adf_cfg.c

// SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
/* Copyright(c) 2014 - 2020 Intel Corporation */
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/seq_file.h>
#include "adf_accel_devices.h"
#include "adf_cfg.h"
#include "adf_common_drv.h"

static DEFINE_MUTEX(qat_cfg_read_lock);

static void *qat_dev_cfg_start(struct seq_file *sfile, loff_t *pos)
{
	struct adf_cfg_device_data *dev_cfg = sfile->private;

	mutex_lock(&qat_cfg_read_lock);
	return seq_list_start(&dev_cfg->sec_list, *pos);
}

static int qat_dev_cfg_show(struct seq_file *sfile, void *v)
{
	struct list_head *list;
	struct adf_cfg_section *sec =
				list_entry(v, struct adf_cfg_section, list);

	seq_printf(sfile, "[%s]\n", sec->name);
	list_for_each(list, &sec->param_head) {
		struct adf_cfg_key_val *ptr =
			list_entry(list, struct adf_cfg_key_val, list);
		seq_printf(sfile, "%s = %s\n", ptr->key, ptr->val);
	}
	return 0;
}

static void *qat_dev_cfg_next(struct seq_file *sfile, void *v, loff_t *pos)
{
	struct adf_cfg_device_data *dev_cfg = sfile->private;

	return seq_list_next(v, &dev_cfg->sec_list, pos);
}

static void qat_dev_cfg_stop(struct seq_file *sfile, void *v)
{
	mutex_unlock(&qat_cfg_read_lock);
}

static const struct seq_operations qat_dev_cfg_sops = {
	.start = qat_dev_cfg_start,
	.next = qat_dev_cfg_next,
	.stop = qat_dev_cfg_stop,
	.show = qat_dev_cfg_show
};

DEFINE_SEQ_ATTRIBUTE(qat_dev_cfg);

/**
 * adf_cfg_dev_add() - Create an acceleration device configuration table.
 * @accel_dev:  Pointer to acceleration device.
 *
 * Function creates a configuration table for the given acceleration device.
 * The table stores device specific config values.
 * To be used by QAT device specific drivers.
 *
 * Return: 0 on success, error code otherwise.
 */
int adf_cfg_dev_add(struct adf_accel_dev *accel_dev)
{
	struct adf_cfg_device_data *dev_cfg_data;

	dev_cfg_data = kzalloc(sizeof(*dev_cfg_data), GFP_KERNEL);
	if (!dev_cfg_data)
		return -ENOMEM;
	INIT_LIST_HEAD(&dev_cfg_data->sec_list);
	init_rwsem(&dev_cfg_data->lock);
	accel_dev->cfg = dev_cfg_data;
	return 0;
}
EXPORT_SYMBOL_GPL(adf_cfg_dev_add);

void adf_cfg_dev_dbgfs_add(struct adf_accel_dev *accel_dev)
{
	struct adf_cfg_device_data *dev_cfg_data = accel_dev->cfg;

	dev_cfg_data->debug = debugfs_create_file("dev_cfg", 0400,
						  accel_dev->debugfs_dir,
						  dev_cfg_data,
						  &qat_dev_cfg_fops);
}

void adf_cfg_dev_dbgfs_rm(struct adf_accel_dev *accel_dev)
{
	struct adf_cfg_device_data *dev_cfg_data = accel_dev->cfg;

	if (!dev_cfg_data)
		return;

	debugfs_remove(dev_cfg_data->debug);
	dev_cfg_data->debug = NULL;
}

static void adf_cfg_section_del_all(struct list_head *head);
static void adf_cfg_section_del_all_except(struct list_head *head,
					   const char *section_name);

void adf_cfg_del_all(struct adf_accel_dev *accel_dev)
{
	struct adf_cfg_device_data *dev_cfg_data = accel_dev->cfg;

	down_write(&dev_cfg_data->lock);
	adf_cfg_section_del_all(&dev_cfg_data->sec_list);
	up_write(&dev_cfg_data->lock);
	clear_bit(ADF_STATUS_CONFIGURED, &accel_dev->status);
}

void adf_cfg_del_all_except(struct adf_accel_dev *accel_dev,
			    const char *section_name)
{
	struct adf_cfg_device_data *dev_cfg_data = accel_dev->cfg;

	down_write(&dev_cfg_data->lock);
	adf_cfg_section_del_all_except(&dev_cfg_data->sec_list, section_name);
	up_write(&dev_cfg_data->lock);
	clear_bit(ADF_STATUS_CONFIGURED, &accel_dev->status);
}

