| /* |
| * Core of Xen paravirt_ops implementation. |
| * |
| * This file contains the xen_paravirt_ops structure itself, and the |
| * implementations for: |
| * - privileged instructions |
| * - interrupt flags |
| * - segment operations |
| * - booting and setup |
| * |
| * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/smp.h> |
| #include <linux/preempt.h> |
| #include <linux/hardirq.h> |
| #include <linux/percpu.h> |
| #include <linux/delay.h> |
| #include <linux/start_kernel.h> |
| #include <linux/sched.h> |
| #include <linux/bootmem.h> |
| #include <linux/module.h> |
| #include <linux/mm.h> |
| #include <linux/page-flags.h> |
| #include <linux/highmem.h> |
| #include <linux/console.h> |
| |
| #include <xen/interface/xen.h> |
| #include <xen/interface/physdev.h> |
| #include <xen/interface/vcpu.h> |
| #include <xen/interface/sched.h> |
| #include <xen/features.h> |
| #include <xen/page.h> |
| #include <xen/hvc-console.h> |
| |
| #include <asm/paravirt.h> |
| #include <asm/page.h> |
| #include <asm/xen/hypercall.h> |
| #include <asm/xen/hypervisor.h> |
| #include <asm/fixmap.h> |
| #include <asm/processor.h> |
| #include <asm/msr-index.h> |
| #include <asm/setup.h> |
| #include <asm/desc.h> |
| #include <asm/pgtable.h> |
| #include <asm/tlbflush.h> |
| #include <asm/reboot.h> |
| |
| #include "xen-ops.h" |
| #include "mmu.h" |
| #include "multicalls.h" |
| |
| EXPORT_SYMBOL_GPL(hypercall_page); |
| |
| DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); |
| DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info); |
| |
| /* |
| * Identity map, in addition to plain kernel map. This needs to be |
| * large enough to allocate page table pages to allocate the rest. |
| * Each page can map 2MB. |
| */ |
| static pte_t level1_ident_pgt[PTRS_PER_PTE * 4] __page_aligned_bss; |
| |
| #ifdef CONFIG_X86_64 |
| /* l3 pud for userspace vsyscall mapping */ |
| static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss; |
| #endif /* CONFIG_X86_64 */ |
| |
| /* |
| * Note about cr3 (pagetable base) values: |
| * |
| * xen_cr3 contains the current logical cr3 value; it contains the |
| * last set cr3. This may not be the current effective cr3, because |
| * its update may be being lazily deferred. However, a vcpu looking |
| * at its own cr3 can use this value knowing that it everything will |
| * be self-consistent. |
| * |
| * xen_current_cr3 contains the actual vcpu cr3; it is set once the |
| * hypercall to set the vcpu cr3 is complete (so it may be a little |
| * out of date, but it will never be set early). If one vcpu is |
| * looking at another vcpu's cr3 value, it should use this variable. |
| */ |
| DEFINE_PER_CPU(unsigned long, xen_cr3); /* cr3 stored as physaddr */ |
| DEFINE_PER_CPU(unsigned long, xen_current_cr3); /* actual vcpu cr3 */ |
| |
| struct start_info *xen_start_info; |
| EXPORT_SYMBOL_GPL(xen_start_info); |
| |
| struct shared_info xen_dummy_shared_info; |
| |
| /* |
| * Point at some empty memory to start with. We map the real shared_info |
| * page as soon as fixmap is up and running. |
| */ |
| struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; |
| |
| /* |
| * Flag to determine whether vcpu info placement is available on all |
| * VCPUs. We assume it is to start with, and then set it to zero on |
| * the first failure. This is because it can succeed on some VCPUs |
| * and not others, since it can involve hypervisor memory allocation, |
| * or because the guest failed to guarantee all the appropriate |
| * constraints on all VCPUs (ie buffer can't cross a page boundary). |
| * |
| * Note that any particular CPU may be using a placed vcpu structure, |
| * but we can only optimise if the all are. |
| * |
| * 0: not available, 1: available |
| */ |
| static int have_vcpu_info_placement = 1; |
| |
| static void xen_vcpu_setup(int cpu) |
| { |
| struct vcpu_register_vcpu_info info; |
| int err; |
| struct vcpu_info *vcpup; |
| |
| BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info); |
| per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu]; |
| |
| if (!have_vcpu_info_placement) |
| return; /* already tested, not available */ |
| |
| vcpup = &per_cpu(xen_vcpu_info, cpu); |
| |
| info.mfn = virt_to_mfn(vcpup); |
| info.offset = offset_in_page(vcpup); |
| |
| printk(KERN_DEBUG "trying to map vcpu_info %d at %p, mfn %llx, offset %d\n", |
| cpu, vcpup, info.mfn, info.offset); |
| |
| /* Check to see if the hypervisor will put the vcpu_info |
| structure where we want it, which allows direct access via |
| a percpu-variable. */ |
| err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info); |
| |
| if (err) { |
| printk(KERN_DEBUG "register_vcpu_info failed: err=%d\n", err); |
| have_vcpu_info_placement = 0; |
| } else { |
| /* This cpu is using the registered vcpu info, even if |
| later ones fail to. */ |
| per_cpu(xen_vcpu, cpu) = vcpup; |
