1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2012
4 *
5 * Author(s):
6 * Jan Glauber <jang@linux.vnet.ibm.com>
7 */
8
9 #define KMSG_COMPONENT "zpci"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12 #include <linux/kernel.h>
13 #include <linux/stat.h>
14 #include <linux/pci.h>
15
16 #include "../../../drivers/pci/pci.h"
17
18 #include <asm/sclp.h>
19
20 #define zpci_attr(name, fmt, member) \
21 static ssize_t name##_show(struct device *dev, \
22 struct device_attribute *attr, char *buf) \
23 { \
24 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev)); \
25 \
26 return sprintf(buf, fmt, zdev->member); \
27 } \
28 static DEVICE_ATTR_RO(name)
29
30 zpci_attr(function_id, "0x%08x\n", fid);
31 zpci_attr(function_handle, "0x%08x\n", fh);
32 zpci_attr(pchid, "0x%04x\n", pchid);
33 zpci_attr(pfgid, "0x%02x\n", pfgid);
34 zpci_attr(vfn, "0x%04x\n", vfn);
35 zpci_attr(pft, "0x%02x\n", pft);
36 zpci_attr(port, "%d\n", port);
37 zpci_attr(uid, "0x%x\n", uid);
38 zpci_attr(segment0, "0x%02x\n", pfip[0]);
39 zpci_attr(segment1, "0x%02x\n", pfip[1]);
40 zpci_attr(segment2, "0x%02x\n", pfip[2]);
41 zpci_attr(segment3, "0x%02x\n", pfip[3]);
42
mio_enabled_show(struct device * dev,struct device_attribute * attr,char * buf)43 static ssize_t mio_enabled_show(struct device *dev,
44 struct device_attribute *attr, char *buf)
45 {
46 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
47
48 return sprintf(buf, zpci_use_mio(zdev) ? "1\n" : "0\n");
49 }
50 static DEVICE_ATTR_RO(mio_enabled);
51
recover_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)52 static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
53 const char *buf, size_t count)
54 {
55 struct kernfs_node *kn;
56 struct pci_dev *pdev = to_pci_dev(dev);
57 struct zpci_dev *zdev = to_zpci(pdev);
58 int ret = 0;
59
60 /* Can't use device_remove_self() here as that would lead us to lock
61 * the pci_rescan_remove_lock while holding the device' kernfs lock.
62 * This would create a possible deadlock with disable_slot() which is
63 * not directly protected by the device' kernfs lock but takes it
64 * during the device removal which happens under
65 * pci_rescan_remove_lock.
66 *
67 * This is analogous to sdev_store_delete() in
68 * drivers/scsi/scsi_sysfs.c
69 */
70 kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
71 WARN_ON_ONCE(!kn);
72 /* device_remove_file() serializes concurrent calls ignoring all but
73 * the first
74 */
75 device_remove_file(dev, attr);
76
77 /* A concurrent call to recover_store() may slip between
78 * sysfs_break_active_protection() and the sysfs file removal.
79 * Once it unblocks from pci_lock_rescan_remove() the original pdev
80 * will already be removed.
81 */
82 pci_lock_rescan_remove();
83 if (pci_dev_is_added(pdev)) {
84 pci_stop_and_remove_bus_device(pdev);
85 if (zdev->dma_table) {
86 ret = zpci_dma_exit_device(zdev);
87 if (ret)
88 goto out;
89 }
90
91 if (zdev_enabled(zdev)) {
92 ret = zpci_disable_device(zdev);
93 /*
94 * Due to a z/VM vs LPAR inconsistency in the error
95 * state the FH may indicate an enabled device but
96 * disable says the device is already disabled don't
97 * treat it as an error here.
