[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [no subject]
From: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx> Date: Sat, 28 Nov 2020 22:33:51 +0200 Subject: [PATCH V3 00/23] IOREQ feature (+ virtio-mmio) on Arm MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hello all. The purpose of this patch series is to add IOREQ/DM support to Xen on Arm. You can find an initial discussion at [1] and RFC/V1/V2 series at [2]/[3]/[4]. Xen on Arm requires some implementation to forward guest MMIO access to a device model in order to implement virtio-mmio backend or even mediator outside of hypervisor. As Xen on x86 already contains required support this series tries to make it common and introduce Arm specific bits plus some new functionality. Patch series is based on Julien's PoC "xen/arm: Add support for Guest IO forwarding to a device emulator". Besides splitting existing IOREQ/DM support and introducing Arm side, the series also includes virtio-mmio related changes (last 2 patches for toolstack) for the reviewers to be able to see how the whole picture could look like. According to the initial discussion there are a few open questions/concerns regarding security, performance in VirtIO solution: 1. virtio-mmio vs virtio-pci, SPI vs MSI, different use-cases require different transport... 2. virtio backend is able to access all guest memory, some kind of protection is needed: 'virtio-iommu in Xen' vs 'pre-shared-memory & memcpys in guest' 3. interface between toolstack and 'out-of-qemu' virtio backend, avoid using Xenstore in virtio backend if possible. 4. a lot of 'foreing mapping' could lead to the memory exhaustion, Julien has some idea regarding that. Looks like all of them are valid and worth considering, but the first thing which we need on Arm is a mechanism to forward guest IO to a device emulator, so let's focus on it in the first place. *** There are a lot of changes since RFC series, almost all TODOs were resolved on Arm, Arm code was improved and hardened, common IOREQ/DM code became really arch-agnostic (without HVM-ism), the "legacy" mechanism of mapping magic pages for the IOREQ servers was left x86 specific, etc. But one TODO still remains which is "PIO handling" on Arm. The "PIO handling" TODO is expected to left unaddressed for the current series. It is not an big issue for now while Xen doesn't have support for vPCI on Arm. On Arm64 they are only used for PCI IO Bar and we would probably want to expose them to emulator as PIO access to make a DM completely arch-agnostic. So "PIO handling" should be implemented when we add support for vPCI. I left interface untouched in the following patch "xen/dm: Introduce xendevicemodel_set_irq_level DM op" since there is still an open discussion what interface to use/what information to pass to the hypervisor. There is a patch on review this series depends on: https://patchwork.kernel.org/patch/11816689 Please note, that IOREQ feature is disabled by default on Arm within current series. *** Patch series [5] was rebased on recent "staging branch" (181f2c2 evtchn: double per-channel locking can't hit identical channels) and tested on Renesas Salvator-X board + H3 ES3.0 SoC (Arm64) with virtio-mmio disk backend [6] running in driver domain and unmodified Linux Guest running on existing virtio-blk driver (frontend). No issues were observed. Guest domain 'reboot/destroy' use-cases work properly. Patch series was only build-tested on x86. Please note, build-test passed for the following modes: 1. x86: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) 2. x86: #CONFIG_HVM is not set / #CONFIG_IOREQ_SERVER is not set 3. Arm64: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y 4. Arm64: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set (default) 5. Arm32: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y 6. Arm32: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set (default) *** Any feedback/help would be highly appreciated. [1] https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg00825.html [2] https://lists.xenproject.org/archives/html/xen-devel/2020-08/msg00071.html [3] https://lists.xenproject.org/archives/html/xen-devel/2020-09/msg00732.html [4] https://lists.xenproject.org/archives/html/xen-devel/2020-10/msg01077.html [5] https://github.com/otyshchenko1/xen/commits/ioreq_4.14_ml4 [6] https://github.com/xen-troops/virtio-disk/commits/ioreq_ml1 Julien Grall (5): xen/dm: Make x86's DM feature common xen/mm: Make x86's XENMEM_resource_ioreq_server handling common arm/ioreq: Introduce arch specific bits for IOREQ/DM features xen/dm: Introduce xendevicemodel_set_irq_level DM op libxl: Introduce basic virtio-mmio support on Arm Oleksandr Tyshchenko (18): x86/ioreq: Prepare IOREQ feature for making it common x86/ioreq: Add IOREQ_STATUS_* #define-s and update code for moving x86/ioreq: Provide out-of-line wrapper for the handle_mmio() xen/ioreq: Make x86's IOREQ feature common xen/ioreq: Make x86's hvm_ioreq_needs_completion() common xen/ioreq: Make x86's hvm_mmio_first(last)_byte() common xen/ioreq: Make x86's hvm_ioreq_(page/vcpu/server) structs common xen/ioreq: Move x86's ioreq_server to struct domain xen/ioreq: Move x86's io_completion/io_req fields to struct vcpu xen/ioreq: Remove "hvm" prefixes from involved function names xen/ioreq: Use guest_cmpxchg64() instead of cmpxchg() xen/arm: Stick around in leave_hypervisor_to_guest until I/O has completed xen/mm: Handle properly reference in set_foreign_p2m_entry() on Arm xen/ioreq: Introduce domain_has_ioreq_server() xen/arm: io: Abstract sign-extension xen/ioreq: Make x86's send_invalidate_req() common xen/arm: Add mapcache invalidation handling [RFC] libxl: Add support for virtio-disk configuration MAINTAINERS | 8 +- tools/include/xendevicemodel.h | 4 + tools/libs/devicemodel/core.c | 18 + tools/libs/devicemodel/libxendevicemodel.map | 1 + tools/libs/light/Makefile | 1 + tools/libs/light/libxl_arm.c | 94 +- tools/libs/light/libxl_create.c | 1 + tools/libs/light/libxl_internal.h | 1 + tools/libs/light/libxl_types.idl | 16 + tools/libs/light/libxl_types_internal.idl | 1 + tools/libs/light/libxl_virtio_disk.c | 109 +++ tools/xl/Makefile | 2 +- tools/xl/xl.h | 3 + tools/xl/xl_cmdtable.c | 15 + tools/xl/xl_parse.c | 116 +++ tools/xl/xl_virtio_disk.c | 46 + xen/arch/arm/Makefile | 2 + xen/arch/arm/dm.c | 89 ++ xen/arch/arm/domain.c | 9 + xen/arch/arm/hvm.c | 4 + xen/arch/arm/io.c | 29 +- xen/arch/arm/ioreq.c | 126 +++ xen/arch/arm/p2m.c | 48 +- xen/arch/arm/traps.c | 58 +- xen/arch/x86/Kconfig | 1 + xen/arch/x86/hvm/dm.c | 295 +----- xen/arch/x86/hvm/emulate.c | 80 +- xen/arch/x86/hvm/hvm.c | 12 +- xen/arch/x86/hvm/hypercall.c | 9 +- xen/arch/x86/hvm/intercept.c | 5 +- xen/arch/x86/hvm/io.c | 26 +- xen/arch/x86/hvm/ioreq.c | 1357 ++------------------------ xen/arch/x86/hvm/stdvga.c | 10 +- xen/arch/x86/hvm/svm/nestedsvm.c | 2 +- xen/arch/x86/hvm/vmx/realmode.c | 6 +- xen/arch/x86/hvm/vmx/vvmx.c | 2 +- xen/arch/x86/mm.c | 46 +- xen/arch/x86/mm/p2m.c | 13 +- xen/arch/x86/mm/shadow/common.c | 2 +- xen/common/Kconfig | 3 + xen/common/Makefile | 2 + xen/common/dm.c | 292 ++++++ xen/common/ioreq.c | 1307 +++++++++++++++++++++++++ xen/common/memory.c | 73 +- xen/include/asm-arm/domain.h | 3 + xen/include/asm-arm/hvm/ioreq.h | 139 +++ xen/include/asm-arm/mm.h | 8 - xen/include/asm-arm/mmio.h | 1 + xen/include/asm-arm/p2m.h | 19 +- xen/include/asm-arm/traps.h | 24 + xen/include/asm-x86/hvm/domain.h | 43 - xen/include/asm-x86/hvm/emulate.h | 2 +- xen/include/asm-x86/hvm/io.h | 17 - xen/include/asm-x86/hvm/ioreq.h | 58 +- xen/include/asm-x86/hvm/vcpu.h | 18 - xen/include/asm-x86/mm.h | 4 - xen/include/asm-x86/p2m.h | 24 +- xen/include/public/arch-arm.h | 5 + xen/include/public/hvm/dm_op.h | 16 + xen/include/xen/dm.h | 44 + xen/include/xen/ioreq.h | 146 +++ xen/include/xen/p2m-common.h | 4 + xen/include/xen/sched.h | 32 + xen/include/xsm/dummy.h | 4 +- xen/include/xsm/xsm.h | 6 +- xen/xsm/dummy.c | 2 +- xen/xsm/flask/hooks.c | 5 +- 67 files changed, 3084 insertions(+), 1884 deletions(-) create mode 100644 tools/libs/light/libxl_virtio_disk.c create mode 100644 tools/xl/xl_virtio_disk.c create mode 100644 xen/arch/arm/dm.c create mode 100644 xen/arch/arm/ioreq.c create mode 100644 xen/common/dm.c create mode 100644 xen/common/ioreq.c create mode 100644 xen/include/asm-arm/hvm/ioreq.h create mode 100644 xen/include/xen/dm.h create mode 100644 xen/include/xen/ioreq.h -- 2.7.4
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |