[RFC PATCH V4 00/12] x86/Hyper-V: Add Hyper-V Isolation VM support

From: Tianyu Lan
Date: Wed Jul 07 2021 - 11:35:13 EST


From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>

Hyper-V provides two kinds of Isolation VMs. VBS(Virtualization-based
security) and AMD SEV-SNP unenlightened Isolation VMs. This patchset
is to add support for these Isolation VM support in Linux.

The memory of these vms are encrypted and host can't access guest
memory directly. Hyper-V provides new host visibility hvcall and
the guest needs to call new hvcall to mark memory visible to host
before sharing memory with host. For security, all network/storage
stack memory should not be shared with host and so there is bounce
buffer requests.

Vmbus channel ring buffer already plays bounce buffer role because
all data from/to host needs to copy from/to between the ring buffer
and IO stack memory. So mark vmbus channel ring buffer visible.

There are two exceptions - packets sent by vmbus_sendpacket_
pagebuffer() and vmbus_sendpacket_mpb_desc(). These packets
contains IO stack memory address and host will access these memory.
So add allocation bounce buffer support in vmbus for these packets.

For SNP isolation VM, guest needs to access the shared memory via
extra address space which is specified by Hyper-V CPUID HYPERV_CPUID_
ISOLATION_CONFIG. The access physical address of the shared memory
should be bounce buffer memory GPA plus with shared_gpa_boundary
reported by CPUID.

Change since v3:
- Add interface set_memory_decrypted_map() to decrypt memory and
map bounce buffer in extra address space
- Remove swiotlb remap function and store the remap address
returned by set_memory_decrypted_map() in swiotlb mem data structure.
- Introduce hv_set_mem_enc() to make code more readable in the __set_memory_enc_dec().

Change since v2:
- Remove not UIO driver in Isolation VM patch
- Use vmap_pfn() to replace ioremap_page_range function in
order to avoid exposing symbol ioremap_page_range() and
ioremap_page_range()
- Call hv set mem host visibility hvcall in set_memory_encrypted/decrypted()
- Enable swiotlb force mode instead of adding Hyper-V dma map/unmap hook
- Fix code style

Tianyu Lan (12):
x86/HV: Initialize shared memory boundary in the Isolation VM.
x86/HV: Add new hvcall guest address host visibility support
HV: Mark vmbus ring buffer visible to host in Isolation VM
HV: Add Write/Read MSR registers via ghcb page
HV: Add ghcb hvcall support for SNP VM
HV/Vmbus: Add SNP support for VMbus channel initiate message
HV/Vmbus: Initialize VMbus ring buffer for Isolation VM
x86/Swiotlb/HV: Add Swiotlb bounce buffer remap function for HV IVM
HV/IOMMU: Enable swiotlb bounce buffer for Isolation VM
HV/Netvsc: Add Isolation VM support for netvsc driver
HV/Storvsc: Add Isolation VM support for storvsc driver
x86/HV: Not set memory decrypted/encrypted during kexec alloc/free
page in IVM

arch/x86/hyperv/Makefile | 2 +-
arch/x86/hyperv/hv_init.c | 25 +--
arch/x86/hyperv/ivm.c | 299 +++++++++++++++++++++++++++++
arch/x86/include/asm/hyperv-tlfs.h | 18 ++
arch/x86/include/asm/mshyperv.h | 84 +++++++-
arch/x86/include/asm/set_memory.h | 2 +
arch/x86/include/asm/sev-es.h | 4 +
arch/x86/kernel/cpu/mshyperv.c | 5 +
arch/x86/kernel/machine_kexec_64.c | 5 +-
arch/x86/kernel/sev-es-shared.c | 21 +-
arch/x86/mm/pat/set_memory.c | 34 +++-
arch/x86/xen/pci-swiotlb-xen.c | 3 +-
drivers/hv/Kconfig | 1 +
drivers/hv/channel.c | 48 ++++-
drivers/hv/connection.c | 71 ++++++-
drivers/hv/hv.c | 129 +++++++++----
drivers/hv/hyperv_vmbus.h | 3 +
drivers/hv/ring_buffer.c | 84 ++++++--
drivers/hv/vmbus_drv.c | 3 +
drivers/iommu/hyperv-iommu.c | 62 ++++++
drivers/net/hyperv/hyperv_net.h | 6 +
drivers/net/hyperv/netvsc.c | 144 +++++++++++++-
drivers/net/hyperv/rndis_filter.c | 2 +
drivers/scsi/storvsc_drv.c | 68 ++++++-
include/asm-generic/hyperv-tlfs.h | 1 +
include/asm-generic/mshyperv.h | 53 ++++-
include/linux/hyperv.h | 16 ++
include/linux/swiotlb.h | 4 +
kernel/dma/swiotlb.c | 11 +-
29 files changed, 1097 insertions(+), 111 deletions(-)
create mode 100644 arch/x86/hyperv/ivm.c

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2.25.1