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Author SHA1 Message Date
Markus Armbruster 992861fb1e error: Eliminate error_propagate() manually
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  The previous two commits did that for sufficiently simple
cases with Coccinelle.  Do it for several more manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-37-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster af175e85f9 error: Eliminate error_propagate() with Coccinelle, part 2
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  The previous commit did that with a Coccinelle script I
consider fairly trustworthy.  This commit uses the same script with
the matching of return taken out, i.e. we convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
    }

This is unsound: @err could still be read between afterwards.  I don't
know how to express "no read of @err without an intervening write" in
Coccinelle.  Instead, I manually double-checked for uses of @err.

Suboptimal line breaks tweaked manually.  qdev_realize() simplified
further to placate scripts/checkpatch.pl.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-36-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster 668f62ec62 error: Eliminate error_propagate() with Coccinelle, part 1
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }

where nothing else needs @err.  Coccinelle script:

    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }

    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }

    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err

Not exactly elegant, I'm afraid.

The "when != lbl:" is necessary to avoid transforming

         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);

even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().

Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.

The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().

Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.

Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster 235e59cf03 qemu-option: Use returned bool to check for failure
The previous commit enables conversion of

    foo(..., &err);
    if (err) {
        ...
    }

to

    if (!foo(..., &err)) {
        ...
    }

for QemuOpts functions that now return true / false on success /
error.  Coccinelle script:

    @@
    identifier fun = {
        opts_do_parse, parse_option_bool, parse_option_number,
        parse_option_size, qemu_opt_parse, qemu_opt_rename, qemu_opt_set,
        qemu_opt_set_bool, qemu_opt_set_number, qemu_opts_absorb_qdict,
        qemu_opts_do_parse, qemu_opts_from_qdict_entry, qemu_opts_set,
        qemu_opts_validate
    };
    expression list args, args2;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err, args2);
    -    if (err)
    +    if (!fun(args, &err, args2))
         {
             ...
         }

A few line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-15-armbru@redhat.com>
[Conflict with commit 0b6786a9c1 "block/amend: refactor qcow2 amend
options" resolved by rerunning Coccinelle on master's version]
2020-07-10 15:17:35 +02:00
Markus Armbruster c75d7f7191 qemu-option: Make functions taking Error ** return bool, not void
See recent commit "error: Document Error API usage rules" for
rationale.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-14-armbru@redhat.com>
2020-07-10 15:01:06 +02:00
Markus Armbruster c6ecec43b2 qemu-option: Check return value instead of @err where convenient
Convert uses like

    opts = qemu_opts_create(..., &err);
    if (err) {
        ...
    }

to

    opts = qemu_opts_create(..., errp);
    if (!opts) {
        ...
    }

Eliminate error_propagate() that are now unnecessary.  Delete @err
that are now unused.

Note that we can't drop parallels_open()'s error_propagate() here.  We
continue to execute it even in the converted case.  It's a no-op then:
local_err is null.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200707160613.848843-8-armbru@redhat.com>
2020-07-10 15:01:06 +02:00
Markus Armbruster a1b40bda08 blockdev: Deprecate -drive with bogus interface type
Drives with interface types other than if=none are for onboard
devices.  Unfortunately, any such drives the board doesn't pick up can
still be used with -device, like this:

    $ qemu-system-x86_64 -nodefaults -display none -S -drive if=floppy,id=bogus,unit=7 -device ide-cd,drive=bogus -monitor stdio
    QEMU 5.0.50 monitor - type 'help' for more information
    (qemu) info block
    bogus: [not inserted]
	Attached to:      /machine/peripheral-anon/device[0]
	Removable device: not locked, tray closed
    (qemu) info qtree
    bus: main-system-bus
      type System
      [...]
	    bus: ide.1
	      type IDE
	      dev: ide-cd, id ""
--->		drive = "bogus"
		[...]
		unit = 0 (0x0)
      [...]

This kind of abuse has always worked.  Deprecate it:

    qemu-system-x86_64: -drive if=floppy,id=bogus,unit=7: warning: bogus if=floppy is deprecated, use if=none

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200622094227.1271650-9-armbru@redhat.com>
2020-06-23 16:07:07 +02:00
Eric Blake bb4e58c613 blockdev: Split off basic bitmap operations for qemu-img
Upcoming patches want to add some basic bitmap manipulation abilities
to qemu-img.  But blockdev.o is too heavyweight to link into qemu-img
(among other things, it would drag in block jobs and transaction
support - qemu-img does offline manipulation, where atomicity is less
important because there are no concurrent modifications to compete
with), so it's time to split off the bare bones of what we will need
into a new file block/monitor/bitmap-qmp-cmds.o.

