Add an Error ** parameter to bdrv_create and its associated functions to
allow more specific error messages.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add an Error ** parameter to bdrv_open, bdrv_file_open and associated
functions to allow more specific error messages.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add an Error ** parameter to BlockDriver.bdrv_open and
BlockDriver.bdrv_file_open to allow more specific error messages.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Snapshot creation actually already distinguish id and name since it take
a structured parameter *sn, but delete can't. Later an accurate delete
is needed in qmp_transaction abort and blockdev-snapshot-delete-sync,
so change its prototype. Also *errp is added to tip error, but return
value is kepted to let caller check what kind of error happens. Existing
caller for it are savevm, delvm and qemu-img, they are not impacted by
introducing a new function bdrv_snapshot_delete_by_id_or_name(), which
check the return value and do the operation again.
Before this patch:
For qcow2, it search id first then name to find the one to delete.
For rbd, it search name.
For sheepdog, it does nothing.
After this patch:
For qcow2, logic is the same by call it twice in caller.
For rbd, it always fails in delete with id, but still search for name
in second try, no change to user.
Some code for *errp is based on Pavel's patch.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
To make it clear about id and name in searching, add this API
to distinguish them. Caller can choose to search by id or name,
*errp will be set only for exception.
Some code are modified based on Pavel's patch.
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Implement bdrv_amend_options for compat, size, backing_file, backing_fmt
and lazy_refcounts.
Downgrading images from compat=1.1 to compat=0.10 is achieved through
handling all incompatible flags accordingly, clearing all compatible and
autoclear flags and expanding all zero clusters.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Save the image refcount order in BDRVQcowState. This will be relevant
for future code supporting different refcount orders than four and also
for code that needs to verify a certain refcount order for an opened
image.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add functionality for expanding zero clusters. This is necessary for
downgrading the image version to one without zero cluster support.
For non-backed images, this function may also just discard zero clusters
instead of truly expanding them.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add a function for emptying a cache, i.e., flushing it and marking all
elements invalid.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is a valid case that the read data's size is smaller than the
requested size since there could be files that are smaller than
the minimum block size (For ex. when a VMDK disk descriptor file)
Signed-off-by: Tal Kain <tal.kain@ravellosystems.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
During savevm, the VM state is written to the active L1 of the image and
then a snapshot is taken. After that, the VM state isn't needed any more
in the active L1 and should be discarded. This is implemented by this
patch.
The impact of not discarding the VM state is that a snapshot can never
become smaller than any previous snapshot (because it would be padded
with old VM state), and more importantly that future savevm operations
cause unnecessary COWs (with associated flushes), which makes subsequent
snapshots much slower.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The function will be used internally instead of only being called for
guest discard requests.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
These are created for example with XFS_IOC_ZERO_RANGE.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
For now, bdrv_get_block_status is just another name for bdrv_is_allocated.
The next patches will add more flags.
This also touches all block drivers with a mostly mechanical rename. The
sole exception is cow; because it calls cow_co_is_allocated from the read
code, we keep that function and make cow_co_get_block_status a wrapper.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Some bdrv_is_allocated callers do not expect errors, but the fallback
in qcow2.c might make other callers trip on assertion failures or
infinite loops.
Fix the callers to always look for errors.
Cc: qemu-stable@nongnu.org
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Now that bdrv_is_allocated detects coroutine context, the two can
use the same code.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_is_allocated can detect coroutine context and go through a fast
path, similar to other block layer functions.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
As we change bdrv_is_allocated to gather more information from bs and
bs->file, it will become a bit slower. It is still appropriate for online
jobs, but not for reads/writes. Call the internal function instead.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Only sync once per write, rather than once per sector.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Do not do two reads for each sector; load each sector of the bitmap
and use bitmap operations to process it.
Writes are still dog slow!
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no
longer public and should be called by bdrv_unref() if refcnt is
decreased to 0.
This is an identical change because effectively, there's no multiple
reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets
bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
BlockDriverState structure needs bdrv_new() to initialize refcnt, don't
allocate a local structure variable and memset to 0, becasue with coming
refcnt implementation, bdrv_unref will crash if bs->refcnt not
initialized to 1.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
we need bdrv_new() to properly initialize BDS, don't allocate memory
manually.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
QEMU failed to open host devices like \\.\PhysicalDrive0 (first hard disk)
since some time (commit 8a79380b8ef1b02d2abd705dd026a18863b09020?).
Those devices use hdev_open which did not use the latest API for options.
This resulted in a fatal runtime error:
Block protocol 'host_device' doesn't support the option 'filename'
Duplicate code from raw_open to fix this.
Cc: qemu-stable@nongnu.org
Reported-by: David Brenner <david.brenner3@gmail.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This feature can be used in case where users are avoiding the iops limit by
doing jumbo I/Os hammering the storage backend.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The max parameter of the leaky bucket throttling algorithm can be used to
allow the guest to do bursts.
The max value is a pool of I/O that the guest can use without being throttled
at all. Throttling is triggered once this pool is empty.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If no corruptions remain after an image repair (and no errors have been
encountered), clear the corrupt flag in qcow2_check.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If the refcount of a refcount block is greater than one, we can at least
try to repair that problem by duplicating the affected block.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Drop error code path which cannot be taken since qemu_bh_new() does not
return NULL.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Most typos were found using a modified version of codespell:
accross -> across
issueing -> issuing
TICNT_THRESHHOLD -> TICNT_THRESHOLD
bandwith -> bandwidth
VCARD_7816_PROPIETARY -> VCARD_7816_PROPRIETARY
occured -> occurred
gaurantee -> guarantee
sofware -> software
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Since the OFLAG_COPIED checks are now executed after the refcounts have
been repaired (if repairing), it is safe to assume that they are correct
but the OFLAG_COPIED flag may be not. Therefore, if its value differs
from what it should be (considering the according refcount), that
discrepancy can be repaired by correctly setting (or clearing that flag.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Move the OFLAG_COPIED checks out of check_refcounts_l1 and
check_refcounts_l2 and after the actual refcount checks/fixes (since the
refcounts might actually change there).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The pre-write overlap check function is now called before most of the
qcow2 writes (aborting it on collision or other error).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Two new functions are added; the first one checks a given range in the
image file for overlaps with metadata (main header, L1 tables, L2
tables, refcount table and blocks).
The second one should be used immediately before writing to the image
file as it calls the first function and, upon collision, marks the
image as corrupt and makes the BDS unusable, thereby preventing
further access.
Both functions take a bitmask argument specifying the structures which
should be checked for overlaps, making it possible to also check
metadata writes against colliding with other structures.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds an incompatible bit indicating corruption to qcow2. Any image
with this bit set may not be written to unless for repairing (and
subsequently clearing the bit if the repair has been successful).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Account for all cluster types in qcow2_update_snapshot_refcounts;
this prevents this function from updating the refcount of unallocated
zero clusters which effectively led to wrong adjustments of the refcount
of cluster 0 (the main qcow2 header). This in turn resulted in images
with (unallocated) zero clusters having a cluster 0 refcount greater
than one after creating a snapshot.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently if gluster AIO callback thread fails to notify the QEMU thread about
AIO completion, we try graceful recovery by marking the disk drive as
inaccessible. This error recovery code is race-prone as found by Asias and
Stefan. However as found out by Paolo, this kind of error is impossible and
hence simplify the code that handles this error recovery.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
"Incoming" function prototypes and "outgoing" function calls must match
reality. Implemented using the "struct BlockDriver" definition in
"include/block/block_int.h", and gcc errors & warnings.
v1->v2:
On 08/20/13 09:51, Kevin Wolf wrote:
> Am 18.08.2013 um 16:29 hat Paolo Bonzini geschrieben:
>> Il 16/08/2013 16:15, Laszlo Ersek ha scritto:
>>> +static int raw_reopen_prepare(BDRVReopenState *reopen_state,
>>> + BlockReopenQueue *queue, Error **errp)
>>> {
>>> - return bdrv_reopen_prepare(bs->file);
>>> + BDRVReopenState tmp = *reopen_state;
>>> +
>>> + tmp.bs = tmp.bs->file;
>>> + return bdrv_reopen_prepare(&tmp, queue, errp);
>>> }
>>
>> This should just return zero, my fault.
