![Jeremy Fitzhardinge](/assets/img/avatar_default.png)
Use GATE_INTERRUPT/TRAP rather than 0xe/f. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
1040 lines
24 KiB
C
1040 lines
24 KiB
C
/*
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* Core of Xen paravirt_ops implementation.
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*
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* This file contains the xen_paravirt_ops structure itself, and the
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* implementations for:
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* - privileged instructions
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* - interrupt flags
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* - segment operations
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* - booting and setup
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*
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* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/smp.h>
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#include <linux/preempt.h>
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#include <linux/hardirq.h>
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#include <linux/percpu.h>
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#include <linux/delay.h>
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#include <linux/start_kernel.h>
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#include <linux/sched.h>
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#include <linux/bootmem.h>
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#include <linux/module.h>
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#include <linux/mm.h>
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#include <linux/page-flags.h>
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#include <linux/highmem.h>
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#include <linux/console.h>
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#include <xen/interface/xen.h>
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#include <xen/interface/version.h>
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#include <xen/interface/physdev.h>
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#include <xen/interface/vcpu.h>
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#include <xen/features.h>
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#include <xen/page.h>
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#include <xen/hvc-console.h>
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#include <asm/paravirt.h>
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#include <asm/apic.h>
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#include <asm/page.h>
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#include <asm/xen/hypercall.h>
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#include <asm/xen/hypervisor.h>
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#include <asm/fixmap.h>
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#include <asm/processor.h>
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#include <asm/proto.h>
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#include <asm/msr-index.h>
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#include <asm/setup.h>
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#include <asm/desc.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include <asm/reboot.h>
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#include "xen-ops.h"
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#include "mmu.h"
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#include "multicalls.h"
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EXPORT_SYMBOL_GPL(hypercall_page);
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DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
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DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info);
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enum xen_domain_type xen_domain_type = XEN_NATIVE;
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EXPORT_SYMBOL_GPL(xen_domain_type);
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struct start_info *xen_start_info;
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EXPORT_SYMBOL_GPL(xen_start_info);
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struct shared_info xen_dummy_shared_info;
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void *xen_initial_gdt;
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/*
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* Point at some empty memory to start with. We map the real shared_info
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* page as soon as fixmap is up and running.
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*/
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struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
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/*
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* Flag to determine whether vcpu info placement is available on all
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* VCPUs. We assume it is to start with, and then set it to zero on
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* the first failure. This is because it can succeed on some VCPUs
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* and not others, since it can involve hypervisor memory allocation,
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* or because the guest failed to guarantee all the appropriate
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* constraints on all VCPUs (ie buffer can't cross a page boundary).
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*
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* Note that any particular CPU may be using a placed vcpu structure,
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* but we can only optimise if the all are.
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*
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* 0: not available, 1: available
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*/
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static int have_vcpu_info_placement = 1;
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static void xen_vcpu_setup(int cpu)
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{
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struct vcpu_register_vcpu_info info;
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int err;
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struct vcpu_info *vcpup;
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BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info);
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per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
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if (!have_vcpu_info_placement)
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return; /* already tested, not available */
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vcpup = &per_cpu(xen_vcpu_info, cpu);
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info.mfn = arbitrary_virt_to_mfn(vcpup);
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info.offset = offset_in_page(vcpup);
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printk(KERN_DEBUG "trying to map vcpu_info %d at %p, mfn %llx, offset %d\n",
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cpu, vcpup, info.mfn, info.offset);
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/* Check to see if the hypervisor will put the vcpu_info
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structure where we want it, which allows direct access via
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a percpu-variable. */
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err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
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if (err) {
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printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err);
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have_vcpu_info_placement = 0;
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} else {
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/* This cpu is using the registered vcpu info, even if
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later ones fail to. */
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per_cpu(xen_vcpu, cpu) = vcpup;
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printk(KERN_DEBUG "cpu %d using vcpu_info at %p\n",
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cpu, vcpup);
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}
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}
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/*
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* On restore, set the vcpu placement up again.
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* If it fails, then we're in a bad state, since
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* we can't back out from using it...
