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-rw-r--r--arch/i386/Makefile3
-rw-r--r--arch/i386/kernel/entry.S71
-rw-r--r--arch/i386/kernel/head.S5
-rw-r--r--arch/i386/kernel/vmlinux.lds.S1
-rw-r--r--arch/i386/xen/Makefile1
-rw-r--r--arch/i386/xen/enlighten.c745
-rw-r--r--arch/i386/xen/features.c29
-rw-r--r--arch/i386/xen/multicalls.c89
-rw-r--r--arch/i386/xen/multicalls.h45
-rw-r--r--arch/i386/xen/setup.c97
-rw-r--r--arch/i386/xen/xen-head.S36
-rw-r--r--arch/i386/xen/xen-ops.h31
12 files changed, 1152 insertions, 1 deletions
diff --git a/arch/i386/Makefile b/arch/i386/Makefile
index 181cc29a7c4..01f0ff0daaf 100644
--- a/arch/i386/Makefile
+++ b/arch/i386/Makefile
@@ -93,6 +93,9 @@ mflags-$(CONFIG_X86_ES7000) := -Iinclude/asm-i386/mach-es7000
mcore-$(CONFIG_X86_ES7000) := mach-default
core-$(CONFIG_X86_ES7000) := arch/i386/mach-es7000/
+# Xen paravirtualization support
+core-$(CONFIG_XEN) += arch/i386/xen/
+
# default subarch .h files
mflags-y += -Iinclude/asm-i386/mach-default
diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
index 3c3c220488c..ffb23654427 100644
--- a/arch/i386/kernel/entry.S
+++ b/arch/i386/kernel/entry.S
@@ -1023,6 +1023,77 @@ ENTRY(kernel_thread_helper)
CFI_ENDPROC
ENDPROC(kernel_thread_helper)
+#ifdef CONFIG_XEN
+ENTRY(xen_hypervisor_callback)
+ CFI_STARTPROC
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ TRACE_IRQS_OFF
+ mov %esp, %eax
+ call xen_evtchn_do_upcall
+ jmp ret_from_intr
+ CFI_ENDPROC
+ENDPROC(xen_hypervisor_callback)
+
+# Hypervisor uses this for application faults while it executes.
+# We get here for two reasons:
+# 1. Fault while reloading DS, ES, FS or GS
+# 2. Fault while executing IRET
+# Category 1 we fix up by reattempting the load, and zeroing the segment
+# register if the load fails.
+# Category 2 we fix up by jumping to do_iret_error. We cannot use the
+# normal Linux return path in this case because if we use the IRET hypercall
+# to pop the stack frame we end up in an infinite loop of failsafe callbacks.
+# We distinguish between categories by maintaining a status value in EAX.
+ENTRY(xen_failsafe_callback)
+ CFI_STARTPROC
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ movl $1,%eax
+1: mov 4(%esp),%ds
+2: mov 8(%esp),%es
+3: mov 12(%esp),%fs
+4: mov 16(%esp),%gs
+ testl %eax,%eax
+ popl %eax
+ CFI_ADJUST_CFA_OFFSET -4
+ lea 16(%esp),%esp
+ CFI_ADJUST_CFA_OFFSET -16
+ jz 5f
+ addl $16,%esp
+ jmp iret_exc # EAX != 0 => Category 2 (Bad IRET)
+5: pushl $0 # EAX == 0 => Category 1 (Bad segment)
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ jmp ret_from_exception
+ CFI_ENDPROC
+
+.section .fixup,"ax"
+6: xorl %eax,%eax
+ movl %eax,4(%esp)
+ jmp 1b
+7: xorl %eax,%eax
+ movl %eax,8(%esp)
+ jmp 2b
+8: xorl %eax,%eax
+ movl %eax,12(%esp)
+ jmp 3b
+9: xorl %eax,%eax
+ movl %eax,16(%esp)
+ jmp 4b
+.previous
+.section __ex_table,"a"
+ .align 4
+ .long 1b,6b
+ .long 2b,7b
+ .long 3b,8b
+ .long 4b,9b
+.previous
+ENDPROC(xen_failsafe_callback)
+
+#endif /* CONFIG_XEN */
+
.section .rodata,"a"
#include "syscall_table.S"
diff --git a/arch/i386/kernel/head.S b/arch/i386/kernel/head.S
index 82714668d43..7c52b222207 100644
--- a/arch/i386/kernel/head.S
+++ b/arch/i386/kernel/head.S
@@ -510,7 +510,8 @@ ENTRY(_stext)