>
> Which is because bdrv_reopen_queue() already queues bs->file for reopen.
> The simple return 0; implementation is shared by all other format drivers
> that support reopening images.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On 08/05/13 15:03, Paolo Bonzini wrote:
>
> [...]
>
> 5) Formats are registered with bdrv_register (takes a BlockDriver*). You
> also need to pass the caller of bdrv_register to block_init.
Fill in the BlockDriver structure with the raw_*() functions that have
been added to "block/raw_bsd.c", in the order the fields are defined in
"include/block/block_int.h".
I needed more explanation / naming examples for registering the driver
than what Paolo gave me, so I copied / adapted from "block/qcow2.c". The
parts I took as basis for modification are blamed on
commit 5efa9d5a8b
Author: Anthony Liguori <aliguori@us.ibm.com>
Date: Sat May 9 17:03:42 2009 -0500
Convert block infrastructure to use new module init functionality
commit 20d97356c9
Author: Blue Swirl <blauwirbel@gmail.com>
Date: Fri Apr 23 20:19:47 2010 +0000
Fix OpenBSD build
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On 08/05/13 15:03, Paolo Bonzini wrote:
>
> [...]
>
> 4) There is another member, .create_options, which is an array of
> QEMUOptionParameter structs, terminated by an all-zero item. The only
> option you need is for the virtual disk size. You will find something
> to copy from in other block drivers, for example block/qcow2.c.
Code taken and adapted from "block/qcow2.c", as suggested. The code being
copied/modified is blamed on
commit 20d97356c9
Author: Blue Swirl <blauwirbel@gmail.com>
Date: Fri Apr 23 20:19:47 2010 +0000
Fix OpenBSD build
and
commit 7c80ab3f21
Author: Jes Sorensen <Jes.Sorensen@redhat.com>
Date: Fri Dec 17 16:02:39 2010 +0100
block/qcow2.c: rename qcow_ functions to qcow2_
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On 08/05/13 15:03, Paolo Bonzini wrote:
>
> [...]
>
> 3) These members are special
>
> .format_name is the string "raw"
> .bdrv_open raw_open should set bs->sg to bs->file->sg and return 0
> .bdrv_close raw_close should do nothing
> .bdrv_probe raw_probe should just return 1.
v1->v2:
On 08/20/13 10:11, Kevin Wolf wrote:
> Am 16.08.2013 um 16:15 hat Laszlo Ersek geschrieben:
>> +static int raw_probe(void)
>> +{
>> + return 1;
>> +}
>
> Maybe add a comment here like "smallest possible positive score so that
> raw is used if and only if no other block driver works".
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On 08/05/13 15:03, Paolo Bonzini wrote:
>
> [...]
>
> 2) This is also a simple forwarder function:
>
> .bdrv_create
>
> but there is no BlockDriverState argument so the forwarded-to function
> does not have a bs->file argument either. The forwarded-to function is
> bdrv_create_file.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On 08/05/13 15:03, Paolo Bonzini wrote:
>
> [...]
>
> 1) BlockDriver is a struct in which these function members are
> interesting:
>
> .bdrv_reopen_prepare
> .bdrv_co_readv
> .bdrv_co_writev
> .bdrv_co_is_allocated
> .bdrv_co_write_zeroes
> .bdrv_co_discard
> .bdrv_getlength
> .bdrv_get_info
> .bdrv_truncate
> .bdrv_is_inserted
> .bdrv_media_changed
> .bdrv_eject
> .bdrv_lock_medium
> .bdrv_ioctl
> .bdrv_aio_ioctl
> .bdrv_has_zero_init
>
> They should be implemented as simple forwarders (see above). There are
> 16 functions listed here, you can easily see how this already accounts
> for 100+ SLOC roughly...