/**
 * adf_cfg_dev_remove() - Clears acceleration device configuration table.
 * @accel_dev:  Pointer to acceleration device.
 *
 * Function removes configuration table from the given acceleration device
 * and frees all allocated memory.
 * To be used by QAT device specific drivers.
 *
 * Return: void
 */
void adf_cfg_dev_remove(struct adf_accel_dev *accel_dev)
{
	struct adf_cfg_device_data *dev_cfg_data = accel_dev->cfg;

	if (!dev_cfg_data)
		return;

	down_write(&dev_cfg_data->lock);
	adf_cfg_section_del_all(&dev_cfg_data->sec_list);
	up_write(&dev_cfg_data->lock);
	kfree(dev_cfg_data);
	accel_dev->cfg = NULL;
}
EXPORT_SYMBOL_GPL(adf_cfg_dev_remove);

static void adf_cfg_keyval_add(struct adf_cfg_key_val *new,
			       struct adf_cfg_section *sec)
{
	list_add_tail(&new->list, &sec->param_head);
}

static void adf_cfg_keyval_remove(const char *key, struct adf_cfg_section *sec)
{
	struct list_head *head = &sec->param_head;
	struct list_head *list_ptr, *tmp;

	list_for_each_prev_safe(list_ptr, tmp, head) {
		struct adf_cfg_key_val *ptr =
			list_entry(list_ptr, struct adf_cfg_key_val, list);

		if (strncmp(ptr->key, key, sizeof(ptr->key)))
			continue;

		list_del(list_ptr);
		kfree(ptr);
		break;
	}
}

static void adf_cfg_keyval_del_all(struct list_head *head)
{
	struct list_head *list_ptr, *tmp;

	list_for_each_prev_safe(list_ptr, tmp, head) {
		struct adf_cfg_key_val *ptr =
			list_entry(list_ptr, struct adf_cfg_key_val, list);
		list_del(list_ptr);
		kfree(ptr);
	}
}

static void adf_cfg_section_del_all(struct list_head *head)
{
	struct adf_cfg_section *ptr;
	struct list_head *list, *tmp;

	list_for_each_prev_safe(list, tmp, head) {
		ptr = list_entry(list, struct adf_cfg_section, list);
		adf_cfg_keyval_del_all(&ptr->param_head);
		list_del(list);
		kfree(ptr);
	}
}

static void adf_cfg_section_del_all_except(struct list_head *head,
					   const char *section_name)
{
	struct list_head *list, *tmp;
	struct adf_cfg_section *ptr;

	list_for_each_prev_safe(list, tmp, head) {
		ptr = list_entry(list, struct adf_cfg_section, list);
		if (!strcmp(ptr->name, section_name))
			continue;
		adf_cfg_keyval_del_all(&ptr->param_head);
		list_del(list);
		kfree(ptr);
	}
}

static struct adf_cfg_key_val *adf_cfg_key_value_find(struct adf_cfg_section *s,
						      const char *key)
{
	struct list_head *list;

	list_for_each(list, &s->param_head) {
		struct adf_cfg_key_val *ptr =
			list_entry(list, struct adf_cfg_key_val, list);
		if (!strcmp(ptr->key, key))
			return ptr;
	}
	return NULL;
}

static struct adf_cfg_section *adf_cfg_sec_find(struct adf_accel_dev *accel_dev,
						const char *sec_name)
{
	struct adf_cfg_device_data *cfg = accel_dev->cfg;
	struct list_head *list;

	list_for_each(list, &cfg->sec_list) {
		struct adf_cfg_section *ptr =
			list_entry(list, struct adf_cfg_section, list);
		if (!strcmp(ptr->name, sec_name))
			return ptr;
	}
	return NULL;
}

static int adf_cfg_key_val_get(struct adf_accel_dev *accel_dev,
			       const char *sec_name,
			       const char *key_name,
			       char *val)
{
	struct adf_cfg_section *sec = adf_cfg_sec_find(accel_dev, sec_name);
	struct adf_cfg_key_val *keyval = NULL;

	if (sec)
		keyval = adf_cfg_key_value_find(sec, key_name);
	if (keyval) {
		memcpy(val, keyval->val, ADF_CFG_MAX_VAL_LEN_IN_BYTES);
		return 0;
	}
	return -ENODATA;
}