| |
| printk(KERN_DEBUG "cpu %d using vcpu_info at %p\n", |
| cpu, vcpup); |
| } |
| } |
| |
| /* |
| * On restore, set the vcpu placement up again. |
| * If it fails, then we're in a bad state, since |
| * we can't back out from using it... |
| */ |
| void xen_vcpu_restore(void) |
| { |
| if (have_vcpu_info_placement) { |
| int cpu; |
| |
| for_each_online_cpu(cpu) { |
| bool other_cpu = (cpu != smp_processor_id()); |
| |
| if (other_cpu && |
| HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL)) |
| BUG(); |
| |
| xen_vcpu_setup(cpu); |
| |
| if (other_cpu && |
| HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL)) |
| BUG(); |
| } |
| |
| BUG_ON(!have_vcpu_info_placement); |
| } |
| } |
| |
| static void __init xen_banner(void) |
| { |
| unsigned version = HYPERVISOR_xen_version(XENVER_version, NULL); |
| struct xen_extraversion extra; |
| HYPERVISOR_xen_version(XENVER_extraversion, &extra); |
| |
| printk(KERN_INFO "Booting paravirtualized kernel on %s\n", |
| pv_info.name); |
| printk(KERN_INFO "Xen version: %d.%d%s%s\n", |
| version >> 16, version & 0xffff, extra.extraversion, |
| xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); |
| } |
| |
| static void xen_cpuid(unsigned int *ax, unsigned int *bx, |
| unsigned int *cx, unsigned int *dx) |
| { |
| unsigned maskedx = ~0; |
| |
| /* |
| * Mask out inconvenient features, to try and disable as many |
| * unsupported kernel subsystems as possible. |
| */ |
| if (*ax == 1) |
| maskedx = ~((1 << X86_FEATURE_APIC) | /* disable APIC */ |
| (1 << X86_FEATURE_ACPI) | /* disable ACPI */ |
| (1 << X86_FEATURE_MCE) | /* disable MCE */ |
| (1 << X86_FEATURE_MCA) | /* disable MCA */ |
| (1 << X86_FEATURE_ACC)); /* thermal monitoring */ |
| |
| asm(XEN_EMULATE_PREFIX "cpuid" |
| : "=a" (*ax), |
| "=b" (*bx), |
| "=c" (*cx), |
| "=d" (*dx) |
| : "0" (*ax), "2" (*cx)); |
| *dx &= maskedx; |
| } |
| |
| static void xen_set_debugreg(int reg, unsigned long val) |
| { |
| HYPERVISOR_set_debugreg(reg, val); |
| } |
| |
| static unsigned long xen_get_debugreg(int reg) |
| { |
| return HYPERVISOR_get_debugreg(reg); |
| } |
| |
| static unsigned long xen_save_fl(void) |
| { |
| struct vcpu_info *vcpu; |
| unsigned long flags; |
| |
| vcpu = x86_read_percpu(xen_vcpu); |
| |
| /* flag has opposite sense of mask */ |
| flags = !vcpu->evtchn_upcall_mask; |
| |
| /* convert to IF type flag |
| -0 -> 0x00000000 |
| -1 -> 0xffffffff |
| */ |
| return (-flags) & X86_EFLAGS_IF; |
| } |
| |
| static void xen_restore_fl(unsigned long flags) |
| { |
| struct vcpu_info *vcpu; |
| |
| /* convert from IF type flag */ |
| flags = !(flags & X86_EFLAGS_IF); |
| |
| /* There's a one instruction preempt window here. We need to |
| make sure we're don't switch CPUs between getting the vcpu |
| pointer and updating the mask. */ |
| preempt_disable(); |
| vcpu = x86_read_percpu(xen_vcpu); |
| vcpu->evtchn_upcall_mask = flags; |
| preempt_enable_no_resched(); |
| |
| /* Doesn't matter if we get preempted here, because any |
| pending event will get dealt with anyway. */ |
| |
| if (flags == 0) { |
| preempt_check_resched(); |
| barrier(); /* unmask then check (avoid races) */ |
| if (unlikely(vcpu->evtchn_upcall_pending)) |
| force_evtchn_callback(); |
| } |
| } |
| |
| static void xen_irq_disable(void) |
| { |
| /* There's a one instruction preempt window here. We need to |
| make sure we're don't switch CPUs between getting the vcpu |
| pointer and updating the mask. */ |
| preempt_disable(); |
| x86_read_percpu(xen_vcpu)->evtchn_upcall_mask = 1; |
| preempt_enable_no_resched(); |
| } |
| |
| static void xen_irq_enable(void) |
| { |
| struct vcpu_info *vcpu; |
| |
| /* We don't need to worry about being preempted here, since |
| either a) interrupts are disabled, so no preemption, or b) |
| the caller is confused and is trying to re-enable interrupts |
| on an indeterminate processor. */ |
| |
| vcpu = x86_read_percpu(xen_vcpu); |
| vcpu->evtchn_upcall_mask = 0; |
| |
| /* Doesn't matter if we get preempted here, because any |
| pending event will get dealt with anyway. */ |
| |
| barrier(); /* unmask then check (avoid races) */ |
| if (unlikely(vcpu->evtchn_upcall_pending)) |
| force_evtchn_callback(); |
| } |
| |
| static void xen_safe_halt(void) |
| { |
| /* Blocking includes an implicit local_irq_enable(). */ |
| if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0) |
| BUG(); |
| } |
| |
| static void xen_halt(void) |
| { |
| if (irqs_disabled()) |
| HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL); |
| else |
| xen_safe_halt(); |
| } |
| |
| static void xen_leave_lazy(void) |
| { |
| paravirt_leave_lazy(paravirt_get_lazy_mode()); |
| xen_mc_flush(); |
| } |
| |
| static unsigned long xen_store_tr(void) |
| { |
| return 0; |
| } |
| |
| static void xen_set_ldt(const void *addr, unsigned entries) |
| { |
| struct mmuext_op *op; |
