In case a list of resources is provided to allocate_bars(), it directly
means we're restoring some existing BARs. That's why we shouldn't share
the codepath that creates BARs from scratch as we don't need to interact
with the device to retrieve the information.
Whenever resources are provided, we simply iterate over the list of
possible BAR indexes and create the BARs if the resource could be found.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Instead of defining some very generic resources as PioAddressRange or
MmioAddressRange for each PCI BAR, let's move to the new Resource type
PciBar in order to make things clearer. This allows the code for being
more readable, but also removes the need for hard assumptions about the
MMIO and PIO ranges. PioAddressRange and MmioAddressRange types can be
used to describe everything except PCI BARs. BARs are very special as
they can be relocated and have special information we want to carry
along with them.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to make the code more consistent and easier to read, we remove
the former tuple that was used to describe a BAR, replacing it with the
existing structure PciBarConfiguration.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The code was quite unclear regarding the type of index that was being
used regarding a BAR. This is improved by differenciating register
indexes and BAR indexes more clearly.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
By adding a new method id() to the PciDevice trait, we allow the caller
to retrieve a unique identifier. This is used in the context of BAR
relocation to identify the device being relocated, so that we can update
the DeviceTree resources for all PCI devices (and not only
VirtioPciDevice).
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Relying on the list of resources, VfioCommon is now able to allocate the
BARs at specific addresses. This will be useful for restoring VFIO and
vfio-user devices.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Updating the way of restoring BAR addresses for virtio-pci by providing
a more generic approach that will be reused for other PciDevice
implementations (i.e VfioPcidevice and VfioUserPciDevice).
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The calls to these functions are always preceded by a call to
InterruptSourceGroup::update(). By adding a masked boolean to that
function call it possible to remove 50% of the calls to the
KVM_SET_GSI_ROUTING ioctl as the the update will correctly handle the
masked or unmasked case.
This causes the ioctl to disappear from the perf report for a boot of
the VM.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Rust 2021 edition has a few improvements over the 2018 edition. Migrate
the project to 2021 edition by following recommended migration steps.
Luckily, the code itself doesn't require fixing.
Bump MSRV to 1.56 as it is required by the 2021 edition. Also fix the
clap build dependency to make Cloud Hypervisor build again.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Whenever a vfio-user device is dropped, the communication between the
VMM and the backend should be shutdown.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The same way we mask the writes coming from the guest to the message
control register related to MSI-X capability, let's do the same for MSI.
The point is to prevent the guest from writing to read-only bits.
The correct writable bits for MSI are only bits 0, 4, 5 and 6 of 2nd
16-bit word.
Those are:
* MSI Enable: 0
* Multiple Message Enable: 6-4
See "Table 7-39 Message Control Register for MSI" from
"NCB-PCI_Express_Base_5.0r1.0-2019-05-22.pdf".
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
I incorrectly used the MSI message control register values for the mask
not the the MSI-X control registers.
The correct writable fields for MSI-X are only bits 14 and 15 of 2nd
16-bit word.
Those are:
* Function Mask: 14
* MSI-X Enable: 15
See "Table 7-47 Message Control Register for MSI-X" from
"NCB-PCI_Express_Base_5.0r1.0-2019-05-22.pdf"
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
The PCI spec specifies that only the following bits are writable:
16: MSI Enable
20,21,22: Multiple Message Enable
26: Extended Message Data Enable
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By having the DeviceNode storing a PciBdf, we simplify the internal code
as well as allow for custom Serialize/Deserialize implementation for the
PciBdf structure. These custom implementations let us display the PCI
s/b/d/f in a human readable format.
Fixes#3711
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Make sure Cloud Hypervisor relies on upstream and actively maintained
vfio-ioctls crate from the rust-vmm/vfio repository instead of the
deprecated version coming from rust-vmm/vfio-ioctls repository.
Fixes#3673
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
AArch64 does not use IOBAR, and current code of panics the whole VMM if
we need to allocate the IOBAR.
