| Message ID | 20210315153350.19988-1-andre.przywara@arm.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Unify I/O port and MMIO trap handling | expand |
Hi Will, Julien, On 3/15/21 3:33 PM, Andre Przywara wrote: > Hi, > > this version is addressing Alexandru's comments, fixing mostly minor > issues in the naming scheme. The biggest change is to keep the > ioport__read/ioport_write wrappers for the serial device. > For more details see the changelog below. > ============== > > At the moment we use two separate code paths to handle exits for > KVM_EXIT_IO (ioport.c) and KVM_EXIT_MMIO (mmio.c), even though they > are semantically very similar. Because the trap handler callback routine > is different, devices need to decide on one conduit or need to provide > different handler functions for both of them. > > This is not only unnecessary code duplication, but makes switching > devices from I/O port to MMIO a tedious task, even though there is no > real difference between the two, especially on ARM and PowerPC. > > For ARM we aim at providing a flexible memory layout, and also have > trouble with the UART and RTC device overlapping with the PCI I/O area, > so it seems indicated to tackle this once and for all. > > The first three patches do some cleanup, to simplify things later. > > Patch 04/22 lays the groundwork, by extending mmio.c to be able to also > register I/O port trap handlers, using the same callback prototype as > we use for MMIO. > > The next 14 patches then convert devices that use the I/O port > interface over to the new joint interface. This requires to rework > the trap handler routine to adhere to the same prototype as the existing > MMIO handlers. For most devices this is done in two steps: a first to > introduce the reworked handler routine, and a second to switch to the new > joint registration routine. For some devices the first step is trivial, > so it's done in one patch. > > Patch 19/22 then retires the old I/O port interface, by removing ioport.c > and friends. > Patch 20/22 uses the opportunity to clean up the memory map description, > also declares a new region (from 16MB on), where the final two patches > switch the UART and the RTC device to. They are now registered > on the MMIO "bus", when running on ARM or arm64. This moves them away > from the first 64KB, so they are not in the PCI I/O area anymore. I have reviewed the series and everything looks fine to me and ready to be merged. I have also ran the following tests: - On my x86_64 desktop, I ran a guest with --sdl, to exercise the vesa device. - On a rockpro64, I ran kvm-unit-tests for arm64 and arm (kvmtool was compiled for arm64); I also ran Linux guests using 4k and 64k pages with and without --force-pci. - On a Seattle machine, I did PCI passthrough for an Intel 82574L network card and ran Linux guests using 4k and 64k pages with and without --force-pci. - On an odroid-c4 (4 x Cortex-A55), I ran Linux guests using 4k, 16k and 64k pages with and without --force-pci. With this series merged, everything will be in place to bring back the patch that adds PCI Express 1.1 support for arm/arm64 [1]. The patch was previously dropped because the RTC and UART were overlapping with the PCI I/O space and EDK2 doesn't not understand PCI I/O bus addresses above 64k, but this series fixes that by moving the addresses of the two devices. [1] https://www.spinics.net/lists/kvm/msg211304.html Thanks, Alex
On Mon, 15 Mar 2021 15:33:28 +0000, Andre Przywara wrote: > this version is addressing Alexandru's comments, fixing mostly minor > issues in the naming scheme. The biggest change is to keep the > ioport__read/ioport_write wrappers for the serial device. > For more details see the changelog below. > ============== > > At the moment we use two separate code paths to handle exits for > KVM_EXIT_IO (ioport.c) and KVM_EXIT_MMIO (mmio.c), even though they > are semantically very similar. Because the trap handler callback routine > is different, devices need to decide on one conduit or need to provide > different handler functions for both of them. > > [...] Applied to kvmtool (master), thanks! [01/22] ioport: Remove ioport__setup_arch() https://git.kernel.org/will/kvmtool/c/97531eb2ca70 [02/22] hw/serial: Use device abstraction for FDT generator function https://git.kernel.org/will/kvmtool/c/a81be31eee6e [03/22] ioport: Retire .generate_fdt_node functionality https://git.kernel.org/will/kvmtool/c/9bc7e2ce343e [04/22] mmio: Extend handling to include ioport emulation https://git.kernel.org/will/kvmtool/c/96f0c86ce221 [05/22] hw/i8042: Clean up data types https://git.kernel.org/will/kvmtool/c/fc7696277b29 [06/22] hw/i8042: Refactor trap handler https://git.kernel.org/will/kvmtool/c/f7ef3dc0cd28 [07/22] hw/i8042: Switch to new trap handlers https://git.kernel.org/will/kvmtool/c/d24bedb1cc9a [08/22] x86/ioport: Refactor trap handlers https://git.kernel.org/will/kvmtool/c/82304999f936 [09/22] x86/ioport: Switch to new trap handlers https://git.kernel.org/will/kvmtool/c/3adbcb235020 [10/22] hw/rtc: Refactor trap handlers https://git.kernel.org/will/kvmtool/c/8c45f36430bd [11/22] hw/rtc: Switch to new trap handler https://git.kernel.org/will/kvmtool/c/123ee474b97b [12/22] hw/vesa: Switch trap handling to use