| struct multicall_space mcs = xen_mc_entry(sizeof(*op)); |
| |
| op = mcs.args; |
| op->cmd = MMUEXT_SET_LDT; |
| op->arg1.linear_addr = (unsigned long)addr; |
| op->arg2.nr_ents = entries; |
| |
| MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); |
| |
| xen_mc_issue(PARAVIRT_LAZY_CPU); |
| } |
| |
| static void xen_load_gdt(const struct desc_ptr *dtr) |
| { |
| unsigned long *frames; |
| unsigned long va = dtr->address; |
| unsigned int size = dtr->size + 1; |
| unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE; |
| int f; |
| struct multicall_space mcs; |
| |
| /* A GDT can be up to 64k in size, which corresponds to 8192 |
| 8-byte entries, or 16 4k pages.. */ |
| |
| BUG_ON(size > 65536); |
| BUG_ON(va & ~PAGE_MASK); |
| |
| mcs = xen_mc_entry(sizeof(*frames) * pages); |
| frames = mcs.args; |
| |
| for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { |
| frames[f] = virt_to_mfn(va); |
| make_lowmem_page_readonly((void *)va); |
| } |
| |
| MULTI_set_gdt(mcs.mc, frames, size / sizeof(struct desc_struct)); |
| |
| xen_mc_issue(PARAVIRT_LAZY_CPU); |
| } |
| |
| static void load_TLS_descriptor(struct thread_struct *t, |
| unsigned int cpu, unsigned int i) |
| { |
| struct desc_struct *gdt = get_cpu_gdt_table(cpu); |
| xmaddr_t maddr = virt_to_machine(&gdt[GDT_ENTRY_TLS_MIN+i]); |
| struct multicall_space mc = __xen_mc_entry(0); |
| |
| MULTI_update_descriptor(mc.mc, maddr.maddr, t->tls_array[i]); |
| } |
| |
| static void xen_load_tls(struct thread_struct *t, unsigned int cpu) |
| { |
| /* |
| * XXX sleazy hack: If we're being called in a lazy-cpu zone, |
| * it means we're in a context switch, and %gs has just been |
| * saved. This means we can zero it out to prevent faults on |
| * exit from the hypervisor if the next process has no %gs. |
| * Either way, it has been saved, and the new value will get |
| * loaded properly. This will go away as soon as Xen has been |
| * modified to not save/restore %gs for normal hypercalls. |
| * |
| * On x86_64, this hack is not used for %gs, because gs points |
| * to KERNEL_GS_BASE (and uses it for PDA references), so we |
| * must not zero %gs on x86_64 |
| * |
| * For x86_64, we need to zero %fs, otherwise we may get an |
| * exception between the new %fs descriptor being loaded and |
| * %fs being effectively cleared at __switch_to(). |
| */ |
| if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { |
| #ifdef CONFIG_X86_32 |
| loadsegment(gs, 0); |
| #else |
| loadsegment(fs, 0); |
| #endif |
| } |
| |
| xen_mc_batch(); |
| |
| load_TLS_descriptor(t, cpu, 0); |
| load_TLS_descriptor(t, cpu, 1); |
| load_TLS_descriptor(t, cpu, 2); |
| |
| xen_mc_issue(PARAVIRT_LAZY_CPU); |
| } |
| |
| #ifdef CONFIG_X86_64 |
| static void xen_load_gs_index(unsigned int idx) |
| { |
| if (HYPERVISOR_set_segment_base(SEGBASE_GS_USER_SEL, idx)) |
| BUG(); |
| } |
| #endif |
| |
| static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, |
| const void *ptr) |
| { |
| unsigned long lp = (unsigned long)&dt[entrynum]; |
| xmaddr_t mach_lp = virt_to_machine(lp); |
| u64 entry = *(u64 *)ptr; |
| |
| preempt_disable(); |
| |
| xen_mc_flush(); |
| if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry)) |
| BUG(); |
| |
| preempt_enable(); |
| } |
| |
| static int cvt_gate_to_trap(int vector, const gate_desc *val, |
| struct trap_info *info) |
| { |
| if (val->type != 0xf && val->type != 0xe) |
| return 0; |
| |
| info->vector = vector; |
| info->address = gate_offset(*val); |
| info->cs = gate_segment(*val); |
| info->flags = val->dpl; |
| /* interrupt gates clear IF */ |
| if (val->type == 0xe) |
| info->flags |= 4; |
| |
| return 1; |
| } |
| |
| /* Locations of each CPU's IDT */ |
| static DEFINE_PER_CPU(struct desc_ptr, idt_desc); |
| |
| /* Set an IDT entry. If the entry is part of the current IDT, then |
| also update Xen. */ |
| static void xen_write_idt_entry(gate_desc *dt, int entrynum, const gate_desc *g) |
| { |
| unsigned long p = (unsigned long)&dt[entrynum]; |
| unsigned long start, end; |
| |
| preempt_disable(); |
| |
| start = __get_cpu_var(idt_desc).address; |
| end = start + __get_cpu_var(idt_desc).size + 1; |
| |
| xen_mc_flush(); |
| |
| native_write_idt_entry(dt, entrynum, g); |
| |
| if (p >= start && (p + 8) <= end) { |
| struct trap_info info[2]; |
| |
| info[1].address = 0; |
| |
| if (cvt_gate_to_trap(entrynum, g, &info[0])) |
| if (HYPERVISOR_set_trap_table(info)) |
| BUG(); |
| } |
| |
| preempt_enable(); |
| } |
| |
| static void xen_convert_trap_info(const struct desc_ptr *desc, |
| struct trap_info *traps) |
| { |
| unsigned in, out, count; |
| |
| count = (desc->size+1) / sizeof(gate_desc); |
| BUG_ON(count > 256); |
| |
| for (in = out = 0; in < count; in++) { |
| gate_desc *entry = (gate_desc*)(desc->address) + in; |
| |
| if (cvt_gate_to_trap(in, entry, &traps[out])) |
| out++; |
| } |
| traps[out].address = 0; |
| } |
| |
