commit e35d46529cd99f29af7525ea7bc9b6b4e6fc5812
author Haiwei Li <haiwei.li@intel.corp-partner.google.com> Thu Feb 10 15:39:33 2022 +0800
committer Commit Bot <commit-bot@chromium.org> Mon Feb 28 21:55:09 2022 +0000
tree 12df70bb1a4d08b98041045ee243d16aa12d717e
parent a79e14bad553d370c846339bbc5b919257b59935

devices: vfio_pci: MMIO BAR allocation for devices on non-root buses

Since we'll be putting all PCI devices on non-root buses behind virtual
PCI-E root ports, MMIO BARs in such devices must be inside the forward
windows of their root ports. This presents additional requirements for
their MMIO BAR allocation:

1. All non-prefetchable BARs must be inside the same 32-bit MMIO window
2. All prefetchable BARs must be inside the same MMIO window, but
   different than the non-prefetchable MMIO window
3. Both windows must be 1MB-aligned
4. No other PCI devices should occupy MMIO space in these windows

Allocate the entire window from the system resource allocator to prevent
any space within the window from being used elsewhere. To maximize
memory space efficiency, use VfioResourceAllocator for BAR allocation.

BUG=b:185084350
TEST=passthrough a vfio-pci device with bus_number > 0 and static connet it
behind a pcie root port, then check pcie RP and vfio-pci device function in
guest.

Change-Id: Ic9865afc48eb3ff9fa475dbcfdf90642b012980c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3166888
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Commit-Queue: Daniel Verkamp <dverkamp@chromium.org>