/*
* BSS section
*/
-.section ".bss.page_aligned","w"
+.section ".bss.page_aligned","wa"
+ .align PAGE_SIZE_asm
ENTRY(swapper_pg_dir)
.fill 1024,4,0
ENTRY(swapper_pg_pmd)
@@ -538,6 +539,8 @@ fault_msg:
.ascii "Int %d: CR2 %p err %p EIP %p CS %p flags %p\n"
.asciz "Stack: %p %p %p %p %p %p %p %p\n"
+#include "../xen/xen-head.S"
+
/*
* The IDT and GDT 'descriptors' are a strange 48-bit object
* only used by the lidt and lgdt instructions. They are not
diff --git a/arch/i386/kernel/vmlinux.lds.S b/arch/i386/kernel/vmlinux.lds.S
index aa87b06c7c8..00f1bc47d3a 100644
--- a/arch/i386/kernel/vmlinux.lds.S
+++ b/arch/i386/kernel/vmlinux.lds.S
@@ -88,6 +88,7 @@ SECTIONS
. = ALIGN(4096);
.data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
+ *(.data.page_aligned)
*(.data.idt)
}
diff --git a/arch/i386/xen/Makefile b/arch/i386/xen/Makefile
new file mode 100644
index 00000000000..60bc1cfb101
--- /dev/null
+++ b/arch/i386/xen/Makefile
@@ -0,0 +1 @@
+obj-y := enlighten.o setup.o features.o multicalls.o
diff --git a/arch/i386/xen/enlighten.c b/arch/i386/xen/enlighten.c
new file mode 100644
index 00000000000..2d484f9320d
--- /dev/null
+++ b/arch/i386/xen/enlighten.c
@@ -0,0 +1,745 @@
+/*
+ * 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/percpu.h>
+#include <linux/delay.h>
+#include <linux/start_kernel.h>
+#include <linux/sched.h>
+#include <linux/bootmem.h>
+#include <linux/module.h>
+
+#include <xen/interface/xen.h>
+#include <xen/interface/physdev.h>
+#include <xen/interface/vcpu.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 "xen-ops.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 void xen_vcpu_setup(int cpu)
+{
+ per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
+}
+
+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;
+
+ preempt_disable();
+ vcpu = x86_read_percpu(xen_vcpu);
+ /* flag has opposite sense of mask */
+ flags = !vcpu->evtchn_upcall_mask;
+ preempt_enable();
+
+ /* 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;
+
+ preempt_disable();
+
+ /* convert from IF type flag */
+ flags = !(flags & X86_EFLAGS_IF);
+ vcpu = x86_read_percpu(xen_vcpu);
+ vcpu->evtchn_upcall_mask = flags;
+
+ if (flags == 0) {
+ /* Unmask then check (avoid races). We're only protecting
+ against updates by this CPU, so there's no need for
+ anything stronger. */
+ barrier();
+
+ if (unlikely(vcpu->evtchn_upcall_pending))
+ force_evtchn_callback();
+ preempt_enable();
+ } else
+ preempt_enable_no_resched();
+}
+
+static void xen_irq_disable(void)
+{
+ struct vcpu_info *vcpu;
+ preempt_disable();
+ vcpu = x86_read_percpu(xen_vcpu);
+ vcpu->evtchn_upcall_mask = 1;
+ preempt_enable_no_resched();
+}
+
+static void xen_irq_enable(void)
+{
+ struct vcpu_info *vcpu;
+
+ preempt_disable();
+ vcpu = x86_read_percpu(xen_vcpu);
+ vcpu->evtchn_upcall_mask = 0;
+
+ /* Unmask then check (avoid races). We're only protecting
+ against updates by this CPU, so there's no need for
+ anything stronger. */
+ barrier();
+
+ if (unlikely(vcpu->evtchn_upcall_pending))
+ force_evtchn_callback();
+ preempt_enable();
+}
+
+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)
+{
+ 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);
+}
+