>
> The implementations of bdrv_co_readv and bdrv_co_writev should also call
> BLKDBG_EVENT on bs->file too, before forwarding to bs->file. The events
> to be generated are BLKDBG_READ_AIO and BLKDBG_WRITE_AIO.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On 08/05/13 15:03, Paolo Bonzini wrote:
>
>
> ----- Original Message -----
>> From: "Laszlo Ersek" <lersek@redhat.com>
>> To: "Paolo Bonzini" <pbonzini@redhat.com>
>> Sent: Monday, August 5, 2013 2:43:46 PM
>> Subject: Re: [PATCH 1/2] raw: add license header
>>
>> On 08/02/13 00:27, Paolo Bonzini wrote:
>>> On 08/01/2013 10:13 AM, Christoph Hellwig wrote:
>>>> On Wed, Jul 31, 2013 at 08:19:51AM +0200, Paolo Bonzini wrote:
>>>>> Most of the block layer is under the BSD license, thus it is
>>>>> reasonable to license block/raw.c the same way. CCed people should
>>>>> ACK by replying with a Signed-off-by line.
>>>>
>>>> The coded was intended to be GPLv2.
>>>
>>> Laszlo, would you be willing to do clean-room reverse engineering?
>>>
>>> (No rants, please. :))
>>
>> What's the scope exactly?
>
> It's quite small, it's a file full of forwarders like
>
> static void raw_foo(BlockDriverState *bs)
> {
> return bdrv_foo(bs->file);
> }
>
> It's 170 lines of code, all as boring as this. I only picked you
> because I'm quite certain you have never seen the file (and the answer
> confirmed it).
>
> Basically:
>
> 1) BlockDriver is a struct in which these function members are
> interesting:
>
> .bdrv_reopen_prepare
> .bdrv_co_readv
> .bdrv_co_writev
> .bdrv_co_is_allocated
> .bdrv_co_write_zeroes
> .bdrv_co_discard
> .bdrv_getlength
> .bdrv_get_info
> .bdrv_truncate
> .bdrv_is_inserted
> .bdrv_media_changed
> .bdrv_eject
> .bdrv_lock_medium
> .bdrv_ioctl
> .bdrv_aio_ioctl
> .bdrv_has_zero_init
>
> They should be implemented as simple forwarders (see above).
> There are 16 functions listed here, you can easily see how this
> already accounts for 100+ SLOC roughly...
>
> The implementations of bdrv_co_readv and bdrv_co_writev should also
> call BLKDBG_EVENT on bs->file too, before forwarding to bs->file. The
> events to be generated are BLKDBG_READ_AIO and BLKDBG_WRITE_AIO.
>
> 2) This is also a simple forwarder function:
>
> .bdrv_create
>
> but there is no BlockDriverState argument so the forwarded-to function
> does not have a bs->file argument either. The forwarded-to function
> is bdrv_create_file.
>
> 3) These members are special
>
> .format_name is the string "raw"
> .bdrv_open raw_open should set bs->sg to bs->file->sg and return 0
> .bdrv_close raw_close should do nothing
> .bdrv_probe raw_probe should just return 1.
>
> 4) There is another member, .create_options, which is an array of
> QEMUOptionParameter structs, terminated by an all-zero item. The only
> option you need is for the virtual disk size. You will find something
> to copy from in other block drivers, for example block/qcow2.c.
>
> 5) Formats are registered with bdrv_register (takes a BlockDriver*).
> You also need to pass the caller of bdrv_register to block_init.
>
> 6) I'm not sure how to organize the patch series, so I'll leave this to
> your creativity. I guess in this case move/copy detection of git should
> be disabled. I would definitely include this spec in the commit
> message as a proof of clean-room reverse engineering.
>
> 7) Remember a BSD header like the one in block.c.
>
> Paolo
This patch implements the email up to the paragraph ending with "100+ SLOC
roughly". The skeleton is generated from the list there, with a simple
shell loop using "sed" and the raw_foo() template.
The BSD license block is copied (and reflowed) from
"util/qemu-progress.c".
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
