1 /*
2 * linux/fs/ext4/sysfs.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Theodore Ts'o (tytso@mit.edu)
7 *
8 */
9
10 #include <linux/time.h>
11 #include <linux/fs.h>
12 #include <linux/seq_file.h>
13 #include <linux/proc_fs.h>
14
15 #include "ext4.h"
16 #include "ext4_jbd2.h"
17
18 typedef enum {
19 attr_noop,
20 attr_delayed_allocation_blocks,
21 attr_session_write_kbytes,
22 attr_lifetime_write_kbytes,
23 attr_reserved_clusters,
24 attr_inode_readahead,
25 attr_trigger_test_error,
26 attr_feature,
27 attr_pointer_ui,
28 attr_pointer_atomic,
29 } attr_id_t;
30
31 typedef enum {
32 ptr_explicit,
33 ptr_ext4_sb_info_offset,
34 ptr_ext4_super_block_offset,
35 } attr_ptr_t;
36
37 static const char *proc_dirname = "fs/ext4";
38 static struct proc_dir_entry *ext4_proc_root;
39
40 struct ext4_attr {
41 struct attribute attr;
42 short attr_id;
43 short attr_ptr;
44 union {
45 int offset;
46 void *explicit_ptr;
47 } u;
48 };
49
session_write_kbytes_show(struct ext4_attr * a,struct ext4_sb_info * sbi,char * buf)50 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
51 struct ext4_sb_info *sbi, char *buf)
52 {
53 struct super_block *sb = sbi->s_buddy_cache->i_sb;
54
55 if (!sb->s_bdev->bd_part)
56 return snprintf(buf, PAGE_SIZE, "0\n");
57 return snprintf(buf, PAGE_SIZE, "%lu\n",
58 (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
59 sbi->s_sectors_written_start) >> 1);
60 }
61
lifetime_write_kbytes_show(struct ext4_attr * a,struct ext4_sb_info * sbi,char * buf)62 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
63 struct ext4_sb_info *sbi, char *buf)
64 {
65 struct super_block *sb = sbi->s_buddy_cache->i_sb;
66
67 if (!sb->s_bdev->bd_part)
68 return snprintf(buf, PAGE_SIZE, "0\n");
69 return snprintf(buf, PAGE_SIZE, "%llu\n",
70 (unsigned long long)(sbi->s_kbytes_written +
71 ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
72 EXT4_SB(sb)->s_sectors_written_start) >> 1)));
73 }
74
inode_readahead_blks_store(struct ext4_attr * a,struct ext4_sb_info * sbi,const char * buf,size_t count)75 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
76 struct ext4_sb_info *sbi,
77 const char *buf, size_t count)
78 {
79 unsigned long t;
80 int ret;
81
82 ret = kstrtoul(skip_spaces(buf), 0, &t);
83 if (ret)
84 return ret;
85
86 if (t && (!is_power_of_2(t) || t > 0x40000000))
87 return -EINVAL;
88
89 sbi->s_inode_readahead_blks = t;
90 return count;
91 }
92
reserved_clusters_store(struct ext4_attr * a,struct ext4_sb_info * sbi,const char * buf,size_t count)93 static ssize_t reserved_clusters_store(struct ext4_attr *a,
94 struct ext4_sb_info *sbi,
95 const char *buf, size_t count)
96 {
97 unsigned long long val;
98 ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>
99 sbi->s_cluster_bits);
100 int ret;
101
102 ret = kstrtoull(skip_spaces(buf), 0, &val);
103 if (ret || val >= clusters)
104 return -EINVAL;
105
106 atomic64_set(&sbi->s_resv_clusters, val);
107 return count;
108 }
109
trigger_test_error(struct ext4_attr * a,struct ext4_sb_info * sbi,const char * buf,size_t count)110 static ssize_t trigger_test_error(struct ext4_attr *a,
111 struct ext4_sb_info *sbi,
112 const char *buf, size_t count)
113 {
114 int len = count;
115
116 if (!capable(CAP_SYS_ADMIN))
117 return -EPERM;
118
119 if (len && buf[len-1] == '\n')
120 len--;
121
122 if (len)
123 ext4_error(sbi->s_sb, "%.*s", len, buf);
124 return count;
125 }
126
127 #define EXT4_ATTR(_name,_mode,_id) \
128 static struct ext4_attr ext4_attr_##_name = { \
