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Diffstat (limited to 'arch/x86/xen/enlighten.c')
| -rw-r--r-- | arch/x86/xen/enlighten.c | 1146 |
1 files changed, 1146 insertions, 0 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c new file mode 100644 index 000000000000..f01bfcd4bdee --- /dev/null +++ b/arch/x86/xen/enlighten.c @@ -0,0 +1,1146 @@ +/* + * 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/smp.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 <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/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(enum paravirt_lazy_mode, xen_lazy_mode); + +DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); +DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info); +DEFINE_PER_CPU(unsigned long, xen_cr3); + +struct start_info *xen_start_info; +EXPORT_SYMBOL_GPL(xen_start_info); + +static /* __initdata */ struct shared_info 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 *)&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 __init xen_vcpu_setup(int cpu) +{ + struct vcpu_register_vcpu_info info; + int err; + struct vcpu_info *vcpup; + + 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 %x, 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); + } +} + +static void __init xen_banner(void) +{ + printk(KERN_INFO "Booting paravirtualized kernel on %s\n", + paravirt_ops.name); + printk(KERN_INFO "Hypervisor signature: %s\n", xen_start_info->magic); +} + +static void xen_cpuid(unsigned int *eax, unsigned int *ebx, + unsigned int *ecx, unsigned int *edx) +{ + unsigned maskedx = ~0; + + /* + * Mask out inconvenient features, to try and disable as many + * unsupported kernel subsystems as possible. + */ + if (*eax == 1) + maskedx = ~((1 << X86_FEATURE_APIC) | /* disable APIC */ + (1 << X86_FEATURE_ACPI) | /* disable ACPI */ + (1 << X86_FEATURE_ACC)); /* thermal monitoring */ + + asm(XEN_EMULATE_PREFIX "cpuid" + : "=a" (*eax), + "=b" (*ebx), + "=c" (*ecx), + "=d" (*edx) + : "0" (*eax), "2" (*ecx)); + *edx &= 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; + + /* 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 = 0; + preempt_enable_no_resched(); + + /* 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, 0) != 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_set_lazy_mode(enum paravirt_lazy_mode mode) +{ + BUG_ON(preemptible()); + + switch (mode) { + case PARAVIRT_LAZY_NONE: + BUG_ON(x86_read_percpu(xen_lazy_mode) == PARAVIRT_LAZY_NONE); + break; + + case PARAVIRT_LAZY_MMU: + case PARAVIRT_LAZY_CPU: + BUG_ON(x86_read_percpu(xen_lazy_mode) != PARAVIRT_LAZY_NONE); + break; + + case PARAVIRT_LAZY_FLUSH: + /* flush if necessary, but don't change state */ + if (x86_read_percpu(xen_lazy_mode) != PARAVIRT_LAZY_NONE) + xen_mc_flush(); + return; + } + + xen_mc_flush(); + x86_write_percpu(xen_lazy_mode, mode); +} + +static unsigned long xen_store_tr(void) +{ + return 0; +} + +static void xen_set_ldt(const void *addr, unsigned entries) +{ + unsigned long linear_addr = (unsigned long)addr; + struct mmuext_op *op; + struct multicall_space mcs = xen_mc_entry(sizeof(*op)); + + op = mcs.args; + op->cmd = MMUEXT_SET_LDT; + if (linear_addr) { + /* ldt my be vmalloced, use arbitrary_virt_to_machine */ + xmaddr_t maddr; + maddr = arbitrary_virt_to_machine((unsigned long)addr); + linear_addr = (unsigned long)maddr.maddr; + } + op->arg1.linear_addr = linear_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 Xgt_desc_struct *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) +{ + 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); + + /* + * 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. + */ + if (xen_get_lazy_mode() == PARAVIRT_LAZY_CPU) + loadsegment(gs, 0); +} + +static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, + u32 low, u32 high) +{ + unsigned long lp = (unsigned long)&dt[entrynum]; + xmaddr_t mach_lp = virt_to_machine(lp); + u64 entry = (u64)high << 32 | low; + + preempt_disable(); + + xen_mc_flush(); + if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry)) + BUG(); + + preempt_enable(); +} + +static int cvt_gate_to_trap(int vector, u32 low, u32 high, + struct trap_info *info) +{ + u8 type, dpl; + + type = (high >> 8) & 0x1f; + dpl = (high >> 13) & 3; + + if (type != 0xf && type != 0xe) + return 0; + + info->vector = vector; + info->address = (high & 0xffff0000) | (low & 0x0000ffff); + info->cs = low >> 16; + info->flags = dpl; + /* interrupt gates clear IF */ + if (type == 0xe) + info->flags |= 4; + + return 1; +} + +/* Locations of each CPU's IDT */ +static DEFINE_PER_CPU(struct Xgt_desc_struct, 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(struct desc_struct *dt, int entrynum, + u32 low, u32 high) +{ + 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(); + + write_dt_entry(dt, entrynum, low, high); + + if (p >= start && (p + 8) <= end) { + struct trap_info info[2]; + + info[1].address = 0; + + if (cvt_gate_to_trap(entrynum, low, high, &info[0])) + if (HYPERVISOR_set_trap_table(info)) + BUG(); + } + + preempt_enable(); +} + +static void xen_convert_trap_info(const struct Xgt_desc_struct *desc, + struct trap_info *traps) +{ + unsigned in, out, count; + + count = (desc->size+1) / 8; + BUG_ON(count > 256); + + for (in = out = 0; in < count; in++) { + const u32 *entry = (u32 *)(desc->address + in * 8); + + if (cvt_gate_to_trap(in, entry[0], entry[1], &traps[out])) + out++; + } + traps[out].address = 0; +} + +void xen_copy_trap_info(struct trap_info *traps) +{ + const struct Xgt_desc_struct *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 Xgt_desc_struct *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, + u32 low, u32 high) +{ + preempt_disable(); + + switch ((high >> 8) & 0xff) { + case DESCTYPE_LDT: + case DESCTYPE_TSS: + /* ignore */ + break; + + default: { + xmaddr_t maddr = virt_to_machine(&dt[entry]); + u64 desc = (u64)high << 32 | low; + + xen_mc_flush(); + if (HYPERVISOR_update_descriptor(maddr.maddr, desc)) + BUG(); + } + + } + + preempt_enable(); +} + +static void xen_load_esp0(struct tss_struct *tss, + struct thread_struct *thread) +{ + struct multicall_space mcs = xen_mc_entry(0); + MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->esp0); + 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 unsigned long xen_apic_read(unsigned long reg) +{ + return 0; +} + +static void xen_apic_write(unsigned long reg, unsigned long 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 = 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); +} + +static void xen_flush_tlb_single(unsigned long addr) +{ + struct mmuext_op *op; + struct multicall_space 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); +} + +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_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) +{ + /* Just ignore cr4 changes; Xen doesn't allow us to do + anything anyway. */ +} + +static unsigned long xen_read_cr3(void) +{ + return x86_read_percpu(xen_cr3); +} + +static void xen_write_cr3(unsigned long cr3) +{ + BUG_ON(preemptible()); + + if (cr3 == x86_read_percpu(xen_cr3)) { + /* just a simple tlb flush */ + xen_flush_tlb(); + return; + } + + x86_write_percpu(xen_cr3, cr3); + + + { + struct mmuext_op *op; + struct multicall_space mcs = xen_mc_entry(sizeof(*op)); + unsigned long mfn = pfn_to_mfn(PFN_DOWN(cr3)); + + op = mcs.args; + op->cmd = MMUEXT_NEW_BASEPTR; + op->arg1.mfn = mfn; + + MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); + + xen_mc_issue(PARAVIRT_LAZY_CPU); + } +} + +/* Early in boot, while setting up the initial pagetable, assume + everything is pinned. */ +static __init void xen_alloc_pt_init(struct mm_struct *mm, u32 pfn) +{ + BUG_ON(mem_map); /* should only be used early */ + make_lowmem_page_readonly(__va(PFN_PHYS(pfn))); +} + +/* This needs to make sure the new pte page is pinned iff its being + attached to a pinned pagetable. */ +static void xen_alloc_pt(struct mm_struct *mm, u32 pfn) +{ + 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))); + else + /* make sure there are no