[net-next-2.6.git] / drivers / s390 / char / monwriter.c

/*
 * drivers/s390/char/monwriter.c
 *
 * Character device driver for writing z/VM *MONITOR service records.
 *
 * Copyright (C) IBM Corp. 2006
 *
 * Author(s): Melissa Howland <Melissa.Howland@us.ibm.com>
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/ctype.h>
#include <linux/poll.h>
#include <asm/uaccess.h>
#include <asm/ebcdic.h>
#include <asm/io.h>
#include <asm/appldata.h>
#include <asm/monwriter.h>

#define MONWRITE_MAX_DATALEN	4010

static int mon_max_bufs = 255;
static int mon_buf_count;

struct mon_buf {
	struct list_head list;
	struct monwrite_hdr hdr;
	int diag_done;
	char *data;
};

struct mon_private {
	struct list_head list;
	struct monwrite_hdr hdr;
	size_t hdr_to_read;
	size_t data_to_read;
	struct mon_buf *current_buf;
};

/*
 * helper functions
 */

static int monwrite_diag(struct monwrite_hdr *myhdr, char *buffer, int fcn)
{
	struct appldata_product_id id;
	int rc;

	strcpy(id.prod_nr, "LNXAPPL");
	id.prod_fn = myhdr->applid;
	id.record_nr = myhdr->record_num;
	id.version_nr = myhdr->version;
	id.release_nr = myhdr->release;
	id.mod_lvl = myhdr->mod_level;
	rc = appldata_asm(&id, fcn, (void *) buffer, myhdr->datalen);
	if (rc <= 0)
		return rc;
	if (rc == 5)
		return -EPERM;
	printk("DIAG X'DC' error with return code: %i\n", rc);
	return -EINVAL;
}

static struct mon_buf *monwrite_find_hdr(struct mon_private *monpriv,
					 struct monwrite_hdr *monhdr)
{
	struct mon_buf *entry, *next;

	list_for_each_entry_safe(entry, next, &monpriv->list, list)
		if ((entry->hdr.mon_function == monhdr->mon_function ||
		     monhdr->mon_function == MONWRITE_STOP_INTERVAL) &&
		    entry->hdr.applid == monhdr->applid &&
		    entry->hdr.record_num == monhdr->record_num &&
		    entry->hdr.version == monhdr->version &&
		    entry->hdr.release == monhdr->release &&
		    entry->hdr.mod_level == monhdr->mod_level)
			return entry;

	return NULL;
}

static int monwrite_new_hdr(struct mon_private *monpriv)
{
	struct monwrite_hdr *monhdr = &monpriv->hdr;
	struct mon_buf *monbuf;
	int rc;

	if (monhdr->datalen > MONWRITE_MAX_DATALEN ||
	    monhdr->mon_function > MONWRITE_START_CONFIG ||
	    monhdr->hdrlen != sizeof(struct monwrite_hdr))
		return -EINVAL;
	monbuf = NULL;
	if (monhdr->mon_function != MONWRITE_GEN_EVENT)
		monbuf = monwrite_find_hdr(monpriv, monhdr);
	if (monbuf) {
		if (monhdr->mon_function == MONWRITE_STOP_INTERVAL) {
			monhdr->datalen = monbuf->hdr.datalen;
			rc = monwrite_diag(monhdr, monbuf->data,
					   APPLDATA_STOP_REC);
			list_del(&monbuf->list);
			mon_buf_count--;
			kfree(monbuf->data);
			kfree(monbuf);
			monbuf = NULL;
		}
	} else if (monhdr->mon_function != MONWRITE_STOP_INTERVAL) {
		if (mon_buf_count >= mon_max_bufs)
			return -ENOSPC;
		monbuf = kzalloc(sizeof(struct mon_buf), GFP_KERNEL);
		if (!monbuf)
			return -ENOMEM;
		monbuf->data = kzalloc(monhdr->datalen,
				       GFP_KERNEL | GFP_DMA);
		if (!monbuf->data) {
			kfree(monbuf);
			return -ENOMEM;
		}
		monbuf->hdr = *monhdr;
		list_add_tail(&monbuf->list, &monpriv->list);
		if (monhdr->mon_function != MONWRITE_GEN_EVENT)
			mon_buf_count++;
	}
	monpriv->current_buf = monbuf;
	return 0;
}

