Instead of propagating any change of a BDS's AioContext only to its file
and backing children and letting driver-specific code do the rest, just
propagate it to all and drop the thus superfluous implementations of
bdrv_{at,de}tach_aio_context() in Quorum, blkverify and VMDK.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch removes the remaining users of bs->blk, which will allow us
to have multiple BBs on top of a single BDS. In the meantime, all checks
that are currently in place to prevent the user from creating such
setups can be switched to bdrv_has_blk() instead of accessing BDS.blk.
Future patches can allow them and e.g. enable users to mirror to a block
device that already has a BlockBackend on it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
We need to introduce a separate BdrvNextIterator struct that can keep
more state than just the current BDS in order to avoid using the bs->blk
pointer.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
In order to get rid of bs->blk for bdrv_get_device_name() and
bdrv_get_device_or_node_name(), ask all parents for their name and
simply pick the first one.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
We want to get rid of BlockDriverState.blk in order to allow multiple
BlockBackends per BDS. Converting the device callbacks in block.c (which
assume a single BlockBackend) to per-child callbacks gets us rid of the
first few instances.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This reverts commit 76b223200e.
Now that I/O throttling is fully done on the BlockBackend level, there
is no reason any more to block I/O throttling for nodes with multiple
parents as the parents don't influence each other any more.
Conflicts:
block.c
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_move_feature_fields() and swap_feature_fields() are empty now, they
can be removed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
This moves the throttling related part of the BDS life cycle management
to BlockBackend. The throttling group reference is now kept even when no
medium is inserted.
With this commit, throttling isn't disabled and then re-enabled any more
during graph reconfiguration. This fixes the temporary breakage of I/O
throttling when used with live snapshots or block jobs that manipulate
the graph.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch changes where the throttling state is stored (used to be the
BlockDriverState, now it is the BlockBackend), but it doesn't actually
make it a BB level feature yet. For example, throttling is still
disabled when the BDS is detached from the BB.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
It was already true in principle that a throttled BDS always has a BB
attached, except that the order of operations while attaching or
detaching a BDS to/from a BB wasn't careful enough.
This commit breaks graph manipulations while I/O throttling is enabled.
It would have been possible to keep things working with some temporary
hacks, but quite cumbersome, so it's not worth the hassle. We'll fix
things again in a minute.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
In some cases, we want to take a quorum child offline, and take
another child online.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1462865799-19402-2-git-send-email-xiecl.fnst@cn.fujitsu.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Currently we only inactivate the top BDS. Actually bdrv_inactivate
should be the opposite of bdrv_invalidate_cache.
Recurse into the whole subtree instead.
Because a node may have multiple parents, and because once
BDRV_O_INACTIVE is set for a node, further writes are not allowed, we
cannot interleave flag settings and .bdrv_inactivate calls (that may
submit write to other nodes in a graph) within a single pass. Therefore
two passes are used here.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently we only recurse to bs->file, which will miss the children in quorum
and VMDK.
Recurse into the whole subtree to avoid that.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There are no block drivers left that implement the old .bdrv_read/write
interface, so it can be removed now. This gets us rid of the
corresponding emulation functions, too.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Extract the handling of throttling from bdrv_flush_io_queue. These
new functions will soon become BdrvChildRole callbacks, as they can
be generalized to "beginning of drain" and "end of drain".
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
As the patches to move I/O throttling to BlockBackend didn't make it in
time for the 2.6 release, but the release adds new ways of configuring
VMs whose behaviour would change once the move is done, we need to
outlaw such configurations temporarily.
The problem exists whenever a BDS has more users than just its BB, for
example it is used as a backing file for another node. (This wasn't
possible in 2.5 yet as we introduced node references to specify a
backing file only recently.) In these cases, the throttling would
apply to these other users now, but after moving throttling to the
BlockBackend the other users wouldn't be throttled any more.
This patch prevents making new references to a throttled node as well as
using monitor commands to throttle a node with multiple parents.
Compared to 2.5 this changes behaviour in some corner cases where
references were allowed before, like bs->file or Quorum children. It
seems reasonable to assume that users didn't use I/O throttling on such
low level nodes. With the upcoming move of throttling into BlockBackend,
such configurations won't be possible anyway.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The only remaining users were block jobs (mirror and backup) which
unconditionally enabled WCE on the BlockBackend of the target image. As
these block jobs don't go through BlockBackend for their I/O requests,
they aren't affected by this setting anyway but always get a writeback
mode, so that call can be removed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The previous patches have successively made blk->enable_write_cache the
true source for the information whether a writethrough mode must be
implemented. The corresponding BDRV_O_CACHE_WB is only useless baggage
we're carrying around, so now's the time to remove it.
