[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / s390 / cio / blacklist.c

/*
 *  drivers/s390/cio/blacklist.c
 *   S/390 common I/O routines -- blacklisting of specific devices
 *   $Revision: 1.35 $
 *
 *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
 *			      IBM Corporation
 *    Author(s): Ingo Adlung (adlung@de.ibm.com)
 *		 Cornelia Huck (cohuck@de.ibm.com)
 *		 Arnd Bergmann (arndb@de.ibm.com)
 */

#include <linux/config.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
#include <linux/ctype.h>
#include <linux/device.h>

#include <asm/cio.h>
#include <asm/uaccess.h>

#include "blacklist.h"
#include "cio.h"
#include "cio_debug.h"
#include "css.h"

/*
 * "Blacklisting" of certain devices:
 * Device numbers given in the commandline as cio_ignore=... won't be known
 * to Linux.
 *
 * These can be single devices or ranges of devices
 */

/* 65536 bits to indicate if a devno is blacklisted or not */
#define __BL_DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
			 (8*sizeof(long)))
static unsigned long bl_dev[__BL_DEV_WORDS];
typedef enum {add, free} range_action;

/*
 * Function: blacklist_range
 * (Un-)blacklist the devices from-to
 */
static inline void
blacklist_range (range_action action, unsigned int from, unsigned int to)
{
	if (!to)
		to = from;

	if (from > to || to > __MAX_SUBCHANNEL) {
		printk (KERN_WARNING "Invalid blacklist range "
			"0x%04x to 0x%04x, skipping\n", from, to);
		return;
	}
	for (; from <= to; from++) {
		if (action == add)
			set_bit (from, bl_dev);
		else
			clear_bit (from, bl_dev);
	}
}

/*
 * Function: blacklist_busid
 * Get devno/busid from given string.
 * Shamelessly grabbed from dasd_devmap.c.
 */
static inline int
blacklist_busid(char **str, int *id0, int *id1, int *devno)
{
	int val, old_style;
	char *sav;

	sav = *str;

	/* check for leading '0x' */
	old_style = 0;
	if ((*str)[0] == '0' && (*str)[1] == 'x') {
		*str += 2;
		old_style = 1;
	}
	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
		goto confused;
	val = simple_strtoul(*str, str, 16);
	if (old_style || (*str)[0] != '.') {
		*id0 = *id1 = 0;
		if (val < 0 || val > 0xffff)
			goto confused;
		*devno = val;
		if ((*str)[0] != ',' && (*str)[0] != '-' &&
		    (*str)[0] != '\n' && (*str)[0] != '\0')
			goto confused;
		return 0;
	}
	/* New style x.y.z busid */
	if (val < 0 || val > 0xff)
		goto confused;
	*id0 = val;
	(*str)++;
	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
		goto confused;
	val = simple_strtoul(*str, str, 16);
	if (val < 0 || val > 0xff || (*str)++[0] != '.')
		goto confused;
	*id1 = val;
	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
		goto confused;
	val = simple_strtoul(*str, str, 16);
	if (val < 0 || val > 0xffff)
		goto confused;
	*devno = val;
	if ((*str)[0] != ',' && (*str)[0] != '-' &&
	    (*str)[0] != '\n' && (*str)[0] != '\0')
		goto confused;
	return 0;
confused:
	strsep(str, ",\n");
	printk(KERN_WARNING "Invalid cio_ignore parameter '%s'\n", sav);
	return 1;
}

static inline int
blacklist_parse_parameters (char *str, range_action action)
{
	unsigned int from, to, from_id0, to_id0, from_id1, to_id1;

	while (*str != 0 && *str != '\n') {
		range_action ra = action;
		while(*str == ',')
			str++;
		if (*str == '!') {
			ra = !action;
			++str;
		}

		/*
		 * Since we have to parse the proc commands and the
		 * kernel arguments we have to check four cases
		 */
		if (strncmp(str,"all,",4) == 0 || strcmp(str,"all") == 0 ||
		    strncmp(str,"all\n",4) == 0 || strncmp(str,"all ",4) == 0) {
			from = 0;
			to = __MAX_SUBCHANNEL;
			str += 3;
		} else {
			int rc;

			rc = blacklist_busid(&str, &from_id0,
					     &from_id1, &from);
			if (rc)
				continue;
			to = from;
			to_id0 = from_id0;
			to_id1 = from_id1;
			if (*str == '-') {
				str++;
				rc = blacklist_busid(&str, &to_id0,
						     &to_id1, &to);
				if (rc)
					continue;
			}
			if (*str == '-') {
				printk(KERN_WARNING "invalid cio_ignore "
					"parameter '%s'\n",
					strsep(&str, ",\n"));
				continue;
			}
			if ((from_id0 != to_id0) || (from_id1 != to_id1)) {
				printk(KERN_WARNING "invalid cio_ignore range "
					"%x.%x.%04x-%x.%x.%04x\n",
					from_id0, from_id1, from,
					to_id0, to_id1, to);
				continue;
			}
		}
		/* FIXME: ignoring id0 and id1 here. */
		pr_debug("blacklist_setup: adding range "
			 "from 0.0.%04x to 0.0.%04x\n", from, to);
		blacklist_range (ra, from, to);
	}
	return 1;
}