static int monwrite_new_data(struct mon_private *monpriv)
{
	struct monwrite_hdr *monhdr = &monpriv->hdr;
	struct mon_buf *monbuf = monpriv->current_buf;
	int rc = 0;

	switch (monhdr->mon_function) {
	case MONWRITE_START_INTERVAL:
		if (!monbuf->diag_done) {
			rc = monwrite_diag(monhdr, monbuf->data,
					   APPLDATA_START_INTERVAL_REC);
			monbuf->diag_done = 1;
		}
		break;
	case MONWRITE_START_CONFIG:
		if (!monbuf->diag_done) {
			rc = monwrite_diag(monhdr, monbuf->data,
					   APPLDATA_START_CONFIG_REC);
			monbuf->diag_done = 1;
		}
		break;
	case MONWRITE_GEN_EVENT:
		rc = monwrite_diag(monhdr, monbuf->data,
				   APPLDATA_GEN_EVENT_REC);
		list_del(&monpriv->current_buf->list);
		kfree(monpriv->current_buf->data);
		kfree(monpriv->current_buf);
		monpriv->current_buf = NULL;
		break;
	default:
		/* monhdr->mon_function is checked in monwrite_new_hdr */
		BUG();
	}
	return rc;
}

/*
 * file operations
 */

static int monwrite_open(struct inode *inode, struct file *filp)
{
	struct mon_private *monpriv;

	monpriv = kzalloc(sizeof(struct mon_private), GFP_KERNEL);
	if (!monpriv)
		return -ENOMEM;
	INIT_LIST_HEAD(&monpriv->list);
	monpriv->hdr_to_read = sizeof(monpriv->hdr);
	filp->private_data = monpriv;
	return nonseekable_open(inode, filp);
}

static int monwrite_close(struct inode *inode, struct file *filp)
{
	struct mon_private *monpriv = filp->private_data;
	struct mon_buf *entry, *next;

	list_for_each_entry_safe(entry, next, &monpriv->list, list) {
		if (entry->hdr.mon_function != MONWRITE_GEN_EVENT)
			monwrite_diag(&entry->hdr, entry->data,
				      APPLDATA_STOP_REC);
		mon_buf_count--;
		list_del(&entry->list);
		kfree(entry->data);
		kfree(entry);
	}
	kfree(monpriv);
	return 0;
}

static ssize_t monwrite_write(struct file *filp, const char __user *data,
			      size_t count, loff_t *ppos)
{
	struct mon_private *monpriv = filp->private_data;
	size_t len, written;
	void *to;
	int rc;

	for (written = 0; written < count; ) {
		if (monpriv->hdr_to_read) {
			len = min(count - written, monpriv->hdr_to_read);
			to = (char *) &monpriv->hdr +
				sizeof(monpriv->hdr) - monpriv->hdr_to_read;
			if (copy_from_user(to, data + written, len)) {
				rc = -EFAULT;
				goto out_error;
			}
			monpriv->hdr_to_read -= len;
			written += len;
			if (monpriv->hdr_to_read > 0)
				continue;
			rc = monwrite_new_hdr(monpriv);
			if (rc)
				goto out_error;
			monpriv->data_to_read = monpriv->current_buf ?
				monpriv->current_buf->hdr.datalen : 0;
		}

		if (monpriv->data_to_read) {
			len = min(count - written, monpriv->data_to_read);
			to = monpriv->current_buf->data +
				monpriv->hdr.datalen - monpriv->data_to_read;
			if (copy_from_user(to, data + written, len)) {
				rc = -EFAULT;
				goto out_error;
			}
			monpriv->data_to_read -= len;
			written += len;
			if (monpriv->data_to_read > 0)
				continue;
			rc = monwrite_new_data(monpriv);
			if (rc)
				goto out_error;
		}
		monpriv->hdr_to_read = sizeof(monpriv->hdr);
	}
	return written;

out_error:
	monpriv->data_to_read = 0;
	monpriv->hdr_to_read = sizeof(struct monwrite_hdr);
	return rc;
}

static const struct file_operations monwrite_fops = {
	.owner	 = THIS_MODULE,
	.open	 = &monwrite_open,
	.release = &monwrite_close,
	.write	 = &monwrite_write,
};

static struct miscdevice mon_dev = {
	.name	= "monwriter",
	.fops	= &monwrite_fops,
	.minor	= MISC_DYNAMIC_MINOR,
};

