.has_zero_init defaults to 1 for all formats and protocols.
this is a dangerous default since this means that all
new added drivers need to manually overwrite it to 0 if
they do not ensure that a device is zero initialized
after bdrv_create().
if a driver needs to explicitly set this value to
1 its easier to verify the correctness in the review process.
during review of the existing drivers it turned out
that ssh and gluster had a wrong default of 1.
both protocols support host_devices as backend
which are not by default zero initialized. this
wrong assumption will lead to possible corruption
if qemu-img convert is used to write to such a backend.
vpc and vmdk also defaulted to 1 altough they support
fixed respectively flat extends. this has to be addresses
in separate patches. both formats as well as the mentioned
ssh and gluster are turned to the default of 0 with this
patch for safety.
a similar problem with the wrong default existed for
iscsi most likely because the driver developer did
oversee the default value of 1.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Depending on the subformat, has_zero_init on VHD must behave like raw
and query the underlying storage (fixed) or like other sparse formats
that can always return 1 (dynamic, differencing).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When creating image with backing file, the driver tries to calculate the
relative path from created image file to backing file, but the path
computation is incorrect. e.g.:
$ qemu-img create -f vmdk -b vmdk-data-disk.vmdk vmdk-data-snapshot1
Formatting 'vmdk-data-snapshot1', fmt=vmdk size=10737418240
backing_file='vmdk-data-disk.vmdk' compat6=off zeroed_grain=off
$ qemu-img info vmdk-data-snapshot1
image: vmdk-data-snapshot1
file format: vmdk
virtual size: 10G (10737418240 bytes)
disk size: 12K
-> backing file: disk.vmdk
The common part in file names, "vmdk-data-", is incorrectly forgotten by
relative_path(). As the VMDK specification has no restriction on
parentNameHint to be relative path, we simply remove this by using the
backing_file option.
Cc: qemu-stable@nongnu.org
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
GlusterFS volumes can be backed by block devices, in which case
bdrv_create() doesn't make sure that the image is zeroed out. It is
currently not possibly to detect whether a given image is backed by a
file or a block device, and incorrectly assuming that it is zeroed
corrupts images during qemu-img convert, so let's err on the side of
caution and always return 0.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If the remote is a regular file, set it to true (ie. reads of
uninitialized areas in a newly created file will return zeroes).
If we can't prove that, return false (a safe default).
Tested by adding a debugging print statement [not part of this commit]
and creating a remote file and a remote block device:
$ ./qemu-img create ssh://localhost/tmp/new 100M
Formatting 'ssh://localhost/tmp/new', fmt=raw size=104857600
filename ssh://localhost/tmp/new: has_zero_init = 1
$ sudo lvcreate -L 1G -n tmp /dev/fedora
Logical volume "tmp" created
$ ./qemu-img create ssh://localhost/dev/fedora/tmp 1G
Formatting 'ssh://localhost/dev/fedora/tmp', fmt=raw size=1073741824
filename ssh://localhost/dev/fedora/tmp: has_zero_init = 0
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
backup_start() creates a block job that copies a point-in-time snapshot
of a block device to a target block device.
We call backup_do_cow() for each write during backup. That function
reads the original data from the block device before it gets
overwritten. The data is then written to the target device.
Currently backup cluster size is hardcoded to 65536 bytes.
[I made a number of changes to Dietmar's original patch and folded them
in to make code review easy. Here is the full list:
* Drop BackupDumpFunc interface in favor of a target block device
* Detect zero clusters with buffer_is_zero() and use bdrv_co_write_zeroes()
* Use 0 delay instead of 1us, like other block jobs
* Unify creation/start functions into backup_start()
* Simplify cleanup, free bitmap in backup_run() instead of cb
* function
* Use HBitmap to avoid duplicating bitmap code
* Use bdrv_getlength() instead of accessing ->total_sectors
* directly
* Delete the backup.h header file, it is no longer necessary
* Move ./backup.c to block/backup.c
* Remove #ifdefed out code
* Coding style and whitespace cleanups
* Use bdrv_add_before_write_notifier() instead of blockjob-specific hooks
* Keep our own in-flight CowRequest list instead of using block.c
tracked requests. This means a little code duplication but is much
simpler than trying to share the tracked requests list and use the
backup block size.
