Commit 43656f77 authored by Claudio Imbrenda's avatar Claudio Imbrenda
Browse files

KVM: s390: move gmap_shadow_pgt_lookup() into kvm 



Move gmap_shadow_pgt_lookup() from mm/gmap.c into kvm/gaccess.c .

Reviewed-by: default avatarSteffen Eiden <seiden@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: default avatarChristoph Schlameuss <schlameuss@linux.ibm.com>
Link: https://lore.kernel.org/r/20250123144627.312456-13-imbrenda@linux.ibm.com


Signed-off-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-13-imbrenda@linux.ibm.com>
parent ef0c8ef8

arch/s390/include/asm/gmap.h

+1 −2
Original line number Diff line number Diff line
@@ -125,8 +125,6 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, 
		    int fake);

int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,

		    int fake);

int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,

			   unsigned long *pgt, int *dat_protection, int *fake);

int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte);



void gmap_register_pte_notifier(struct gmap_notifier *);
@@ -142,6 +140,7 @@ void s390_uv_destroy_pfns(unsigned long count, unsigned long *pfns); 
int __s390_uv_destroy_range(struct mm_struct *mm, unsigned long start,

			    unsigned long end, bool interruptible);

int kvm_s390_wiggle_split_folio(struct mm_struct *mm, struct folio *folio, bool split);

unsigned long *gmap_table_walk(struct gmap *gmap, unsigned long gaddr, int level);



/**

 * s390_uv_destroy_range - Destroy a range of pages in the given mm.

arch/s390/kvm/gaccess.c

+41 −1
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <asm/gmap.h>

#include <asm/dat-bits.h>

#include "kvm-s390.h"

#include "gmap.h"

#include "gaccess.h"



/*
@@ -1392,6 +1393,42 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr, 
	return 0;

}



/**

 * shadow_pgt_lookup() - find a shadow page table

 * @sg: pointer to the shadow guest address space structure

 * @saddr: the address in the shadow aguest address space

 * @pgt: parent gmap address of the page table to get shadowed

 * @dat_protection: if the pgtable is marked as protected by dat

 * @fake: pgt references contiguous guest memory block, not a pgtable

 *

 * Returns 0 if the shadow page table was found and -EAGAIN if the page

 * table was not found.

 *

 * Called with sg->mm->mmap_lock in read.

 */

static int shadow_pgt_lookup(struct gmap *sg, unsigned long saddr, unsigned long *pgt,

			     int *dat_protection, int *fake)

{

	unsigned long *table;

	struct page *page;

	int rc;



	spin_lock(&sg->guest_table_lock);

	table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */

	if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {

		/* Shadow page tables are full pages (pte+pgste) */

		page = pfn_to_page(*table >> PAGE_SHIFT);

		*pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE;

		*dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);

		*fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE);

		rc = 0;

	} else  {

		rc = -EAGAIN;

	}

	spin_unlock(&sg->guest_table_lock);

	return rc;

}



/**

 * kvm_s390_shadow_fault - handle fault on a shadow page table

 * @vcpu: virtual cpu
@@ -1415,6 +1452,9 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg, 
	int dat_protection, fake;

	int rc;



	if (KVM_BUG_ON(!gmap_is_shadow(sg), vcpu->kvm))

		return -EFAULT;



	mmap_read_lock(sg->mm);

	/*

	 * We don't want any guest-2 tables to change - so the parent
@@ -1423,7 +1463,7 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg, 
	 */

	ipte_lock(vcpu->kvm);



	rc = gmap_shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection, &fake);

	rc = shadow_pgt_lookup(sg, saddr, &pgt, &dat_protection, &fake);

	if (rc)

		rc = kvm_s390_shadow_tables(sg, saddr, &pgt, &dat_protection,

					    &fake);

arch/s390/kvm/gmap.h

+2 −0
Original line number Diff line number Diff line
@@ -10,6 +10,8 @@ 
#ifndef ARCH_KVM_S390_GMAP_H

#define ARCH_KVM_S390_GMAP_H



#define GMAP_SHADOW_FAKE_TABLE 1ULL



int gmap_make_secure(struct gmap *gmap, unsigned long gaddr, void *uvcb);

int gmap_convert_to_secure(struct gmap *gmap, unsigned long gaddr);

int gmap_destroy_page(struct gmap *gmap, unsigned long gaddr);

arch/s390/mm/gmap.c

+2 −44
Original line number Diff line number Diff line
@@ -36,8 +36,6 @@ 


#define GMAP_SHADOW_FAKE_TABLE 1ULL



static inline unsigned long *gmap_table_walk(struct gmap *gmap, unsigned long gaddr, int level);



static struct page *gmap_alloc_crst(void)

{

	struct page *page;
@@ -738,8 +736,7 @@ static void gmap_call_notifier(struct gmap *gmap, unsigned long start, 
 *

 * Note: Can also be called for shadow gmaps.

 */

static inline unsigned long *gmap_table_walk(struct gmap *gmap,

					     unsigned long gaddr, int level)

unsigned long *gmap_table_walk(struct gmap *gmap, unsigned long gaddr, int level)

{

	const int asce_type = gmap->asce & _ASCE_TYPE_MASK;

	unsigned long *table = gmap->table;
@@ -790,6 +787,7 @@ static inline unsigned long *gmap_table_walk(struct gmap *gmap, 
	}

	return table;

}

EXPORT_SYMBOL(gmap_table_walk);



/**

 * gmap_pte_op_walk - walk the gmap page table, get the page table lock
@@ -1744,46 +1742,6 @@ int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, 
}

EXPORT_SYMBOL_GPL(gmap_shadow_sgt);



/**

 * gmap_shadow_pgt_lookup - find a shadow page table

 * @sg: pointer to the shadow guest address space structure

 * @saddr: the address in the shadow aguest address space

 * @pgt: parent gmap address of the page table to get shadowed

 * @dat_protection: if the pgtable is marked as protected by dat

 * @fake: pgt references contiguous guest memory block, not a pgtable

 *

 * Returns 0 if the shadow page table was found and -EAGAIN if the page

 * table was not found.

 *

 * Called with sg->mm->mmap_lock in read.

 */

int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,

			   unsigned long *pgt, int *dat_protection,

			   int *fake)

{

	unsigned long *table;

	struct page *page;

	int rc;



	BUG_ON(!gmap_is_shadow(sg));

	spin_lock(&sg->guest_table_lock);

	table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */

	if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {

		/* Shadow page tables are full pages (pte+pgste) */

		page = pfn_to_page(*table >> PAGE_SHIFT);

		*pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE;

		*dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);

		*fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE);

		rc = 0;

	} else  {

		rc = -EAGAIN;

	}

	spin_unlock(&sg->guest_table_lock);

	return rc;



}

EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);



/**

 * gmap_shadow_pgt - instantiate a shadow page table

 * @sg: pointer to the shadow guest address space structure