129 .attr = {.name = __stringify(_name), .mode = _mode }, \
130 .attr_id = attr_##_id, \
131 }
132
133 #define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name)
134
135 #define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature)
136
137 #define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \
138 static struct ext4_attr ext4_attr_##_name = { \
139 .attr = {.name = __stringify(_name), .mode = _mode }, \
140 .attr_id = attr_##_id, \
141 .attr_ptr = ptr_##_struct##_offset, \
142 .u = { \
143 .offset = offsetof(struct _struct, _elname),\
144 }, \
145 }
146
147 #define EXT4_RO_ATTR_ES_UI(_name,_elname) \
148 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)
149
150 #define EXT4_RW_ATTR_SBI_UI(_name,_elname) \
151 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)
152
153 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
154 static struct ext4_attr ext4_attr_##_name = { \
155 .attr = {.name = __stringify(_name), .mode = _mode }, \
156 .attr_id = attr_##_id, \
157 .attr_ptr = ptr_explicit, \
158 .u = { \
159 .explicit_ptr = _ptr, \
160 }, \
161 }
162
163 #define ATTR_LIST(name) &ext4_attr_##name.attr
164
165 EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444);
166 EXT4_ATTR_FUNC(session_write_kbytes, 0444);
167 EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);
168 EXT4_ATTR_FUNC(reserved_clusters, 0644);
169
170 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
171 ext4_sb_info, s_inode_readahead_blks);
172 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
173 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
174 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
175 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
176 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
177 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
178 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
179 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
180 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
181 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
182 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
183 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
184 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
185 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
186 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
187 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
188 EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
189 EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);
190
191 static unsigned int old_bump_val = 128;
192 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
193
194 static struct attribute *ext4_attrs[] = {
195 ATTR_LIST(delayed_allocation_blocks),
196 ATTR_LIST(session_write_kbytes),
197 ATTR_LIST(lifetime_write_kbytes),
198 ATTR_LIST(reserved_clusters),
199 ATTR_LIST(inode_readahead_blks),
200 ATTR_LIST(inode_goal),
201 ATTR_LIST(mb_stats),
202 ATTR_LIST(mb_max_to_scan),
203 ATTR_LIST(mb_min_to_scan),
204 ATTR_LIST(mb_order2_req),
205 ATTR_LIST(mb_stream_req),
206 ATTR_LIST(mb_group_prealloc),
207 ATTR_LIST(max_writeback_mb_bump),
208 ATTR_LIST(extent_max_zeroout_kb),
209 ATTR_LIST(trigger_fs_error),
210 ATTR_LIST(err_ratelimit_interval_ms),
211 ATTR_LIST(err_ratelimit_burst),
212 ATTR_LIST(warning_ratelimit_interval_ms),
213 ATTR_LIST(warning_ratelimit_burst),
214 ATTR_LIST(msg_ratelimit_interval_ms),
215 ATTR_LIST(msg_ratelimit_burst),