At the same time, we remove the 'cache.writeback' option parsing on the
BDS level as the only effect was setting the BDRV_O_CACHE_WB flag.
This change requires test cases that explicitly enabled the option to
drop it. Other than that and the change of the error message when
writethrough is enabled on the BDS level (from "Can't set writethrough
mode" to "doesn't support the option"), there should be no change in
behaviour.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
We must forbid changing the WCE flag in bdrv_reopen() in the same patch,
as otherwise the behaviour would change so that the flag takes
precedence over the explicitly specified option.
The correct value of the WCE flag depends on the BlockBackend user (e.g.
guest device) and isn't a decision that the QMP client makes, so this
change is what we want.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Now that WCE is handled on the BlockBackend level, the flag is
meaningless for BDSes. As the schema requires us to fill the field,
we return an enabled write cache for them.
Note that this means that querying the BlockBackend name may return
writethrough as the cache information, whereas querying the node-name of
the root of that same BlockBackend will return writeback.
This may appear odd at first, but it actually makes sense because it
correctly repesents the layer that implements the WCE handling. This
becomes more apparent when you consider nodes that are the root node of
multiple BlockBackends, where each BB can have its own WCE setting.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Whether a write cache is used or not is a decision that concerns the
user (e.g. the guest device) rather than the backend. It was already
logically part of the BB level as bdrv_move_feature_fields() always kept
it on top of the BDS tree; with this patch, the core of it (the actual
flag and the additional flushes) is also implemented there.
Direct callers of bdrv_open() must pass BDRV_O_CACHE_WB now if bs
doesn't have a BlockBackend attached.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
It's like bdrv_parse_cache_flags(), except that writethrough mode isn't
included in the flags, but returned as a separate bool.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
For a couple of releases we have been warning
Encrypted images are deprecated
Support for them will be removed in a future release.
You can use 'qemu-img convert' to convert your image to an unencrypted one.
This warning was issued by system emulators, qemu-img, qemu-nbd
and qemu-io. Such a broad warning was issued because the original
intention was to rip out all the code for dealing with encryption
inside the QEMU block layer APIs.
The new block encryption framework used for the LUKS driver does
not rely on the unloved block layer API for encryption keys,
instead using the QOM 'secret' object type. It is thus no longer
appropriate to warn about encryption unconditionally.
When the qcow/qcow2 drivers are converted to use the new encryption
framework too, it will be practical to keep AES-CBC support present
for use in qemu-img, qemu-io & qemu-nbd to allow for interoperability
with older QEMU versions and liberation of data from existing encrypted
qcow2 files.
This change moves the warning out of the generic block code and
into the qcow/qcow2 drivers. Further, the warning is set to only
appear when running the system emulators, since qemu-img, qemu-io,
qemu-nbd are expected to support qcow2 encryption long term now that
the maint burden has been eliminated.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When opening an image it is useful to know whether the caller
intends to perform I/O on the image or not. In the case of
encrypted images this will allow the block driver to avoid
having to prompt for decryption keys when we merely want to
query header metadata about the image. eg qemu-img info
This flag is enforced at the top level only, since even if
we don't want todo I/O on the 'qcow2' file payload, the
underlying 'file' driver will still need todo I/O to read
the qcow2 header, for example.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Writethrough mode is going to become a BlockBackend feature rather than
a BDS one, so forbid it in places where we won't be able to support it
when the code finally matches the envisioned design.
We only allowed setting the cache mode of non-root nodes after the 2.5
release, so we're still free to make this change.
The target of block jobs is now always opened in a writeback mode
because it doesn't have a BlockBackend attached. This makes more sense
anyway because block jobs know when to flush. If the graph is modified
on job completion, the original cache mode moves to the new root, so
for the guest device writethough always stays enabled if it was
configured this way.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
First of all, we're generally not writing to backing files, but when we
do, it's in the context of block jobs which know very well when to flush
the image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This patch changes dirty bitmaps from following a BlockBackend in graph
changes to sticking with the node they were created at. For the full
discussion, read the following mailing list thread:
[Qemu-block] block: Dirty bitmaps and COR in bdrv_move_feature_fields()
https://lists.nongnu.org/archive/html/qemu-block/2016-02/msg00745.html
In summary, the justification for this change is:
* When moving the dirty bitmap to the top of the tree was introduced in
bdrv_append() in commit a9fc4408, it didn't actually have any effect
because there could never be a bitmap in use when bdrv_append() was
called (op blockers would prevent this). This is still true today for
all internal uses of dirty bitmaps.
* Support for user-defined dirty bitmaps was introduced in 2.4, but we
discouraged users from using it because we didn't consider it ready
yet.
Moreover, in 2.5, the bdrv_swap() removal introduced a bug that left
dangling pointers if a dirty bitmap was present (the anchors of the
dirty bitmap were swapped, but the back link in the first element
wasn't updated), so it didn't even work correctly.
* block-dirty-bitmap-add takes an arbitrary node name, even if no
BlockBackend is attached. This suggests that it is a node level
operation and not a BlockBackend one. Consequently, there is no reason
for dirty bitmaps to stay with a BlockBackend that was attached to the
node they were created for.
* It was suggested that block-dirty-bitmap-add could track the node if a
node name was specified, and track the BlockBackend if the device name
was specified. This would however be inconsistent with other QMP
commands. Commands that accept both device and node names currently
interpret the device name just as an alias for the current root node
of that BlockBackend.
* Dirty bitmaps have a name that is only unique amongst the bitmaps in a
specific node. Moving bitmaps could lead to name clashes. Automatic
renaming would involve too much magic.
* Persistent bitmaps are stored in a specific node. Moving them around
automatically might be at least surprising, but it would probably also
become a real problem because that would have to happen atomically
without the management tool knowing of the operation.
At the end of the day it seems to be very clear that it was a mistake to
include dirty bitmaps in bdrv_move_feature_fields(). The functionality
of moving bitmaps and/or attaching them to a BlockBackend instead will
probably be needed, but it should be done with a new explicit QMP
command or option.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Ever since we first introduced bdrv_append() in commit 8802d1fd ('qapi:
Introduce blockdev-group-snapshot-sync command'), the copy-on-read flag
was moved to the new top layer when taking a snapshot. The only problem
is that it doesn't make a whole lot of sense.
The use case for manually enabled CoR is to avoid reading data twice
from a slow remote image, so we want to save it to a local overlay, say
an ISO image accessed via HTTP to a local qcow2 overlay. When taking a
snapshot, we end up with a backing chain like this:
http <- local.qcow2 <- snap_overlay.qcow2
There is no point in doing CoR from local.qcow2 into snap_overlay.qcow2,
we just want to keep copying data from the remote source into
local.qcow2.
The other use case of CoR is in the context of streaming, which isn't
very interesting for bdrv_move_feature_fields() because op blockers
prevent this combination.
This patch makes the copy-on-read flag stay on the image for which it
was originally set and prevents it from being propagated to the new
overlay. It is no longer intended to move CoR to the BlockBackend level.
In order for this to make sense, we also need to keep the respective
image read-write.
As a side effect of these changes, creating a live snapshot image (as
opposed to using an existing externally created one) on top of a COR
block device works now. It used to fail because it tried to open its
backing file both read-only and with COR.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The call in hmp_drive_del() is dead code because blk_remove_bs() is
called a few lines above. The only other remaining user is
bdrv_delete(), which only abuses bdrv_make_anon() to remove it from the
named nodes list. This path inlines the list entry removal into
bdrv_delete() and removes bdrv_make_anon().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)
Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There is no point in manually iterating through the bdrv_states list
when there is bdrv_next().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Instead of using the bdrv_states list, iterate over all the
BlockDriverStates attached to BlockBackends, and over all the
monitor-owned BDSs afterwards (except for those attached to a BB).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Move bdrv_commit_all() and bdrv_flush_all() to the BlockBackend level.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The information which BB is concerned does not seem useful enough to
justify its existence in most other place (which may be related to qemu
printing the -drive parameter in question anyway, and for blockdev-add
the attribution is naturally unambiguous). Furthermore, as of a future
patch, bdrv_get_device_name(bs) will always return the empty string
before bdrv_open_inherit() returns.