/*
 * module init/exit
 */

static int __init mon_init(void)
{
	if (MACHINE_IS_VM)
		return misc_register(&mon_dev);
	else
		return -ENODEV;
}

static void __exit mon_exit(void)
{
	WARN_ON(misc_deregister(&mon_dev) != 0);
}

module_init(mon_init);
module_exit(mon_exit);

module_param_named(max_bufs, mon_max_bufs, int, 0644);
MODULE_PARM_DESC(max_bufs, "Maximum number of sample monitor data buffers"
		 "that can be active at one time");

MODULE_AUTHOR("Melissa Howland <Melissa.Howland@us.ibm.com>");
MODULE_DESCRIPTION("Character device driver for writing z/VM "
		   "APPLDATA monitor records.");
MODULE_LICENSE("GPL");
Commit	Line	Data
31b58088 MH	1	/*
	2	* drivers/s390/char/monwriter.c
	3	*
	4	* Character device driver for writing z/VM *MONITOR service records.
	5	*
	6	* Copyright (C) IBM Corp. 2006
	7	*
	8	* Author(s): Melissa Howland <Melissa.Howland@us.ibm.com>
	9	*/
	10
	11	#include <linux/module.h>
	12	#include <linux/moduleparam.h>
	13	#include <linux/init.h>
	14	#include <linux/errno.h>
	15	#include <linux/types.h>
	16	#include <linux/kernel.h>
	17	#include <linux/miscdevice.h>
	18	#include <linux/ctype.h>
	19	#include <linux/poll.h>
	20	#include <asm/uaccess.h>
	21	#include <asm/ebcdic.h>
	22	#include <asm/io.h>
	23	#include <asm/appldata.h>
	24	#include <asm/monwriter.h>
	25
524a237e	26	#define MONWRITE_MAX_DATALEN 4010
31b58088 MH	27
31b58088 MH	28	static int mon_max_bufs = 255;
2d103d5a	29	static int mon_buf_count;
31b58088 MH	30
	31	struct mon_buf {
	32	struct list_head list;
	33	struct monwrite_hdr hdr;
	34	int diag_done;
	35	char *data;
	36	};
	37
	38	struct mon_private {
	39	struct list_head list;
	40	struct monwrite_hdr hdr;
	41	size_t hdr_to_read;
	42	size_t data_to_read;
	43	struct mon_buf *current_buf;
31b58088 MH	44	};
	45
	46	/*
	47	* helper functions
	48	*/
	49
	50	static int monwrite_diag(struct monwrite_hdr myhdr, char buffer, int fcn)
	51	{
	52	struct appldata_product_id id;
	53	int rc;
	54
	55	strcpy(id.prod_nr, "LNXAPPL");
	56	id.prod_fn = myhdr->applid;
	57	id.record_nr = myhdr->record_num;
	58	id.version_nr = myhdr->version;
	59	id.release_nr = myhdr->release;
	60	id.mod_lvl = myhdr->mod_level;
	61	rc = appldata_asm(&id, fcn, (void *) buffer, myhdr->datalen);
	62	if (rc <= 0)
	63	return rc;
	64	if (rc == 5)
	65	return -EPERM;
	66	printk("DIAG X'DC' error with return code: %i\n", rc);
	67	return -EINVAL;
	68	}
	69
4d284cac HC	70	static struct mon_buf monwrite_find_hdr(struct mon_private monpriv,
4d284cac HC	71	struct monwrite_hdr *monhdr)
31b58088 MH	72	{
	73	struct mon_buf entry, next;
	74
	75	list_for_each_entry_safe(entry, next, &monpriv->list, list)
2c91971f MH	76	if ((entry->hdr.mon_function == monhdr->mon_function \|\|
	77	monhdr->mon_function == MONWRITE_STOP_INTERVAL) &&
	78	entry->hdr.applid == monhdr->applid &&
31b58088 MH	79	entry->hdr.record_num == monhdr->record_num &&
	80	entry->hdr.version == monhdr->version &&
	81	entry->hdr.release == monhdr->release &&
	82	entry->hdr.mod_level == monhdr->mod_level)
	83	return entry;
2c91971f	84
31b58088 MH	85	return NULL;
