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 sysfs_emit(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(fidparm, "0x%02x\n", fidparm);
38 zpci_attr(uid, "0x%x\n", uid);
39 zpci_attr(segment0, "0x%02x\n", pfip[0]);
40 zpci_attr(segment1, "0x%02x\n", pfip[1]);
41 zpci_attr(segment2, "0x%02x\n", pfip[2]);
42 zpci_attr(segment3, "0x%02x\n", pfip[3]);
43
mio_enabled_show(struct device * dev,struct device_attribute * attr,char * buf)44 static ssize_t mio_enabled_show(struct device *dev,
45 struct device_attribute *attr, char *buf)
46 {
47 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
48
49 return sysfs_emit(buf, zpci_use_mio(zdev) ? "1\n" : "0\n");
50 }
51 static DEVICE_ATTR_RO(mio_enabled);
52
_do_recover(struct pci_dev * pdev,struct zpci_dev * zdev)53 static int _do_recover(struct pci_dev *pdev, struct zpci_dev *zdev)
54 {
55 u8 status;
56 int ret;
57
58 pci_stop_and_remove_bus_device(pdev);
59 if (zdev_enabled(zdev)) {
60 ret = zpci_disable_device(zdev);
61 /*
62 * Due to a z/VM vs LPAR inconsistency in the error
63 * state the FH may indicate an enabled device but
64 * disable says the device is already disabled don't
65 * treat it as an error here.
66 */
67 if (ret == -EINVAL)
68 ret = 0;
69 if (ret)
70 return ret;
71 }
72
73 ret = zpci_enable_device(zdev);
74 if (ret)
75 return ret;
76
77 if (zdev->dma_table) {
78 ret = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
79 virt_to_phys(zdev->dma_table), &status);
80 if (ret)
81 zpci_disable_device(zdev);
82 }
83 return ret;
84 }
85
recover_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)86 static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
87 const char *buf, size_t count)
88 {
89 struct kernfs_node *kn;
90 struct pci_dev *pdev = to_pci_dev(dev);
91 struct zpci_dev *zdev = to_zpci(pdev);
92 int ret = 0;
93
94 /* Can't use device_remove_self() here as that would lead us to lock
95 * the pci_rescan_remove_lock while holding the device' kernfs lock.
96 * This would create a possible deadlock with disable_slot() which is
97 * not directly protected by the device' kernfs lock but takes it
98 * during the device removal which happens under
99 * pci_rescan_remove_lock.
100 *
101 * This is analogous to sdev_store_delete() in
102 * drivers/scsi/scsi_sysfs.c
103 */
104 kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
105 WARN_ON_ONCE(!kn);
106
107 /* Device needs to be configured and state must not change */
108 mutex_lock(&zdev->state_lock);
109 if (zdev->state != ZPCI_FN_STATE_CONFIGURED)
110 goto out;
111
112 /* device_remove_file() serializes concurrent calls ignoring all but
113 * the first
114 */
115 device_remove_file(dev, attr);
116
117 /* A concurrent call to recover_store() may slip between
118 * sysfs_break_active_protection() and the sysfs file removal.
119 * Once it unblocks from pci_lock_rescan_remove() the original pdev
120 * will already be removed.
121 */
122 pci_lock_rescan_remove();
123 if (pci_dev_is_added(pdev)) {
124 ret = _do_recover(pdev, zdev);
125 }
126 pci_rescan_bus(zdev->zbus->bus);
127 pci_unlock_rescan_remove();
128
129 out:
130 mutex_unlock(&zdev->state_lock);
131 if (kn)
132 sysfs_unbreak_active_protection(kn);
133 return ret ? ret : count;
134 }
135 static DEVICE_ATTR_WO(recover);
136
util_string_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)137 static ssize_t util_string_read(struct file *filp, struct kobject *kobj,
138 struct bin_attribute *attr, char *buf,
139 loff_t off, size_t count)
140 {
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
145 return memory_read_from_buffer(buf, count, &off, zdev->util_str,
146 sizeof(zdev->util_str));
147 }
148 static BIN_ATTR_RO(util_string, CLP_UTIL_STR_LEN);
149
report_error_write(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)150 static ssize_t report_error_write(struct file *filp, struct kobject *kobj,
151 struct bin_attribute *attr, char *buf,
152 loff_t off, size_t count)
153 {
154 struct zpci_report_error_header *report = (void *) buf;
155 struct device *dev = kobj_to_dev(kobj);
156 struct pci_dev *pdev = to_pci_dev(dev);
157 struct zpci_dev *zdev = to_zpci(pdev);
158 int ret;
159
160 if (off || (count < sizeof(*report)))
161 return -EINVAL;
162
163 ret = sclp_pci_report(report, zdev->fh, zdev->fid);
164
165 return ret ? ret : count;
166 }
167 static BIN_ATTR(report_error, S_IWUSR, NULL, report_error_write, PAGE_SIZE);
168
uid_is_unique_show(struct device * dev,struct device_attribute * attr,char * buf)169 static ssize_t uid_is_unique_show(struct device *dev,
170 struct device_attribute *attr, char *buf)
171 {
172 return sysfs_emit(buf, "%d\n", zpci_unique_uid ? 1 : 0);
173 }
174 static DEVICE_ATTR_RO(uid_is_unique);
175
176 /* analogous to smbios index */
index_show(struct device * dev,struct device_attribute * attr,char * buf)177 static ssize_t index_show(struct device *dev,
178 struct device_attribute *attr, char *buf)
179 {
180 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
181 u32 index = ~0;
182
183 if (zpci_unique_uid)
184 index = zdev->uid;
185
186 return sysfs_emit(buf, "%u\n", index);
187 }
188 static DEVICE_ATTR_RO(index);
189
zpci_index_is_visible(struct kobject * kobj,struct attribute * attr,int n)190 static umode_t zpci_index_is_visible(struct kobject *kobj,
191 struct attribute *attr, int n)
192 {
193 return zpci_unique_uid ? attr->mode : 0;
194 }
195
196 static struct attribute *zpci_ident_attrs[] = {
197 &dev_attr_index.attr,
198 NULL,
199 };
200
201 const struct attribute_group zpci_ident_attr_group = {
202 .attrs = zpci_ident_attrs,
203 .is_visible = zpci_index_is_visible,
204 };
205
206 static struct bin_attribute *zpci_bin_attrs[] = {
207 &bin_attr_util_string,
208 &bin_attr_report_error,
209 NULL,
210 };
211
212 static struct attribute *zpci_dev_attrs[] = {
213 &dev_attr_function_id.attr,
214 &dev_attr_function_handle.attr,
215 &dev_attr_pchid.attr,
216 &dev_attr_pfgid.attr,
217 &dev_attr_pft.attr,
218 &dev_attr_port.attr,
219 &dev_attr_fidparm.attr,
220 &dev_attr_vfn.attr,
221 &dev_attr_uid.attr,
222 &dev_attr_recover.attr,
223 &dev_attr_mio_enabled.attr,
224 &dev_attr_uid_is_unique.attr,
225 NULL,
226 };
227
228 const struct attribute_group zpci_attr_group = {
229 .attrs = zpci_dev_attrs,
230 .bin_attrs = zpci_bin_attrs,
231 };
232
233 static struct attribute *pfip_attrs[] = {
234 &dev_attr_segment0.attr,
235 &dev_attr_segment1.attr,
236 &dev_attr_segment2.attr,
237 &dev_attr_segment3.attr,
238 NULL,
239 };
240
241 const struct attribute_group pfip_attr_group = {
242 .name = "pfip",
243 .attrs = pfip_attrs,
244 };
245