diff options
Diffstat (limited to 'arch/x86/kvm/svm/avic.c')
| -rw-r--r-- | arch/x86/kvm/svm/avic.c | 1027 |
1 files changed, 1027 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c new file mode 100644 index 000000000000..e80daa98682f --- /dev/null +++ b/arch/x86/kvm/svm/avic.c @@ -0,0 +1,1027 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Kernel-based Virtual Machine driver for Linux + * + * AMD SVM support + * + * Copyright (C) 2006 Qumranet, Inc. + * Copyright 2010 Red Hat, Inc. and/or its affiliates. + * + * Authors: + * Yaniv Kamay <yaniv@qumranet.com> + * Avi Kivity <avi@qumranet.com> + */ + +#define pr_fmt(fmt) "SVM: " fmt + +#include <linux/kvm_types.h> +#include <linux/hashtable.h> +#include <linux/amd-iommu.h> +#include <linux/kvm_host.h> + +#include <asm/irq_remapping.h> + +#include "trace.h" +#include "lapic.h" +#include "x86.h" +#include "irq.h" +#include "svm.h" + +/* enable / disable AVIC */ +int avic; +#ifdef CONFIG_X86_LOCAL_APIC +module_param(avic, int, S_IRUGO); +#endif + +#define SVM_AVIC_DOORBELL 0xc001011b + +#define AVIC_HPA_MASK ~((0xFFFULL << 52) | 0xFFF) + +/* + * 0xff is broadcast, so the max index allowed for physical APIC ID + * table is 0xfe. APIC IDs above 0xff are reserved. + */ +#define AVIC_MAX_PHYSICAL_ID_COUNT 255 + +#define AVIC_UNACCEL_ACCESS_WRITE_MASK 1 +#define AVIC_UNACCEL_ACCESS_OFFSET_MASK 0xFF0 +#define AVIC_UNACCEL_ACCESS_VECTOR_MASK 0xFFFFFFFF + +/* AVIC GATAG is encoded using VM and VCPU IDs */ +#define AVIC_VCPU_ID_BITS 8 +#define AVIC_VCPU_ID_MASK ((1 << AVIC_VCPU_ID_BITS) - 1) + +#define AVIC_VM_ID_BITS 24 +#define AVIC_VM_ID_NR (1 << AVIC_VM_ID_BITS) +#define AVIC_VM_ID_MASK ((1 << AVIC_VM_ID_BITS) - 1) + +#define AVIC_GATAG(x, y) (((x & AVIC_VM_ID_MASK) << AVIC_VCPU_ID_BITS) | \ + (y & AVIC_VCPU_ID_MASK)) +#define AVIC_GATAG_TO_VMID(x) ((x >> AVIC_VCPU_ID_BITS) & AVIC_VM_ID_MASK) +#define AVIC_GATAG_TO_VCPUID(x) (x & AVIC_VCPU_ID_MASK) + +/* Note: + * This hash table is used to map VM_ID to a struct kvm_svm, + * when handling AMD IOMMU GALOG notification to schedule in + * a particular vCPU. + */ +#define SVM_VM_DATA_HASH_BITS 8 +static DEFINE_HASHTABLE(svm_vm_data_hash, SVM_VM_DATA_HASH_BITS); +static u32 next_vm_id = 0; +static bool next_vm_id_wrapped = 0; +static DEFINE_SPINLOCK(svm_vm_data_hash_lock); + +/* + * This is a wrapper of struct amd_iommu_ir_data. + */ +struct amd_svm_iommu_ir { + struct list_head node; /* Used by SVM for per-vcpu ir_list */ + void *data; /* Storing pointer to struct amd_ir_data */ +}; + +enum avic_ipi_failure_cause { + AVIC_IPI_FAILURE_INVALID_INT_TYPE, + AVIC_IPI_FAILURE_TARGET_NOT_RUNNING, + AVIC_IPI_FAILURE_INVALID_TARGET, + AVIC_IPI_FAILURE_INVALID_BACKING_PAGE, +}; + +/* Note: + * This function is called from IOMMU driver to notify + * SVM to schedule in a particular vCPU of a particular VM. + */ +int avic_ga_log_notifier(u32 ga_tag) +{ + unsigned long flags; + struct kvm_svm *kvm_svm; + struct kvm_vcpu *vcpu = NULL; + u32 vm_id = AVIC_GATAG_TO_VMID(ga_tag); + u32 vcpu_id = AVIC_GATAG_TO_VCPUID(ga_tag); + + pr_debug("SVM: %s: vm_id=%#x, vcpu_id=%#x\n", __func__, vm_id, vcpu_id); + trace_kvm_avic_ga_log(vm_id, vcpu_id); + + spin_lock_irqsave(&svm_vm_data_hash_lock, flags); + hash_for_each_possible(svm_vm_data_hash, kvm_svm, hnode, vm_id) { + if (kvm_svm->avic_vm_id != vm_id) + continue; + vcpu = kvm_get_vcpu_by_id(&kvm_svm->kvm, vcpu_id); + break; + } + spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); + + /* Note: + * At this point, the IOMMU should have already set the pending + * bit in the vAPIC backing page. So, we just need to schedule + * in the vcpu. + */ + if (vcpu) + kvm_vcpu_wake_up(vcpu); + + return 0; +} + +void avic_vm_destroy(struct kvm *kvm) +{ + unsigned long flags; + struct kvm_svm *kvm_svm = to_kvm_svm(kvm); + + if (!avic) + return; + + if (kvm_svm->avic_logical_id_table_page) + __free_page(kvm_svm->avic_logical_id_table_page); + if (kvm_svm->avic_physical_id_table_page) + __free_page(kvm_svm->avic_physical_id_table_page); + + spin_lock_irqsave(&svm_vm_data_hash_lock, flags); + hash_del(&kvm_svm->hnode); + spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); +} + +int avic_vm_init(struct kvm *kvm) +{ + unsigned long flags; + int err = -ENOMEM; + struct kvm_svm *kvm_svm = to_kvm_svm(kvm); + struct kvm_svm *k2; + struct page *p_page; + struct page *l_page; + u32 vm_id; + + if (!avic) + return 0; + + /* Allocating physical APIC ID table (4KB) */ + p_page = alloc_page(GFP_KERNEL_ACCOUNT); + if (!p_page) + goto free_avic; + + kvm_svm->avic_physical_id_table_page = p_page; + clear_page(page_address(p_page)); + + /* Allocating logical APIC ID table (4KB) */ + l_page = alloc_page(GFP_KERNEL_ACCOUNT); + if (!l_page) + goto free_avic; + + kvm_svm->avic_logical_id_table_page = l_page; + clear_page(page_address(l_page)); + + spin_lock_irqsave(&svm_vm_data_hash_lock, flags); + again: + vm_id = next_vm_id = (next_vm_id + 1) & AVIC_VM_ID_MASK; + if (vm_id == 0) { /* id is 1-based, zero is not okay */ + next_vm_id_wrapped = 1; + goto again; + } + /* Is it still in use? Only possible if wrapped at least once */ + if (next_vm_id_wrapped) { + hash_for_each_possible(svm_vm_data_hash, k2, hnode, vm_id) { + if (k2->avic_vm_id == vm_id) + goto again; + } + } + kvm_svm->avic_vm_id = vm_id; + hash_add(svm_vm_data_hash, &kvm_svm->hnode, kvm_svm->avic_vm_id); + spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags); + + return 0; + +free_avic: + avic_vm_destroy(kvm); + return err; +} + +void avic_init_vmcb(struct vcpu_svm *svm) +{ + struct vmcb *vmcb = svm->vmcb; + struct kvm_svm *kvm_svm = to_kvm_svm(svm->vcpu.kvm); + phys_addr_t bpa = __sme_set(page_to_phys(svm->avic_backing_page)); + phys_addr_t lpa = __sme_set(page_to_phys(kvm_svm->avic_logical_id_table_page)); + phys_addr_t ppa = __sme_set(page_to_phys(kvm_svm->avic_physical_id_table_page)); + + vmcb->control.avic_backing_page = bpa & AVIC_HPA_MASK; + vmcb->control.avic_logical_id = lpa & AVIC_HPA_MASK; + vmcb->control.avic_physical_id = ppa & AVIC_HPA_MASK; + vmcb->control.avic_physical_id |= AVIC_MAX_PHYSICAL_ID_COUNT; + if (kvm_apicv_activated(svm->vcpu.kvm)) + vmcb->control.int_ctl |= AVIC_ENABLE_MASK; + else + vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK; +} + +static u64 *avic_get_physical_id_entry(struct kvm_vcpu *vcpu, + unsigned int index) +{ + u64 *avic_physical_id_table; + struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm); + + if (index >= AVIC_MAX_PHYSICAL_ID_COUNT) + return NULL; + + avic_physical_id_table = page_address(kvm_svm->avic_physical_id_table_page); + + return &avic_physical_id_table[index]; +} + +/** + * Note: + * AVIC hardware walks the nested page table to check permissions, + * but does not