summaryrefslogtreecommitdiffstats
path: root/arch/x86/xen/enlighten_hvm.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/xen/enlighten_hvm.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/xen/enlighten_hvm.c')
-rw-r--r--arch/x86/xen/enlighten_hvm.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
new file mode 100644
index 000000000..c66807dd0
--- /dev/null
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -0,0 +1,336 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/acpi.h>
+#include <linux/cpu.h>
+#include <linux/kexec.h>
+#include <linux/memblock.h>
+#include <linux/virtio_anchor.h>
+
+#include <xen/features.h>
+#include <xen/events.h>
+#include <xen/hvm.h>
+#include <xen/interface/hvm/hvm_op.h>
+#include <xen/interface/memory.h>
+
+#include <asm/apic.h>
+#include <asm/cpu.h>
+#include <asm/smp.h>
+#include <asm/io_apic.h>
+#include <asm/reboot.h>
+#include <asm/setup.h>
+#include <asm/idtentry.h>
+#include <asm/hypervisor.h>
+#include <asm/e820/api.h>
+#include <asm/early_ioremap.h>
+
+#include <asm/xen/cpuid.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/page.h>
+
+#include "xen-ops.h"
+#include "mmu.h"
+#include "smp.h"
+
+static unsigned long shared_info_pfn;
+
+__ro_after_init bool xen_percpu_upcall;
+EXPORT_SYMBOL_GPL(xen_percpu_upcall);
+
+void xen_hvm_init_shared_info(void)
+{
+ struct xen_add_to_physmap xatp;
+
+ xatp.domid = DOMID_SELF;
+ xatp.idx = 0;
+ xatp.space = XENMAPSPACE_shared_info;
+ xatp.gpfn = shared_info_pfn;
+ if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
+ BUG();
+}
+
+static void __init reserve_shared_info(void)
+{
+ u64 pa;
+
+ /*
+ * Search for a free page starting at 4kB physical address.
+ * Low memory is preferred to avoid an EPT large page split up
+ * by the mapping.
+ * Starting below X86_RESERVE_LOW (usually 64kB) is fine as
+ * the BIOS used for HVM guests is well behaved and won't
+ * clobber memory other than the first 4kB.
+ */
+ for (pa = PAGE_SIZE;
+ !e820__mapped_all(pa, pa + PAGE_SIZE, E820_TYPE_RAM) ||
+ memblock_is_reserved(pa);
+ pa += PAGE_SIZE)
+ ;
+
+ shared_info_pfn = PHYS_PFN(pa);
+
+ memblock_reserve(pa, PAGE_SIZE);
+ HYPERVISOR_shared_info = early_memremap(pa, PAGE_SIZE);
+}
+
+static void __init xen_hvm_init_mem_mapping(void)
+{
+ early_memunmap(HYPERVISOR_shared_info, PAGE_SIZE);
+ HYPERVISOR_shared_info = __va(PFN_PHYS(shared_info_pfn));
+
+ /*
+ * The virtual address of the shared_info page has changed, so
+ * the vcpu_info pointer for VCPU 0 is now stale.
+ *
+ * The prepare_boot_cpu callback will re-initialize it via
+ * xen_vcpu_setup, but we can't rely on that to be called for
+ * old Xen versions (xen_have_vector_callback == 0).
+ *
+ * It is, in any case, bad to have a stale vcpu_info pointer
+ * so reset it now.
