Re: [Qemu-devel] [Qemu-ppc] [PATCH] target-ppc: Introduce hypervisor call H_GET_TCE

[Laurent Dufour <ldufour@linux.vnet.ibm.com>]

On 21/02/2014 10:29, Laurent Dufour wrote:
> This patch introduces the hypervisor call H_GET_TCE which is basically the
> reverse of H_PUT_TCE, as defined in the Power Architecture Platform
> Requirements (PAPR).
> 
> The hcall H_GET_TCE is required by the kdump kernel which is calling it to
> retrieve the TCE set up by the panicing kernel.

Hi,

Is there an issue with that patch ?

Regards,
Laurent.

> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
> ---
>  hw/ppc/spapr_iommu.c |   37 +++++++++++++++++++++++++++++++++++++
>  trace-events         |    1 +
>  2 files changed, 38 insertions(+)
> 
> diff --git a/hw/ppc/spapr_iommu.c b/hw/ppc/spapr_iommu.c
> index ef45f4f..d9fe946 100644
> --- a/hw/ppc/spapr_iommu.c
> +++ b/hw/ppc/spapr_iommu.c
> @@ -243,6 +243,42 @@ static target_ulong h_put_tce(PowerPCCPU *cpu, sPAPREnvironment *spapr,
>      return ret;
>  }
> 
> +static target_ulong get_tce_emu(sPAPRTCETable *tcet, target_ulong ioba,
> +                                target_ulong *tce)
> +{
> +    if (ioba >= tcet->window_size) {
> +        hcall_dprintf("spapr_iommu_get_tce on out-of-bounds IOBA 0x"
> +                      TARGET_FMT_lx "\n", ioba);
> +        return H_PARAMETER;
> +    }
> +
> +    *tce = tcet->table[ioba >> SPAPR_TCE_PAGE_SHIFT];
> +
> +    return H_SUCCESS;
> +}
> +
> +static target_ulong h_get_tce(PowerPCCPU *cpu, sPAPREnvironment *spapr,
> +                              target_ulong opcode, target_ulong *args)
> +{
> +    target_ulong liobn = args[0];
> +    target_ulong ioba = args[1];
> +    target_ulong tce = 0;
> +    target_ulong ret = H_PARAMETER;
> +    sPAPRTCETable *tcet = spapr_tce_find_by_liobn(liobn);
> +
> +    ioba &= ~(SPAPR_TCE_PAGE_SIZE - 1);
> +
> +    if (tcet) {
> +        ret = get_tce_emu(tcet, ioba, &tce);
> +        if (!ret) {
> +            args[0] = tce;
> +        }
> +    }
> +    trace_spapr_iommu_get(liobn, ioba, ret, tce);
> +
> +    return ret;
> +}
> +
>  int spapr_dma_dt(void *fdt, int node_off, const char *propname,
>                   uint32_t liobn, uint64_t window, uint32_t size)
>  {
> @@ -295,6 +331,7 @@ static void spapr_tce_table_class_init(ObjectClass *klass, void *data)
> 
>      /* hcall-tce */
>      spapr_register_hypercall(H_PUT_TCE, h_put_tce);
> +    spapr_register_hypercall(H_GET_TCE, h_get_tce);
>  }
> 
>  static TypeInfo spapr_tce_table_info = {
> diff --git a/trace-events b/trace-events
> index 0b3c1ac..5b306a0 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -1136,6 +1136,7 @@ xics_ics_eoi(int nr) "ics_eoi: irq %#x"
> 
>  # hw/ppc/spapr_iommu.c
>  spapr_iommu_put(uint64_t liobn, uint64_t ioba, uint64_t tce, uint64_t ret) "liobn=%"PRIx64" ioba=0x%"PRIx64" tce=0x%"PRIx64" ret=%"PRId64
> +spapr_iommu_get(uint64_t liobn, uint64_t ioba, uint64_t ret, uint64_t tce) "liobn=%"PRIx64" ioba=0x%"PRIx64" ret=%"PRId64" tce=0x%"PRIx64
>  spapr_iommu_xlate(uint64_t liobn, uint64_t ioba, uint64_t tce, unsigned perm, unsigned pgsize) "liobn=%"PRIx64" 0x%"PRIx64" -> 0x%"PRIx64" perm=%u mask=%x"
>  spapr_iommu_new_table(uint64_t liobn, void *tcet, void *table, int fd) "liobn=%"PRIx64" tcet=%p table=%p fd=%d"
> 
> 
>