On Tue, 11 Dec 2012 11:22:04 +0100 Alexander Graf <agraf@xxxxxxx> wrote: > > On 10.12.2012, at 11:09, Cornelia Huck wrote: > > > On Mon, 10 Dec 2012 08:33:10 +0100 > > Alexander Graf <agraf@xxxxxxx> wrote: > > > >> > >> On 07.12.2012, at 13:30, Cornelia Huck wrote: > >> > >>> Add support for handling I/O interrupts (standard, subchannel-related > >>> ones and rudimentary adapter interrupts). > >>> > >>> The subchannel-identifying parameters are encoded into the interrupt > >>> type. > >>> > >>> I/O interrupts are floating, so they can't be injected on a specific > >>> vcpu. > >>> > >>> Reviewed-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx> > >>> Signed-off-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> > >>> --- > >>> Documentation/virtual/kvm/api.txt | 4 ++ > >>> arch/s390/include/asm/kvm_host.h | 2 + > >>> arch/s390/kvm/interrupt.c | 115 ++++++++++++++++++++++++++++++++++++-- > >>> include/uapi/linux/kvm.h | 6 ++ > >>> 4 files changed, 122 insertions(+), 5 deletions(-) > >>> > >>> diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > >>> index 6671fdc..e298a72 100644 > >>> --- a/Documentation/virtual/kvm/api.txt > >>> +++ b/Documentation/virtual/kvm/api.txt > >>> @@ -2068,6 +2068,10 @@ KVM_S390_INT_VIRTIO (vm) - virtio external interrupt; external interrupt > >>> KVM_S390_INT_SERVICE (vm) - sclp external interrupt; sclp parameter in parm > >>> KVM_S390_INT_EMERGENCY (vcpu) - sigp emergency; source cpu in parm > >>> KVM_S390_INT_EXTERNAL_CALL (vcpu) - sigp external call; source cpu in parm > >>> +KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm) - compound value to indicate an > >>> + I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel); > >>> + I/O interruption parameters in parm (subchannel) and parm64 (intparm, > >>> + interruption subclass) > >>> > >>> Note that the vcpu ioctl is asynchronous to vcpu execution. > >>> > >>> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h > >>> index b784154..e47f697 100644 > >>> --- a/arch/s390/include/asm/kvm_host.h > >>> +++ b/arch/s390/include/asm/kvm_host.h > >>> @@ -76,6 +76,7 @@ struct kvm_s390_sie_block { > >>> __u64 epoch; /* 0x0038 */ > >>> __u8 reserved40[4]; /* 0x0040 */ > >>> #define LCTL_CR0 0x8000 > >>> +#define LCTL_CR6 0x0200 > >>> __u16 lctl; /* 0x0044 */ > >>> __s16 icpua; /* 0x0046 */ > >>> __u32 ictl; /* 0x0048 */ > >>> @@ -127,6 +128,7 @@ struct kvm_vcpu_stat { > >>> u32 deliver_prefix_signal; > >>> u32 deliver_restart_signal; > >>> u32 deliver_program_int; > >>> + u32 deliver_io_int; > >>> u32 exit_wait_state; > >>> u32 instruction_stidp; > >>> u32 instruction_spx; > >>> diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c > >>> index c30615e..070ba22 100644 > >>> --- a/arch/s390/kvm/interrupt.c > >>> +++ b/arch/s390/kvm/interrupt.c > >>> @@ -21,11 +21,26 @@ > >>> #include "gaccess.h" > >>> #include "trace-s390.h" > >>> > >>> +#define IOINT_SCHID_MASK 0x0000ffff > >>> +#define IOINT_SSID_MASK 0x00030000 > >>> +#define IOINT_CSSID_MASK 0x03fc0000 > >>> +#define IOINT_AI_MASK 0x04000000 > >>> + > >>> +static int is_ioint(u64 type) > >>> +{ > >>> + return ((type & 0xfffe0000u) != 0xfffe0000u); > >>> +} > >>> + > >>> static int psw_extint_disabled(struct kvm_vcpu *vcpu) > >>> { > >>> return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT); > >>> } > >>> > >>> +static int psw_ioint_disabled(struct kvm_vcpu *vcpu) > >>> +{ > >>> + return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO); > >>> +} > >>> + > >>> static int psw_interrupts_disabled(struct kvm_vcpu *vcpu) > >>> { > >>> if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) || > >>> @@ -68,7 +83,18 @@ static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu, > >>> case KVM_S390_RESTART: > >>> return 1; > >>> default: > >>> - BUG(); > >>> + if (is_ioint(inti->type)) { > >> > >> Though I usually like if (...) { positive) } else { abort(); } coding style in general, it makes code quite hard to read when you are limited to 80 characters per line :) > >> > >> I think it'd really help readability if you instead would write > >> > >> if (!is_ioint(...)) { > >> BUG(); > >> } > >> > >> and then continue without indent. That problem gets even more obvious further down the file. > > > > Hm, "bad state last" seems to parse, though. > > Fine with me. Extract the io bits into a separate function then :). Or maybe better even just use gcc switch magic: > > case 0x0 ... 0xfffdffff: What, magic numbers? ;) I'll check how this works out. Adding a #define for that range might even define better what INT_IO is. -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html