filename;
 const char *base_filename = NULL;
@@ -496,6 +506,9 @@ static int img_create(int argc, char **argv)
 
 /* Get the filename */
 filename = (optind < argc) ? argv[optind] : NULL;
+if (fmt == NULL) {
+fmt = get_format(filename);
+}
 if (options && has_help_option(options)) {
 g_free(options);
 return print_block_option_help(filename, fmt);
@@ -4181,7 +4194,7 @@ static int img_dd(int argc, char **argv)
 Error *local_err = NULL;
 bool image_opts = false;
 int c, i;
-const char *out_fmt = "raw";
+const char *out_fmt = NULL;
 const char *fmt = NULL;
 int64_t size = 0;
 int64_t block_count = 0, out_pos, in_pos;
@@ -4308,6 +4321,9 @@ static int img_dd(int argc, char **argv)
 goto out;
 }
 
+if (out_fmt == NULL) {
+out_fmt = get_format(out.filename);
+}
 drv = bdrv_find_format(out_fmt);
 if (!drv) {
 error_report("Unknown file format");
-- 
2.13.6

[Qemu-block] [PATCH v2] qemu-img: add the simplest format recognition

[Klim Kireev]

Now, if you type something like

qemu-img create disk.qcow2 1G
or
qemu-img dd if=/dev/sda of=disk.qcow2

it creates a raw image and if you need you should
manually specify an image format with -f qcow2. It would
be more convenient if it could be detected from an extension.

This patch adds a simple heuristic to recognize the image format
for qcow, qcow2, vmdk, vhdx, vdi

It warns users about guessed format and informs them about '-f' option.

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
---
 qemu-img.c | 21 +++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index 02a6e27beb..ac1adf1582 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -421,11 +421,22 @@ static int64_t cvtnum(const char *s)
 return value;
 }
 
+static const char *get_format(const char *filename)
+{
+const char *fmt = strrchr(filename, '.');
+if (fmt == NULL || bdrv_find_format(++fmt) == NULL) {
+fmt = "raw";
+}
+printf("!!! %s format was detected.\n"
+   "!!! If you meant another format, specify it with -f.\n", fmt);
+return fmt;
+}
+
 static int img_create(int argc, char **argv)
 {
 int c;
 uint64_t img_size = -1;
-const char *fmt = "raw";
+const char *fmt = NULL;
 const char *base_fmt = NULL;
 const char *filename;
 const char *base_filename = NULL;
@@ -496,6 +507,9 @@ static int img_create(int argc, char **argv)
 
 /* Get the filename */
 filename = (optind < argc) ? argv[optind] : NULL;
+if (fmt == NULL) {
+fmt = get_format(filename);
+}
 if (options && has_help_option(options)) {
 g_free(options);
 return print_block_option_help(filename, fmt);
@@ -4181,7 +4195,7 @@ static int img_dd(int argc, char **argv)
 Error *local_err = NULL;
 bool image_opts = false;
 int c, i;
-const char *out_fmt = "raw";
+const char *out_fmt = NULL;
 const char *fmt = NULL;
 int64_t size = 0;
 int64_t block_count = 0, out_pos, in_pos;
@@ -4308,6 +4322,9 @@ static int img_dd(int argc, char **argv)
 goto out;
 }
 
+if (out_fmt == NULL) {
+out_fmt = get_format(out.filename);
+}
 drv = bdrv_find_format(out_fmt);
 if (!drv) {
 error_report("Unknown file format");
-- 
2.13.6

[Qemu-block] [PATCH] qemu-img: add the simplest format recognition

[Klim Kireev]

Now, if you type something like

qemu-img create disk.qcow2 1G
or
qemu-img dd if=/dev/sda of=disk.qcow2

it creates a raw image and if you need you should
manually specify an image format with -f qcow2. It would
be more convenient if it could be detected from an extension.

This patch adds a simple heuristic to recognize the image format
for qcow, qcow2, vmdk, vhdx, vdi

Signed-off-by: Klim Kireev <klim.kir...@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
---
 qemu-img.c | 24 ++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index 02a6e27beb..0a659d2257 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -421,11 +421,25 @@ static int64_t cvtnum(const char *s)
 return value;
 }
 
+static const char *get_format(const char *filename)
+{
+const char *fmt = strrchr(filename, '.');
+if (fmt == NULL) {
+return "raw";
+}
+fmt++;
+if (bdrv_find_format(fmt) != NULL) {
+return fmt;
+} else {
+return "raw";
+}
+}
+
 static int img_create(int argc, char **argv)
 {
 int c;
 uint64_t img_size = -1;
-const char *fmt = "raw";
+const char *fmt = NULL;
 const char *base_fmt = NULL;
 const char *filename;
 const char *base_filename = NULL;
@@ -496,6 +510,9 @@ static int img_create(int argc, char **argv)
 
 /* Get the filename */
 filename = (optind < argc) ? argv[optind] : NULL;
+if (fmt == NULL) {
+fmt = get_format(filename);
+}
 if (options && has_help_option(options)) {
 g_free(options);
 return print_block_option_help(filename, fmt);
@@ -4181,7 +4198,7 @@ static int img_dd(int argc, char **argv)
 Error *local_err = NULL;
 bool image_opts = false;
 int c, i;
-const char *out_fmt = "raw";
+const char *out_fmt = NULL;
 const char *fmt = NULL;
 int64_t size = 0;
 int64_t block_count = 0, out_pos, in_pos;
@@ -4308,6 +4325,9 @@ static int img_dd(int argc, char **argv)
 goto out;
 }
 
+if (out_fmt == NULL) {
+out_fmt = get_format(out.filename);
+}
 drv = bdrv_find_format(out_fmt);
 if (!drv) {
 error_report("Unknown file format");
-- 
2.13.6