216 ATTR_LIST(errors_count),
217 ATTR_LIST(first_error_time),
218 ATTR_LIST(last_error_time),
219 NULL,
220 };
221
222 /* Features this copy of ext4 supports */
223 EXT4_ATTR_FEATURE(lazy_itable_init);
224 EXT4_ATTR_FEATURE(batched_discard);
225 EXT4_ATTR_FEATURE(meta_bg_resize);
226 #ifdef CONFIG_EXT4_FS_ENCRYPTION
227 EXT4_ATTR_FEATURE(encryption);
228 #endif
229 EXT4_ATTR_FEATURE(metadata_csum_seed);
230
231 static struct attribute *ext4_feat_attrs[] = {
232 ATTR_LIST(lazy_itable_init),
233 ATTR_LIST(batched_discard),
234 ATTR_LIST(meta_bg_resize),
235 #ifdef CONFIG_EXT4_FS_ENCRYPTION
236 ATTR_LIST(encryption),
237 #endif
238 ATTR_LIST(metadata_csum_seed),
239 NULL,
240 };
241
calc_ptr(struct ext4_attr * a,struct ext4_sb_info * sbi)242 static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
243 {
244 switch (a->attr_ptr) {
245 case ptr_explicit:
246 return a->u.explicit_ptr;
247 case ptr_ext4_sb_info_offset:
248 return (void *) (((char *) sbi) + a->u.offset);
249 case ptr_ext4_super_block_offset:
250 return (void *) (((char *) sbi->s_es) + a->u.offset);
251 }
252 return NULL;
253 }
254
ext4_attr_show(struct kobject * kobj,struct attribute * attr,char * buf)255 static ssize_t ext4_attr_show(struct kobject *kobj,
256 struct attribute *attr, char *buf)
257 {
258 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
259 s_kobj);
260 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
261 void *ptr = calc_ptr(a, sbi);
262
263 switch (a->attr_id) {
264 case attr_delayed_allocation_blocks:
265 return snprintf(buf, PAGE_SIZE, "%llu\n",
266 (s64) EXT4_C2B(sbi,
267 percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
268 case attr_session_write_kbytes:
269 return session_write_kbytes_show(a, sbi, buf);
270 case attr_lifetime_write_kbytes:
271 return lifetime_write_kbytes_show(a, sbi, buf);
272 case attr_reserved_clusters:
273 return snprintf(buf, PAGE_SIZE, "%llu\n",
274 (unsigned long long)
275 atomic64_read(&sbi->s_resv_clusters));
276 case attr_inode_readahead:
277 case attr_pointer_ui:
278 if (!ptr)
279 return 0;
280 if (a->attr_ptr == ptr_ext4_super_block_offset)
281 return snprintf(buf, PAGE_SIZE, "%u\n",
282 le32_to_cpup(ptr));
283 else
284 return snprintf(buf, PAGE_SIZE, "%u\n",
285 *((unsigned int *) ptr));
286 case attr_pointer_atomic:
287 if (!ptr)
288 return 0;
289 return snprintf(buf, PAGE_SIZE, "%d\n",
290 atomic_read((atomic_t *) ptr));
291 case attr_feature:
292 return snprintf(buf, PAGE_SIZE, "supported\n");
293 }
294
295 return 0;
296 }
297
ext4_attr_store(struct kobject * kobj,struct attribute * attr,const char * buf,size_t len)298 static ssize_t ext4_attr_store(struct kobject *kobj,
299 struct attribute *attr,
300 const char *buf, size_t len)
301 {
302 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
303 s_kobj);
304 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
305 void *ptr = calc_ptr(a, sbi);
306 unsigned long t;
307 int ret;
308
309 switch (a->attr_id) {
310 case attr_reserved_clusters:
311 return reserved_clusters_store(a, sbi, buf, len);
312 case attr_pointer_ui:
313 if (!ptr)
314 return 0;
315 ret = kstrtoul(skip_spaces(buf), 0, &t);
316 if (ret)
317 return ret;
318 if (a->attr_ptr == ptr_ext4_super_block_offset)
319 *((__le32 *) ptr) = cpu_to_le32(t);
320 else
321 *((unsigned int *) ptr) = t;
322 return len;
323 case attr_inode_readahead:
324 return inode_readahead_blks_store(a, sbi, buf, len);
325 case attr_trigger_test_error:
