Commit Graph

75 Commits

Author SHA1 Message Date
Kevin Wolf
a50c2ab858 job: Move state transitions to Job
This moves BlockJob.status and the closely related functions
(block_)job_state_transition() and (block_)job_apply_verb to Job. The
two QAPI enums are renamed to JobStatus and JobVerb.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-05-23 14:30:49 +02:00
John Snow
11b61fbc0d blockjobs: add block-job-finalize
Instead of automatically transitioning from PENDING to CONCLUDED, gate
the .prepare() and .commit() phases behind an explicit acknowledgement
provided by the QMP monitor if auto_finalize = false has been requested.

This allows us to perform graph changes in prepare and/or commit so that
graph changes do not occur autonomously without knowledge of the
controlling management layer.

Transactions that have reached the "PENDING" state together can all be
moved to invoke their finalization methods by issuing block_job_finalize
to any one job in the transaction.

Jobs in a transaction with mixed job->auto_finalize settings will all
remain stuck in the "PENDING" state, as if the entire transaction was
specified with auto_finalize = false. Jobs that specified
auto_finalize = true, however, will still not emit the PENDING event.

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19 12:01:24 +01:00
John Snow
35d6b368f2 blockjobs: ensure abort is called for cancelled jobs
Presently, even if a job is canceled post-completion as a result of
a failing peer in a transaction, it will still call .commit because
nothing has updated or changed its return code.

The reason why this does not cause problems currently is because
backup's implementation of .commit checks for cancellation itself.

I'd like to simplify this contract:

(1) Abort is called if the job/transaction fails
(2) Commit is called if the job/transaction succeeds

To this end: A job's return code, if 0, will be forcibly set as
-ECANCELED if that job has already concluded. Remove the now
redundant check in the backup job implementation.

We need to check for cancellation in both block_job_completed
AND block_job_completed_single, because jobs may be cancelled between
those two calls; for instance in transactions. This also necessitates
an ABORTING -> ABORTING transition to be allowed.

The check in block_job_completed could be removed, but there's no
point in starting to attempt to succeed a transaction that we know
in advance will fail.

This does NOT affect mirror jobs that are "canceled" during their
synchronous phase. The mirror job itself forcibly sets the canceled
property to false prior to ceding control, so such cases will invoke
the "commit" callback.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19 12:01:24 +01:00
John Snow
75f710599f blockjobs: add block_job_dismiss
For jobs that have reached their CONCLUDED state, prior to having their
last reference put down (meaning jobs that have completed successfully,
unsuccessfully, or have been canceled), allow the user to dismiss the
job's lingering status report via block-job-dismiss.

This gives management APIs the chance to conclusively determine if a job
failed or succeeded, even if the event broadcast was missed.

Note: block_job_do_dismiss and block_job_decommission happen to do
exactly the same thing, but they're called from different semantic
contexts, so both aliases are kept to improve readability.

Note 2: Don't worry about the 0x04 flag definition for AUTO_DISMISS, she
has a friend coming in a future patch to fill the hole where 0x02 is.

Verbs:
Dismiss: operates on CONCLUDED jobs only.
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19 12:01:24 +01:00
John Snow
0ec4dfb8d6 blockjobs: add block_job_verb permission table
Which commands ("verbs") are appropriate for jobs in which state is
also somewhat burdensome to keep track of.

As of this commit, it looks rather useless, but begins to look more
interesting the more states we add to the STM table.

A recurring theme is that no verb will apply to an 'undefined' job.

Further, it's not presently possible to restrict the "pause" or "resume"
verbs any more than they are in this commit because of the asynchronous
nature of how jobs enter the PAUSED state; justifications for some
seemingly erroneous applications are given below.

=====
Verbs
=====

Cancel:    Any state except undefined.
Pause:     Any state except undefined;
           'created': Requests that the job pauses as it starts.
           'running': Normal usage. (PAUSED)
           'paused':  The job may be paused for internal reasons,
                      but the user may wish to force an indefinite
                      user-pause, so this is allowed.
           'ready':   Normal usage. (STANDBY)
           'standby': Same logic as above.
Resume:    Any state except undefined;
           'created': Will lift a user's pause-on-start request.
           'running': Will lift a pause request before it takes effect.
           'paused':  Normal usage.
           'ready':   Will lift a pause request before it takes effect.
           'standby': Normal usage.
Set-speed: Any state except undefined, though ready may not be meaningful.
Complete:  Only a 'ready' job may accept a complete request.

