aboutsummaryrefslogtreecommitdiff
path: root/docs/specs/ppc-spapr-uv-hcalls.txt
diff options
context:
space:
mode:
authorLeonardo Garcia <lagarcia@br.ibm.com>2022-01-18 12:56:30 +0100
committerCédric Le Goater <clg@kaod.org>2022-01-18 12:56:30 +0100
commitdedc5d79dae59562b2311301d27ecbf2234acf8a (patch)
tree6434b80e8a34a94f2098d25c9f2b32a68d4f01ad /docs/specs/ppc-spapr-uv-hcalls.txt
parent2084b44d7afa2e604c52a31ee89f46a01835131b (diff)
Rename ppc-spapr-uv-hcalls.txt to ppc-spapr-uv-hcalls.rst.
Signed-off-by: Leonardo Garcia <lagarcia@br.ibm.com> Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com> Message-Id: <ea1554e3a02e093eaa64d1260faf01d525c9ecdc.1642446876.git.lagarcia@br.ibm.com> Signed-off-by: Cédric Le Goater <clg@kaod.org>
Diffstat (limited to 'docs/specs/ppc-spapr-uv-hcalls.txt')
-rw-r--r--docs/specs/ppc-spapr-uv-hcalls.txt89
1 files changed, 0 insertions, 89 deletions
diff --git a/docs/specs/ppc-spapr-uv-hcalls.txt b/docs/specs/ppc-spapr-uv-hcalls.txt
deleted file mode 100644
index a00288deb3..0000000000
--- a/docs/specs/ppc-spapr-uv-hcalls.txt
+++ /dev/null
@@ -1,89 +0,0 @@
-===================================
-Hypervisor calls and the Ultravisor
-===================================
-
-On PPC64 systems supporting Protected Execution Facility (PEF), system memory
-can be placed in a secured region where only an ultravisor running in firmware
-can provide access to. pSeries guests on such systems can communicate with
-the ultravisor (via ultracalls) to switch to a secure virtual machine (SVM) mode
-where the guest's memory is relocated to this secured region, making its memory
-inaccessible to normal processes/guests running on the host.
-
-The various ultracalls/hypercalls relating to SVM mode are currently only
-documented internally, but are planned for direct inclusion into the Linux on
-Power Architecture Reference document ([LoPAR]_). An internal ACR has been filed
-to reserve a hypercall number range specific to this use case to avoid any
-future conflicts with the IBM internally maintained Power Architecture Platform
-Reference (PAPR+) documentation specification. This document summarizes some of
-these details as they relate to QEMU.
-
-Hypercalls needed by the ultravisor
-===================================
-
-Switching to SVM mode involves a number of hcalls issued by the ultravisor to
-the hypervisor to orchestrate the movement of guest memory to secure memory and
-various other aspects of the SVM mode. Numbers are assigned for these hcalls
-within the reserved range ``0xEF00-0xEF80``. The below documents the hcalls
-relevant to QEMU.
-
-``H_TPM_COMM`` (``0xef10``)
----------------------------
-
-SVM file systems are encrypted using a symmetric key. This key is then
-wrapped/encrypted using the public key of a trusted system which has the private
-key stored in the system's TPM. An Ultravisor will use this hcall to
-unwrap/unseal the symmetric key using the system's TPM device or a TPM Resource
-Manager associated with the device.
-
-The Ultravisor sets up a separate session key with the TPM in advance during
-host system boot. All sensitive in and out values will be encrypted using the
-session key. Though the hypervisor will see the in and out buffers in raw form,
-any sensitive contents will generally be encrypted using this session key.
-
-Arguments:
-
- ``r3``: ``H_TPM_COMM`` (``0xef10``)
-
- ``r4``: ``TPM`` operation, one of:
-
- ``TPM_COMM_OP_EXECUTE`` (``0x1``): send a request to a TPM and receive a
- response, opening a new TPM session if one has not already been opened.
-
- ``TPM_COMM_OP_CLOSE_SESSION`` (``0x2``): close the existing TPM session, if
- any.
-
- ``r5``: ``in_buffer``, guest physical address of buffer containing the
- request. Caller may use the same address for both request and response.
-
- ``r6``: ``in_size``, size of the in buffer. Must be less than or equal to
- 4 KB.
-
- ``r7``: ``out_buffer``, guest physical address of buffer to store the
- response. Caller may use the same address for both request and response.
-
- ``r8``: ``out_size``, size of the out buffer. Must be at least 4 KB, as this
- is the maximum request/response size supported by most TPM implementations,
- including the TPM Resource Manager in the linux kernel.
-
-Return values:
-
- ``r3``: one of the following values:
-
- ``H_Success``: request processed successfully.
-
- ``H_PARAMETER``: invalid TPM operation.
-
- ``H_P2``: ``in_buffer`` is invalid.
-
- ``H_P3``: ``in_size`` is invalid.
-
- ``H_P4``: ``out_buffer`` is invalid.
-
- ``H_P5``: ``out_size`` is invalid.
-
- ``H_RESOURCE``: problem communicating with TPM.
-
- ``H_FUNCTION``: TPM access is not currently allowed/configured.
-
- ``r4``: For ``TPM_COMM_OP_EXECUTE``, the size of the response will be stored
- here upon success.