/* Parsing the commandline for blacklist parameters, e.g. to blacklist
 * bus ids 0.0.1234, 0.0.1235 and 0.0.1236, you could use any of:
 * - cio_ignore=1234-1236
 * - cio_ignore=0x1234-0x1235,1236
 * - cio_ignore=0x1234,1235-1236
 * - cio_ignore=1236 cio_ignore=1234-0x1236
 * - cio_ignore=1234 cio_ignore=1236 cio_ignore=0x1235
 * - cio_ignore=0.0.1234-0.0.1236
 * - cio_ignore=0.0.1234,0x1235,1236
 * - ...
 */
static int __init
blacklist_setup (char *str)
{
	CIO_MSG_EVENT(6, "Reading blacklist parameters\n");
	return blacklist_parse_parameters (str, add);
}

__setup ("cio_ignore=", blacklist_setup);

/* Checking if devices are blacklisted */

/*
 * Function: is_blacklisted
 * Returns 1 if the given devicenumber can be found in the blacklist,
 * otherwise 0.
 * Used by validate_subchannel()
 */
int
is_blacklisted (int devno)
{
	return test_bit (devno, bl_dev);
}

#ifdef CONFIG_PROC_FS
static int
__s390_redo_validation(struct subchannel_id schid, void *data)
{
	int ret;
	struct subchannel *sch;

	sch = get_subchannel_by_schid(schid);
	if (sch) {
		/* Already known. */
		put_device(&sch->dev);
		return 0;
	}
	ret = css_probe_device(schid);
	if (ret == -ENXIO)
		return ret; /* We're through. */
	if (ret == -ENOMEM)
		/* Stop validation for now. Bad, but no need for a panic. */
		return ret;
	return 0;
}

/*
 * Function: s390_redo_validation
 * Look for no longer blacklisted devices
 * FIXME: there must be a better way to do this */
static inline void
s390_redo_validation (void)
{
	CIO_TRACE_EVENT (0, "redoval");

	for_each_subchannel(__s390_redo_validation, NULL);
}

/*
 * Function: blacklist_parse_proc_parameters
 * parse the stuff which is piped to /proc/cio_ignore
 */
static inline void
blacklist_parse_proc_parameters (char *buf)
{
	if (strncmp (buf, "free ", 5) == 0) {
		blacklist_parse_parameters (buf + 5, free);
	} else if (strncmp (buf, "add ", 4) == 0) {
		/* 
		 * We don't need to check for known devices since
		 * css_probe_device will handle this correctly. 
		 */
		blacklist_parse_parameters (buf + 4, add);
	} else {
		printk (KERN_WARNING "cio_ignore: Parse error; \n"
			KERN_WARNING "try using 'free all|<devno-range>,"
				     "<devno-range>,...'\n"
			KERN_WARNING "or 'add <devno-range>,"
				     "<devno-range>,...'\n");
		return;
	}

	s390_redo_validation ();
}

/* FIXME: These should be real bus ids and not home-grown ones! */
static int cio_ignore_read (char *page, char **start, off_t off,
			    int count, int *eof, void *data)
{
	const unsigned int entry_size = 18; /* "0.0.ABCD-0.0.EFGH\n" */
	long devno;
	int len;

	len = 0;
	for (devno = off; /* abuse the page variable
			   * as counter, see fs/proc/generic.c */
	     devno < __MAX_SUBCHANNEL && len + entry_size < count; devno++) {
		if (!test_bit(devno, bl_dev))
			continue;
		len += sprintf(page + len, "0.0.%04lx", devno);
		if (test_bit(devno + 1, bl_dev)) { /* print range */
			while (++devno < __MAX_SUBCHANNEL)
				if (!test_bit(devno, bl_dev))
					break;
			len += sprintf(page + len, "-0.0.%04lx", --devno);
		}
		len += sprintf(page + len, "\n");
	}

	if (devno < __MAX_SUBCHANNEL)
		*eof = 1;
	*start = (char *) (devno - off); /* number of checked entries */
	return len;
}

