On Mon, 2021-05-10 at 16:13 +1000, Nicholas Piggin wrote: > Excerpts from Haren Myneni's message of April 18, 2021 7:08 am: > > pHyp provides various VAS capabilities such as GZIP default and QoS > > capabilities which are used to determine total number of credits > > available in LPAR, maximum window credits, maximum LPAR credits, > > whether usermode copy/paste is supported, and etc. > > > > So first retrieve overall vas capabilities using > > H_QUERY_VAS_CAPABILITIES HCALL which tells the specific features > > that > > are available. Then retrieve the specific capabilities by using the > > feature type in H_QUERY_VAS_CAPABILITIES HCALL. > > > > pHyp supports only GZIP default and GZIP QoS capabilities right > > now. > > Changelog and title could use a bit of work. > > > Signed-off-by: Haren Myneni <haren@xxxxxxxxxxxxx> > > --- > > arch/powerpc/platforms/pseries/vas.c | 130 > > +++++++++++++++++++++++++++ > > 1 file changed, 130 insertions(+) > > > > diff --git a/arch/powerpc/platforms/pseries/vas.c > > b/arch/powerpc/platforms/pseries/vas.c > > index 06960151477c..35946fb02995 100644 > > --- a/arch/powerpc/platforms/pseries/vas.c > > +++ b/arch/powerpc/platforms/pseries/vas.c > > @@ -30,6 +30,13 @@ > > /* phyp allows one credit per window right now */ > > #define DEF_WIN_CREDS 1 > > > > +static struct vas_all_capabs capabs_all; > > Does this name come from PAPR? If not, capabilities or caps are > better > for readability than capabs. No capabs is not from PAPR, I just added capabs as short name for capabilities. I will change it to caps as suggested. > > > +static int copypaste_feat; > > Should be a bool? And what does it mean? copy-paste is a host core > capability. copypaste_feat can be bool. But is it used to export user space API if reading all capabilities are successful. > > > + > > +struct vas_capabs vcapabs[VAS_MAX_FEAT_TYPE]; > > + > > +DEFINE_MUTEX(vas_pseries_mutex); > > Can these be made static if they're only used here, and export them > if a > future patch uses them (or add the header declaration now). > > > > + > > static int64_t hcall_return_busy_check(int64_t rc) > > { > > /* Check if we are stalled for some time */ > > @@ -215,3 +222,126 @@ int plpar_vas_query_capabilities(const u64 > > hcall, u8 query_type, > > return -EIO; > > } > > } > > + > > +/* > > + * Get the specific capabilities based on the feature type. > > + * Right now supports GZIP default and GZIP QoS capabilities. > > + */ > > +static int get_vas_capabilities(u8 feat, enum vas_cop_feat_type > > type, > > + struct vas_ct_capabs_be *capab_be) > > +{ > > + struct vas_ct_capabs *capab; > > + struct vas_capabs *vcapab; > > + int rc = 0; > > + > > + vcapab = &vcapabs[type]; > > + memset(vcapab, 0, sizeof(*vcapab)); > > + INIT_LIST_HEAD(&vcapab->list); > > + > > + capab = &vcapab->capab; > > + > > + rc = plpar_vas_query_capabilities(H_QUERY_VAS_CAPABILITIES, > > feat, > > + (u64)virt_to_phys(capab_be)); > > + if (rc) > > + return rc; > > + > > + capab->user_mode = capab_be->user_mode; > > + if (!