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>
