Commit Graph

56 Commits

Author SHA1 Message Date
Kevin Wolf 03e35d820d stream: Use BlockBackend for I/O
This changes the streaming block job to use the job's BlockBackend for
performing the COR reads. job->bs isn't used by the streaming code any
more afterwards.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25 19:04:21 +02:00
Kevin Wolf 66a0fae438 blockjob: Don't touch BDS iostatus
Block jobs don't actually make use of the iostatus for their BDSes, but
they manage a separate block job iostatus. Still, they require that it
is enabled for the source BDS and they enable it automatically for the
target and set the error handling mode - which ends up never being used
by the job.

This patch removes all of the BDS iostatus handling from the block job,
which removes another few bs->blk accesses.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:45:31 +02:00
Kevin Wolf 81e254dc83 blockjob: Don't set iostatus of target
When block job errors were introduced, we assigned the iostatus of the
target BDS "just in case". The field has never been accessible for the
user because the target isn't listed in query-block.

Before we can allow the user to have a second BlockBackend on the
target, we need to clean this up. If anything, we would want to set the
iostatus for the internal BB of the job (which we can always do later),
but certainly not for a separate BB which the job doesn't even use.

As a nice side effect, this gets us rid of another bs->blk use.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:45:31 +02:00
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Merge remote-tracking branch 'remotes/cody/tags/block-pull-request' into staging

# gpg: Signature made Tue 29 Mar 2016 01:48:09 BST using RSA key ID C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"

* remotes/cody/tags/block-pull-request:
  qemu-iotests: add no-op streaming test
  qemu-iotests: fix test_stream_partial()
  block: never cancel a streaming job without running stream_complete()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-03-29 19:54:49 +01:00
Alberto Garcia 6578629e08 block: never cancel a streaming job without running stream_complete()
We need to call stream_complete() in order to do all the necessary
clean-ups, even if there's an early failure. At the moment it's only
useful to make sure that s->backing_file_str is not leaked, but it
will become more important if we introduce support for streaming to
any intermediate node.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 2abedf2debc65c250560237f31a8e6756883c8fc.1458566441.git.berto@igalia.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-03-28 13:56:44 -04:00
Markus Armbruster da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell 80c71a241a block: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20 13:36:23 +01:00
Max Reitz 373340b26c block: Move I/O status and error actions into BB
These options are only relevant for the user of a whole BDS tree (like a
guest device or a block job) and should thus be moved into the
BlockBackend.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-10-23 18:18:23 +02:00
Kevin Wolf 5db15a5769 block: Manage backing file references in bdrv_set_backing_hd()
This simplifies the code somewhat, especially when dropping whole
backing file subchains.

The exception is the mirroring code that does adventurous things with
bdrv_swap() and in order to keep it working, I had to duplicate most of
bdrv_set_backing_hd() locally. We'll get rid again of this ugliness
shortly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Kevin Wolf 760e006384 block: Convert bs->backing_hd to BdrvChild
This is the final step in converting all of the BlockDriverState
pointers that block drivers use to BdrvChild.

After this patch, bs->children contains the full list of child nodes
that are referenced by a given BDS, and these children are only
referenced through BdrvChild, so that updating the pointer in there is
enough for changing edges in the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Markus Armbruster cc7a8ea740 Include qapi/qmp/qerror.h exactly where needed
In particular, don't include it into headers.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:41 +02:00
Markus Armbruster c6bd8c706a qerror: Clean up QERR_ macros to expand into a single string
These macros expand into error class enumeration constant, comma,
string.  Unclean.  Has been that way since commit 13f59ae.

The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.

Clean up as follows:

* Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and
  delete it from the QERR_ macro.  No change after preprocessing.

* Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into
  error_setg(...).  Again, no change after preprocessing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Stefan Hajnoczi f3e69beb94 block: let stream blockjob run in BDS AioContext
The stream block job must run in the BlockDriverState AioContext so that
it works with dataplane.

The basics of acquiring the AioContext are easy in blockdev.c.