This is sufficient to expose 6 QMP commands for use by qemu-img (add,
remove, clear, enable, disable, merge), as well as move the three
helper functions touched in the previous patch.  Regarding
MAINTAINERS, the new file is automatically part of block core, but
also makes sense as related to other dirty bitmap files.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200513011648.166876-6-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2020-05-19 10:32:14 -05:00
Eric Blake c6996cf9a6 blockdev: Promote several bitmap functions to non-static
The next patch will split blockdev.c, which will require accessing
some previously-static functions from more than one .c file.  But part
of promoting a function to public is picking a naming scheme that does
not reek of exposing too many internals (two of the three functions
were named starting with 'do_').  To make future code motion easier,
perform the function rename and non-static promotion into its own
patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200513011648.166876-5-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2020-05-19 10:32:14 -05:00
Eric Blake a3aeeab557 block: Add blk_new_with_bs() helper
There are several callers that need to create a new block backend from
an existing BDS; make the task slightly easier with a common helper
routine.

Suggested-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200424190903.522087-2-eblake@redhat.com>
[mreitz: Set @ret only in error paths, see
 https://lists.nongnu.org/archive/html/qemu-block/2020-04/msg01216.html]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200428192648.749066-2-eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-05-05 13:17:36 +02:00
Kevin Wolf 8c6242b6f3 block-backend: Add flags to blk_truncate()
Now that node level interface bdrv_truncate() supports passing request
flags to the block driver, expose this on the BlockBackend level, too.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200424125448.63318-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-04-30 17:51:07 +02:00
Markus Armbruster 1f5842487a qapi: Only input visitors can actually fail
The previous few commits have made this more obvious, and removed the
one exception.  Time to clarify the documentation, and drop dead error
checking.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200424084338.26803-13-armbru@redhat.com>
2020-04-30 07:26:40 +02:00
Stefan Reiter b660a84bbb job: take each job's lock individually in job_txn_apply
All callers of job_txn_apply hold a single job's lock, but different
jobs within a transaction can have different contexts, thus we need to
lock each one individually before applying the callback function.

Similar to job_completed_txn_abort this also requires releasing the
caller's context before and reacquiring it after to avoid recursive
locks which might break AIO_WAIT_WHILE in the callback. This is safe, since
existing code would already have to take this into account, lest
job_completed_txn_abort might have broken.

This also brings to light a different issue: When a callback function in
job_txn_apply moves it's job to a different AIO context, callers will
try to release the wrong lock (now that we re-acquire the lock
correctly, previously it would just continue with the old lock, leaving
the job unlocked for the rest of the return path). Fix this by not caching
the job's context.

This is only necessary for qmp_block_job_finalize, qmp_job_finalize and
job_exit, since everyone else calls through job_exit.

One test needed adapting, since it calls job_finalize directly, so it
manually needs to acquire the correct context.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Message-Id: <20200407115651.69472-2-s.reiter@proxmox.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-04-07 14:34:47 +02:00
Kevin Wolf 30dd65f307 block: Fix cross-AioContext blockdev-snapshot
external_snapshot_prepare() tries to move the overlay to the AioContext
of the backing file (the snapshotted node). However, it's possible that
this doesn't work, but the backing file can instead be moved to the
overlay's AioContext (e.g. opening the backing chain for a mirror
target).

bdrv_append() already indirectly uses bdrv_attach_node(), which takes
care to move nodes to make sure they use the same AioContext and which
tries both directions.

So the problem has a simple fix: Just delete the unnecessary extra
bdrv_try_set_aio_context() call in external_snapshot_prepare() and
instead assert in bdrv_append() that both nodes were indeed moved to the
same AioContext.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200310113831.27293-6-kwolf@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-03-11 15:54:38 +01:00
Kevin Wolf d29d3d1f80 block: Relax restrictions for blockdev-snapshot
blockdev-snapshot returned an error if the overlay was already in use,
which it defined as having any BlockBackend parent. This is in fact both
too strict (some parents can tolerate the change of visible data caused
by attaching a backing file) and too loose (some non-BlockBackend
parents may not be happy with it).