This commit checks if IOBAR is enabled before the arch conditional code
of IOBAR allocation and if the IOBAR is not enabled, we can just skip
the IOBAR allocation and do nothing.
Fixes: https://github.com/cloud-hypervisor/cloud-hypervisor/issues/3479
Signed-off-by: Henry Wang <Henry.Wang@arm.com>
The sendmsg() syscall is limited in the number of fds it can handle.
This number matches that used by the vfio-user library and is
conservative (since we've seen it work with 64 fds.)
Fixes: #3401
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Because anyhow version 1.0.46 has been yanked, let's move back to the
previous version 1.0.45.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that vfio-ioctls correctly exposes the list of capabilities related
to each region, Cloud Hypervisor can decide to mmap a region based on
the presence or absence of MSIX_MAPPABLE. Instead of blindly mmap'ing
the region, we check if the MSI-X table or PBA is present on the BAR,
and if that's the case, we look for MSIX_MAPPABLE.
If MSIX_MAPPABLE is present, we can go ahead and mmap the entire region.
If MSIX_MAPPABLE is not present, we simply ignore the mmap'ing of this
region as it wouldn't be supported.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In particular use the accessor for getting the device id from the bdf.
As a side effect the VIOT table is now segment aware.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This will allow making the code that handles bdf parsing simpler and
remove the need for manual shifting.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Since each segment must have a non-overlapping memory range associated
with it the device memory must be equally divided amongst all segments.
A new allocator is used for each segment to ensure that BARs are
allocated from the correct address ranges. This requires changes to
PciDevice::allocate/free_bars to take that allocator and when
reallocating BARs the correct allocator must be identified from the
ranges.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In order to get proper performance out of hardware that might be passed
through the VM with VFIO, we decide to try mapping any region marked as
mappable, ignoring the failure and moving on to the next region. When
the mapping succeeds, we establish a list of user memory regions so that
we enable only subparts of the global mapping through the hypervisor.
This allows MSI-X table and PBA to keep trapping accesses from the guest
so that the VMM can properly emulate MSI-X.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This was causing some issues because of the use of 2 different versions
for the vm-memmory crate. We'll wait for all dependencies to be properly
resolved before we move to 0.7.0.
This reverts commit 76b6c62d07.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Move the PCI related state from the DeviceManager struct to a PciSegment
struct inside the DeviceManager. This is in preparation for multiple
segment support. Currently this state is just the bus itself, the MMIO
and PIO config devices and hotplug related state.
The main change that this required is using the Arc<Mutex<PciBus>> in
the device addition logic in order to ensure that
the bus could be created earlier.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Implement the infrastructure that lets a virtio-mem device map the guest
memory into the device. This is necessary since with virtio-mem zones
memory can be added or removed and the vfio-user device must be
informed.
Fixes: #3025
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By moving this from the VfioUserPciDevice to DeviceManager the client
can be reused for handling DMA mapping behind an IOMMU.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Looking up devices on the port I/O bus is time consuming during the
boot at there is an O(lg n) tree lookup and the overhead from taking a
lock on the bus contents.
Avoid this by adding a fast path uses the hardcoded port address and
size and directs PCI config requests directly to the device.