MMIO handler https://git.kernel.org/will/kvmtool/c/38ae332ffcec [13/22] hw/serial: Refactor trap handler https://git.kernel.org/will/kvmtool/c/47a510600e08 [14/22] hw/serial: Switch to new trap handlers https://git.kernel.org/will/kvmtool/c/59866df60b4b [15/22] vfio: Refactor ioport trap handler https://git.kernel.org/will/kvmtool/c/a4a0dac75469 [16/22] vfio: Switch to new ioport trap handlers https://git.kernel.org/will/kvmtool/c/579bc61f8798 [17/22] virtio: Switch trap handling to use MMIO handler https://git.kernel.org/will/kvmtool/c/205eaa794be7 [18/22] pci: Switch trap handling to use MMIO handler https://git.kernel.org/will/kvmtool/c/1f56b9d10a28 [19/22] Remove ioport specific routines https://git.kernel.org/will/kvmtool/c/7e19cb54a7cc [20/22] arm: Reorganise and document memory map https://git.kernel.org/will/kvmtool/c/f01cc778bd65 [21/22] hw/serial: ARM/arm64: Use MMIO at higher addresses https://git.kernel.org/will/kvmtool/c/45b4968e0de1 [22/22] hw/rtc: ARM/arm64: Use MMIO at higher addresses https://git.kernel.org/will/kvmtool/c/382eaad7b695 Cheers,
Hi, this version is addressing Alexandru's comments, fixing mostly minor issues in the naming scheme. The biggest change is to keep the ioport__read/ioport_write wrappers for the serial device. For more details see the changelog below. ============== At the moment we use two separate code paths to handle exits for KVM_EXIT_IO (ioport.c) and KVM_EXIT_MMIO (mmio.c), even though they are semantically very similar. Because the trap handler callback routine is different, devices need to decide on one conduit or need to provide different handler functions for both of them. This is not only unnecessary code duplication, but makes switching devices from I/O port to MMIO a tedious task, even though there is no real difference between the two, especially on ARM and PowerPC. For ARM we aim at providing a flexible memory layout, and also have trouble with the UART and RTC device overlapping with the PCI I/O area, so it seems indicated to tackle this once and for all. The first three patches do some cleanup, to simplify things later. Patch 04/22 lays the groundwork, by extending mmio.c to be able to also register I/O port trap handlers, using the same callback prototype as we use for MMIO. The next 14 patches then convert devices that use the I/O port interface over to the new joint interface. This requires to rework the trap handler routine to adhere to the same prototype as the existing MMIO handlers. For most devices this is done in two steps: a first to introduce the reworked handler routine, and a second to switch to the new joint registration routine. For some devices the first step is trivial, so it's done in one patch. Patch 19/22 then retires the old I/O port interface, by removing ioport.c and friends. Patch 20/22 uses the opportunity to clean up the memory map description, also declares a new region (from 16MB on), where the final two patches switch the UART and the RTC device to. They are now registered on the MMIO "bus", when running on ARM or arm64. This moves them away from the first 64KB, so they are not in the PCI I/O area anymore. Please have a look and comment! Cheers, Andre Changelog v2 .. v3: - use _io as function prefix for x86 I/O port devices - retain ioport__{read,write}8() wrappers for serial device - fix memory map ASCII art - fix serial base declaration - minor nit fixes - add Reviewed-by: tags Changelog v1 .. v2: - rework memory map definition - add explicit debug output for debug I/O port - add explicit check for MMIO coalescing on I/O ports - drop usage of ioport__{read,write}8() from serial - drop explicit I/O port cleanup routine (to mimic MMIO operation) - add comment for IOTRAP_BUS_MASK - minor cleanups / formatting changes Andre Przywara (22): ioport: Remove ioport__setup_arch() hw/serial: Use device abstraction for FDT generator function ioport: Retire .generate_fdt_node functionality mmio: Extend handling to include ioport emulation hw/i8042: Clean up data types hw/i8042: Refactor trap handler hw/i8042: Switch to new trap handlers x86/ioport: Refactor trap handlers x86/ioport: Switch to new trap handlers hw/rtc: Refactor trap handlers hw/rtc: Switch to new trap handler hw/vesa: Switch trap handling to use MMIO handler hw/serial: Refactor trap handler hw/serial: Switch to new trap handlers vfio: Refactor ioport trap handler vfio: Switch to new ioport trap handlers virtio: Switch trap handling to use MMIO handler pci: Switch trap handling to use MMIO handler Remove ioport specific routines arm: Reorganise and document memory map hw/serial: ARM/arm64: Use MMIO at higher addresses hw/rtc: ARM/arm64: Use MMIO at higher addresses Makefile | 1 - arm/include/arm-common/kvm-arch.h | 47 ++++-- arm/ioport.c | 5 - hw/i8042.c | 94 +++++------- hw/rtc.c | 91 ++++++------ hw/serial.c | 126 +++++++++++----- hw/vesa.c | 19 +-- include/kvm/i8042.h | 1 - include/kvm/ioport.h | 32 ---- include/kvm/kvm.h | 49 ++++++- ioport.c | 235 ------------------------------ mips/kvm.c | 5 - mmio.c | 65 +++++++-- pci.c | 82 +++-------- powerpc/ioport.c | 6 - vfio/core.c | 50 ++++--- virtio/pci.c | 46 ++---- x86/ioport.c | 108 +++++++------- 18 files changed, 421 insertions(+), 641 deletions(-) delete mode 100644 ioport.c