diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/vas-sysfs.c')
| -rw-r--r-- | arch/powerpc/platforms/pseries/vas-sysfs.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/vas-sysfs.c b/arch/powerpc/platforms/pseries/vas-sysfs.c new file mode 100644 index 000000000..f9f682724 --- /dev/null +++ b/arch/powerpc/platforms/pseries/vas-sysfs.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2022-23 IBM Corp. + */ + +#define pr_fmt(fmt) "vas: " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/miscdevice.h> +#include <linux/kobject.h> +#include <linux/slab.h> +#include <linux/mm.h> + +#include "vas.h" + +#ifdef CONFIG_SYSFS +static struct kobject *pseries_vas_kobj; +static struct kobject *gzip_caps_kobj; + +struct vas_caps_entry { + struct kobject kobj; + struct vas_cop_feat_caps *caps; +}; + +#define to_caps_entry(entry) container_of(entry, struct vas_caps_entry, kobj) + +/* + * This function is used to get the notification from the drmgr when + * QoS credits are changed. + */ +static ssize_t update_total_credits_store(struct vas_cop_feat_caps *caps, + const char *buf, size_t count) +{ + int err; + u16 creds; + + err = kstrtou16(buf, 0, &creds); + /* + * The user space interface from the management console + * notifies OS with the new QoS credits and then the + * hypervisor. So OS has to use this new credits value + * and reconfigure VAS windows (close or reopen depends + * on the credits available) instead of depending on VAS + * QoS capabilities from the hypervisor. + */ + if (!err) + err = vas_reconfig_capabilties(caps->win_type, creds); + + if (err) + return -EINVAL; + + pr_info("Set QoS total credits %u\n", creds); + + return count; +} + +#define sysfs_caps_entry_read(_name) \ +static ssize_t _name##_show(struct vas_cop_feat_caps *caps, char *buf) \ +{ \ + return sprintf(buf, "%d\n", atomic_read(&caps->_name)); \ +} + +struct vas_sysfs_entry { + struct attribute attr; + ssize_t (*show)(struct vas_cop_feat_caps *, char *); + ssize_t (*store)(struct vas_cop_feat_caps *, const char *, size_t); +}; + +#define VAS_ATTR_RO(_name) \ + sysfs_caps_entry_read(_name); \ + static struct vas_sysfs_entry _name##_attribute = __ATTR(_name, \ + 0444, _name##_show, NULL); + +/* + * Create sysfs interface: + * /sys/devices/virtual/misc/vas/vas0/gzip/default_capabilities + * This directory contains the following VAS GZIP capabilities + * for the default credit type. + * /sys/devices/virtual/misc/vas/vas0/gzip/default_capabilities/nr_total_credits + * Total number of default credits assigned to the LPAR which + * can be changed with DLPAR operation. + * /sys/devices/virtual/misc/vas/vas0/gzip/default_capabilities/nr_used_credits + * Number of credits used by the user space. One credit will + * be assigned for each window open. + * + * /sys/devices/virtual/misc/vas/vas0/gzip/qos_capabilities + * This directory contains the following VAS GZIP capabilities + * for the Quality of Service (QoS) credit type. + * /sys/devices/virtual/misc/vas/vas0/gzip/qos_capabilities/nr_total_credits + * Total number of QoS credits assigned to the LPAR. The user + * has to define this value using HMC interface. It can be + * changed dynamically by the user. + * /sys/devices/virtual/misc/vas/vas0/gzip/qos_capabilities/nr_used_credits + * Number of credits used by the user space. + * /sys/devices/virtual/misc/vas/vas0/gzip/qos_capabilities/update_total_credits + * Update total QoS credits dynamically + */ + +VAS_ATTR_RO(nr_total_credits); +VAS_ATTR_RO(nr_used_credits); + +static struct vas_sysfs_entry update_total_credits_attribute = + __ATTR(update_total_credits, 0200, NULL, update_total_credits_store); + +static