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*/
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void xen_vcpu_restore(void)
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{
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if (have_vcpu_info_placement) {
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int cpu;
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for_each_online_cpu(cpu) {
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bool other_cpu = (cpu != smp_processor_id());
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if (other_cpu &&
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HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL))
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BUG();
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xen_vcpu_setup(cpu);
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if (other_cpu &&
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HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL))
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BUG();
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}
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BUG_ON(!have_vcpu_info_placement);
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}
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}
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static void __init xen_banner(void)
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{
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unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL);
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struct xen_extraversion extra;
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HYPERVISOR_xen_version(XENVER_extraversion, &extra);
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printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
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pv_info.name);
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printk(KERN_INFO "Xen version: %d.%d%s%s\n",
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version >> 16, version & 0xffff, extra.extraversion,
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xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : "");
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}
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static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0;
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static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
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static void xen_cpuid(unsigned int *ax, unsigned int *bx,
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unsigned int *cx, unsigned int *dx)
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{
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unsigned maskecx = ~0;
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unsigned maskedx = ~0;
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/*
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* Mask out inconvenient features, to try and disable as many
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* unsupported kernel subsystems as possible.
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*/
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if (*ax == 1) {
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maskecx = cpuid_leaf1_ecx_mask;
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maskedx = cpuid_leaf1_edx_mask;
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}
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asm(XEN_EMULATE_PREFIX "cpuid"
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: "=a" (*ax),
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"=b" (*bx),
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"=c" (*cx),
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"=d" (*dx)
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: "0" (*ax), "2" (*cx));
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*cx &= maskecx;
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*dx &= maskedx;
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}
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static __init void xen_init_cpuid_mask(void)
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{
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unsigned int ax, bx, cx, dx;
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cpuid_leaf1_edx_mask =
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~((1 << X86_FEATURE_MCE) | /* disable MCE */
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(1 << X86_FEATURE_MCA) | /* disable MCA */
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(1 << X86_FEATURE_ACC)); /* thermal monitoring */
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if (!xen_initial_domain())
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cpuid_leaf1_edx_mask &=
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~((1 << X86_FEATURE_APIC) | /* disable local APIC */
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(1 << X86_FEATURE_ACPI)); /* disable ACPI */
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ax = 1;
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xen_cpuid(&ax, &bx, &cx, &dx);
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/* cpuid claims we support xsave; try enabling it to see what happens */
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if (cx & (1 << (X86_FEATURE_XSAVE % 32))) {
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unsigned long cr4;
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set_in_cr4(X86_CR4_OSXSAVE);
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cr4 = read_cr4();
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if ((cr4 & X86_CR4_OSXSAVE) == 0)
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cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32));
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clear_in_cr4(X86_CR4_OSXSAVE);
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}
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}
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static void xen_set_debugreg(int reg, unsigned long val)
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{
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HYPERVISOR_set_debugreg(reg, val);
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}
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static unsigned long xen_get_debugreg(int reg)
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{
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return HYPERVISOR_get_debugreg(reg);
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}
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void xen_leave_lazy(void)
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{
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paravirt_leave_lazy(paravirt_get_lazy_mode());
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xen_mc_flush();
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}
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static unsigned long xen_store_tr(void)
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{
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return 0;
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}
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/*
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* Set the page permissions for a particular virtual address. If the
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* address is a vmalloc mapping (or other non-linear mapping), then
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* find the linear mapping of the page and also set its protections to
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* match.
