On Thu, 14 May 2020 16:38:17 +0100, Alexandru Elisei wrote:
> kvmtool uses the Linux-only dt property 'linux,pci-probe-only' to prevent
> it from trying to reassign the BARs. Let's make the BARs reassignable so we
> can get rid of this band-aid.
>
> During device configuration, Linux can assign a region resource to a BAR
> that temporarily overlaps with another device. This means that the code
> that emulates BAR reassignment must be aware of all the registered PCI
> devices. Because of this, and to avoid re-implementing the same code for
> each emulated device, the algorithm for activating/deactivating emulation
> as BAR addresses change lives completely inside the PCI code. Each device
> registers two callback functions which are called when device emulation is
> activated (for example, to activate emulation for a newly assigned BAR
> address), respectively, when device emulation is deactivated (a previous
> BAR address is changed, and emulation for that region must be deactivated).
>
> [...]
Applied to kvmtool (master), thanks!
[01/12] ioport: mmio: Use a mutex and reference counting for locking
https://git.kernel.org/will/kvmtool/c/09577ac58fef
[02/12] pci: Add helpers for BAR values and memory/IO space access
https://git.kernel.org/will/kvmtool/c/2f6384f924d7
[03/12] virtio/pci: Get emulated region address from BARs
https://git.kernel.org/will/kvmtool/c/e539f3e425fb
[04/12] vfio: Reserve ioports when configuring the BAR
https://git.kernel.org/will/kvmtool/c/a05e576f7fd8
[05/12] pci: Limit configuration transaction size to 32 bits
https://git.kernel.org/will/kvmtool/c/6ea32ebdb84b
[06/12] vfio/pci: Don't write configuration value twice
https://git.kernel.org/will/kvmtool/c/e1d0285c89ae
[07/12] Don't allow more than one framebuffers
https://git.kernel.org/will/kvmtool/c/cbf3d16fccba
[08/12] pci: Implement callbacks for toggling BAR emulation
https://git.kernel.org/will/kvmtool/c/5a8e4f25dd7b
[09/12] pci: Toggle BAR I/O and memory space emulation
https://git.kernel.org/will/kvmtool/c/46e04130d264
[10/12] pci: Implement reassignable BARs
https://git.kernel.org/will/kvmtool/c/465edc9d0fab
[11/12] arm/fdt: Remove 'linux,pci-probe-only' property
https://git.kernel.org/will/kvmtool/c/ad5e9056de0c
[12/12] vfio: Trap MMIO access to BAR addresses which aren't page aligned
https://git.kernel.org/will/kvmtool/c/b4fc4f605fc6
Cheers,
--
Will
https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev
