1 /* 2 * drivers/s390/char/sclp_ocf.c 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 + 1]; 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 memcpy(cpc_name, cpc + 1, size); 77 EBCASC(cpc_name, size); 78 cpc_name[size] = 0; 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 static ssize_t cpc_name_show(struct kobject *kobj, 90 struct kobj_attribute *attr, char *page) 91 { 92 int rc; 93 94 spin_lock_irq(&sclp_ocf_lock); 95 rc = snprintf(page, PAGE_SIZE, "%s\n", cpc_name); 96 spin_unlock_irq(&sclp_ocf_lock); 97 return rc; 98 } 99 100 static struct kobj_attribute cpc_name_attr = 101 __ATTR(cpc_name, 0444, cpc_name_show, NULL); 102 103 static ssize_t hmc_network_show(struct kobject *kobj, 104 struct kobj_attribute *attr, char *page) 105 { 106 int rc; 107 108 spin_lock_irq(&sclp_ocf_lock); 109 rc = snprintf(page, PAGE_SIZE, "%s\n", hmc_network); 110 spin_unlock_irq(&sclp_ocf_lock); 111 return rc; 112 } 113 114 static struct kobj_attribute hmc_network_attr = 115 __ATTR(hmc_network, 0444, hmc_network_show, NULL); 116 117 static struct attribute *ocf_attrs[] = { 118 &cpc_name_attr.attr, 119 &hmc_network_attr.attr, 120 NULL, 121 }; 122 123 static struct attribute_group ocf_attr_group = { 124 .attrs = ocf_attrs, 125 }; 126 127 static int __init ocf_init(void) 128 { 129 int rc; 130 131 INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify); 132 ocf_kset = kset_create_and_add("ocf", NULL, firmware_kobj); 133 if (!ocf_kset) 134 return -ENOMEM; 135 136 rc = sysfs_create_group(&ocf_kset->kobj, &ocf_attr_group); 137 if (rc) { 138 kset_unregister(ocf_kset); 139 return rc; 140 } 141 142 return sclp_register(&sclp_ocf_event); 143 } 144 145 device_initcall(ocf_init); 146