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#include <linux/init.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/module.h>
#include "debugfs.h"
static struct dentry *d_xen_debug;
struct dentry * __init xen_init_debugfs(void)
{
if (!d_xen_debug) {
d_xen_debug = debugfs_create_dir("xen", NULL);
if (!d_xen_debug)
pr_warning("Could not create 'xen' debugfs directory\n");
}
return d_xen_debug;
}
struct array_data
{
void *array;
unsigned elements;
};
static int u32_array_open(struct inode *inode, struct file *file)
{
file->private_data = NULL;
return nonseekable_open(inode, file);
}
static size_t format_array(char *buf, size_t bufsize, const char *fmt,
u32 *array, unsigned array_size)
{
size_t ret = 0;
unsigned i;
for(i = 0; i < array_size; i++) {
size_t len;
len = snprintf(buf, bufsize, fmt, array[i]);
len++; /* ' ' or '\n' */
ret += len;
if (buf) {
buf += len;
bufsize -= len;
buf[-1] = (i == array_size-1) ? '\n' : ' ';
}
}
ret++; /* \0 */
if (buf)
*buf = '\0';
return ret;
}
static char *format_array_alloc(const char *fmt, u32 *array, unsigned array_size)
{
size_t len = format_array(NULL, 0, fmt, array, array_size);
char *ret;
ret = kmalloc(len, GFP_KERNEL);
if (ret == NULL)
return NULL;
format_array(ret, len, fmt, array, array_size);
return ret;
}
static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
struct inode *inode = file->f_path.dentry->d_inode;
struct array_data *data = inode->i_private;
size_t size;
if (*ppos == 0) {
if (file->private_data) {
kfree(file->private_data);
file->private_data = NULL;
}
file->private_data = format_array_alloc("%u", data->array, data->elements);
}
size = 0;
if (file->private_data)
size = strlen(file->private_data);
return simple_read_from_buffer(buf, len, ppos, file->private_data, size);
}
static int xen_array_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
return 0;
}
static const struct file_operations u32_array_fops = {
.owner = THIS_MODULE,
.open = u32_array_open,
.release= xen_array_release,
.read = u32_array_read,
.llseek = no_llseek,
};
struct dentry *xen_debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, unsigned elements)
{
struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
if (data == NULL)
return NULL;
data->array = array;
data->elements = elements;
return debugfs_create_file(name, mode, parent, data, &u32_array_fops);
}
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