For faster handling of PCI translation refreshes, intercept in KVM
and call the associated handler.
Signed-off-by: Matthew Rosato <[email protected]>
---
arch/s390/kvm/priv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 417154b314a6..5b65c1830de2 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -29,6 +29,7 @@
#include <asm/ap.h>
#include "gaccess.h"
#include "kvm-s390.h"
+#include "pci.h"
#include "trace.h"
static int handle_ri(struct kvm_vcpu *vcpu)
@@ -335,6 +336,49 @@ static int handle_rrbe(struct kvm_vcpu *vcpu)
return 0;
}
+static int handle_rpcit(struct kvm_vcpu *vcpu)
+{
+ int reg1, reg2;
+ u8 status;
+ int rc;
+
+ if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
+ return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
+
+ /* If the host doesn't support PCI, it must be an emulated device */
+ if (!IS_ENABLED(CONFIG_PCI))
+ return -EOPNOTSUPP;
+
+ kvm_s390_get_regs_rre(vcpu, ®1, ®2);
+
+ /* If the device has a SHM bit on, let userspace take care of this */
+ if (((vcpu->run->s.regs.gprs[reg1] >> 32) & aift->mdd) != 0)
+ return -EOPNOTSUPP;
+
+ rc = kvm_s390_pci_refresh_trans(vcpu, vcpu->run->s.regs.gprs[reg1],
+ vcpu->run->s.regs.gprs[reg2],
+ vcpu->run->s.regs.gprs[reg2+1],
+ &status);
+
+ switch (rc) {
+ case 0:
+ kvm_s390_set_psw_cc(vcpu, 0);
+ break;
+ case -EOPNOTSUPP:
+ return -EOPNOTSUPP;
+ default:
+ vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00ffffffUL;
+ vcpu->run->s.regs.gprs[reg1] |= (u64) status << 24;
+ if (status != 0)
+ kvm_s390_set_psw_cc(vcpu, 1);
+ else
+ kvm_s390_set_psw_cc(vcpu, 3);
+ break;
+ }
+
+ return 0;
+}
+
#define SSKE_NQ 0x8
#define SSKE_MR 0x4
#define SSKE_MC 0x2
@@ -1275,6 +1319,8 @@ int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
return handle_essa(vcpu);
case 0xaf:
return handle_pfmf(vcpu);
+ case 0xd3:
+ return handle_rpcit(vcpu);
default:
return -EOPNOTSUPP;
}
--
2.27.0
On 1/14/22 21:31, Matthew Rosato wrote:
> For faster handling of PCI translation refreshes, intercept in KVM
> and call the associated handler.
>
> Signed-off-by: Matthew Rosato <[email protected]>
> ---
> arch/s390/kvm/priv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 46 insertions(+)
>
> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
> index 417154b314a6..5b65c1830de2 100644
> --- a/arch/s390/kvm/priv.c
> +++ b/arch/s390/kvm/priv.c
> @@ -29,6 +29,7 @@
> #include <asm/ap.h>
> #include "gaccess.h"
> #include "kvm-s390.h"
> +#include "pci.h"
> #include "trace.h"
>
> static int handle_ri(struct kvm_vcpu *vcpu)
> @@ -335,6 +336,49 @@ static int handle_rrbe(struct kvm_vcpu *vcpu)
> return 0;
> }
>
> +static int handle_rpcit(struct kvm_vcpu *vcpu)
> +{
> + int reg1, reg2;
> + u8 status;
> + int rc;
> +
> + if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
> + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
> +
> + /* If the host doesn't support PCI, it must be an emulated device */
> + if (!IS_ENABLED(CONFIG_PCI))
> + return -EOPNOTSUPP;
AFAIU this makes also sure that the following code is not compiled in
case PCI is not supported.
I am not very used to compilation options, is it true with all our
compilers and options?
Or do we have to specify a compiler version?
Another concern is, shouldn't we use IS_ENABLED(CONFIG_VFIO_PCI) ?
