[S390] sclp: sysfs interface for SCLP cpi

Signed-off-by: Michael Ernst <mernst@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/char/sclp_cpi_sys.c b/drivers/s390/char/sclp_cpi_sys.c
new file mode 100644
index 0000000..4161703
--- /dev/null
+++ b/drivers/s390/char/sclp_cpi_sys.c
@@ -0,0 +1,400 @@
+/*
+ *  drivers/s390/char/sclp_cpi_sys.c
+ *    SCLP control program identification sysfs interface
+ *
+ *    Copyright IBM Corp. 2001, 2007
+ *    Author(s): Martin Peschke <mpeschke@de.ibm.com>
+ *		 Michael Ernst <mernst@de.ibm.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/stat.h>
+#include <linux/device.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/kmod.h>
+#include <linux/timer.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/completion.h>
+#include <asm/ebcdic.h>
+#include <asm/sclp.h>
+#include "sclp.h"
+#include "sclp_rw.h"
+#include "sclp_cpi_sys.h"
+
+#define CPI_LENGTH_NAME 8
+#define CPI_LENGTH_LEVEL 16
+
+struct cpi_evbuf {
+	struct evbuf_header header;
+	u8	id_format;
+	u8	reserved0;
+	u8	system_type[CPI_LENGTH_NAME];
+	u64	reserved1;
+	u8	system_name[CPI_LENGTH_NAME];
+	u64	reserved2;
+	u64	system_level;
+	u64	reserved3;
+	u8	sysplex_name[CPI_LENGTH_NAME];
+	u8	reserved4[16];
+} __attribute__((packed));
+
+struct cpi_sccb {
+	struct sccb_header header;
+	struct cpi_evbuf cpi_evbuf;
+} __attribute__((packed));
+
+static struct sclp_register sclp_cpi_event = {
+	.send_mask = EVTYP_CTLPROGIDENT_MASK,
+};
+
+static char system_name[CPI_LENGTH_NAME + 1];
+static char sysplex_name[CPI_LENGTH_NAME + 1];
+static char system_type[CPI_LENGTH_NAME + 1];
+static u64 system_level;
+
+static void set_data(char *field, char *data)
+{
+	memset(field, ' ', CPI_LENGTH_NAME);
+	memcpy(field, data, strlen(data));
+	sclp_ascebc_str(field, CPI_LENGTH_NAME);
+}
+
+static void cpi_callback(struct sclp_req *req, void *data)
+{
+	struct completion *completion = data;
+
+	complete(completion);
+}
+
+static struct sclp_req *cpi_prepare_req(void)
+{
+	struct sclp_req *req;
+	struct cpi_sccb *sccb;
+	struct cpi_evbuf *evb;
+
+	req = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
+	if (!req)
+		return ERR_PTR(-ENOMEM);
+	sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	if (!sccb) {
+		kfree(req);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	/* setup SCCB for Control-Program Identification */
+	sccb->header.length = sizeof(struct cpi_sccb);
+	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
+	sccb->cpi_evbuf.header.type = 0x0b;
+	evb = &sccb->cpi_evbuf;
+
+	/* set system type */
+	set_data(evb->system_type, system_type);
+
+	/* set system name */
+	set_data(evb->system_name, system_name);
+
+	/* set sytem level */
+	evb->system_level = system_level;
+
+	/* set sysplex name */
+	set_data(evb->sysplex_name, sysplex_name);
+
+	/* prepare request data structure presented to SCLP driver */
+	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
+	req->sccb = sccb;
+	req->status = SCLP_REQ_FILLED;
+	req->callback = cpi_callback;
+	return req;
+}
+
+static void cpi_free_req(struct sclp_req *req)
+{
+	free_page((unsigned long) req->sccb);
+	kfree(req);
+}
+
+static int cpi_req(void)
+{
+	struct completion completion;
+	struct sclp_req *req;
+	int rc;
+	int response;
+
+	rc = sclp_register(&sclp_cpi_event);
+	if (rc) {
+		printk(KERN_WARNING "cpi: could not register "
+			"to hardware console.\n");
+		goto out;
+	}
+	if (!(sclp_cpi_event.sclp_send_mask & EVTYP_CTLPROGIDENT_MASK)) {
+		printk(KERN_WARNING "cpi: no control program "
+			"identification support\n");
+		rc = -EOPNOTSUPP;
+		goto out_unregister;
+	}
+
+	req = cpi_prepare_req();
+	if (IS_ERR(req)) {
+		printk(KERN_WARNING "cpi: could not allocate request\n");
+		rc = PTR_ERR(req);
+		goto out_unregister;
+	}
+
+	init_completion(&completion);
+	req->callback_data = &completion;
+
+	/* Add request to sclp queue */
+	rc = sclp_add_request(req);
+	if (rc) {
+		printk(KERN_WARNING "cpi: could not start request\n");
+		goto out_free_req;
+	}
+
+	wait_for_completion(&completion);
+
+	if (req->status != SCLP_REQ_DONE) {
+		printk(KERN_WARNING "cpi: request failed (status=0x%02x)\n",
+			req->status);
+		rc = -EIO;
+		goto out_free_req;
+	}
+
+	response = ((struct cpi_sccb *) req->sccb)->header.response_code;
+	if (response != 0x0020) {
+		printk(KERN_WARNING "cpi: failed with "
+			"response code 0x%x\n", response);
+		rc = -EIO;
+	}
+
+out_free_req:
+	cpi_free_req(req);
+
