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