use the SPA address specified in the leaf page + * table entry since it uses address in the AVIC_BACKING_PAGE pointer + * field of the VMCB. Therefore, we set up the + * APIC_ACCESS_PAGE_PRIVATE_MEMSLOT (4KB) here. + */ +static int avic_update_access_page(struct kvm *kvm, bool activate) +{ + int ret = 0; + + mutex_lock(&kvm->slots_lock); + /* + * During kvm_destroy_vm(), kvm_pit_set_reinject() could trigger + * APICv mode change, which update APIC_ACCESS_PAGE_PRIVATE_MEMSLOT + * memory region. So, we need to ensure that kvm->mm == current->mm. + */ + if ((kvm->arch.apic_access_page_done == activate) || + (kvm->mm != current->mm)) + goto out; + + ret = __x86_set_memory_region(kvm, + APIC_ACCESS_PAGE_PRIVATE_MEMSLOT, + APIC_DEFAULT_PHYS_BASE, + activate ? PAGE_SIZE : 0); + if (ret) + goto out; + + kvm->arch.apic_access_page_done = activate; +out: + mutex_unlock(&kvm->slots_lock); + return ret; +} + +static int avic_init_backing_page(struct kvm_vcpu *vcpu) +{ + u64 *entry, new_entry; + int id = vcpu->vcpu_id; + struct vcpu_svm *svm = to_svm(vcpu); + + if (id >= AVIC_MAX_PHYSICAL_ID_COUNT) + return -EINVAL; + + if (!svm->vcpu.arch.apic->regs) + return -EINVAL; + + if (kvm_apicv_activated(vcpu->kvm)) { + int ret; + + ret = avic_update_access_page(vcpu->kvm, true); + if (ret) + return ret; + } + + svm->avic_backing_page = virt_to_page(svm->vcpu.arch.apic->regs); + + /* Setting AVIC backing page address in the phy APIC ID table */ + entry = avic_get_physical_id_entry(vcpu, id); + if (!entry) + return -EINVAL; + + new_entry = __sme_set((page_to_phys(svm->avic_backing_page) & + AVIC_PHYSICAL_ID_ENTRY_BACKING_PAGE_MASK) | + AVIC_PHYSICAL_ID_ENTRY_VALID_MASK); + WRITE_ONCE(*entry, new_entry); + + svm->avic_physical_id_cache = entry; + + return 0; +} + +int avic_incomplete_ipi_interception(struct vcpu_svm *svm) +{ + u32 icrh = svm->vmcb->control.exit_info_1 >> 32; + u32 icrl = svm->vmcb->control.exit_info_1; + u32 id = svm->vmcb->control.exit_info_2 >> 32; + u32 index = svm->vmcb->control.exit_info_2 & 0xFF; + struct kvm_lapic *apic = svm->vcpu.arch.apic; + + trace_kvm_avic_incomplete_ipi(svm->vcpu.vcpu_id, icrh, icrl, id, index); + + switch (id) { + case AVIC_IPI_FAILURE_INVALID_INT_TYPE: + /* + * AVIC hardware handles the generation of + * IPIs when the specified Message Type is Fixed + * (also known as fixed delivery mode) and + * the Trigger Mode is edge-triggered. The hardware + * also supports self and broadcast delivery modes + * specified via the Destination Shorthand(DSH) + * field of the ICRL. Logical and physical APIC ID + * formats are supported. All other IPI types cause + * a #VMEXIT, which needs to emulated. + */ + kvm_lapic_reg_write(apic, APIC_ICR2, icrh); + kvm_lapic_reg_write(apic, APIC_ICR, icrl); + break; + case AVIC_IPI_FAILURE_TARGET_NOT_RUNNING: { + int i; + struct kvm_vcpu *vcpu; + struct kvm *kvm = svm->vcpu.kvm; + struct kvm_lapic *apic = svm->vcpu.arch.apic; + + /* + * At this point, we expect that the AVIC HW has already + * set the appropriate IRR bits on the valid target + * vcpus. So, we just need to kick the appropriate vcpu. + */ + kvm_for_each_vcpu(i, vcpu, kvm) { + bool m = kvm_apic_match_dest(vcpu, apic, + icrl & APIC_SHORT_MASK, + GET_APIC_DEST_FIELD(icrh), + icrl & APIC_DEST_MASK); + + if (m && !avic_vcpu_is_running(vcpu)) + kvm_vcpu_wake_up(vcpu); + } + break; + } + case