From 4a362601baa6fff92b576d85199f1948cec2fb3b Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Mon, 27 Nov 2017 09:11:46 +0100 Subject: x86/jailhouse: Add infrastructure for running in non-root cell The Jailhouse hypervisor is able to statically partition a multicore system into multiple so-called cells. Linux is used as boot loader and continues to run in the root cell after Jailhouse is enabled. Linux can also run in non-root cells. Jailhouse does not emulate usual x86 devices. It also provides no complex ACPI but basic platform information that the boot loader forwards via setup data. This adds the infrastructure to detect when running in a non-root cell so that the platform can be configured as required in succeeding steps. Support is limited to x86-64 so far, primarily because no boot loader stub exists for i386 and, thus, we wouldn't be able to test the 32-bit path. Signed-off-by: Jan Kiszka Signed-off-by: Thomas Gleixner Cc: jailhouse-dev@googlegroups.com Link: https://lkml.kernel.org/r/7f823d077b38b1a70c526b40b403f85688c137d3.1511770314.git.jan.kiszka@siemens.com --- arch/x86/kernel/jailhouse.c | 73 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 arch/x86/kernel/jailhouse.c (limited to 'arch/x86/kernel/jailhouse.c') diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c new file mode 100644 index 000000000000..1186b8909595 --- /dev/null +++ b/arch/x86/kernel/jailhouse.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL2.0 +/* + * Jailhouse paravirt_ops implementation + * + * Copyright (c) Siemens AG, 2015-2017 + * + * Authors: + * Jan Kiszka + */ + +#include +#include +#include +#include + +static __initdata struct jailhouse_setup_data setup_data; + +static uint32_t jailhouse_cpuid_base(void) +{ + if (boot_cpu_data.cpuid_level < 0 || + !boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return 0; + + return hypervisor_cpuid_base("Jailhouse\0\0\0", 0); +} + +static uint32_t __init jailhouse_detect(void) +{ + return jailhouse_cpuid_base(); +} + +static void __init jailhouse_init_platform(void) +{ + u64 pa_data = boot_params.hdr.setup_data; + struct setup_data header; + void *mapping; + + while (pa_data) { + mapping = early_memremap(pa_data, sizeof(header)); + memcpy(&header, mapping, sizeof(header)); + early_memunmap(mapping, sizeof(header)); + + if (header.type == SETUP_JAILHOUSE && + header.len >= sizeof(setup_data)) { + pa_data += offsetof(struct setup_data, data); + + mapping = early_memremap(pa_data, sizeof(setup_data)); + memcpy(&setup_data, mapping, sizeof(setup_data)); + early_memunmap(mapping, sizeof(setup_data)); + + break; + } + + pa_data = header.next; + } + + if (!pa_data) + panic("Jailhouse: No valid setup data found"); + + if (setup_data.compatible_version > JAILHOUSE_SETUP_REQUIRED_VERSION) + panic("Jailhouse: Unsupported setup data structure"); +} + +bool jailhouse_paravirt(void) +{ + return jailhouse_cpuid_base() != 0; +} + +const struct hypervisor_x86 x86_hyper_jailhouse __refconst = { + .name = "Jailhouse", + .detect = jailhouse_detect, + .init.init_platform = jailhouse_init_platform, +}; -- cgit v1.2.3