| Message ID | 20220114203145.242984-23-mjrosato@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: s390: enable zPCI for interpretive execution | expand |
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 <mjrosato@linux.ibm.com> > --- > 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; > } >
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 <mjrosato@linux.ibm.com> >> --- >> 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 <mjrosato@linux.ibm.com> >>> --- >>> 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; >>> } >>> >> >
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 <mjrosato@linux.ibm.com> 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; > } >
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; }
For faster handling of PCI translation refreshes, intercept in KVM and call the associated handler. Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> --- arch/s390/kvm/priv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+)