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*/
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static void set_aliased_prot(void *v, pgprot_t prot)
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{
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int level;
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pte_t *ptep;
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pte_t pte;
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unsigned long pfn;
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struct page *page;
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ptep = lookup_address((unsigned long)v, &level);
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BUG_ON(ptep == NULL);
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pfn = pte_pfn(*ptep);
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page = pfn_to_page(pfn);
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pte = pfn_pte(pfn, prot);
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if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
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BUG();
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if (!PageHighMem(page)) {
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void *av = __va(PFN_PHYS(pfn));
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if (av != v)
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if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
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BUG();
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} else
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kmap_flush_unused();
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}
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static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
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{
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const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
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int i;
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for(i = 0; i < entries; i += entries_per_page)
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set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
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}
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static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
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{
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const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
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int i;
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for(i = 0; i < entries; i += entries_per_page)
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set_aliased_prot(ldt + i, PAGE_KERNEL);
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}
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static void xen_set_ldt(const void *addr, unsigned entries)
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{
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struct mmuext_op *op;
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struct multicall_space mcs = xen_mc_entry(sizeof(*op));
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op = mcs.args;
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op->cmd = MMUEXT_SET_LDT;
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op->arg1.linear_addr = (unsigned long)addr;
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op->arg2.nr_ents = entries;
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MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF);
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xen_mc_issue(PARAVIRT_LAZY_CPU);
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}
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static void xen_load_gdt(const struct desc_ptr *dtr)
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{
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unsigned long va = dtr->address;
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unsigned int size = dtr->size + 1;
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unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
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unsigned long frames[pages];
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int f;
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/* A GDT can be up to 64k in size, which corresponds to 8192
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8-byte entries, or 16 4k pages.. */
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BUG_ON(size > 65536);
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BUG_ON(va & ~PAGE_MASK);
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for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) {
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int level;
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pte_t *ptep = lookup_address(va, &level);
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unsigned long pfn, mfn;
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void *virt;
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BUG_ON(ptep == NULL);
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pfn = pte_pfn(*ptep);
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mfn = pfn_to_mfn(pfn);
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virt = __va(PFN_PHYS(pfn));
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frames[f] = mfn;
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make_lowmem_page_readonly((void *)va);
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make_lowmem_page_readonly(virt);
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}
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if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct)))
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BUG();
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}
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static void load_TLS_descriptor(struct thread_struct *t,
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unsigned int cpu, unsigned int i)
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{
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struct desc_struct *gdt = get_cpu_gdt_table(cpu);
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xmaddr_t maddr = arbitrary_virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]);
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struct multicall_space mc = __xen_mc_entry(0);
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MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]);
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}
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static void xen_load_tls(struct thread_struct *t, unsigned int cpu)
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{
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/*
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* XXX sleazy hack: If we're being called in a lazy-cpu zone
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* and lazy gs handling is enabled, it means we're in a
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* context switch, and %gs has just been saved. This means we
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* can zero it out to prevent faults on exit from the
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* hypervisor if the next process has no %gs. Either way, it
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* has been saved, and the new value will get loaded properly.
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* This will go away as soon as Xen has been modified to not
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* save/restore %gs for normal hypercalls.
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*
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* On x86_64, this hack is not used for %gs, because gs points
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* to KERNEL_GS_BASE (and uses it for PDA references), so we
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* must not zero %gs on x86_64
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*
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* For x86_64, we need to zero %fs, otherwise we may get an
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* exception between the new %fs descriptor being loaded and
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* %fs being effectively cleared at __switch_to().
