| Message ID | 1584200119-18594-1-git-send-email-mikelley@microsoft.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Subject: Enable Linux guests on Hyper-V on ARM64 | expand |
On Sat, 14 Mar 2020 08:35:12 -0700 Michael Kelley wrote: > +/* > + * Get the value of a single VP register. One version > + * returns just 64 bits and another returns the full 128 bits. > + * The two versions are separate to avoid complicating the > + * calling sequence for the more frequently used 64 bit version. > + */ > + > +/* > + * Input and output memory allocation sizes are rounded up to a power > + * of 2 so kmalloc() will guarantee alignment. In turn, the alignment > + * ensures that the allocations don't cross a page boundary, which is Better to specify kmalloc's current alignment and why it fails to ensure (4 * sizeof(u64))-sized allocations wont cross page boundary. > + * required by the hypercall interface. > + */ > +#define INPUTSIZE (4 * sizeof(u64)) > +#define OUTPUTSIZE (2 * sizeof(u64)) > + > +static void __hv_get_vpreg_128(u32 msr, struct hv_get_vp_register_output *res) > +{ > + union hv_hypercall_status status; > + struct hv_get_vp_register_input *input; > + > + BUILD_BUG_ON(sizeof(*input) > INPUTSIZE); > + > + input = kzalloc(INPUTSIZE, GFP_ATOMIC); > + > + input->partitionid = HV_PARTITION_ID_SELF; > + input->vpindex = HV_VP_INDEX_SELF; > + input->inputvtl = 0; > + input->name0 = msr; > + input->name1 = 0; > + > + > + status.as_uint64 = hv_do_hypercall( > + HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_REP_COUNT_1, > + input, res); > + > + /* > + * Something is fundamentally broken in the hypervisor if > + * getting a VP register fails. There's really no way to > + * continue as a guest VM, so panic. > + */ > + BUG_ON(status.status != HV_STATUS_SUCCESS); > + > + kfree(input); > +}
From: Hillf Danton <hdanton@sina.com> Sent: Tuesday, March 17, 2020 8:12 PM > > On Sat, 14 Mar 2020 08:35:12 -0700 Michael Kelley wrote: > > +/* > > + * Get the value of a single VP register. One version > > + * returns just 64 bits and another returns the full 128 bits. > > + * The two versions are separate to avoid complicating the > > + * calling sequence for the more frequently used 64 bit version. > > + */ > > + > > +/* > > + * Input and output memory allocation sizes are rounded up to a power > > + * of 2 so kmalloc() will guarantee alignment. In turn, the alignment > > + * ensures that the allocations don't cross a page boundary, which is > > Better to specify kmalloc's current alignment and why it fails to ensure > (4 * sizeof(u64))-sized allocations wont cross page boundary. > Is your comment referring to ARCH_KMALLOC_MINALIGN? If so, I see how that makes sense. BUILD_BUG_ON (sizeof (*input) > ARCH_KMALLOC_MINALIGN) would be a cleaner solution. Thanks, Michael > > + * required by the hypercall interface. > > + */ > > +#define INPUTSIZE (4 * sizeof(u64)) > > +#define OUTPUTSIZE (2 * sizeof(u64)) > > + > > +static void __hv_get_vpreg_128(u32 msr, struct hv_get_vp_register_output *res) > > +{ > > + union hv_hypercall_status status; > > + struct hv_get_vp_register_input *input; > > + > > + BUILD_BUG_ON(sizeof(*input) > INPUTSIZE); > > + > > + input = kzalloc(INPUTSIZE, GFP_ATOMIC); > > + > > + input->partitionid = HV_PARTITION_ID_SELF; > > + input->vpindex = HV_VP_INDEX_SELF; > > + input->inputvtl = 0; > > + input->name0 = msr; > > + input->name1 = 0; > > + > > + > > + status.as_uint64 = hv_do_hypercall( > > + HVCALL_GET_VP_REGISTERS | HV_HYPERCALL_REP_COUNT_1, > > + input, res); > > + > > + /* > > + * Something is fundamentally broken in the hypervisor if > > + * getting a VP register fails. There's really no way to > > + * continue as a guest VM, so panic. > > + */ > > + BUG_ON(status.status != HV_STATUS_SUCCESS); > > + > > + kfree(input); > > +}
This series enables Linux guests running on Hyper-V on ARM64 hardware. New ARM64-specific code in arch/arm64/hyperv initializes Hyper-V, including its interrupts and hypercall mechanism. Existing architecture independent drivers for Hyper-V's VMbus and synthetic devices just work when built for ARM64. Hyper-V code is built and included in the image and modules only if CONFIG_HYPERV is enabled. The ten patches are organized as follows: 1) Add include files that define the Hyper-V interface as described in the Hyper-V Top Level Functional Spec (TLFS), plus additional definitions specific to Linux running on Hyper-V. 2) Add #define for vendor specific owner definition to linux/arm-smccc.h 3) thru 7) Add core Hyper-V support on ARM64, including hypercalls, interrupt handlers, kexec & panic handlers, and core hypervisor initialization. 8) Update the existing VMbus driver to generalize interrupt management across x86/x64 and ARM64. 9) Export screen_info so it may be used by the Hyper-V frame buffer driver built as a module. It's already exported for x86, powerpc, and alpha architectures. 