Therefore, just dropping that information seems to be the best course of
action.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The only code change is making bdrv_dirty_bitmap_truncate public. It is
used in block.c.
Also two long lines (bdrv_get_dirty) are wrapped.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1457412306-18940-5-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Since commit 91a097e, we end up with a somewhat weird cache mode
configuration with snapshot=on: The commit broke the cache mode
inheritance for the snapshot overlay so that it is opened as
writethrough instead of unsafe now. The following bdrv_append() call to
put it on top of the tree swaps the WCE flag with the snapshot's backing
file (i.e. the originally given file), so what we eventually get is
cache=writeback on the temporary overlay and
cache=writethrough,cache.no-flush=on on the real image file.
This patch changes things so that the temporary overlay gets
cache=unsafe again like it used to, and the real images get whatever the
user specified. This means that cache.direct is now respected even with
snapshot=on, and in the case of committing changes, the final flush is
no longer ignored except explicitly requested by the user.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The BDRV_O_INACTIVE flag should only be set for images explicitly opened
by the user. snapshot=on needs to create a new qcow2 image and write
some metadata to it. This is not a problem because it can't come from
the source, so there's no reason to mark it as BDRV_O_INACTIVE, even
though it is opened while waiting for the migration to complete.
This fixes an assertion failure when -incoming and snapshot=on are
combined.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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>
Message-id: 1454089805-5470-16-git-send-email-peter.maydell@linaro.org
This fixes a regression introduced with commit 3f09bfbc7. Multiple
bugs arise in conjunction with live snapshots and mirroring operations
(which include active layer commit).
After a live snapshot occurs, the active layer and the base layer both
have a non-NULL tqe_prev field in the device_list, although the base
node's tqe_prev field points to a NULL entry. This non-NULL tqe_prev
field occurs after the bdrv_append() in the external snapshot calls
change_parent_backing_link().
In change_parent_backing_link(), when the previous active layer is
removed from device_list, the device_list.tqe_prev pointer is not
set to NULL.
The operating scheme in the block layer is to indicate that a BDS belongs
in the bdrv_states device_list iff the device_list.tqe_prev pointer
is non-NULL.
This patch does two things:
1.) Introduces a new block layer helper bdrv_device_remove() to remove a
BDS from the device_list, and
2.) uses that new API, which also fixes the regression once used in
change_parent_backing_link().
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 0cd51e11c0666c04ddb7c05293fe94afeb551e89.1454376655.git.jcody@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This patch rewrites bdrv_close_all(): Until now, all root BDSs have been
force-closed. This is bad because it can lead to cached data not being
flushed to disk.
Instead, try to make all reference holders relinquish their reference
voluntarily:
1. All BlockBackend users are handled by making all BBs simply eject
their BDS tree. Since a BDS can never be on top of a BB, this will
not cause any of the issues as seen with the force-closing of BDSs.
The references will be relinquished and any further access to the BB
will fail gracefully.
2. All BDSs which are owned by the monitor itself (because they do not
have a BB) are relinquished next.
3. Besides BBs and the monitor, block jobs and other BDSs are the only
things left that can hold a reference to BDSs. After every remaining
block job has been canceled, there should not be any BDSs left (and
the loop added here will always terminate (as long as NDEBUG is not
defined), because either all_bdrv_states will be empty or there will
not be any block job left to cancel, failing the assertion).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We need this list so that bdrv_close_all() can keep track of which BDSs
are still open after having removed the BDSs from all of the BBs and
having released all monitor BDS references.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There are no users of bdrv_close() left, except for one of bdrv_open()'s
failure paths, bdrv_close_all() and bdrv_delete(), and that is good.
Make bdrv_close() static so nobody makes the mistake of directly using
bdrv_close() again.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is unused now, so we can remove it.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_delete() is not very happy about deleting BlockDriverStates with
dirty bitmaps still attached to them. In the past, we got around that
very easily by relying on bdrv_close_all() bypassing bdrv_delete(), and
bdrv_close() simply ignoring that condition. We should fix that by
releasing all named dirty bitmaps in bdrv_close() (there should not be
any unnamed bitmaps left) and moving the assertion from bdrv_delete()
there.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
So far, live migration with shared storage meant that the image is in a
not-really-ready don't-touch-me state on the destination while the
source is still actively using it, but after completing the migration,
the image was fully opened on both sides. This is bad.
