Commit Graph

61436 Commits

Author SHA1 Message Date
Kevin Wolf
6a74c075ac job: Move job_finish_sync() to Job
block_job_finish_sync() doesn't contain anything block job specific any
more, so it can be moved to Job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
3453d97243 job: Move .complete callback to Job
This moves the .complete callback that tells a READY job to complete
from BlockJobDriver to JobDriver. The wrapper function job_complete()
doesn't require anything block job specific any more and can be moved
to Job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
b69f777dd9 job: Add job_drain()
block_job_drain() contains a blk_drain() call which cannot be moved to
Job, so add a new JobDriver callback JobDriver.drain which has a common
implementation for all BlockJobs. In addition to this we keep the
existing BlockJobDriver.drain callback that is called by the common
drain implementation for all block jobs.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
004e95df98 job: Convert block_job_cancel_async() to Job
block_job_cancel_async() did two things that were still block job
specific:

* Setting job->force. This field makes sense on the Job level, so we can
  just move it. While at it, rename it to job->force_cancel to make its
  purpose more obvious.

* Resetting the I/O status. This can't be moved because generic Jobs
  don't have an I/O status. What the function really implements is a
  user resume, except without entering the coroutine. Consequently, it
  makes sense to call the .user_resume driver callback here which
  already resets the I/O status.

  The old block_job_cancel_async() has two separate if statements that
  check job->iostatus != BLOCK_DEVICE_IO_STATUS_OK and job->user_paused.
  However, the former condition always implies the latter (as is
  asserted in block_job_iostatus_reset()), so changing the explicit call
  of block_job_iostatus_reset() on the former condition with the
  .user_resume callback on the latter condition is equivalent and
  doesn't need to access any BlockJob specific state.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
4ad351819b job: Move single job finalisation to Job
This moves the finalisation of a single job from BlockJob to Job.

Some part of this code depends on job transactions, and job transactions
call this code, we introduce some temporary calls from Job functions to
BlockJob ones. This will be fixed once transactions move to Job, too.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
139a9f020d job: Add job_event_*()
Go through the Job layer in order to send QMP events. For the moment,
these functions only call a notifier in the BlockJob layer that sends
the existing commands.

This uses notifiers rather than JobDriver callbacks because internal
users of jobs won't receive QMP events, but might still be interested
in getting notified for the events.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
5d4f376998 blockjob: Split block_job_event_pending()
block_job_event_pending() doesn't only send a QMP event, but it also
transitions to the PENDING state. Split the function so that we get one
part only sending the event (like other block_job_event_* functions) and
another part that does the state transition.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
bb02b65c7d job: Move BlockJobCreateFlags to Job
This renames the BlockJobCreateFlags constants, moves a few JOB_INTERNAL
checks to job_create() and the auto_{finalize,dismiss} fields from
BlockJob to Job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
dbe5e6c1f7 job: Replace BlockJob.completed with job_is_completed()
Since we introduced an explicit status to block job, BlockJob.completed
is redundant because it can be derived from the status. Remove the field
from BlockJob and add a function to derive it from the status at the Job
level.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
b15de82867 job: Move pause/resume functions to Job
While we already moved the state related to job pausing to Job, the
functions to do were still BlockJob only. This commit moves them over to
Job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
5d43e86e11 job: Add job_sleep_ns()
There is nothing block layer specific about block_job_sleep_ns(), so
move the function to Job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
da01ff7f38 job: Move coroutine and related code to Job
This commit moves some core functions for dealing with the job coroutine
from BlockJob to Job. This includes primarily entering the coroutine
(both for the first and reentering) and yielding explicitly and at pause
points.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
1908a5590c job: Move defer_to_main_loop to Job
Move the defer_to_main_loop functionality from BlockJob to Job.

The code can be simplified because we can use job->aio_context in
job_defer_to_main_loop_bh() now, instead of having to access the
BlockDriverState.

Probably taking the data->aio_context lock in addition was already
unnecessary in the old code because we didn't actually make use of
anything protected by the old AioContext except getting the new
AioContext, in case it changed between scheduling the BH and running it.
But it's certainly unnecessary now that the BDS isn't accessed at all
any more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:50 +02:00
Kevin Wolf
08be6fe26f job: Add Job.aio_context
When block jobs need an AioContext, they just take it from their main
block node. Generic jobs don't have a main block node, so we need to
assign them an AioContext explicitly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
daa7f2f946 job: Move cancelled to Job
We cannot yet move the whole logic around job cancelling to Job because
it depends on quite a few other things that are still only in BlockJob,
but we can move the cancelled field at least.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
80fa2c756b job: Add reference counting
This moves reference counting from BlockJob to Job.