10) Make CONFIG_HYPERV selectable on ARM64 in addition to x86/x64. Some areas of Linux guests on Hyper-V on ARM64 are a work- in-progress: * Hyper-V on ARM64 currently runs with a 4 Kbyte page size, but allows guests with 16K/64K page size. However, the Linux drivers for Hyper-V synthetic devices assume the guest page size is 4K. This patch set lays the groundwork for larger guest page sizes, but additional patches are coming to update these drivers. * The Hyper-V vPCI driver at drivers/pci/host/pci-hyperv.c has x86/x64-specific code and is not being built for ARM64. Fixing this driver to enable vPCI devices on ARM64 will be done later. In a few cases, terminology from the x86/x64 world has been carried over into the ARM64 code ("MSR", "TSC"). Hyper-V still uses the x86/x64 terminology and has not replaced it with something more generic, so the code uses the Hyper-V terminology. This will be fixed when Hyper-V updates the usage in the TLFS. This patch set is based on a 5.6-rc5 linux-next tree. Changes in v6: * Use SMCCC hypercall interface instead of direct invocation of HVC instruction and the Hyper-V hypercall interface [Marc Zyngier] * Reimplemented functions to alloc/free Hyper-V size pages using kmalloc/kfree since kmalloc now guarantees alignment of power of 2 size allocations [Marc Zyngier] * Export screen_info in arm64 architecture so it can be used by the Hyper-V buffer driver built as a module * Renamed source file arch/arm64/hyperv/hv_init.c to hv_core.c to better reflect its content * Fixed the bit position of certain feature flags presented by Hyper-V to the guest. The bit positions on ARM64 don't match the position on x86 like originally thought. * Minor fixups to rebase to 5.6-rc5 linux-next Changes in v5: * Minor fixups to rebase to 5.4-rc1 linux-next Changes in v4: * Moved clock-related code into an architecture independent Hyper-V clocksource driver that is already upstream. Clock related code is removed from this patch set except for the ARM64 specific interrupt handler. [Marc Zyngier] * Separately upstreamed the split of mshyperv.h into arch independent and arch dependent portions. The arch independent portion has been removed from this patch set. * Divided patch #2 of the series into multiple smaller patches [Marc Zyngier] * Changed a dozen or so smaller things based on feedback [Marc Zyngier, Will Deacon] * Added functions to alloc/free Hyper-V size pages for use by drivers for Hyper-V synthetic devices when updated to not assume guest page size and Hyper-v page size are the same Changes in v3: * Added initialization of hv_vp_index array like was recently added on x86 branch [KY Srinivasan] * Changed Hyper-V ARM64 register symbols to be all uppercase instead of mixed case [KY Srinivasan] * Separated mshyperv.h into two files, one architecture independent and one architecture dependent. After this code is upstream, will make changes to the x86 code to use the architecture independent file and remove duplication. And once we have a multi-architecture Hyper-V TLFS, will do a separate patch to split hyperv-tlfs.h in the same way. [KY Srinivasan] * Minor tweaks to rebase to latest linux-next code Changes in v2: * Removed patch to implement slow_virt_to_phys() on ARM64. Use of slow_virt_to_phys() in arch independent Hyper-V drivers has been eliminated by commit 6ba34171bcbd ("Drivers: hv: vmbus: Remove use of slow_virt_to_phys()") * Minor tweaks to rebase to latest linux-next code Michael Kelley (10): arm64: hyperv: Add core Hyper-V include files arm/arm64: smccc-1.1: Add vendor specific owner definition arm64: hyperv: Add hypercall and register access functions arm64: hyperv: Add memory alloc/free functions for Hyper-V size pages arm64: hyperv: Add interrupt handlers for VMbus and stimer arm64: hyperv: Add kexec and panic handlers arm64: hyperv: Initialize hypervisor on boot Drivers: hv: vmbus: Add hooks for per-CPU IRQ arm64: efi: Export screen_info Drivers: hv: Enable Hyper-V code to be built on ARM64 MAINTAINERS | 3 + arch/arm64/Kbuild | 1 + arch/arm64/hyperv/Makefile | 2 + arch/arm64/hyperv/hv_core.c | 418 +++++++++++++++++++++++++++++++++++ arch/arm64/hyperv/mshyperv.c | 165 ++++++++++++++ arch/arm64/include/asm/hyperv-tlfs.h | 413 ++++++++++++++++++++++++++++++++++ arch/arm64/include/asm/mshyperv.h | 115 ++++++++++ arch/arm64/kernel/efi.c | 1 + arch/x86/include/asm/mshyperv.h | 4 + drivers/hv/Kconfig | 3 +- drivers/hv/hv.c | 3 + include/asm-generic/mshyperv.h | 5 + include/linux/arm-smccc.h | 1 + 13 files changed, 1133 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/hyperv/Makefile create mode 100644 arch/arm64/hyperv/hv_core.c create mode 100644 arch/arm64/hyperv/mshyperv.c create mode 100644 arch/arm64/include/asm/hyperv-tlfs.h create mode 100644 arch/arm64/include/asm/mshyperv.h