| void xen_copy_trap_info(struct trap_info *traps) |
| { |
| const struct desc_ptr *desc = &__get_cpu_var(idt_desc); |
| |
| xen_convert_trap_info(desc, traps); |
| } |
| |
| /* Load a new IDT into Xen. In principle this can be per-CPU, so we |
| hold a spinlock to protect the static traps[] array (static because |
| it avoids allocation, and saves stack space). */ |
| static void xen_load_idt(const struct desc_ptr *desc) |
| { |
| static DEFINE_SPINLOCK(lock); |
| static struct trap_info traps[257]; |
| |
| spin_lock(&lock); |
| |
| __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 = 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(unsigned long reg) |
| { |
| return 0; |
| } |
| |
| static void xen_apic_write(unsigned long reg, u32 val) |
| { |
| /* Warn to see if there's any stray references */ |
| WARN_ON(1); |
| } |
| #endif |
| |
| static void xen_flush_tlb(void) |
| { |
| struct mmuext_op *op; |
| struct multicall_space mcs; |
| |
| preempt_disable(); |
| |
| mcs = xen_mc_entry(sizeof(*op)); |
| |
| op = mcs.args; |
| op->cmd = MMUEXT_TLB_FLUSH_LOCAL; |
| MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); |
| |
| xen_mc_issue(PARAVIRT_LAZY_MMU); |
| |
| preempt_enable(); |
| } |
| |
| static void xen_flush_tlb_single(unsigned long addr) |
| { |
| struct mmuext_op *op; |
| struct multicall_space mcs; |
| |
| preempt_disable(); |
| |
| mcs = xen_mc_entry(sizeof(*op)); |
| op = mcs.args; |
| op->cmd = MMUEXT_INVLPG_LOCAL; |
| op->arg1.linear_addr = addr & PAGE_MASK; |
| MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); |
| |
| xen_mc_issue(PARAVIRT_LAZY_MMU); |
| |
| preempt_enable(); |
| } |
| |
| static void xen_flush_tlb_others(const cpumask_t *cpus, struct mm_struct *mm, |
| unsigned long va) |
| { |
| struct { |
| struct mmuext_op op; |
| cpumask_t mask; |
| } *args; |
| cpumask_t cpumask = *cpus; |
| struct multicall_space mcs; |
| |
| /* |
| * A couple of (to be removed) sanity checks: |
| * |
| * - current CPU must not be in mask |
| * - mask must exist :) |
| */ |
| BUG_ON(cpus_empty(cpumask)); |
| BUG_ON(cpu_isset(smp_processor_id(), cpumask)); |
| BUG_ON(!mm); |
| |
| /* If a CPU which we ran on has gone down, OK. */ |
| cpus_and(cpumask, cpumask, cpu_online_map); |
| if (cpus_empty(cpumask)) |
| return; |
| |
| mcs = xen_mc_entry(sizeof(*args)); |
| args = mcs.args; |
| args->mask = cpumask; |
| args->op.arg2.vcpumask = &args->mask; |
| |
| if (va == TLB_FLUSH_ALL) { |
| args->op.cmd = MMUEXT_TLB_FLUSH_MULTI; |
| } else { |
| args->op.cmd = MMUEXT_INVLPG_MULTI; |
| args->op.arg1.linear_addr = va; |
| } |
| |
| MULTI_mmuext_op(mcs.mc, &args->op, 1, NULL, DOMID_SELF); |
| |
| xen_mc_issue(PARAVIRT_LAZY_MMU); |
| } |
| |
| 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_cr2(unsigned long cr2) |
| { |
| x86_read_percpu(xen_vcpu)->arch.cr2 = cr2; |
| } |
| |
| static unsigned long xen_read_cr2(void) |
| { |
| return x86_read_percpu(xen_vcpu)->arch.cr2; |
| } |
| |
| static unsigned long xen_read_cr2_direct(void) |
| { |
| return x86_read_percpu(xen_vcpu_info.arch.cr2); |
| } |
| |
| static void xen_write_cr4(unsigned long cr4) |
| { |
| cr4 &= ~X86_CR4_PGE; |
| cr4 &= ~X86_CR4_PSE; |
| |
| native_write_cr4(cr4); |
| } |
| |
| static unsigned long xen_read_cr3(void) |
| { |
| return x86_read_percpu(xen_cr3); |
| } |
| |
| static void set_current_cr3(void *v) |
| { |
| x86_write_percpu(xen_current_cr3, (unsigned long)v); |
| } |
| |
| static void __xen_write_cr3(bool kernel, unsigned long cr3) |
| { |
| struct mmuext_op *op; |
| struct multicall_space mcs; |
| unsigned long mfn; |
| |
| if (cr3) |
| mfn = pfn_to_mfn(PFN_DOWN(cr3)); |
| else |
| mfn = 0; |
| |
| WARN_ON(mfn == 0 && kernel); |
| |
| mcs = __xen_mc_entry(sizeof(*op)); |
| |
| op = mcs.args; |
| op->cmd = kernel ? MMUEXT_NEW_BASEPTR : MMUEXT_NEW_USER_BASEPTR; |
| op->arg1.mfn = mfn; |
| |
| MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); |
| |
| if (kernel) { |
| x86_write_percpu(xen_cr3, cr3); |
| |
| /* Update xen_current_cr3 once the batch has actually |
| been submitted. */ |
| xen_mc_callback(set_current_cr3, (void *)cr3); |
| } |
| } |
| |
| static void xen_write_cr3(unsigned long cr3) |
| { |
| BUG_ON(preemptible()); |
| |
| xen_mc_batch(); /* disables interrupts */ |
| |
| /* Update while interrupts are disabled, so its atomic with |
| respect to ipis */ |
| x86_write_percpu(xen_cr3, cr3); |
| |
| __xen_write_cr3(true, cr3); |
| |
| #ifdef CONFIG_X86_64 |
| { |
| pgd_t *user_pgd = xen_get_user_pgd(__va(cr3)); |
| if (user_pgd) |
| __xen_write_cr3(false, __pa(user_pgd)); |
| else |
| __xen_write_cr3(false, 0); |
| } |
| #endif |
| |
| xen_mc_issue(PARAVIRT_LAZY_CPU); /* interrupts restored */ |
| } |
| |
| 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 |
| default: |
| ret = native_write_msr_safe(msr, low, high); |
| } |
| |
| return ret; |
| } |
| |
