Re: [PATCH v2 1/2] arch/powerpc/kvm: Add DPDES support in helper library for Guest state buffer

Nicholas Piggin
2024-06-06T02:59:42Z

On Wed Jun 5, 2024 at 9:39 PM AEST, Gautam Menghani wrote:
> Add support for using DPDES in the library for using guest state
> buffers. DPDES support is needed for enabling usage of doorbells in a
> L2 KVM on PAPR guest.
>

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

> Fixes: 6ccbbc33f06a ("KVM: PPC: Add helper library for Guest State Buffers")
> Cc: stable@vger.kernel.org # v6.7
> Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
> ---
> Documentation/arch/powerpc/kvm-nested.rst | 4 +++-
> arch/powerpc/include/asm/guest-state-buffer.h | 3 ++-
> arch/powerpc/include/asm/kvm_book3s.h | 1 +
> arch/powerpc/kvm/book3s_hv_nestedv2.c | 7 +++++++
> arch/powerpc/kvm/test-guest-state-buffer.c | 2 +-
> 5 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/arch/powerpc/kvm-nested.rst b/Documentation/arch/powerpc/kvm-nested.rst
> index 630602a8aa00..5defd13cc6c1 100644
> --- a/Documentation/arch/powerpc/kvm-nested.rst
> +++ b/Documentation/arch/powerpc/kvm-nested.rst
> @@ -546,7 +546,9 @@ table information.
> +--------+-------+----+--------+----------------------------------+
> | 0x1052 | 0x08 | RW | T | CTRL |
> +--------+-------+----+--------+----------------------------------+
> -| 0x1053-| | | | Reserved |
> +| 0x1053 | 0x08 | RW | T | DPDES |
> ++--------+-------+----+--------+----------------------------------+
> +| 0x1054-| | | | Reserved |
> | 0x1FFF | | | | |
> +--------+-------+----+--------+----------------------------------+
> | 0x2000 | 0x04 | RW | T | CR |
> diff --git a/arch/powerpc/include/asm/guest-state-buffer.h b/arch/powerpc/include/asm/guest-state-buffer.h
> index 808149f31576..d107abe1468f 100644
> --- a/arch/powerpc/include/asm/guest-state-buffer.h
> +++ b/arch/powerpc/include/asm/guest-state-buffer.h
> @@ -81,6 +81,7 @@
> #define KVMPPC_GSID_HASHKEYR 0x1050
> #define KVMPPC_GSID_HASHPKEYR 0x1051
> #define KVMPPC_GSID_CTRL 0x1052
> +#define KVMPPC_GSID_DPDES 0x1053
>
> #define KVMPPC_GSID_CR 0x2000
> #define KVMPPC_GSID_PIDR 0x2001
> @@ -110,7 +111,7 @@
> #define KVMPPC_GSE_META_COUNT (KVMPPC_GSE_META_END - KVMPPC_GSE_META_START + 1)
>
> #define KVMPPC_GSE_DW_REGS_START KVMPPC_GSID_GPR(0)
> -#define KVMPPC_GSE_DW_REGS_END KVMPPC_GSID_CTRL
> +#define KVMPPC_GSE_DW_REGS_END KVMPPC_GSID_DPDES
> #define KVMPPC_GSE_DW_REGS_COUNT \
> (KVMPPC_GSE_DW_REGS_END - KVMPPC_GSE_DW_REGS_START + 1)
>
> diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
> index 3e1e2a698c9e..10618622d7ef 100644
> --- a/arch/powerpc/include/asm/kvm_book3s.h
> +++ b/arch/powerpc/include/asm/kvm_book3s.h
> @@ -594,6 +594,7 @@ static inline u##size kvmppc_get_##reg(struct kvm_vcpu *vcpu) \
>
>
> KVMPPC_BOOK3S_VCORE_ACCESSOR(vtb, 64, KVMPPC_GSID_VTB)
> +KVMPPC_BOOK3S_VCORE_ACCESSOR(dpdes, 64, KVMPPC_GSID_DPDES)
> KVMPPC_BOOK3S_VCORE_ACCESSOR_GET(arch_compat, 32, KVMPPC_GSID_LOGICAL_PVR)
> KVMPPC_BOOK3S_VCORE_ACCESSOR_GET(lpcr, 64, KVMPPC_GSID_LPCR)
> KVMPPC_BOOK3S_VCORE_ACCESSOR_SET(tb_offset, 64, KVMPPC_GSID_TB_OFFSET)
> diff --git a/arch/powerpc/kvm/book3s_hv_nestedv2.c b/arch/powerpc/kvm/book3s_hv_nestedv2.c
> index 8e6f5355f08b..36863fff2a99 100644
> --- a/arch/powerpc/kvm/book3s_hv_nestedv2.c
> +++ b/arch/powerpc/kvm/book3s_hv_nestedv2.c
> @@ -311,6 +311,10 @@ static int gs_msg_ops_vcpu_fill_info(struct kvmppc_gs_buff *gsb,
> rc = kvmppc_gse_put_u64(gsb, iden,
> vcpu->arch.vcore->vtb);
> break;
> + case KVMPPC_GSID_DPDES:
> + rc = kvmppc_gse_put_u64(gsb, iden,
> + vcpu->arch.vcore->dpdes);
> + break;
> case KVMPPC_GSID_LPCR:
> rc = kvmppc_gse_put_u64(gsb, iden,
> vcpu->arch.vcore->lpcr);
> @@ -543,6 +547,9 @@ static int gs_msg_ops_vcpu_refresh_info(struct kvmppc_gs_msg *gsm,
> case KVMPPC_GSID_VTB:
> vcpu->arch.vcore->vtb = kvmppc_gse_get_u64(gse);
> break;
> + case KVMPPC_GSID_DPDES:
> + vcpu->arch.vcore->dpdes = kvmppc_gse_get_u64(gse);
> + break;
> case KVMPPC_GSID_LPCR:
> vcpu->arch.vcore->lpcr = kvmppc_gse_get_u64(gse);
> break;
> diff --git a/arch/powerpc/kvm/test-guest-state-buffer.c b/arch/powerpc/kvm/test-guest-state-buffer.c
> index 4720b8dc8837..2571ccc618c9 100644
> --- a/arch/powerpc/kvm/test-guest-state-buffer.c
> +++ b/arch/powerpc/kvm/test-guest-state-buffer.c
> @@ -151,7 +151,7 @@ static void test_gs_bitmap(struct kunit *test)
> i++;
> }
>
> - for (u16 iden = KVMPPC_GSID_GPR(0); iden <= KVMPPC_GSID_CTRL; iden++) {
> + for (u16 iden = KVMPPC_GSID_GPR(0); iden <= KVMPPC_GSE_DW_REGS_END; iden++) {
> kvmppc_gsbm_set(&gsbm, iden);
> kvmppc_gsbm_set(&gsbm1, iden);
> KUNIT_EXPECT_TRUE(test, kvmppc_gsbm_test(&gsbm, iden));