This patch adds a block driver callback to inactivate images on the
source before completing the migration. Inactivation means that it goes
to a state as if it was just live migrated to the qemu instance on the
source (i.e. BDRV_O_INACTIVE is set). You're then supposed to continue
either on the source or on the destination, which takes ownership of the
image.
A typical migration looks like this now with respect to disk images:
1. Destination qemu is started, the image is opened with
BDRV_O_INACTIVE. The image is fully opened on the source.
2. Migration is about to complete. The source flushes the image and
inactivates it. Now both sides have the image opened with
BDRV_O_INACTIVE and are expecting the other side to still modify it.
3. One side (the destination on success) continues and calls
bdrv_invalidate_all() in order to take ownership of the image again.
This removes BDRV_O_INACTIVE on the resuming side; the flag remains
set on the other side.
This ensures that the same image isn't written to by both instances
(unless both are resumed, but then you get what you deserve). This is
important because .bdrv_close for non-BDRV_O_INACTIVE images could write
to the image file, which is definitely forbidden while another host is
using the image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Instead of covering only the state of images on the migration
destination before the migration is completed, the flag will also cover
the state of images on the migration source after completion. This
common state implies that the image is technically still open, but no
writes will happen and any cached contents will be reloaded from disk if
and when the image leaves this state.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
We can only clear BDRV_O_INCOMING if the caches were actually
invalidated.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
bdrv_common_open() modified bs->open_flags after inferring the set of
options to pass to the driver's .bdrv_open callback. This means that the
cache options were correctly set in bs->open_flags (and therefore
correctly displayed in 'info block'), but the image would actually be
opened with the default cache mode instead.
This patch removes the flags parameter to bdrv_common_open() (except for
BDRV_O_NO_BACKING it's the same as bs->open_flags anyway, and having two
names for the same thing is confusing), and moves the assignment of
open_flags down to immediately before calling into the block drivers. In
all other places, bs->open_flags is now used consistently.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Done with this Coccinelle semantic patch
@@
expression FMT, E1, E2;
expression list ARGS;
@@
- error_setg(E1, FMT, ARGS, error_get_pretty(E2));
+ error_propagate(E1, E2);/*###*/
+ error_prepend(E1, FMT/*@@@*/, ARGS);
followed by manual cleanup, first because I can't figure out how to
make Coccinelle transform strings, and second to get rid of now
superfluous error_propagate().
We now use or propagate the original error whole instead of just its
message obtained with error_get_pretty(). This avoids suppressing its
hint (see commit 50b7b00), but I can't see how the errors touched in
this commit could come with hints. It also improves the message
printed with &error_abort when we screw up (see commit 1e9b65b).
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
bdrv_create() sets an error and returns -errno on failure. When the
latter is interesting, the error is created with error_setg_errno().
bdrv_append_temp_snapshot() uses the error's message to create a new
one with error_setg_errno(). This adds a strerror() that is either
uninteresting or duplicate. Use error_setg() instead.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-7-git-send-email-armbru@redhat.com>
bdrv_close is used when ejecting a medium. Use a drained section to ensure
that all I/O goes to either the old medium or the bitbucket.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1450867706-19860-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Add an opaque value which is to be passed to the bdrv_amend_options()
status callback.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds the cache mode options to the QDict, so that they can be
specified for child nodes (e.g. backing.cache.direct=off).
The cache modes are not removed from the flags at this point; instead,
options and flags are kept in sync. If the user specifies both flags and
options, the options take precedence.
Child node inherit cache modes as options now, they don't use flags any
more.
Note that this forbids specifying the cache mode for empty drives. It
didn't make sense anyway to specify it there, because it didn't have any
effect. blockdev_init() considers the cache options now bdrv_open()
options and therefore doesn't create an empty drive any more but calls
into bdrv_open(). This in turn will fail with no driver and filename
specified.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This patch adds a QemuOpts for generic block layer options to
bdrv_reopen_prepare(). The only two options that currently exist
(node-name and driver) cannot be changed, so the only thing we do is
putting them right back into the QDict so that we check at the end that
they are indeed unchanged.
We will add new options soon that can actually be changed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
bs->options doesn't only contain options that the user explicitly
requested, but also option that were derived from flags, the filename or
inherited from the parent node.