| /* Early in boot, while setting up the initial pagetable, assume |
| everything is pinned. */ |
| static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn) |
| { |
| #ifdef CONFIG_FLATMEM |
| BUG_ON(mem_map); /* should only be used early */ |
| #endif |
| make_lowmem_page_readonly(__va(PFN_PHYS(pfn))); |
| } |
| |
| /* Early release_pte assumes that all pts are pinned, since there's |
| only init_mm and anything attached to that is pinned. */ |
| static void xen_release_pte_init(unsigned long pfn) |
| { |
| make_lowmem_page_readwrite(__va(PFN_PHYS(pfn))); |
| } |
| |
| static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn) |
| { |
| struct mmuext_op op; |
| op.cmd = cmd; |
| op.arg1.mfn = pfn_to_mfn(pfn); |
| if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF)) |
| BUG(); |
| } |
| |
| /* This needs to make sure the new pte page is pinned iff its being |
| attached to a pinned pagetable. */ |
| static void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned level) |
| { |
| struct page *page = pfn_to_page(pfn); |
| |
| if (PagePinned(virt_to_page(mm->pgd))) { |
| SetPagePinned(page); |
| |
| if (!PageHighMem(page)) { |
| make_lowmem_page_readonly(__va(PFN_PHYS(pfn))); |
| if (level == PT_PTE) |
| pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn); |
| } else |
| /* make sure there are no stray mappings of |
| this page */ |
| kmap_flush_unused(); |
| } |
| } |
| |
| static void xen_alloc_pte(struct mm_struct *mm, unsigned long pfn) |
| { |
| xen_alloc_ptpage(mm, pfn, PT_PTE); |
| } |
| |
| static void xen_alloc_pmd(struct mm_struct *mm, unsigned long pfn) |
| { |
| xen_alloc_ptpage(mm, pfn, PT_PMD); |
| } |
| |
| static int xen_pgd_alloc(struct mm_struct *mm) |
| { |
| pgd_t *pgd = mm->pgd; |
| int ret = 0; |
| |
| BUG_ON(PagePinned(virt_to_page(pgd))); |
| |
| #ifdef CONFIG_X86_64 |
| { |
| struct page *page = virt_to_page(pgd); |
| pgd_t *user_pgd; |
| |
| BUG_ON(page->private != 0); |
| |
| ret = -ENOMEM; |
| |
| user_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); |
| page->private = (unsigned long)user_pgd; |
| |
| if (user_pgd != NULL) { |
| user_pgd[pgd_index(VSYSCALL_START)] = |
| __pgd(__pa(level3_user_vsyscall) | _PAGE_TABLE); |
| ret = 0; |
| } |
| |
| BUG_ON(PagePinned(virt_to_page(xen_get_user_pgd(pgd)))); |
| } |
| #endif |
| |
| return ret; |
| } |
| |
| static void xen_pgd_free(struct mm_struct *mm, pgd_t *pgd) |
| { |
| #ifdef CONFIG_X86_64 |
| pgd_t *user_pgd = xen_get_user_pgd(pgd); |
| |
| if (user_pgd) |
| free_page((unsigned long)user_pgd); |
| #endif |
| } |
| |
| /* This should never happen until we're OK to use struct page */ |
| static void xen_release_ptpage(unsigned long pfn, unsigned level) |
| { |
| struct page *page = pfn_to_page(pfn); |
| |
| if (PagePinned(page)) { |
| if (!PageHighMem(page)) { |
| if (level == PT_PTE) |
| pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn); |
| make_lowmem_page_readwrite(__va(PFN_PHYS(pfn))); |
| } |
| ClearPagePinned(page); |
| } |
| } |
| |
| static void xen_release_pte(unsigned long pfn) |
| { |
| xen_release_ptpage(pfn, PT_PTE); |
| } |
| |
| static void xen_release_pmd(unsigned long pfn) |
| { |
| xen_release_ptpage(pfn, PT_PMD); |
| } |
| |
| #if PAGETABLE_LEVELS == 4 |
| static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn) |
| { |
| xen_alloc_ptpage(mm, pfn, PT_PUD); |
| } |
| |
| static void xen_release_pud(unsigned long pfn) |
| { |
| xen_release_ptpage(pfn, PT_PUD); |
| } |
| #endif |
| |
| #ifdef CONFIG_HIGHPTE |
| static void *xen_kmap_atomic_pte(struct page *page, enum km_type type) |
| { |
| pgprot_t prot = PAGE_KERNEL; |
| |
| if (PagePinned(page)) |
| prot = PAGE_KERNEL_RO; |
| |
| if (0 && PageHighMem(page)) |
| printk("mapping highpte %lx type %d prot %s\n", |
| page_to_pfn(page), type, |
| (unsigned long)pgprot_val(prot) & _PAGE_RW ? "WRITE" : "READ"); |
| |
| return kmap_atomic_prot(page, type, prot); |
| } |
| #endif |
| |
| static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte) |
| { |
| /* If there's an existing pte, then don't allow _PAGE_RW to be set */ |
| if (pte_val_ma(*ptep) & _PAGE_PRESENT) |
| pte = __pte_ma(((pte_val_ma(*ptep) & _PAGE_RW) | ~_PAGE_RW) & |
| pte_val_ma(pte)); |
| |
| return pte; |
| } |
| |
| /* Init-time set_pte while constructing initial pagetables, which |
| doesn't allow RO pagetable pages to be remapped RW */ |
| static __init void xen_set_pte_init(pte_t *ptep, pte_t pte) |
| { |
| pte = mask_rw_pte(ptep, pte); |
| |
| xen_set_pte(ptep, pte); |
| } |
| |
| static __init void xen_pagetable_setup_start(pgd_t *base) |
| { |
| } |
| |
| 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(); |
| } |
| |
| static __init void xen_pagetable_setup_done(pgd_t *base) |
| { |
| xen_setup_shared_info(); |
| } |
| |
| static __init void xen_post_allocator_init(void) |
| { |
| pv_mmu_ops.set_pte = xen_set_pte; |
| pv_mmu_ops.set_pmd = xen_set_pmd; |