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*/
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if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) {
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#ifdef CONFIG_X86_32
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lazy_load_gs(0);
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#else
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loadsegment(fs, 0);
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#endif
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}
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xen_mc_batch();
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load_TLS_descriptor(t, cpu, 0);
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load_TLS_descriptor(t, cpu, 1);
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load_TLS_descriptor(t, cpu, 2);
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xen_mc_issue(PARAVIRT_LAZY_CPU);
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}
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#ifdef CONFIG_X86_64
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static void xen_load_gs_index(unsigned int idx)
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{
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if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx))
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BUG();
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}
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#endif
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static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
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const void *ptr)
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{
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xmaddr_t mach_lp = arbitrary_virt_to_machine(&dt[entrynum]);
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u64 entry = *(u64 *)ptr;
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preempt_disable();
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xen_mc_flush();
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if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
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BUG();
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preempt_enable();
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}
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static int cvt_gate_to_trap(int vector, const gate_desc *val,
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struct trap_info *info)
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{
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if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT)
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return 0;
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info->vector = vector;
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info->address = gate_offset(*val);
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info->cs = gate_segment(*val);
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info->flags = val->dpl;
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/* interrupt gates clear IF */
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if (val->type == GATE_INTERRUPT)
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info->flags |= 1 << 2;
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return 1;
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}
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/* Locations of each CPU's IDT */
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static DEFINE_PER_CPU(struct desc_ptr, idt_desc);
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/* Set an IDT entry. If the entry is part of the current IDT, then
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also update Xen. */
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static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g)
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{
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unsigned long p = (unsigned long)&dt[entrynum];
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unsigned long start, end;
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preempt_disable();
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start = __get_cpu_var(idt_desc).address;
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end = start + __get_cpu_var(idt_desc).size + 1;