AVIC_IPI_FAILURE_INVALID_TARGET: + WARN_ONCE(1, "Invalid IPI target: index=%u, vcpu=%d, icr=%#0x:%#0x\n", + index, svm->vcpu.vcpu_id, icrh, icrl); + break; + case AVIC_IPI_FAILURE_INVALID_BACKING_PAGE: + WARN_ONCE(1, "Invalid backing page\n"); + break; + default: + pr_err("Unknown IPI interception\n"); + } + + return 1; +} + +static u32 *avic_get_logical_id_entry(struct kvm_vcpu *vcpu, u32 ldr, bool flat) +{ + struct kvm_svm *kvm_svm = to_kvm_svm(vcpu->kvm); + int index; + u32 *logical_apic_id_table; + int dlid = GET_APIC_LOGICAL_ID(ldr); + + if (!dlid) + return NULL; + + if (flat) { /* flat */ + index = ffs(dlid) - 1; + if (index > 7) + return NULL; + } else { /* cluster */ + int cluster = (dlid & 0xf0) >> 4; + int apic = ffs(dlid & 0x0f) - 1; + + if ((apic < 0) || (apic > 7) || + (cluster >= 0xf)) + return NULL; + index = (cluster << 2) + apic; + } + + logical_apic_id_table = (u32 *) page_address(kvm_svm->avic_logical_id_table_page); + + return &logical_apic_id_table[index]; +} + +static int avic_ldr_write(struct kvm_vcpu *vcpu, u8 g_physical_id, u32 ldr) +{ + bool flat; + u32 *entry, new_entry; + + flat = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR) == APIC_DFR_FLAT; + entry = avic_get_logical_id_entry(vcpu, ldr, flat); + if (!entry) + return -EINVAL; + + new_entry = READ_ONCE(*entry); + new_entry &= ~AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK; + new_entry |= (g_physical_id & AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK); + new_entry |= AVIC_LOGICAL_ID_ENTRY_VALID_MASK; + WRITE_ONCE(*entry, new_entry); + + return 0; +} + +static void avic_invalidate_logical_id_entry(struct kvm_vcpu *vcpu) +{ + struct vcpu_svm *svm = to_svm(vcpu); + bool flat = svm->dfr_reg == APIC_DFR_FLAT; + u32 *entry = avic_get_logical_id_entry(vcpu, svm->ldr_reg, flat); + + if (entry) + clear_bit(AVIC_LOGICAL_ID_ENTRY_VALID_BIT, (unsigned long *)entry); +} + +static int avic_handle_ldr_update(struct kvm_vcpu *vcpu) +{ + int ret = 0; + struct vcpu_svm *svm = to_svm(vcpu); + u32 ldr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_LDR); + u32 id = kvm_xapic_id(vcpu->arch.apic); + + if (ldr == svm->ldr_reg) + return 0; + + avic_invalidate_logical_id_entry(vcpu); + + if (ldr) + ret = avic_ldr_write(vcpu, id, ldr); + + if (!ret) + svm->ldr_reg = ldr; + + return ret; +} + +static int avic_handle_apic_id_update(struct kvm_vcpu *vcpu) +{ + u64 *old, *new; + struct vcpu_svm *svm = to_svm(vcpu); + u32 id = kvm_xapic_id(vcpu->arch.apic); + + if (vcpu->vcpu_id == id) + return 0; + + old = avic_get_physical_id_entry(vcpu, vcpu->vcpu_id); + new = avic_get_physical_id_entry(vcpu, id); + if (!new || !old) + return 1; + + /* We need to move physical_id_entry to new offset */ + *new = *old; + *old = 0ULL; + to_svm(vcpu)->avic_physical_id_cache = new; + + /* + * Also update the guest physical APIC ID in the logical + * APIC ID table entry if already setup the LDR. + */ + if (svm->ldr_reg) + avic_handle_ldr_update(vcpu); + + return 0; +} + +static void avic_handle_dfr_update(struct kvm_vcpu *vcpu) +{ + struct vcpu_svm *svm = to_svm(vcpu); + u32 dfr = kvm_lapic_get_reg(vcpu->arch.apic, APIC_DFR); + + if (svm->dfr_reg == dfr) + return; + + avic_invalidate_logical_id_entry(vcpu); + svm->dfr_reg = dfr; +} + +static int avic_unaccel_trap_write(struct vcpu_svm *svm) +{ + struct kvm_lapic *apic = svm->vcpu.arch.apic; + u32 