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) \ 21static 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} \ 28static DEVICE_ATTR_RO(name) 29 30zpci_attr(function_id, "0x%08x\n", fid); 31zpci_attr(function_handle, "0x%08x\n", fh); 32zpci_attr(pchid, "0x%04x\n", pchid); 33zpci_attr(pfgid, "0x%02x\n", pfgid); 34zpci_attr(vfn, "0x%04x\n", vfn); 35zpci_attr(pft, "0x%02x\n", pft); 36zpci_attr(port, "%d\n", port); 37zpci_attr(uid, "0x%x\n", uid); 38zpci_attr(segment0, "0x%02x\n", pfip[0]); 39zpci_attr(segment1, "0x%02x\n", pfip[1]); 40zpci_attr(segment2, "0x%02x\n", pfip[2]); 41zpci_attr(segment3, "0x%02x\n", pfip[3]); 42 43static 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} 50static DEVICE_ATTR_RO(mio_enabled); 51 52static int _do_recover(struct pci_dev *pdev, struct zpci_dev *zdev) 53{ 54 u8 status; 55 int ret; 56 57 pci_stop_and_remove_bus_device(pdev); 58 if (zdev_enabled(zdev)) { 59 ret = zpci_disable_device(zdev); 60 /* 61 * Due to a z/VM vs LPAR inconsistency in the error 62 * state the FH may indicate an enabled device but 63 * disable says the device is already disabled don't 64 * treat it as an error here. 65 */ 66 if (ret == -EINVAL) 67 ret = 0; 68 if (ret) 69 return ret; 70 } 71 72 ret = zpci_enable_device(zdev); 73 if (ret) 74 return ret; 75 76 if (zdev->dma_table) { 77 ret = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma, 78 virt_to_phys(zdev->dma_table), &status); 79 if (ret) 80 zpci_disable_device(zdev); 81 } 82 return ret; 83} 84 85static ssize_t recover_store(struct device *dev, struct device_attribute *attr, 86 const char *buf, size_t count) 87{ 88 struct kernfs_node *kn; 89 struct pci_dev *pdev = to_pci_dev(dev); 90 struct zpci_dev *zdev = to_zpci(pdev); 91 int ret = 0; 92 93 /* Can't use device_remove_self() here as that would lead us to lock 94 * the pci_rescan_remove_lock while holding the device' kernfs lock. 95 * This would create a possible deadlock with disable_slot() which is 96 * not directly protected by the device' kernfs lock but takes it 97 * during the device removal which happens under 98 * pci_rescan_remove_lock. 99 * 100 * This is analogous to sdev_store_delete() in 101 * drivers/scsi/scsi_sysfs.c 102 */ 103 kn = sysfs_break_active_protection(&dev->kobj, &attr->attr); 104 WARN_ON_ONCE(!kn); 105 106 /* Device needs to be configured and state must not change */ 107 mutex_lock(&zdev->state_lock); 108 if (zdev->state != ZPCI_FN_STATE_CONFIGURED) 109 goto out; 110 111 /* device_remove_file() serializes concurrent calls ignoring all but 112 * the first 113 */ 114 device_remove_file(dev, attr); 115 116 /* A concurrent call to recover_store() may slip between 117 * sysfs_break_active_protection() and the sysfs file removal. 118 * Once it unblocks from pci_lock_rescan_remove() the original pdev 119 * will already be removed. 120 */ 121 pci_lock_rescan_remove(); 122 if (pci_dev_is_added(pdev)) { 123 ret = _do_recover(pdev, zdev); 124 } 125 pci_rescan_bus(zdev->zbus->bus); 126 pci_unlock_rescan_remove(); 127 128out: 129 mutex_unlock(&zdev->state_lock); 130 if (kn) 131 sysfs_unbreak_active_protection(kn); 132 return ret ? ret : count; 133} 134static DEVICE_ATTR_WO(recover); 135 136static ssize_t util_string_read(struct file *filp, struct kobject *kobj, 137 struct bin_attribute *attr, char *buf, 138 loff_t off, size_t count) 139{ 140 struct device *dev = kobj_to_dev(kobj); 141 struct pci_dev *pdev = to_pci_dev(dev); 142 struct zpci_dev *zdev = to_zpci(pdev); 143 144 return memory_read_from_buffer(buf, count, &off, zdev->util_str, 145 sizeof(zdev->util_str)); 146} 147static BIN_ATTR_RO(util_string, CLP_UTIL_STR_LEN); 148 149static ssize_t report_error_write(struct file *filp, struct kobject *kobj, 150 struct bin_attribute *attr, char *buf, 151 loff_t off, size_t count) 152{ 153 struct zpci_report_error_header *report = (void *) buf; 154 struct device *dev = kobj_to_dev(kobj); 155 struct pci_dev *pdev = to_pci_dev(dev); 156 struct zpci_dev *zdev = to_zpci(pdev); 157 int ret; 158 159 if (off || (count < sizeof(*report))) 160 return -EINVAL; 161 162 ret = sclp_pci_report(report, zdev->fh, zdev->fid); 163 164 return ret ? ret : count; 165} 166static BIN_ATTR(report_error, S_IWUSR, NULL, report_error_write, PAGE_SIZE); 167 168static ssize_t uid_is_unique_show(struct device *dev, 169 struct device_attribute *attr, char *buf) 170{ 171 return sysfs_emit(buf, "%d\n", zpci_unique_uid ? 1 : 0); 172} 173static DEVICE_ATTR_RO(uid_is_unique); 174 175#ifndef CONFIG_DMI 176/* analogous to smbios index */ 177static 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} 188static DEVICE_ATTR_RO(index); 189 190static 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 196static struct attribute *zpci_ident_attrs[] = { 197 &dev_attr_index.attr, 198 NULL, 199}; 200 201static struct attribute_group zpci_ident_attr_group = { 202 .attrs = zpci_ident_attrs, 203 .is_visible = zpci_index_is_visible, 204}; 205#endif 206 207static struct bin_attribute *zpci_bin_attrs[] = { 208 &bin_attr_util_string, 209 &bin_attr_report_error, 210 NULL, 211}; 212 213static struct attribute *zpci_dev_attrs[] = { 214 &dev_attr_function_id.attr, 215 &dev_attr_function_handle.attr, 216 &dev_attr_pchid.attr, 217 &dev_attr_pfgid.attr, 218 &dev_attr_pft.attr, 219 &dev_attr_port.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 228static struct attribute_group zpci_attr_group = { 229 .attrs = zpci_dev_attrs, 230 .bin_attrs = zpci_bin_attrs, 231}; 232 233static 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}; 240static struct attribute_group pfip_attr_group = { 241 .name = "pfip", 242 .attrs = pfip_attrs, 243}; 244 245const struct attribute_group *zpci_attr_groups[] = { 246 &zpci_attr_group, 247 &pfip_attr_group, 248#ifndef CONFIG_DMI 249 &zpci_ident_attr_group, 250#endif 251 NULL, 252}; 253