> +
> + kvm_s390_get_regs_rre(vcpu, ®1, ®2);
> +
> + /* If the device has a SHM bit on, let userspace take care of this */
> + if (((vcpu->run->s.regs.gprs[reg1] >> 32) & aift->mdd) != 0)
> + return -EOPNOTSUPP;
> +
> + rc = kvm_s390_pci_refresh_trans(vcpu, vcpu->run->s.regs.gprs[reg1],
> + vcpu->run->s.regs.gprs[reg2],
> + vcpu->run->s.regs.gprs[reg2+1],
> + &status);
> +
> + switch (rc) {
> + case 0:
> + kvm_s390_set_psw_cc(vcpu, 0);
> + break;
> + case -EOPNOTSUPP:
> + return -EOPNOTSUPP;
> + default:
> + vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00ffffffUL;
> + vcpu->run->s.regs.gprs[reg1] |= (u64) status << 24;
> + if (status != 0)
> + kvm_s390_set_psw_cc(vcpu, 1);
> + else
> + kvm_s390_set_psw_cc(vcpu, 3);
> + break;
> + }
> +
> + return 0;
> +}
> +
> #define SSKE_NQ 0x8
> #define SSKE_MR 0x4
> #define SSKE_MC 0x2
> @@ -1275,6 +1319,8 @@ int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
> return handle_essa(vcpu);
> case 0xaf:
> return handle_pfmf(vcpu);
> + case 0xd3:
> + return handle_rpcit(vcpu);
> default:
> return -EOPNOTSUPP;
> }
>
--
Pierre Morel
IBM Lab Boeblingen
On 1/18/22 6:05 AM, Pierre Morel wrote:
>
>
> On 1/14/22 21:31, Matthew Rosato wrote:
>> For faster handling of PCI translation refreshes, intercept in KVM
>> and call the associated handler.
>>
>> Signed-off-by: Matthew Rosato <[email protected]>
>> ---
>> arch/s390/kvm/priv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 46 insertions(+)
>>
>> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
>> index 417154b314a6..5b65c1830de2 100644
>> --- a/arch/s390/kvm/priv.c
>> +++ b/arch/s390/kvm/priv.c
>> @@ -29,6 +29,7 @@
>> #include <asm/ap.h>
>> #include "gaccess.h"
>> #include "kvm-s390.h"
>> +#include "pci.h"
>> #include "trace.h"
>> static int handle_ri(struct kvm_vcpu *vcpu)
>> @@ -335,6 +336,49 @@ static int handle_rrbe(struct kvm_vcpu *vcpu)
>> return 0;
>> }
>> +static int handle_rpcit(struct kvm_vcpu *vcpu)
>> +{
>> + int reg1, reg2;
>> + u8 status;
>> + int rc;
>> +
>> + if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
>> + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
>> +
>> + /* If the host doesn't support PCI, it must be an emulated device */
>> + if (!IS_ENABLED(CONFIG_PCI))
>> + return -EOPNOTSUPP;
>
> AFAIU this makes also sure that the following code is not compiled in
> case PCI is not supported.
>
> I am not very used to compilation options, is it true with all our
> compilers and options?
> Or do we have to specify a compiler version?
>
> Another concern is, shouldn't we use IS_ENABLED(CONFIG_VFIO_PCI) ?
Same idea as in the other thread -- What we are trying to protect
against here is referencing symbols that won't be linked (like
zpci_refresh_trans, or the aift->mdd a few lines below)
It is indeed true that we should never need to handle the rpcit
intercept in KVM if CONFIG_VFIO_PCI=n -- but the necessary symbols/code
are linked at least, so we can just let the SHM logic sort this out.
When CONFIG_PCI=y|m, arch/s390/kvm/pci.o will be linked and so we can
compare the function handle against afit->mdd (check to see if the
device is emulated) and use this to determine whether or not to
immediately send to userspace -- And if CONFIG_VFIO_PCI=n, a SHM bit
will always be on and so we'll always go to userspace via this check.
