summaryrefslogtreecommitdiff
path: root/fs/ext4/sysfs.c
blob: 1205261f130cbfa8ae82632399aa7beb73e4cc6a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/ext4/sysfs.c
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Theodore Ts'o (tytso@mit.edu)
 *
 */

#include <linux/time.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>

#include "ext4.h"
#include "ext4_jbd2.h"

typedef enum {
	attr_noop,
	attr_delayed_allocation_blocks,
	attr_session_write_kbytes,
	attr_lifetime_write_kbytes,
	attr_reserved_clusters,
	attr_inode_readahead,
	attr_trigger_test_error,
	attr_feature,
	attr_pointer_ui,
	attr_pointer_atomic,
} attr_id_t;

typedef enum {
	ptr_explicit,
	ptr_ext4_sb_info_offset,
	ptr_ext4_super_block_offset,
} attr_ptr_t;

static const char proc_dirname[] = "fs/ext4";
static struct proc_dir_entry *ext4_proc_root;

struct ext4_attr {
	struct attribute attr;
	short attr_id;
	short attr_ptr;
	union {
		int offset;
		void *explicit_ptr;
	} u;
};

static ssize_t session_write_kbytes_show(struct ext4_attr *a,
					 struct ext4_sb_info *sbi, char *buf)
{
	struct super_block *sb = sbi->s_buddy_cache->i_sb;

	if (!sb->s_bdev->bd_part)
		return snprintf(buf, PAGE_SIZE, "0\n");
	return snprintf(buf, PAGE_SIZE, "%lu\n",
			(part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
			 sbi->s_sectors_written_start) >> 1);
}

static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
					  struct ext4_sb_info *sbi, char *buf)
{
	struct super_block *sb = sbi->s_buddy_cache->i_sb;

	if (!sb->s_bdev->bd_part)
		return snprintf(buf, PAGE_SIZE, "0\n");
	return snprintf(buf, PAGE_SIZE, "%llu\n",
			(unsigned long long)(sbi->s_kbytes_written +
			((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
			  EXT4_SB(sb)->s_sectors_written_start) >> 1)));
}

static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
					  struct ext4_sb_info *sbi,
					  const char *buf, size_t count)
{
	unsigned long t;
	int ret;

	ret = kstrtoul(skip_spaces(buf), 0, &t);
	if (ret)
		return ret;

	if (t && (!is_power_of_2(t) || t > 0x40000000))
		return -EINVAL;

	sbi->s_inode_readahead_blks = t;
	return count;
}

static ssize_t reserved_clusters_store(struct ext4_attr *a,
				   struct ext4_sb_info *sbi,
				   const char *buf, size_t count)
{
	unsigned long long val;
	ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>
				 sbi->s_cluster_bits);
	int ret;

	ret = kstrtoull(skip_spaces(buf), 0, &val);
	if (ret || val >= clusters)
		return -EINVAL;

	atomic64_set(&sbi->s_resv_clusters, val);
	return count;
}

static ssize_t trigger_test_error(struct ext4_attr *a,
				  struct ext4_sb_info *sbi,
				  const char *buf, size_t count)
{
	int len = count;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (len && buf[len-1] == '\n')
		len--;

	if (len)
		ext4_error(sbi->s_sb, "%.*s", len, buf);
	return count;
}

#define EXT4_ATTR(_name,_mode,_id)					\
static struct ext4_attr ext4_attr_##_name = {				\
	.attr = {.name = __stringify(_name), .mode = _mode },		\
	.attr_id = attr_##_id,						\
}

#define EXT4_ATTR_FUNC(_name,_mode)  EXT4_ATTR(_name,_mode,_name)

#define EXT4_ATTR_FEATURE(_name)   EXT4_ATTR(_name, 0444, feature)

#define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname)	\
static struct ext4_attr ext4_attr_##_name = {			\
	.attr = {.name = __stringify(_name), .mode = _mode },	\
	.attr_id = attr_##_id,					\
	.attr_ptr = ptr_##_struct##_offset,			\
	.u = {							\
		.offset = offsetof(struct _struct, _elname),\
	},							\
}

#define EXT4_RO_ATTR_ES_UI(_name,_elname)				\
	EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)

#define EXT4_RW_ATTR_SBI_UI(_name,_elname)	\
	EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)

#define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
static struct ext4_attr ext4_attr_##_name = {			\
	.attr = {.name = __stringify(_name), .mode = _mode },	\
	.attr_id = attr_##_id,					\
	.attr_ptr = ptr_explicit,				\
	.u = {							\
		.explicit_ptr = _ptr,				\
	},							\
}