One important use case that is prevented by the too strict check is live
storage migration with blockdev-mirror. Here, the target node is
usually opened without a backing file so that the active layer is
mirrored while its backing chain can be copied in the background.

The backing chain should be attached to the mirror target node when
finalising the job, just before switching the users of the source node
to the new copy (at which point the mirror job still has a reference to
the node). drive-mirror did this automatically, but with blockdev-mirror
this is the job of the QMP client, so it needs a way to do this.

blockdev-snapshot is the obvious way, so this patch makes it work in
this scenario. The new condition is that no parent uses CONSISTENT_READ
permissions. This will ensure that the operation will still be blocked
when the node is attached to the guest device, so blockdev-snapshot
remains safe.

(For the sake of completeness, x-blockdev-reopen can be used to achieve
the same, however it is a big hammer, performs the graph change
completely unchecked and is still experimental. So even with the option
of using x-blockdev-reopen, there are reasons why blockdev-snapshot
should be able to perform this operation.)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200310113831.27293-3-kwolf@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-03-11 15:54:38 +01:00
Maxim Levitsky 89802d5ae7 monitor/hmp: Move hmp_drive_add_node to block-hmp-cmds.c
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200308092440.23564-12-mlevitsk@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-09 18:20:22 +00:00
Maxim Levitsky a1edae276a monitor/hmp: move hmp_drive_del and hmp_commit to block-hmp-cmds.c
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200308092440.23564-5-mlevitsk@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-09 18:05:33 +00:00
Kevin Wolf 12c929bca2 block: Move system emulator QMP commands to block/qapi-sysemu.c
These commands make only sense for system emulators and their
implementations call functions that don't exist in tools (e.g. to
resolve qdev IDs). Move them out so that blockdev.c can be linked to
qemu-storage-daemon.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200224143008.13362-4-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-03-06 17:15:38 +01:00
Peter Krempa facda5443f qapi: Allow getting flat output from 'query-named-block-nodes'
When a management application manages node names there's no reason to
recurse into backing images in the output of query-named-block-nodes.

Add a parameter to the command which will return just the top level
structs.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Message-Id: <4470f8c779abc404dcf65e375db195cd91a80651.1579509782.git.pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[mreitz: Fixed coding style]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-02-20 16:43:42 +01:00
Max Reitz 7607074f42 blockdev: Allow resizing everywhere
Block nodes that do not allow resizing should not share BLK_PERM_RESIZE.
It does not matter whether they are the first non-filter in their chain
or not.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200218103454.296704-3-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-02-18 11:55:39 +01:00
Max Reitz ca08d937e8 blockdev: Allow external snapshots everywhere
There is no good reason why we would allow external snapshots only on
the first non-filter node in a chain.  Parent BDSs should not care
whether their child is replaced by a snapshot.  (If they do care, they
should announce that via freezing the chain, which is checked in
bdrv_append() through bdrv_set_backing_hd().)

Before we had bdrv_is_first_non_filter() here (since 212a5a8f09), there
was a special function bdrv_check_ext_snapshot() that allowed snapshots
by default, but block drivers could override this.  Only blkverify did
so, however.

It is not clear to me why blkverify would do so; maybe just so that the
testee block driver would not be replaced.  The introducing commit
f6186f49e2 does not explain why.  Maybe because 08b24cfe37 would have
been the correct solution?  (Which adds a .supports_backing check.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200218103454.296704-2-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-02-18 11:55:38 +01:00
Kevin Wolf 8faad1c7fb commit: Expose on-error option in QMP
Now that the error handling in the common block job is fixed, we can
expose the on-error option in QMP instead of hard-coding it as 'report'
in qmp_block_commit().

This fulfills the promise that the old comment in that function made,
even if a bit later than expected: "This will be part of the QMP
command, if/when the BlockdevOnError change for blkmirror makes it in".