+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;
+
+ xen_mc_flush();
+ if (HYPERVISOR_update_descriptor(mach_lp.maddr, entry))
+ BUG();
+}
+
+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)
+{
+
+ int cpu = smp_processor_id();
+ unsigned long p = (unsigned long)&dt[entrynum];
+ unsigned long start = per_cpu(idt_desc, cpu).address;
+ unsigned long end = start + per_cpu(idt_desc, cpu).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();
+ }
+}
+
+/* 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];
+
+ int cpu = smp_processor_id();
+ unsigned in, out, count;
+
+ per_cpu(idt_desc, cpu) = *desc;
+
+ count = (desc->size+1) / 8;
+ BUG_ON(count > 256);
+
+ spin_lock(&lock);
+ 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;
+
+ 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)
+{
+ 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();
+ }
+
+ }
+}
+
+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;
+}
+#endif
+
+static void xen_flush_tlb(void)
+{
+ struct mmuext_op op;
+
+ op.cmd = MMUEXT_TLB_FLUSH_LOCAL;
+ if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
+ BUG();
+}
+
+static void xen_flush_tlb_single(unsigned long addr)
+{
+ struct mmuext_op op;
+
+ op.cmd = MMUEXT_INVLPG_LOCAL;
+ op.arg1.linear_addr = addr & PAGE_MASK;
+ if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
+ BUG();
+}
+
+static unsigned long xen_read_cr2(void)
+{
+ return x86_read_percpu(xen_vcpu)->arch.cr2;
+}
+
+static void xen_write_cr4(unsigned long cr4)
+{
+ /* never allow TSC to be disabled */
+ native_write_cr4(cr4 & ~X86_CR4_TSD);
+}
+
+/*
+ * Page-directory addresses above 4GB do not fit into architectural %cr3.
+ * When accessing %cr3, or equivalent field in vcpu_guest_context, guests
+ * must use the following accessor macros to pack/unpack valid MFNs.
+ *
+ * Note that Xen is using the fact that the pagetable base is always
+ * page-aligned, and putting the 12 MSB of the address into the 12 LSB
+ * of cr3.
+ */
+#define xen_pfn_to_cr3(pfn) (((unsigned)(pfn) << 12) | ((unsigned)(pfn) >> 20))
+#define xen_cr3_to_pfn(cr3) (((unsigned)(cr3) >> 12) | ((unsigned)(cr3) << 20))
+
+static unsigned long xen_read_cr3(void)
+{
+ return x86_read_percpu(xen_cr3);
+}
+
+static void xen_write_cr3(unsigned long cr3)
+{
+ 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);
+ }
+}
+
+static void xen_alloc_pt(struct mm_struct *mm, u32 pfn)
+{
+ /* XXX pfn isn't necessarily a lowmem page */
+ make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
+}
+
+static void xen_alloc_pd(u32 pfn)
+{
+ make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
+}
+
+static void xen_release_pd(u32 pfn)
+{
+ make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
+}
+
+static void xen_release_pt(u32 pfn)
+{
+ make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
+}
+
+static void xen_alloc_pd_clone(u32 pfn, u32 clonepfn,
+ u32 start, u32 count)
+{
+ xen_alloc_pd(pfn);
+}
+
+static __init void xen_pagetable_setup_start(pgd_t *base)
+{
+ pgd_t *xen_pgd = (pgd_t *)xen_start_info->pt_base;
+
+ 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);
+
+ xen_alloc_pd(PFN_DOWN(__pa(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)
+{
+ 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.