The tricky part is the completion code which drops part of the backing
file chain.  This must be done in the main loop where bdrv_unref() and
bdrv_close() are safe to call.  Use block_job_defer_to_main_loop() to
achieve that.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-9-git-send-email-stefanha@redhat.com
2014-11-03 11:41:49 +00:00
Markus Armbruster 097310b53e block: Rename BlockDriverCompletionFunc to BlockCompletionFunc
I'll use it with block backends shortly, and the name is going to fit
badly there.  It's a block layer thing anyway, not just a block driver
thing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:27 +02:00
Kevin Wolf 3baca89139 block: Add Error argument to bdrv_refresh_limits()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-18 13:18:43 +01:00
Jeff Cody 13d8cc515d block: add backing-file option to block-stream
On some image chains, QEMU may not always be able to resolve the
filenames properly, when updating the backing file of an image
after a block job.

For instance, certain relative pathnames may fail, or drives may
have been specified originally by file descriptor (e.g. /dev/fd/???),
or a relative protocol pathname may have been used.

In these instances, QEMU may lack the information to be able to make
the correct choice, but the user or management layer most likely does
have that knowledge.

With this extension to the block-stream api, the user is able to change
the backing file of the active layer as part of the block-stream
operation.

This allows the change to be 'safe', in the sense that if the attempt
to write the active image metadata fails, then the block-stream
operation returns failure, without disrupting the guest.

If a backing file string is not specified in the command, the backing
file string to use is determined in the same manner as it was
previously.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-01 10:47:01 +02:00
Wenchao Xia a589569f2f qapi: adjust existing defines
In order to let event defines use existing types later, instead of
redefine new ones, some old type defines for spice and vnc are changed,
and BlockErrorAction is moved from block.h to qapi schema. Note that
BlockErrorAction is not merged with BlockdevOnError.

At this point, VncInfo is not made a child of VncBasicInfo, because
VncBasicInfo has mandatory fields where VncInfo makes them optional.

Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-23 11:01:25 -04:00
Fam Zheng 920beae103 block: Use bdrv_set_backing_hd everywhere
We need to handle the coming backing_blocker properly, so don't open
code the assignment, instead, call bdrv_set_backing_hd to change
backing_hd.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-05-28 14:28:46 +02:00
Kevin Wolf 355ef4ac95 block: Update BlockLimits when they might have changed
When reopening with different flags, or when backing files disappear
from the chain, the limits may change. Make sure they get updated in
these cases.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit@irqsave.net>
2014-01-24 17:40:01 +01:00
Max Reitz f4a193e717 block/stream: Don't stream unbacked devices
If a block device is unbacked, a streaming blockjob should immediately
finish instead of beginning to try to stream, then noticing the backing
file does not contain even the first sector (since it does not exist)
and then finishing normally.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-11-28 11:39:31 +01:00
Fam Zheng 79e14bf778 qapi: make use of new BlockJobType
Switch the string to enum type BlockJobType in BlockJobDriver.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Fam Zheng 3fc4b10af0 blockjob: rename BlockJobType to BlockJobDriver
We will use BlockJobType as the enum type name of block jobs in QAPI,
rename current BlockJobType to BlockJobDriver, which will eventually
become a set of operations, similar to block drivers.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Stefan Weil c3e4f43a99 block: Fix compiler warning (-Werror=uninitialized)
The patch fixes a warning from gcc (Debian 4.6.3-14+rpi1) 4.6.3:

block/stream.c:141:22: error:
‘copy’ may be used uninitialized in this function [-Werror=uninitialized]

This is not a real bug - a better compiler would not complain.