stray mappings of + this page */ + kmap_flush_unused(); + } +} + +/* This should never happen until we're OK to use struct page */ +static void xen_release_pt(u32 pfn) +{ + struct page *page = pfn_to_page(pfn); + + if (PagePinned(page)) { + if (!PageHighMem(page)) + make_lowmem_page_readwrite(__va(PFN_PHYS(pfn))); + } +} + +#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) +{ + pgd_t *xen_pgd = (pgd_t *)xen_start_info->pt_base; + + /* special set_pte for pagetable initialization */ + paravirt_ops.set_pte = xen_set_pte_init; + + init_mm.pgd = base; + /* + * copy top-level of Xen-supplied pagetable into place. For + * !PAE we can use this as-is, but for PAE it is a stand-in + * while we copy the pmd pages. + */ + memcpy(base, xen_pgd, PTRS_PER_PGD * sizeof(pgd_t)); + + if (PTRS_PER_PMD > 1) { + int i; + /* + * For PAE, need to allocate new pmds, rather than + * share Xen's, since Xen doesn't like pmd's being + * shared between address spaces. + */ + for (i = 0; i < PTRS_PER_PGD; i++) { + if (pgd_val_ma(xen_pgd[i]) & _PAGE_PRESENT) { + pmd_t *pmd = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE); + + memcpy(pmd, (void *)pgd_page_vaddr(xen_pgd[i]), + PAGE_SIZE); + + make_lowmem_page_readonly(pmd); + + set_pgd(&base[i], __pgd(1 + __pa(pmd))); + } else + pgd_clear(&base[i]); + } + } + + /* make sure zero_page is mapped RO so we can use it in pagetables */ + make_lowmem_page_readonly(empty_zero_page); + make_lowmem_page_readonly(base); + /* + * Switch to new pagetable. This is done before + * pagetable_init has done anything so that the new pages + * added to the table can be prepared properly for Xen. + */ + xen_write_cr3(__pa(base)); +} + +static __init void xen_pagetable_setup_done(pgd_t *base) +{ + /* This will work as long as patching hasn't happened yet + (which it hasn't) */ + paravirt_ops.alloc_pt = xen_alloc_pt; + paravirt_ops.set_pte = xen_set_pte; + + if (!xen_feature(XENFEAT_auto_translated_physmap)) { + /* + * Create a mapping for the shared info page. + * Should be set_fixmap(), but shared_info is a machine + * address with no corresponding pseudo-phys address. + */ + set_pte_mfn(fix_to_virt(FIX_PARAVIRT_BOOTMAP), + PFN_DOWN(xen_start_info->shared_info), + PAGE_KERNEL); + + 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); + + /* Actually pin the pagetable down, but we can't set PG_pinned + yet because the page structures don't exist yet. */ + { + struct mmuext_op op; +#ifdef CONFIG_X86_PAE + op.cmd = MMUEXT_PIN_L3_TABLE; +#else + op.cmd = MMUEXT_PIN_L3_TABLE; +#endif + op.arg1.mfn = pfn_to_mfn(PFN_DOWN(__pa(base))); + if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF)) + BUG(); + } +} + +/* This is called once we have the cpu_possible_map */ +void __init 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"); + + paravirt_ops.save_fl = xen_save_fl_direct; + paravirt_ops.restore_fl = xen_restore_fl_direct; + paravirt_ops.irq_disable = xen_irq_disable_direct; + paravirt_ops.irq_enable = xen_irq_enable_direct; + paravirt_ops.read_cr2 = xen_read_cr2_direct; + paravirt_ops.iret = xen_iret_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(x) \ + case PARAVIRT_PATCH(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(irq_enable); + SITE(irq_disable); + SITE(save_fl); + SITE(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 paravirt_ops xen_paravirt_ops __initdata = { + .paravirt_enabled = 1, + .shared_kernel_pmd = 0, + + .name = "Xen", + .banner = xen_banner, + + .patch = xen_patch, + + .memory_setup = xen_memory_setup, + .arch_setup = xen_arch_setup, + .init_IRQ = xen_init_IRQ, + .post_allocator_init = xen_mark_init_mm_pinned, + + .time_init = xen_time_init, + .set_wallclock = xen_set_wallclock, + .get_wallclock = xen_get_wallclock, + .get_cpu_khz = xen_cpu_khz, + .sched_clock = xen_sched_clock, + + .cpuid = xen_cpuid, + + .set_debugreg = xen_set_debugreg, + .get_debugreg = xen_get_debugreg, + + .clts = native_clts, + + .read_cr0 = native_read_cr0, + .write_cr0 = native_write_cr0, + + .read_cr2 = xen_read_cr2, + .write_cr2 = xen_write_cr2, + + .read_cr3 = xen_read_cr3, + .write_cr3 = xen_write_cr3, + + .read_cr4 = native_read_cr4, + .read_cr4_safe = native_read_cr4_safe, + .write_cr4 = xen_write_cr4, + + .