In order to keep calling the BlockJob cleanup code when the job is
deleted via job_unref(), introduce a new JobDriver.free callback. Every
block job must use block_job_free() for this callback, this is asserted
in block_job_create().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
a50c2ab858 job: Move state transitions to Job
This moves BlockJob.status and the closely related functions
(block_)job_state_transition() and (block_)job_apply_verb to Job. The
two QAPI enums are renamed to JobStatus and JobVerb.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
e7c1d78bbd job: Maintain a list of all jobs
This moves the job list from BlockJob to Job. Now we can check for
duplicate IDs in job_create().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
fd61a701f1 job: Add job_delete()
This moves freeing the Job object and its fields from block_job_unref()
to job_delete().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
252291eaea job: Add JobDriver.job_type
This moves the job_type field from BlockJobDriver to JobDriver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
8e4c87000f job: Rename BlockJobType into JobType
QAPI types aren't externally visible, so we can rename them without
causing problems. Before we add a job type to Job, rename the enum
so it can be used for more than just block jobs.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
33e9e9bd62 job: Create Job, JobDriver and job_create()
This is the first step towards creating an infrastructure for generic
background jobs that aren't tied to a block device. For now, Job only
stores its ID and JobDriver, the rest stays in BlockJob.

The following patches will move over more parts of BlockJob to Job if
they are meaningful outside the context of a block job.

BlockJob.driver is now redundant, but this patch leaves it around to
avoid unnecessary churn. The next patches will get rid of almost all of
its uses anyway so that it can be removed later with much less churn.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
a81e0a825e blockjob: Improve BlockJobInfo.offset/len documentation
Clarify that len is just an estimation of the end value of offset, and
that offset increases monotonically while len can change arbitrarily.

While touching the documentation of offset, move it directly after len
to match the order of the declaration below.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
cd44d96be9 blockjob: Update block-job-pause/resume documentation
Commit 0ec4dfb8d changed block-job_pause/resume so that they return an
error if they don't do anything because the job is already
paused/running. It forgot to update the documentation, so do that now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2018-05-23 14:30:49 +02:00
Kevin Wolf
169926dccf qemu-iotests: Remove MIG_SOCKET from non-migration tests
185 and 191 define a MIG_SOCKET even though they don't do anything with
migration. Remove the useless variable.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2018-05-23 14:30:47 +02:00
Kevin Wolf
c4d1ff2bfc qemu-iotests: Add more tests to "migration" group
grep for "migrate" turns up a few test cases which use migration, but
haven't been in the "migration" group so far. Add them to the group.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2018-05-23 14:30:23 +02:00
Peter Maydell
ae8622ec19 sheepdog: Remove unnecessary NULL check in sd_prealloc()
In commit 8b9ad56e9c, we removed the code that could result
in our getting to sd_prealloc()'s out_with_err_set label with a
NULL blk pointer. That makes the NULL check in the error-handling
path unnecessary, and Coverity gripes about it (CID 1390636).
Delete the redundant check.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-23 13:29:06 +02:00
Kevin Wolf
4e24ed138b qemu-iotests: 086 doesn't work with NFS
The reference output file only works for file. 'qemu-img convert -p'
makes a lot more progress updates for NFS than for file, so disable the
test for NFS.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2018-05-23 13:29:06 +02:00
Kevin Wolf
8908b253c4 qemu-iotests: Filter NFS paths
NFS paths were only partially filtered in _filter_img_create, _img_info
and _filter_img_info, resulting in "nfs://127.0.0.1TEST_DIR/t.IMGFMT".
This adds another replacement to the sed calls that matches the test
directory not as a host path, but as an NFS URL (the prefix as used for
$TEST_IMG).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2018-05-23 13:29:03 +02:00
Kevin Wolf
655ae6bb91 qemu-iotests: Fix paths for NFS
Test cases were trying to use nfs:// URLs as local filenames, which made
every test fail for NFS. With TEST_IMG and TEST_IMG_FILE set like for
the other protocols, NFS tests can pass again.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2018-05-23 12:20:34 +02:00
Tiwei Bie
703878e2e0 vhost-user: add Net prefix to internal state structure
We are going to introduce a shared vhost user state which
will be named as 'VhostUserState'. So add 'Net' prefix to
the existing internal state structure in the vhost-user
netdev to avoid conflict.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
85e99cf80b linux-headers: add kvm header for mips
kvm header for MIPS was manually excluded from auto-updates.

Update it now to 4.17-rc2.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
4337003647 linux-headers: add unistd.h on all arches
This adds unistd.h on ARM64 and MIPS and their dependencies.

Updated to Linux 4.17-rc2.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
9882d3ef3c update-linux-headers.sh: unistd.h, kvm consistency
Rework the update script slightly, add the unistd.h header and its
dependencies on all architectures.

This also removes the IA64 and MIPS from a KVM blacklist:
Linux dropped IA64, and there was never a reason to
exclude MIPS from kvm specifically - it was
excluded due to dependency of its unistd.h on sgidefs.h,
which we also import.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
fe7f9b8e6e linux-headers: drop kvm_para.h
Unused now and can be removed.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
1814eab673 x86/cpu: use standard-headers/asm-x86.kvm_para.h
Switch to the header we imported from Linux,
this allows us to drop a hack in kvm_i386.h.
More code will be dropped in the next patch.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
d49bd359d1 include/standard-headers: add asm-x86/kvm_para.h
Import asm-x86/kvm_para.h from linux where it can
be easily used on Linux and non-Linux platforms.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Michael S. Tsirkin
ec7b10800c update-linux-headers.sh: drop kvm_para.h hacks
It turns out (as will be clear from follow-up patches)
we do not really need any kvm para macros host side
for now, except on x86, and there we need it
unconditionally whether we run on kvm or we don't.

