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