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200214200812.28180-7-kwolf@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-02-18 10:53:56 +01:00
Aarushi Mehta f80f267373 blockdev: adds bdrv_parse_aio to use io_uring
Signed-off-by: Aarushi Mehta <mehta.aaru20@gmail.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200120141858.587874-8-stefanha@redhat.com
Message-Id: <20200120141858.587874-8-stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-01-30 20:59:41 +00:00
Sergio Lopez 377410f6fb blockdev: Return bs to the proper context on snapshot abort
external_snapshot_abort() calls to bdrv_set_backing_hd(), which
returns state->old_bs to the main AioContext, as it's intended to be
used then the BDS is going to be released. As that's not the case when
aborting an external snapshot, return it to the AioContext it was
before the call.

This issue can be triggered by issuing a transaction with two actions,
a proper blockdev-snapshot-sync and a bogus one, so the second will
trigger a transaction abort. This results in a crash with an stack
trace like this one:

 #0  0x00007fa1048b28df in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
 #1  0x00007fa10489ccf5 in __GI_abort () at abort.c:79
 #2  0x00007fa10489cbc9 in __assert_fail_base
     (fmt=0x7fa104a03300 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x5572240b44d8 "bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)", file=0x557224014d30 "block.c", line=2240, function=<optimized out>) at assert.c:92
 #3  0x00007fa1048aae96 in __GI___assert_fail
     (assertion=assertion@entry=0x5572240b44d8 "bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)", file=file@entry=0x557224014d30 "block.c", line=line@entry=2240, function=function@entry=0x5572240b5d60 <__PRETTY_FUNCTION__.31620> "bdrv_replace_child_noperm") at assert.c:101
 #4  0x0000557223e631f8 in bdrv_replace_child_noperm (child=0x557225b9c980, new_bs=new_bs@entry=0x557225c42e40) at block.c:2240
 #5  0x0000557223e68be7 in bdrv_replace_node (from=0x557226951a60, to=0x557225c42e40, errp=0x5572247d6138 <error_abort>) at block.c:4196
 #6  0x0000557223d069c4 in external_snapshot_abort (common=0x557225d7e170) at blockdev.c:1731
 #7  0x0000557223d069c4 in external_snapshot_abort (common=0x557225d7e170) at blockdev.c:1717
 #8  0x0000557223d09013 in qmp_transaction (dev_list=<optimized out>, has_props=<optimized out>, props=0x557225cc7d70, errp=errp@entry=0x7ffe704c0c98) at blockdev.c:2360
 #9  0x0000557223e32085 in qmp_marshal_transaction (args=<optimized out>, ret=<optimized out>, errp=0x7ffe704c0d08) at qapi/qapi-commands-transaction.c:44
 #10 0x0000557223ee798c in do_qmp_dispatch (errp=0x7ffe704c0d00, allow_oob=<optimized out>, request=<optimized out>, cmds=0x5572247d3cc0 <qmp_commands>) at qapi/qmp-dispatch.c:132
 #11 0x0000557223ee798c in qmp_dispatch (cmds=0x5572247d3cc0 <qmp_commands>, request=<optimized out>, allow_oob=<optimized out>) at qapi/qmp-dispatch.c:175
 #12 0x0000557223e06141 in monitor_qmp_dispatch (mon=0x557225c69ff0, req=<optimized out>) at monitor/qmp.c:120
 #13 0x0000557223e0678a in monitor_qmp_bh_dispatcher (data=<optimized out>) at monitor/qmp.c:209
 #14 0x0000557223f2f366 in aio_bh_call (bh=0x557225b9dc60) at util/async.c:117
 #15 0x0000557223f2f366 in aio_bh_poll (ctx=ctx@entry=0x557225b9c840) at util/async.c:117
 #16 0x0000557223f32754 in aio_dispatch (ctx=0x557225b9c840) at util/aio-posix.c:459
 #17 0x0000557223f2f242 in aio_ctx_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at util/async.c:260
 #18 0x00007fa10913467d in g_main_dispatch (context=0x557225c28e80) at gmain.c:3176
 #19 0x00007fa10913467d in g_main_context_dispatch (context=context@entry=0x557225c28e80) at gmain.c:3829
 #20 0x0000557223f31808 in glib_pollfds_poll () at util/main-loop.c:219
 #21 0x0000557223f31808 in os_host_main_loop_wait (timeout=<optimized out>) at util/main-loop.c:242
 #22 0x0000557223f31808 in main_loop_wait (nonblocking=<optimized out>) at util/main-loop.c:518
 #23 0x0000557223d13201 in main_loop () at vl.c:1828
 #24 0x0000557223bbfb82 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4504

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1779036
Signed-off-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-01-27 17:19:53 +01:00
Sergio Lopez 91005a495e blockdev: Acquire AioContext on dirty bitmap functions
Dirty map addition and removal functions are not acquiring to BDS
AioContext, while they may call to code that expects it to be
acquired.

