--- /dev/null
+// 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)
+
+#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/vas/vas0/gzip/default_capabilities
+ * This directory contains the following VAS GZIP capabilities
+ * for the defaule credit type.
+ * /sys/devices/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/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/vas/vas0/gzip/qos_capabilities
+ * This directory contains the following VAS GZIP capabilities
+ * for the Quality of Service (QoS) credit type.
+ * /sys/devices/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/vas/vas0/gzip/qos_capabilities/nr_used_credits
+ * Number of credits used by the user space.
+ */
+
+VAS_ATTR_RO(nr_total_credits);
+VAS_ATTR_RO(nr_used_credits);
+
+static struct attribute *vas_capab_attrs[] = {
+ &nr_total_credits_attribute.attr,
+ &nr_used_credits_attribute.attr,
+ NULL,
+};
+
+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_attr_type = {
+ .release = vas_type_release,
+ .sysfs_ops = &vas_sysfs_ops,
+ .default_attrs = vas_capab_attrs,
+};
+
+static char *vas_caps_kobj_name(struct vas_cop_feat_caps *caps,
+ struct kobject **kobj)
+{
+ if (caps->descriptor == VAS_GZIP_QOS_CAPABILITIES) {
+ *kobj = gzip_caps_kobj;
+ return "qos_capabilities";
+ } else if (caps->descriptor == VAS_GZIP_DEFAULT_CAPABILITIES) {
+ *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;
+
+ kobject_init(¢ry->kobj, &vas_attr_type);
+ centry->caps = caps;
+ name = vas_caps_kobj_name(caps, &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) {
+ 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
projects / users / hch / xfs.git / commitdiff