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author | Paolo Bonzini <pbonzini@redhat.com> | 2013-12-12 11:41:33 +0100 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2013-12-12 11:41:33 +0100 |
commit | 6bb05ef78553491b2e2e0710dde364331dc3cdd2 (patch) | |
tree | 02e15152f1fa25c21155d1e021d20972ac57ea36 | |
parent | 6dfacadd5858882eee1983995854d4e1fb1b966e (diff) | |
parent | ff1f3cb4b3ac5d039f02679f34cb1498d110d241 (diff) | |
download | op-kernel-dev-6bb05ef78553491b2e2e0710dde364331dc3cdd2.zip op-kernel-dev-6bb05ef78553491b2e2e0710dde364331dc3cdd2.tar.gz |
Merge tag 'kvm-s390-20131211' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next
Some further s390 patches for kvm-next.
Various improvements and bugfixes in the signal processor handling.
Document kvm support for diagnose (s390 hypercalls). And last but
not least, fix a bug in the s390 ioeventfd backend that was causing
us grief in scenarios with 4G+ memory.
-rw-r--r-- | Documentation/virtual/kvm/hypercalls.txt | 3 | ||||
-rw-r--r-- | Documentation/virtual/kvm/s390-diag.txt | 80 | ||||
-rw-r--r-- | arch/s390/include/asm/sigp.h | 2 | ||||
-rw-r--r-- | arch/s390/kvm/diag.c | 2 | ||||
-rw-r--r-- | arch/s390/kvm/sigp.c | 64 |
5 files changed, 139 insertions, 12 deletions
diff --git a/Documentation/virtual/kvm/hypercalls.txt b/Documentation/virtual/kvm/hypercalls.txt index 022198e..d922d73 100644 --- a/Documentation/virtual/kvm/hypercalls.txt +++ b/Documentation/virtual/kvm/hypercalls.txt @@ -17,6 +17,9 @@ S390: S390 uses diagnose instruction as hypercall (0x500) along with hypercall number in R1. + For further information on the S390 diagnose call as supported by KVM, + refer to Documentation/virtual/kvm/s390-diag.txt. + PowerPC: It uses R3-R10 and hypercall number in R11. R4-R11 are used as output registers. Return value is placed in R3. diff --git a/Documentation/virtual/kvm/s390-diag.txt b/Documentation/virtual/kvm/s390-diag.txt new file mode 100644 index 0000000..f1de4fb --- /dev/null +++ b/Documentation/virtual/kvm/s390-diag.txt @@ -0,0 +1,80 @@ +The s390 DIAGNOSE call on KVM +============================= + +KVM on s390 supports the DIAGNOSE call for making hypercalls, both for +native hypercalls and for selected hypercalls found on other s390 +hypervisors. + +Note that bits are numbered as by the usual s390 convention (most significant +bit on the left). + + +General remarks +--------------- + +DIAGNOSE calls by the guest cause a mandatory intercept. This implies +all supported DIAGNOSE calls need to be handled by either KVM or its +userspace. + +All DIAGNOSE calls supported by KVM use the RS-a format: + +-------------------------------------- +| '83' | R1 | R3 | B2 | D2 | +-------------------------------------- +0 8 12 16 20 31 + +The second-operand address (obtained by the base/displacement calculation) +is not used to address data. Instead, bits 48-63 of this address specify +the function code, and bits 0-47 are ignored. + +The supported DIAGNOSE function codes vary by the userspace used. For +DIAGNOSE function codes not specific to KVM, please refer to the +documentation for the s390 hypervisors defining them. + + +DIAGNOSE function code 'X'500' - KVM virtio functions +----------------------------------------------------- + +If the function code specifies 0x500, various virtio-related functions +are performed. + +General register 1 contains the virtio subfunction code. Supported +virtio subfunctions depend on KVM's userspace. Generally, userspace +provides either s390-virtio (subcodes 0-2) or virtio-ccw (subcode 3). + +Upon completion of the DIAGNOSE instruction, general register 2 contains +the function's return code, which is either a return code or a subcode +specific value. + +Subcode 0 - s390-virtio notification and early console printk + Handled by userspace. + +Subcode 1 - s390-virtio reset + Handled by userspace. + +Subcode 2 - s390-virtio set status + Handled by userspace. + +Subcode 3 - virtio-ccw notification + Handled by either userspace or KVM (ioeventfd case). + + General register 2 contains a subchannel-identification word denoting + the subchannel of the virtio-ccw proxy device to be notified. + + General register 3 contains the number of the virtqueue to be notified. + + General register 4 contains a 64bit identifier for KVM usage (the + kvm_io_bus cookie). If general register 4 does not contain a valid + identifier, it is ignored. + + After completion of the DIAGNOSE call, general register 2 may contain + a 64bit identifier (in the kvm_io_bus cookie case). + + See also the virtio standard for a discussion of this hypercall. + + +DIAGNOSE function code 'X'501 - KVM breakpoint +---------------------------------------------- + +If the function code