1 #include <linux/init.h>
2 #include <linux/debugfs.h>
3 #include <linux/slab.h>
4 #include <linux/module.h>
8 static struct dentry *d_xen_debug;
10 struct dentry * __init xen_init_debugfs(void)
13 d_xen_debug = debugfs_create_dir("xen", NULL);
16 pr_warning("Could not create 'xen' debugfs directory\n");
28 static int u32_array_open(struct inode *inode, struct file *file)
30 file->private_data = NULL;
31 return nonseekable_open(inode, file);
34 static size_t format_array(char *buf, size_t bufsize, const char *fmt,
35 u32 *array, unsigned array_size)
40 for(i = 0; i < array_size; i++) {
43 len = snprintf(buf, bufsize, fmt, array[i]);
44 len++; /* ' ' or '\n' */
50 buf[-1] = (i == array_size-1) ? '\n' : ' ';
61 static char *format_array_alloc(const char *fmt, u32 *array, unsigned array_size)
63 size_t len = format_array(NULL, 0, fmt, array, array_size);
66 ret = kmalloc(len, GFP_KERNEL);
70 format_array(ret, len, fmt, array, array_size);
74 static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
77 struct inode *inode = file->f_path.dentry->d_inode;
78 struct array_data *data = inode->i_private;
82 if (file->private_data) {
83 kfree(file->private_data);
84 file->private_data = NULL;
87 file->private_data = format_array_alloc("%u", data->array, data->elements);
91 if (file->private_data)
92 size = strlen(file->private_data);
94 return simple_read_from_buffer(buf, len, ppos, file->private_data, size);
97 static int xen_array_release(struct inode *inode, struct file *file)
99 kfree(file->private_data);
104 static const struct file_operations u32_array_fops = {
105 .owner = THIS_MODULE,
106 .open = u32_array_open,
107 .release= xen_array_release,
108 .read = u32_array_read,
112 struct dentry *xen_debugfs_create_u32_array(const char *name, umode_t mode,
113 struct dentry *parent,
114 u32 *array, unsigned elements)
116 struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
122 data->elements = elements;
124 return debugfs_create_file(name, mode, parent, data, &u32_array_fops);