98 */
99 if (ret == -EINVAL)
100 ret = 0;
101 if (ret)
102 goto out;
103 }
104
105 ret = zpci_enable_device(zdev);
106 if (ret)
107 goto out;
108 ret = zpci_dma_init_device(zdev);
109 if (ret) {
110 zpci_disable_device(zdev);
111 goto out;
112 }
113 pci_rescan_bus(zdev->zbus->bus);
114 }
115 out:
116 pci_unlock_rescan_remove();
117 if (kn)
118 sysfs_unbreak_active_protection(kn);
119 return ret ? ret : count;
120 }
121 static DEVICE_ATTR_WO(recover);
122
util_string_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)123 static ssize_t util_string_read(struct file *filp, struct kobject *kobj,
124 struct bin_attribute *attr, char *buf,
125 loff_t off, size_t count)
126 {
127 struct device *dev = kobj_to_dev(kobj);
128 struct pci_dev *pdev = to_pci_dev(dev);
129 struct zpci_dev *zdev = to_zpci(pdev);
130
131 return memory_read_from_buffer(buf, count, &off, zdev->util_str,
132 sizeof(zdev->util_str));
133 }
134 static BIN_ATTR_RO(util_string, CLP_UTIL_STR_LEN);
135
report_error_write(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)136 static ssize_t report_error_write(struct file *filp, struct kobject *kobj,
137 struct bin_attribute *attr, char *buf,
138 loff_t off, size_t count)
139 {
140 struct zpci_report_error_header *report = (void *) buf;
141 struct device *dev = kobj_to_dev(kobj);
142 struct pci_dev *pdev = to_pci_dev(dev);
143 struct zpci_dev *zdev = to_zpci(pdev);
144 int ret;
145
146 if (off || (count < sizeof(*report)))
147 return -EINVAL;
148
149 ret = sclp_pci_report(report, zdev->fh, zdev->fid);
150
151 return ret ? ret : count;
152 }
153 static BIN_ATTR(report_error, S_IWUSR, NULL, report_error_write, PAGE_SIZE);
154
uid_is_unique_show(struct device * dev,struct device_attribute * attr,char * buf)155 static ssize_t uid_is_unique_show(struct device *dev,
156 struct device_attribute *attr, char *buf)
157 {
158 return sysfs_emit(buf, "%d\n", zpci_unique_uid ? 1 : 0);
159 }
160 static DEVICE_ATTR_RO(uid_is_unique);
161
162 #ifndef CONFIG_DMI
163 /* analogous to smbios index */
index_show(struct device * dev,struct device_attribute * attr,char * buf)164 static ssize_t index_show(struct device *dev,
165 struct device_attribute *attr, char *buf)
166 {
167 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
168 u32 index = ~0;
169
170 if (zpci_unique_uid)
171 index = zdev->uid;
172
173 return sysfs_emit(buf, "%u\n", index);
174 }
175 static DEVICE_ATTR_RO(index);
176
zpci_index_is_visible(struct kobject * kobj,struct attribute * attr,int n)177 static umode_t zpci_index_is_visible(struct kobject *kobj,
178 struct attribute *attr, int n)
179 {
180 return zpci_unique_uid ? attr->mode : 0;
181 }
182
183 static struct attribute *zpci_ident_attrs[] = {
184 &dev_attr_index.attr,
185 NULL,
186 };
187
188 static struct attribute_group zpci_ident_attr_group = {
189 .attrs = zpci_ident_attrs,
190 .is_visible = zpci_index_is_visible,
191 };
192 #endif
193
194 static struct bin_attribute *zpci_bin_attrs[] = {
195 &bin_attr_util_string,
196 &bin_attr_report_error,
197 NULL,
198 };
199
200 static struct attribute *zpci_dev_attrs[] = {
201 &dev_attr_function_id.attr,
202 &dev_attr_function_handle.attr,
203 &dev_attr_pchid.attr,
204 &dev_attr_pfgid.attr,
205 &dev_attr_pft.attr,
206 &dev_attr_port.attr,
207 &dev_attr_vfn.attr,
208 &dev_attr_uid.attr,
209 &dev_attr_recover.attr,
210 &dev_attr_mio_enabled.attr,
211 &dev_attr_uid_is_unique.attr,
212 NULL,
213 };
214
215 static struct attribute_group zpci_attr_group = {
216 .attrs = zpci_dev_attrs,
217 .bin_attrs = zpci_bin_attrs,
218 };
219
220 static struct attribute *pfip_attrs[] = {
221 &dev_attr_segment0.attr,
222 &dev_attr_segment1.attr,
223 &dev_attr_segment2.attr,
224 &dev_attr_segment3.attr,
225 NULL,
226 };
227 static struct attribute_group pfip_attr_group = {
228 .name = "pfip",
229 .attrs = pfip_attrs,
230 };
231
232 const struct attribute_group *zpci_attr_groups[] = {
233 &zpci_attr_group,
234 &pfip_attr_group,
235 #ifndef CONFIG_DMI
236 &zpci_ident_attr_group,
237 #endif
238 NULL,
239 };
240