326 return trigger_test_error(a, sbi, buf, len);
327 }
328 return 0;
329 }
330
ext4_sb_release(struct kobject * kobj)331 static void ext4_sb_release(struct kobject *kobj)
332 {
333 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
334 s_kobj);
335 complete(&sbi->s_kobj_unregister);
336 }
337
338 static const struct sysfs_ops ext4_attr_ops = {
339 .show = ext4_attr_show,
340 .store = ext4_attr_store,
341 };
342
343 static struct kobj_type ext4_sb_ktype = {
344 .default_attrs = ext4_attrs,
345 .sysfs_ops = &ext4_attr_ops,
346 .release = ext4_sb_release,
347 };
348
349 static struct kobj_type ext4_ktype = {
350 .sysfs_ops = &ext4_attr_ops,
351 };
352
353 static struct kset ext4_kset = {
354 .kobj = {.ktype = &ext4_ktype},
355 };
356
357 static struct kobj_type ext4_feat_ktype = {
358 .default_attrs = ext4_feat_attrs,
359 .sysfs_ops = &ext4_attr_ops,
360 };
361
362 static struct kobject ext4_feat = {
363 .kset = &ext4_kset,
364 };
365
366 #define PROC_FILE_SHOW_DEFN(name) \
367 static int name##_open(struct inode *inode, struct file *file) \
368 { \
369 return single_open(file, ext4_seq_##name##_show, PDE_DATA(inode)); \
370 } \
371 \
372 static const struct file_operations ext4_seq_##name##_fops = { \
373 .owner = THIS_MODULE, \
374 .open = name##_open, \
375 .read = seq_read, \
376 .llseek = seq_lseek, \
377 .release = single_release, \
378 }
379
380 #define PROC_FILE_LIST(name) \
381 { __stringify(name), &ext4_seq_##name##_fops }
382
383 PROC_FILE_SHOW_DEFN(es_shrinker_info);
384 PROC_FILE_SHOW_DEFN(options);
385
386 static struct ext4_proc_files {
387 const char *name;
388 const struct file_operations *fops;
389 } proc_files[] = {
390 PROC_FILE_LIST(options),
391 PROC_FILE_LIST(es_shrinker_info),
392 PROC_FILE_LIST(mb_groups),
393 { NULL, NULL },
394 };
395
ext4_register_sysfs(struct super_block * sb)396 int ext4_register_sysfs(struct super_block *sb)
397 {
398 struct ext4_sb_info *sbi = EXT4_SB(sb);
399 struct ext4_proc_files *p;
400 int err;
401
402 sbi->s_kobj.kset = &ext4_kset;
403 init_completion(&sbi->s_kobj_unregister);
404 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL,
405 "%s", sb->s_id);
406 if (err)
407 return err;
408
409 if (ext4_proc_root)
410 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
411
412 if (sbi->s_proc) {
413 for (p = proc_files; p->name; p++)
414 proc_create_data(p->name, S_IRUGO, sbi->s_proc,
415 p->fops, sb);
416 }
417 return 0;
418 }
419
ext4_unregister_sysfs(struct super_block * sb)420 void ext4_unregister_sysfs(struct super_block *sb)
421 {
422 struct ext4_sb_info *sbi = EXT4_SB(sb);
423 struct ext4_proc_files *p;
424
425 if (sbi->s_proc) {
426 for (p = proc_files; p->name; p++)
427 remove_proc_entry(p->name, sbi->s_proc);
428 remove_proc_entry(sb->s_id, ext4_proc_root);
429 }
430 kobject_del(&sbi->s_kobj);
431 }
432
ext4_init_sysfs(void)433 int __init ext4_init_sysfs(void)
434 {
435 int ret;
436
437 kobject_set_name(&ext4_kset.kobj, "ext4");
438 ext4_kset.kobj.parent = fs_kobj;
439 ret = kset_register(&ext4_kset);
440 if (ret)
441 return ret;
442
443 ret = kobject_init_and_add(&ext4_feat, &ext4_feat_ktype,
444 NULL, "features");
445 if (ret)
446 kset_unregister(&ext4_kset);
447 else
448 ext4_proc_root = proc_mkdir(proc_dirname, NULL);
449 return ret;
450 }
451
ext4_exit_sysfs(void)452 void ext4_exit_sysfs(void)
453 {
454 kobject_put(&ext4_feat);
455 kset_unregister(&ext4_kset);
456 remove_proc_entry(proc_dirname, NULL);
457 ext4_proc_root = NULL;
458 }
459
460