Following the refactoring of the code allowing multiple threads to
access the same instance of the guest memory, this patch goes one step
further by adding RwLock to it. This anticipates the future need for
being able to modify the content of the guest memory at runtime.
The reasons for adding regions to an existing guest memory could be:
- Add virtio-pmem and virtio-fs regions after the guest memory was
created.
- Support future hotplug of devices, memory, or anything that would
require more memory at runtime.
Because most of the time, the lock will be taken as read only, using
RwLock instead of Mutex is the right approach.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The VMM guest memory was cloned (copied) everywhere the code needed to
have ownership of it. In order to clean the code, and in anticipation
for future support of modifying this guest memory instance at runtime,
it is important that every part of the code share the same instance.
Because VirtioDevice implementations need to have access to it from
different threads, that's why Arc must be used in this case.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Latest clippy version complains about our existing code for the
following reasons:
- trait objects without an explicit `dyn` are deprecated
- `...` range patterns are deprecated
- lint `clippy::const_static_lifetime` has been renamed to
`clippy::redundant_static_lifetimes`
- unnecessary `unsafe` block
- unneeded return statement
All these issues have been fixed through this patch, and rustfmt has
been run to cleanup potential formatting errors due to those changes.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The structure of the vmm-sys-util crate has changed with lots of code
moving to submodules.
This change adjusts the use of the imported structs to reference the
submodules.
Fixes: #145
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Update all dependencies with "cargo upgrade" with the exception of
vmm-sys-utils which needs some extra porting work.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
When reading from or writing to the MSI-X table, the function provided
by the PCI crate expects the offset to start from the beginning of the
table. That's why it is VFIO specific code to be responsible for
providing the right offset, which means it needs to be the offset
substracted by the beginning of the MSI-X table offset.
This bug was not discovered until we tested VFIO with some device where
the MSI-X table was placed on a BAR at an offset different from 0x0.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Relying on the newly added code in the pci crate, the vfio crate can now
properly expose an expansion ROM BAR if the device has one.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to support VFIO for devices supporting multiple functions,
we need to mask the multi-function bit (bit 7 from Header Type byte).
Otherwise, the guest kernel ends up tryng to enumerate those devices.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Since our VFIO code does not support pin based interrupt, but only MSI
and MSI-X, it is cleaner to not expose any Interrupt Pin to the guest by
setting its value to 0.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Until the codebase can properly expose the ROM BAR into the guest, it is
better to disable it for now, returning always 0 when the register is
being read.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The IO BAR alignment was already set to 4 bytes, this patch simply added
a comment for it.
The Memory BAR alignment was also set to the right value, but it was not
explained why 0x1000 was needed, and also why 0x10 could sometimes be
used as correct alignment.
A Memory BAR must be aligned at least on 16 bytes since the first 4 bits
are dedicated to some specific information about the BAR itself. But in
case a BAR is identified as mappable from VFIO, this means our VMM might
memory map it into the VMM address space, and set KVM accordingly using
the ioctl KVM_SET_USER_MEMORY_REGION. In case of KVM, we have to take
into account that it expects addresses to be page aligned, which means
4K in this case.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to correctly support multiple VFIO devices, we need to
increment the memory slot index every time it is being used to set some
user memory region through KVM. That's why the mem_slot parameter is
made mutable.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
KVM does not support multiple KVM VFIO devices to be created when
trying to support multiple VFIO devices. This commit creates one
global KVM VFIO device being shared with every VFIO device, which
makes possible the support for passing several devices through the
VM.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
VFIO explictly tells us if a MMIO region can be mapped into the guest
address space or not. Except for MSI-X table BARs, we try to map them
into the guest whenever VFIO allows us to do so. This avoids unnecessary
VM exits when the guest tries to access those regions.
Signed-off-by: Zhang, Xiong Y <xiong.y.zhang@intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
We track all MSI and MSI-X capabilities changes, which allows us to also
track all MSI and MSI-X table changes.
With both pieces of information we can build kvm irq routing tables and
map the physical device MSI/X vectors to the guest ones. Once that
mapping is in place we can toggle the VFIO IRQ API accordingly and
enable disable MSI or MSI-X interrupts, from the physical device up to
the guest.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to properly manage the VFIO device interrupt settings, we need
to keep track of both MSI and MSI-X PCI config capabilities changes.
When the guest programs the device for interrupt delivery, it writes to
the MSI and MSI-X capabilities. This information must be trapped and
cached in order to map the physical device interrupt delivery path to
the guest one. In other words, tracking MSI and MSI-X capabilites will
allow us to accurately build the KVM interrupt routes.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This brings the initial PCI support to the VFIO crate.
The VfioPciDevice is the main structure and holds an inner VfioDevice.
VfioPciDevice implements the PCI trait, leaving the IRQ assignments
empty as this will be driven by both the guest and the VFIO PCI device,
not by the VMM.
As we must trap BAR programming from the guest (We don't want to program
the actual device with guest addresses), we use our local PCI
configuration cache to read and write BARs.
Signed-off-by: Zhang, Xiong Y <xiong.y.zhang@intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
The Virtual Function I/O (VFIO) kernel subsystem exposes a vast and
relatively complex userspace API. This commit abstracts and simplifies
this API into both an internal and external API.
The external API is to be consumed by VFIO device implementation through
the VfioDevice structure. A VfioDevice instance can:
- Enable and disable all interrupts (INTX, MSI and MSI-X) on the
underlying VFIO device.
- Read and write all of the VFIO device memory regions.
- Set the system's IOMMU tables for the underlying device.
Signed-off-by: Zhang, Xiong Y <xiong.y.zhang@intel.com>
Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