+ */
+ xen_vcpu_info_reset(0);
+}
+
+static void __init init_hvm_pv_info(void)
+{
+ int major, minor;
+ uint32_t eax, ebx, ecx, edx, base;
+
+ base = xen_cpuid_base();
+ eax = cpuid_eax(base + 1);
+
+ major = eax >> 16;
+ minor = eax & 0xffff;
+ printk(KERN_INFO "Xen version %d.%d.\n", major, minor);
+
+ xen_domain_type = XEN_HVM_DOMAIN;
+
+ /* PVH set up hypercall page in xen_prepare_pvh(). */
+ if (xen_pvh_domain())
+ pv_info.name = "Xen PVH";
+ else {
+ u64 pfn;
+ uint32_t msr;
+
+ pv_info.name = "Xen HVM";
+ msr = cpuid_ebx(base + 2);
+ pfn = __pa(hypercall_page);
+ wrmsr_safe(msr, (u32)pfn, (u32)(pfn >> 32));
+ }
+
+ xen_setup_features();
+
+ cpuid(base + 4, &eax, &ebx, &ecx, &edx);
+ if (eax & XEN_HVM_CPUID_VCPU_ID_PRESENT)
+ this_cpu_write(xen_vcpu_id, ebx);
+ else
+ this_cpu_write(xen_vcpu_id, smp_processor_id());
+}
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_xen_hvm_callback)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ if (xen_percpu_upcall)
+ ack_APIC_irq();
+
+ inc_irq_stat(irq_hv_callback_count);
+
+ xen_evtchn_do_upcall();
+
+ set_irq_regs(old_regs);
+}
+
+#ifdef CONFIG_KEXEC_CORE
+static void xen_hvm_shutdown(void)
+{
+ native_machine_shutdown();
+ if (kexec_in_progress)
+ xen_reboot(SHUTDOWN_soft_reset);
+}
+
+static void xen_hvm_crash_shutdown(struct pt_regs *regs)
+{
+ native_machine_crash_shutdown(regs);
+ xen_reboot(SHUTDOWN_soft_reset);
+}
+#endif
+
+static int xen_cpu_up_prepare_hvm(unsigned int cpu)
+{
+ int rc = 0;
+
+ /*
+ * This can happen if CPU was offlined earlier and
+ * offlining timed out in common_cpu_die().
+ */
+ if (cpu_report_state(cpu) == CPU_DEAD_FROZEN) {
+ xen_smp_intr_free(cpu);
+ xen_uninit_lock_cpu(cpu);
+ }
+
+ if (cpu_acpi_id(cpu) != U32_MAX)
+ per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu);
+ else
+ per_cpu(xen_vcpu_id, cpu) = cpu;
+ xen_vcpu_setup(cpu);
+ if (!xen_have_vector_callback)
+ return 0;
+
+ if (xen_percpu_upcall) {
+ rc = xen_set_upcall_vector(cpu);
+ if (rc) {
+ WARN(1, "HVMOP_set_evtchn_upcall_vector"
+ " for CPU %d failed: %d\n", cpu, rc);
+ return rc;
+ }
+ }
+
+ if (xen_feature(XENFEAT_hvm_safe_pvclock))
+ xen_setup_timer(cpu);
+
+ rc = xen_smp_intr_init(cpu);
+ if (rc) {
+ WARN(1, "xen_smp_intr_init() for CPU %d failed: %d\n",
+ cpu, rc);
+ }
+ return rc;
+}
+
+static int xen_cpu_dead_hvm(unsigned int cpu)
+{
+ xen_smp_intr_free(cpu);
+
+ if (xen_have_vector_callback && xen_feature(XENFEAT_hvm_safe_pvclock))
+ xen_teardown_timer(cpu);
+ return 0;
+}
+
+static void __init xen_hvm_guest_init(void)
+{
+ if (xen_pv_domain())
+ return;
+
+ if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
+ virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
+
+ init_hvm_pv_info();
+
+ reserve_shared_info();
+ xen_hvm_init_shared_info();
+
+ /*
+ * xen_vcpu is a pointer to the vcpu_info struct in the shared_info
+ * page, we use it in the event channel upcall and in some pvclock
+ * related functions.