+ */
+#if 0
+ set_pte_mfn(fix_to_virt(FIX_PARAVIRT_BOOTMAP),
+ PFN_DOWN(xen_start_info->shared_info),
+ PAGE_KERNEL);
+#endif
+
+ 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);
+
+#if 0
+ xen_pgd_pin(base);
+#endif
+
+ xen_vcpu_setup(smp_processor_id());
+}
+
+static const struct paravirt_ops xen_paravirt_ops __initdata = {
+ .paravirt_enabled = 1,
+ .shared_kernel_pmd = 0,
+
+ .name = "Xen",
+ .banner = xen_banner,
+
+ .patch = paravirt_patch_default,
+
+ .memory_setup = xen_memory_setup,
+ .arch_setup = xen_arch_setup,
+
+ .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 = native_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 = paravirt_nop,
+ .apic_write_atomic = paravirt_nop,
+ .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,
+
+ .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,
+ .alloc_pd = xen_alloc_pd,
+ .alloc_pd_clone = xen_alloc_pd_clone,
+ .release_pd = xen_release_pd,
+ .release_pt = xen_release_pt,
+
+ .set_lazy_mode = xen_set_lazy_mode,
+};
+
+/* 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;
+
+ 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));
+ xen_vcpu_setup(0);
+
+ 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();
+}
diff --git a/arch/i386/xen/features.c b/arch/i386/xen/features.c
new file mode 100644
index 00000000000..0707714e40d
--- /dev/null
+++ b/arch/i386/xen/features.c
@@ -0,0 +1,29 @@
+/******************************************************************************
+ * features.c
+ *
+ * Xen feature flags.
+ *
+ * Copyright (c) 2006, Ian Campbell, XenSource Inc.
+ */
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/module.h>
+#include <asm/xen/hypervisor.h>
+#include <xen/features.h>
+
+u8 xen_features[XENFEAT_NR_SUBMAPS * 32] __read_mostly;
+EXPORT_SYMBOL_GPL(xen_features);
+
+void xen_setup_features(void)
+{
+ struct xen_feature_info fi;
+ int i, j;
+
+ for (i = 0; i < XENFEAT_NR_SUBMAPS; i++) {
+ fi.submap_idx = i;
+ if (HYPERVISOR_xen_version(XENVER_get_features, &fi) < 0)
+ break;
+ for (j = 0; j < 32; j++)
+ xen_features[i * 32 + j] = !!(fi.submap & 1<<j);
+ }
+}
diff --git a/arch/i386/xen/multicalls.c b/arch/i386/xen/multicalls.c
new file mode 100644
index 00000000000..869f9833f08
--- /dev/null
+++ b/arch/i386/xen/multicalls.c
@@ -0,0 +1,89 @@
+/*
+ * Xen hypercall batching.
+ *
+ * Xen allows multiple hypercalls to be issued at once, using the
+ * multicall interface. This allows the cost of trapping into the
+ * hypervisor to be amortized over several calls.
+ *
+ * This file implements a simple interface for multicalls. There's a
+ * per-cpu buffer of outstanding multicalls. When you want to queue a
+ * multicall for issuing, you can allocate a multicall slot for the
+ * call and its arguments, along with storage for space which is
+ * pointed to by the arguments (for passing pointers to structures,
+ * etc). When the multicall is actually issued, all the space for the
+ * commands and allocated memory is freed for reuse.
+ *
+ * Multicalls are flushed whenever any of the buffers get full, or
+ * when explicitly requested. There's no way to get per-multicall
+ * return results back. It will BUG if any of the multicalls fail.