Import the x86 asm/kvm_para.h into standard-headers,
follow-up patches remove a bunch of code using this.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Peter Xu
ffcbbe722f vhost: add trace for IOTLB miss
Add some trace points for IOTLB translation for vhost. After vhost-user
is setup, the only IO path that QEMU will participate should be the
IOMMU translation, so it'll be good we can track this with explicit
timestamps when needed to see how long time we take to do the
translation, and whether there's anything stuck inside.  It might be
useful for triaging vhost-user problems.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:41 +03:00
Jonathan Helman
b7b1264429 virtio-balloon: add hugetlb page allocation counts
qemu should read and report hugetlb page allocation
counts exported in the following kernel patch:

    commit 4c3ca37c4a4394978fd0f005625f6064ed2b9a64
    Author: Jonathan Helman <jonathan.helman@oracle.com>
    Date:   Mon Mar 19 11:00:35 2018 -0700

    virtio_balloon: export hugetlb page allocation counts

    Export the number of successful and failed hugetlb page
    allocations via the virtio balloon driver. These 2 counts
    come directly from the vm_events HTLB_BUDDY_PGALLOC and
    HTLB_BUDDY_PGALLOC_FAIL.

Signed-off-by: Jonathan Helman <jonathan.helman@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2018-05-23 03:14:40 +03:00
Gerd Hoffmann
50a6fa8f93 allocate pci id for mdpy
mdpy is a sample pci device for vfio-mdev.  Not (yet) merged upstream,
patch available here:

https://www.kraxel.org/cgit/linux/commit/?h=vfio-sample-display&id=6fd86cff3d7df38ab89625b16fdd6434b1c18749

Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:40 +03:00
Zihan Yang
dda53ee93a hw/pci-host/q35: Replace hardcoded value with macro
During smram region initialization some addresses are hardcoded,
replace them with macro to be more clear to readers.

Previous patch forgets about one value and exceeds the line
limit of 90 characters. The v2 breaks a few long lines

Signed-off-by: Zihan Yang <whois.zihan.yang@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 03:14:40 +03:00
Paul Durrant
443c3c9cf1 xen_disk: be consistent with use of xendev and blkdev->xendev
Certain functions in xen_disk are called with a pointer to xendev
(struct XenDevice *). They then use container_of() to acces the surrounding
blkdev (struct XenBlkDev) but then in various places use &blkdev->xendev
when use of the original xendev pointer is shorter to express and clearly
equivalent.

This patch is a purely cosmetic patch which makes sure there is a xendev
pointer on stack for any function where the pointer is need on multiple
occasions modified those functions to use it consistently.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:22 -07:00
Paul Durrant
5ebf962652 xen_disk: use a single entry iovec
Since xen_disk now always copies data to and from a guest there is no need
to maintain a vector entry corresponding to every page of a request.
This means there is less per-request state to maintain so the ioreq
structure can shrink significantly.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:22 -07:00
Paul Durrant
a68bf540f6 xen_backend: make the xen_feature_grant_copy flag private
There is no longer any use of this flag outside of the xen_backend code.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:21 -07:00
Paul Durrant
06454c24ad xen_disk: remove use of grant map/unmap
Now that the (native or emulated) xen_be_copy_grant_refs() helper is
always available, the xen_disk code can be significantly simplified by
removing direct use of grant map and unmap operations.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:21 -07:00
Paul Durrant
3fe12b8403 xen_backend: add an emulation of grant copy
Not all Xen environments support the xengnttab_grant_copy() operation.
E.g. where the OS is FreeBSD or Xen is older than 4.8.0.

This patch introduces an emulation of that operation using
xengnttab_map_domain_grant_refs() and memcpy() for those environments.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:21 -07:00
Paul Durrant
58560f2ae7 xen: remove other open-coded use of libxengnttab
Now that helpers are available in xen_backend, use them throughout all
Xen PV backends.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:21 -07:00
Paul Durrant
5ee1d99913 xen_disk: remove open-coded use of libxengnttab
Now that helpers are present in xen_backend, this patch removes open-coded
calls to libxengnttab from the xen_disk code.

This patch also fixes one whitspace error in the assignment of the
XenDevOps initialise method.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:21 -07:00
Paul Durrant
9838824aff xen_backend: add grant table helpers
This patch adds grant table helper functions to the xen_backend code to
localize error reporting and use of xen_domid.

The patch also defers the call to xengnttab_open() until just before the
initialise method in XenDevOps is invoked. This method is responsible for
mapping the shared ring. No prior method requires access to the grant table.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2018-05-22 11:43:21 -07:00