=======
Changes
=======

(1)

To facilitate "nice" error checking, all five major block-job verb
interfaces in blockjob.c now support an errp parameter:

- block_job_user_cancel is added as a new interface.
- block_job_user_pause gains an errp paramter
- block_job_user_resume gains an errp parameter
- block_job_set_speed already had an errp parameter.
- block_job_complete already had an errp parameter.

(2)

block-job-pause and block-job-resume will no longer no-op when trying
to pause an already paused job, or trying to resume a job that isn't
paused. These functions will now report that they did not perform the
action requested because it was not possible.

iotests have been adjusted to address this new behavior.

(3)

block-job-complete doesn't worry about checking !block_job_started,
because the permission table guards against this.

(4)

test-bdrv-drain's job implementation needs to announce that it is
'ready' now, in order to be completed.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19 12:01:24 +01:00
John Snow
c9de40505f blockjobs: add state transition table
The state transition table has mostly been implied. We're about to make
it a bit more complex, so let's make the STM explicit instead.

Perform state transitions with a function that for now just asserts the
transition is appropriate.

Transitions:
Undefined -> Created: During job initialization.
Created   -> Running: Once the job is started.
                      Jobs cannot transition from "Created" to "Paused"
                      directly, but will instead synchronously transition
                      to running to paused immediately.
Running   -> Paused:  Normal workflow for pauses.
Running   -> Ready:   Normal workflow for jobs reaching their sync point.
                      (e.g. mirror)
Ready     -> Standby: Normal workflow for pausing ready jobs.
Paused    -> Running: Normal resume.
Standby   -> Ready:   Resume of a Standby job.

+---------+
|UNDEFINED|
+--+------+
   |
+--v----+
|CREATED|
+--+----+
   |
+--v----+     +------+
|RUNNING<----->PAUSED|
+--+----+     +------+
   |
+--v--+       +-------+
|READY<------->STANDBY|
+-----+       +-------+

Notably, there is no state presently defined as of this commit that
deals with a job after the "running" or "ready" states, so this table
will be adjusted alongside the commits that introduce those states.

Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-03-19 12:01:24 +01:00
Stefan Hajnoczi
d03654eacd block: let blk_add/remove_aio_context_notifier() tolerate BDS changes
Commit 2019ba0a01 ("block: Add AioContextNotifier functions to BB")
added blk_add/remove_aio_context_notifier() and implemented them by
passing through the bdrv_*() equivalent.

This doesn't work across bdrv_append(), which detaches child->bs and
re-attaches it to a new BlockDriverState.  When
blk_remove_aio_context_notifier() is called we will access the new BDS
instead of the one where the notifier was added!

>From the point of view of the blk_*() API user, changes to the root BDS
should be transparent.

This patch maintains a list of AioContext notifiers in BlockBackend and
adds/removes them from the BlockDriverState as needed.

Reported-by: Stefano Panella <spanella@gmail.com>
Cc: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20180306204819.11266-2-stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-13 15:38:55 -05:00
Fam Zheng
bdd6a90a9e block: Add VFIO based NVMe driver
This is a new protocol driver that exclusively opens a host NVMe
controller through VFIO. It achieves better latency than linux-aio by
completely bypassing host kernel vfs/block layer.

    $rw-$bs-$iodepth  linux-aio     nvme://
    ----------------------------------------
    randread-4k-1     10.5k         21.6k
    randread-512k-1   745           1591
    randwrite-4k-1    30.7k         37.0k
    randwrite-512k-1  1945          1980

    (unit: IOPS)

The driver also integrates with the polling mechanism of iothread.

This patch is co-authored by Paolo and me.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20180116060901.17413-4-famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
2018-02-08 09:22:03 +08:00
Eric Blake
7cfd527525 block: Make bdrv_round_to_clusters() signature more useful
In the process of converting sector-based interfaces to bytes,
I'm finding it easier to represent a byte count as a 64-bit
integer at the block layer (even if we are internally capped
by SIZE_MAX or even INT_MAX for individual transactions, it's
still nicer to not have to worry about truncation/overflow
issues on as many variables).  Update the signature of
bdrv_round_to_clusters() to uniformly use int64_t, matching
the signature already chosen for bdrv_is_allocated and the
fact that off_t is also a signed type, then adjust clients
according to the required fallout (even where the result could
now exceed 32 bits, no client is directly assigning the result
into a 32-bit value without breaking things into a loop first).

