linux/drivers/s390/char/tape_proc.c
Michael Holzheu 66a464dbc8 [PATCH] s390: debug feature changes
This patch changes the memory allocation method for the s390 debug feature.
Trace buffers had been allocated using the get_free_pages() function before.
Therefore it was not possible to get big memory areas in a running system due
to memory fragmentation.  Now the trace buffers are subdivided into several
subbuffers with pagesize.  Therefore it is now possible to allocate more
memory for the trace buffers and more trace records can be written.

In addition to that, dynamic specification of the size of the trace buffers is
implemented.  It is now possible to change the size of a trace buffer using a
new debugfs file instance.  When writing a number into this file, the trace
buffer size is changed to 'number * pagesize'.

In the past all the traces could be obtained from userspace by accessing files
in the "proc" filesystem.  Now with debugfs we have a new filesystem which
should be used for debugging purposes.  This patch moves the debug feature
from procfs to debugfs.

Since the interface of debug_register() changed, all device drivers, which use
the debug feature had to be adjusted.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:37 -07:00

147 lines
3.4 KiB
C

/*
* drivers/s390/char/tape.c
* tape device driver for S/390 and zSeries tapes.
*
* S390 and zSeries version
* Copyright (C) 2001 IBM Corporation
* Author(s): Carsten Otte <cotte@de.ibm.com>
* Michael Holzheu <holzheu@de.ibm.com>
* Tuan Ngo-Anh <ngoanh@de.ibm.com>
*
* PROCFS Functions
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
#define TAPE_DBF_AREA tape_core_dbf
#include "tape.h"
#define PRINTK_HEADER "TAPE_PROC: "
static const char *tape_med_st_verbose[MS_SIZE] =
{
[MS_UNKNOWN] = "UNKNOWN ",
[MS_LOADED] = "LOADED ",
[MS_UNLOADED] = "UNLOADED"
};
/* our proc tapedevices entry */
static struct proc_dir_entry *tape_proc_devices;
/*
* Show function for /proc/tapedevices
*/
static int tape_proc_show(struct seq_file *m, void *v)
{
struct tape_device *device;
struct tape_request *request;
const char *str;
unsigned long n;
n = (unsigned long) v - 1;
if (!n) {
seq_printf(m, "TapeNo\tBusID CuType/Model\t"
"DevType/Model\tBlkSize\tState\tOp\tMedState\n");
}
device = tape_get_device(n);
if (IS_ERR(device))
return 0;
spin_lock_irq(get_ccwdev_lock(device->cdev));
seq_printf(m, "%d\t", (int) n);
seq_printf(m, "%-10.10s ", device->cdev->dev.bus_id);
seq_printf(m, "%04X/", device->cdev->id.cu_type);
seq_printf(m, "%02X\t", device->cdev->id.cu_model);
seq_printf(m, "%04X/", device->cdev->id.dev_type);
seq_printf(m, "%02X\t\t", device->cdev->id.dev_model);
if (device->char_data.block_size == 0)
seq_printf(m, "auto\t");
else
seq_printf(m, "%i\t", device->char_data.block_size);
if (device->tape_state >= 0 &&
device->tape_state < TS_SIZE)
str = tape_state_verbose[device->tape_state];
else
str = "UNKNOWN";
seq_printf(m, "%s\t", str);
if (!list_empty(&device->req_queue)) {
request = list_entry(device->req_queue.next,
struct tape_request, list);
str = tape_op_verbose[request->op];
} else
str = "---";
seq_printf(m, "%s\t", str);
seq_printf(m, "%s\n", tape_med_st_verbose[device->medium_state]);
spin_unlock_irq(get_ccwdev_lock(device->cdev));
tape_put_device(device);
return 0;
}
static void *tape_proc_start(struct seq_file *m, loff_t *pos)
{
if (*pos >= 256 / TAPE_MINORS_PER_DEV)
return NULL;
return (void *)((unsigned long) *pos + 1);
}
static void *tape_proc_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return tape_proc_start(m, pos);
}
static void tape_proc_stop(struct seq_file *m, void *v)
{
}
static struct seq_operations tape_proc_seq = {
.start = tape_proc_start,
.next = tape_proc_next,
.stop = tape_proc_stop,
.show = tape_proc_show,
};
static int tape_proc_open(struct inode *inode, struct file *file)
{
return seq_open(file, &tape_proc_seq);
}
static struct file_operations tape_proc_ops =
{
.open = tape_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
/*
* Initialize procfs stuff on startup
*/
void
tape_proc_init(void)
{
tape_proc_devices =
create_proc_entry ("tapedevices", S_IFREG | S_IRUGO | S_IWUSR,
&proc_root);
if (tape_proc_devices == NULL) {
PRINT_WARN("tape: Cannot register procfs entry tapedevices\n");
return;
}
tape_proc_devices->proc_fops = &tape_proc_ops;
tape_proc_devices->owner = THIS_MODULE;
}
/*
* Cleanup all stuff registered to the procfs
*/
void
tape_proc_cleanup(void)
{
if (tape_proc_devices != NULL)
remove_proc_entry ("tapedevices", &proc_root);
}