* Add on_source_error and on_target_error error handling.
* Use trace events instead of DPRINTF()
-- stefanha]
Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The raw-posix driver has code to provide a /dev/cdrom on OS X even
though it doesn't really exist. However, since commit c66a6157 the real
filename is dismissed after finding it, so opening /dev/cdrom fails.
Put the filename back into the options QDict to make this work again.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Refuse to open higher version for safety.
Although we try to be compatible with published VMDK spec, VMware has
newer version from ESXi 5.1 exported OVF/OVA, which we have no knowledge
what's changed in it. And it is very likely to have more new versions in
the future, so it's not safe to open them blindly.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This optimises the discard operation for freed clusters by batching
discard requests (both snapshot deletion and bdrv_discard end up
updating the refcounts cluster by cluster).
Note that we don't discard asynchronously, but keep s->lock held. This
is to avoid that a freed cluster is reallocated and written to while the
discard is still in flight.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Deleted snapshots are discarded in the image file by default, discard
requests take their default from the -drive discard=... option and other
places that free clusters must always be enabled explicitly.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds a refcount update reason to all callers of update_refcounts(),
so that a follow-up patch can use this information to decide whether
clusters that reach a refcount of 0 should be discarded in the image
file.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
# By Paolo Bonzini (3) and others
# Via Paolo Bonzini
* bonzini/scsi-next:
iscsi: reorganize iscsi_readcapacity_sync
iscsi: simplify freeing of tasks
vhost-scsi: fix k->set_guest_notifiers() NULL dereference
scsi-disk: scsi-block device for scsi pass-through should not be removable
scsi-generic: check the return value of bdrv_aio_ioctl in execute_command
scsi-generic: fix sign extension of READ CAPACITY(10) data
scsi: reset cdrom tray statuses on scsi_disk_reset
Message-id: 1371565016-2643-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Avoid the goto, and use the same retry logic for the 10- and 16-
byte versions.
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Always free them in the iscsi_aio_*_acb functions and remove the
checks in their callers. Remove ifs when the task struct was
previously dereferenced (spotted by Coverity).
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Otherwise they would get passed to getaddrinfo and fail with:
address resolution failed for [::1]🔢 Name or service not known
(Broken by commit v1.4.0-736-gf17c90b)
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
# By Luiz Capitulino
# Via Luiz Capitulino
* luiz/queue/qmp:
qerror: drop QERR_OPEN_FILE_FAILED macro
block: bdrv_reopen_prepare(): don't use QERR_OPEN_FILE_FAILED
savevm: qmp_xen_save_devices_state(): use error_setg_file_open()
dump: qmp_dump_guest_memory(): use error_setg_file_open()
cpus: use error_setg_file_open()
blockdev: use error_setg_file_open()
block: mirror_complete(): use error_setg_file_open()
rng-random: use error_setg_file_open()
error: add error_setg_file_open() helper
Message-id: 1371484631-29510-1-git-send-email-lcapitulino@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
the hard-coded 2k buffer on the stack won't allow reading big descriptor
files which can be generated when storing big images. For example 500G
vmdk splitted to 2G chunks.
Signed-off-by: Evgeny Budilovsky <evgeny.budilovsky@ravellosystems.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(Found by Kamil Dudka)
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Cc: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Remember to byteswap VMDK4Header.desc_offset on big-endian machines.