+out_unregister:
+	sclp_unregister(&sclp_cpi_event);
+
+out:
+	return rc;
+}
+
+static int check_string(const char *attr, const char *str)
+{
+	size_t len;
+	size_t i;
+
+	len = strlen(str);
+
+	if ((len > 0) && (str[len - 1] == '\n'))
+		len--;
+
+	if (len > CPI_LENGTH_NAME)
+		return -EINVAL;
+
+	for (i = 0; i < len ; i++) {
+		if (isalpha(str[i]) || isdigit(str[i]) ||
+		    strchr("$@# ", str[i]))
+			continue;
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void set_string(char *attr, const char *value)
+{
+	size_t len;
+	size_t i;
+
+	len = strlen(value);
+
+	if ((len > 0) && (value[len - 1] == '\n'))
+		len--;
+
+	for (i = 0; i < CPI_LENGTH_NAME; i++) {
+		if (i < len)
+			attr[i] = toupper(value[i]);
+		else
+			attr[i] = ' ';
+	}
+}
+
+static ssize_t system_name_show(struct kobject *kobj,
+				struct kobj_attribute *attr, char *page)
+{
+	return snprintf(page, PAGE_SIZE, "%s\n", system_name);
+}
+
+static ssize_t system_name_store(struct kobject *kobj,
+				 struct kobj_attribute *attr,
+				 const char *buf,
+	size_t len)
+{
+	int rc;
+
+	rc = check_string("system_name", buf);
+	if (rc)
+		return rc;
+
+	set_string(system_name, buf);
+
+	return len;
+}
+
+static struct kobj_attribute system_name_attr =
+	__ATTR(system_name, 0644, system_name_show, system_name_store);
+
+static ssize_t sysplex_name_show(struct kobject *kobj,
+				 struct kobj_attribute *attr, char *page)
+{
+	return snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
+}
+
+static ssize_t sysplex_name_store(struct kobject *kobj,
+				  struct kobj_attribute *attr,
+				  const char *buf,
+	size_t len)
+{
+	int rc;
+
+	rc = check_string("sysplex_name", buf);
+	if (rc)
+		return rc;
+
+	set_string(sysplex_name, buf);
+
+	return len;
+}
+
+static struct kobj_attribute sysplex_name_attr =
+	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
+
+static ssize_t system_type_show(struct kobject *kobj,
+				struct kobj_attribute *attr, char *page)
+{
+	return snprintf(page, PAGE_SIZE, "%s\n", system_type);
+}
+
+static ssize_t system_type_store(struct kobject *kobj,
+				 struct kobj_attribute *attr,
+				 const char *buf,
+	size_t len)
+{
+	int rc;
+
+	rc = check_string("system_type", buf);
+	if (rc)
+		return rc;
+
+	set_string(system_type, buf);
+
+	return len;
+}
+
+static struct kobj_attribute system_type_attr =
+	__ATTR(system_type, 0644, system_type_show, system_type_store);
+
+static ssize_t system_level_show(struct kobject *kobj,
+				 struct kobj_attribute *attr, char *page)
+{
+	unsigned long long level = system_level;
+
+	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
+}
+
+static ssize_t system_level_store(struct kobject *kobj,
+				  struct kobj_attribute *attr,
+				  const char *buf,
+	size_t len)
+{
+	unsigned long long level;
+	char *endp;
+
+	level = simple_strtoull(buf, &endp, 16);
+
+	if (endp == buf)
+		return -EINVAL;
+	if (*endp == '\n')
+		endp++;
+	if (*endp)
+		return -EINVAL;
+
+	system_level = level;
+
+	return len;
+}
+
+static struct kobj_attribute system_level_attr =
+	__ATTR(system_level, 0644, system_level_show, system_level_store);
+
+static ssize_t set_store(struct kobject *kobj,
+			 struct kobj_attribute *attr,
+			 const char *buf, size_t len)
+{
+	int rc;
+
+	rc = cpi_req();
+	if (rc)
+		return rc;
+
+	return len;
+}
+
+static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
+
+static struct attribute *cpi_attrs[] = {
+	&system_name_attr.attr,
+	&sysplex_name_attr.attr,
+	&system_type_attr.attr,
+	&system_level_attr.attr,
+	&set_attr.attr,
+	NULL,
+};
+
+static struct attribute_group cpi_attr_group = {
+	.attrs = cpi_attrs,
+};
+
+static struct kset *cpi_kset;
+
+int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
+		      const u64 level)
+{
+	int rc;
+
+	rc = check_string("system_name", system);
+	if (rc)
+		return rc;
+	rc = check_string("sysplex_name", sysplex);
+	if (rc)
+		return rc;
+	rc = check_string("system_type", type);
+	if (rc)
+		return rc;
+
+	set_string(system_name, system);
+	set_string(sysplex_name, sysplex);
+	set_string(system_type, type);
+	system_level = level;
+
+	return cpi_req();
+}
+EXPORT_SYMBOL(sclp_cpi_set_data);
+
+static int __init cpi_init(void)
+{
+	int rc;
+
+	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
+	if (!cpi_kset)
+		return -ENOMEM;
+
+	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
+	if (rc)
+		kset_unregister(cpi_kset);
+
+	return rc;
+}
+
+__initcall(cpi_init);