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Message-ID: <bd2910bb-957f-f095-8650-b192f9d6f10f@linux.ibm.com>
Date:   Mon, 7 Feb 2022 11:15:52 +0100
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Subject: Re: [PATCH v7 08/17] KVM: s390: pv: make kvm_s390_cpus_from_pv global
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To:     Claudio Imbrenda <imbrenda@linux.ibm.com>, kvm@vger.kernel.org
Cc:     borntraeger@de.ibm.com, thuth@redhat.com, pasic@linux.ibm.com,
        david@redhat.com, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org, scgl@linux.ibm.com
References: <20220204155349.63238-1-imbrenda@linux.ibm.com>
 <20220204155349.63238-9-imbrenda@linux.ibm.com>
From:   Janosch Frank <frankja@linux.ibm.com>
In-Reply-To: <20220204155349.63238-9-imbrenda@linux.ibm.com>
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On 2/4/22 16:53, Claudio Imbrenda wrote:
> The functions kvm_s390_cpus_from_pv needs to be called from pv.c, so
> make it global.


KVM: s390: pv: Add kvm_s390_cpus_from_pv to kvm-s390.h and provide 
documentation

Future changes make it necessary to call this function from pv.c.

While we're add it let's properly document kvm_s390_cpus_from_pv() and 
kvm_s390_cpus_to_pv().


Also could you swap patches 8 and 9 so this one is closer to patch #10?

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>

> 
> Take the opportunity to add documentation.
> 
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> ---
>   arch/s390/kvm/kvm-s390.c | 26 +++++++++++++++++++++++++-
>   arch/s390/kvm/kvm-s390.h |  1 +
>   2 files changed, 26 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 1a788f45d691..0fc8d1aec396 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -2175,7 +2175,20 @@ static int kvm_s390_set_cmma_bits(struct kvm *kvm,
>   	return r;
>   }
>   
> -static int kvm_s390_cpus_from_pv(struct kvm *kvm, u16 *rcp, u16 *rrcp)
> +/**
> + * kvm_s390_cpus_from_pv - Convert all protected vCPUs in a protected VM to
> + * non protected.
> + * @kvm the VM whose protected vCPUs are to be converted
> + * @rcp return value for the RC field of the UVC (in case of error)
> + * @rrcp return value for the RRC field of the UVC (in case of error)
> + *
> + * Does not stop in case of error, tries to convert as many
> + * CPUs as possible. In case of error, the RC and RRC of the last error are
> + * returned.
> + *
> + * Return: 0 in case of success, otherwise -EIO
> + */
> +int kvm_s390_cpus_from_pv(struct kvm *kvm, u16 *rcp, u16 *rrcp)
>   {
>   	struct kvm_vcpu *vcpu;
>   	u16 rc, rrc;
> @@ -2202,6 +2215,17 @@ static int kvm_s390_cpus_from_pv(struct kvm *kvm, u16 *rcp, u16 *rrcp)
>   	return ret;
>   }
>   
> +/**
> + * kvm_s390_cpus_to_pv - Convert all non-protected vCPUs in a protected VM
> + * to protected.
> + * @kvm the VM whose protected vCPUs are to be converted
> + * @rcp return value for the RC field of the UVC (in case of error)
> + * @rrcp return value for the RRC field of the UVC (in case of error)
> + *
> + * Tries to undo the conversion in case of error.
> + *
> + * Return: 0 in case of success, otherwise -EIO
> + */
>   static int kvm_s390_cpus_to_pv(struct kvm *kvm, u16 *rc, u16 *rrc)
>   {
>   	unsigned long i;
> diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
> index 098831e815e6..9276d910631b 100644
> --- a/arch/s390/kvm/kvm-s390.h
> +++ b/arch/s390/kvm/kvm-s390.h
> @@ -365,6 +365,7 @@ int kvm_s390_vcpu_setup_cmma(struct kvm_vcpu *vcpu);
>   void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu);
>   void kvm_s390_set_cpu_timer(struct kvm_vcpu *vcpu, __u64 cputm);
>   __u64 kvm_s390_get_cpu_timer(struct kvm_vcpu *vcpu);
> +int kvm_s390_cpus_from_pv(struct kvm *kvm, u16 *rcp, u16 *rrcp);
>   
>   /* implemented in diag.c */
>   int kvm_s390_handle_diag(struct kvm_vcpu *vcpu);
>