>
>
>
>> +
>> + kvm_s390_get_regs_rre(vcpu, ®1, ®2);
>> +
>> + /* If the device has a SHM bit on, let userspace take care of
>> this */
>> + if (((vcpu->run->s.regs.gprs[reg1] >> 32) & aift->mdd) != 0)
>> + return -EOPNOTSUPP;
>> +
>> + rc = kvm_s390_pci_refresh_trans(vcpu, vcpu->run->s.regs.gprs[reg1],
>> + vcpu->run->s.regs.gprs[reg2],
>> + vcpu->run->s.regs.gprs[reg2+1],
>> + &status);
>> +
>> + switch (rc) {
>> + case 0:
>> + kvm_s390_set_psw_cc(vcpu, 0);
>> + break;
>> + case -EOPNOTSUPP:
>> + return -EOPNOTSUPP;
>> + default:
>> + vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00ffffffUL;
>> + vcpu->run->s.regs.gprs[reg1] |= (u64) status << 24;
>> + if (status != 0)
>> + kvm_s390_set_psw_cc(vcpu, 1);
>> + else
>> + kvm_s390_set_psw_cc(vcpu, 3);
>> + break;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> #define SSKE_NQ 0x8
>> #define SSKE_MR 0x4
>> #define SSKE_MC 0x2
>> @@ -1275,6 +1319,8 @@ int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
>> return handle_essa(vcpu);
>> case 0xaf:
>> return handle_pfmf(vcpu);
>> + case 0xd3:
>> + return handle_rpcit(vcpu);
>> default:
>> return -EOPNOTSUPP;
>> }
>>
>
On 1/18/22 18:27, Matthew Rosato wrote:
> On 1/18/22 6:05 AM, Pierre Morel wrote:
>>
>>
>> On 1/14/22 21:31, Matthew Rosato wrote:
>>> For faster handling of PCI translation refreshes, intercept in KVM
>>> and call the associated handler.
>>>
>>> Signed-off-by: Matthew Rosato <[email protected]>
>>> ---
>>> arch/s390/kvm/priv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
>>> 1 file changed, 46 insertions(+)
>>>
>>> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
>>> index 417154b314a6..5b65c1830de2 100644
>>> --- a/arch/s390/kvm/priv.c
>>> +++ b/arch/s390/kvm/priv.c
>>> @@ -29,6 +29,7 @@
>>> #include <asm/ap.h>
>>> #include "gaccess.h"
>>> #include "kvm-s390.h"
>>> +#include "pci.h"
>>> #include "trace.h"
>>> static int handle_ri(struct kvm_vcpu *vcpu)
>>> @@ -335,6 +336,49 @@ static int handle_rrbe(struct kvm_vcpu *vcpu)
>>> return 0;
>>> }
>>> +static int handle_rpcit(struct kvm_vcpu *vcpu)
>>> +{
>>> + int reg1, reg2;
>>> + u8 status;
>>> + int rc;
>>> +
>>> + if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
>>> + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
>>> +
>>> + /* If the host doesn't support PCI, it must be an emulated
>>> device */
>>> + if (!IS_ENABLED(CONFIG_PCI))
>>> + return -EOPNOTSUPP;
>>
>> AFAIU this makes also sure that the following code is not compiled in
>> case PCI is not supported.
>>
>> I am not very used to compilation options, is it true with all our
>> compilers and options?
>> Or do we have to specify a compiler version?
>>
>> Another concern is, shouldn't we use IS_ENABLED(CONFIG_VFIO_PCI) ?
>
> Same idea as in the other thread -- What we are trying to protect
> against here is referencing symbols that won't be linked (like
> zpci_refresh_trans, or the aift->mdd a few lines below)
>
> It is indeed true that we should never need to handle the rpcit
> intercept in KVM if CONFIG_VFIO_PCI=n -- but the necessary symbols/code
> are linked at least, so we can just let the SHM logic sort this out.
> When CONFIG_PCI=y|m, arch/s390/kvm/pci.o will be linked and so we can
> compare the function handle against afit->mdd (check to see if the
> device is emulated) and use this to determine whether or not to
> immediately send to userspace -- And if CONFIG_VFIO_PCI=n, a SHM bit
> will always be on and so we'll always go to userspace via this check.
So we agree.
But as I I said somewhere else I wonder if CONFIG_VFIO_PCI_ZDEV would
not even be better here.
