linux_dsm_epyc7002/drivers/s390/block/dasd_proc.c
Stefan Weinhuber e4258d55bf [S390] dasd: use vmalloc for statistics input buffer
The size of the buffer that is used to store DASD statistics input
strings depends on the user input. If the input string is to large,
the write operation could fail with -ENOMEM. To avoid this, use
vmalloc instead of kmalloc.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2011-08-03 16:44:19 +02:00

378 lines
9.7 KiB
C

/*
* File...........: linux/drivers/s390/block/dasd_proc.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, 1999-2002
*
* /proc interface for the dasd driver.
*
*/
#define KMSG_COMPONENT "dasd"
#include <linux/ctype.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/seq_file.h>
#include <linux/vmalloc.h>
#include <linux/proc_fs.h>
#include <asm/debug.h>
#include <asm/uaccess.h>
/* This is ugly... */
#define PRINTK_HEADER "dasd_proc:"
#include "dasd_int.h"
static struct proc_dir_entry *dasd_proc_root_entry = NULL;
static struct proc_dir_entry *dasd_devices_entry = NULL;
static struct proc_dir_entry *dasd_statistics_entry = NULL;
static int
dasd_devices_show(struct seq_file *m, void *v)
{
struct dasd_device *device;
struct dasd_block *block;
char *substr;
device = dasd_device_from_devindex((unsigned long) v - 1);
if (IS_ERR(device))
return 0;
if (device->block)
block = device->block;
else {
dasd_put_device(device);
return 0;
}
/* Print device number. */
seq_printf(m, "%s", dev_name(&device->cdev->dev));
/* Print discipline string. */
if (device->discipline != NULL)
seq_printf(m, "(%s)", device->discipline->name);
else
seq_printf(m, "(none)");
/* Print kdev. */
if (block->gdp)
seq_printf(m, " at (%3d:%6d)",
MAJOR(disk_devt(block->gdp)),
MINOR(disk_devt(block->gdp)));
else
seq_printf(m, " at (???:??????)");
/* Print device name. */
if (block->gdp)
seq_printf(m, " is %-8s", block->gdp->disk_name);
else
seq_printf(m, " is ????????");
/* Print devices features. */
substr = (device->features & DASD_FEATURE_READONLY) ? "(ro)" : " ";
seq_printf(m, "%4s: ", substr);
/* Print device status information. */
switch (device->state) {
case DASD_STATE_NEW:
seq_printf(m, "new");
break;
case DASD_STATE_KNOWN:
seq_printf(m, "detected");
break;
case DASD_STATE_BASIC:
seq_printf(m, "basic");
break;
case DASD_STATE_UNFMT:
seq_printf(m, "unformatted");
break;
case DASD_STATE_READY:
case DASD_STATE_ONLINE:
seq_printf(m, "active ");
if (dasd_check_blocksize(block->bp_block))
seq_printf(m, "n/f ");
else
seq_printf(m,
"at blocksize: %d, %lld blocks, %lld MB",
block->bp_block, block->blocks,
((block->bp_block >> 9) *
block->blocks) >> 11);
break;
default:
seq_printf(m, "no stat");
break;
}
dasd_put_device(device);
if (dasd_probeonly)
seq_printf(m, "(probeonly)");
seq_printf(m, "\n");
return 0;
}
static void *dasd_devices_start(struct seq_file *m, loff_t *pos)
{
if (*pos >= dasd_max_devindex)
return NULL;
return (void *)((unsigned long) *pos + 1);
}
static void *dasd_devices_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return dasd_devices_start(m, pos);
}
static void dasd_devices_stop(struct seq_file *m, void *v)
{
}
static const struct seq_operations dasd_devices_seq_ops = {
.start = dasd_devices_start,
.next = dasd_devices_next,
.stop = dasd_devices_stop,
.show = dasd_devices_show,
};
static int dasd_devices_open(struct inode *inode, struct file *file)
{
return seq_open(file, &dasd_devices_seq_ops);
}
static const struct file_operations dasd_devices_file_ops = {
.owner = THIS_MODULE,
.open = dasd_devices_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#ifdef CONFIG_DASD_PROFILE
static int dasd_stats_all_block_on(void)
{
int i, rc;
struct dasd_device *device;
rc = 0;
for (i = 0; i < dasd_max_devindex; ++i) {
device = dasd_device_from_devindex(i);
if (IS_ERR(device))
continue;
if (device->block)
rc = dasd_profile_on(&device->block->profile);
dasd_put_device(device);
if (rc)
return rc;
}
return 0;
}
static void dasd_stats_all_block_off(void)
{
int i;
struct dasd_device *device;
for (i = 0; i < dasd_max_devindex; ++i) {
device = dasd_device_from_devindex(i);
if (IS_ERR(device))
continue;
if (device->block)
dasd_profile_off(&device->block->profile);
dasd_put_device(device);
}
}
static void dasd_stats_all_block_reset(void)
{
int i;
struct dasd_device *device;
for (i = 0; i < dasd_max_devindex; ++i) {
device = dasd_device_from_devindex(i);
if (IS_ERR(device))
continue;
if (device->block)
dasd_profile_reset(&device->block->profile);
dasd_put_device(device);
}
}
static void dasd_statistics_array(struct seq_file *m, unsigned int *array, int factor)
{
int i;
for (i = 0; i < 32; i++) {
seq_printf(m, "%7d ", array[i] / factor);
if (i == 15)
seq_putc(m, '\n');
