1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * SCLP OCF communication parameters sysfs interface 4 * 5 * Copyright IBM Corp. 2011 6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 7 */ 8 9 #define KMSG_COMPONENT "sclp_ocf" 10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 11 12 #include <linux/export.h> 13 #include <linux/kernel.h> 14 #include <linux/init.h> 15 #include <linux/stat.h> 16 #include <linux/device.h> 17 #include <linux/string.h> 18 #include <linux/ctype.h> 19 #include <linux/kmod.h> 20 #include <linux/timer.h> 21 #include <linux/err.h> 22 #include <asm/ebcdic.h> 23 #include <asm/sclp.h> 24 25 #include "sclp.h" 26 27 #define OCF_LENGTH_HMC_NETWORK 8UL 28 #define OCF_LENGTH_CPC_NAME 8UL 29 30 static char hmc_network[OCF_LENGTH_HMC_NETWORK + 1]; 31 static char cpc_name[OCF_LENGTH_CPC_NAME]; /* in EBCDIC */ 32 33 static DEFINE_SPINLOCK(sclp_ocf_lock); 34 static struct work_struct sclp_ocf_change_work; 35 36 static struct kset *ocf_kset; 37 38 static void sclp_ocf_change_notify(struct work_struct *work) 39 { 40 kobject_uevent(&ocf_kset->kobj, KOBJ_CHANGE); 41 } 42 43 /* Handler for OCF event. Look for the CPC image name. */ 44 static void sclp_ocf_handler(struct evbuf_header *evbuf) 45 { 46 struct gds_vector *v; 47 struct gds_subvector *sv, *netid, *cpc; 48 size_t size; 49 50 /* Find the 0x9f00 block. */ 51 v = sclp_find_gds_vector(evbuf + 1, (void *) evbuf + evbuf->length, 52 0x9f00); 53 if (!v) 54 return; 55 /* Find the 0x9f22 block inside the 0x9f00 block. */ 56 v = sclp_find_gds_vector(v + 1, (void *) v + v->length, 0x9f22); 57 if (!v) 58 return; 59 /* Find the 0x81 block inside the 0x9f22 block. */ 60 sv = sclp_find_gds_subvector(v + 1, (void *) v + v->length, 0x81); 61 if (!sv) 62 return; 63 /* Find the 0x01 block inside the 0x81 block. */ 64 netid = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 1); 65 /* Find the 0x02 block inside the 0x81 block. */ 66 cpc = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 2); 67 /* Copy network name and cpc name. */ 68 spin_lock(&sclp_ocf_lock); 69 if (netid) { 70 size = min(OCF_LENGTH_HMC_NETWORK, (size_t) netid->length); 71 memcpy(hmc_network, netid + 1, size); 72 EBCASC(hmc_network, size); 73 hmc_network[size] = 0; 74 } 75 if (cpc) { 76 size = min(OCF_LENGTH_CPC_NAME, (size_t) cpc->length); 77 memset(cpc_name, 0, OCF_LENGTH_CPC_NAME); 78 memcpy(cpc_name, cpc + 1, size); 79 } 80 spin_unlock(&sclp_ocf_lock); 81 schedule_work(&sclp_ocf_change_work); 82 } 83 84 static struct sclp_register sclp_ocf_event = { 85 .receive_mask = EVTYP_OCF_MASK, 86 .receiver_fn = sclp_ocf_handler, 87 }; 88 89 void sclp_ocf_cpc_name_copy(char *dst) 90 { 91 spin_lock_irq(&sclp_ocf_lock); 92 memcpy(dst, cpc_name, OCF_LENGTH_CPC_NAME); 93 spin_unlock_irq(&sclp_ocf_lock); 94 } 95 EXPORT_SYMBOL(sclp_ocf_cpc_name_copy); 96 97 static ssize_t cpc_name_show(struct kobject *kobj, 98 struct kobj_attribute *attr, char *page) 99 { 100 char name[OCF_LENGTH_CPC_NAME + 1]; 101 102 sclp_ocf_cpc_name_copy(name); 103 name[OCF_LENGTH_CPC_NAME] = 0; 104 EBCASC(name, OCF_LENGTH_CPC_NAME); 105 return sysfs_emit(page, "%s\n", name); 106 } 107 108 static struct kobj_attribute cpc_name_attr = 109 __ATTR(cpc_name, 0444, cpc_name_show, NULL); 110 111 static ssize_t hmc_network_show(struct kobject *kobj, 112 struct kobj_attribute *attr, char *page) 113 { 114 int rc; 115 116 spin_lock_irq(&sclp_ocf_lock); 117 rc = sysfs_emit(page, "%s\n", hmc_network); 118 spin_unlock_irq(&sclp_ocf_lock); 119 return rc; 120 } 121 122 static struct kobj_attribute hmc_network_attr = 123 __ATTR(hmc_network, 0444, hmc_network_show, NULL); 124 125 static struct attribute *ocf_attrs[] = { 126 &cpc_name_attr.attr, 127 &hmc_network_attr.attr, 128 NULL, 129 }; 130 131 static const struct attribute_group ocf_attr_group = { 132 .attrs = ocf_attrs, 133 }; 134 135 static int __init ocf_init(void) 136 { 137 int rc; 138 139 INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify); 140 ocf_kset = kset_create_and_add("ocf", NULL, firmware_kobj); 141 if (!ocf_kset) 142 return -ENOMEM; 143 144 rc = sysfs_create_group(&ocf_kset->kobj, &ocf_attr_group); 145 if (rc) { 146 kset_unregister(ocf_kset); 147 return rc; 148 } 149 150 return sclp_register(&sclp_ocf_event); 151 } 152 153 device_initcall(ocf_init); 154