This may trigger a crash with a stack trace like this one:

 #0  0x00007f0ef146370f in __GI_raise (sig=sig@entry=6)
     at ../sysdeps/unix/sysv/linux/raise.c:50
 #1  0x00007f0ef144db25 in __GI_abort () at abort.c:79
 #2  0x0000565022294dce in error_exit
     (err=<optimized out>, msg=msg@entry=0x56502243a730 <__func__.16350> "qemu_mutex_unlock_impl") at util/qemu-thread-posix.c:36
 #3  0x00005650222950ba in qemu_mutex_unlock_impl
     (mutex=mutex@entry=0x5650244b0240, file=file@entry=0x565022439adf "util/async.c", line=line@entry=526) at util/qemu-thread-posix.c:108
 #4  0x0000565022290029 in aio_context_release
     (ctx=ctx@entry=0x5650244b01e0) at util/async.c:526
 #5  0x000056502221cd08 in bdrv_can_store_new_dirty_bitmap
     (bs=bs@entry=0x5650244dc820, name=name@entry=0x56502481d360 "bitmap1", granularity=granularity@entry=65536, errp=errp@entry=0x7fff22831718)
     at block/dirty-bitmap.c:542
 #6  0x000056502206ae53 in qmp_block_dirty_bitmap_add
     (errp=0x7fff22831718, disabled=false, has_disabled=<optimized out>, persistent=<optimized out>, has_persistent=true, granularity=65536, has_granularity=<optimized out>, name=0x56502481d360 "bitmap1", node=<optimized out>) at blockdev.c:2894
 #7  0x000056502206ae53 in qmp_block_dirty_bitmap_add
     (node=<optimized out>, name=0x56502481d360 "bitmap1", has_granularity=<optimized out>, granularity=<optimized out>, has_persistent=true, persistent=<optimized out>, has_disabled=false, disabled=false, errp=0x7fff22831718) at blockdev.c:2856
 #8  0x00005650221847a3 in qmp_marshal_block_dirty_bitmap_add
     (args=<optimized out>, ret=<optimized out>, errp=0x7fff22831798)
     at qapi/qapi-commands-block-core.c:651
 #9  0x0000565022247e6c in do_qmp_dispatch
     (errp=0x7fff22831790, allow_oob=<optimized out>, request=<optimized out>, cmds=0x565022b32d60 <qmp_commands>) at qapi/qmp-dispatch.c:132
 #10 0x0000565022247e6c in qmp_dispatch
     (cmds=0x565022b32d60 <qmp_commands>, request=<optimized out>, allow_oob=<optimized out>) at qapi/qmp-dispatch.c:175
 #11 0x0000565022166061 in monitor_qmp_dispatch
     (mon=0x56502450faa0, req=<optimized out>) at monitor/qmp.c:145
 #12 0x00005650221666fa in monitor_qmp_bh_dispatcher
     (data=<optimized out>) at monitor/qmp.c:234
 #13 0x000056502228f866 in aio_bh_call (bh=0x56502440eae0)
     at util/async.c:117
 #14 0x000056502228f866 in aio_bh_poll (ctx=ctx@entry=0x56502440d7a0)
     at util/async.c:117
 #15 0x0000565022292c54 in aio_dispatch (ctx=0x56502440d7a0)
     at util/aio-posix.c:459
 #16 0x000056502228f742 in aio_ctx_dispatch
     (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at util/async.c:260
 #17 0x00007f0ef5ce667d in g_main_dispatch (context=0x56502449aa40)
     at gmain.c:3176
 #18 0x00007f0ef5ce667d in g_main_context_dispatch
     (context=context@entry=0x56502449aa40) at gmain.c:3829
 #19 0x0000565022291d08 in glib_pollfds_poll () at util/main-loop.c:219
 #20 0x0000565022291d08 in os_host_main_loop_wait
     (timeout=<optimized out>) at util/main-loop.c:242
 #21 0x0000565022291d08 in main_loop_wait (nonblocking=<optimized out>)
     at util/main-loop.c:518
 #22 0x00005650220743c1 in main_loop () at vl.c:1828
 #23 0x0000565021f20a72 in main
     (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>)
     at vl.c:4504

Fix this by acquiring the AioContext at qmp_block_dirty_bitmap_add()
and qmp_block_dirty_bitmap_add().