+ *
+ * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
+ */
+#include <linux/percpu.h>
+
+#include <asm/xen/hypercall.h>
+
+#include "multicalls.h"
+
+#define MC_BATCH 8
+#define MC_ARGS (MC_BATCH * 32 / sizeof(u64))
+
+struct mc_buffer {
+ struct multicall_entry entries[MC_BATCH];
+ u64 args[MC_ARGS];
+ unsigned mcidx, argidx;
+};
+
+static DEFINE_PER_CPU(struct mc_buffer, mc_buffer);
+DEFINE_PER_CPU(unsigned long, xen_mc_irq_flags);
+
+void xen_mc_flush(void)
+{
+ struct mc_buffer *b = &get_cpu_var(mc_buffer);
+ int ret = 0;
+ unsigned long flags;
+
+ /* Disable interrupts in case someone comes in and queues
+ something in the middle */
+ local_irq_save(flags);
+
+ if (b->mcidx) {
+ int i;
+
+ if (HYPERVISOR_multicall(b->entries, b->mcidx) != 0)
+ BUG();
+ for (i = 0; i < b->mcidx; i++)
+ if (b->entries[i].result < 0)
+ ret++;
+ b->mcidx = 0;
+ b->argidx = 0;
+ } else
+ BUG_ON(b->argidx != 0);
+
+ put_cpu_var(mc_buffer);
+ local_irq_restore(flags);
+
+ BUG_ON(ret);
+}
+
+struct multicall_space __xen_mc_entry(size_t args)
+{
+ struct mc_buffer *b = &get_cpu_var(mc_buffer);
+ struct multicall_space ret;
+ unsigned argspace = (args + sizeof(u64) - 1) / sizeof(u64);
+
+ BUG_ON(argspace > MC_ARGS);
+
+ if (b->mcidx == MC_BATCH ||
+ (b->argidx + argspace) > MC_ARGS)
+ xen_mc_flush();
+
+ ret.mc = &b->entries[b->mcidx];
+ b->mcidx++;
+ ret.args = &b->args[b->argidx];
+ b->argidx += argspace;
+
+ put_cpu_var(mc_buffer);
+
+ return ret;
+}
diff --git a/arch/i386/xen/multicalls.h b/arch/i386/xen/multicalls.h
new file mode 100644
index 00000000000..e6f7530b156
--- /dev/null
+++ b/arch/i386/xen/multicalls.h
@@ -0,0 +1,45 @@
+#ifndef _XEN_MULTICALLS_H
+#define _XEN_MULTICALLS_H
+
+#include "xen-ops.h"
+
+/* Multicalls */
+struct multicall_space
+{
+ struct multicall_entry *mc;
+ void *args;
+};
+
+/* Allocate room for a multicall and its args */
+struct multicall_space __xen_mc_entry(size_t args);
+
+DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags);
+
+/* Call to start a batch of multiple __xen_mc_entry()s. Must be
+ paired with xen_mc_issue() */
+static inline void xen_mc_batch(void)
+{
+ /* need to disable interrupts until this entry is complete */
+ local_irq_save(__get_cpu_var(xen_mc_irq_flags));
+}
+
+static inline struct multicall_space xen_mc_entry(size_t args)
+{
+ xen_mc_batch();
+ return __xen_mc_entry(args);
+}
+
+/* Flush all pending multicalls */
+void xen_mc_flush(void);
+
+/* Issue a multicall if we're not in a lazy mode */
+static inline void xen_mc_issue(unsigned mode)
+{
+ if ((xen_get_lazy_mode() & mode) == 0)
+ xen_mc_flush();
+
+ /* restore flags saved in xen_mc_batch */
+ local_irq_restore(x86_read_percpu(xen_mc_irq_flags));
+}
+
+#endif /* _XEN_MULTICALLS_H */
diff --git a/arch/i386/xen/setup.c b/arch/i386/xen/setup.c
new file mode 100644
index 00000000000..7da93ee612f
--- /dev/null
+++ b/arch/i386/xen/setup.c
@@ -0,0 +1,97 @@
+/*
+ * Machine specific setup for xen
+ *
+ * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/pm.h>
+
+#include <asm/elf.h>
+#include <asm/e820.h>
+#include <asm/setup.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/interface/physdev.h>
+#include <xen/features.h>
+
+#include "xen-ops.h"
+
+/* These are code, but not functions. Defined in entry.S */
+extern const char xen_hypervisor_callback[];
+extern const char xen_failsafe_callback[];
+
+static __initdata struct shared_info init_shared;
+
+/*
+ * 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 = &init_shared;
+
+unsigned long *phys_to_machine_mapping;
+EXPORT_SYMBOL(phys_to_machine_mapping);
+
+/**
+ * machine_specific_memory_setup - Hook for machine specific memory setup.