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xen_mc_flush();
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native_write_idt_entry(dt, entrynum, g);
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if (p >= start && (p + 8) <= end) {
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struct trap_info info[2];
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info[1].address = 0;
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if (cvt_gate_to_trap(entrynum, g, &info[0]))
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if (HYPERVISOR_set_trap_table(info))
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BUG();
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}
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preempt_enable();
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}
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static void xen_convert_trap_info(const struct desc_ptr *desc,
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struct trap_info *traps)
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{
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unsigned in, out, count;
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count = (desc->size+1) / sizeof(gate_desc);
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BUG_ON(count > 256);
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for (in = out = 0; in < count; in++) {
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gate_desc *entry = (gate_desc*)(desc->address) + in;
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if (cvt_gate_to_trap(in, entry, &traps[out]))
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out++;
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}
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traps[out].address = 0;
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}
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void xen_copy_trap_info(struct trap_info *traps)
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{
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const struct desc_ptr *desc = &__get_cpu_var(idt_desc);
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xen_convert_trap_info(desc, traps);
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}
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/* Load a new IDT into Xen. In principle this can be per-CPU, so we
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hold a spinlock to protect the static traps[] array (static because
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it avoids allocation, and saves stack space). */
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static void xen_load_idt(const struct desc_ptr *desc)
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{
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static DEFINE_SPINLOCK(lock);
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static struct trap_info traps[257];
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spin_lock(&lock);
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__get_cpu_var(idt_desc) = *desc;
|
|
|
|
xen_convert_trap_info(desc, traps);
|
|
|
|
xen_mc_flush();
|
|
if (HYPERVISOR_set_trap_table(traps))
|
|
BUG();
|
|
|
|
spin_unlock(&lock);
|
|
}
|
|
|
|
/* Write a GDT descriptor entry. Ignore LDT descriptors, since
|
|
they're handled differently. */
|
|
static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
|
|
const void *desc, int type)
|
|
{
|
|
preempt_disable();
|
|
|
|
switch (type) {
|
|
case DESC_LDT:
|
|
case DESC_TSS:
|
|
/* ignore */
|
|
break;
|
|
|
|
default: {
|
|
xmaddr_t maddr = arbitrary_virt_to_machine(&dt[entry]);
|
|
|
|
xen_mc_flush();
|
|
if (HYPERVISOR_update_descriptor(maddr.maddr, *(u64 *)desc))
|
|
BUG();
|
|
}
|
|
|
|
}
|
|
|
|
preempt_enable();
|
|
}
|
|
|
|
static void xen_load_sp0(struct tss_struct *tss,
|
|
struct thread_struct *thread)
|
|
{
|
|
struct multicall_space mcs = xen_mc_entry(0);
|
|
MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
|
|
xen_mc_issue(PARAVIRT_LAZY_CPU);
|
|
}
|
|
|
|
static void xen_set_iopl_mask(unsigned mask)
|
|
{
|
|
struct physdev_set_iopl set_iopl;
|
|
|
|
/* Force the change at ring 0. */
|
|
set_iopl.iopl = (mask == 0) ? 1 : (mask >> 12) & 3;
|
|
HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
|
|
}
|
|
|
|
static void xen_io_delay(void)
|
|
{
|
|
}
|
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
static u32 xen_apic_read(u32 reg)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void xen_apic_write(u32 reg, u32 val)