Command line:
target/release/cloud-hypervisor --kernel ~/src/linux/vmlinux --cmdline "root=/dev/vda1 console=ttyS0" --serial tty --console off --disk path=~/workloads/focal-server-cloudimg-amd64-custom-20210609-0.raw --api-socket /tmp/api
PIO exit: 17913
PCI fast path: 17871
Percentage on fast path: 99.8%
perf before:
marvin:~/src/cloud-hypervisor (main *)$ perf report -g | grep resolve
6.20% 6.20% vcpu0 cloud-hypervisor [.] vm_device:🚌:Bus::resolve
perf after:
marvin:~/src/cloud-hypervisor (2021-09-17-ioapic-fast-path *)$ perf report -g | grep resolve
0.08% 0.08% vcpu0 cloud-hypervisor [.] vm_device:🚌:Bus::resolve
The compromise required to implement this fast path is bringing the
creation of the PciConfigIo device into the DeviceManager::new() so that
it can be used in the VmmOps struct which is created before
DeviceManager::create_devices() is called.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This message only occurs sporadically and so it should be included at
info!() level. Enhance the output to also include the BAR number.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
The rust-vmm crates we're pulling from git have renamed their main
branches. We need to update the branch names we're giving to Cargo,
or people who don't have these dependencies cached will get errors
like this when trying to build:
error: failed to get `vm-fdt` as a dependency of package `arch v0.1.0 (/home/src/cloud-hypervisor/arch)`
Caused by:
failed to load source for dependency `vm-fdt`
Caused by:
Unable to update https://github.com/rust-vmm/vm-fdt?branch=master#031572a6
Caused by:
object not found - no match for id (031572a6edc2f566a7278f1e17088fc5308d27ab); class=Odb (9); code=NotFound (-3)
Signed-off-by: Alyssa Ross <hi@alyssa.is>
This resolves an issue with hotplug -> removal -> hotplug of a vfio-user
device as the allocator was not updated with the now unused entries.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
When mapping the region into the guest ensure that all the fields are
updated correctly as the unmap code path checks that they are set.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Taking advantage of the refactored VFIO code implement a new
VfioUserPciDevice that wraps the client for vfio-user and exposes the
BusDevice and PciDevice into the VMM.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This doesn't really affect the build as we ship a Cargo.lock with fixed
versions in. However for clarity it makes sense to use fixed versions
throughout and let dependabot update them.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
After the refactoring to split the common VFIO code out for vfio-user
there were some inconsistencies in the error handling. Correct this so
that the error is independent of the transport (hardware vs user) VFIO
and migrate to anyhow/thiserror in the process. Some unused errors from
earlier refactoring have also been removed.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Returning a reference is not possible for the vfio-user code as it is
constructed for the function.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Rename the wrapper trait and structs since this will be used for more
than reading the PCI config.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This allows the code to be used from a different module in the same
crate for vfio-user support.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Split data that will need to be common between VfioPciDevice and
VfioUserPciDevice into a common struct. Currently this has no methods
but they will be added soon.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By splitting this into a trait with common code extracted then this
will allow extensive reuse of logic in the vfio-user version.
This commit also changed the order of parameters on
::write_config_dword() to place offset first to match the other
functions.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
With the new beta version, clippy complains about redundant allocation
when using Arc<Box<dyn T>>, and suggests replacing it simply with
Arc<dyn T>.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The BAR calculation code was incorrect for calculating I/O BARs but also
has misleading comments (mixing bits and bytes, first and least
significant, etc).
This change adjusts the algorithm to more closely match the version
described in the PCI specification and takes advantage of Rust's binary
literals for ease of reading. Although this is slightly longer by
calculating the 64-bit and 32-bit paths separately I think this is
easier to read.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Previously the same function was used to both create and remove regions.
This worked on KVM because it uses size 0 to indicate removal.
MSHV has two calls -- one for creation and one for removal. It also
requires having the size field available because it is not slot based.
Split set_user_memory_region to {create/remove}_user_memory_region. For
KVM they still use set_user_memory_region underneath, but for MSHV they
map to different functions.
This fixes user memory region removal on MSHV.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Now all crates use edition = "2018" then the majority of the "extern
crate" statements can be removed. Only those for importing macros need
to remain.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
The logic wasn't quite right, as it wasn't detecting BAR reprogramming
when the upper part of the address was identical. For instance, a BAR
moved from 0x7fc0000000 to 0x7fd0000000 wasn't detected properly.
The logic has been updated and cleaned up to fix this issue, which was
observed when running Windows guests. This fixes the network hotplug
support as well.
Fixes#1797Fixes#1798
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Simplify snapshot & restore code by using generics to specify helper
functions that take / make a Serialize / Deserialize struct
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
warning: name `IORegion` contains a capitalized acronym
--> pci/src/configuration.rs:320:5
|
320 | IORegion = 0x01,
| ^^^^^^^^ help: consider making the acronym lowercase, except the initial letter (notice the capitalization): `IoRegion`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#upper_case_acronyms
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Now that virtio-mem devices can update VFIO mappings through dedicated
handlers, let's provide them from the DeviceManager.