	86	}
	87
	88	static int monwrite_new_hdr(struct mon_private *monpriv)
	89	{
	90	struct monwrite_hdr *monhdr = &monpriv->hdr;
	91	struct mon_buf *monbuf;
	92	int rc;
	93
	94	if (monhdr->datalen > MONWRITE_MAX_DATALEN \|\|
	95	monhdr->mon_function > MONWRITE_START_CONFIG \|\|
	96	monhdr->hdrlen != sizeof(struct monwrite_hdr))
	97	return -EINVAL;
2c91971f MH	98	monbuf = NULL;
	99	if (monhdr->mon_function != MONWRITE_GEN_EVENT)
	100	monbuf = monwrite_find_hdr(monpriv, monhdr);
31b58088 MH	101	if (monbuf) {
	102	if (monhdr->mon_function == MONWRITE_STOP_INTERVAL) {
	103	monhdr->datalen = monbuf->hdr.datalen;
	104	rc = monwrite_diag(monhdr, monbuf->data,
	105	APPLDATA_STOP_REC);
	106	list_del(&monbuf->list);
2d103d5a	107	mon_buf_count--;
31b58088 MH	108	kfree(monbuf->data);
	109	kfree(monbuf);
	110	monbuf = NULL;
	111	}
2c91971f	112	} else if (monhdr->mon_function != MONWRITE_STOP_INTERVAL) {
2d103d5a	113	if (mon_buf_count >= mon_max_bufs)
31b58088 MH	114	return -ENOSPC;
	115	monbuf = kzalloc(sizeof(struct mon_buf), GFP_KERNEL);
	116	if (!monbuf)
	117	return -ENOMEM;
715d854b	118	monbuf->data = kzalloc(monhdr->datalen,
31b58088 MH	119	GFP_KERNEL \| GFP_DMA);
	120	if (!monbuf->data) {
	121	kfree(monbuf);
	122	return -ENOMEM;
	123	}
	124	monbuf->hdr = *monhdr;
	125	list_add_tail(&monbuf->list, &monpriv->list);
2c91971f MH	126	if (monhdr->mon_function != MONWRITE_GEN_EVENT)
2c91971f MH	127	mon_buf_count++;
31b58088 MH	128	}
	129	monpriv->current_buf = monbuf;
	130	return 0;
	131	}
	132
	133	static int monwrite_new_data(struct mon_private *monpriv)
	134	{
	135	struct monwrite_hdr *monhdr = &monpriv->hdr;
	136	struct mon_buf *monbuf = monpriv->current_buf;
	137	int rc = 0;
	138
	139	switch (monhdr->mon_function) {
	140	case MONWRITE_START_INTERVAL:
	141	if (!monbuf->diag_done) {
	142	rc = monwrite_diag(monhdr, monbuf->data,
	143	APPLDATA_START_INTERVAL_REC);
	144	monbuf->diag_done = 1;
	145	}
	146	break;
	147	case MONWRITE_START_CONFIG:
	148	if (!monbuf->diag_done) {
	149	rc = monwrite_diag(monhdr, monbuf->data,
	150	APPLDATA_START_CONFIG_REC);
	151	monbuf->diag_done = 1;
	152	}
	153	break;
	154	case MONWRITE_GEN_EVENT:
	155	rc = monwrite_diag(monhdr, monbuf->data,
	156	APPLDATA_GEN_EVENT_REC);
	157	list_del(&monpriv->current_buf->list);
	158	kfree(monpriv->current_buf->data);
	159	kfree(monpriv->current_buf);
	160	monpriv->current_buf = NULL;
	161	break;
	162	default:
	163	/* monhdr->mon_function is checked in monwrite_new_hdr */
	164	BUG();
	165	}
	166	return rc;
	167	}
	168
	169	/*
	170	* file operations
	171	*/
	172
	173	static int monwrite_open(struct inode inode, struct file filp)
	174	{
	175	struct mon_private *monpriv;
	176
	177	monpriv = kzalloc(sizeof(struct mon_private), GFP_KERNEL);
	178	if (!monpriv)
	179	return -ENOMEM;
	180	INIT_LIST_HEAD(&monpriv->list);
	181	monpriv->hdr_to_read = sizeof(monpriv->hdr);
	182	filp->private_data = monpriv;
	183	return nonseekable_open(inode, filp);
	184	}
	185
	186	static int monwrite_close(struct inode inode, struct file filp)
	187	{
