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(uid, "0x%x\n", uid); 37 zpci_attr(segment0, "0x%02x\n", pfip[0]); 38 zpci_attr(segment1, "0x%02x\n", pfip[1]); 39 zpci_attr(segment2, "0x%02x\n", pfip[2]); 40 zpci_attr(segment3, "0x%02x\n", pfip[3]); 41 42 static ssize_t mio_enabled_show(struct device *dev, 43 struct device_attribute *attr, char *buf) 44 { 45 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev)); 46 47 return sprintf(buf, zpci_use_mio(zdev) ? "1\n" : "0\n"); 48 } 49 static DEVICE_ATTR_RO(mio_enabled); 50 51 static ssize_t recover_store(struct device *dev, struct device_attribute *attr, 52 const char *buf, size_t count) 53 { 54 struct kernfs_node *kn; 55 struct pci_dev *pdev = to_pci_dev(dev); 56 struct zpci_dev *zdev = to_zpci(pdev); 57 int ret = 0; 58 59 /* Can't use device_remove_self() here as that would lead us to lock 60 * the pci_rescan_remove_lock while holding the device' kernfs lock. 61 * This would create a possible deadlock with disable_slot() which is 62 * not directly protected by the device' kernfs lock but takes it 63 * during the device removal which happens under 64 * pci_rescan_remove_lock. 65 * 66 * This is analogous to sdev_store_delete() in 67 * drivers/scsi/scsi_sysfs.c 68 */ 69 kn = sysfs_break_active_protection(&dev->kobj, &attr->attr); 70 WARN_ON_ONCE(!kn); 71 /* device_remove_file() serializes concurrent calls ignoring all but 72 * the first 73 */ 74 device_remove_file(dev, attr); 75 76 /* A concurrent call to recover_store() may slip between 77 * sysfs_break_active_protection() and the sysfs file removal. 78 * Once it unblocks from pci_lock_rescan_remove() the original pdev 79 * will already be removed. 80 */ 81 pci_lock_rescan_remove(); 82 if (pci_dev_is_added(pdev)) { 83 pci_stop_and_remove_bus_device(pdev); 84 ret = zpci_disable_device(zdev); 85 if (ret) 86 goto out; 87 88 ret = zpci_enable_device(zdev); 89 if (ret) 90 goto out; 91 pci_rescan_bus(zdev->bus); 92 } 93 out: 94 pci_unlock_rescan_remove(); 95 if (kn) 96 sysfs_unbreak_active_protection(kn); 97 return ret ? ret : count; 98 } 99 static DEVICE_ATTR_WO(recover); 100 101 static ssize_t util_string_read(struct file *filp, struct kobject *kobj, 102 struct bin_attribute *attr, char *buf, 103 loff_t off, size_t count) 104 { 105 struct device *dev = kobj_to_dev(kobj); 106 struct pci_dev *pdev = to_pci_dev(dev); 107 struct zpci_dev *zdev = to_zpci(pdev); 108 109 return memory_read_from_buffer(buf, count, &off, zdev->util_str, 110 sizeof(zdev->util_str)); 111 } 112 static BIN_ATTR_RO(util_string, CLP_UTIL_STR_LEN); 113 114 static ssize_t report_error_write(struct file *filp, struct kobject *kobj, 115 struct bin_attribute *attr, char *buf, 116 loff_t off, size_t count) 117 { 118 struct zpci_report_error_header *report = (void *) buf; 119 struct device *dev = kobj_to_dev(kobj); 120 struct pci_dev *pdev = to_pci_dev(dev); 121 struct zpci_dev *zdev = to_zpci(pdev); 122 int ret; 123 124 if (off || (count < sizeof(*report))) 125 return -EINVAL; 126 127 ret = sclp_pci_report(report, zdev->fh, zdev->fid); 128 129 return ret ? ret : count; 130 } 131 static BIN_ATTR(report_error, S_IWUSR, NULL, report_error_write, PAGE_SIZE); 132 133 static struct bin_attribute *zpci_bin_attrs[] = { 134 &bin_attr_util_string, 135 &bin_attr_report_error, 136 NULL, 137 }; 138 139 static struct attribute *zpci_dev_attrs[] = { 140 &dev_attr_function_id.attr, 141 &dev_attr_function_handle.attr, 142 &dev_attr_pchid.attr, 143 &dev_attr_pfgid.attr, 144 &dev_attr_pft.attr, 145 &dev_attr_vfn.attr, 146 &dev_attr_uid.attr, 147 &dev_attr_recover.attr, 148 &dev_attr_mio_enabled.attr, 149 NULL, 150 }; 151 static struct attribute_group zpci_attr_group = { 152 .attrs = zpci_dev_attrs, 153 .bin_attrs = zpci_bin_attrs, 154 }; 155 156 static struct attribute *pfip_attrs[] = { 157 &dev_attr_segment0.attr, 158 &dev_attr_segment1.attr, 159 &dev_attr_segment2.attr, 160 &dev_attr_segment3.attr, 161 NULL, 162 }; 163 static struct attribute_group pfip_attr_group = { 164 .name = "pfip", 165 .attrs = pfip_attrs, 166 }; 167 168 const struct attribute_group *zpci_attr_groups[] = { 169 &zpci_attr_group, 170 &pfip_attr_group, 171 NULL, 172 }; 173