Commit 55531b74 authored by Janosch Frank's avatar Janosch Frank Committed by Christian Borntraeger
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KVM: s390: Add storage key facility interpretation control 



Up to now we always expected to have the storage key facility
available for our (non-VSIE) KVM guests. For huge page support, we
need to be able to disable it, so let's introduce that now.

We add the use_skf variable to manage KVM storage key facility
usage. Also we rename use_skey in the mm context struct to uses_skeys
to make it more clear that it is an indication that the vm actively
uses storage keys.

Signed-off-by: default avatarJanosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: default avatarFarhan Ali <alifm@linux.vnet.ibm.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Acked-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
parent 75bc37fe

arch/s390/include/asm/kvm_host.h

+1 −0
Original line number Diff line number Diff line
@@ -812,6 +812,7 @@ struct kvm_arch{ 
	int use_irqchip;

	int use_cmma;

	int use_pfmfi;

	int use_skf;

	int user_cpu_state_ctrl;

	int user_sigp;

	int user_stsi;

arch/s390/include/asm/mmu.h

+1 −1
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ typedef struct { 
	/* The mmu context uses extended page tables. */

	unsigned int has_pgste:1;

	/* The mmu context uses storage keys. */

	unsigned int use_skey:1;

	unsigned int uses_skeys:1;

	/* The mmu context uses CMM. */

	unsigned int uses_cmm:1;

} mm_context_t;

arch/s390/include/asm/mmu_context.h

+1 −1
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ static inline int init_new_context(struct task_struct *tsk, 
		test_thread_flag(TIF_PGSTE) ||

		(current->mm && current->mm->context.alloc_pgste);

	mm->context.has_pgste = 0;

	mm->context.use_skey = 0;

	mm->context.uses_skeys = 0;

	mm->context.uses_cmm = 0;

#endif

	switch (mm->context.asce_limit) {

arch/s390/include/asm/pgtable.h

+2 −2
Original line number Diff line number Diff line
@@ -507,10 +507,10 @@ static inline int mm_alloc_pgste(struct mm_struct *mm) 
 * faults should no longer be backed by zero pages

 */

#define mm_forbids_zeropage mm_has_pgste

static inline int mm_use_skey(struct mm_struct *mm)

static inline int mm_uses_skeys(struct mm_struct *mm)

{

#ifdef CONFIG_PGSTE

	if (mm->context.use_skey)

	if (mm->context.uses_skeys)

		return 1;

#endif

	return 0;

arch/s390/kvm/kvm-s390.c

+2 −1
Original line number Diff line number Diff line
@@ -1493,7 +1493,7 @@ static long kvm_s390_get_skeys(struct kvm *kvm, struct kvm_s390_skeys *args) 
		return -EINVAL;



	/* Is this guest using storage keys? */

	if (!mm_use_skey(current->mm))

	if (!mm_uses_skeys(current->mm))

		return KVM_S390_GET_SKEYS_NONE;



	/* Enforce sane limit on memory allocation */
@@ -2066,6 +2066,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) 
	kvm->arch.css_support = 0;

	kvm->arch.use_irqchip = 0;

	kvm->arch.use_pfmfi = sclp.has_pfmfi;

	kvm->arch.use_skf = sclp.has_skey;

	kvm->arch.epoch = 0;



	spin_lock_init(&kvm->arch.start_stop_lock);

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