Important to note these handlers should either be provided to virtio-mem
devices or to the unique virtio-iommu device. This must be mutually
exclusive.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Instead of letting the VfioPciDevice take the decision on how/when to
perform the DMA mapping/unmapping, we move this to the DeviceManager
instead.
The point is to let the DeviceManager choose which guest memory regions
should be mapped or not. In particular, we don't want the virtio-mem
region to be mapped/unmapped as it will be virtio-mem device
responsibility to do so.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit moves both pci and vmm code from the internal vfio-ioctls
crate to the upstream one from the rust-vmm project.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In case the VFIO device does not support MSI or MSI-X, the capabilities
should not be parsed, avoiding the exposure of unsupported capabilities.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Make sure to propagate the error coming from VfioDevice when trying to
enable INTx, MSI or MSI-X interrutps.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
With all the preliminary work done in the previous commits, we can
update the VFIO implementation to support INTx along with MSI and MSI-X.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In anticipation for supporting the notifier function for the legacy
interrupt source group, we need this function to return an EventFd
instead of a reference to this same EventFd.
The reason is we can't return a reference when there's an Arc<Mutex<>>
involved in the call chain.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
We need to be able to return the barrier from the code that prepares to
activate the virtio device. This triggered by a write to the
configuration fields stored in the PCI BAR. Since bars can be accessed
by both memory mapping and through PCI config I/O several prototypes
must be changed.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This can be uses to indicate to the caller that it should wait on the
barrier before returning as there is some asynchronous activity
triggered by the write which requires the KVM exit to block until it's
completed.
This is useful for having vCPU thread wait for the VMM thread to proceed
to activate the virtio devices.
See #1863
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This is a new clippy check introduced in 1.47 which requires the use of
the matches!() macro for simple match blocks that return a boolean.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
A new version of vm-memory was released upstream which resulted in some
components pulling in that new version. Update the version number used
to point to the latest version but continue to use our patched version
due to the fix for #1258
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By looking at Linux kernel boot time, we identified that a lot of time
was spent registering and unregistering IRQ fds to KVM. This is not
efficient and certainly not a wrong behavior from the Linux kernel,
but rather a problem with the Cloud-Hypervisor's implementation of
MSI-X.
The way to fix this issue is by ensuring the initial conditions are
correct, which means the entire MSI-X vector table must be disabled
and masked. Additionally, each vector must be individually masked.
With these correct conditions, Linux won't start masking interrupt
vectors, and later unmask them since they will be seen as masked from
the beginning. This means the OS will simply have to unmask them when
needed, avoiding the extra operation.
Another aspect of this patch is to prevent Cloud-Hypervisor from
enabling (by registering IRQ fd) all vectors when either the global
'mask' or 'enable' bits are set. Instead, we can simply let the mask()
and unmask() operations take care of it if needed.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Misspellings were identified by https://github.com/marketplace/actions/check-spelling
* Initial corrections suggested by Google Sheets
* Additional corrections by Google Chrome auto-suggest
* Some manual corrections
Signed-off-by: Josh Soref <jsoref@users.noreply.github.com>
This removes the dependency of the pci crate on the devices crate which
now only contains the device implementations themselves.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
There will be some cases where the implementation of the snapshot()
function from the Snapshottable trait will require to modify some
internal data, therefore we make this possible by updating the trait
definition with snapshot(&mut self).
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This fixes `cargo vendor` throwing an error
```
$ cargo vendor
error: failed to sync
Caused by:
found duplicate version of package `vfio-bindings v0.2.0` vendored from two sources:
source 1: https://github.com/rust-vmm/vfio-bindings#f08cbcbf
source 2: registry `https://github.com/rust-lang/crates.io-index`
```
Both sources are indeed same, the conflict is only cause by the
different URLs.
Signed-off-by: Anatol Belski <ab@php.net>
This simplies some of the handling for PCI BARs particularly with
respect to snapshot and restore. No attempt has been made to handle the
64-bit bar handling in a different manner to that which was used before.