+ **/
+
+char * __init xen_memory_setup(void)
+{
+ unsigned long max_pfn = xen_start_info->nr_pages;
+
+ e820.nr_map = 0;
+ add_memory_region(0, PFN_PHYS(max_pfn), E820_RAM);
+
+ return "Xen";
+}
+
+static void xen_idle(void)
+{
+ local_irq_disable();
+
+ if (need_resched())
+ local_irq_enable();
+ else {
+ current_thread_info()->status &= ~TS_POLLING;
+ smp_mb__after_clear_bit();
+ safe_halt();
+ current_thread_info()->status |= TS_POLLING;
+ }
+}
+
+void __init xen_arch_setup(void)
+{
+ struct physdev_set_iopl set_iopl;
+ int rc;
+
+ HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
+ HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
+
+ if (!xen_feature(XENFEAT_auto_translated_physmap))
+ HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
+
+ HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
+ __KERNEL_CS, (unsigned long)xen_failsafe_callback);
+
+ set_iopl.iopl = 1;
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
+ if (rc != 0)
+ printk(KERN_INFO "physdev_op failed %d\n", rc);
+
+#ifdef CONFIG_ACPI
+ if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
+ printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
+ disable_acpi();
+ }
+#endif
+
+ memcpy(boot_command_line, xen_start_info->cmd_line,
+ MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
+ COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
+
+ pm_idle = xen_idle;
+}
diff --git a/arch/i386/xen/xen-head.S b/arch/i386/xen/xen-head.S
new file mode 100644
index 00000000000..2998d55a001
--- /dev/null
+++ b/arch/i386/xen/xen-head.S
@@ -0,0 +1,36 @@
+/* Xen-specific pieces of head.S, intended to be included in the right
+ place in head.S */
+
+#ifdef CONFIG_XEN
+
+#include <linux/elfnote.h>
+#include <asm/boot.h>
+#include <xen/interface/elfnote.h>
+
+ENTRY(startup_xen)
+ movl %esi,xen_start_info
+ cld
+ movl $(init_thread_union+THREAD_SIZE),%esp
+ jmp xen_start_kernel
+
+.pushsection ".bss.page_aligned"
+ .align PAGE_SIZE_asm
+ENTRY(hypercall_page)
+ .skip 0x1000
+.popsection
+
+ ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux")
+ ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6")
+ ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0")
+ ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, .long __PAGE_OFFSET)
+ ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, .long startup_xen)
+ ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .long hypercall_page)
+ ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .asciz "!writable_page_tables|pae_pgdir_above_4gb")
+#ifdef CONFIG_X86_PAE
+ ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes")
+#else
+ ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "no")
+#endif
+ ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic")
+
+#endif /*CONFIG_XEN */
diff --git a/arch/i386/xen/xen-ops.h b/arch/i386/xen/xen-ops.h
new file mode 100644
index 00000000000..79648fe1ab7
--- /dev/null
+++ b/arch/i386/xen/xen-ops.h
@@ -0,0 +1,31 @@
+#ifndef XEN_OPS_H
+#define XEN_OPS_H
+
+#include <linux/init.h>
+#include <linux/clocksource.h>
+
+DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu);
+DECLARE_PER_CPU(unsigned long, xen_cr3);
+
+extern struct start_info *xen_start_info;
+extern struct shared_info *HYPERVISOR_shared_info;
+
+char * __init xen_memory_setup(void);
+void __init xen_arch_setup(void);
+void __init xen_init_IRQ(void);
+
+unsigned long xen_cpu_khz(void);
+void __init xen_time_init(void);
+unsigned long xen_get_wallclock(void);
+int xen_set_wallclock(unsigned long time);
+cycle_t xen_clocksource_read(void);
+
+DECLARE_PER_CPU(enum paravirt_lazy_mode, xen_lazy_mode);
+
+static inline unsigned xen_get_lazy_mode(void)
+{
+ return x86_read_percpu(xen_lazy_mode);
+}
+
+
+#endif /* XEN_OPS_H */