specifies 0x501, breakpoint functions may be performed. +This function code is handled by userspace. diff --git a/arch/s390/include/asm/sigp.h b/arch/s390/include/asm/sigp.h index 5a87d16..d091aa1 100644 --- a/arch/s390/include/asm/sigp.h +++ b/arch/s390/include/asm/sigp.h @@ -5,6 +5,7 @@ #define SIGP_SENSE 1 #define SIGP_EXTERNAL_CALL 2 #define SIGP_EMERGENCY_SIGNAL 3 +#define SIGP_START 4 #define SIGP_STOP 5 #define SIGP_RESTART 6 #define SIGP_STOP_AND_STORE_STATUS 9 @@ -12,6 +13,7 @@ #define SIGP_SET_PREFIX 13 #define SIGP_STORE_STATUS_AT_ADDRESS 14 #define SIGP_SET_ARCHITECTURE 18 +#define SIGP_COND_EMERGENCY_SIGNAL 19 #define SIGP_SENSE_RUNNING 21 /* SIGP condition codes */ diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c index 5ff29be..8216c0e 100644 --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -121,7 +121,7 @@ static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu) * - gpr 4 contains the index on the bus (optionally) */ ret = kvm_io_bus_write_cookie(vcpu->kvm, KVM_VIRTIO_CCW_NOTIFY_BUS, - vcpu->run->s.regs.gprs[2], + vcpu->run->s.regs.gprs[2] & 0xffffffff, 8, &vcpu->run->s.regs.gprs[3], vcpu->run->s.regs.gprs[4]); diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c index c370058..87c2b3a 100644 --- a/arch/s390/kvm/sigp.c +++ b/arch/s390/kvm/sigp.c @@ -1,7 +1,7 @@ /* * handling interprocessor communication * - * Copyright IBM Corp. 2008, 2009 + * Copyright IBM Corp. 2008, 2013 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License (version 2 only) @@ -89,6 +89,37 @@ unlock: return rc; } +static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr, + u16 asn, u64 *reg) +{ + struct kvm_vcpu *dst_vcpu = NULL; + const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT; + u16 p_asn, s_asn; + psw_t *psw; + u32 flags; + + if (cpu_addr < KVM_MAX_VCPUS) + dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr); + if (!dst_vcpu) + return SIGP_CC_NOT_OPERATIONAL; + flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags); + psw = &dst_vcpu->arch.sie_block->gpsw; + p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */ + s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */ + + /* Deliver the emergency signal? */ + if (!(flags & CPUSTAT_STOPPED) + || (psw->mask & psw_int_mask) != psw_int_mask + || ((flags & CPUSTAT_WAIT) && psw->addr != 0) + || (!(flags & CPUSTAT_WAIT) && (asn == p_asn || asn == s_asn))) { + return __sigp_emergency(vcpu, cpu_addr); + } else { + *reg &= 0xffffffff00000000UL; + *reg |= SIGP_STATUS_INCORRECT_STATE; + return SIGP_CC_STATUS_STORED; + } +} + static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr) { struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int; @@ -332,7 +363,8 @@ static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr, return rc; } -static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr) +/* Test whether the destination CPU is available and not busy */ +static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr) { struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int; struct kvm_s390_local_interrupt *li; @@ -351,9 +383,6 @@ static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr) spin_lock_bh(&li->lock); if (li->action_bits & ACTION_STOP_ON_STOP) rc = SIGP_CC_BUSY; - else - VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace", - cpu_addr); spin_unlock_bh(&li->lock); out: spin_unlock(&fi->lock); @@ -417,17 +446,31 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu) rc = __sigp_set_prefix(vcpu, cpu_addr, parameter, &vcpu->run->s.regs.gprs[r1]); break; + case SIGP_COND_EMERGENCY_SIGNAL: + rc = __sigp_conditional_emergency(vcpu, cpu_addr, parameter, + &vcpu->run->s.regs.gprs[r1]); + break; case SIGP_SENSE_RUNNING: vcpu->stat.instruction_sigp_sense_running++; rc = __sigp_sense_running(vcpu, cpu_addr, &vcpu->run->s.regs.gprs[r1]); break; + case SIGP_START: + rc = sigp_check_callable(vcpu, cpu_addr); + if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) + rc = -EOPNOTSUPP; /* Handle START in user space */ + break; case SIGP_RESTART: vcpu->stat.instruction_sigp_restart++; - rc = __sigp_restart(vcpu, cpu_addr); - if (rc == SIGP_CC_BUSY) - break; - /* user space must know about restart */ + rc = sigp_check_callable(vcpu, cpu_addr); + if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) { + VCPU_EVENT(vcpu, 4, + "sigp restart %x to handle userspace", + cpu_addr); + /* user space must know about restart */ + rc = -EOPNOTSUPP; + } + break; default: return -EOPNOTSUPP; } @@ -435,7 +478,6 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu) if (rc < 0) return rc; - vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44); - vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44; + kvm_s390_set_psw_cc(vcpu, rc); return 0; } |