static int cio_ignore_write(struct file *file, const char __user *user_buf,
			     unsigned long user_len, void *data)
{
	char *buf;

	if (user_len > 65536)
		user_len = 65536;
	buf = vmalloc (user_len + 1); /* maybe better use the stack? */
	if (buf == NULL)
		return -ENOMEM;
	if (strncpy_from_user (buf, user_buf, user_len) < 0) {
		vfree (buf);
		return -EFAULT;
	}
	buf[user_len] = '\0';

	blacklist_parse_proc_parameters (buf);

	vfree (buf);
	return user_len;
}

static int
cio_ignore_proc_init (void)
{
	struct proc_dir_entry *entry;

	entry = create_proc_entry ("cio_ignore", S_IFREG | S_IRUGO | S_IWUSR,
				   &proc_root);
	if (!entry)
		return 0;

	entry->read_proc  = cio_ignore_read;
	entry->write_proc = cio_ignore_write;

	return 1;
}

__initcall (cio_ignore_proc_init);

#endif /* CONFIG_PROC_FS */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* drivers/s390/cio/blacklist.c
	3	* S/390 common I/O routines -- blacklisting of specific devices
d176795b	4	* $Revision: 1.35 $
1da177e4 LT	5	*
	6	* Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
	7	* IBM Corporation
	8	* Author(s): Ingo Adlung (adlung@de.ibm.com)
	9	* Cornelia Huck (cohuck@de.ibm.com)
	10	* Arnd Bergmann (arndb@de.ibm.com)
	11	*/
	12
	13	#include <linux/config.h>
	14	#include <linux/init.h>
	15	#include <linux/vmalloc.h>
	16	#include <linux/slab.h>
	17	#include <linux/proc_fs.h>
	18	#include <linux/ctype.h>
	19	#include <linux/device.h>
	20
	21	#include <asm/cio.h>
	22	#include <asm/uaccess.h>
	23
	24	#include "blacklist.h"
	25	#include "cio.h"
	26	#include "cio_debug.h"
	27	#include "css.h"
	28
	29	/*
	30	* "Blacklisting" of certain devices:
	31	* Device numbers given in the commandline as cio_ignore=... won't be known
	32	* to Linux.
	33	*
	34	* These can be single devices or ranges of devices
	35	*/
	36
	37	/* 65536 bits to indicate if a devno is blacklisted or not */
a8237fc4	38	#define __BL_DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1da177e4 LT	39	(8*sizeof(long)))
	40	static unsigned long bl_dev[__BL_DEV_WORDS];
	41	typedef enum {add, free} range_action;
	42
	43	/*
	44	* Function: blacklist_range
	45	* (Un-)blacklist the devices from-to
	46	*/
	47	static inline void
	48	blacklist_range (range_action action, unsigned int from, unsigned int to)
	49	{
	50	if (!to)
	51	to = from;
	52
a8237fc4	53	if (from > to \|\| to > __MAX_SUBCHANNEL) {
1da177e4 LT	54	printk (KERN_WARNING "Invalid blacklist range "
	55	"0x%04x to 0x%04x, skipping\n", from, to);
	56	return;
	57	}
	58	for (; from <= to; from++) {
	59	if (action == add)
	60	set_bit (from, bl_dev);
	61	else
	62	clear_bit (from, bl_dev);
	63	}
	64	}
	65
	66	/*
	67	* Function: blacklist_busid
	68	* Get devno/busid from given string.
	69	* Shamelessly grabbed from dasd_devmap.c.
	70	*/
	71	static inline int
	72	blacklist_busid(char *str, int id0, int id1, int devno)
	73	{
	74	int val, old_style;
	75	char *sav;
	76
	77	sav = *str;
	78
	79	/* check for leading '0x' */
	80	old_style = 0;
	81	if ((str)[0] == '0' && (str)[1] == 'x') {
	82	*str += 2;
	83	old_style = 1;
	84	}
	85	if (!isxdigit((str)[0])) / We require at least one hex digit */
	86	goto confused;
	87	val = simple_strtoul(*str, str, 16);
	88	if (old_style \|\| (*str)[0] != '.') {
	89	id0 = id1 = 0;
	90	if (val < 0 \|\| val > 0xffff)
	91	goto confused;
	92	*devno = val;
	93	if ((str)[0] != ',' && (str)[0] != '-' &&
	94	(str)[0] != '\n' && (str)[0] != '\0')
	95	goto confused;
	96	return 0;
	97	}
	98	/* New style x.y.z busid */
	99	if (val < 0 \|\| val > 0xff)