| pv_mmu_ops.set_pud = xen_set_pud; |
| #if PAGETABLE_LEVELS == 4 |
| pv_mmu_ops.set_pgd = xen_set_pgd; |
| #endif |
| |
| /* This will work as long as patching hasn't happened yet |
| (which it hasn't) */ |
| pv_mmu_ops.alloc_pte = xen_alloc_pte; |
| pv_mmu_ops.alloc_pmd = xen_alloc_pmd; |
| pv_mmu_ops.release_pte = xen_release_pte; |
| pv_mmu_ops.release_pmd = xen_release_pmd; |
| #if PAGETABLE_LEVELS == 4 |
| pv_mmu_ops.alloc_pud = xen_alloc_pud; |
| pv_mmu_ops.release_pud = xen_release_pud; |
| #endif |
| |
| #ifdef CONFIG_X86_64 |
| SetPagePinned(virt_to_page(level3_user_vsyscall)); |
| #endif |
| xen_mark_init_mm_pinned(); |
| } |
| |
| /* 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 */ |
| #ifdef CONFIG_X86_32 |
| if (have_vcpu_info_placement) { |
| printk(KERN_INFO "Xen: using vcpu_info placement\n"); |
| |
| pv_irq_ops.save_fl = xen_save_fl_direct; |
| pv_irq_ops.restore_fl = xen_restore_fl_direct; |
| pv_irq_ops.irq_disable = xen_irq_disable_direct; |
| pv_irq_ops.irq_enable = xen_irq_enable_direct; |
| pv_mmu_ops.read_cr2 = xen_read_cr2_direct; |
| } |
| #endif |
| } |
| |
| 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) { |
| #ifdef CONFIG_X86_32 |
| SITE(pv_irq_ops, irq_enable); |
| SITE(pv_irq_ops, irq_disable); |
| SITE(pv_irq_ops, save_fl); |
| SITE(pv_irq_ops, restore_fl); |
| #endif /* CONFIG_X86_32 */ |
| #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 void xen_set_fixmap(unsigned idx, unsigned long phys, pgprot_t prot) |
| { |
| pte_t pte; |
| |
| phys >>= PAGE_SHIFT; |
| |
| switch (idx) { |
| case FIX_BTMAP_END ... FIX_BTMAP_BEGIN: |
| #ifdef CONFIG_X86_F00F_BUG |
| case FIX_F00F_IDT: |
| #endif |
| #ifdef CONFIG_X86_32 |
| case FIX_WP_TEST: |
| case FIX_VDSO: |
| # ifdef CONFIG_HIGHMEM |
| case FIX_KMAP_BEGIN ... FIX_KMAP_END: |
| # endif |
| #else |
| case VSYSCALL_LAST_PAGE ... VSYSCALL_FIRST_PAGE: |
| #endif |
| #ifdef CONFIG_X86_LOCAL_APIC |
| case FIX_APIC_BASE: /* maps dummy local APIC */ |
| #endif |
| pte = pfn_pte(phys, prot); |
| break; |
| |
| default: |
| pte = mfn_pte(phys, prot); |
| break; |
| } |
| |
| __native_set_fixmap(idx, pte); |
| |
| #ifdef CONFIG_X86_64 |
| /* Replicate changes to map the vsyscall page into the user |
| pagetable vsyscall mapping. */ |
| if (idx >= VSYSCALL_LAST_PAGE && idx <= VSYSCALL_FIRST_PAGE) { |
| unsigned long vaddr = __fix_to_virt(idx); |
| set_pte_vaddr_pud(level3_user_vsyscall, vaddr, pte); |
| } |
| #endif |
| } |
| |
| 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 |
| |
| .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 void __init __xen_init_IRQ(void) |
| { |
| #ifdef CONFIG_X86_64 |
| int i; |
| |
| /* Create identity vector->irq map */ |
| for(i = 0; i < NR_VECTORS; i++) { |
| int cpu; |
| |
| for_each_possible_cpu(cpu) |
| per_cpu(vector_irq, cpu)[i] = i; |
| } |
| #endif /* CONFIG_X86_64 */ |
| |
| xen_init_IRQ(); |
| } |
| |
| static const struct pv_irq_ops xen_irq_ops __initdata = { |
| .init_IRQ = __xen_init_IRQ, |
| .save_fl = xen_save_fl, |
| .restore_fl = xen_restore_fl, |
| .irq_disable = xen_irq_disable, |
| .irq_enable = xen_irq_enable, |
| .safe_halt = xen_safe_halt, |
| .halt = xen_halt, |
| #ifdef CONFIG_X86_64 |
| .adjust_exception_frame = xen_adjust_exception_frame, |
| #endif |
| }; |
| |
| static const struct pv_apic_ops xen_apic_ops __initdata = { |
| #ifdef CONFIG_X86_LOCAL_APIC |
| .apic_write = xen_apic_write, |
| .apic_read = xen_apic_read, |
| .setup_boot_clock = paravirt_nop, |
| .setup_secondary_clock = paravirt_nop, |
| .startup_ipi_hook = paravirt_nop, |
| #endif |
| }; |
| |
| static const struct pv_mmu_ops xen_mmu_ops __initdata = { |
| .pagetable_setup_start = xen_pagetable_setup_start, |
| .pagetable_setup_done = xen_pagetable_setup_done, |
| |
| .read_cr2 = xen_read_cr2, |
| .write_cr2 = xen_write_cr2, |
| |
| .read_cr3 = xen_read_cr3, |
| .write_cr3 = xen_write_cr3, |
| |
| .flush_tlb_user = xen_flush_tlb, |
| .flush_tlb_kernel = xen_flush_tlb, |
| .flush_tlb_single = xen_flush_tlb_single, |
| .flush_tlb_others = xen_flush_tlb_others, |
| |
| .pte_update = paravirt_nop, |
| .pte_update_defer = paravirt_nop, |
| |
| .pgd_alloc = xen_pgd_alloc, |
| .pgd_free = xen_pgd_free, |
| |
| .alloc_pte = xen_alloc_pte_init, |
| .release_pte = xen_release_pte_init, |
| .alloc_pmd = xen_alloc_pte_init, |
| .alloc_pmd_clone = paravirt_nop, |
| .release_pmd = xen_release_pte_init, |
| |
| #ifdef CONFIG_HIGHPTE |
| .kmap_atomic_pte = xen_kmap_atomic_pte, |
| #endif |
| |
| #ifdef CONFIG_X86_64 |
| .set_pte = xen_set_pte, |
| #else |
| .set_pte = xen_set_pte_init, |
| #endif |
| .set_pte_at = xen_set_pte_at, |
| .set_pmd = xen_set_pmd_hyper, |
| |
| .ptep_modify_prot_start = __ptep_modify_prot_start, |
| .ptep_modify_prot_commit = __ptep_modify_prot_commit, |
| |
| .pte_val = xen_pte_val, |
| .pte_flags = native_pte_val, |
| .pgd_val = xen_pgd_val, |
| |
