Some block devices may not have a filename in their BDS; and for some,
there may not even be a normal filename at all. To work around this, add
a function which tries to construct a valid filename for the
BDS.filename field.
If a filename exists or a block driver is able to reconstruct a valid
filename (which is placed in BDS.exact_filename), this can directly be
used.
If no filename can be constructed, we can still construct an options
QDict which is then converted to a JSON object and prefixed with the
"json:" pseudo protocol prefix. The QDict is placed in
BDS.full_open_options.
For most block drivers, this process can be done automatically; those
that need special handling may define a .bdrv_refresh_filename() method
to fill BDS.exact_filename and BDS.full_open_options themselves.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function returns NULL instead of aborting when an allocation fails.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
A call to retrieve the image size converts between bytes and sectors
several times:
* BlockDriver method bdrv_getlength() returns bytes.
* refresh_total_sectors() converts to sectors, rounding up, and stores
in total_sectors.
* bdrv_getlength() converts total_sectors back to bytes (now rounded
up to a multiple of the sector size).
* Callers wanting sectors rather bytes convert it right back.
Example: bdrv_get_geometry().
bdrv_nb_sectors() provides a way to omit the last two conversions.
It's exactly bdrv_getlength() with the conversion to bytes omitted.
It's functionally like bdrv_get_geometry() without its odd error
handling.
Reimplement bdrv_getlength() and bdrv_get_geometry() on top of
bdrv_nb_sectors().
The next patches will convert some users of bdrv_getlength() to
bdrv_nb_sectors().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch introduces three APIs so that following
patches can support queuing I/O requests and submitting them
as a batch for improving I/O performance.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
On some image chains, QEMU may not always be able to resolve the
filenames properly, when updating the backing file of an image
after a block commit.
For instance, certain relative pathnames may fail, or drives may
have been specified originally by file descriptor (e.g. /dev/fd/???),
or a relative protocol pathname may have been used.
In these instances, QEMU may lack the information to be able to make
the correct choice, but the user or management layer most likely does
have that knowledge.
With this extension to the block-commit api, the user is able to change
the backing file of the overlay image as part of the block-commit
operation.
This allows the change to be 'safe', in the sense that if the attempt
to write the overlay image metadata fails, then the block-commit
operation returns failure, without disrupting the guest.
If the commit top is the active layer, then specifying the backing
file string will be treated as an error (there is no overlay image
to modify in that case).
If a backing file string is not specified in the command, the backing
file string to use is determined in the same manner as it was
previously.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is a small helper function, to determine if 'base' is in the
chain of BlockDriverState 'top'. It returns true if it is in the chain,
and false otherwise.
If either argument is NULL, it will also return false.
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When failure occurs, 'ret' need be set, or may return 0 to indicate
success. Previously, an error was set in errp, but 0 was returned
anyway. So let bdrv_append_temp_snapshot() return an error code and
use that for the bdrv_open() return value.
Also, error_propagate() need be called only one time within a function.
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
drive-mirror will bdrv_swap the new BDS named node-name with the one
pointed by replaces when the mirroring is finished.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In order to let event defines use existing types later, instead of
redefine new ones, some old type defines for spice and vnc are changed,
and BlockErrorAction is moved from block.h to qapi schema. Note that
BlockErrorAction is not merged with BlockdevOnError.
At this point, VncInfo is not made a child of VncBasicInfo, because
VncBasicInfo has mandatory fields where VncInfo makes them optional.
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Now that all backend drivers are using QemuOpts, remove all
QEMUOptionParameter related codes.
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Change block layer to support both QemuOpts and QEMUOptionParameter.
After this patch, it will change backend drivers one by one. At the end,
QEMUOptionParameter will be removed and only QemuOpts is kept.
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
block_int.h is for block layer and block drivers, other code shouldn't
include it. But similar to bdrv_set_aio_context, bdrv_get_aio_context
should also be accessible from outside of block layer.
Move it.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
virtio-blk data-plane now uses the QEMU block layer for I/O. We do not
need raw_get_aio_fd() anymore. It was a layering violation anyway, so
let's get rid of it.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Up until now all BlockDriverState instances have used the QEMU main loop
for fd handlers, timers, and BHs. This is not scalable on SMP guests
and hosts so we need to move to a model with multiple event loops on
different host CPUs.
bdrv_set_aio_context() assigns the AioContext event loop to use for a
particular BlockDriverState. It first detaches the entire
BlockDriverState graph from the current AioContext and then attaches to
the new AioContext.
This function will be used by virtio-blk data-plane to assign a
BlockDriverState to its IOThread AioContext. Make
bdrv_aio_set_context() public since data-plane should not include
block_int.h.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is the common but non-trivial steps to assign or change the
backing_hd of BDS.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This drops BlockDriverState.in_use with op_blockers:
- Call bdrv_op_block_all in place of bdrv_set_in_use(bs, 1).
- Call bdrv_op_unblock_all in place of bdrv_set_in_use(bs, 0).
- Check bdrv_op_is_blocked() in place of bdrv_in_use(bs).