For reopen, it is important to know the difference because reopening the
parent can change inherited values in child nodes, but it shouldn't
change any options that were explicitly specified for the child.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The next patch distinguishes options that were explicitly set and
options that were derived. bdrv_fill_option() added options of both
types: Options given by json: syntax should be counted as explicit, but
the rest is derived.
In preparation for the distinction, move json: parse to a separate
function.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Options are not actually inherited from the parent node yet, but this
commit lays the grounds for doing so.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The interesting part of reopening an image is from which sources the
effective options should be taken, i.e. which options take precedence
over which other options. This patch documents the precedence that will
be implemented in the following patches.
It also refactors bdrv_reopen_queue(), so that the top-level reopened
node is handled the same way as children are. Option/flag inheritance
from the parent becomes just one item in the list and is done at the
beginning of the function, similar to how the other items are/will be
handled.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
If the child was defined in the same context (-drive argument or
blockdev-add QMP command) as its parent, a reopen of the parent should
work the same and allow changing options of the child.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Instead of passing a separate drv argument to bdrv_open_common(), just
make sure that a "driver" option is set in the QDict. This also means
that a "driver" entry is consistently present in bs->options now.
This is another step towards keeping all options in the QDict (which is
the represenation of the blockdev-add QMP command).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
In order to decide whether a blkdebug: filename can be produced or a
json: one is necessary, blkdebug checked whether bs->options had more
options than just "config", "x-image" or "image" (the latter including
nested options). That doesn't work well when generic block layer options
are present.
This patch passes an option QDict to the driver that contains only
driver-specific options, i.e. the options for the general block layer as
well as child nodes are already filtered out. Works much better this
way.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Some drivers have nested options (e.g. blkdebug rule arrays), which
don't belong to a child node and shouldn't be removed. Don't remove all
options with "." in their name, but check for the complete prefixes of
actually existing child nodes.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The code already special-cased "node-name", which is currently the only
option passed in the QDict that isn't driver-specific. Generalise the
code to take all general block layer options into consideration.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
For bs->file, using references to existing BDSes has been possible for a
while already. This patch enables the same for bs->backing.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This fixes bdrv_reopen() calls like the following one:
qemu-io -c 'open -o overlap-check.template=all /tmp/test.qcow2' \
-c 'reopen -o overlap-check=none'
The approach taken so far would result in an options QDict that has both
"overlap-check.template=all" and "overlap-check=none", which obviously
conflicts. In this case, the old option should be overridden by the
newly specified option.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
No need to keep two separate enums, where editing one is likely
to forget the other. Now that we can specify a qapi enum prefix,
we don't even have to change the bulk of the uses.
get_event_by_name() could perhaps be replaced by qapi_enum_parse(),
but I left that for another day.
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-20-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The "need_check_timer" is used to clear the "NEED_CHECK" flag in the
image header after a grace period once metadata update has finished. In
compliance to the bdrv_drain semantics we should make sure it remains
deleted once .bdrv_drain is called.
We cannot reuse qed_need_check_timer_cb because here it doesn't satisfy
the assertion. Do the "plug" and "flush" calls manually.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1447064214-29930-10-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
A few uses of error_set(ERROR_CLASS_GENERIC_ERROR) were missed in
c6bd8c706, or have snuck in since. Nuke them.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447224690-9743-19-git-send-email-eblake@redhat.com>
Acked-by: Andreas Färber <afaerber@suse.de>
[Indentation tidied up, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
There are two ways to check for I/O limits in a BlockDriverState:
- bs->throttle_state: if this pointer is not NULL, it means that this
BDS is member of a throttling group, its ThrottleTimers structure
has been initialized and its I/O limits are ready to be applied.
- bs->io_limits_enabled: if true it means that the throttle_state
pointer is valid _and_ the limits are currently enabled.
The latter is used in several places to check whether a BDS has I/O
limits configured, but what it really checks is whether requests
are being throttled or not. For example, io_limits_enabled can be
temporarily set to false in cases like bdrv_read_unthrottled() without
otherwise touching the throtting configuration of that BDS.
This patch replaces bs->io_limits_enabled with bs->throttle_state in
all cases where what we really want to check is the existence of I/O
limits, not whether they are currently enabled or not.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Passing an empty string allows opening an image but not its backing
file. This was already described in the API documentation, only the
implementation was missing.