/**
 * adf_cfg_add_key_value_param() - Add key-value config entry to config table.
 * @accel_dev:  Pointer to acceleration device.
 * @section_name: Name of the section where the param will be added
 * @key: The key string
 * @val: Value pain for the given @key
 * @type: Type - string, int or address
 *
 * Function adds configuration key - value entry in the appropriate section
 * in the given acceleration device. If the key exists already, the value
 * is updated.
 * To be used by QAT device specific drivers.
 *
 * Return: 0 on success, error code otherwise.
 */
int adf_cfg_add_key_value_param(struct adf_accel_dev *accel_dev,
				const char *section_name,
				const char *key, const void *val,
				enum adf_cfg_val_type type)
{
	struct adf_cfg_device_data *cfg = accel_dev->cfg;
	struct adf_cfg_key_val *key_val;
	struct adf_cfg_section *section = adf_cfg_sec_find(accel_dev,
							   section_name);
	char temp_val[ADF_CFG_MAX_VAL_LEN_IN_BYTES];

	if (!section)
		return -EFAULT;

	key_val = kzalloc(sizeof(*key_val), GFP_KERNEL);
	if (!key_val)
		return -ENOMEM;

	INIT_LIST_HEAD(&key_val->list);
	strscpy(key_val->key, key, sizeof(key_val->key));

	if (type == ADF_DEC) {
		snprintf(key_val->val, ADF_CFG_MAX_VAL_LEN_IN_BYTES,
			 "%ld", (*((long *)val)));
	} else if (type == ADF_STR) {
		strscpy(key_val->val, (char *)val, sizeof(key_val->val));
	} else if (type == ADF_HEX) {
		snprintf(key_val->val, ADF_CFG_MAX_VAL_LEN_IN_BYTES,
			 "0x%lx", (unsigned long)val);
	} else {
		dev_err(&GET_DEV(accel_dev), "Unknown type given.\n");
		kfree(key_val);
		return -EINVAL;
	}
	key_val->type = type;

	/* Add the key-value pair as below policy:
	 * 1. if the key doesn't exist, add it;
	 * 2. if the key already exists with a different value then update it
	 *    to the new value (the key is deleted and the newly created
	 *    key_val containing the new value is added to the database);
	 * 3. if the key exists with the same value, then return without doing
	 *    anything (the newly created key_val is freed).
	 */
	down_write(&cfg->lock);
	if (!adf_cfg_key_val_get(accel_dev, section_name, key, temp_val)) {
		if (strncmp(temp_val, key_val->val, sizeof(temp_val))) {
			adf_cfg_keyval_remove(key, section);
		} else {
			kfree(key_val);
			goto out;
		}
	}

	adf_cfg_keyval_add(key_val, section);

out:
	up_write(&cfg->lock);
	return 0;
}
EXPORT_SYMBOL_GPL(adf_cfg_add_key_value_param);

/**
 * adf_cfg_section_add() - Add config section entry to config table.
 * @accel_dev:  Pointer to acceleration device.
 * @name: Name of the section
 *
 * Function adds configuration section where key - value entries
 * will be stored.
 * To be used by QAT device specific drivers.
 *
 * Return: 0 on success, error code otherwise.
 */
int adf_cfg_section_add(struct adf_accel_dev *accel_dev, const char *name)
{
	struct adf_cfg_device_data *cfg = accel_dev->cfg;
	struct adf_cfg_section *sec = adf_cfg_sec_find(accel_dev, name);

	if (sec)
		return 0;

	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
	if (!sec)
		return -ENOMEM;

	strscpy(sec->name, name, sizeof(sec->name));
	INIT_LIST_HEAD(&sec->param_head);
	down_write(&cfg->lock);
	list_add_tail(&sec->list, &cfg->sec_list);
	up_write(&cfg->lock);
	return 0;
}
EXPORT_SYMBOL_GPL(adf_cfg_section_add);

int adf_cfg_get_param_value(struct adf_accel_dev *accel_dev,
			    const char *section, const char *name,
			    char *value)
{
	struct adf_cfg_device_data *cfg = accel_dev->cfg;
	int ret;

	down_read(&cfg->lock);
	ret = adf_cfg_key_val_get(accel_dev, section, name, value);
	up_read(&cfg->lock);
	return ret;
}
EXPORT_SYMBOL_GPL(adf_cfg_get_param_value);