[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v3] ppc/spapr: Add support for implement support for H_SCM_HE
From: |
Greg Kurz |
Subject: |
Re: [PATCH v3] ppc/spapr: Add support for implement support for H_SCM_HEALTH |
Date: |
Fri, 2 Apr 2021 17:12:17 +0200 |
On Fri, 2 Apr 2021 15:51:28 +0530
Vaibhav Jain <vaibhav@linux.ibm.com> wrote:
> Add support for H_SCM_HEALTH hcall described at [1] for spapr
> nvdimms. This enables guest to detect the 'unarmed' status of a
> specific spapr nvdimm identified by its DRC and if its unarmed, mark
> the region backed by the nvdimm as read-only.
>
> The patch adds h_scm_health() to handle the H_SCM_HEALTH hcall which
> returns two 64-bit bitmaps (health bitmap, health bitmap mask) derived
> from 'struct nvdimm->unarmed' member.
>
> Linux kernel side changes to enable handling of 'unarmed' nvdimms for
> ppc64 are proposed at [2].
>
> References:
> [1] "Hypercall Op-codes (hcalls)"
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/powerpc/papr_hcalls.rst#n220
> [2] "powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe"
>
> https://lore.kernel.org/linux-nvdimm/20210329113103.476760-1-vaibhav@linux.ibm.com/
>
> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
> ---
> Changelog
>
> v3:
> * Switched to PPC_BIT macro for definitions of the health bits. [ Greg, David
> ]
> * Updated h_scm_health() to use a const uint64_t to denote supported
> bits in 'hbitmap_mask'.
> * Fixed an error check for drc->dev to return H_PARAMETER in case nvdimm
> is not yet plugged in [ Greg ]
> * Fixed an wrong error check for ensuring drc and drc-type are correct
> [ Greg ]
>
> v2:
> * Added a check for drc->dev to ensure that the dimm is plugged in
> when servicing H_SCM_HEALTH. [ Shiva ]
> * Instead of accessing the 'nvdimm->unarmed' member directly use the
> object_property_get_bool accessor to fetch it. [ Shiva ]
> * Update the usage of PAPR_PMEM_UNARMED* macros [ Greg ]
> * Updated patch description reference#1 to point appropriate section
> in the documentation. [ Greg ]
> ---
Reviewed-by: Greg Kurz <groug@kaod.org>
> hw/ppc/spapr_nvdimm.c | 36 ++++++++++++++++++++++++++++++++++++
> include/hw/ppc/spapr.h | 3 ++-
> 2 files changed, 38 insertions(+), 1 deletion(-)
>
> diff --git a/hw/ppc/spapr_nvdimm.c b/hw/ppc/spapr_nvdimm.c
> index b46c36917c..252204e25f 100644
> --- a/hw/ppc/spapr_nvdimm.c
> +++ b/hw/ppc/spapr_nvdimm.c
> @@ -31,6 +31,10 @@
> #include "qemu/range.h"
> #include "hw/ppc/spapr_numa.h"
>
> +/* DIMM health bitmap bitmap indicators. Taken from kernel's papr_scm.c */
> +/* SCM device is unable to persist memory contents */
> +#define PAPR_PMEM_UNARMED PPC_BIT(0)
> +
> bool spapr_nvdimm_validate(HotplugHandler *hotplug_dev, NVDIMMDevice *nvdimm,
> uint64_t size, Error **errp)
> {
> @@ -467,6 +471,37 @@ static target_ulong h_scm_unbind_all(PowerPCCPU *cpu,
> SpaprMachineState *spapr,
> return H_SUCCESS;
> }
>
> +static target_ulong h_scm_health(PowerPCCPU *cpu, SpaprMachineState *spapr,
> + target_ulong opcode, target_ulong *args)
> +{
> +
> + NVDIMMDevice *nvdimm;
> + uint64_t hbitmap = 0;
> + uint32_t drc_index = args[0];
> + SpaprDrc *drc = spapr_drc_by_index(drc_index);
> + const uint64_t hbitmap_mask = PAPR_PMEM_UNARMED;
> +
> +
> + /* Ensure that the drc is valid & is valid PMEM dimm and is plugged in */
> + if (!drc || !drc->dev ||
> + spapr_drc_type(drc) != SPAPR_DR_CONNECTOR_TYPE_PMEM) {
> + return H_PARAMETER;
> + }
> +
> + nvdimm = NVDIMM(drc->dev);
> +
> + /* Update if the nvdimm is unarmed and send its status via health
> bitmaps */
> + if (object_property_get_bool(OBJECT(nvdimm), NVDIMM_UNARMED_PROP, NULL))
> {
> + hbitmap |= PAPR_PMEM_UNARMED;
> + }
> +
> + /* Update the out args with health bitmap/mask */
> + args[0] = hbitmap;
> + args[1] = hbitmap_mask;
> +
> + return H_SUCCESS;
> +}
> +
> static void spapr_scm_register_types(void)
> {
> /* qemu/scm specific hcalls */
> @@ -475,6 +510,7 @@ static void spapr_scm_register_types(void)
> spapr_register_hypercall(H_SCM_BIND_MEM, h_scm_bind_mem);
> spapr_register_hypercall(H_SCM_UNBIND_MEM, h_scm_unbind_mem);
> spapr_register_hypercall(H_SCM_UNBIND_ALL, h_scm_unbind_all);
> + spapr_register_hypercall(H_SCM_HEALTH, h_scm_health);
> }
>
> type_init(spapr_scm_register_types)
> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
> index 47cebaf3ac..6e1eafb05d 100644
> --- a/include/hw/ppc/spapr.h
> +++ b/include/hw/ppc/spapr.h
> @@ -538,8 +538,9 @@ struct SpaprMachineState {
> #define H_SCM_BIND_MEM 0x3EC
> #define H_SCM_UNBIND_MEM 0x3F0
> #define H_SCM_UNBIND_ALL 0x3FC
> +#define H_SCM_HEALTH 0x400
>
> -#define MAX_HCALL_OPCODE H_SCM_UNBIND_ALL
> +#define MAX_HCALL_OPCODE H_SCM_HEALTH
>
> /* The hcalls above are standardized in PAPR and implemented by pHyp
> * as well.