|
|
{
|
|
/* Warn to see if there's any stray references */
|
|
WARN_ON(1);
|
|
}
|
|
|
|
static u64 xen_apic_icr_read(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void xen_apic_icr_write(u32 low, u32 id)
|
|
{
|
|
/* Warn to see if there's any stray references */
|
|
WARN_ON(1);
|
|
}
|
|
|
|
static void xen_apic_wait_icr_idle(void)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static u32 xen_safe_apic_wait_icr_idle(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void set_xen_basic_apic_ops(void)
|
|
{
|
|
apic->read = xen_apic_read;
|
|
apic->write = xen_apic_write;
|
|
apic->icr_read = xen_apic_icr_read;
|
|
apic->icr_write = xen_apic_icr_write;
|
|
apic->wait_icr_idle = xen_apic_wait_icr_idle;
|
|
apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
static void xen_clts(void)
|
|
{
|
|
struct multicall_space mcs;
|
|
|
|
mcs = xen_mc_entry(0);
|
|
|
|
MULTI_fpu_taskswitch(mcs.mc, 0);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_CPU);
|
|
}
|
|
|
|
static void xen_write_cr0(unsigned long cr0)
|
|
{
|
|
struct multicall_space mcs;
|
|
|
|
/* Only pay attention to cr0.TS; everything else is
|
|
ignored. */
|
|
mcs = xen_mc_entry(0);
|
|
|
|
MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
|
|
|
|
xen_mc_issue(PARAVIRT_LAZY_CPU);
|
|
}
|
|
|
|
static void xen_write_cr4(unsigned long cr4)
|
|
{
|
|
cr4 &= ~X86_CR4_PGE;
|
|
cr4 &= ~X86_CR4_PSE;
|
|
|
|
native_write_cr4(cr4);
|
|
}
|
|
|
|
static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
|
|
{
|
|
int ret;
|
|
|
|
ret = 0;
|
|
|
|
switch (msr) {
|
|
#ifdef CONFIG_X86_64
|
|
unsigned which;
|
|
u64 base;
|
|
|
|
case MSR_FS_BASE: which = SEGBASE_FS; goto set;
|
|
case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set;
|
|
case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set;
|
|
|
|
set:
|
|
base = ((u64)high << 32) | low;
|
|
if (HYPERVISOR_set_segment_base(which, base) != 0)
|
|
ret = -EFAULT;
|
|
break;
|
|
#endif
|
|
|
|
case MSR_STAR:
|
|
case MSR_CSTAR:
|
|
case MSR_LSTAR:
|
|
case MSR_SYSCALL_MASK:
|
|
case MSR_IA32_SYSENTER_CS:
|
|
case MSR_IA32_SYSENTER_ESP:
|
|
case MSR_IA32_SYSENTER_EIP:
|
|
/* Fast syscall setup is all done in hypercalls, so
|
|
these are all ignored. Stub them out here to stop
|
|
Xen console noise. */
|
|
break;
|
|
|
|
default:
|
|
ret = native_write_msr_safe(msr, low, high);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
void xen_setup_shared_info(void)
|
|
{
|
|
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
|
|
set_fixmap(FIX_PARAVIRT_BOOTMAP,
|
|
xen_start_info->shared_info);
|
|
|
|
HYPERVISOR_shared_info =
|
|
(struct shared_info *)fix_to_virt(FIX_PARAVIRT_BOOTMAP);
|
|
} else
|
|
HYPERVISOR_shared_info =
|
|
(struct shared_info *)__va(xen_start_info->shared_info);
|
|
|
|
#ifndef CONFIG_SMP
|
|
/* In UP this is as good a place as any to set up shared info */
|
|
xen_setup_vcpu_info_placement();
|
|
#endif
|
|
|
|
xen_setup_mfn_list_list();
|
|
}
|
|
|
|
/* This is called once we have the cpu_possible_map */
|
|
void xen_setup_vcpu_info_placement(void)
|
|
{
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu)
|
|
xen_vcpu_setup(cpu);
|
|
|
|
/* xen_vcpu_setup managed to place the vcpu_info within the
|
|
percpu area for all cpus, so make use of it */
|
|
if (have_vcpu_info_placement) {
|
|
printk(KERN_INFO "Xen: using vcpu_info placement\n");
|
|
|
|
pv_irq_ops.save_fl = __PV_IS_CALLEE_SAVE(xen_save_fl_direct);
|
|
pv_irq_ops.restore_fl = __PV_IS_CALLEE_SAVE(xen_restore_fl_direct);
|
|
pv_irq_ops.irq_disable = __PV_IS_CALLEE_SAVE(xen_irq_disable_direct);
|
|
pv_irq_ops.irq_enable = __PV_IS_CALLEE_SAVE(xen_irq_enable_direct);
|
|
pv_mmu_ops.read_cr2 = xen_read_cr2_direct;
|
|
}
|
|
}
|
|
|
|
static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
|
|
unsigned long addr, unsigned len)
|
|
{
|
|
char *start, *end, *reloc;
|
|
unsigned ret;
|
|
|
|
start = end = reloc = NULL;
|
|
|
|
#define SITE(op, x) \
|
|
case PARAVIRT_PATCH(op.x): \
|
|
if (have_vcpu_info_placement) { \
|
|
start = (char *)xen_##x##_direct; \
|
|
end = xen_##x##_direct_end; \
|
|
reloc = xen_##x##_direct_reloc; \
|
|
} \
|
|
goto patch_site
|
|
|
|
switch (type) {
|
|
SITE(pv_irq_ops, irq_enable);
|
|
SITE(pv_irq_ops, irq_disable);
|
|
SITE(pv_irq_ops, save_fl);
|
|
SITE(pv_irq_ops, restore_fl);
|
|
#undef SITE
|
|
|
|
patch_site:
|
|
if (start == NULL || (end-start) > len)
|
|
goto default_patch;
|
|
|
|
ret = paravirt_patch_insns(insnbuf, len, start, end);
|
|
|
|
/* Note: because reloc is assigned from something that