| .make_pte = xen_make_pte, |
| .make_pgd = xen_make_pgd, |
| |
| #ifdef CONFIG_X86_PAE |
| .set_pte_atomic = xen_set_pte_atomic, |
| .set_pte_present = xen_set_pte_at, |
| .pte_clear = xen_pte_clear, |
| .pmd_clear = xen_pmd_clear, |
| #endif /* CONFIG_X86_PAE */ |
| .set_pud = xen_set_pud_hyper, |
| |
| .make_pmd = xen_make_pmd, |
| .pmd_val = xen_pmd_val, |
| |
| #if PAGETABLE_LEVELS == 4 |
| .pud_val = xen_pud_val, |
| .make_pud = xen_make_pud, |
| .set_pgd = xen_set_pgd_hyper, |
| |
| .alloc_pud = xen_alloc_pte_init, |
| .release_pud = xen_release_pte_init, |
| #endif /* PAGETABLE_LEVELS == 4 */ |
| |
| .activate_mm = xen_activate_mm, |
| .dup_mmap = xen_dup_mmap, |
| .exit_mmap = xen_exit_mmap, |
| |
| .lazy_mode = { |
| .enter = paravirt_enter_lazy_mmu, |
| .leave = xen_leave_lazy, |
| }, |
| |
| .set_fixmap = xen_set_fixmap, |
| }; |
| |
| 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, |
| }; |
| |
| |
| static void __init xen_reserve_top(void) |
| { |
| #ifdef CONFIG_X86_32 |
| unsigned long top = HYPERVISOR_VIRT_START; |
| struct xen_platform_parameters pp; |
| |
| if (HYPERVISOR_xen_version(XENVER_platform_parameters, &pp) == 0) |
| top = pp.virt_start; |
| |
| reserve_top_address(-top + 2 * PAGE_SIZE); |
| #endif /* CONFIG_X86_32 */ |
| } |
| |
| /* |
| * Like __va(), but returns address in the kernel mapping (which is |
| * all we have until the physical memory mapping has been set up. |
| */ |
| static void *__ka(phys_addr_t paddr) |
| { |
| #ifdef CONFIG_X86_64 |
| return (void *)(paddr + __START_KERNEL_map); |
| #else |
| return __va(paddr); |
| #endif |
| } |
| |
| /* Convert a machine address to physical address */ |
| static unsigned long m2p(phys_addr_t maddr) |
| { |
| phys_addr_t paddr; |
| |
| maddr &= PTE_PFN_MASK; |
| paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT; |
| |
| return paddr; |
| } |
| |
| /* Convert a machine address to kernel virtual */ |
| static void *m2v(phys_addr_t maddr) |
| { |
| return __ka(m2p(maddr)); |
| } |
| |
| #ifdef CONFIG_X86_64 |
| static void walk(pgd_t *pgd, unsigned long addr) |
| { |
| unsigned l4idx = pgd_index(addr); |
| unsigned l3idx = pud_index(addr); |
| unsigned l2idx = pmd_index(addr); |
| unsigned l1idx = pte_index(addr); |
| pgd_t l4; |
| pud_t l3; |
| pmd_t l2; |
| pte_t l1; |
| |
| xen_raw_printk("walk %p, %lx -> %d %d %d %d\n", |
| pgd, addr, l4idx, l3idx, l2idx, l1idx); |
| |
| l4 = pgd[l4idx]; |
| xen_raw_printk(" l4: %016lx\n", l4.pgd); |
| xen_raw_printk(" %016lx\n", pgd_val(l4)); |
| |
| l3 = ((pud_t *)(m2v(l4.pgd)))[l3idx]; |
| xen_raw_printk(" l3: %016lx\n", l3.pud); |
| xen_raw_printk(" %016lx\n", pud_val(l3)); |
| |
| l2 = ((pmd_t *)(m2v(l3.pud)))[l2idx]; |
| xen_raw_printk(" l2: %016lx\n", l2.pmd); |
| xen_raw_printk(" %016lx\n", pmd_val(l2)); |
| |
| l1 = ((pte_t *)(m2v(l2.pmd)))[l1idx]; |
| xen_raw_printk(" l1: %016lx\n", l1.pte); |
| xen_raw_printk(" %016lx\n", pte_val(l1)); |
| } |
| #endif |
| |
| static void set_page_prot(void *addr, pgprot_t prot) |
| { |
| unsigned long pfn = __pa(addr) >> PAGE_SHIFT; |
| pte_t pte = pfn_pte(pfn, prot); |
| |
| xen_raw_printk("addr=%p pfn=%lx mfn=%lx prot=%016llx pte=%016llx\n", |
| addr, pfn, get_phys_to_machine(pfn), |
| pgprot_val(prot), pte.pte); |
| |
| if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0)) |
| BUG(); |
| } |
| |
| static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) |
| { |
| unsigned pmdidx, pteidx; |
| unsigned ident_pte; |
| unsigned long pfn; |
| |
| ident_pte = 0; |
| pfn = 0; |
| for(pmdidx = 0; pmdidx < PTRS_PER_PMD && pfn < max_pfn; pmdidx++) { |
| pte_t *pte_page; |
| |
| /* Reuse or allocate a page of ptes */ |
| if (pmd_present(pmd[pmdidx])) |
| pte_page = m2v(pmd[pmdidx].pmd); |
| else { |
| /* Check for free pte pages */ |
| if (ident_pte == ARRAY_SIZE(level1_ident_pgt)) |
| break; |
| |
| pte_page = &level1_ident_pgt[ident_pte]; |
| ident_pte += PTRS_PER_PTE; |
| |
| pmd[pmdidx] = __pmd(__pa(pte_page) | _PAGE_TABLE); |
| } |
| |
| /* Install mappings */ |
| for(pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) { |
| pte_t pte; |
| |
| if (pfn > max_pfn_mapped) |
| max_pfn_mapped = pfn; |
| |
| if (!pte_none(pte_page[pteidx])) |
| continue; |
| |
| pte = pfn_pte(pfn, PAGE_KERNEL_EXEC); |
| pte_page[pteidx] = pte; |
| } |
| } |
| |
| for(pteidx = 0; pteidx < ident_pte; pteidx += PTRS_PER_PTE) |
| set_page_prot(&level1_ident_pgt[pteidx], PAGE_KERNEL_RO); |
| |
| set_page_prot(pmd, PAGE_KERNEL_RO); |
| } |
| |
| #ifdef CONFIG_X86_64 |
| static void convert_pfn_mfn(void *v) |
| { |
| pte_t *pte = v; |
| int i; |
| |
| /* All levels are converted the same way, so just treat them |
| as ptes. */ |
| for(i = 0; i < PTRS_PER_PTE; i++) |
| pte[i] = xen_make_pte(pte[i].pte); |
| } |
| |
| /* |
| * Set up the inital kernel pagetable. |
| * |
| * We can construct this by grafting the Xen provided pagetable into |