>
>>
>>
>>
>>> +
>>> + kvm_s390_get_regs_rre(vcpu, ®1, ®2);
>>> +
>>> + /* If the device has a SHM bit on, let userspace take care of
>>> this */
>>> + if (((vcpu->run->s.regs.gprs[reg1] >> 32) & aift->mdd) != 0)
>>> + return -EOPNOTSUPP;
>>> +
>>> + rc = kvm_s390_pci_refresh_trans(vcpu, vcpu->run->s.regs.gprs[reg1],
>>> + vcpu->run->s.regs.gprs[reg2],
>>> + vcpu->run->s.regs.gprs[reg2+1],
>>> + &status);
>>> +
>>> + switch (rc) {
>>> + case 0:
>>> + kvm_s390_set_psw_cc(vcpu, 0);
>>> + break;
>>> + case -EOPNOTSUPP:
>>> + return -EOPNOTSUPP;
>>> + default:
>>> + vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00ffffffUL;
>>> + vcpu->run->s.regs.gprs[reg1] |= (u64) status << 24;
>>> + if (status != 0)
>>> + kvm_s390_set_psw_cc(vcpu, 1);
>>> + else
>>> + kvm_s390_set_psw_cc(vcpu, 3);
>>> + break;
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> #define SSKE_NQ 0x8
>>> #define SSKE_MR 0x4
>>> #define SSKE_MC 0x2
>>> @@ -1275,6 +1319,8 @@ int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
>>> return handle_essa(vcpu);
>>> case 0xaf:
>>> return handle_pfmf(vcpu);
>>> + case 0xd3:
>>> + return handle_rpcit(vcpu);
>>> default:
>>> return -EOPNOTSUPP;
>>> }
>>>
>>
>
--
Pierre Morel
IBM Lab Boeblingen
On 1/14/22 21:31, Matthew Rosato wrote:
> For faster handling of PCI translation refreshes, intercept in KVM
> and call the associated handler.
>
> Signed-off-by: Matthew Rosato <[email protected]>
Aside our previous discussion, 2 small codingstyle to fix
> ---
> arch/s390/kvm/priv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 46 insertions(+)
>
> diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
> index 417154b314a6..5b65c1830de2 100644
> --- a/arch/s390/kvm/priv.c
> +++ b/arch/s390/kvm/priv.c
> @@ -29,6 +29,7 @@
> #include <asm/ap.h>
> #include "gaccess.h"
> #include "kvm-s390.h"
> +#include "pci.h"
> #include "trace.h"
>
> static int handle_ri(struct kvm_vcpu *vcpu)
> @@ -335,6 +336,49 @@ static int handle_rrbe(struct kvm_vcpu *vcpu)
> return 0;
> }
>
> +static int handle_rpcit(struct kvm_vcpu *vcpu)
> +{
> + int reg1, reg2;
> + u8 status;
> + int rc;
> +
> + if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
> + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
> +
> + /* If the host doesn't support PCI, it must be an emulated device */
> + if (!IS_ENABLED(CONFIG_PCI))
> + return -EOPNOTSUPP;
> +
> + kvm_s390_get_regs_rre(vcpu, ®1, ®2);
> +
> + /* If the device has a SHM bit on, let userspace take care of this */
> + if (((vcpu->run->s.regs.gprs[reg1] >> 32) & aift->mdd) != 0)
> + return -EOPNOTSUPP;
> +
> + rc = kvm_s390_pci_refresh_trans(vcpu, vcpu->run->s.regs.gprs[reg1],
> + vcpu->run->s.regs.gprs[reg2],
> + vcpu->run->s.regs.gprs[reg2+1],
Here, spaces around "+"
> + &status);
> +
> + switch (rc) {
> + case 0:
> + kvm_s390_set_psw_cc(vcpu, 0);
> + break;
> + case -EOPNOTSUPP:
> + return -EOPNOTSUPP;
> + default:
> + vcpu->run->s.regs.gprs[reg1] &= 0xffffffff00ffffffUL;
> + vcpu->run->s.regs.gprs[reg1] |= (u64) status << 24;
Here no blank after cast.
> + if (status != 0)
> + kvm_s390_set_psw_cc(vcpu, 1);
> + else
> + kvm_s390_set_psw_cc(vcpu, 3);
> + break;
> + }
> +
> + return 0;
> +}
> +
> #define SSKE_NQ 0x8
> #define SSKE_MR 0x4
> #define SSKE_MC 0x2
> @@ -1275,6 +1319,8 @@ int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
> return handle_essa(vcpu);
> case 0xaf:
> return handle_pfmf(vcpu);
> + case 0xd3:
> + return handle_rpcit(vcpu);
> default:
> return -EOPNOTSUPP;
> }
>
--
Pierre Morel
IBM Lab Boeblingen