offset = svm->vmcb->control.exit_info_1 & + AVIC_UNACCEL_ACCESS_OFFSET_MASK; + + switch (offset) { + case APIC_ID: + if (avic_handle_apic_id_update(&svm->vcpu)) + return 0; + break; + case APIC_LDR: + if (avic_handle_ldr_update(&svm->vcpu)) + return 0; + break; + case APIC_DFR: + avic_handle_dfr_update(&svm->vcpu); + break; + default: + break; + } + + kvm_lapic_reg_write(apic, offset, kvm_lapic_get_reg(apic, offset)); + + return 1; +} + +static bool is_avic_unaccelerated_access_trap(u32 offset) +{ + bool ret = false; + + switch (offset) { + case APIC_ID: + case APIC_EOI: + case APIC_RRR: + case APIC_LDR: + case APIC_DFR: + case APIC_SPIV: + case APIC_ESR: + case APIC_ICR: + case APIC_LVTT: + case APIC_LVTTHMR: + case APIC_LVTPC: + case APIC_LVT0: + case APIC_LVT1: + case APIC_LVTERR: + case APIC_TMICT: + case APIC_TDCR: + ret = true; + break; + default: + break; + } + return ret; +} + +int avic_unaccelerated_access_interception(struct vcpu_svm *svm) +{ + int ret = 0; + u32 offset = svm->vmcb->control.exit_info_1 & + AVIC_UNACCEL_ACCESS_OFFSET_MASK; + u32 vector = svm->vmcb->control.exit_info_2 & + AVIC_UNACCEL_ACCESS_VECTOR_MASK; + bool write = (svm->vmcb->control.exit_info_1 >> 32) & + AVIC_UNACCEL_ACCESS_WRITE_MASK; + bool trap = is_avic_unaccelerated_access_trap(offset); + + trace_kvm_avic_unaccelerated_access(svm->vcpu.vcpu_id, offset, + trap, write, vector); + if (trap) { + /* Handling Trap */ + WARN_ONCE(!write, "svm: Handling trap read.\n"); + ret = avic_unaccel_trap_write(svm); + } else { + /* Handling Fault */ + ret = kvm_emulate_instruction(&svm->vcpu, 0); + } + + return ret; +} + +int avic_init_vcpu(struct vcpu_svm *svm) +{ + int ret; + struct kvm_vcpu *vcpu = &svm->vcpu; + + if (!avic || !irqchip_in_kernel(vcpu->kvm)) + return 0; + + ret = avic_init_backing_page(&svm->vcpu); + if (ret) + return ret; + + INIT_LIST_HEAD(&svm->ir_list); + spin_lock_init(&svm->ir_list_lock); + svm->dfr_reg = APIC_DFR_FLAT; + + return ret; +} + +void avic_post_state_restore(struct kvm_vcpu *vcpu) +{ + if (avic_handle_apic_id_update(vcpu) != 0) + return; + avic_handle_dfr_update(vcpu); + avic_handle_ldr_update(vcpu); +} + +void svm_toggle_avic_for_irq_window(struct kvm_vcpu *vcpu, bool activate) +{ + if (!avic || !lapic_in_kernel(vcpu)) + return; + + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + kvm_request_apicv_update(vcpu->kvm, activate, + APICV_INHIBIT_REASON_IRQWIN); + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); +} + +void svm_set_virtual_apic_mode(struct kvm_vcpu *vcpu) +{ + return; +} + +void svm_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr) +{ +} + +void svm_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr) +{ +} + +static int svm_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate) +{ + int ret = 0; + unsigned long flags; + struct amd_svm_iommu_ir *ir; + struct vcpu_svm *svm = to_svm(vcpu); + + if (!kvm_arch_has_assigned_device(vcpu->kvm)) + return 0; + + /* + * Here, we go through the per-vcpu ir_list to update all existing + * interrupt remapping table entry targeting this vcpu. + */ + spin_lock_irqsave(&svm->ir_list_lock, flags); + + if (list_empty(&svm->ir_list)) + goto out; + + list_for_each_entry(ir, &svm->ir_list, node) { + if (activate) + ret = amd_iommu_activate_guest_mode(ir->data); + else + ret = amd_iommu_deactivate_guest_mode(ir->data); + if (ret) + break; + } +out: + spin_unlock_irqrestore(&svm->ir_list_lock, flags); + return ret; +} + +void svm_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu) +{ + struct vcpu_svm *svm = to_svm(vcpu); + struct vmcb *vmcb = svm->vmcb; + bool activated = kvm_vcpu_apicv_active(vcpu); + + if (!avic) + return; + + if (activated) { + /** + * During AVIC temporary deactivation, guest could update + * APIC ID, DFR and LDR registers, which would not be trapped + * by avic_unaccelerated_access_interception(). In this case, + * we need to check and update the AVIC logical APIC ID table + * accordingly before re-activating. + */ + avic_post_state_restore(vcpu); + vmcb->control.int_ctl |= AVIC_ENABLE_MASK; + } else { + vmcb->control.int_ctl &= ~AVIC_ENABLE_MASK; + } + mark_dirty(vmcb, VMCB_AVIC); + + svm_set_pi_irte_mode(vcpu, activated); +} + +void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap) +{ + return; +} + +int svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec) +{ + if (!vcpu->arch.apicv_active) + return -1; + + kvm_lapic_set_irr(vec, vcpu->arch.apic); + smp_mb__after_atomic(); + + if (avic_vcpu_is_running(vcpu)) { + int cpuid = vcpu->cpu; + + if (cpuid != get_cpu()) + wrmsrl(SVM_AVIC_DOORBELL, kvm_cpu_get_apicid(cpuid)); + put_cpu(); + } else + kvm_vcpu_wake_up(vcpu); + + return 0; +} + +bool svm_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu) +{ + return false; +} + +static void svm_ir_list_del(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi) +{ + unsigned long flags; + struct amd_svm_iommu_ir *cur; + + spin_lock_irqsave(&svm->ir_list_lock, flags); + list_for_each_entry(cur, &svm->ir_list, node) { + if (cur->data != pi->ir_data) + continue; + list_del(&cur->node); + kfree(cur); + break; + } + spin_unlock_irqrestore(&svm->ir_list_lock, flags); +} + +static int svm_ir_list_add(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi) +{ + int ret = 0; + unsigned long flags; + struct amd_svm_iommu_ir *ir; + + /** + * In some cases, the existing irte is updaed and re-set, + * so we need to check here if it's already been * added + * to the ir_list. + */ + if (pi->ir_data && (pi->prev_ga_tag != 0)) { + struct kvm *kvm = svm->vcpu.kvm; + u32 vcpu_id = AVIC_GATAG_TO_VCPUID(pi->prev_ga_tag); + struct kvm_vcpu *prev_vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id); + struct vcpu_svm *prev_svm; + + if (!prev_vcpu) { + ret = -EINVAL; + goto out; + } + + prev_svm = to_svm(prev_vcpu); + svm_ir_list_del(prev_svm, pi); + } + + /** + * Allocating new amd_iommu_pi_data, which will get + * add to the per-vcpu ir_list. + */ + ir = kzalloc(sizeof(struct amd_svm_iommu_ir), GFP_KERNEL_ACCOUNT); + if (!ir) { + ret = -ENOMEM; + goto out; + } + ir->data = pi->ir_data; + + spin_lock_irqsave(&svm->ir_list_lock, flags); + list_add(&ir->node, &svm->ir_list); + spin_unlock_irqrestore(&svm->ir_list_lock, flags); +out: + return ret; +} + +/** + * Note: + * The HW cannot support posting multicast/broadcast + * interrupts to a vCPU. So, we still use legacy interrupt + * remapping for these kind of interrupts. + * + * For lowest-priority interrupts, we only support + * those with single CPU as the destination, e.g. user + * configures the interrupts via /proc/irq or uses + * irqbalance to make the interrupts single-CPU. + */ +static int +get_pi_vcpu_info(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e, + struct