diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/kvm/kvm_onhyperv.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kvm/kvm_onhyperv.c')
-rw-r--r-- | arch/x86/kvm/kvm_onhyperv.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/arch/x86/kvm/kvm_onhyperv.c b/arch/x86/kvm/kvm_onhyperv.c new file mode 100644 index 000000000..ee4f696a0 --- /dev/null +++ b/arch/x86/kvm/kvm_onhyperv.c @@ -0,0 +1,108 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * KVM L1 hypervisor optimizations on Hyper-V. + */ + +#include <linux/kvm_host.h> +#include <asm/mshyperv.h> + +#include "hyperv.h" +#include "kvm_onhyperv.h" + +static int kvm_fill_hv_flush_list_func(struct hv_guest_mapping_flush_list *flush, + void *data) +{ + struct kvm_tlb_range *range = data; + + return hyperv_fill_flush_guest_mapping_list(flush, range->start_gfn, + range->pages); +} + +static inline int hv_remote_flush_root_tdp(hpa_t root_tdp, + struct kvm_tlb_range *range) +{ + if (range) + return hyperv_flush_guest_mapping_range(root_tdp, + kvm_fill_hv_flush_list_func, (void *)range); + else + return hyperv_flush_guest_mapping(root_tdp); +} + +int hv_remote_flush_tlb_with_range(struct kvm *kvm, + struct kvm_tlb_range *range) +{ + struct kvm_arch *kvm_arch = &kvm->arch; + struct kvm_vcpu *vcpu; + int ret = 0, nr_unique_valid_roots; + unsigned long i; + hpa_t root; + + spin_lock(&kvm_arch->hv_root_tdp_lock); + + if (!VALID_PAGE(kvm_arch->hv_root_tdp)) { + nr_unique_valid_roots = 0; + + /* + * Flush all valid roots, and see if all vCPUs have converged + * on a common root, in which case future flushes can skip the + * loop and flush the common root. + */ + kvm_for_each_vcpu(i, vcpu, kvm) { + root = vcpu->arch.hv_root_tdp; + if (!VALID_PAGE(root) || root == kvm_arch->hv_root_tdp) + continue; + + /* + * Set the tracked root to the first valid root. Keep + * this root for the entirety of the loop even if more + * roots are encountered as a low effort optimization + * to avoid flushing the same (first) root again. + */ + if (++nr_unique_valid_roots == 1) + kvm_arch->hv_root_tdp = root; + + if (!ret) + ret = hv_remote_flush_root_tdp(root, range); + + /* + * Stop processing roots if a failure occurred and + * multiple valid roots have already been detected. + */ + if (ret && nr_unique_valid_roots > 1) + break; + } + + /* + * The optimized flush of a single root can't be used if there + * are multiple valid roots (obviously). + */ + if (nr_unique_valid_roots > 1) + kvm_arch->hv_root_tdp = INVALID_PAGE; + } else { + ret = hv_remote_flush_root_tdp(kvm_arch->hv_root_tdp, range); + } + + spin_unlock(&kvm_arch->hv_root_tdp_lock); + return ret; +} +EXPORT_SYMBOL_GPL(hv_remote_flush_tlb_with_range); + +int hv_remote_flush_tlb(struct kvm *kvm) +{ + return hv_remote_flush_tlb_with_range(kvm, NULL); +} +EXPORT_SYMBOL_GPL(hv_remote_flush_tlb); + +void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp) +{ + struct kvm_arch *kvm_arch = &vcpu->kvm->arch; + + if (kvm_x86_ops.tlb_remote_flush == hv_remote_flush_tlb) { + spin_lock(&kvm_arch->hv_root_tdp_lock); + vcpu->arch.hv_root_tdp = root_tdp; + if (root_tdp != kvm_arch->hv_root_tdp) + kvm_arch->hv_root_tdp = INVALID_PAGE; + spin_unlock(&kvm_arch->hv_root_tdp_lock); + } +} +EXPORT_SYMBOL_GPL(hv_track_root_tdp); |