1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Interface for Dynamic Logical Partitioning of I/O Slots on
4  * RPA-compliant PPC64 platform.
5  *
6  * John Rose <johnrose@austin.ibm.com>
7  * October 2003
8  *
9  * Copyright (C) 2003 IBM.
10  */
11 #include <linux/kobject.h>
12 #include <linux/string.h>
13 #include <linux/pci.h>
14 #include <linux/pci_hotplug.h>
15 #include "rpaphp.h"
16 #include "rpadlpar.h"
17 #include "../pci.h"
18 
19 #define DLPAR_KOBJ_NAME       "control"
20 
21 /* Those two have no quotes because they are passed to __ATTR() which
22  * stringifies the argument (yuck !)
23  */
24 #define ADD_SLOT_ATTR_NAME    add_slot
25 #define REMOVE_SLOT_ATTR_NAME remove_slot
26 
add_slot_store(struct kobject * kobj,struct kobj_attribute * attr,const char * buf,size_t nbytes)27 static ssize_t add_slot_store(struct kobject *kobj, struct kobj_attribute *attr,
28 			      const char *buf, size_t nbytes)
29 {
30 	char drc_name[MAX_DRC_NAME_LEN];
31 	char *end;
32 	int rc;
33 
34 	if (nbytes >= MAX_DRC_NAME_LEN)
35 		return 0;
36 
37 	strscpy(drc_name, buf, nbytes + 1);
38 
39 	end = strchr(drc_name, '\n');
40 	if (end)
41 		*end = '\0';
42 
43 	rc = dlpar_add_slot(drc_name);
44 	if (rc)
45 		return rc;
46 
47 	return nbytes;
48 }
49 
add_slot_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)50 static ssize_t add_slot_show(struct kobject *kobj,
51 			     struct kobj_attribute *attr, char *buf)
52 {
53 	return sysfs_emit(buf, "0\n");
54 }
55 
remove_slot_store(struct kobject * kobj,struct kobj_attribute * attr,const char * buf,size_t nbytes)56 static ssize_t remove_slot_store(struct kobject *kobj,
57 				 struct kobj_attribute *attr,
58 				 const char *buf, size_t nbytes)
59 {
60 	char drc_name[MAX_DRC_NAME_LEN];
61 	int rc;
62 	char *end;
63 
64 	if (nbytes >= MAX_DRC_NAME_LEN)
65 		return 0;
66 
67 	strscpy(drc_name, buf, nbytes + 1);
68 
69 	end = strchr(drc_name, '\n');
70 	if (end)
71 		*end = '\0';
72 
73 	rc = dlpar_remove_slot(drc_name);
74 	if (rc)
75 		return rc;
76 
77 	return nbytes;
78 }
79 
remove_slot_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)80 static ssize_t remove_slot_show(struct kobject *kobj,
81 				struct kobj_attribute *attr, char *buf)
82 {
83 	return sysfs_emit(buf, "0\n");
84 }
85 
86 static struct kobj_attribute add_slot_attr =
87 	__ATTR(ADD_SLOT_ATTR_NAME, 0644, add_slot_show, add_slot_store);
88 
89 static struct kobj_attribute remove_slot_attr =
90 	__ATTR(REMOVE_SLOT_ATTR_NAME, 0644, remove_slot_show, remove_slot_store);
91 
92 static struct attribute *default_attrs[] = {
93 	&add_slot_attr.attr,
94 	&remove_slot_attr.attr,
95 	NULL,
96 };
97 
98 static const struct attribute_group dlpar_attr_group = {
99 	.attrs = default_attrs,
100 };
101 
102 static struct kobject *dlpar_kobj;
103 
dlpar_sysfs_init(void)104 int dlpar_sysfs_init(void)
105 {
106 	int error;
107 
108 	dlpar_kobj = kobject_create_and_add(DLPAR_KOBJ_NAME,
109 					    &pci_slots_kset->kobj);
110 	if (!dlpar_kobj)
111 		return -EINVAL;
112 
113 	error = sysfs_create_group(dlpar_kobj, &dlpar_attr_group);
114 	if (error)
115 		kobject_put(dlpar_kobj);
116 	return error;
117 }
118 
dlpar_sysfs_exit(void)119 void dlpar_sysfs_exit(void)
120 {
121 	sysfs_remove_group(dlpar_kobj, &dlpar_attr_group);
122 	kobject_put(dlpar_kobj);
123 }
124