diff options
| -rw-r--r-- | arch/powerpc/kvm/book3s_xive.c | 65 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_xive.h | 4 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_xive_native.c | 18 |
3 files changed, 62 insertions, 25 deletions
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c index d84da9f6ee88..6c35b3d95986 100644 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -1213,13 +1213,13 @@ void kvmppc_xive_cleanup_vcpu(struct kvm_vcpu *vcpu) static bool kvmppc_xive_vcpu_id_valid(struct kvmppc_xive *xive, u32 cpu) { - /* We have a block of KVM_MAX_VCPUS VPs. We just need to check + /* We have a block of xive->nr_servers VPs. We just need to check * raw vCPU ids are below the expected limit for this guest's * core stride ; kvmppc_pack_vcpu_id() will pack them down to an * index that can be safely used to compute a VP id that belongs * to the VP block. */ - return cpu < KVM_MAX_VCPUS * xive->kvm->arch.emul_smt_mode; + return cpu < xive->nr_servers * xive->kvm->arch.emul_smt_mode; } int kvmppc_xive_compute_vp_id(struct kvmppc_xive *xive, u32 cpu, u32 *vp) @@ -1231,6 +1231,14 @@ int kvmppc_xive_compute_vp_id(struct kvmppc_xive *xive, u32 cpu, u32 *vp) return -EINVAL; } + if (xive->vp_base == XIVE_INVALID_VP) { + xive->vp_base = xive_native_alloc_vp_block(xive->nr_servers); + pr_devel("VP_Base=%x nr_servers=%d\n", xive->vp_base, xive->nr_servers); + + if (xive->vp_base == XIVE_INVALID_VP) + return -ENOSPC; + } + vp_id = kvmppc_xive_vp(xive, cpu); if (kvmppc_xive_vp_in_use(xive->kvm, vp_id)) { pr_devel("Duplicate !\n"); @@ -1858,6 +1866,43 @@ int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, return 0; } +int kvmppc_xive_set_nr_servers(struct kvmppc_xive *xive, u64 addr) +{ + u32 __user *ubufp = (u32 __user *) addr; + u32 nr_servers; + int rc = 0; + + if (get_user(nr_servers, ubufp)) + return -EFAULT; + + pr_devel("%s nr_servers=%u\n", __func__, nr_servers); + + if (!nr_servers || nr_servers > KVM_MAX_VCPU_ID) + return -EINVAL; + + mutex_lock(&xive->lock); + if (xive->vp_base != XIVE_INVALID_VP) + /* The VP block is allocated once and freed when the device + * is released. Better not allow to change its size since its + * used by connect_vcpu to validate vCPU ids are valid (eg, + * setting it back to a higher value could allow connect_vcpu + * to come up with a VP id that goes beyond the VP block, which + * is likely to cause a crash in OPAL). + */ + rc = -EBUSY; + else if (nr_servers > KVM_MAX_VCPUS) + /* We don't need more servers. Higher vCPU ids get packed + * down below KVM_MAX_VCPUS by kvmppc_pack_vcpu_id(). + */ + xive->nr_servers = KVM_MAX_VCPUS; + else + xive->nr_servers = nr_servers; + + mutex_unlock(&xive->lock); + + return rc; +} + static int xive_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) { struct kvmppc_xive *xive = dev->private; @@ -2025,7 +2070,6 @@ static int kvmppc_xive_create(struct kvm_device *dev, u32 type) { struct kvmppc_xive *xive; struct kvm *kvm = dev->kvm; - int ret = 0; pr_devel("Creating xive for partition\n"); @@ -2049,18 +2093,15 @@ static int kvmppc_xive_create(struct kvm_device *dev, u32 type) else xive->q_page_order = xive->q_order - PAGE_SHIFT; - /* Allocate a bunch of VPs */ - xive->vp_base = xive_native_alloc_vp_block(KVM_MAX_VCPUS); - pr_devel("VP_Base=%x\n", xive->vp_base); - - if (xive->vp_base == XIVE_INVALID_VP) - ret = -ENOMEM; + /* VP allocation is delayed to the first call to connect_vcpu */ + xive->vp_base = XIVE_INVALID_VP; + /* KVM_MAX_VCPUS limits the number of VMs to roughly 64 per sockets + * on a POWER9 system. + */ + xive->nr_servers = KVM_MAX_VCPUS; xive->single_escalation = xive_native_has_single_escalation(); - if (ret) - return ret; - kvm->arch.xive = xive; return 0; } diff --git a/arch/powerpc/kvm/book3s_xive.h b/arch/powerpc/kvm/book3s_xive.h index 90cf6ec35a68..382e3a56e789 100644 --- a/arch/powerpc/kvm/book3s_xive.h +++ b/arch/powerpc/kvm/book3s_xive.h @@ -135,6 +135,9 @@ struct kvmppc_xive { /* Flags */ u8 single_escalation; + /* Number of entries in the VP block */ + u32 nr_servers; + struct kvmppc_xive_ops *ops; struct address_space *mapping; struct mutex mapping_lock; @@ -297,6 +300,7 @@ struct kvmppc_xive *kvmppc_xive_get_device(struct kvm *kvm, u32 type); void xive_cleanup_single_escalation(struct kvm_vcpu *vcpu, struct kvmppc_xive_vcpu *xc, int irq); int kvmppc_xive_compute_vp_id(struct kvmppc_xive *xive, u32 cpu, u32 *vp); +int kvmppc_xive_set_nr_servers(struct kvmppc_xive *xive, u64 addr); #endif /* CONFIG_KVM_XICS */ #endif /* _KVM_PPC_BOOK3S_XICS_H */ diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c index 5bb480b2aafd..8ab333eabeef 100644 --- a/arch/powerpc/kvm/book3s_xive_native.c +++ b/arch/powerpc/kvm/book3s_xive_native.c @@ -1060,7 +1060,6 @@ static int kvmppc_xive_native_create(struct kvm_device *dev, u32 type) { struct kvmppc_xive *xive; struct kvm *kvm = dev->kvm; - int ret = 0; pr_devel("Creating xive native device\n"); @@ -1077,23 +1076,16 @@ static int kvmppc_xive_native_create(struct kvm_device *dev, u32 type) mutex_init(&xive->mapping_lock); mutex_init(&xive->lock); - /* - * Allocate a bunch of VPs. KVM_MAX_VCPUS is a large value for - * a default. Getting the max number of CPUs the VM was - * configured with would improve our usage of the XIVE VP space. + /* VP allocation is delayed to the first call to connect_vcpu */ + xive->vp_base = XIVE_INVALID_VP; + /* KVM_MAX_VCPUS limits the number of VMs to roughly 64 per sockets + * on a POWER9 system. */ - xive->vp_base = xive_native_alloc_vp_block(KVM_MAX_VCPUS); - pr_devel("VP_Base=%x\n", xive->vp_base); - - if (xive->vp_base == XIVE_INVALID_VP) - ret = -ENXIO; + xive->nr_servers = KVM_MAX_VCPUS; xive->single_escalation = xive_native_has_single_escalation(); xive->ops = &kvmppc_xive_native_ops; - if (ret) - return ret; - kvm->arch.xive = xive; return 0; } |