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-10-26 14:45:57 +02:00
Daniel P. Berrange
f42cf447e2 block: move trace probes into bdrv_co_preadv|pwritev
There are trace probes in bdrv_co_readv|writev, however, the
block drivers are being gradually moved over to using the
bdrv_co_preadv|pwritev functions instead. As a result some
block drivers miss the current probes. Move the probes
into bdrv_co_preadv|pwritev instead, so that they are triggered
by more (all?) I/O code paths.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170804105036.11879-1-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-07 09:39:35 +01:00
Vladimir Sementsov-Ogievskiy
8908eb1a4a trace-events: fix code style: print 0x before hex numbers
The only exception are groups of numers separated by symbols
'.', ' ', ':', '/', like 'ab.09.7d'.

This patch is made by the following:

> find . -name trace-events | xargs python script.py

where script.py is the following python script:
=========================
 #!/usr/bin/env python

import sys
import re
import fileinput

rhex = '%[-+ *.0-9]*(?:[hljztL]|ll|hh)?(?:x|X|"\s*PRI[xX][^"]*"?)'
rgroup = re.compile('((?:' + rhex + '[.:/ ])+' + rhex + ')')
rbad = re.compile('(?<!0x)' + rhex)

files = sys.argv[1:]

for fname in files:
    for line in fileinput.input(fname, inplace=True):
        arr = re.split(rgroup, line)
        for i in range(0, len(arr), 2):
            arr[i] = re.sub(rbad, '0x\g<0>', arr[i])

        sys.stdout.write(''.join(arr))
=========================

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Message-id: 20170731160135.12101-5-vsementsov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-01 12:13:07 +01:00
Vladimir Sementsov-Ogievskiy
db73ee4bc8 trace-events: fix code style: %# -> 0x%
In trace format '#' flag of printf is forbidden. Fix it to '0x%'.

This patch is created by the following:

check that we have a problem
> find . -name trace-events | xargs grep '%#' | wc -l
56

check that there are no cases with additional printf flags before '#'
> find . -name trace-events | xargs grep "%[-+ 0'I]+#" | wc -l
0

check that there are no wrong usage of '#' and '0x' together
> find . -name trace-events | xargs grep '0x%#' | wc -l
0

fix the problem
> find . -name trace-events | xargs sed -i 's/%#/0x%/g'

[Eric Blake noted that xargs grep '%[-+ 0'I]+#' should be xargs grep
"%[-+ 0'I]+#" instead so the shell quoting is correct.
--Stefan]

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170731160135.12101-3-vsementsov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-01 12:13:07 +01:00
Philippe Mathieu-Daudé
87e0331c5a docs: fix broken paths to docs/devel/tracing.txt
With the move of some docs/ to docs/devel/ on ac06724a71,
no references were updated.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-07-31 13:12:53 +03:00
Eric Blake
5cb1a49e01 trace: Show blockjob actions via bytes, not sectors
Upcoming patches are going to switch to byte-based interfaces
instead of sector-based.  Even worse, trace_backup_do_cow_enter()
had a weird mix of cluster and sector indices.

The trace interface is low enough that there are no stability
guarantees, and therefore nothing wrong with changing our units,
even in cases like trace_backup_do_cow_skip() where we are not
changing the trace output.  So make the tracing uniformly use
bytes.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-07-10 13:18:06 +02:00
Kevin Wolf
c5f1ad429c block: Remove bdrv_aio_readv/writev/flush()
These functions are unused now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-06-26 14:51:15 +02:00
Ashish Mittal
da92c3ff60 block/vxhs.c: Add support for a new block device type called "vxhs"
Source code for the qnio library that this code loads can be downloaded from:
https://github.com/VeritasHyperScale/libqnio.git

