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| author | Gavin Shan <gshan@redhat.com> | 2022-11-10 18:49:10 +0800 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2022-11-10 13:11:58 +0000 |
| commit | 86bdf3ebcfe1ded055282536fecce13001874740 (patch) | |
| tree | a5d026afbabe42b47025a8f9fdcec9e652898d47 /include | |
| parent | e8a18565e59303ac12c626a161d72bd890bd2062 (diff) | |
| download | linux-stable-86bdf3ebcfe1ded055282536fecce13001874740.tar.gz linux-stable-86bdf3ebcfe1ded055282536fecce13001874740.tar.bz2 linux-stable-86bdf3ebcfe1ded055282536fecce13001874740.zip | |
KVM: Support dirty ring in conjunction with bitmap
ARM64 needs to dirty memory outside of a VCPU context when VGIC/ITS is
enabled. It's conflicting with that ring-based dirty page tracking always
requires a running VCPU context.
Introduce a new flavor of dirty ring that requires the use of both VCPU
dirty rings and a dirty bitmap. The expectation is that for non-VCPU
sources of dirty memory (such as the VGIC/ITS on arm64), KVM writes to
the dirty bitmap. Userspace should scan the dirty bitmap before migrating
the VM to the target.
Use an additional capability to advertise this behavior. The newly added
capability (KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP) can't be enabled before
KVM_CAP_DIRTY_LOG_RING_ACQ_REL on ARM64. In this way, the newly added
capability is treated as an extension of KVM_CAP_DIRTY_LOG_RING_ACQ_REL.
Suggested-by: Marc Zyngier <maz@kernel.org>
Suggested-by: Peter Xu <peterx@redhat.com>
Co-developed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110104914.31280-4-gshan@redhat.com
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/kvm_dirty_ring.h | 7 | ||||
| -rw-r--r-- | include/linux/kvm_host.h | 1 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 1 |
3 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/kvm_dirty_ring.h b/include/linux/kvm_dirty_ring.h index 199ead37b104..4862c98d80d3 100644 --- a/include/linux/kvm_dirty_ring.h +++ b/include/linux/kvm_dirty_ring.h @@ -37,6 +37,11 @@ static inline u32 kvm_dirty_ring_get_rsvd_entries(void) return 0; } +static inline bool kvm_use_dirty_bitmap(struct kvm *kvm) +{ + return true; +} + static inline int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring, int index, u32 size) { @@ -67,6 +72,8 @@ static inline void kvm_dirty_ring_free(struct kvm_dirty_ring *ring) #else /* CONFIG_HAVE_KVM_DIRTY_RING */ int kvm_cpu_dirty_log_size(void); +bool kvm_use_dirty_bitmap(struct kvm *kvm); +bool kvm_arch_allow_write_without_running_vcpu(struct kvm *kvm); u32 kvm_dirty_ring_get_rsvd_entries(void); int kvm_dirty_ring_alloc(struct kvm_dirty_ring *ring, int index, u32 size); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 648d663f32c4..db83f63f4e61 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -779,6 +779,7 @@ struct kvm { pid_t userspace_pid; unsigned int max_halt_poll_ns; u32 dirty_ring_size; + bool dirty_ring_with_bitmap; bool vm_bugged; bool vm_dead; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 0d5d4419139a..c87b5882d7ae 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1178,6 +1178,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_S390_ZPCI_OP 221 #define KVM_CAP_S390_CPU_TOPOLOGY 222 #define KVM_CAP_DIRTY_LOG_RING_ACQ_REL 223 +#define KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP 224 #ifdef KVM_CAP_IRQ_ROUTING |