linux/arch/x86/xen/setup.c
Jeremy Fitzhardinge 6fcac6d305 xen64: set up syscall and sysenter entrypoints for 64-bit
We set up entrypoints for syscall and sysenter.  sysenter is only used
for 32-bit compat processes, whereas syscall can be used in by both 32
and 64-bit processes.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:05:52 +02:00

193 lines
4.5 KiB
C

/*
* 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/vdso.h>
#include <asm/e820.h>
#include <asm/setup.h>
#include <asm/acpi.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include <xen/page.h>
#include <xen/interface/callback.h>
#include <xen/interface/physdev.h>
#include <xen/features.h>
#include "xen-ops.h"
#include "vdso.h"
/* These are code, but not functions. Defined in entry.S */
extern const char xen_hypervisor_callback[];
extern const char xen_failsafe_callback[];
/**
* 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;
max_pfn = min(MAX_DOMAIN_PAGES, max_pfn);
e820.nr_map = 0;
e820_add_region(0, PFN_PHYS(max_pfn), E820_RAM);
/*
* Even though this is normal, usable memory under Xen, reserve
* ISA memory anyway because too many things think they can poke
* about in there.
*/
e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
E820_RESERVED);
/*
* Reserve Xen bits:
* - mfn_list
* - xen_start_info
* See comment above "struct start_info" in <xen/interface/xen.h>
*/
e820_add_region(__pa(xen_start_info->mfn_list),
xen_start_info->pt_base - xen_start_info->mfn_list,
E820_RESERVED);
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
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;
}
}
/*
* Set the bit indicating "nosegneg" library variants should be used.
*/
static void __init fiddle_vdso(void)
{
#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
extern const char vdso32_default_start;
u32 *mask = VDSO32_SYMBOL(&vdso32_default_start, NOTE_MASK);
*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
#endif
}
static __cpuinit int register_callback(unsigned type, const void *func)
{
struct callback_register callback = {
.type = type,
.address = XEN_CALLBACK(__KERNEL_CS, func),
.flags = CALLBACKF_mask_events,
};
return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
}
void __cpuinit xen_enable_sysenter(void)
{
int cpu = smp_processor_id();
extern void xen_sysenter_target(void);
int ret;
#ifdef CONFIG_X86_32
if (!boot_cpu_has(X86_FEATURE_SEP)) {
return;
}
#else
if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR) {
return;
}
#endif
ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
if(ret != 0) {
clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
}
}
void __cpuinit xen_enable_syscall(void)
{
#ifdef CONFIG_X86_64
int cpu = smp_processor_id();
int ret;
extern void xen_syscall_target(void);
extern void xen_syscall32_target(void);
ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
if (ret != 0) {
printk("failed to set syscall: %d\n", ret);
clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SYSCALL);
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SYSCALL);
} else {
ret = register_callback(CALLBACKTYPE_syscall32,
xen_syscall32_target);
if (ret != 0)
printk("failed to set 32-bit syscall: %d\n", ret);
}
#endif /* CONFIG_X86_64 */
}
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);
if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) ||
register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
BUG();
xen_enable_sysenter();
xen_enable_syscall();
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;
paravirt_disable_iospace();
fiddle_vdso();
}