This is useful for creating snapshots using images opened with
blockdev-add, since they are not supposed to have a backing image
before the operation.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When inserting a BDS tree into a BB, we will need to add the root BDS to
this list. Since we will want to do that in the blockdev-insert-medium
implementation in blockdev.c, we will need access to it there.
This patch is not exactly elegant, but bdrv_states will be removed in
the future anyway because we no longer need it since we have BBs.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
blk_bs() will not necessarily return a non-NULL value any more (unless
blk_is_available() is true or it can be assumed to otherwise, e.g.
because it is called immediately after a successful blk_new_with_bs() or
blk_new_open()).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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>
As the comment above bdrv_get_stats() says, BlockAcctStats is something
which belongs to the device instead of each BlockDriverState. This patch
therefore moves it into the BlockBackend.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
guest_block_size is a guest device property so it should be moved into
the interface between block layer and guest devices, which is the
BlockBackend.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In order to handle host device passthrough, some guest device models
may call blk_is_inserted() to check whether the medium is inserted on
the host, when checking the guest tray status.
This tray status is inquired by blk_dev_change_media_cb(); because
bdrv_is_inserted() (invoked by blk_is_inserted()) always returns false
for BDS with drv set to NULL, blk_dev_change_media_cb() should therefore
be called before drv is set to NULL.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If bdrv_is_inserted() is called on the top level BDS, it should make
sure all nodes in the BDS tree are actually inserted.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Make bdrv_is_inserted(), blk_is_inserted(), and the callback
BlockDriver.bdrv_is_inserted() return a bool.
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This flag should not be set for the root BDS only, but for any BDS that
is being created while incoming migration is pending, so setting it is
moved from blockdev_init() to bdrv_fill_options().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The coroutine files are currently referenced by the block-obj-y
variable. The coroutine functionality though is already used by
more than just the block code. eg migration code uses coroutine
yield. In the future the I/O channel code will also use the
coroutine yield functionality. Since the coroutine code is nicely
self-contained it can be easily built as part of the libqemuutil.a
library, making it widely available.
The headers are also moved into include/qemu, instead of the
include/block directory, since they are now part of the util
codebase, and the impl was never in the block/ directory
either.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
If a node-name is not specified, automatically generate the node-name.
Generated node-names will use the "block" sub-system identifier.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_unref() can be called with a NULL argument and doesn't do anything
then. Make bdrv_unref_child() consistent with it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
bdrv_swap() is unused now. Remove it and all functions that have
no other users than bdrv_swap(). In particular, this removes the
.bdrv_rebind callbacks from block drivers.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
This cleans up the mess we left behind in the mirror code after the
previous patch. Instead of using bdrv_swap(), just change pointers.
The interface change of the mirror job that callers must consider is
that after job completion, their local BDS pointers still point to the
same node now. qemu-img must change its code accordingly (which makes it
easier to understand); the other callers stays unchanged because after
completion they don't do anything with the BDS, but just with the job,
and the job is still owned by the source BDS.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Remember all parent nodes and just change the pointers there instead of
swapping the contents of the BlockDriverState.
Handling of snapshot=on must be moved further down in bdrv_open()
because *pbs (which is the bs pointer in the BlockBackend) must already
be set before bdrv_append() is called. Otherwise bdrv_append() changes
the BB's pointer to the temporary snapshot, but bdrv_open() overwrites
it with the read-only original image.
We also need to be careful to update callers as the interface changes
(becomes less insane): Previously, the meaning of the two parameters was
inverted when bdrv_append() returns. Now any BDS pointers keep pointing
to the same node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
After bdrv_swap(), some fields must be moved back to their original BDS
to compensate for the effects that a swap of the contents of the objects
has while keeping the old addresses. Other fields must be moved back
because they should logically be moved and must stay on top
When replacing bdrv_swap() with operations changing the pointers in the
parents, we only need the latter and must avoid swapping the former.
Split the function accordingly.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
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>
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>
It is unused now.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch removes the temporary duplication between bs->file and
bs->file_child by converting everything to BdrvChild.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Store the BdrvChild for bs->file. At this point, bs->file_child->bs just
duplicates the bs->file pointer. Later, it will completely replace it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Disabling I/O limits from a BDS also drains all pending throttled
requests, so it should be done at the beginning of bdrv_close() with
the rest of the bdrv_drain() calls before the BlockDriver is closed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