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1782175
Signed-off-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-01-27 17:19:53 +01:00
Sergio Lopez 3ea67e0883 blockdev: honor bdrv_try_set_aio_context() context requirements
bdrv_try_set_aio_context() requires that the old context is held, and
the new context is not held. Fix all the occurrences where it's not
done this way.

Suggested-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-01-27 17:19:53 +01:00
Sergio Lopez 5b7bfe515e blockdev: unify qmp_blockdev_backup and blockdev-backup transaction paths
Issuing a blockdev-backup from qmp_blockdev_backup takes a slightly
different path than when it's issued from a transaction. In the code,
this is manifested as some redundancy between do_blockdev_backup() and
blockdev_backup_prepare().

This change unifies both paths, merging do_blockdev_backup() and
blockdev_backup_prepare(), and changing qmp_blockdev_backup() to
create a transaction instead of calling do_backup_common() direcly.

As a side-effect, now qmp_blockdev_backup() is executed inside a
drained section, as it happens when creating a blockdev-backup
transaction. This change is visible from the user's perspective, as
the job gets paused and immediately resumed before starting the actual
work.

Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-01-27 17:19:53 +01:00
Sergio Lopez 2288ccfac9 blockdev: unify qmp_drive_backup and drive-backup transaction paths
Issuing a drive-backup from qmp_drive_backup takes a slightly
different path than when it's issued from a transaction. In the code,
this is manifested as some redundancy between do_drive_backup() and
drive_backup_prepare().

This change unifies both paths, merging do_drive_backup() and
drive_backup_prepare(), and changing qmp_drive_backup() to create a
transaction instead of calling do_backup_common() direcly.

As a side-effect, now qmp_drive_backup() is executed inside a drained
section, as it happens when creating a drive-backup transaction. This
change is visible from the user's perspective, as the job gets paused
and immediately resumed before starting the actual work.

Also fix tests 141, 185 and 219 to cope with the extra
JOB_STATUS_CHANGE lines.

Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-01-27 17:19:53 +01:00
Sergio Lopez 471ded690e blockdev: fix coding style issues in drive_backup_prepare
Fix a couple of minor coding style issues in drive_backup_prepare.

Signed-off-by: Sergio Lopez <slp@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-01-27 17:19:53 +01:00
Max Reitz c80d8b06cf block: Add @exact parameter to bdrv_co_truncate()
We have two drivers (iscsi and file-posix) that (in some cases) return
success from their .bdrv_co_truncate() implementation if the block
device is larger than the requested offset, but cannot be shrunk.  Some
callers do not want that behavior, so this patch adds a new parameter
that they can use to turn off that behavior.

This patch just adds the parameter and lets the block/io.c and
block/block-backend.c functions pass it around.  All other callers
always pass false and none of the implementations evaluate it, so that
this patch does not change existing behavior.  Future patches take care
of that.

Suggested-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190918095144.955-5-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-28 12:00:07 +01:00
Kevin Wolf 46741111ba blockdev: Use error_report() in hmp_commit()
Instead of using monitor_printf() to report errors, hmp_commit() should
use error_report() like other places do.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-10-25 15:15:01 +02:00
John Snow 3264ffced3 dirty-bitmaps: remove deprecated autoload parameter
This parameter has been deprecated since 2.12.0 and is eligible for
removal. Remove this parameter as it is actually completely ignored;
let's not give false hope.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191002232411.29968-1-jsnow@redhat.com
2019-10-17 17:53:28 -04:00
Vladimir Sementsov-Ogievskiy 5deb6cbd1f block/dirty-bitmap: add bs link
Add bs field to BdrvDirtyBitmap structure. Drop BlockDriverState
parameter from bitmap APIs where possible.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190916141911.5255-3-vsementsov@virtuozzo.com
[Rebased on top of block-copy. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy d2c3080e41 block/qcow2: proper locking on bitmap add/remove paths
qmp_block_dirty_bitmap_add and do_block_dirty_bitmap_remove do acquire
aio context since 0a6c86d024. But this is not enough: we also must
lock qcow2 mutex when access in-image metadata. Especially it concerns
freeing qcow2 clusters.

