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 ret = zpci_disable_device(zdev);
86 if (ret)
87 goto out;
88
89 ret = zpci_enable_device(zdev);
90 if (ret)
91 goto out;
92 pci_rescan_bus(zdev->zbus->bus);
93 }
94 out:
95 pci_unlock_rescan_remove();
96 if (kn)
97 sysfs_unbreak_active_protection(kn);
98 return ret ? ret : count;
99 }
100 static DEVICE_ATTR_WO(recover);
101
util_string_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)102 static ssize_t util_string_read(struct file *filp, struct kobject *kobj,
103 struct bin_attribute *attr, char *buf,
104 loff_t off, size_t count)
105 {
106 struct device *dev = kobj_to_dev(kobj);
107 struct pci_dev *pdev = to_pci_dev(dev);
108 struct zpci_dev *zdev = to_zpci(pdev);
109
110 return memory_read_from_buffer(buf, count, &off, zdev->util_str,
111 sizeof(zdev->util_str));
112 }
113 static BIN_ATTR_RO(util_string, CLP_UTIL_STR_LEN);
114
report_error_write(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)115 static ssize_t report_error_write(struct file *filp, struct kobject *kobj,
116 struct bin_attribute *attr, char *buf,
117 loff_t off, size_t count)
118 {
119 struct zpci_report_error_header *report = (void *) buf;
120 struct device *dev = kobj_to_dev(kobj);
121 struct pci_dev *pdev = to_pci_dev(dev);
122 struct zpci_dev *zdev = to_zpci(pdev);
123 int ret;
124
125 if (off || (count < sizeof(*report)))
126 return -EINVAL;
127
128 ret = sclp_pci_report(report, zdev->fh, zdev->fid);
129
130 return ret ? ret : count;
131 }
132 static BIN_ATTR(report_error, S_IWUSR, NULL, report_error_write, PAGE_SIZE);
133
134 static struct bin_attribute *zpci_bin_attrs[] = {
135 &bin_attr_util_string,
136 &bin_attr_report_error,
137 NULL,
138 };
139
140 static struct attribute *zpci_dev_attrs[] = {
141 &dev_attr_function_id.attr,
142 &dev_attr_function_handle.attr,
143 &dev_attr_pchid.attr,
144 &dev_attr_pfgid.attr,
145 &dev_attr_pft.attr,
146 &dev_attr_port.attr,
147 &dev_attr_vfn.attr,
148 &dev_attr_uid.attr,
149 &dev_attr_recover.attr,
150 &dev_attr_mio_enabled.attr,
151 NULL,
152 };
153 static struct attribute_group zpci_attr_group = {
154 .attrs = zpci_dev_attrs,
155 .bin_attrs = zpci_bin_attrs,
156 };
157
158 static struct attribute *pfip_attrs[] = {
159 &dev_attr_segment0.attr,
160 &dev_attr_segment1.attr,
161 &dev_attr_segment2.attr,
162 &dev_attr_segment3.attr,
163 NULL,
164 };
165 static struct attribute_group pfip_attr_group = {
166 .name = "pfip",
167 .attrs = pfip_attrs,
168 };
169
170 const struct attribute_group *zpci_attr_groups[] = {
171 &zpci_attr_group,
172 &pfip_attr_group,
173 NULL,
174 };
175