|
|
appears to be an array, gcc assumes it's non-null,
|
|
but doesn't know its relationship with start and
|
|
end. */
|
|
if (reloc > start && reloc < end) {
|
|
int reloc_off = reloc - start;
|
|
long *relocp = (long *)(insnbuf + reloc_off);
|
|
long delta = start - (char *)addr;
|
|
|
|
*relocp += delta;
|
|
}
|
|
break;
|
|
|
|
default_patch:
|
|
default:
|
|
ret = paravirt_patch_default(type, clobbers, insnbuf,
|
|
addr, len);
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct pv_info xen_info __initdata = {
|
|
.paravirt_enabled = 1,
|
|
.shared_kernel_pmd = 0,
|
|
|
|
.name = "Xen",
|
|
};
|
|
|
|
static const struct pv_init_ops xen_init_ops __initdata = {
|
|
.patch = xen_patch,
|
|
|
|
.banner = xen_banner,
|
|
.memory_setup = xen_memory_setup,
|
|
.arch_setup = xen_arch_setup,
|
|
.post_allocator_init = xen_post_allocator_init,
|
|
};
|
|
|
|
static const struct pv_time_ops xen_time_ops __initdata = {
|
|
.time_init = xen_time_init,
|
|
|
|
.set_wallclock = xen_set_wallclock,
|
|
.get_wallclock = xen_get_wallclock,
|
|
.get_tsc_khz = xen_tsc_khz,
|
|
.sched_clock = xen_sched_clock,
|
|
};
|
|
|
|
static const struct pv_cpu_ops xen_cpu_ops __initdata = {
|
|
.cpuid = xen_cpuid,
|
|
|
|
.set_debugreg = xen_set_debugreg,
|
|
.get_debugreg = xen_get_debugreg,
|
|
|
|
.clts = xen_clts,
|
|
|
|
.read_cr0 = native_read_cr0,
|
|
.write_cr0 = xen_write_cr0,
|
|
|
|
.read_cr4 = native_read_cr4,
|
|
.read_cr4_safe = native_read_cr4_safe,
|
|
.write_cr4 = xen_write_cr4,
|
|
|
|
.wbinvd = native_wbinvd,
|
|
|
|
.read_msr = native_read_msr_safe,
|
|
.write_msr = xen_write_msr_safe,
|
|
.read_tsc = native_read_tsc,
|
|
.read_pmc = native_read_pmc,
|
|
|
|
.iret = xen_iret,
|
|
.irq_enable_sysexit = xen_sysexit,
|
|
#ifdef CONFIG_X86_64
|
|
.usergs_sysret32 = xen_sysret32,
|
|
.usergs_sysret64 = xen_sysret64,
|
|
#endif
|
|
|
|
.load_tr_desc = paravirt_nop,
|
|
.set_ldt = xen_set_ldt,
|
|
.load_gdt = xen_load_gdt,
|
|
.load_idt = xen_load_idt,
|
|
.load_tls = xen_load_tls,
|
|
#ifdef CONFIG_X86_64
|
|
.load_gs_index = xen_load_gs_index,
|
|
#endif
|
|
|
|
.alloc_ldt = xen_alloc_ldt,
|
|
.free_ldt = xen_free_ldt,
|
|
|
|
.store_gdt = native_store_gdt,
|
|
.store_idt = native_store_idt,
|
|
.store_tr = xen_store_tr,
|
|
|
|
.write_ldt_entry = xen_write_ldt_entry,
|
|
.write_gdt_entry = xen_write_gdt_entry,
|
|
.write_idt_entry = xen_write_idt_entry,
|
|
.load_sp0 = xen_load_sp0,
|
|
|
|
.set_iopl_mask = xen_set_iopl_mask,
|
|
.io_delay = xen_io_delay,
|
|
|
|
/* Xen takes care of %gs when switching to usermode for us */
|
|
.swapgs = paravirt_nop,
|
|
|
|
.lazy_mode = {
|
|
.enter = paravirt_enter_lazy_cpu,
|
|
.leave = xen_leave_lazy,
|
|
},
|
|
};
|
|
|
|
static const struct pv_apic_ops xen_apic_ops __initdata = {
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
.setup_boot_clock = paravirt_nop,
|
|
.setup_secondary_clock = paravirt_nop,
|
|
.startup_ipi_hook = paravirt_nop,
|
|
#endif
|
|
};
|
|
|
|
static void xen_reboot(int reason)
|
|
{
|
|
struct sched_shutdown r = { .reason = reason };
|
|
|
|
#ifdef CONFIG_SMP
|
|
smp_send_stop();
|
|
#endif
|
|
|
|
if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
|
|
BUG();
|
|
}
|
|
|
|
static void xen_restart(char *msg)
|
|
{
|
|
xen_reboot(SHUTDOWN_reboot);
|
|
}
|
|
|
|
static void xen_emergency_restart(void)
|
|
{
|
|
xen_reboot(SHUTDOWN_reboot);
|
|
}
|
|
|
|
static void xen_machine_halt(void)
|
|
{
|
|
xen_reboot(SHUTDOWN_poweroff);
|
|
}
|
|
|
|
static void xen_crash_shutdown(struct pt_regs *regs)
|
|
{
|
|
xen_reboot(SHUTDOWN_crash);
|
|
}
|
|
|
|
static const struct machine_ops __initdata xen_machine_ops = {
|
|
.restart = xen_restart,
|
|
.halt = xen_machine_halt,
|
|
.power_off = xen_machine_halt,
|
|
.shutdown = xen_machine_halt,
|
|
.crash_shutdown = xen_crash_shutdown,
|
|
.emergency_restart = xen_emergency_restart,
|
|
};
|
|
|
|
/* First C function to be called on Xen boot */
|
|
asmlinkage void __init xen_start_kernel(void)
|
|
{
|
|
pgd_t *pgd;
|
|
|
|
if (!xen_start_info)
|
|
return;
|
|
|
|
xen_domain_type = XEN_PV_DOMAIN;
|
|
|
|
BUG_ON(memcmp(xen_start_info->magic, "xen-3", 5) != 0);
|
|
|
|
xen_setup_features();
|
|
|
|
/* Install Xen paravirt ops */
|
|
pv_info = xen_info;
|
|
pv_init_ops = xen_init_ops;
|
|
pv_time_ops = xen_time_ops;
|
|
pv_cpu_ops = xen_cpu_ops;
|
|
pv_apic_ops = xen_apic_ops;
|
|
pv_mmu_ops = xen_mmu_ops;
|
|
|
|
xen_init_irq_ops();
|
|
|
|
xen_init_cpuid_mask();
|
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
/*
|
|
* set up the basic apic ops.
