[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / oprofile / oprofilefs.c

/**
 * @file oprofilefs.c
 *
 * @remark Copyright 2002 OProfile authors
 * @remark Read the file COPYING
 *
 * @author John Levon
 *
 * A simple filesystem for configuration and
 * access of oprofile.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/oprofile.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <asm/uaccess.h>

#include "oprof.h"

#define OPROFILEFS_MAGIC 0x6f70726f

DEFINE_SPINLOCK(oprofilefs_lock);

static struct inode * oprofilefs_get_inode(struct super_block * sb, int mode)
{
	struct inode * inode = new_inode(sb);

	if (inode) {
		inode->i_mode = mode;
		inode->i_uid = 0;
		inode->i_gid = 0;
		inode->i_blksize = PAGE_CACHE_SIZE;
		inode->i_blocks = 0;
		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	}
	return inode;
}


static struct super_operations s_ops = {
	.statfs		= simple_statfs,
	.drop_inode 	= generic_delete_inode,
};


ssize_t oprofilefs_str_to_user(char const * str, char __user * buf, size_t count, loff_t * offset)
{
	return simple_read_from_buffer(buf, count, offset, str, strlen(str));
}


#define TMPBUFSIZE 50

ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user * buf, size_t count, loff_t * offset)
{
	char tmpbuf[TMPBUFSIZE];
	size_t maxlen = snprintf(tmpbuf, TMPBUFSIZE, "%lu\n", val);
	if (maxlen > TMPBUFSIZE)
		maxlen = TMPBUFSIZE;
	return simple_read_from_buffer(buf, count, offset, tmpbuf, maxlen);
}


int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count)
{
	char tmpbuf[TMPBUFSIZE];

	if (!count)
		return 0;

	if (count > TMPBUFSIZE - 1)
		return -EINVAL;

	memset(tmpbuf, 0x0, TMPBUFSIZE);

	if (copy_from_user(tmpbuf, buf, count))
		return -EFAULT;

	spin_lock(&oprofilefs_lock);
	*val = simple_strtoul(tmpbuf, NULL, 0);
	spin_unlock(&oprofilefs_lock);
	return 0;
}


static ssize_t ulong_read_file(struct file * file, char __user * buf, size_t count, loff_t * offset)
{
	unsigned long * val = file->private_data;
	return oprofilefs_ulong_to_user(*val, buf, count, offset);
}


static ssize_t ulong_write_file(struct file * file, char const __user * buf, size_t count, loff_t * offset)
{
	unsigned long * value = file->private_data;
	int retval;

	if (*offset)
		return -EINVAL;

	retval = oprofilefs_ulong_from_user(value, buf, count);

	if (retval)
		return retval;
	return count;
}


static int default_open(struct inode * inode, struct file * filp)
{
	if (inode->u.generic_ip)
		filp->private_data = inode->u.generic_ip;
	return 0;
}


static struct file_operations ulong_fops = {
	.read		= ulong_read_file,
	.write		= ulong_write_file,
	.open		= default_open,
};


static struct file_operations ulong_ro_fops = {
	.read		= ulong_read_file,
	.open		= default_open,
};


static struct dentry * __oprofilefs_create_file(struct super_block * sb,
	struct dentry * root, char const * name, struct file_operations * fops,
	int perm)
{
	struct dentry * dentry;
	struct inode * inode;

	dentry = d_alloc_name(root, name);
	if (!dentry)
		return NULL;
	inode = oprofilefs_get_inode(sb, S_IFREG | perm);
	if (!inode) {
		dput(dentry);
		return NULL;
	}
	inode->i_fop = fops;
	d_add(dentry, inode);
	return dentry;
}


int oprofilefs_create_ulong(struct super_block * sb, struct dentry * root,
	char const * name, unsigned long * val)
{
	struct dentry * d = __oprofilefs_create_file(sb, root, name,
						     &ulong_fops, 0644);
	if (!d)
		return -EFAULT;

	d->d_inode->u.generic_ip = val;
	return 0;
}


int oprofilefs_create_ro_ulong(struct super_block * sb, struct dentry * root,
	char const * name, unsigned long * val)
{
	struct dentry * d = __oprofilefs_create_file(sb, root, name,
						     &ulong_ro_fops, 0444);
	if (!d)
		return -EFAULT;