vcpu_data *vcpu_info, struct vcpu_svm **svm) +{ + struct kvm_lapic_irq irq; + struct kvm_vcpu *vcpu = NULL; + + kvm_set_msi_irq(kvm, e, &irq); + + if (!kvm_intr_is_single_vcpu(kvm, &irq, &vcpu) || + !kvm_irq_is_postable(&irq)) { + pr_debug("SVM: %s: use legacy intr remap mode for irq %u\n", + __func__, irq.vector); + return -1; + } + + pr_debug("SVM: %s: use GA mode for irq %u\n", __func__, + irq.vector); + *svm = to_svm(vcpu); + vcpu_info->pi_desc_addr = __sme_set(page_to_phys((*svm)->avic_backing_page)); + vcpu_info->vector = irq.vector; + + return 0; +} + +/* + * svm_update_pi_irte - set IRTE for Posted-Interrupts + * + * @kvm: kvm + * @host_irq: host irq of the interrupt + * @guest_irq: gsi of the interrupt + * @set: set or unset PI + * returns 0 on success, < 0 on failure + */ +int svm_update_pi_irte(struct kvm *kvm, unsigned int host_irq, + uint32_t guest_irq, bool set) +{ + struct kvm_kernel_irq_routing_entry *e; + struct kvm_irq_routing_table *irq_rt; + int idx, ret = -EINVAL; + + if (!kvm_arch_has_assigned_device(kvm) || + !irq_remapping_cap(IRQ_POSTING_CAP)) + return 0; + + pr_debug("SVM: %s: host_irq=%#x, guest_irq=%#x, set=%#x\n", + __func__, host_irq, guest_irq, set); + + idx = srcu_read_lock(&kvm->irq_srcu); + irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu); + WARN_ON(guest_irq >= irq_rt->nr_rt_entries); + + hlist_for_each_entry(e, &irq_rt->map[guest_irq], link) { + struct vcpu_data vcpu_info; + struct vcpu_svm *svm = NULL; + + if (e->type != KVM_IRQ_ROUTING_MSI) + continue; + + /** + * Here, we setup with legacy mode in the following cases: + * 1. When cannot target interrupt to a specific vcpu. + * 2. Unsetting posted interrupt. + * 3. APIC virtialization is disabled for the vcpu. + * 4. IRQ has incompatible delivery mode (SMI, INIT, etc) + */ + if (!get_pi_vcpu_info(kvm, e, &vcpu_info, &svm) && set && + kvm_vcpu_apicv_active(&svm->vcpu)) { + struct amd_iommu_pi_data pi; + + /* Try to enable guest_mode in IRTE */ + pi.base = __sme_set(page_to_phys(svm->avic_backing_page) & + AVIC_HPA_MASK); + pi.ga_tag = AVIC_GATAG(to_kvm_svm(kvm)->avic_vm_id, + svm->vcpu.vcpu_id); + pi.is_guest_mode = true; + pi.vcpu_data = &vcpu_info; + ret = irq_set_vcpu_affinity(host_irq, &pi); + + /** + * Here, we successfully setting up vcpu affinity in + * IOMMU guest mode. Now, we need to store the posted + * interrupt information in a per-vcpu ir_list so that + * we can reference to them directly when we update vcpu + * scheduling information in IOMMU irte. + */ + if (!ret && pi.is_guest_mode) + svm_ir_list_add(svm, &pi); + } else { + /* Use legacy mode in IRTE */ + struct amd_iommu_pi_data pi; + + /** + * Here, pi is used to: + * - Tell IOMMU to use legacy mode for this interrupt. + * - Retrieve ga_tag of prior interrupt remapping data. + */ + pi.is_guest_mode = false; + ret = irq_set_vcpu_affinity(host_irq, &pi); + + /** + * Check if the posted interrupt was previously + * setup with the guest_mode by checking if the ga_tag + * was cached. If so, we need to clean up the per-vcpu + * ir_list. + */ + if (!ret && pi.prev_ga_tag) { + int id = AVIC_GATAG_TO_VCPUID(pi.prev_ga_tag); + struct kvm_vcpu *vcpu; + + vcpu = kvm_get_vcpu_by_id(kvm, id); + if (vcpu) + svm_ir_list_del(to_svm(vcpu), &pi); + } + } + + if (!ret && svm) { + trace_kvm_pi_irte_update(host_irq, svm->vcpu.vcpu_id, + e->gsi, vcpu_info.vector, + vcpu_info.pi_desc_addr, set); + } + + if (ret < 0) { + pr_err("%s: failed to update PI IRTE\n", __func__); + goto out; + } + } + + ret = 0; +out: + srcu_read_unlock(&kvm->irq_srcu, idx); + return ret; +} + +bool svm_check_apicv_inhibit_reasons(ulong bit) +{ + ulong supported = BIT(APICV_INHIBIT_REASON_DISABLE) | + BIT(APICV_INHIBIT_REASON_HYPERV) | + BIT(APICV_INHIBIT_REASON_NESTED) | + BIT(APICV_INHIBIT_REASON_IRQWIN) | + BIT(APICV_INHIBIT_REASON_PIT_REINJ) | + BIT(APICV_INHIBIT_REASON_X2APIC); + + return supported & BIT(bit); +} + +void svm_pre_update_apicv_exec_ctrl(struct kvm *kvm, bool activate) +{ + avic_update_access_page(kvm, activate); +} + +static inline int +avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu, bool r) +{ + int ret = 0; + unsigned long flags; + struct amd_svm_iommu_ir *ir; + struct vcpu_svm *svm = to_svm(vcpu); + + if (!kvm_arch_has_assigned_device(vcpu->kvm)) + return 0; + + /* + * Here, we go through the per-vcpu ir_list to update all existing + * interrupt remapping table entry targeting this vcpu. + */ + spin_lock_irqsave(&svm->ir_list_lock, flags); + + if (list_empty(&svm->ir_list)) + goto out; + + list_for_each_entry(ir, &svm->ir_list, node) { + ret = amd_iommu_update_ga(cpu, r, ir->data); + if (ret) + break; + } +out: + spin_unlock_irqrestore(&svm->ir_list_lock, flags); + return ret; +} + +void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + u64 entry; + /* ID = 0xff (broadcast), ID > 0xff (reserved) */ + int h_physical_id = kvm_cpu_get_apicid(cpu); + struct vcpu_svm *svm = to_svm(vcpu); + + if (!kvm_vcpu_apicv_active(vcpu)) + return; + + /* + * Since the host physical APIC id is 8 bits, + * we can support host APIC ID upto 255. + */ + if (WARN_ON(h_physical_id > AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK)) + return; + + entry = READ_ONCE(*(svm->avic_physical_id_cache)); + WARN_ON(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK); + + entry &= ~AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK; + entry |= (h_physical_id & AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK); + + entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; + if (svm->avic_is_running) + entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; + + WRITE_ONCE(*(svm->avic_physical_id_cache), entry); + avic_update_iommu_vcpu_affinity(vcpu, h_physical_id, + svm->avic_is_running); +} + +void avic_vcpu_put(struct kvm_vcpu *vcpu) +{ + u64 entry; + struct vcpu_svm *svm = to_svm(vcpu); + + if (!kvm_vcpu_apicv_active(vcpu)) + return; + + entry = READ_ONCE(*(svm->avic_physical_id_cache)); + if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK) + avic_update_iommu_vcpu_affinity(vcpu, -1, 0); + + entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK; + WRITE_ONCE(*(svm->avic_physical_id_cache), entry); +} + +/** + * This function is called during VCPU halt/unhalt. + */ +static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run) +{ + struct vcpu_svm *svm = to_svm(vcpu); + + svm->avic_is_running = is_run; + if (is_run) + avic_vcpu_load(vcpu, vcpu->cpu); + else + avic_vcpu_put(vcpu); +} + +void svm_vcpu_blocking(struct kvm_vcpu *vcpu) +{ + avic_set_running(vcpu, false); +} + +void svm_vcpu_unblocking(struct kvm_vcpu *vcpu) +{ + if (kvm_check_request(KVM_REQ_APICV_UPDATE, vcpu)) + kvm_vcpu_update_apicv(vcpu); + avic_set_running(vcpu, true); +} |