The specific types are used, e.g. in place of starting block backup,
bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP, ...).
There is one exception in block_job_create, where
bdrv_op_blocker_is_empty() is used, because we don't know the operation
type here. This doesn't matter because in a few commits away we will drop
the check and move it to callers that _do_ know the type.
- Check bdrv_op_blocker_is_empty() in place of assert(!bs->in_use).
Note: there is only bdrv_op_block_all and bdrv_op_unblock_all callers at
this moment. So although the checks are specific to op types, this
changes can still be seen as identical logic with previously with
in_use. The difference is error message are improved because of blocker
error info.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
BlockDriverState.op_blockers is an array of lists with BLOCK_OP_TYPE_MAX
elements. Each list is a list of blockers of an operation type
(BlockOpType), that marks this BDS as currently blocked for a certain
type of operation with reason errors stored in the list. The rule of
usage is:
* BDS user who wants to take an operation should check if there's any
blocker of the type with bdrv_op_is_blocked().
* BDS user who wants to block certain types of operation, should call
bdrv_op_block (or bdrv_op_block_all to block all types of operations,
which is similar to the existing bdrv_set_in_use()).
* A blocker is only referenced by op_blockers, so the lifecycle is
managed by caller, and shouldn't be lost until unblock, so typically
a caller does these:
- Allocate a blocker with error_setg or similar, call bdrv_op_block()
to block some operations.
- Hold the blocker, do his job.
- Unblock operations that it blocked, with the same reason pointer
passed to bdrv_op_unblock().
- Release the blocker with error_free().
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds the enum of all the operations that can be taken on a block
device.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_is_allocated() shouldn't return true for sectors that are
unallocated, but after the end of a short backing file, even though
such sectors are (correctly) marked as containing zeros.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The immediately visible effect of this patch is that it fixes committing
a temporary snapshot to its backing file. Previously, it would fail with
a "permission denied" error because bdrv_inherited_flags() forced the
backing file to be read-only, ignoring the r/w reopen of bdrv_commit().
The bigger problem this revealed is that the original open flags must
actually only be applied to the temporary snapshot, and the original
image file must be treated as a backing file of the temporary snapshot
and get the right flags for that.
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If target block driver forces compression, qemu-img convert needs to
write by cluster size as well as "-c" option.
Particularly, this applies for converting to VMDK streamOptimized
format.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Instead of having unlink() calls in the generic block layer, where we
aren't even guarateed to have a file name, move them to those block
drivers that are actually used and that always have a filename. Gets us
rid of some #ifdefs as well.
The patch also converts bs->is_temporary to a new BDRV_O_TEMPORARY open
flag so that it is inherited in the protocol layer and the raw-posix and
raw-win32 drivers can unlink the file.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
This patch adds an errp parameter to bdrv_new() and updates all its
callers. The next patches will make use of this in order to check for
duplicate IDs. Most of the callers know that their ID is fine, so they
can simply assert that there is no error.
Behaviour doesn't change with this patch yet as bdrv_new() doesn't
actually assign errors to errp.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
bdrv_getlength could fail, check the return value before using it.
Return NULL and set errno if it fails. Callers are updated to handle
the error case.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Since commit 9fd3171a, BDRV_O_SNAPSHOT uses an option QDict to specify
the originally requested image as the backing file of the newly created
temporary snapshot. This means that the filename is stored in
"file.filename", which is an option that is not parsed for protocol
names. Therefore things like -drive file=nbd:localhost:10809 were
broken because it looked for a local file with the literal name
'nbd:localhost:10809'.
This patch changes the way BDRV_O_SNAPSHOT works once again. We now open
the originally requested image as normal, and then do a similar
operation as for live snapshots to put the temporary snapshot on top.
This way, both driver specific options and parsed filenames work.
As a nice side effect, this results in code movement to factor
bdrv_append_temp_snapshot() out. This is a good preparation for moving
its call to drive_init() and friends eventually.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
If it returns an error, the migrated VM will not be started, but qemu
exits with an error message.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
This patch keep the recursive way of doing things but simplify it by giving
two responsabilities to all block filters implementors.
They will need to do two things:
-Set the is_filter field of their block driver to true.
-Implement the bdrv_recurse_is_first_non_filter method of their block driver like
it is done on the Quorum block driver. (block/quorum.c)
[Paolo Bonzini <pbonzini@redhat.com> pointed out that this patch changes
the semantics of blkverify, which now recurses down both bs->file and
s->test_file.
-- Stefan]
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This option is now unnecessary since specifying BDRV_O_PROTOCOL as flag
will do exactly the same.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add the bdrv_open() option BDRV_O_PROTOCOL which results in passing the
call to bdrv_file_open(). Additionally, make bdrv_file_open() static and
therefore bdrv_open() the only way to call it.