	d->d_inode->u.generic_ip = val;
	return 0;
}


static ssize_t atomic_read_file(struct file * file, char __user * buf, size_t count, loff_t * offset)
{
	atomic_t * val = file->private_data;
	return oprofilefs_ulong_to_user(atomic_read(val), buf, count, offset);
}
 

static struct file_operations atomic_ro_fops = {
	.read		= atomic_read_file,
	.open		= default_open,
};
 

int oprofilefs_create_ro_atomic(struct super_block * sb, struct dentry * root,
	char const * name, atomic_t * val)
{
	struct dentry * d = __oprofilefs_create_file(sb, root, name,
						     &atomic_ro_fops, 0444);
	if (!d)
		return -EFAULT;

	d->d_inode->u.generic_ip = val;
	return 0;
}

 
int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
	char const * name, struct file_operations * fops)
{
	if (!__oprofilefs_create_file(sb, root, name, fops, 0644))
		return -EFAULT;
	return 0;
}


int oprofilefs_create_file_perm(struct super_block * sb, struct dentry * root,
	char const * name, struct file_operations * fops, int perm)
{
	if (!__oprofilefs_create_file(sb, root, name, fops, perm))
		return -EFAULT;
	return 0;
}


struct dentry * oprofilefs_mkdir(struct super_block * sb,
	struct dentry * root, char const * name)
{
	struct dentry * dentry;
	struct inode * inode;

	dentry = d_alloc_name(root, name);
	if (!dentry)
		return NULL;
	inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
	if (!inode) {
		dput(dentry);
		return NULL;
	}
	inode->i_op = &simple_dir_inode_operations;
	inode->i_fop = &simple_dir_operations;
	d_add(dentry, inode);
	return dentry;
}


static int oprofilefs_fill_super(struct super_block * sb, void * data, int silent)
{
	struct inode * root_inode;
	struct dentry * root_dentry;

	sb->s_blocksize = PAGE_CACHE_SIZE;
	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	sb->s_magic = OPROFILEFS_MAGIC;
	sb->s_op = &s_ops;
	sb->s_time_gran = 1;

	root_inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
	if (!root_inode)
		return -ENOMEM;
	root_inode->i_op = &simple_dir_inode_operations;
	root_inode->i_fop = &simple_dir_operations;
	root_dentry = d_alloc_root(root_inode);
	if (!root_dentry) {
		iput(root_inode);
		return -ENOMEM;
	}

	sb->s_root = root_dentry;

	oprofile_create_files(sb, root_dentry);

	// FIXME: verify kill_litter_super removes our dentries
	return 0;
}


static struct super_block *oprofilefs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return get_sb_single(fs_type, flags, data, oprofilefs_fill_super);
}


static struct file_system_type oprofilefs_type = {
	.owner		= THIS_MODULE,
	.name		= "oprofilefs",
	.get_sb		= oprofilefs_get_sb,
	.kill_sb	= kill_litter_super,
};


int __init oprofilefs_register(void)
{
	return register_filesystem(&oprofilefs_type);
}