To achieve this, move qcow2_can_store_new_dirty_bitmap and
qcow2_remove_persistent_dirty_bitmap to coroutine context.

Since we work in coroutines in correct aio context, we don't need
context acquiring in blockdev.c anymore, drop it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190920082543.23444-4-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy b56a1e3175 block/dirty-bitmap: return int from bdrv_remove_persistent_dirty_bitmap
It's more comfortable to not deal with local_err.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190920082543.23444-3-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-10-17 17:02:32 -04:00
Vladimir Sementsov-Ogievskiy 00e30f05de block/backup: use backup-top instead of write notifiers
Drop write notifiers and use filter node instead.

= Changes =

1. Add filter-node-name argument for backup qmp api. We have to do it
in this commit, as 257 needs to be fixed.

2. There are no more write notifiers here, so is_write_notifier
parameter is dropped from block-copy paths.

3. To sync with in-flight requests at job finish we now have drained
removing of the filter, we don't need rw-lock.

4. Block-copy is now using BdrvChildren instead of BlockBackends

5. As backup-top owns these children, we also move block-copy state
into backup-top's ownership.

= Iotest changes =

56: op-blocker doesn't shoot now, as we set it on source, but then
check on filter, when trying to start second backup.
To keep the test we instead can catch another collision: both jobs will
get 'drive0' job-id, as job-id parameter is unspecified. To prevent
interleaving with file-posix locks (as they are dependent on config)
let's use another target for second backup.

Also, it's obvious now that we'd like to drop this op-blocker at all
and add a test-case for two backups from one node (to different
destinations) actually works. But not in these series.

141: Output changed: prepatch, "Node is in use" comes from bdrv_has_blk
check inside qmp_blockdev_del. But we've dropped block-copy blk
objects, so no more blk objects on source bs (job blk is on backup-top
filter bs). New message is from op-blocker, which is the next check in
qmp_blockdev_add.

257: The test wants to emulate guest write during backup. They should
go to filter node, not to original source node, of course. Therefore we
need to specify filter node name and use it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-6-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00
Max Reitz cdf3bc934a mirror: Fix bdrv_has_zero_init() use
bdrv_has_zero_init() only has meaning for newly created images or image
areas.  If the mirror job itself did not create the image, it cannot
rely on bdrv_has_zero_init()'s result to carry any meaning.

This is the case for drive-mirror with mode=existing and always for
blockdev-mirror.

Note that we only have to zero-initialize the target with sync=full,
because other modes actually do not promise that the target will contain
the same data as the source after the job -- sync=top only promises to
copy anything allocated in the top layer, and sync=none will only copy
new I/O.  (Which is how mirror has always handled it.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190724171239.8764-3-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-08-19 17:13:26 +02:00
Vladimir Sementsov-Ogievskiy 319bd5edb9 block/backup: deal with zero detection
We have detect_zeroes option, so at least for blockdev-backup user
should define it if zero-detection is needed. For drive-backup leave
detection enabled by default but do it through existing option instead
of open-coding.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190730163251.755248-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 18:29:43 -04:00
John Snow 1a2b8b406b block/backup: support bitmap sync modes for non-bitmap backups
Accept bitmaps and sync policies for the other backup modes.
This allows us to do things like create a bitmap synced to a full backup
without a transaction, or start a resumable backup process.

Some combinations don't make sense, though:

- NEVER policy combined with any non-BITMAP mode doesn't do anything,
  because the bitmap isn't used for input or output.
  It's harmless, but is almost certainly never what the user wanted.

- sync=NONE is more questionable. It can't use on-success because this
  job never completes with success anyway, and the resulting artifact
  of 'always' is suspect: because we start with a full bitmap and only
  copy out segments that get written to, the final output bitmap will
  always be ... a fully set bitmap.