Consequently, all existing calls to bdrv_file_open() have to be adjusted
to use bdrv_open() with the BDRV_O_PROTOCOL flag instead.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Allow bdrv_open() to handle references to existing block devices just as
bdrv_file_open() is already capable of.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Make bdrv_open() take a pointer to a BDS pointer, similarly to
bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open()
will create a new BDS with an empty name; if the BDS pointer is not
NULL, that existing BDS will be reused (in the same way as bdrv_open()
already did).
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 implementing the alignment adjustment here, use the now
existing functionality of bdrv_co_do_pwritev().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
The alignment field is now set to the value that is promised to the
guest, rather than required by the host. The next patches will make
QEMU aware of the host-provided values, so make this clear.
The alignment is also not about memory buffers, but about the sectors on
the disk, change the documentation of the field.
At this point, the field is set by the device emulation, but completely
ignored by the block layer.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
bs->buffer_alignment is set by the device emulation and contains the
logical block size of the guest device. This isn't something that the
block layer should know, and even less something to use for determining
the right alignment of buffers to be used for the host.
The new BlockLimits field opt_mem_alignment tells the qemu block layer
the optimal alignment to be used so that no bounce buffer must be used
in the driver.
This patch may change the buffer alignment from 4k to 512 for all
callers that used qemu_blockalign() with the top-level image format
BlockDriverState. The value was never propagated to other levels in the
tree, so in particular raw-posix never required anything else than 512.
While on disks with 4k sectors direct I/O requires a 4k alignment,
memory may still be okay when aligned to 512 byte boundaries. This is
what must have happened in practice, because otherwise this would
already have failed earlier. Therefore I don't expect regressions even
with this intermediate state. Later, raw-posix can implement the hook
and expose a different memory alignment requirement.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
When reopening with different flags, or when backing files disappear
from the chain, the limits may change. Make sure they get updated in
these cases.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit@irqsave.net>
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Fam Zheng <famz@redhat.com>
There was two candidate ways to implement named node manipulation:
1)
{ 'command': 'block_passwd', 'data': {'*device': 'str',
'*node-name': 'str', 'password': 'str'}
}
2)
{ 'command': 'block_passwd', 'data': {'device': 'str',
'*device-is-node': 'bool',
'password': 'str'} }
Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to
rewrite the QMP block interface for 2.0.
Luiz does not like in 1 the fact that 2 fields are optional but one of them must
be specified leading to an abuse of the QMP semantic.
Kevin argumented that 2 what a clear abuse of the device field and would not be
practical when reading fast some log file because the user would read "device"
and think that a device is manipulated when it's in fact a node name.
Documentation of 1 make it pretty clear what to do for the user.
Kevin argued that all bs are node including devices ones so 2 does not make
sense.
Kevin also argued that rewriting the QMP block interface would not make disapear
the current one.
Kevin pushed the argument that making the QAPI generator compatible with the
semantic of the operation would need a rewrite that no one has done yet.
A vote has been done on the list to elect the version to use and 1 won.
For reference the complete thread is:
"[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block driver
states."
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add the minimum of code to prepare for the following patches.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add a common function for opening images to be used for block drivers
specified through BlockdevRefs in an option QDict. The difference from
bdrv_file_open() is that this function may invoke bdrv_open() instead,
allowing auto-detection of the driver to be used; and second, it
automatically extracts the BlockdevRef from the option QDict.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Allow specifying a reference to an existing block device (by name) for
bdrv_file_open() instead of a filename and/or options.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This will be used by the SCSI layer.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This lets bdrv_co_do_rw receive flags, so that it can be used for
zero writes.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds "remove_break" command which is the reverse of blkdebug
command "break": it removes all breakpoints with given tag and resumes
all the requests.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
We have multiple dirty bitmaps in BDS now, switch QAPI to allow query
it (BlockInfo.dirty_bitmaps), and also drop old BlockInfo.dirty.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Previously a BlockDriverState has only one dirty bitmap, so only one
caller (e.g. a block job) can keep track of writing. This changes the
dirty bitmap to a list and creates a BdrvDirtyBitmap for each caller, the
lifecycle is managed with these new functions:
bdrv_create_dirty_bitmap
bdrv_release_dirty_bitmap
Where BdrvDirtyBitmap is a linked list wrapper structure of HBitmap.
In place of bdrv_set_dirty_tracking, a BdrvDirtyBitmap pointer argument
is added to these functions, since each caller has its own dirty bitmap:
bdrv_get_dirty
bdrv_dirty_iter_init
bdrv_get_dirty_count
bdrv_set_dirty and bdrv_reset_dirty prototypes are unchanged but will
internally walk the list of all dirty bitmaps and set them one by one.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
this patch adds a call to completely zero out a block device.
the operation is sped up by checking the block status and
only writing zeroes to the device if they currently do not
return zeroes. optionally the zero writing can be sped up
by setting the flag BDRV_REQ_MAY_UNMAP to emulate the zero
write by unmapping if the driver supports it.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds 2 wrappers to read the unallocated_blocks_are_zero and
can_write_zeroes_with_unmap info from the BDI. The wrappers are
required to check for the existence of a backing_hd and
if the devices are opened with the correct flags.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