+ */
+ xen_vcpu_info_reset(0);
+
+ xen_panic_handler_init();
+
+ xen_hvm_smp_init();
+ WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm));
+ xen_unplug_emulated_devices();
+ x86_init.irqs.intr_init = xen_init_IRQ;
+ xen_hvm_init_time_ops();
+ xen_hvm_init_mmu_ops();
+
+#ifdef CONFIG_KEXEC_CORE
+ machine_ops.shutdown = xen_hvm_shutdown;
+ machine_ops.crash_shutdown = xen_hvm_crash_shutdown;
+#endif
+}
+
+static __init int xen_parse_nopv(char *arg)
+{
+ pr_notice("\"xen_nopv\" is deprecated, please use \"nopv\" instead\n");
+
+ if (xen_cpuid_base())
+ nopv = true;
+ return 0;
+}
+early_param("xen_nopv", xen_parse_nopv);
+
+static __init int xen_parse_no_vector_callback(char *arg)
+{
+ xen_have_vector_callback = false;
+ return 0;
+}
+early_param("xen_no_vector_callback", xen_parse_no_vector_callback);
+
+static __init bool xen_x2apic_available(void)
+{
+ return x2apic_supported();
+}
+
+static bool __init msi_ext_dest_id(void)
+{
+ return cpuid_eax(xen_cpuid_base() + 4) & XEN_HVM_CPUID_EXT_DEST_ID;
+}
+
+static __init void xen_hvm_guest_late_init(void)
+{
+#ifdef CONFIG_XEN_PVH
+ /* Test for PVH domain (PVH boot path taken overrides ACPI flags). */
+ if (!xen_pvh &&
+ (x86_platform.legacy.rtc || !x86_platform.legacy.no_vga))
+ return;
+
+ /* PVH detected. */
+ xen_pvh = true;
+
+ if (nopv)
+ panic("\"nopv\" and \"xen_nopv\" parameters are unsupported in PVH guest.");
+
+ /* Make sure we don't fall back to (default) ACPI_IRQ_MODEL_PIC. */
+ if (!nr_ioapics && acpi_irq_model == ACPI_IRQ_MODEL_PIC)
+ acpi_irq_model = ACPI_IRQ_MODEL_PLATFORM;
+
+ machine_ops.emergency_restart = xen_emergency_restart;
+ pv_info.name = "Xen PVH";
+#endif
+}
+
+static uint32_t __init xen_platform_hvm(void)
+{
+ uint32_t xen_domain = xen_cpuid_base();
+ struct x86_hyper_init *h = &x86_hyper_xen_hvm.init;
+
+ if (xen_pv_domain())
+ return 0;
+
+ if (xen_pvh_domain() && nopv) {
+ /* Guest booting via the Xen-PVH boot entry goes here */
+ pr_info("\"nopv\" parameter is ignored in PVH guest\n");
+ nopv = false;
+ } else if (nopv && xen_domain) {
+ /*
+ * Guest booting via normal boot entry (like via grub2) goes
+ * here.
+ *
+ * Use interface functions for bare hardware if nopv,
+ * xen_hvm_guest_late_init is an exception as we need to
+ * detect PVH and panic there.
+ */
+ h->init_platform = x86_init_noop;
+ h->x2apic_available = bool_x86_init_noop;
+ h->init_mem_mapping = x86_init_noop;
+ h->init_after_bootmem = x86_init_noop;
+ h->guest_late_init = xen_hvm_guest_late_init;
+ x86_hyper_xen_hvm.runtime.pin_vcpu = x86_op_int_noop;
+ }
+ return xen_domain;
+}
+
+struct hypervisor_x86 x86_hyper_xen_hvm __initdata = {
+ .name = "Xen HVM",
+ .detect = xen_platform_hvm,
+ .type = X86_HYPER_XEN_HVM,
+ .init.init_platform = xen_hvm_guest_init,
+ .init.x2apic_available = xen_x2apic_available,
+ .init.init_mem_mapping = xen_hvm_init_mem_mapping,
+ .init.guest_late_init = xen_hvm_guest_late_init,
+ .init.msi_ext_dest_id = msi_ext_dest_id,
+ .runtime.pin_vcpu = xen_pin_vcpu,
+ .ignore_nopv = true,
+};