|
|
*/
|
|
set_xen_basic_apic_ops();
|
|
#endif
|
|
|
|
if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
|
|
pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start;
|
|
pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit;
|
|
}
|
|
|
|
machine_ops = xen_machine_ops;
|
|
|
|
#ifdef CONFIG_X86_64
|
|
/*
|
|
* Setup percpu state. We only need to do this for 64-bit
|
|
* because 32-bit already has %fs set properly.
|
|
*/
|
|
load_percpu_segment(0);
|
|
#endif
|
|
/*
|
|
* The only reliable way to retain the initial address of the
|
|
* percpu gdt_page is to remember it here, so we can go and
|
|
* mark it RW later, when the initial percpu area is freed.
|
|
*/
|
|
xen_initial_gdt = &per_cpu(gdt_page, 0);
|
|
|
|
xen_smp_init();
|
|
|
|
/* Get mfn list */
|
|
if (!xen_feature(XENFEAT_auto_translated_physmap))
|
|
xen_build_dynamic_phys_to_machine();
|
|
|
|
pgd = (pgd_t *)xen_start_info->pt_base;
|
|
|
|
/* Prevent unwanted bits from being set in PTEs. */
|
|
__supported_pte_mask &= ~_PAGE_GLOBAL;
|
|
if (!xen_initial_domain())
|
|
__supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
|
|
|
|
#ifdef CONFIG_X86_64
|
|
/* Work out if we support NX */
|
|
check_efer();
|
|
#endif
|
|
|
|
/* Don't do the full vcpu_info placement stuff until we have a
|
|
possible map and a non-dummy shared_info. */
|
|
per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
|
|
|
|
local_irq_disable();
|
|
early_boot_irqs_off();
|
|
|
|
xen_raw_console_write("mapping kernel into physical memory\n");
|
|
pgd = xen_setup_kernel_pagetable(pgd, xen_start_info->nr_pages);
|
|
|
|
init_mm.pgd = pgd;
|
|
|
|
/* keep using Xen gdt for now; no urgent need to change it */
|
|
|
|
pv_info.kernel_rpl = 1;
|
|
if (xen_feature(XENFEAT_supervisor_mode_kernel))
|
|
pv_info.kernel_rpl = 0;
|
|
|
|
/* set the limit of our address space */
|
|
xen_reserve_top();
|
|
|
|
#ifdef CONFIG_X86_32
|
|
/* set up basic CPUID stuff */
|
|
cpu_detect(&new_cpu_data);
|
|
new_cpu_data.hard_math = 1;
|
|
new_cpu_data.x86_capability[0] = cpuid_edx(1);
|
|
#endif
|
|
|
|
/* Poke various useful things into boot_params */
|
|
boot_params.hdr.type_of_loader = (9 << 4) | 0;
|
|
boot_params.hdr.ramdisk_image = xen_start_info->mod_start
|
|
? __pa(xen_start_info->mod_start) : 0;
|
|
boot_params.hdr.ramdisk_size = xen_start_info->mod_len;
|
|
boot_params.hdr.cmd_line_ptr = __pa(xen_start_info->cmd_line);
|
|
|
|
if (!xen_initial_domain()) {
|
|
add_preferred_console("xenboot", 0, NULL);
|
|
add_preferred_console("tty", 0, NULL);
|
|
add_preferred_console("hvc", 0, NULL);
|
|
}
|
|
|
|
xen_raw_console_write("about to get started...\n");
|
|
|
|
/* Start the world */
|
|
#ifdef CONFIG_X86_32
|
|
i386_start_kernel();
|
|
#else
|
|
x86_64_start_reservations((char *)__pa_symbol(&boot_params));
|
|
#endif
|
|
}
|