[PATCH 02/10] x86: jailhouse: Add infrastructure for running in non-root cell
From: Jan Kiszka
Date: Thu Nov 16 2017 - 02:36:28 EST
From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
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 <jan.kiszka@xxxxxxxxxxx>
---
arch/x86/Kconfig | 12 ++++++
arch/x86/include/asm/hypervisor.h | 1 +
arch/x86/include/asm/jailhouse_para.h | 27 +++++++++++++
arch/x86/kernel/Makefile | 2 +
arch/x86/kernel/cpu/hypervisor.c | 4 ++
arch/x86/kernel/jailhouse.c | 76 +++++++++++++++++++++++++++++++++++
6 files changed, 122 insertions(+)
create mode 100644 arch/x86/include/asm/jailhouse_para.h
create mode 100644 arch/x86/kernel/jailhouse.c
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index df3276d6bfe3..c5f4f4683b51 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -782,6 +782,18 @@ config KVM_DEBUG_FS
Statistics are displayed in debugfs filesystem. Enabling this option
may incur significant overhead.
+config JAILHOUSE_GUEST
+ bool "Jailhouse non-root cell support"
+ depends on PARAVIRT && X86_64
+ ---help---
+ This option allows to run Linux as guest in a Jailhouse non-root
+ cell. You can leave this option disabled if you only want to start
+ Jailhouse and run Linux afterwards in the root cell.
+
+ You likely also want to disable CONFIG_SUSPEND and CONFIG_SERIO to
+ avoid access to I/O resources that are usually not assigned to the
+ non-root cell.
+
config PARAVIRT_TIME_ACCOUNTING
bool "Paravirtual steal time accounting"
depends on PARAVIRT
diff --git a/arch/x86/include/asm/hypervisor.h b/arch/x86/include/asm/hypervisor.h
index 1b0a5abcd8ae..376085cb6244 100644
--- a/arch/x86/include/asm/hypervisor.h
+++ b/arch/x86/include/asm/hypervisor.h
@@ -37,6 +37,7 @@ enum x86_hypervisor_type {
X86_HYPER_XEN_PV,
X86_HYPER_XEN_HVM,
X86_HYPER_KVM,
+ X86_HYPER_JAILHOUSE,
};
struct hypervisor_x86 {
diff --git a/arch/x86/include/asm/jailhouse_para.h b/arch/x86/include/asm/jailhouse_para.h
new file mode 100644
index 000000000000..06a5f41d5451
--- /dev/null
+++ b/arch/x86/include/asm/jailhouse_para.h
@@ -0,0 +1,27 @@
+/*
+ * Jailhouse paravirt_ops implementation
+ *
+ * Copyright (c) Siemens AG, 2015-2017
+ *
+ * Authors:
+ * Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#ifndef _ASM_X86_JAILHOUSE_PARA_H
+#define _ASM_X86_JAILHOUSE_PARA_H
+
+#include <linux/types.h>
+
+#ifdef CONFIG_JAILHOUSE_GUEST
+bool jailhouse_paravirt(void);
+#else
+static inline bool jailhouse_paravirt(void)
+{
+ return false;
+}
+#endif
+
+#endif /* _ASM_X86_JAILHOUSE_PARA_H */
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 81bb565f4497..aed9296dccd3 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -112,6 +112,8 @@ obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= paravirt-spinlocks.o
obj-$(CONFIG_PARAVIRT_CLOCK) += pvclock.o
obj-$(CONFIG_X86_PMEM_LEGACY_DEVICE) += pmem.o
+obj-$(CONFIG_JAILHOUSE_GUEST) += jailhouse.o
+
obj-$(CONFIG_EISA) += eisa.o
obj-$(CONFIG_PCSPKR_PLATFORM) += pcspeaker.o
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index bea8d3e24f50..479ca4728de0 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -31,6 +31,7 @@ extern const struct hypervisor_x86 x86_hyper_ms_hyperv;
extern const struct hypervisor_x86 x86_hyper_xen_pv;
extern const struct hypervisor_x86 x86_hyper_xen_hvm;
extern const struct hypervisor_x86 x86_hyper_kvm;
+extern const struct hypervisor_x86 x86_hyper_jailhouse;
static const __initconst struct hypervisor_x86 * const hypervisors[] =
{
@@ -45,6 +46,9 @@ static const __initconst struct hypervisor_x86 * const hypervisors[] =
#ifdef CONFIG_KVM_GUEST
&x86_hyper_kvm,
#endif
+#ifdef CONFIG_JAILHOUSE_GUEST
+ &x86_hyper_jailhouse,
+#endif
};
enum x86_hypervisor_type x86_hyper_type;
diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c
new file mode 100644
index 000000000000..bc0f49a6172d
--- /dev/null
+++ b/arch/x86/kernel/jailhouse.c
@@ -0,0 +1,76 @@
+/*
+ * Jailhouse paravirt_ops implementation
+ *
+ * Copyright (c) Siemens AG, 2015-2017
+ *
+ * Authors:
+ * Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <linux/kernel.h>
+#include <asm/cpu.h>
+#include <asm/hypervisor.h>
+#include <asm/setup.h>
+
+#define SETUP_JAILHOUSE 0x53484c4a /* "JLHS" */
+
+#define SETUP_REQUIRED_VERSION 1
+
+/*
+ * The boot loader is passing platform information via this Jailhouse-specific
+ * setup data structure.
+ */
+struct jailhouse_setup_data {
+ struct setup_data header;
+ u16 version;
+ u16 compatible_version;
+ u16 pm_timer_address;
+ u16 num_cpus;
+ u64 pci_mmconfig_base;
+ u8 standard_ioapic;
+ u8 cpu_ids[255];
+};
+
+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 jailhouse_setup_data *data;
+
+ data = early_memremap(pa_data, sizeof(*data));
+
+ if (data->header.type != SETUP_JAILHOUSE ||
+ data->compatible_version > SETUP_REQUIRED_VERSION)
+ panic("Jailhouse: Unsupported setup data structure");
+
+ early_memunmap(data, sizeof(*data));
+}
+
+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,
+ },
+};
--
2.12.3