| * head_64.S's preconstructed pagetables. We copy the Xen L2's into |
| * level2_ident_pgt, level2_kernel_pgt and level2_fixmap_pgt. This |
| * means that only the kernel has a physical mapping to start with - |
| * but that's enough to get __va working. We need to fill in the rest |
| * of the physical mapping once some sort of allocator has been set |
| * up. |
| */ |
| static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) |
| { |
| pud_t *l3; |
| pmd_t *l2; |
| |
| /* Zap identity mapping */ |
| init_level4_pgt[0] = __pgd(0); |
| |
| /* Pre-constructed entries are in pfn, so convert to mfn */ |
| convert_pfn_mfn(init_level4_pgt); |
| convert_pfn_mfn(level3_ident_pgt); |
| convert_pfn_mfn(level3_kernel_pgt); |
| |
| l3 = m2v(pgd[pgd_index(__START_KERNEL_map)].pgd); |
| l2 = m2v(l3[pud_index(__START_KERNEL_map)].pud); |
| |
| memcpy(level2_ident_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD); |
| memcpy(level2_kernel_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD); |
| |
| l3 = m2v(pgd[pgd_index(__START_KERNEL_map + PMD_SIZE)].pgd); |
| l2 = m2v(l3[pud_index(__START_KERNEL_map + PMD_SIZE)].pud); |
| memcpy(level2_fixmap_pgt, l2, sizeof(pmd_t) * PTRS_PER_PMD); |
| |
| /* Set up identity map */ |
| xen_map_identity_early(level2_ident_pgt, max_pfn); |
| |
| /* Make pagetable pieces RO */ |
| set_page_prot(init_level4_pgt, PAGE_KERNEL_RO); |
| set_page_prot(level3_ident_pgt, PAGE_KERNEL_RO); |
| set_page_prot(level3_kernel_pgt, PAGE_KERNEL_RO); |
| set_page_prot(level3_user_vsyscall, PAGE_KERNEL_RO); |
| set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO); |
| set_page_prot(level2_fixmap_pgt, PAGE_KERNEL_RO); |
| |
| /* Pin down new L4 */ |
| pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE, |
| PFN_DOWN(__pa_symbol(init_level4_pgt))); |
| |
| /* Unpin Xen-provided one */ |
| pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd))); |
| |
| /* Switch over */ |
| pgd = init_level4_pgt; |
| |
| /* |
| * At this stage there can be no user pgd, and no page |
| * structure to attach it to, so make sure we just set kernel |
| * pgd. |
| */ |
| xen_mc_batch(); |
| __xen_write_cr3(true, __pa(pgd)); |
| xen_mc_issue(PARAVIRT_LAZY_CPU); |
| |
| reserve_early(__pa(xen_start_info->pt_base), |
| __pa(xen_start_info->pt_base + |
| xen_start_info->nr_pt_frames * PAGE_SIZE), |
| "XEN PAGETABLES"); |
| |
| return pgd; |
| } |
| #else /* !CONFIG_X86_64 */ |
| static pmd_t level2_kernel_pgt[PTRS_PER_PMD] __page_aligned_bss; |
| |
| static __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) |
| { |
| pmd_t *kernel_pmd; |
| |
| init_pg_tables_start = __pa(pgd); |
| init_pg_tables_end = __pa(pgd) + xen_start_info->nr_pt_frames*PAGE_SIZE; |
| max_pfn_mapped = PFN_DOWN(init_pg_tables_end + 512*1024); |
| |
| kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd); |
| memcpy(level2_kernel_pgt, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD); |
| |
| xen_map_identity_early(level2_kernel_pgt, max_pfn); |
| |
| memcpy(swapper_pg_dir, pgd, sizeof(pgd_t) * PTRS_PER_PGD); |
| set_pgd(&swapper_pg_dir[KERNEL_PGD_BOUNDARY], |
| __pgd(__pa(level2_kernel_pgt) | _PAGE_PRESENT)); |
| |
| set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO); |
| set_page_prot(swapper_pg_dir, PAGE_KERNEL_RO); |
| set_page_prot(empty_zero_page, PAGE_KERNEL_RO); |
| |
| pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd))); |
| |
| xen_write_cr3(__pa(swapper_pg_dir)); |
| |
| pin_pagetable_pfn(MMUEXT_PIN_L3_TABLE, PFN_DOWN(__pa(swapper_pg_dir))); |
| |
| return swapper_pg_dir; |
| } |
| #endif /* CONFIG_X86_64 */ |
| |
| /* First C function to be called on Xen boot */ |
| asmlinkage void __init xen_start_kernel(void) |
| { |
| pgd_t *pgd; |
| |
| if (!xen_start_info) |
| return; |
| |
| 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_irq_ops = xen_irq_ops; |
| pv_apic_ops = xen_apic_ops; |
| pv_mmu_ops = xen_mmu_ops; |
| |
| 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 |
| /* Disable until direct per-cpu data access. */ |
| have_vcpu_info_placement = 0; |
| x86_64_init_pda(); |
| #endif |
| |
| 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 (!is_initial_xendomain()) |
| __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); |
| |
| /* 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]; |
| |
| 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 (!is_initial_xendomain()) { |
| 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"); |
| |
| #if 0 |
| xen_raw_printk("&boot_params=%p __pa(&boot_params)=%lx __va(__pa(&boot_params))=%lx\n", |
| &boot_params, __pa_symbol(&boot_params), |
| __va(__pa_symbol(&boot_params))); |
| |
| walk(pgd, &boot_params); |
| walk(pgd, __va(__pa(&boot_params))); |
| #endif |
| |
| /* Start the world */ |
| #ifdef CONFIG_X86_32 |
| i386_start_kernel(); |
| #else |
| x86_64_start_reservations((char *)__pa_symbol(&boot_params)); |
| #endif |
| } |