text: // SPDX-License-Identifier: GPL-2.0+
  /*
   * Interface for Dynamic Logical Partitioning of I/O Slots on
   * RPA-compliant PPC64 platform.
   *
   * John Rose <johnrose@austin.ibm.com>
   * October 2003
   *
   * Copyright (C) 2003 IBM.
   */
  #include <linux/kobject.h>
  #include <linux/string.h>
  #include <linux/pci.h>
  #include <linux/pci_hotplug.h>
  #include "rpaphp.h"
  #include "rpadlpar.h"
  #include "../pci.h"
  
  #define DLPAR_KOBJ_NAME       "control"
  
  /* Those two have no quotes because they are passed to __ATTR() which
   * stringifies the argument (yuck !)
   */
  #define ADD_SLOT_ATTR_NAME    add_slot
  #define REMOVE_SLOT_ATTR_NAME remove_slot
  
  static ssize_t add_slot_store(struct kobject *kobj, struct kobj_attribute *attr,
  			      const char *buf, size_t nbytes)
  {
  	char drc_name[MAX_DRC_NAME_LEN];
  	char *end;
  	int rc;
  
  	if (nbytes >= MAX_DRC_NAME_LEN)
  		return 0;
  
  	memcpy(drc_name, buf, nbytes);
  
  	end = strchr(drc_name, '\n');
  	if (!end)
  		end = &drc_name[nbytes];
  	*end = '\0';
  
  	rc = dlpar_add_slot(drc_name);
  	if (rc)
  		return rc;
  
  	return nbytes;
  }
  
  static ssize_t add_slot_show(struct kobject *kobj,
  			     struct kobj_attribute *attr, char *buf)
  {
  	return sprintf(buf, "0\n");
  }
  
  static ssize_t remove_slot_store(struct kobject *kobj,
  				 struct kobj_attribute *attr,
  				 const char *buf, size_t nbytes)
  {
  	char drc_name[MAX_DRC_NAME_LEN];
  	int rc;
  	char *end;
  
  	if (nbytes >= MAX_DRC_NAME_LEN)
  		return 0;
  
  	memcpy(drc_name, buf, nbytes);
  
  	end = strchr(drc_name, '\n');
  	if (!end)
  		end = &drc_name[nbytes];
  	*end = '\0';
  
  	rc = dlpar_remove_slot(drc_name);
  	if (rc)
  		return rc;
  
  	return nbytes;
  }
  
  static ssize_t remove_slot_show(struct kobject *kobj,
  				struct kobj_attribute *attr, char *buf)
  {
  	return sprintf(buf, "0\n");
  }
  
  static struct kobj_attribute add_slot_attr =
  	__ATTR(ADD_SLOT_ATTR_NAME, 0644, add_slot_show, add_slot_store);
  
  static struct kobj_attribute remove_slot_attr =
  	__ATTR(REMOVE_SLOT_ATTR_NAME, 0644, remove_slot_show, remove_slot_store);
  
  static struct attribute *default_attrs[] = {
  	&add_slot_attr.attr,
  	&remove_slot_attr.attr,
  	NULL,
  };
  
  static const struct attribute_group dlpar_attr_group = {
  	.attrs = default_attrs,
  };
  
  static struct kobject *dlpar_kobj;
  
  int dlpar_sysfs_init(void)
  {
  	int error;
  
  	dlpar_kobj = kobject_create_and_add(DLPAR_KOBJ_NAME,
  					    &pci_slots_kset->kobj);
  	if (!dlpar_kobj)
  		return -EINVAL;
  
  	error = sysfs_create_group(dlpar_kobj, &dlpar_attr_group);
  	if (error)
  		kobject_put(dlpar_kobj);
  	return error;
  }
  
  void dlpar_sysfs_exit(void)
  {
  	sysfs_remove_group(dlpar_kobj, &dlpar_attr_group);
  	kobject_put(dlpar_kobj);
  }
  