	100	goto confused;
	101	*id0 = val;
	102	(*str)++;
	103	if (!isxdigit((str)[0])) / We require at least one hex digit */
	104	goto confused;
	105	val = simple_strtoul(*str, str, 16);
	106	if (val < 0 \|\| val > 0xff \|\| (*str)++[0] != '.')
	107	goto confused;
	108	*id1 = val;
	109	if (!isxdigit((str)[0])) / We require at least one hex digit */
	110	goto confused;
	111	val = simple_strtoul(*str, str, 16);
	112	if (val < 0 \|\| val > 0xffff)
	113	goto confused;
	114	*devno = val;
	115	if ((str)[0] != ',' && (str)[0] != '-' &&
	116	(str)[0] != '\n' && (str)[0] != '\0')
	117	goto confused;
118	return 0;
119	confused:
120	strsep(str, ",\n");
121	printk(KERN_WARNING "Invalid cio_ignore parameter '%s'\n", sav);
122	return 1;
123	}
124
125	static inline int
126	blacklist_parse_parameters (char *str, range_action action)
127	{
128	unsigned int from, to, from_id0, to_id0, from_id1, to_id1;
129
130	while (str != 0 && str != '\n') {
131	range_action ra = action;
132	while(*str == ',')
133	str++;
134	if (*str == '!') {
135	ra = !action;
136	++str;
137	}
138
139	/*
140	* Since we have to parse the proc commands and the
141	* kernel arguments we have to check four cases
142	*/
143	if (strncmp(str,"all,",4) == 0 \|\| strcmp(str,"all") == 0 \|\|
144	strncmp(str,"all\n",4) == 0 \|\| strncmp(str,"all ",4) == 0) {
145	from = 0;
a8237fc4	146	to = __MAX_SUBCHANNEL;
1da177e4 LT	147	str += 3;
	148	} else {
	149	int rc;
	150
	151	rc = blacklist_busid(&str, &from_id0,
	152	&from_id1, &from);
	153	if (rc)
	154	continue;
	155	to = from;
	156	to_id0 = from_id0;
	157	to_id1 = from_id1;
	158	if (*str == '-') {
	159	str++;
	160	rc = blacklist_busid(&str, &to_id0,
	161	&to_id1, &to);
	162	if (rc)
	163	continue;
	164	}
	165	if (*str == '-') {
	166	printk(KERN_WARNING "invalid cio_ignore "
	167	"parameter '%s'\n",
	168	strsep(&str, ",\n"));
	169	continue;
	170	}
	171	if ((from_id0 != to_id0) \|\| (from_id1 != to_id1)) {
	172	printk(KERN_WARNING "invalid cio_ignore range "
	173	"%x.%x.%04x-%x.%x.%04x\n",
	174	from_id0, from_id1, from,
	175	to_id0, to_id1, to);
	176	continue;
	177	}
	178	}
	179	/* FIXME: ignoring id0 and id1 here. */
	180	pr_debug("blacklist_setup: adding range "
	181	"from 0.0.%04x to 0.0.%04x\n", from, to);
	182	blacklist_range (ra, from, to);
	183	}
	184	return 1;
	185	}
	186
	187	/* Parsing the commandline for blacklist parameters, e.g. to blacklist
	188	* bus ids 0.0.1234, 0.0.1235 and 0.0.1236, you could use any of:
	189	* - cio_ignore=1234-1236
	190	* - cio_ignore=0x1234-0x1235,1236
	191	* - cio_ignore=0x1234,1235-1236
	192	* - cio_ignore=1236 cio_ignore=1234-0x1236
	193	* - cio_ignore=1234 cio_ignore=1236 cio_ignore=0x1235
	194	* - cio_ignore=0.0.1234-0.0.1236
	195	* - cio_ignore=0.0.1234,0x1235,1236
	196	* - ...
	197	*/
	198	static int __init
	199	blacklist_setup (char *str)
	200	{
	201	CIO_MSG_EVENT(6, "Reading blacklist parameters\n");
	202	return blacklist_parse_parameters (str, add);
	203	}
	204
	205	__setup ("cio_ignore=", blacklist_setup);
	206
	207	/* Checking if devices are blacklisted */
	208
	209	/*
	210	* Function: is_blacklisted
211	* Returns 1 if the given devicenumber can be found in the blacklist,
212	* otherwise 0.
213	* Used by validate_subchannel()
214	*/
215	int
216	is_blacklisted (int devno)
217	{
218	return test_bit (devno, bl_dev);
219	}
220
221	#ifdef CONFIG_PROC_FS
f97a56fb CH	222	static int
	223	__s390_redo_validation(struct subchannel_id schid, void *data)
	224	{
	225	int ret;
	226	struct subchannel *sch;
	227
	228	sch = get_subchannel_by_schid(schid);
