path: root/drivers/s390/block/dasd_devmap.c

/*
 * File...........: linux/drivers/s390/block/dasd_devmap.c
 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
 *		    Horst Hummel <Horst.Hummel@de.ibm.com>
 *		    Carsten Otte <Cotte@de.ibm.com>
 *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
 * Bugreports.to..: <Linux390@de.ibm.com>
 * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
 *
 * Device mapping and dasd= parameter parsing functions. All devmap
 * functions may not be called from interrupt context. In particular
 * dasd_get_device is a no-no from interrupt context.
 *
 */

#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/module.h>

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

/* This is ugly... */
#define PRINTK_HEADER "dasd_devmap:"

#include "dasd_int.h"

kmem_cache_t *dasd_page_cache;
EXPORT_SYMBOL_GPL(dasd_page_cache);

/*
 * dasd_devmap_t is used to store the features and the relation
 * between device number and device index. To find a dasd_devmap_t
 * that corresponds to a device number of a device index each
 * dasd_devmap_t is added to two linked lists, one to search by
 * the device number and one to search by the device index. As
 * soon as big minor numbers are available the device index list
 * can be removed since the device number will then be identical
 * to the device index.
 */
struct dasd_devmap {
	struct list_head list;
	char bus_id[BUS_ID_SIZE];
        unsigned int devindex;
        unsigned short features;
	struct dasd_device *device;
	struct dasd_uid uid;
};

/*
 * dasd_servermap is used to store the server_id of all storage servers
 * accessed by DASD device driver.
 */
struct dasd_servermap {
	struct list_head list;
	struct server_id {
		char vendor[4];
		char serial[15];
	} sid;
};

static struct list_head dasd_serverlist;

/*
 * Parameter parsing functions for dasd= parameter. The syntax is:
 *   <devno>		: (0x)?[0-9a-fA-F]+
 *   <busid>		: [0-0a-f]\.[0-9a-f]\.(0x)?[0-9a-fA-F]+
 *   <feature>		: ro
 *   <feature_list>	: \(<feature>(:<feature>)*\)
 *   <devno-range>	: <devno>(-<devno>)?<feature_list>?
 *   <busid-range>	: <busid>(-<busid>)?<feature_list>?
 *   <devices>		: <devno-range>|<busid-range>
 *   <dasd_module>	: dasd_diag_mod|dasd_eckd_mod|dasd_fba_mod
 *
 *   <dasd>		: autodetect|probeonly|<devices>(,<devices>)*
 */

int dasd_probeonly =  0;	/* is true, when probeonly mode is active */
int dasd_autodetect = 0;	/* is true, when autodetection is active */
int dasd_nopav = 0;		/* is true, when PAV is disabled */
EXPORT_SYMBOL_GPL(dasd_nopav);

/*
 * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
 * it is named 'dasd' to directly be filled by insmod with the comma separated
 * strings when running as a module.
 */
static char *dasd[256];
module_param_array(dasd, charp, NULL, 0);

/*
 * Single spinlock to protect devmap and servermap structures and lists.
 */
static DEFINE_SPINLOCK(dasd_devmap_lock);

/*
 * Hash lists for devmap structures.
 */
static struct list_head dasd_hashlists[256];
int dasd_max_devindex;

static struct dasd_devmap *dasd_add_busid(char *, int);

static inline int
dasd_hash_busid(char *bus_id)
{
	int hash, i;

	hash = 0;
	for (i = 0; (i < BUS_ID_SIZE) && *bus_id; i++, bus_id++)
		hash += *bus_id;
	return hash & 0xff;
}

#ifndef MODULE
/*
 * The parameter parsing functions for builtin-drivers are called
 * before kmalloc works. Store the pointers to the parameters strings
 * into dasd[] for later processing.
 */
static int __init
dasd_call_setup(char *str)
{
	static int count = 0;

	if (count < 256)
		dasd[count++] = str;
	return 1;
}

__setup ("dasd=", dasd_call_setup);
#endif	/* #ifndef MODULE */

/*
 * Read a device busid/devno from a string.
 */
static inline int
dasd_busid(char **str, int *id0, int *id1, int *devno)
{
	int val, old_style;

	/* 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 */
		return -EINVAL;
	val = simple_strtoul(*str, str, 16);
	if (old_style || (*str)[0] != '.') {
		*id0 = *id1 = 0;
		if (val < 0 || val > 0xffff)
			return -EINVAL;
		*devno = val;
		return 0;
	}
	/* New style x.y.z busid */
	if (val < 0 || val > 0xff)
		return -EINVAL;
	*id0 = val;
	(*str)++;
	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
		return -EINVAL;
	val = simple_strtoul(*str, str, 16);
	if (val < 0 || val > 0xff || (*str)++[0] != '.')
		return -EINVAL;
	*id1 = val;
	if (!isxdigit((*str)[0]))	/* We require at least one hex digit */
		return -EINVAL;
	val = simple_strtoul(*str, str, 16);
	if (val