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, + .wbinvd = native_wbinvd, + + .read_msr = native_read_msr_safe, + .write_msr = native_write_msr_safe, + .read_tsc = native_read_tsc, + .read_pmc = native_read_pmc, + + .iret = (void *)&hypercall_page[__HYPERVISOR_iret], + .irq_enable_sysexit = NULL, /* never called */ + + .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, + + .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_esp0 = xen_load_esp0, + + .set_iopl_mask = xen_set_iopl_mask, + .io_delay = xen_io_delay, + +#ifdef CONFIG_X86_LOCAL_APIC + .apic_write = xen_apic_write, + .apic_write_atomic = xen_apic_write, + .apic_read = xen_apic_read, + .setup_boot_clock = paravirt_nop, + .setup_secondary_clock = paravirt_nop, + .startup_ipi_hook = paravirt_nop, +#endif + + .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, + + .pagetable_setup_start = xen_pagetable_setup_start, + .pagetable_setup_done = xen_pagetable_setup_done, + + .alloc_pt = xen_alloc_pt_init, + .release_pt = xen_release_pt, + .alloc_pd = paravirt_nop, + .alloc_pd_clone = paravirt_nop, + .release_pd = paravirt_nop, + +#ifdef CONFIG_HIGHPTE + .kmap_atomic_pte = xen_kmap_atomic_pte, +#endif + + .set_pte = NULL, /* see xen_pagetable_setup_* */ + .set_pte_at = xen_set_pte_at, + .set_pmd = xen_set_pmd, + + .pte_val = xen_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, + .set_pud = xen_set_pud, + .pte_clear = xen_pte_clear, + .pmd_clear = xen_pmd_clear, + + .make_pmd = xen_make_pmd, + .pmd_val = xen_pmd_val, +#endif /* PAE */ + + .activate_mm = xen_activate_mm, + .dup_mmap = xen_dup_mmap, + .exit_mmap = xen_exit_mmap, + + .set_lazy_mode = xen_set_lazy_mode, +}; + +#ifdef CONFIG_SMP +static const struct smp_ops xen_smp_ops __initdata = { + .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu, + .smp_prepare_cpus = xen_smp_prepare_cpus, + .cpu_up = xen_cpu_up, + .smp_cpus_done = xen_smp_cpus_done, + + .smp_send_stop = xen_smp_send_stop, + .smp_send_reschedule = xen_smp_send_reschedule, + .smp_call_function_mask = xen_smp_call_function_mask, +}; +#endif /* CONFIG_SMP */ + +static void xen_reboot(int reason) +{ +#ifdef CONFIG_SMP + smp_send_stop(); +#endif + + if (HYPERVISOR_sched_op(SCHEDOP_shutdown, reason)) + 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; + + BUG_ON(memcmp(xen_start_info->magic, "xen-3.0", 7) != 0); + + /* Install Xen paravirt ops */ + paravirt_ops = xen_paravirt_ops; + machine_ops = xen_machine_ops; + +#ifdef CONFIG_SMP + smp_ops = xen_smp_ops; +#endif + + xen_setup_features(); + + /* Get mfn list */ + if (!xen_feature(XENFEAT_auto_translated_physmap)) + phys_to_machine_mapping = (unsigned long *)xen_start_info->mfn_list; + + pgd = (pgd_t *)xen_start_info->pt_base; + + init_pg_tables_end = __pa(pgd) + xen_start_info->nr_pt_frames*PAGE_SIZE; + + init_mm.pgd = pgd; /* use the Xen pagetables to start */ + + /* keep using Xen gdt for now; no urgent need to change it */ + + x86_write_percpu(xen_cr3, __pa(pgd)); + +#ifdef CONFIG_SMP + /* Don't do the full vcpu_info placement stuff until we have a + possible map. */ + per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; +#else + /* May as well do it now, since there's no good time to call + it later on UP. */ + xen_setup_vcpu_info_placement(); +#endif + + paravirt_ops.kernel_rpl = 1; + if (xen_feature(XENFEAT_supervisor_mode_kernel)) + paravirt_ops.kernel_rpl = 0; + + /* set the limit of our address space */ + reserve_top_address(-HYPERVISOR_VIRT_START + 2 * PAGE_SIZE); + + /* 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); + + /* Poke various useful things into boot_params */ + LOADER_TYPE = (9 << 4) | 0; + INITRD_START = xen_start_info->mod_start ? __pa(xen_start_info->mod_start) : 0; + INITRD_SIZE = xen_start_info->mod_len; + + /* Start the world */ + start_kernel(); +} |