	229	if (sch) {
	230	/* Already known. */
	231	put_device(&sch->dev);
	232	return 0;
	233	}
	234	ret = css_probe_device(schid);
	235	if (ret == -ENXIO)
	236	return ret; /* We're through. */
	237	if (ret == -ENOMEM)
	238	/* Stop validation for now. Bad, but no need for a panic. */
	239	return ret;
	240	return 0;
	241	}
	242
1da177e4 LT	243	/*
	244	* Function: s390_redo_validation
	245	* Look for no longer blacklisted devices
	246	* FIXME: there must be a better way to do this */
	247	static inline void
	248	s390_redo_validation (void)
	249	{
1da177e4	250	CIO_TRACE_EVENT (0, "redoval");
1da177e4	251
f97a56fb	252	for_each_subchannel(__s390_redo_validation, NULL);
1da177e4 LT	253	}
	254
	255	/*
	256	* Function: blacklist_parse_proc_parameters
	257	* parse the stuff which is piped to /proc/cio_ignore
	258	*/
	259	static inline void
	260	blacklist_parse_proc_parameters (char *buf)
	261	{
	262	if (strncmp (buf, "free ", 5) == 0) {
	263	blacklist_parse_parameters (buf + 5, free);
	264	} else if (strncmp (buf, "add ", 4) == 0) {
	265	/*
	266	* We don't need to check for known devices since
	267	* css_probe_device will handle this correctly.
	268	*/
	269	blacklist_parse_parameters (buf + 4, add);
	270	} else {
	271	printk (KERN_WARNING "cio_ignore: Parse error; \n"
	272	KERN_WARNING "try using 'free all\|<devno-range>,"
	273	"<devno-range>,...'\n"
	274	KERN_WARNING "or 'add <devno-range>,"
	275	"<devno-range>,...'\n");
	276	return;
	277	}
	278
	279	s390_redo_validation ();
	280	}
	281
	282	/* FIXME: These should be real bus ids and not home-grown ones! */
	283	static int cio_ignore_read (char page, char *start, off_t off,
	284	int count, int eof, void data)
	285	{
	286	const unsigned int entry_size = 18; /* "0.0.ABCD-0.0.EFGH\n" */
	287	long devno;
	288	int len;
	289
	290	len = 0;
	291	for (devno = off; /* abuse the page variable
	292	* as counter, see fs/proc/generic.c */
a8237fc4	293	devno < __MAX_SUBCHANNEL && len + entry_size < count; devno++) {
1da177e4 LT	294	if (!test_bit(devno, bl_dev))
	295	continue;
	296	len += sprintf(page + len, "0.0.%04lx", devno);
	297	if (test_bit(devno + 1, bl_dev)) { /* print range */
a8237fc4	298	while (++devno < __MAX_SUBCHANNEL)
1da177e4 LT	299	if (!test_bit(devno, bl_dev))
	300	break;
	301	len += sprintf(page + len, "-0.0.%04lx", --devno);
	302	}
	303	len += sprintf(page + len, "\n");
	304	}
	305
a8237fc4	306	if (devno < __MAX_SUBCHANNEL)
1da177e4 LT	307	*eof = 1;
	308	start = (char ) (devno - off); /* number of checked entries */
	309	return len;
	310	}
	311
	312	static int cio_ignore_write(struct file file, const char __user user_buf,
	313	unsigned long user_len, void *data)
	314	{
	315	char *buf;
	316
	317	if (user_len > 65536)
	318	user_len = 65536;
	319	buf = vmalloc (user_len + 1); /* maybe better use the stack? */
	320	if (buf == NULL)
	321	return -ENOMEM;
	322	if (strncpy_from_user (buf, user_buf, user_len) < 0) {
	323	vfree (buf);
	324	return -EFAULT;
	325	}
	326	buf[user_len] = '\0';
	327
	328	blacklist_parse_proc_parameters (buf);
	329
	330	vfree (buf);
	331	return user_len;
	332	}
	333
	334	static int
	335	cio_ignore_proc_init (void)
	336	{
	337	struct proc_dir_entry *entry;
	338
	339	entry = create_proc_entry ("cio_ignore", S_IFREG \| S_IRUGO \| S_IWUSR,
	340	&proc_root);
	341	if (!entry)
	342	return 0;
	343
	344	entry->read_proc = cio_ignore_read;
	345	entry->write_proc = cio_ignore_write;
	346
	347	return 1;
	348	}
	349
	350	__initcall (cio_ignore_proc_init);
	351
	352	#endif /* CONFIG_PROC_FS */