Fixes: #1153
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In this commit we saved the BDF of a PCI device and set it to "devid"
in GSI routing entry, because this field is mandatory for GICv3-ITS.
Signed-off-by: Michael Zhao <michael.zhao@arm.com>
The type is now hypervisor::Vm. Switch from KVM specific name vm_fd to a
generic name just like 8186a8eee6 ("vmm: interrupt: Rename vm_fd").
No functional change.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Start moving the vmm, arch and pci crates to being hypervisor agnostic
by using the hypervisor trait and abstractions. This is not a complete
switch and there are still some remaining KVM dependencies.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Currently, not every feature of the cloud-hypervisor is enabled
on AArch64, which means that on AArch64 machines, the
`run_unit_tests.sh` needs to be tailored and some unit test cases
should be run on x86_64 only.
Also this commit fixes the typo and unifies `Arm64` and `AArch64`
in the AArch64 document.
Signed-off-by: Henry Wang <Henry.Wang@arm.com>
cloud-hypervisor: 763.978581807s: ERROR:pci/src/vfio.rs:651 -- failed to remove all guest memory regions from iommu table
when poweroff a vm with vfio device, clh will finally remove all guest memory region from iommu table
with the method unset_dma_map, not method setup_dma_map.
Signed-off-by: LiYa'nan <oliverliyn@gmail.com>
There is a much stronger PCI dependency from vfio_pci.rs than a VFIO one
from pci/src/vfio.rs. It seems more natural to have the PCI specific
VFIO implementation in the PCI crate rather than the other way around.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to let the PciBus user choose where a device should be placed
on the bus, a new function get_device_id() is introduced. This will be
helpful in the context of snapshot/restore as the caller will be able to
place the PCI devices on the same slot they were placed before the
snapshot was taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The PCI configuration from each PCI device is modified at runtime as we
can expect the guest OS to write to some PCI capability structure, or
move the BAR to a different location in the guest address space.
For all the reasons why such configuration might differ from the initial
configuration, we must store the registers values to be able to restore
them with the right values whenever a PCI device is being restored.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to restore devices relying on MSI-X, the MsixConfig structure
must be restored with the correct values. Additionally, the KVM routes
must be restored so that interrupts can be delivered through KVM the way
they were configured before the snapshot was taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
When reporting the BAR size it is necessary to return a value that is
encoded such that all the bits are set that represent the mask of the
natural alignment of the field.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Add support for specifying the PCI revision in the PCI configuration and
populate this with the value of 1 for virtio-pci devices.
The virtio-pci specification is slightly ambiguous only saying that
transitional (i.e. devices that support legacy and virtio 1.0) should
set this to 0. In practice it seems that software expects the revision
to be set to 1 for modern only devices.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By using a Vec to hold the list of devices on the PciBus, there's a
problem when we use unplug. Indeed, the vector of devices gets reduced
and if the unplugged device was not the last one from the list, every
other device after this one is shifted on the bus.
To solve this problem, a HashMap is used. This allows to keep track of
the exact place where each device stands on the bus.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The point of this new method is to let the caller decide when the
implementation of the PciDevice should free the BARs previously
allocated through the other method allocate_bars().
This provides a way to perform proper cleanup for any PCI device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Upon removal of a PCI device, make sure we don't hold onto the device ID
as it could be reused for another device later.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to handle the case where devices are very often plugged and
unplugged from a VM, we need to handle the PCI device ID allocation
better.
Any PCI device could be removed, which means we cannot simply rely on
the vector size to give the next available PCI device ID.
That's why this patch stores in memory the information about the 32
slots availability. Based on this information, whenever a new slot is
needed, the code can correctly provide an available ID, or simply return
an error because all slots are taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Simple function relying on the retain() method from std::Vec, allowing
to remove every occurence of the same device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that the BusDevice devices are stored as Weak references by the IO
and MMIO buses, there's no need to use Weak references from the PciBus
anymore.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