}
seq_putc(m, '\n');
}
#endif /* CONFIG_DASD_PROFILE */
static int dasd_stats_proc_show(struct seq_file *m, void *v)
{
#ifdef CONFIG_DASD_PROFILE
struct dasd_profile_info *prof;
int factor;
/* check for active profiling */
if (!dasd_global_profile_level) {
seq_printf(m, "Statistics are off - they might be "
"switched on using 'echo set on > "
"/proc/dasd/statistics'\n");
return 0;
}
prof = &dasd_global_profile_data;
/* prevent counter 'overflow' on output */
for (factor = 1; (prof->dasd_io_reqs / factor) > 9999999;
factor *= 10);
seq_printf(m, "%d dasd I/O requests\n", prof->dasd_io_reqs);
seq_printf(m, "with %u sectors(512B each)\n",
prof->dasd_io_sects);
seq_printf(m, "Scale Factor is %d\n", factor);
seq_printf(m,
" __<4 ___8 __16 __32 __64 _128 "
" _256 _512 __1k __2k __4k __8k "
" _16k _32k _64k 128k\n");
seq_printf(m,
" _256 _512 __1M __2M __4M __8M "
" _16M _32M _64M 128M 256M 512M "
" __1G __2G __4G " " _>4G\n");
seq_printf(m, "Histogram of sizes (512B secs)\n");
dasd_statistics_array(m, prof->dasd_io_secs, factor);
seq_printf(m, "Histogram of I/O times (microseconds)\n");
dasd_statistics_array(m, prof->dasd_io_times, factor);
seq_printf(m, "Histogram of I/O times per sector\n");
dasd_statistics_array(m, prof->dasd_io_timps, factor);
seq_printf(m, "Histogram of I/O time till ssch\n");
dasd_statistics_array(m, prof->dasd_io_time1, factor);
seq_printf(m, "Histogram of I/O time between ssch and irq\n");
dasd_statistics_array(m, prof->dasd_io_time2, factor);
seq_printf(m, "Histogram of I/O time between ssch "
"and irq per sector\n");
dasd_statistics_array(m, prof->dasd_io_time2ps, factor);
seq_printf(m, "Histogram of I/O time between irq and end\n");
dasd_statistics_array(m, prof->dasd_io_time3, factor);
seq_printf(m, "# of req in chanq at enqueuing (1..32) \n");
dasd_statistics_array(m, prof->dasd_io_nr_req, factor);
#else
seq_printf(m, "Statistics are not activated in this kernel\n");
#endif
return 0;
}
static int dasd_stats_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, dasd_stats_proc_show, NULL);
}
static ssize_t dasd_stats_proc_write(struct file *file,
const char __user *user_buf, size_t user_len, loff_t *pos)
{
#ifdef CONFIG_DASD_PROFILE
char *buffer, *str;
int rc;
if (user_len > 65536)
user_len = 65536;
buffer = dasd_get_user_string(user_buf, user_len);
if (IS_ERR(buffer))
return PTR_ERR(buffer);
/* check for valid verbs */
str = skip_spaces(buffer);
if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
/* 'set xxx' was given */
str = skip_spaces(str + 4);
if (strcmp(str, "on") == 0) {
/* switch on statistics profiling */
rc = dasd_stats_all_block_on();
if (rc) {
dasd_stats_all_block_off();
goto out_error;
}
dasd_global_profile_reset();
dasd_global_profile_level = DASD_PROFILE_ON;
pr_info("The statistics feature has been switched "
"on\n");
} else if (strcmp(str, "off") == 0) {
/* switch off and reset statistics profiling */
dasd_global_profile_level = DASD_PROFILE_OFF;
dasd_global_profile_reset();
dasd_stats_all_block_off();
pr_info("The statistics feature has been switched "
"off\n");
} else
goto out_parse_error;
} else if (strncmp(str, "reset", 5) == 0) {
/* reset the statistics */
dasd_global_profile_reset();
dasd_stats_all_block_reset();
pr_info("The statistics have been reset\n");
} else
goto out_parse_error;
vfree(buffer);
return user_len;
out_parse_error:
rc = -EINVAL;
pr_warning("%s is not a supported value for /proc/dasd/statistics\n",
str);
out_error:
vfree(buffer);
return rc;
#else
pr_warning("/proc/dasd/statistics: is not activated in this kernel\n");
return user_len;
#endif /* CONFIG_DASD_PROFILE */
}
static const struct file_operations dasd_stats_proc_fops = {
.owner = THIS_MODULE,
.open = dasd_stats_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.write = dasd_stats_proc_write,
};
/*
* Create dasd proc-fs entries.
* In case creation failed, cleanup and return -ENOENT.
*/
int
dasd_proc_init(void)
{
dasd_proc_root_entry = proc_mkdir("dasd", NULL);
if (!dasd_proc_root_entry)
goto out_nodasd;
dasd_devices_entry = proc_create("devices",
S_IFREG | S_IRUGO | S_IWUSR,
dasd_proc_root_entry,
&dasd_devices_file_ops);
if (!dasd_devices_entry)
goto out_nodevices;
dasd_statistics_entry = proc_create("statistics",
S_IFREG | S_IRUGO | S_IWUSR,
dasd_proc_root_entry,
&dasd_stats_proc_fops);
if (!dasd_statistics_entry)
goto out_nostatistics;
return 0;
out_nostatistics:
remove_proc_entry("devices", dasd_proc_root_entry);
out_nodevices:
remove_proc_entry("dasd", NULL);
out_nodasd:
return -ENOENT;
}
void
dasd_proc_exit(void)
{
remove_proc_entry("devices", dasd_proc_root_entry);
remove_proc_entry("statistics", dasd_proc_root_entry);
remove_proc_entry("dasd", NULL);
}