(capab->user_mode & VAS_COPY_PASTE_USER_MODE)) { > > + pr_err("User space COPY/PASTE is not supported\n"); > > + return -ENOTSUPP; > > + } > > + > > + snprintf(capab->name, VAS_DESCR_LEN + 1, "%.8s", > > + (char *)&capab_be->descriptor); > > + capab->descriptor = be64_to_cpu(capab_be->descriptor); > > + capab->win_type = capab_be->win_type; > > + if (capab->win_type >= VAS_MAX_FEAT_TYPE) { > > + pr_err("Unsupported window type %u\n", capab- > > >win_type); > > + return -EINVAL; > > + } > > + capab->max_lpar_creds = be16_to_cpu(capab_be->max_lpar_creds); > > + capab->max_win_creds = be16_to_cpu(capab_be->max_win_creds); > > + atomic_set(&capab->target_lpar_creds, > > + be16_to_cpu(capab_be->target_lpar_creds)); > > + if (feat == VAS_GZIP_DEF_FEAT) { > > + capab->def_lpar_creds = be16_to_cpu(capab_be- > > >def_lpar_creds); > > + > > + if (capab->max_win_creds < DEF_WIN_CREDS) { > > + pr_err("Window creds(%u) > max allowed window > > creds(%u)\n", > > + DEF_WIN_CREDS, capab->max_win_creds); > > + return -EINVAL; > > + } > > + } > > + > > + copypaste_feat = 1; > > + > > + return 0; > > +} > > + > > +static int __init pseries_vas_init(void) > > +{ > > + struct vas_ct_capabs_be *ct_capabs_be; > > + struct vas_all_capabs_be *capabs_be; > > + int rc; > > + > > + /* > > + * Linux supports user space COPY/PASTE only with Radix > > + */ > > + if (!radix_enabled()) { > > + pr_err("API is supported only with radix page > > tables\n"); > > + return -ENOTSUPP; > > + } > > + > > + capabs_be = kmalloc(sizeof(*capabs_be), GFP_KERNEL); > > + if (!capabs_be) > > + return -ENOMEM; > > + /* > > + * Get VAS overall capabilities by passing 0 to feature type. > > + */ > > + rc = plpar_vas_query_capabilities(H_QUERY_VAS_CAPABILITIES, 0, > > + (u64)virt_to_phys(capabs_be)) > > ; > > + if (rc) > > + goto out; > > + > > + snprintf(capabs_all.name, VAS_DESCR_LEN, "%.7s", > > + (char *)&capabs_be->descriptor); > > + capabs_all.descriptor = be64_to_cpu(capabs_be->descriptor); > > + capabs_all.feat_type = be64_to_cpu(capabs_be->feat_type); > > + > > + ct_capabs_be = kmalloc(sizeof(*ct_capabs_be), GFP_KERNEL); > > + if (!ct_capabs_be) { > > + rc = -ENOMEM; > > + goto out; > > + } > > + /* > > + * QOS capabilities available > > + */ > > + if (capabs_all.feat_type & VAS_GZIP_QOS_FEAT_BIT) { > > + rc = get_vas_capabilities(VAS_GZIP_QOS_FEAT, > > + VAS_GZIP_QOS_FEAT_TYPE, > > ct_capabs_be); > > + > > + if (rc) > > + goto out_ct; > > + } > > + /* > > + * Default capabilities available > > + */ > > + if (capabs_all.feat_type & VAS_GZIP_DEF_FEAT_BIT) { > > + rc = get_vas_capabilities(VAS_GZIP_DEF_FEAT, > > + VAS_GZIP_DEF_FEAT_TYPE, > > ct_capabs_be); > > + if (rc) > > + goto out_ct; > > + } > > Using the same buffer for two hcalls? Do they fill in different parts > of > it? Yes, ct_capabs_be buffer is passed to HCALL to get capabilities for DEF and QOS types. Thanks Haren > > > + > > + if (!copypaste_feat) > > + pr_err("GZIP feature is not supported\n"); > > This is dead code AFAIKS, because errors will always branch to out. > > Thanks, > Nick > > > + > > + pr_info("GZIP feature is available\n"); > > + > > +out_ct: > > + kfree(ct_capabs_be); > > +out: > > + kfree(capabs_be); > > + return rc; > > +} > > +machine_device_initcall(pseries, pseries_vas_init); > > -- > > 2.18.2 > > > > > >