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 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 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 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); 136 137 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); 149 150 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); 168 169 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 */ 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); 189 190 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