#define ATTR_LIST(name) &ext4_attr_##name.attr

EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444);
EXT4_ATTR_FUNC(session_write_kbytes, 0444);
EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);
EXT4_ATTR_FUNC(reserved_clusters, 0644);

EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
		 ext4_sb_info, s_inode_readahead_blks);
EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);

static unsigned int old_bump_val = 128;
EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);

static struct attribute *ext4_attrs[] = {
	ATTR_LIST(delayed_allocation_blocks),
	ATTR_LIST(session_write_kbytes),
	ATTR_LIST(lifetime_write_kbytes),
	ATTR_LIST(reserved_clusters),
	ATTR_LIST(inode_readahead_blks),
	ATTR_LIST(inode_goal),
	ATTR_LIST(mb_stats),
	ATTR_LIST(mb_max_to_scan),
	ATTR_LIST(mb_min_to_scan),
	ATTR_LIST(mb_order2_req),
	ATTR_LIST(mb_stream_req),
	ATTR_LIST(mb_group_prealloc),
	ATTR_LIST(max_writeback_mb_bump),
	ATTR_LIST(extent_max_zeroout_kb),
	ATTR_LIST(trigger_fs_error),
	ATTR_LIST(err_ratelimit_interval_ms),
	ATTR_LIST(err_ratelimit_burst),
	ATTR_LIST(warning_ratelimit_interval_ms),
	ATTR_LIST(warning_ratelimit_burst),
	ATTR_LIST(msg_ratelimit_interval_ms),
	ATTR_LIST(msg_ratelimit_burst),
	ATTR_LIST(errors_count),
	ATTR_LIST(first_error_time),
	ATTR_LIST(last_error_time),
	NULL,
};

/* Features this copy of ext4 supports */
EXT4_ATTR_FEATURE(lazy_itable_init);
EXT4_ATTR_FEATURE(batched_discard);
EXT4_ATTR_FEATURE(meta_bg_resize);
#ifdef CONFIG_EXT4_FS_ENCRYPTION
EXT4_ATTR_FEATURE(encryption);
#endif
EXT4_ATTR_FEATURE(metadata_csum_seed);

static struct attribute *ext4_feat_attrs[] = {
	ATTR_LIST(lazy_itable_init),
	ATTR_LIST(batched_discard),
	ATTR_LIST(meta_bg_resize),
#ifdef CONFIG_EXT4_FS_ENCRYPTION
	ATTR_LIST(encryption),
#endif
	ATTR_LIST(metadata_csum_seed),
	NULL,
};

static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
{
	switch (a->attr_ptr) {
	case ptr_explicit:
		return a->u.explicit_ptr;
	case ptr_ext4_sb_info_offset:
		return (void *) (((char *) sbi) + a->u.offset);
	case ptr_ext4_super_block_offset:
		return (void *) (((char *) sbi->s_es) + a->u.offset);
	}
	return NULL;
}

static ssize_t ext4_attr_show(struct kobject *kobj,
			      struct attribute *attr, char *buf)
{
	struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
						s_kobj);
	struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
	void *ptr = calc_ptr(a, sbi);

	switch (a->attr_id) {
	case attr_delayed_allocation_blocks:
		return snprintf(buf, PAGE_SIZE, "%llu\n",
				(s64) EXT4_C2B(sbi,
		       percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
	case attr_session_write_kbytes:
		return session_write_kbytes_show(a, sbi, buf);
	case attr_lifetime_write_kbytes:
		return lifetime_write_kbytes_show(a, sbi, buf);
	case attr_reserved_clusters:
		return snprintf(buf, PAGE_SIZE, "%llu\n",
				(unsigned long long)
				atomic64_read(&sbi->s_resv_clusters));
	case attr_inode_readahead:
	case attr_pointer_ui:
		if (!ptr)
			return 0;
		return snprintf(buf, PAGE_SIZE, "%u\n",
				*((unsigned int *) ptr));
	case attr_pointer_atomic:
		if (!ptr)
			return 0;
		return snprintf(buf, PAGE_SIZE, "%d\n",
				atomic_read((atomic_t *) ptr));
	case attr_feature:
		return snprintf(buf, PAGE_SIZE, "supported\n");
	}

	return 0;
}

static ssize_t ext4_attr_store(struct kobject *kobj,
			       struct attribute *attr,
			       const char *buf, size_t len)
{
	struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
						s_kobj);
	struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
	void *ptr = calc_ptr(a, sbi);
	unsigned long t;
	int ret;

	switch (a->attr_id) {
	case attr_reserved_clusters:
		return reserved_clusters_store(a, sbi, buf, len);
	case attr_pointer_ui:
		if (!ptr)
			return 0;
		ret = kstrtoul(skip_spaces(buf), 0, &t);
		if (ret)
			return ret;
		*((unsigned int *) ptr) = t;
		return len;
	case attr_inode_readahead:
		return inode_readahead_blks_store(a, sbi, buf, len);
	case attr_trigger_test_error:
		return trigger_test_error(a, sbi, buf, len);
	}
	return 0;
}

