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>
