x86: Call HVMOP_pagetable_dying on exit_mmap.

When a pagetable is about to be destroyed, we notify Xen so that the
hypervisor can clear the related shadow pagetable.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This commit is contained in:
Stefano Stabellini 2010-06-17 14:22:52 +01:00 committed by Jeremy Fitzhardinge
parent c1c5413ad5
commit 5915100106
4 changed files with 46 additions and 0 deletions

View file

@ -1318,6 +1318,7 @@ static void __init xen_hvm_guest_init(void)
have_vcpu_info_placement = 0;
x86_init.irqs.intr_init = xen_init_IRQ;
xen_hvm_init_time_ops();
xen_hvm_init_mmu_ops();
}
static bool __init xen_hvm_platform(void)

View file

@ -58,6 +58,7 @@
#include <xen/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/hvm/hvm_op.h>
#include <xen/interface/version.h>
#include <xen/hvc-console.h>
@ -1941,6 +1942,38 @@ void __init xen_init_mmu_ops(void)
pv_mmu_ops = xen_mmu_ops;
}
static void xen_hvm_exit_mmap(struct mm_struct *mm)
{
struct xen_hvm_pagetable_dying a;
int rc;
a.domid = DOMID_SELF;
a.gpa = __pa(mm->pgd);
rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
WARN_ON_ONCE(rc < 0);
}
static int is_pagetable_dying_supported(void)
{
struct xen_hvm_pagetable_dying a;
int rc = 0;
a.domid = DOMID_SELF;
a.gpa = 0x00;
rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
if (rc < 0) {
printk(KERN_DEBUG "HVMOP_pagetable_dying not supported\n");
return 0;
}
return 1;
}
void __init xen_hvm_init_mmu_ops(void)
{
if (is_pagetable_dying_supported())
pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap;
}
#ifdef CONFIG_XEN_DEBUG_FS
static struct dentry *d_mmu_debug;

View file

@ -60,4 +60,5 @@ void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
unsigned long xen_read_cr2_direct(void);
extern void xen_init_mmu_ops(void);
extern void xen_hvm_init_mmu_ops(void);
#endif /* _XEN_MMU_H */

View file

@ -32,4 +32,15 @@ struct xen_hvm_param {
};
DEFINE_GUEST_HANDLE_STRUCT(xen_hvm_param);
/* Hint from PV drivers for pagetable destruction. */
#define HVMOP_pagetable_dying 9
struct xen_hvm_pagetable_dying {
/* Domain with a pagetable about to be destroyed. */
domid_t domid;
/* guest physical address of the toplevel pagetable dying */
aligned_u64 gpa;
};
typedef struct xen_hvm_pagetable_dying xen_hvm_pagetable_dying_t;
DEFINE_GUEST_HANDLE_STRUCT(xen_hvm_pagetable_dying_t);
#endif /* __XEN_PUBLIC_HVM_HVM_OP_H__ */