Cc: qemu-stable@nongnu.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Just call sd_create_branch() in the snapshot_goto to rollback the image is good
enough. With this patch, 'loadvm' process for sheepdog is modified:
Suppose we have a snapshot chain A --> B --> C, we do 'loadvm A' so as to get
a new chain,
A --> B
|
V
C1
in the old code:
1 reload inode of A (in snapshot_goto)
2 read vmstate via A's vdi_id (loadvm_state)
3 delete C and create C1, reload inode of C1 (sd_create_branch on write)
with this patch applied:
1 reload inode of A, delete C and create C1 (in snapshot_goto)
2 read vmstate via C1's parent, that is A's vdi_id (loadvm_state)
This will fix the possible bug that QEMU exit between 2 and 3 in the old code
Cc: qemu-devel@nongnu.org
Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This is an old and obvious bug. We should pass snapshot_id to the
tag. Or simple command like 'qemu-img snapshot -a tag sheepdog:image' will fail
Cc: qemu-devel@nongnu.org
Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Now image info will be retrieved as an embbed json object inside
BlockDeviceInfo, backing chain info and all related internal snapshot
info can be got in the enhanced recursive structure of ImageInfo. New
recursive member *backing-image is added to reflect the backing chain
status.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch adds function bdrv_query_image_info(), which will
retrieve image info in qmp object format. The implementation is
based on the code moved from qemu-img.c, but uses block layer
function to get snapshot info.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch adds function bdrv_query_snapshot_info_list(), which will
retrieve snapshot info of an image in qmp object format. The implementation
is based on the code moved from qemu-img.c with modification to fit more
for qmp based block layer API.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_snapshot_dump() and bdrv_image_info_dump() do not dump to a buffer now,
some internal buffers are still used for format control, which have no
chance to be truncated. As a result, these two functions have no more issue
of truncation, and they can be used by both qemu and qemu-img with correct
parameter specified.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch is a pure code move patch, except following modification:
1 get_human_readable_size() is changed to static function.
2 dump_human_image_info() is renamed to bdrv_image_info_dump().
3 in qmp_query_block() and qmp_query_blockstats, use bdrv_next(bs)
instead of direct traverse of global array 'bdrv_states'.
4 collect_snapshots() and collect_image_info() are renamed, unused parameter
*fmt in collect_image_info() is removed.
5 code style fix.
To avoid conflict and tip better, macro in header file is BLOCK_QAPI_H
instead of QAPI_H. Now block.h and snapshot.h are at the same level in
include path, block_int.h and qapi.h will both include them.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
All snapshot related code, except bdrv_snapshot_dump() and
bdrv_is_snapshot(), is moved to block/snapshot.c. bdrv_snapshot_dump()
will be moved to another file later. bdrv_is_snapshot() is not related
with internal snapshot. It also fixes small code style errors reported
by check script.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch is used to remove twice include of "qemu-common.h" in
block/win32-aio.c
Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This catches the situation that is described in the bug report at
https://bugs.launchpad.net/qemu/+bug/865518 and goes like this:
$ qemu-img create -f qcow2 huge.qcow2 $((1024*1024))T
Formatting 'huge.qcow2', fmt=qcow2 size=1152921504606846976 encryption=off cluster_size=65536 lazy_refcounts=off
$ qemu-io /tmp/huge.qcow2 -c "write $((1024*1024*1024*1024*1024*1024 - 1024)) 512"
Segmentation fault
With this patch applied the segfault will be avoided, however the case
will still fail, though gracefully:
$ qemu-img create -f qcow2 /tmp/huge.qcow2 $((1024*1024))T
Formatting 'huge.qcow2', fmt=qcow2 size=1152921504606846976 encryption=off cluster_size=65536 lazy_refcounts=off
qemu-img: The image size is too large for file format 'qcow2'
Note that even long before these overflow checks kick in, you get
insanely high memory usage (up to INT_MAX * sizeof(uint64_t) = 16 GB for
the L1 table), so with somewhat smaller image sizes you'll probably see
qemu aborting for a failed g_malloc().
If you need huge image sizes, you should increase the cluster size to
the maximum of 2 MB in order to get higher limits.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <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 <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Previously VmdkMetaData.offset is stored little endian while other
fields are cpu endian. This changes offset to cpu endian and convert
before writing to image.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add image create option "zeroed-grain" to enable zeroed-grain GTE
feature of vmdk sparse extents. When this option is on, header version
of newly created extent will be 2 and VMDK4_FLAG_ZERO_GRAIN flag bit
will be set.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Introduced support for zeroed-grain GTE, as specified in Virtual Disk
Format 5.0[1].
