[RESEND PATCH v5 1/6] powerpc: Document APIv2 KVM hcall spec for Hostwide counters

[Vaibhav Jain <vaibhav@linux.ibm.com>]

Update kvm-nested APIv2 documentation to include five new
Guest-State-Elements to fetch the hostwide counters. These counters are
per L1-Lpar and indicate the amount of Heap/Page-table memory allocated,
available and Page-table memory reclaimed for all L2-Guests active
instances

Cc: linux-doc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
---
Changelog

v5->resend:
* Rebase the patch to latest upstream kernel tree

v4->v5:
* None

v3->v4:
* Added reviewed by [ Bagas Sanjaya ]

v2->v3:
* Minor reword for the cumulative reclaim counter [ Gautam ]

v1->v2:
* Reworded section on GSID [Gautam]
---
 Documentation/arch/powerpc/kvm-nested.rst | 40 +++++++++++++++++------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/Documentation/arch/powerpc/kvm-nested.rst b/Documentation/arch/powerpc/kvm-nested.rst
index 5defd13cc6c1..574592505604 100644
--- a/Documentation/arch/powerpc/kvm-nested.rst
+++ b/Documentation/arch/powerpc/kvm-nested.rst
@@ -208,13 +208,9 @@ associated values for each ID in the GSB::
       flags:
          Bit 0: getGuestWideState: Request state of the Guest instead
            of an individual VCPU.
-         Bit 1: takeOwnershipOfVcpuState Indicate the L1 is taking
-           over ownership of the VCPU state and that the L0 can free
-           the storage holding the state. The VCPU state will need to
-           be returned to the Hypervisor via H_GUEST_SET_STATE prior
-           to H_GUEST_RUN_VCPU being called for this VCPU. The data
-           returned in the dataBuffer is in a Hypervisor internal
-           format.
+         Bit 1: getHostWideState: Request stats of the Host. This causes
+           the guestId and vcpuId parameters to be ignored and attempting
+           to get the VCPU/Guest state will cause an error.
          Bits 2-63: Reserved
       guestId: ID obtained from H_GUEST_CREATE
       vcpuId: ID of the vCPU pass to H_GUEST_CREATE_VCPU
@@ -406,9 +402,10 @@ the partition like the timebase offset and partition scoped page
 table information.
 
 +--------+-------+----+--------+----------------------------------+
-|   ID   | Size  | RW | Thread | Details                          |
-|        | Bytes |    | Guest  |                                  |
-|        |       |    | Scope  |                                  |
+|   ID   | Size  | RW |(H)ost  | Details                          |
+|        | Bytes |    |(G)uest |                                  |
+|        |       |    |(T)hread|                                  |
+|        |       |    |Scope   |                                  |
 +========+=======+====+========+==================================+
 | 0x0000 |       | RW |   TG   | NOP element                      |
 +--------+-------+----+--------+----------------------------------+
@@ -434,6 +431,29 @@ table information.
 |        |       |    |        |- 0x8 Table size.                 |
 +--------+-------+----+--------+----------------------------------+
 | 0x0007-|       |    |        | Reserved                         |
+| 0x07FF |       |    |        |                                  |
++--------+-------+----+--------+----------------------------------+
+| 0x0800 | 0x08  | R  |   H    | Current usage in bytes of the    |
+|        |       |    |        | L0's Guest Management Space      |
+|        |       |    |        | for an L1-Lpar.                  |
++--------+-------+----+--------+----------------------------------+
+| 0x0801 | 0x08  | R  |   H    | Max bytes available in the       |
+|        |       |    |        | L0's Guest Management Space for  |
+|        |       |    |        | an L1-Lpar                       |
++--------+-------+----+--------+----------------------------------+
+| 0x0802 | 0x08  | R  |   H    | Current usage in bytes of the    |
+|        |       |    |        | L0's Guest Page Table Management |
+|        |       |    |        | Space for an L1-Lpar             |
++--------+-------+----+--------+----------------------------------+
+| 0x0803 | 0x08  | R  |   H    | Max bytes available in the L0's  |
+|        |       |    |        | Guest Page Table Management      |
+|        |       |    |        | Space for an L1-Lpar             |
++--------+-------+----+--------+----------------------------------+
+| 0x0804 | 0x08  | R  |   H    | Cumulative Reclaimed bytes from  |
+|        |       |    |        | L0 Guest's Page Table Management |
+|        |       |    |        | Space due to overcommit          |
++--------+-------+----+--------+----------------------------------+
+| 0x0805-|       |    |        | Reserved                         |
 | 0x0BFF |       |    |        |                                  |
 +--------+-------+----+--------+----------------------------------+
 | 0x0C00 | 0x10  | RW |   T    |Run vCPU Input Buffer:            |
-- 
2.49.0