  Maybe there's contexts in which bitmaps make sense for sync=none,
  but not without more severe changes to the current job, and omitting
  it here doesn't prevent us from adding it later.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-11-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 18:29:43 -04:00
John Snow a6c9365ad4 block/backup: hoist bitmap check into QMP interface
This is nicer to do in the unified QMP interface that we have now,
because it lets us use the right terminology back at the user.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190716000117.25219-5-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
John Snow c4e4b0fa59 qapi: implement block-dirty-bitmap-remove transaction action
It is used to do transactional movement of the bitmap (which is
possible in conjunction with merge command). Transactional bitmap
movement is needed in scenarios with external snapshot, when we don't
want to leave copy of the bitmap in the base image.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190708220502.12977-3-jsnow@redhat.com
[Edited "since" version to 4.2 --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:03 -04:00
Vladimir Sementsov-Ogievskiy 2899f41eef blockdev: reduce aio_context locked sections in bitmap add/remove
Commit 0a6c86d024 returned these locks back to add/remove
functionality, to protect from intersection of persistent bitmap
related IO with other IO. But other bitmap-related functions called
here are unrelated to the problem, and there are no needs to keep these
calls inside critical sections.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190708220502.12977-2-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow b30ffbef53 block/backup: loosen restriction on readonly bitmaps
With the "never" sync policy, we actually can utilize readonly bitmaps
now. Loosen the check at the QMP level, and tighten it based on
provided arguments down at the job creation level instead.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-19-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow c8b5650178 block/backup: Add mirror sync mode 'bitmap'
We don't need or want a new sync mode for simple differences in
semantics.  Create a new mode simply named "BITMAP" that is designed to
make use of the new Bitmap Sync Mode field.

Because the only bitmap sync mode is 'on-success', this adds no new
functionality to the backup job (yet). The old incremental backup mode
is maintained as a syntactic sugar for sync=bitmap, mode=on-success.

Add all of the plumbing necessary to support this new instruction.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-6-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:02 -04:00
John Snow 9203056614 blockdev-backup: utilize do_backup_common
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:01 -04:00
John Snow 7b0b870bcc drive-backup: create do_backup_common
Create a common core that comprises the actual meat of what the backup API
boundary needs to do, and then switch drive-backup to use it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
2019-08-16 16:28:01 -04:00
Markus Armbruster 54d31236b9 sysemu: Split sysemu/runstate.h off sysemu/sysemu.h
sysemu/sysemu.h is a rather unfocused dumping ground for stuff related
to the system-emulator.  Evidence:

* It's included widely: in my "build everything" tree, changing
  sysemu/sysemu.h still triggers a recompile of some 1100 out of 6600
  objects (not counting tests and objects that don't depend on
  qemu/osdep.h, down from 5400 due to the previous two commits).

* It pulls in more than a dozen additional headers.

Split stuff related to run state management into its own header
sysemu/runstate.h.

Touching sysemu/sysemu.h now recompiles some 850 objects.  qemu/uuid.h
also drops from 1100 to 850, and qapi/qapi-types-run-state.h from 4400
to 4200.  Touching new sysemu/runstate.h recompiles some 500 objects.

Since I'm touching MAINTAINERS to add sysemu/runstate.h anyway, also
add qemu/main-loop.h.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-30-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[Unbreak OS-X build]
2019-08-16 13:37:36 +02:00
Markus Armbruster db72581598 Include qemu/main-loop.h less
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).  It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.

Include qemu/main-loop.h only where it's needed.  Touching it now
recompiles only some 1700 objects.  For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800.  For the
others, they shrink only slightly.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Vladimir Sementsov-Ogievskiy 85c9d133fb blockdev: enable non-root nodes for transaction drive-backup source
We forget to enable it for transaction .prepare, while it is already
enabled in do_drive_backup since commit a2d665c1bc
    "blockdev: loosen restrictions on drive-backup source node"

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190618140804.59214-1-vsementsov@virtuozzo.com
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-06-24 15:53:01 +02:00
Vladimir Sementsov-Ogievskiy b23c580c94 block: drop bs->job
Drop remaining users of bs->job:
1. assertions actually duplicated by assert(!bs->refcnt)
2. trace-point seems not enough reason to change stream_start to return
   BlockJob pointer
3. Restricting creation of two jobs based on same bs is bad idea, as
   3.1 Some jobs creates filters to be their main node, so, this check
   don't actually prevent creating second job on same real node (which
   will create another filter node) (but I hope it is restricted by
   other mechanisms)
   3.2 Even without bs->job we have two systems of permissions:
   op-blockers and BLK_PERM
   3.3 We may want to run several jobs on one node one day

And finally, drop bs->job pointer itself. Hurrah!

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-18 16:41:10 +02:00