Excerpts from Haren Myneni's message of June 13, 2021 9:01 pm: > > The hypervisor provides VAS capabilities for GZIP default and QoS > features. These capabilities gives information for the specific > features such as total number of credits available in LPAR, > maximum credits allowed per window, maximum credits allowed in > LPAR, whether usermode copy/paste is supported, and etc. > > This patch adds the following: > - Retrieve all features that are provided by hypervisor using > H_QUERY_VAS_CAPABILITIES hcall with 0 as feature type. > - Retrieve capabilities for the specific feature using the same > hcall and the feature type (1 for QoS and 2 for default type). > > Signed-off-by: Haren Myneni <haren@xxxxxxxxxxxxx> > --- > arch/powerpc/platforms/pseries/vas.c | 124 +++++++++++++++++++++++++++ > 1 file changed, 124 insertions(+) > > diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c > index fec280979d50..98109a13f1c2 100644 > --- a/arch/powerpc/platforms/pseries/vas.c > +++ b/arch/powerpc/platforms/pseries/vas.c > @@ -10,6 +10,7 @@ > #include <linux/export.h> > #include <linux/types.h> > #include <linux/delay.h> > +#include <asm/machdep.h> > #include <asm/hvcall.h> > #include <asm/plpar_wrappers.h> > #include <asm/vas.h> > @@ -20,6 +21,13 @@ > /* phyp allows one credit per window right now */ > #define DEF_WIN_CREDS 1 > > +static struct vas_all_caps caps_all; > +static bool copypaste_feat; > + > +static struct vas_caps vascaps[VAS_MAX_FEAT_TYPE]; If these will all be read by later patches I think that's okay, however: > + > +static DEFINE_MUTEX(vas_pseries_mutex); This is not used at all. It should be added in the patch that uses it. Thanks, Nick > + > static long hcall_return_busy_check(long rc) > { > /* Check if we are stalled for some time */ > @@ -179,3 +187,119 @@ int h_query_vas_capabilities(const u64 hcall, u8 query_type, u64 result) > 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 hv_vas_ct_caps *hv_caps) > +{ > + struct vas_ct_caps *caps; > + struct vas_caps *vcaps; > + int rc = 0; > + > + vcaps = &vascaps[type]; > + memset(vcaps, 0, sizeof(*vcaps)); > + INIT_LIST_HEAD(&vcaps->list); > + > + caps = &vcaps->caps; > + > + rc = h_query_vas_capabilities(H_QUERY_VAS_CAPABILITIES, feat, > + (u64)virt_to_phys(hv_caps)); > + if (rc) > + return rc; > + > + caps->user_mode = hv_caps->user_mode; > + if (!(caps->user_mode & VAS_COPY_PASTE_USER_MODE)) { > + pr_err("User space COPY/PASTE is not supported\n"); > + return -ENOTSUPP; > + } > + > + caps->descriptor = be64_to_cpu(hv_caps->descriptor); > + caps->win_type = hv_caps->win_type; > + if (caps->win_type >= VAS_MAX_FEAT_TYPE) { > + pr_err("Unsupported window type %u\n", caps->win_type); > + return -EINVAL; > + } > + caps->max_lpar_creds = be16_to_cpu(hv_caps->max_lpar_creds); > + caps->max_win_creds = be16_to_cpu(hv_caps->max_win_creds); > + atomic_set(&caps->target_lpar_creds, > + be16_to_cpu(hv_caps->target_lpar_creds)); > + if (feat == VAS_GZIP_DEF_FEAT) { > + caps->def_lpar_creds = be16_to_cpu(hv_caps->def_lpar_creds); > + > + if (caps->max_win_creds < DEF_WIN_CREDS) { > + pr_err("Window creds(%u) > max allowed window creds(%u)\n", > + DEF_WIN_CREDS, caps->max_win_creds); > + return -EINVAL; > + } > + } > + > + copypaste_feat = true; > + > + return 0; > +} > + > +static int __init pseries_vas_init(void) > +{ > + struct hv_vas_ct_caps *hv_ct_caps; > + struct hv_vas_all_caps *hv_caps; > + 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; > + } > + > + hv_caps = kmalloc(sizeof(*hv_caps), GFP_KERNEL); > + if (!hv_caps) > + return -ENOMEM; > + /* > + * Get VAS overall capabilities by passing 0 to feature type. > + */ > + rc = h_query_vas_capabilities(H_QUERY_VAS_CAPABILITIES, 0, > + (u64)virt_to_phys(hv_caps)); > + if (rc) > + goto out; > + > + caps_all.descriptor = be64_to_cpu(hv_caps->descriptor); > + caps_all.feat_type = be64_to_cpu(hv_caps->feat_type); > + > + hv_ct_caps = kmalloc(sizeof(*hv_ct_caps), GFP_KERNEL); > + if (!hv_ct_caps) { > + rc = -ENOMEM; > + goto out; > + } > + /* > + * QOS capabilities available > + */ > + if (caps_all.feat_type & VAS_GZIP_QOS_FEAT_BIT) { > + rc = get_vas_capabilities(VAS_GZIP_QOS_FEAT, > + VAS_GZIP_QOS_FEAT_TYPE, hv_ct_caps); > + > + if (rc) > + goto out_ct; > + } > + /* > + * Default capabilities available > + */ > + if (caps_all.feat_type & VAS_GZIP_DEF_FEAT_BIT) { > + rc = get_vas_capabilities(VAS_GZIP_DEF_FEAT, > + VAS_GZIP_DEF_FEAT_TYPE, hv_ct_caps); > + if (rc) > + goto out_ct; > + } > + > + pr_info("GZIP feature is available\n"); > + > +out_ct: > + kfree(hv_ct_caps); > +out: > + kfree(hv_caps); > + return rc; > +} > +machine_device_initcall(pseries, pseries_vas_init); > -- > 2.18.2 > > >