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 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 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); 101 102 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); 114 115 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