	188	struct mon_private *monpriv = filp->private_data;
	189	struct mon_buf entry, next;
	190
	191	list_for_each_entry_safe(entry, next, &monpriv->list, list) {
192	if (entry->hdr.mon_function != MONWRITE_GEN_EVENT)
193	monwrite_diag(&entry->hdr, entry->data,
194	APPLDATA_STOP_REC);
2d103d5a	195	mon_buf_count--;
31b58088 MH	196	list_del(&entry->list);
	197	kfree(entry->data);
	198	kfree(entry);
	199	}
	200	kfree(monpriv);
	201	return 0;
	202	}
	203
	204	static ssize_t monwrite_write(struct file filp, const char __user data,
	205	size_t count, loff_t *ppos)
	206	{
	207	struct mon_private *monpriv = filp->private_data;
	208	size_t len, written;
	209	void *to;
	210	int rc;
	211
	212	for (written = 0; written < count; ) {
	213	if (monpriv->hdr_to_read) {
	214	len = min(count - written, monpriv->hdr_to_read);
	215	to = (char *) &monpriv->hdr +
	216	sizeof(monpriv->hdr) - monpriv->hdr_to_read;
	217	if (copy_from_user(to, data + written, len)) {
	218	rc = -EFAULT;
	219	goto out_error;
	220	}
	221	monpriv->hdr_to_read -= len;
	222	written += len;
	223	if (monpriv->hdr_to_read > 0)
	224	continue;
	225	rc = monwrite_new_hdr(monpriv);
	226	if (rc)
	227	goto out_error;
	228	monpriv->data_to_read = monpriv->current_buf ?
	229	monpriv->current_buf->hdr.datalen : 0;
	230	}
	231
	232	if (monpriv->data_to_read) {
	233	len = min(count - written, monpriv->data_to_read);
	234	to = monpriv->current_buf->data +
	235	monpriv->hdr.datalen - monpriv->data_to_read;
	236	if (copy_from_user(to, data + written, len)) {
	237	rc = -EFAULT;
	238	goto out_error;
	239	}
	240	monpriv->data_to_read -= len;
	241	written += len;
	242	if (monpriv->data_to_read > 0)
	243	continue;
	244	rc = monwrite_new_data(monpriv);
	245	if (rc)
	246	goto out_error;
	247	}
	248	monpriv->hdr_to_read = sizeof(monpriv->hdr);
	249	}
	250	return written;
	251
	252	out_error:
	253	monpriv->data_to_read = 0;
	254	monpriv->hdr_to_read = sizeof(struct monwrite_hdr);
	255	return rc;
	256	}
	257
d54b1fdb	258	static const struct file_operations monwrite_fops = {
31b58088 MH	259	.owner = THIS_MODULE,
	260	.open = &monwrite_open,
	261	.release = &monwrite_close,
	262	.write = &monwrite_write,
	263	};
	264
	265	static struct miscdevice mon_dev = {
	266	.name = "monwriter",
	267	.fops = &monwrite_fops,
	268	.minor = MISC_DYNAMIC_MINOR,
	269	};
	270
	271	/*
	272	* module init/exit
	273	*/
	274
	275	static int __init mon_init(void)
	276	{
	277	if (MACHINE_IS_VM)
	278	return misc_register(&mon_dev);
	279	else
	280	return -ENODEV;
	281	}
	282
	283	static void __exit mon_exit(void)
	284	{
	285	WARN_ON(misc_deregister(&mon_dev) != 0);
	286	}
	287
	288	module_init(mon_init);
	289	module_exit(mon_exit);
	290
	291	module_param_named(max_bufs, mon_max_bufs, int, 0644);
	292	MODULE_PARM_DESC(max_bufs, "Maximum number of sample monitor data buffers"
	293	"that can be active at one time");
	294
	295	MODULE_AUTHOR("Melissa Howland <Melissa.Howland@us.ibm.com>");
	296	MODULE_DESCRIPTION("Character device driver for writing z/VM "
	297	"APPLDATA monitor records.");
	298	MODULE_LICENSE("GPL");