Excerpts from Haren Myneni's message of January 22, 2022 6:00 am:
>
> The hypervisor provides the available VAS GZIP capabilities such
> as default or QoS window type and the target available credits in
> each type. This patch creates sysfs entries and exports the target,
> used and the available credits for each feature.
>
> This interface can be used by the user space to determine the credits
> usage or to set the target credits in the case of QoS type (for DLPAR).
>
> /sys/devices/vas/vas0/gzip/def_caps: (default GZIP capabilities)
> avail_creds /* Available credits to use */
> target_creds /* Total credits available. Can be
> /* changed with DLPAR operation */
> used_creds /* Used credits */
>
> /sys/devices/vas/vas0/gzip/qos_caps (QoS GZIP capabilities)
> avail_creds
> target_creds
> used_creds
Can we not use these abbreviations in sysfs?
In the code it's one thing (I still don't prefer them but that's up to
you), but we should be a bit better in external ABIs. Can we also get a
better description of the difference between available credits and
target credits? They both appear to be credits available.
default_capabilities
nr_available_credits
nr_target_credits
nr_used_credits
qos_capabilities
...
Keeping this description in the tree rather than just in the changelog
would be nice too.
>
> Signed-off-by: Haren Myneni <ha...@linux.ibm.com>
> ---
> arch/powerpc/platforms/pseries/Makefile | 2 +-
> arch/powerpc/platforms/pseries/vas-sysfs.c | 218 +++++++++++++++++++++
> arch/powerpc/platforms/pseries/vas.c | 6 +
> arch/powerpc/platforms/pseries/vas.h | 6 +
> 4 files changed, 231 insertions(+), 1 deletion(-)
> create mode 100644 arch/powerpc/platforms/pseries/vas-sysfs.c
>
> diff --git a/arch/powerpc/platforms/pseries/Makefile
> b/arch/powerpc/platforms/pseries/Makefile
> index ee60b59024b4..29b522d2c755 100644
> --- a/arch/powerpc/platforms/pseries/Makefile
> +++ b/arch/powerpc/platforms/pseries/Makefile
> @@ -29,6 +29,6 @@ obj-$(CONFIG_PPC_SVM) += svm.o
> obj-$(CONFIG_FA_DUMP) += rtas-fadump.o
>
> obj-$(CONFIG_SUSPEND) += suspend.o
> -obj-$(CONFIG_PPC_VAS) += vas.o
> +obj-$(CONFIG_PPC_VAS) += vas.o vas-sysfs.o
>
> obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += cc_platform.o
> diff --git a/arch/powerpc/platforms/pseries/vas-sysfs.c
> b/arch/powerpc/platforms/pseries/vas-sysfs.c
> new file mode 100644
> index 000000000000..f7609cdef8f8
> --- /dev/null
> +++ b/arch/powerpc/platforms/pseries/vas-sysfs.c
> @@ -0,0 +1,218 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright 2016-17 IBM Corp.
Seems to have suffered a copy-paste problem.
> + /*
> + * The hypervisor does not expose multiple VAS instances, but can
> + * see multiple VAS instances on PowerNV. So create 'vas0' directory
> + * on PowerVM.
powernv / pseries when you're talking about the APIs or Linux
implementation (or you can use OPAL / PAPR for APIs specifically too).
Thanks,
Nick
> + */
> + pseries_vas_kobj = kobject_create_and_add("vas0",
> + &vas_miscdev.this_device->kobj);
> + if (!pseries_vas_kobj) {
> + pr_err("Failed to create VAS sysfs entry\n");
> + return -ENOMEM;
> + }
> +
> + if ((vas_caps->feat_type & VAS_GZIP_QOS_FEAT_BIT) ||
> + (vas_caps->feat_type & VAS_GZIP_DEF_FEAT_BIT)) {
> + gzip_caps_kobj = kobject_create_and_add("gzip",
> + pseries_vas_kobj);
> + if (!gzip_caps_kobj) {
> + pr_err("Failed to create VAS GZIP capability entry\n");
> + kobject_put(pseries_vas_kobj);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +#else
> +int sysfs_add_vas_caps(struct vas_cop_feat_caps *caps)
> +{
> + return 0;
> +}
> +
> +int __init sysfs_pseries_vas_init(struct vas_all_caps *vas_caps)
> +{
> + return 0;
> +}
> +#endif
> diff --git a/arch/powerpc/platforms/pseries/vas.c
> b/arch/powerpc/platforms/pseries/vas.c
> index 75ccd0a599ec..32098e4a2786 100644
> --- a/arch/powerpc/platforms/pseries/vas.c
> +++ b/arch/powerpc/platforms/pseries/vas.c
> @@ -560,6 +560,10 @@ static int __init get_vas_capabilities(u8 feat, enum
> vas_cop_feat_type type,
> }
> }
>
> + rc = sysfs_add_vas_caps(caps);
> + if (rc)
> + return rc;
> +
> copypaste_feat = true;
>
> return 0;
> @@ -843,6 +847,8 @@ static int __init pseries_vas_init(void)
> caps_all.descriptor = be64_to_cpu(hv_caps->descriptor);
> caps_all.feat_type = be64_to_cpu(hv_caps->feat_type);
>
> + sysfs_pseries_vas_init(&caps_all);
> +
> hv_cop_caps = kmalloc(sizeof(*hv_cop_caps), GFP_KERNEL);
> if (!hv_cop_caps) {
> rc = -ENOMEM;
> diff --git a/arch/powerpc/platforms/pseries/vas.h
> b/arch/powerpc/platforms/pseries/vas.h
> index 8ce9b84693e8..bc393bd74030 100644
> --- a/arch/powerpc/platforms/pseries/vas.h
> +++ b/arch/powerpc/platforms/pseries/vas.h
> @@ -24,6 +24,9 @@
> #define VAS_COPY_PASTE_USER_MODE 0x00000001
> #define VAS_COP_OP_USER_MODE 0x00000010
>
> +#define VAS_GZIP_QOS_CAPABILITIES 0x56516F73477A6970
> +#define VAS_GZIP_DEFAULT_CAPABILITIES 0x56446566477A6970
> +
> /*
> * Co-processor feature - GZIP QoS windows or GZIP default windows
> */
> @@ -120,4 +123,7 @@ struct pseries_vas_window {
> char *name;
> int fault_virq;
> };
> +
> +int sysfs_add_vas_caps(struct vas_cop_feat_caps *caps);
> +int __init sysfs_pseries_vas_init(struct vas_all_caps *vas_caps);
> #endif /* _VAS_H */
> --
> 2.27.0
>
>
>