static void ext4_sb_release(struct kobject *kobj)
{
	struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
						s_kobj);
	complete(&sbi->s_kobj_unregister);
}

static void ext4_kset_release(struct kobject *kobj)
{
	struct kset *kset = container_of(kobj, struct kset, kobj);

	kfree(kset);
}

static const struct sysfs_ops ext4_attr_ops = {
	.show	= ext4_attr_show,
	.store	= ext4_attr_store,
};

static struct kobj_type ext4_sb_ktype = {
	.default_attrs	= ext4_attrs,
	.sysfs_ops	= &ext4_attr_ops,
	.release	= ext4_sb_release,
};

static struct kobj_type ext4_ktype = {
	.sysfs_ops	= &ext4_attr_ops,
	.release	= ext4_kset_release,
};

static struct kset *ext4_kset;

static struct kobj_type ext4_feat_ktype = {
	.default_attrs	= ext4_feat_attrs,
	.sysfs_ops	= &ext4_attr_ops,
	.release	= (void (*)(struct kobject *))kfree,
};

static struct kobject *ext4_feat;

#define PROC_FILE_SHOW_DEFN(name) \
static int name##_open(struct inode *inode, struct file *file) \
{ \
	return single_open(file, ext4_seq_##name##_show, PDE_DATA(inode)); \
} \
\
static const struct file_operations ext4_seq_##name##_fops = { \
	.open		= name##_open, \
	.read		= seq_read, \
	.llseek		= seq_lseek, \
	.release	= single_release, \
}

#define PROC_FILE_LIST(name) \
	{ __stringify(name), &ext4_seq_##name##_fops }

PROC_FILE_SHOW_DEFN(es_shrinker_info);
PROC_FILE_SHOW_DEFN(options);

static const struct ext4_proc_files {
	const char *name;
	const struct file_operations *fops;
} proc_files[] = {
	PROC_FILE_LIST(options),
	PROC_FILE_LIST(es_shrinker_info),
	PROC_FILE_LIST(mb_groups),
	{ NULL, NULL },
};

int ext4_register_sysfs(struct super_block *sb)
{
	struct ext4_sb_info *sbi = EXT4_SB(sb);
	const struct ext4_proc_files *p;
	int err;

	sbi->s_kobj.kset = ext4_kset;
	init_completion(&sbi->s_kobj_unregister);
	err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL,
				   "%s", sb->s_id);
	if (err) {
		kobject_put(&sbi->s_kobj);
		wait_for_completion(&sbi->s_kobj_unregister);
		return err;
	}

	if (ext4_proc_root)
		sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);

	if (sbi->s_proc) {
		for (p = proc_files; p->name; p++)
			proc_create_data(p->name, S_IRUGO, sbi->s_proc,
					 p->fops, sb);
	}
	return 0;
}

void ext4_unregister_sysfs(struct super_block *sb)
{
	struct ext4_sb_info *sbi = EXT4_SB(sb);
	const struct ext4_proc_files *p;

	if (sbi->s_proc) {
		for (p = proc_files; p->name; p++)
			remove_proc_entry(p->name, sbi->s_proc);
		remove_proc_entry(sb->s_id, ext4_proc_root);
	}
	kobject_del(&sbi->s_kobj);
}

int __init ext4_init_sysfs(void)
{
	int ret;

	ext4_kset = kzalloc(sizeof(*ext4_kset), GFP_KERNEL);
	if (!ext4_kset)
		return -ENOMEM;

	kobject_set_name(&ext4_kset->kobj, "ext4");
	ext4_kset->kobj.parent = fs_kobj;
	ext4_kset->kobj.ktype = &ext4_ktype;
	ret = kset_register(ext4_kset);
	if (ret)
		goto kset_err;

	ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
	if (!ext4_feat) {
		ret = -ENOMEM;
		goto kset_err;
	}

	ext4_feat->kset = ext4_kset;
	ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
				   NULL, "features");
	if (ret)
		goto feat_err;

	ext4_proc_root = proc_mkdir(proc_dirname, NULL);
	return ret;

feat_err:
	kobject_put(ext4_feat);
kset_err:
	kset_unregister(ext4_kset);
	ext4_kset = NULL;
	return ret;
}

void ext4_exit_sysfs(void)
{
	kobject_put(ext4_feat);
	kset_unregister(ext4_kset);
	ext4_kset = NULL;
	remove_proc_entry(proc_dirname, NULL);
	ext4_proc_root = NULL;
}