Recent VMware hosted platform products support a new “zeroed‐grain”
grain table entry (GTE). The zeroed‐grain GTE returns all zeros on
read. In other words, the zeroed‐grain GTE indicates that a grain
in the child disk is zero‐filled but does not actually occupy space
in storage. A sparse extent with zeroed‐grain GTE has the following
in its header:
* SparseExtentHeader.version = 2
* SparseExtentHeader.flags has bit 2 set
Other than the new flag and the possibly zeroed‐grain GTE, version 2
sparse extents are identical to version 1. Also, a zeroed‐grain GTE
has value 0x1 in the GT table.
[1] Virtual Disk Format 5.0, http://www.vmware.com/support/developer/vddk/vmdk_50_technote.pdf?src=vmdk
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Internal routines in vmdk.c previously return -1 on error and 0 on
success. More return values are useful for future changes such as
zeroed-grain GTE. Change all the magic `return 0` and `return -1` to
macro names:
* VMDK_OK 0
* VMDK_ERROR (-1)
* VMDK_UNALLOC (-2)
* VMDK_ZEROED (-3)
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds in read-only support to the VHDX image format. This supports
reads for fixed-size, and dynamic sized VHDX images.
Differencing files are still unsupported.
The image must be opened without BDRV_O_RDWR set, because we do not
yet update the headers. I.e., pass 'readonly=on' in the drive image
options from the QEMU commandline.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is the initial block driver framework for VHDX image support
(i.e. Hyper-V image file formats), that supports opening VHDX files, and
parsing the headers.
This commit does not yet enable:
- reading
- writing
- updating the header
- differencing files (images with parents)
- log replay / dirty logs (only clean images)
This is based on Microsoft's VHDX specification:
"VHDX Format Specification v0.95", published 4/12/2012
https://www.microsoft.com/en-us/download/details.aspx?id=29681
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is based on Microsoft's VHDX specification:
"VHDX Format Specification v0.95", published 4/12/2012
https://www.microsoft.com/en-us/download/details.aspx?id=29681
These structures define the various header, metadata, and other
block structures defined in the VHDX specification.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently the 'loadvm' opertaion works as following:
1. switch to the snapshot
2. mark current working VDI as a snapshot
3. rely on sd_create_branch to create a new working VDI based on the snapshot
This works not the same as other format as QCOW2. For e.g,
qemu > savevm # get a live snapshot snap1
qemu > savevm # snap2
qemu > loadvm 1 # This will steally create snap3 of the working VDI
Which will result in following snapshot chain:
base <-- snap1 <-- snap2 <-- snap3
^
|
working VDI
snap3 was unnecessarily created and might be annoying users.
This patch discard the unnecessary 'snap3' creation. and implement
rollback(loadvm) operation to the specified snapshot by
1. switch to the snapshot
2. delete working VDI
3. rely on sd_create_branch to create a new working VDI based on the snapshot
The snapshot chain for above example will be:
base <-- snap1 <-- snap2
^
|
working VDI
Cc: qemu-devel@nongnu.org
Cc: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <tailai.ly@taobao.com>
Reviewed-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When a snapshot is taken from out side of qemu (e.g. qemu-img
snapshot), write requests to the current vdi return SD_RES_READONLY.
In this case, the sheepdog block driver needs to update the current
inode to the latest one and resend the write requests.
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds a helper function to update the current inode state with the
specified vdi object.
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Sheepdog returns SD_RES_READONLY when qemu sends write requests to the
snapshot vdi. This adds the result code and makes sd_strerror() print
its error reason.
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This makes 'filename' and 'tag' constant variables, and renames
'for_snapshot' to 'lock' to clear how it works.
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Commit a9ccedc3 frees the QemuOpts for the driver-specific options
immediately, even though it still needs the filename string that is
contained there. This doesn't work. Move the deletion of the QemuOpts to
the end of the function where its content isn't needed any more.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
