kernel-ark/drivers/s390/cio/blacklist.c
Jan Engelhardt 5c81cdbeff [S390] constify function pointer tables.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-01-26 14:11:32 +01:00

390 lines
9.0 KiB
C

/*
* drivers/s390/cio/blacklist.c
* S/390 common I/O routines -- blacklisting of specific devices
*
* Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
* Author(s): Ingo Adlung (adlung@de.ibm.com)
* Cornelia Huck (cornelia.huck@de.ibm.com)
* Arnd Bergmann (arndb@de.ibm.com)
*/
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.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 for each set 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[__MAX_SSID + 1][__BL_DEV_WORDS];
typedef enum {add, free} range_action;
/*
* Function: blacklist_range
* (Un-)blacklist the devices from-to
*/
static void
blacklist_range (range_action action, unsigned int from, unsigned int to,
unsigned int ssid)
{
if (!to)
to = from;
if (from > to || to > __MAX_SUBCHANNEL || ssid > __MAX_SSID) {
printk (KERN_WARNING "cio: Invalid blacklist range "
"0.%x.%04x to 0.%x.%04x, skipping\n",
ssid, from, ssid, to);
return;
}
for (; from <= to; from++) {
if (action == add)
set_bit (from, bl_dev[ssid]);
else
clear_bit (from, bl_dev[ssid]);
}
}
/*
* Function: blacklist_busid
* Get devno/busid from given string.
* Shamelessly grabbed from dasd_devmap.c.
*/
static int
blacklist_busid(char **str, int *id0, int *ssid, 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 = *ssid = 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;
*ssid = 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 "cio: Invalid cio_ignore parameter '%s'\n", sav);
return 1;
}
static int
blacklist_parse_parameters (char *str, range_action action)
{
int from, to, from_id0, to_id0, from_ssid, to_ssid;
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) {
int j;
str += 3;
for (j=0; j <= __MAX_SSID; j++)
blacklist_range(ra, 0, __MAX_SUBCHANNEL, j);
} else {
int rc;
rc = blacklist_busid(&str, &from_id0,
&from_ssid, &from);
if (rc)
continue;
to = from;
to_id0 = from_id0;
to_ssid = from_ssid;
if (*str == '-') {
str++;
rc = blacklist_busid(&str, &to_id0,
&to_ssid, &to);
if (rc)
continue;
}
if (*str == '-') {
printk(KERN_WARNING "cio: invalid cio_ignore "
"parameter '%s'\n",
strsep(&str, ",\n"));
continue;
}
if ((from_id0 != to_id0) ||
(from_ssid != to_ssid)) {
printk(KERN_WARNING "cio: invalid cio_ignore "
"range %x.%x.%04x-%x.%x.%04x\n",
from_id0, from_ssid, from,
to_id0, to_ssid, to);
continue;
}
blacklist_range (ra, from, to, to_ssid);
}
}
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 ssid, int devno)
{
return test_bit (devno, bl_dev[ssid]);
}
#ifdef CONFIG_PROC_FS
/*
* Function: blacklist_parse_proc_parameters
* parse the stuff which is piped to /proc/cio_ignore
*/
static 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: 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;
}
css_schedule_reprobe();
}
/* Iterator struct for all devices. */
struct ccwdev_iter {
int devno;
int ssid;
int in_range;
};
static void *
cio_ignore_proc_seq_start(struct seq_file *s, loff_t *offset)
{
struct ccwdev_iter *iter;
if (*offset >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1))
return NULL;
iter = kzalloc(sizeof(struct ccwdev_iter), GFP_KERNEL);
if (!iter)
return ERR_PTR(-ENOMEM);
iter->ssid = *offset / (__MAX_SUBCHANNEL + 1);
iter->devno = *offset % (__MAX_SUBCHANNEL + 1);
return iter;
}
static void
cio_ignore_proc_seq_stop(struct seq_file *s, void *it)
{
if (!IS_ERR(it))
kfree(it);
}
static void *
cio_ignore_proc_seq_next(struct seq_file *s, void *it, loff_t *offset)
{
struct ccwdev_iter *iter;
if (*offset >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1))
return NULL;
iter = it;
if (iter->devno == __MAX_SUBCHANNEL) {
iter->devno = 0;
iter->ssid++;
if (iter->ssid > __MAX_SSID)
return NULL;
} else
iter->devno++;
(*offset)++;
return iter;
}
static int
cio_ignore_proc_seq_show(struct seq_file *s, void *it)
{
struct ccwdev_iter *iter;
iter = it;
if (!is_blacklisted(iter->ssid, iter->devno))
/* Not blacklisted, nothing to output. */
return 0;
if (!iter->in_range) {
/* First device in range. */
if ((iter->devno == __MAX_SUBCHANNEL) ||
!is_blacklisted(iter->ssid, iter->devno + 1))
/* Singular device. */
return seq_printf(s, "0.%x.%04x\n",
iter->ssid, iter->devno);
iter->in_range = 1;
return seq_printf(s, "0.%x.%04x-", iter->ssid, iter->devno);
}
if ((iter->devno == __MAX_SUBCHANNEL) ||
!is_blacklisted(iter->ssid, iter->devno + 1)) {
/* Last device in range. */
iter->in_range = 0;
return seq_printf(s, "0.%x.%04x\n", iter->ssid, iter->devno);
}
return 0;
}
static ssize_t
cio_ignore_write(struct file *file, const char __user *user_buf,
size_t user_len, loff_t *offset)
{
char *buf;
if (*offset)
return -EINVAL;
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 const struct seq_operations cio_ignore_proc_seq_ops = {
.start = cio_ignore_proc_seq_start,
.stop = cio_ignore_proc_seq_stop,
.next = cio_ignore_proc_seq_next,
.show = cio_ignore_proc_seq_show,
};
static int
cio_ignore_proc_open(struct inode *inode, struct file *file)
{
return seq_open(file, &cio_ignore_proc_seq_ops);
}
static const struct file_operations cio_ignore_proc_fops = {
.open = cio_ignore_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
.write = cio_ignore_write,
};
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 -ENOENT;
entry->proc_fops = &cio_ignore_proc_fops;
return 0;
}
__initcall (cio_ignore_proc_init);
#endif /* CONFIG_PROC_FS */