struct attribute *vas_def_capab_attrs[] = { + &nr_total_credits_attribute.attr, + &nr_used_credits_attribute.attr, + NULL, +}; +ATTRIBUTE_GROUPS(vas_def_capab); + +static struct attribute *vas_qos_capab_attrs[] = { + &nr_total_credits_attribute.attr, + &nr_used_credits_attribute.attr, + &update_total_credits_attribute.attr, + NULL, +}; +ATTRIBUTE_GROUPS(vas_qos_capab); + +static ssize_t vas_type_show(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + struct vas_caps_entry *centry; + struct vas_cop_feat_caps *caps; + struct vas_sysfs_entry *entry; + + centry = to_caps_entry(kobj); + caps = centry->caps; + entry = container_of(attr, struct vas_sysfs_entry, attr); + + if (!entry->show) + return -EIO; + + return entry->show(caps, buf); +} + +static ssize_t vas_type_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + struct vas_caps_entry *centry; + struct vas_cop_feat_caps *caps; + struct vas_sysfs_entry *entry; + + centry = to_caps_entry(kobj); + caps = centry->caps; + entry = container_of(attr, struct vas_sysfs_entry, attr); + if (!entry->store) + return -EIO; + + return entry->store(caps, buf, count); +} + +static void vas_type_release(struct kobject *kobj) +{ + struct vas_caps_entry *centry = to_caps_entry(kobj); + kfree(centry); +} + +static const struct sysfs_ops vas_sysfs_ops = { + .show = vas_type_show, + .store = vas_type_store, +}; + +static struct kobj_type vas_def_attr_type = { + .release = vas_type_release, + .sysfs_ops = &vas_sysfs_ops, + .default_groups = vas_def_capab_groups, +}; + +static struct kobj_type vas_qos_attr_type = { + .release = vas_type_release, + .sysfs_ops = &vas_sysfs_ops, + .default_groups = vas_qos_capab_groups, +}; + +static char *vas_caps_kobj_name(struct vas_caps_entry *centry, + struct kobject **kobj) +{ + struct vas_cop_feat_caps *caps = centry->caps; + + if (caps->descriptor == VAS_GZIP_QOS_CAPABILITIES) { + kobject_init(¢ry->kobj, &vas_qos_attr_type); + *kobj = gzip_caps_kobj; + return "qos_capabilities"; + } else if (caps->descriptor == VAS_GZIP_DEFAULT_CAPABILITIES) { + kobject_init(¢ry->kobj, &vas_def_attr_type); + *kobj = gzip_caps_kobj; + return "default_capabilities"; + } else + return "Unknown"; +} + +/* + * Add feature specific capability dir entry. + * Ex: VDefGzip or VQosGzip + */ +int sysfs_add_vas_caps(struct vas_cop_feat_caps *caps) +{ + struct vas_caps_entry *centry; + struct kobject *kobj = NULL; + int ret = 0; + char *name; + + centry = kzalloc(sizeof(*centry), GFP_KERNEL); + if (!centry) + return -ENOMEM; + + centry->caps = caps; + name = vas_caps_kobj_name(centry, &kobj); + + if (kobj) { + ret = kobject_add(¢ry->kobj, kobj, "%s", name); + + if (ret) { + pr_err("VAS: sysfs kobject add / event failed %d\n", + ret); + kobject_put(¢ry->kobj); + } + } + + return ret; +} + +static struct miscdevice vas_miscdev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "vas", +}; + +/* + * Add VAS and VasCaps (overall capabilities) dir entries. + */ +int __init sysfs_pseries_vas_init(struct vas_all_caps *vas_caps) +{ + int ret; + + ret = misc_register(&vas_miscdev); + if (ret < 0) { + pr_err("%s: register vas misc device failed\n", __func__); + return ret; + } + + /* + * The hypervisor does not expose multiple VAS instances, but can + * see multiple VAS instances on PowerNV. So create 'vas0' directory + * on pseries. + */ + pseries_vas_kobj = kobject_create_and_add("vas0", + &vas_miscdev.this_device->kobj); + if (!pseries_vas_kobj) { + misc_deregister(&vas_miscdev); + 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); + misc_deregister(&vas_miscdev); + 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 |