projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 3c86c0d3 VP |
1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* | |
| 3 | * KVM L1 hypervisor optimizations on Hyper-V. | |
| 4 | */ | |
| 5 | ||
| 6 | #include <linux/kvm_host.h> | |
| 7 | #include <asm/mshyperv.h> | |
| 8 | ||
| 9 | #include "hyperv.h" | |
| 10 | #include "kvm_onhyperv.h" | |
| 11 | ||
| 12 | static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush, | |
| 13 | void *data) | |
| 14 | { | |
| 15 | struct kvm_tlb_range *range = data; | |
| 16 | ||
| 17 | return hyperv_fill_flush_guest_mapping_list(flush, range->start_gfn, | |
| 18 | range->pages); | |
| 19 | } | |
| 20 | ||
| 21 | static inline int hv_remote_flush_root_tdp(hpa_t root_tdp, | |
| 22 | struct kvm_tlb_range *range) | |
| 23 | { | |
| 24 | if (range) | |
| 25 | return hyperv_flush_guest_mapping_range(root_tdp, | |
| 26 | kvm_fill_hv_flush_list_func, (void *)range); | |
| 27 | else | |
| 28 | return hyperv_flush_guest_mapping(root_tdp); | |
| 29 | } | |
| 30 | ||
| 31 | int hv_remote_flush_tlb_with_range(struct kvm *kvm, | |
| 32 | struct kvm_tlb_range *range) | |
| 33 | { | |
| 34 | struct kvm_arch *kvm_arch = &kvm->arch; | |
| 35 | struct kvm_vcpu *vcpu; | |
| 46808a4c MZ |
36 | int ret = 0, nr_unique_valid_roots; |
| 37 | unsigned long i; | |
| 3c86c0d3 VP |
38 | hpa_t root; |
| 39 | ||
| 40 | spin_lock(&kvm_arch->hv_root_tdp_lock); | |
| 41 | ||
| 42 | if (!VALID_PAGE(kvm_arch->hv_root_tdp)) { | |
| 43 | nr_unique_valid_roots = 0; | |
| 44 | ||
| 45 | /* | |
| 46 | * Flush all valid roots, and see if all vCPUs have converged | |
| 47 | * on a common root, in which case future flushes can skip the | |
| 48 | * loop and flush the common root. | |
| 49 | */ | |
| 50 | kvm_for_each_vcpu(i, vcpu, kvm) { | |
| 51 | root = vcpu->arch.hv_root_tdp; | |
| 52 | if (!VALID_PAGE(root) || root == kvm_arch->hv_root_tdp) | |
| 53 | continue; | |
| 54 | ||
| 55 | /* | |
| 56 | * Set the tracked root to the first valid root. Keep | |
| 57 | * this root for the entirety of the loop even if more | |
| 58 | * roots are encountered as a low effort optimization | |
| 59 | * to avoid flushing the same (first) root again. | |
| 60 | */ | |
| 61 | if (++nr_unique_valid_roots == 1) | |
| 62 | kvm_arch->hv_root_tdp = root; | |
| 63 | ||
| 64 | if (!ret) | |
| 65 | ret = hv_remote_flush_root_tdp(root, range); | |
| 66 | ||
| 67 | /* | |
| 68 | * Stop processing roots if a failure occurred and | |
| 69 | * multiple valid roots have already been detected. | |
| 70 | */ | |
| 71 | if (ret && nr_unique_valid_roots > 1) | |
| 72 | break; | |
| 73 | } | |
| 74 | ||
| 75 | /* | |
| 76 | * The optimized flush of a single root can't be used if there | |
| 77 | * are multiple valid roots (obviously). | |
| 78 | */ | |
| 79 | if (nr_unique_valid_roots > 1) | |
| 80 | kvm_arch->hv_root_tdp = INVALID_PAGE; | |
| 81 | } else { | |
| 82 | ret = hv_remote_flush_root_tdp(kvm_arch->hv_root_tdp, range); | |
| 83 | } | |
| 84 | ||
| 85 | spin_unlock(&kvm_arch->hv_root_tdp_lock); | |
| 86 | return ret; | |
| 87 | } | |
| 88 | EXPORT_SYMBOL_GPL(hv_remote_flush_tlb_with_range); | |
| 89 | ||
| 90 | int hv_remote_flush_tlb(struct kvm *kvm) | |
| 91 | { | |
| 92 | return hv_remote_flush_tlb_with_range(kvm, NULL); | |
| 93 | } | |
| 94 | EXPORT_SYMBOL_GPL(hv_remote_flush_tlb); | |
| 3d4421f8 SC |
95 | |
| 96 | void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp) | |
| 97 | { | |
| 98 | struct kvm_arch *kvm_arch = &vcpu->kvm->arch; | |
| 99 | ||
| 100 | if (kvm_x86_ops.tlb_remote_flush == hv_remote_flush_tlb) { | |
| 101 | spin_lock(&kvm_arch->hv_root_tdp_lock); | |
| 102 | vcpu->arch.hv_root_tdp = root_tdp; | |
| 103 | if (root_tdp != kvm_arch->hv_root_tdp) | |
| 104 | kvm_arch->hv_root_tdp = INVALID_PAGE; | |
| 105 | spin_unlock(&kvm_arch->hv_root_tdp_lock); | |
| 106 | } | |
| 107 | } | |
| 108 | EXPORT_SYMBOL_GPL(hv_track_root_tdp); |