void __exit oprofilefs_unregister(void)
{
	unregister_filesystem(&oprofilefs_type);
}
Commit	Line	Data
1da177e4 LT	1	/**
	2	* @file oprofilefs.c
	3	*
	4	* @remark Copyright 2002 OProfile authors
	5	* @remark Read the file COPYING
	6	*
	7	* @author John Levon
	8	*
	9	* A simple filesystem for configuration and
	10	* access of oprofile.
	11	*/
	12
	13	#include <linux/init.h>
	14	#include <linux/module.h>
	15	#include <linux/oprofile.h>
	16	#include <linux/fs.h>
	17	#include <linux/pagemap.h>
	18	#include <asm/uaccess.h>
	19
	20	#include "oprof.h"
	21
	22	#define OPROFILEFS_MAGIC 0x6f70726f
	23
	24	DEFINE_SPINLOCK(oprofilefs_lock);
	25
	26	static struct inode * oprofilefs_get_inode(struct super_block * sb, int mode)
	27	{
	28	struct inode * inode = new_inode(sb);
	29
	30	if (inode) {
	31	inode->i_mode = mode;
	32	inode->i_uid = 0;
	33	inode->i_gid = 0;
	34	inode->i_blksize = PAGE_CACHE_SIZE;
	35	inode->i_blocks = 0;
	36	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	37	}
	38	return inode;
	39	}
	40
	41
	42	static struct super_operations s_ops = {
	43	.statfs = simple_statfs,
	44	.drop_inode = generic_delete_inode,
	45	};
	46
	47
	48	ssize_t oprofilefs_str_to_user(char const * str, char __user * buf, size_t count, loff_t * offset)
	49	{
	50	return simple_read_from_buffer(buf, count, offset, str, strlen(str));
	51	}
	52
	53
	54	#define TMPBUFSIZE 50
	55
	56	ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user * buf, size_t count, loff_t * offset)
	57	{
	58	char tmpbuf[TMPBUFSIZE];
	59	size_t maxlen = snprintf(tmpbuf, TMPBUFSIZE, "%lu\n", val);
	60	if (maxlen > TMPBUFSIZE)
	61	maxlen = TMPBUFSIZE;
	62	return simple_read_from_buffer(buf, count, offset, tmpbuf, maxlen);
	63	}
	64
65
66	int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count)
67	{
68	char tmpbuf[TMPBUFSIZE];
69
70	if (!count)
71	return 0;
72
73	if (count > TMPBUFSIZE - 1)
74	return -EINVAL;
75
76	memset(tmpbuf, 0x0, TMPBUFSIZE);
77
78	if (copy_from_user(tmpbuf, buf, count))
79	return -EFAULT;
80
81	spin_lock(&oprofilefs_lock);
82	*val = simple_strtoul(tmpbuf, NULL, 0);
83	spin_unlock(&oprofilefs_lock);
84	return 0;
85	}
86
87
88	static ssize_t ulong_read_file(struct file * file, char __user * buf, size_t count, loff_t * offset)
89	{
90	unsigned long * val = file->private_data;
91	return oprofilefs_ulong_to_user(*val, buf, count, offset);
92	}
93
94
95	static ssize_t ulong_write_file(struct file * file, char const __user * buf, size_t count, loff_t * offset)
96	{
97	unsigned long * value = file->private_data;
98	int retval;
99
100	if (*offset)
101	return -EINVAL;
102
103	retval = oprofilefs_ulong_from_user(value, buf, count);
104
105	if (retval)
106	return retval;
107	return count;
108	}
109
110
111	static int default_open(struct inode * inode, struct file * filp)
112	{
113	if (inode->u.generic_ip)
114	filp->private_data = inode->u.generic_ip;
115	return 0;
116	}
117
118
119	static struct file_operations ulong_fops = {
120	.read = ulong_read_file,
121	.write = ulong_write_file,
122	.open = default_open,
123	};
124
125
126	static struct file_operations ulong_ro_fops = {
127	.read = ulong_read_file,
128	.open = default_open,
129	};
130
131
132	static struct dentry * __oprofilefs_create_file(struct super_block * sb,
133	struct dentry * root, char const * name, struct file_operations * fops,
134	int perm)
135	{
136	struct dentry * dentry;
137	struct inode * inode;
138
139	dentry = d_alloc_name(root, name);
140	if (!dentry)
141	return NULL;
142	inode = oprofilefs_get_inode(sb, S_IFREG \| perm);
143	if (!inode) {
144	dput(dentry);
145	return NULL;
146	}
147	inode->i_fop = fops;
148	d_add(dentry, inode);
149	return dentry;
150	}
151
152
153	int oprofilefs_create_ulong(struct super_block * sb, struct dentry * root,
