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Commit 59151001 authored by Stefano Stabellini's avatar Stefano Stabellini Committed by Jeremy Fitzhardinge
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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: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
parent c1c5413a

arch/x86/xen/enlighten.c

+1 −0
Original line number Diff line number Diff line
@@ -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)

arch/x86/xen/mmu.c

+33 −0
Original line number Diff line number Diff line
@@ -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;

arch/x86/xen/mmu.h

+1 −0
Original line number Diff line number Diff line
@@ -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 */

include/xen/interface/hvm/hvm_op.h

+11 −0
Original line number Diff line number Diff line
@@ -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__ */