Now 'copy' has always a defined value, so the check for ret >= 0
can be removed.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-25 16:21:28 +02:00
Paolo Bonzini d663640c04 block: expect errors from bdrv_co_is_allocated
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>
2013-09-06 15:25:09 +02:00
Paolo Bonzini 4f5786376e block: remove bdrv_is_allocated_above/bdrv_co_is_allocated_above distinction
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>
2013-09-06 15:25:09 +02:00
Paolo Bonzini bdad13b9de block: make bdrv_co_is_allocated static
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>
2013-09-06 15:25:08 +02:00
Fam Zheng 4f6fd3491c block: make bdrv_delete() static
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>
2013-09-06 15:25:08 +02:00
Alex Bligh 7483d1e547 aio / timers: convert block_job_sleep_ns and co_sleep_ns to new API
Convert block_job_sleep_ns and co_sleep_ns to use the new timer
API.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 19:14:24 +02:00
Stefan Hajnoczi 88266f5aa7 block: stop relying on io_flush() in bdrv_drain_all()
If a block driver has no file descriptors to monitor but there are still
active requests, it can return 1 from .io_flush().  This is used to spin
during synchronous I/O.

Stop relying on .io_flush() and instead check
QLIST_EMPTY(&bs->tracked_requests) to decide whether there are active
requests.

This is the first step in removing .io_flush() so that event loops no
longer need to have the concept of synchronous I/O.  Eventually we may
be able to kill synchronous I/O completely by running everything in a
coroutine, but that is future work.

Note this patch moves bs->throttled_reqs initialization to bdrv_new() so
that bdrv_requests_pending(bs) can safely access it.  In practice bs is
g_malloc0() so the memory is already zeroed but it's safer to initialize
the queue properly.

We also need to fix up block/stream.c:close_unused_images() to prevent
traversing a dangling pointer while it rearranges the backing file
chain.  This is necessary since the new bdrv_drain_all() traverses the
backing file chain.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:45:34 +02:00
Kevin Wolf f59fee8d50 block: Make BlockJobTypes const
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:27 +02:00
Paolo Bonzini 737e150e89 block: move include files to include/block/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:31:31 +01:00
Kevin Wolf c57b6656c3 aio: Get rid of qemu_aio_flush()
There are no remaining users, and new users should probably be
using bdrv_drain_all() in the first place.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-12-11 11:04:25 +01:00
Paolo Bonzini 65f4632243 block: rename block_job_complete to block_job_completed
The imperative will be used for the QMP command.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-10-24 10:26:19 +02:00
Paolo Bonzini 1d809098aa stream: add on-error argument
This patch adds support for error management to streaming.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-09-28 19:40:56 +02:00
Paolo Bonzini 2f0c9fe64c block: move job APIs to separate files
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-09-28 19:14:26 +02:00
Stefan Hajnoczi 571cd9dcc7 stream: complete early if end of backing file is reached
It is possible to create an image that is larger than its backing file.
Reading beyond the end of the backing file produces zeroes if no writes
have been made to those sectors in the image file.

This patch finishes streaming early when the end of the backing file is
reached.  Without this patch the block job hangs and continually tries
to stream the first sectors beyond the end of the backing file.

To reproduce the hung block job bug:

  $ qemu-img create -f qcow2 backing.qcow2 128M
  $ qemu-img create -f qcow2 -o backing_file=backing.qcow2 image.qcow2 6G
  $ qemu -drive if=virtio,cache=none,file=image.qcow2
  (qemu) block_stream virtio0
  (qemu) info block-jobs

The qemu-iotests 030 streaming test still passes.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-08-29 15:23:35 +02:00
Paolo Bonzini 6ef228fc0d stream: move rate limiting to a separate header file
Make the code reusable.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-06-15 14:03:42 +02:00
Paolo Bonzini 188a7bbf94 stream: move is_allocated_above to block.c
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-06-15 14:03:42 +02:00
Paolo Bonzini f9749f28b7 stream: tweak usage of bdrv_co_is_allocated
is_allocated_base has complex semantics that are not really usable
outside streaming.  Split the check in two parts, where the allocated
state for the top bs is moved to the caller.  The resulting function
is more generally useful.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-06-15 14:03:42 +02:00
Anthony Liguori 04120e3bb0 block: fix warning introduced in efcc7a23
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-05-10 09:10:42 -05:00
Paolo Bonzini efcc7a2324 stream: do not copy unallocated sectors from the base
Unallocated sectors should really never be accessed by the guest,
so there's no need to copy them during the streaming process.
If they are read by the guest during streaming, guest-initiated
copy-on-read will copy them (we're in the base == NULL case, which
enables copy on read).  If they are read after we disconnect the
image from the base, they will read as zeroes anyway.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-05-10 11:01:59 +02:00
Paolo Bonzini b21d677ee9 stream: fix ratelimiting corner case
This fixes inability to make progress in streaming if the quota is set
to less than the amount of data that an I/O operation has to write.