Sample command line using JSON syntax:
./x86_64-softmmu/qemu-system-x86_64 -name instance-00000008 -S -vnc 0.0.0.0:0
-k en-us -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5
-msg timestamp=on
'json:{"driver":"vxhs","vdisk-id":"c3e9095a-a5ee-4dce-afeb-2a59fb387410",
"server":{"host":"172.172.17.4","port":"9999"}}'

Sample command line using URI syntax:
qemu-img convert -f raw -O raw -n
/var/lib/nova/instances/_base/0c5eacd5ebea5ed914b6a3e7b18f1ce734c386ad
vxhs://192.168.0.1:9999/c6718f6b-0401-441d-a8c3-1f0064d75ee0

Sample command line using TLS credentials (run in secure mode):
./qemu-io --object
tls-creds-x509,id=tls0,dir=/etc/pki/qemu/vxhs,endpoint=client -c 'read
-v 66000 2.5k' 'json:{"server.host": "127.0.0.1", "server.port": "9999",
"vdisk-id": "/test.raw", "driver": "vxhs", "tls-creds":"tls0"}'

[Jeff: Modified trace-events with the correct string formatting]

Signed-off-by: Ashish Mittal <Ashish.Mittal@veritas.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 1491277689-24949-2-git-send-email-Ashish.Mittal@veritas.com
2017-04-24 15:08:42 -04:00
Stefan Hajnoczi
7f4076c1bb trace: clean up trace-events files
There are a number of unused trace events that
scripts/cleanup-trace-events.pl finds.  The "hw/vfio/pci-quirks.c"
filename was typoed and "qapi/qapi-visit-core.c" was missing the qapi/
directory prefix.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170126171613.1399-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-31 17:12:15 +00:00
Eric Blake
c1bb86cd8a block: Rename raw-{posix,win32} to file-*.c
These files deal with the file protocol, not the raw format (the
file protocol is often used with other formats, and the raw
format is not forced to use the file protocol).  Rename things
to make it a bit easier to follow.

Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-01-09 13:30:53 +01:00
John Snow
5ccac6f186 blockjob: add block_job_start
Instead of automatically starting jobs at creation time via backup_start
et al, we'd like to return a job object pointer that can be started
manually at later point in time.

For now, add the block_job_start mechanism and start the jobs
automatically as we have been doing, with conversions job-by-job coming
in later patches.

Of note: cancellation of unstarted jobs will perform all the normal
cleanup as if the job had started, particularly abort and clean. The
only difference is that we will not emit any events, because the job
never actually started.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1478587839-9834-5-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-14 22:47:34 -05:00
John Snow
8254b6d953 blockjob: centralize QMP event emissions
There's no reason to leave this to blockdev; we can do it in blockjobs
directly and get rid of an extra callback for most users.

All non-internal events, even those created outside of QMP, will
consistently emit events.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1477584421-1399-5-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-01 07:55:57 -04:00
Kevin Wolf
7381e95cc2 block: Remove bdrv_aio_pdiscard()
It is unused now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:22 +02:00
Laurent Vivier
e723b87103 trace-events: fix first line comment in trace-events
Documentation is docs/tracing.txt instead of docs/trace-events.txt.

find . -name trace-events -exec \
     sed -i "s?See docs/trace-events.txt for syntax documentation.?See docs/tracing.txt for syntax documentation.?" \
     {} \;

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-id: 1470669081-17860-1-git-send-email-lvivier@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-08-12 10:36:01 +01:00
Eric Blake
36e3b2e733 raw-posix: Switch paio_submit() to byte-based
The only remaining uses of paio_submit() were flush (with no
offset or count) and discard (which we are switching to byte-based);
furthermore, the similarly named paio_submit_co() is already
byte-based.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468624988-423-7-git-send-email-eblake@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20 14:11:55 +01:00
Eric Blake
60ebac16bc block: Convert bdrv_aio_discard() to byte-based
Another step towards byte-based interfaces everywhere.  Replace
the sector-based bdrv_aio_discard() with a new byte-based
bdrv_aio_pdiscard(), which silently ignores any unaligned head
or tail.  Driver callbacks will be converted in followup patches.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 1468624988-423-5-git-send-email-eblake@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-20 14:11:55 +01:00
Daniel P. Berrange
b54ca48e40 trace: split out trace events for block/ directory
Move all trace-events for files in the block/ directory to
their own file.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1466066426-16657-7-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-20 17:22:14 +01:00