blob: f9f682724e776356fee595da562c1dfac75fa847 [file] [log] [blame]
// 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(&centry->kobj, &vas_qos_attr_type);
*kobj = gzip_caps_kobj;
return "qos_capabilities";
} else if (caps->descriptor == VAS_GZIP_DEFAULT_CAPABILITIES) {
kobject_init(&centry->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(&centry->kobj, kobj, "%s", name);
if (ret) {
pr_err("VAS: sysfs kobject add / event failed %d\n",
ret);
kobject_put(&centry->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