154	char const * name, unsigned long * val)
155	{
156	struct dentry * d = __oprofilefs_create_file(sb, root, name,
157	&ulong_fops, 0644);
158	if (!d)
159	return -EFAULT;
160
161	d->d_inode->u.generic_ip = val;
162	return 0;
163	}
164
165
166	int oprofilefs_create_ro_ulong(struct super_block * sb, struct dentry * root,
167	char const * name, unsigned long * val)
168	{
169	struct dentry * d = __oprofilefs_create_file(sb, root, name,
170	&ulong_ro_fops, 0444);
171	if (!d)
172	return -EFAULT;
173
174	d->d_inode->u.generic_ip = val;
175	return 0;
176	}
177
178
179	static ssize_t atomic_read_file(struct file * file, char __user * buf, size_t count, loff_t * offset)
180	{
181	atomic_t * val = file->private_data;
182	return oprofilefs_ulong_to_user(atomic_read(val), buf, count, offset);
183	}
184
185
186	static struct file_operations atomic_ro_fops = {
187	.read = atomic_read_file,
188	.open = default_open,
189	};
190
191
192	int oprofilefs_create_ro_atomic(struct super_block * sb, struct dentry * root,
193	char const * name, atomic_t * val)
194	{
195	struct dentry * d = __oprofilefs_create_file(sb, root, name,
196	&atomic_ro_fops, 0444);
197	if (!d)
198	return -EFAULT;
199
200	d->d_inode->u.generic_ip = val;
201	return 0;
202	}
203
204
205	int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
206	char const * name, struct file_operations * fops)
207	{
208	if (!__oprofilefs_create_file(sb, root, name, fops, 0644))
209	return -EFAULT;
210	return 0;
211	}
212
213
214	int oprofilefs_create_file_perm(struct super_block * sb, struct dentry * root,
215	char const * name, struct file_operations * fops, int perm)
216	{
217	if (!__oprofilefs_create_file(sb, root, name, fops, perm))
218	return -EFAULT;
219	return 0;
220	}
221
222
223	struct dentry * oprofilefs_mkdir(struct super_block * sb,
224	struct dentry * root, char const * name)
225	{
226	struct dentry * dentry;
227	struct inode * inode;
228
229	dentry = d_alloc_name(root, name);
230	if (!dentry)
231	return NULL;
232	inode = oprofilefs_get_inode(sb, S_IFDIR \| 0755);
233	if (!inode) {
234	dput(dentry);
235	return NULL;
236	}
237	inode->i_op = &simple_dir_inode_operations;
238	inode->i_fop = &simple_dir_operations;
239	d_add(dentry, inode);
240	return dentry;
241	}
242
243
244	static int oprofilefs_fill_super(struct super_block * sb, void * data, int silent)
245	{
246	struct inode * root_inode;
247	struct dentry * root_dentry;
248
249	sb->s_blocksize = PAGE_CACHE_SIZE;
250	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
251	sb->s_magic = OPROFILEFS_MAGIC;
252	sb->s_op = &s_ops;
253	sb->s_time_gran = 1;
254
255	root_inode = oprofilefs_get_inode(sb, S_IFDIR \| 0755);
256	if (!root_inode)
257	return -ENOMEM;
258	root_inode->i_op = &simple_dir_inode_operations;
259	root_inode->i_fop = &simple_dir_operations;
260	root_dentry = d_alloc_root(root_inode);
261	if (!root_dentry) {
262	iput(root_inode);
263	return -ENOMEM;
264	}
265
266	sb->s_root = root_dentry;
267
268	oprofile_create_files(sb, root_dentry);
269
270	// FIXME: verify kill_litter_super removes our dentries
271	return 0;
272	}
273
274
275	static struct super_block oprofilefs_get_sb(struct file_system_type fs_type,
276	int flags, const char dev_name, void data)
277	{
278	return get_sb_single(fs_type, flags, data, oprofilefs_fill_super);
279	}
280
281
282	static struct file_system_type oprofilefs_type = {
283	.owner = THIS_MODULE,
284	.name = "oprofilefs",
285	.get_sb = oprofilefs_get_sb,
286	.kill_sb = kill_litter_super,
287	};
288
289
290	int __init oprofilefs_register(void)
291	{
292	return register_filesystem(&oprofilefs_type);
293	}
294
295
296	void __exit oprofilefs_unregister(void)
297	{
298	unregister_filesystem(&oprofilefs_type);
299	}