In this case, limit->dispatched + n will always be above the quota and,
due to the "goto retry" to recheck cancellation and allocation, streaming
will livelock.

This can be reproduced with "block_job_set_speed ide0-hd0 1b".  Of course,
with this patch the requested limit will not be obeyed.  That could be
done with another patch that caps is_allocated's n argument by the slice
quota.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-05-10 11:01:59 +02:00
Paolo Bonzini f6133def92 stream: pass new base image format to bdrv_change_backing_file
When an image is modified to point to the new backing file, the backing
file format is set to NULL, which means auto-probe.  This is wrong, in
fact it is a small security problem.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-05-10 11:01:59 +02:00
Paolo Bonzini fa4478d5c8 block: wait for job callback in block_job_cancel_sync
The limitation on not having I/O after cancellation cannot really be
kept.  Even streaming has a very small race window where you could
cancel a job and have it report completion.  If this window is hit,
bdrv_change_backing_file() will yield and possibly cause accesses to
dangling pointers etc.

So, let's just assume that we cannot know exactly what will happen
after the coroutine has set busy to false.  We can set a very lax
condition:

- if we cancel the job, the coroutine won't set it to false again
(and hence will not call co_sleep_ns again).

- block_job_cancel_sync will wait for the coroutine to exit, which
pretty much ensures no race.

Instead, we track the coroutine that executes the job and put very
strict conditions on what to do while it is quiescent (busy = false).
First of all, the coroutine must never set busy = false while the job
has been cancelled.  Second, the coroutine can be reentered arbitrarily
while it is quiescent, so you cannot really do anything but co_sleep_ns at
that time.  This condition is obeyed by the block_job_sleep_ns function.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-05-10 10:32:12 +02:00
Paolo Bonzini 4513eafe92 block: add block_job_sleep_ns
This function abstracts the pretty complex semantics of the "busy"
member of BlockJob.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-05-10 10:32:12 +02:00
Paolo Bonzini 469ef350e1 block: update in-memory backing file and format
These are needed to print "info block" output correctly.  QCOW2 does this
because it needs it to write the header, but QED does not, and common code
is the right place to do it.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-05-10 10:32:11 +02:00
Stefan Hajnoczi c83c66c3b5 block: add 'speed' optional parameter to block-stream
Allow streaming operations to be started with an initial speed limit.
This eliminates the window of time between starting streaming and
issuing block-job-set-speed.  Users should use the new optional 'speed'
parameter instead so that speed limits are in effect immediately when
the job starts.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-04-27 11:44:50 -03:00
Stefan Hajnoczi 882ec7ce53 block: change block-job-set-speed argument from 'value' to 'speed'
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-04-27 11:44:50 -03:00
Stefan Hajnoczi 9e6636c72d block: use Error mechanism instead of -errno for block_job_set_speed()
There are at least two different errors that can occur in
block_job_set_speed(): the job might not support setting speeds or the
value might be invalid.

Use the Error mechanism to report the error where it occurs.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-04-27 11:44:50 -03:00
Stefan Hajnoczi fd7f8c6537 block: use Error mechanism instead of -errno for block_job_create()
The block job API uses -errno return values internally and we convert
these to Error in the QMP functions.  This is ugly because the Error
should be created at the point where we still have all the relevant
information.  More importantly, it is hard to add new error cases to
this case since we quickly run out of -errno values without losing
information.

Go ahead and use Error directly and don't convert later.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-04-27 11:44:50 -03:00