Merge tag 'leaks-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tobin...
[sfrench/cifs-2.6.git] / fs / ext4 / sysfs.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/sysfs.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Theodore Ts'o (tytso@mit.edu)
8  *
9  */
10
11 #include <linux/time.h>
12 #include <linux/fs.h>
13 #include <linux/seq_file.h>
14 #include <linux/slab.h>
15 #include <linux/proc_fs.h>
16
17 #include "ext4.h"
18 #include "ext4_jbd2.h"
19
20 typedef enum {
21         attr_noop,
22         attr_delayed_allocation_blocks,
23         attr_session_write_kbytes,
24         attr_lifetime_write_kbytes,
25         attr_reserved_clusters,
26         attr_inode_readahead,
27         attr_trigger_test_error,
28         attr_first_error_time,
29         attr_last_error_time,
30         attr_feature,
31         attr_pointer_ui,
32         attr_pointer_atomic,
33 } attr_id_t;
34
35 typedef enum {
36         ptr_explicit,
37         ptr_ext4_sb_info_offset,
38         ptr_ext4_super_block_offset,
39 } attr_ptr_t;
40
41 static const char proc_dirname[] = "fs/ext4";
42 static struct proc_dir_entry *ext4_proc_root;
43
44 struct ext4_attr {
45         struct attribute attr;
46         short attr_id;
47         short attr_ptr;
48         union {
49                 int offset;
50                 void *explicit_ptr;
51         } u;
52 };
53
54 static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
55 {
56         struct super_block *sb = sbi->s_buddy_cache->i_sb;
57
58         if (!sb->s_bdev->bd_part)
59                 return snprintf(buf, PAGE_SIZE, "0\n");
60         return snprintf(buf, PAGE_SIZE, "%lu\n",
61                         (part_stat_read(sb->s_bdev->bd_part,
62                                         sectors[STAT_WRITE]) -
63                          sbi->s_sectors_written_start) >> 1);
64 }
65
66 static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
67 {
68         struct super_block *sb = sbi->s_buddy_cache->i_sb;
69
70         if (!sb->s_bdev->bd_part)
71                 return snprintf(buf, PAGE_SIZE, "0\n");
72         return snprintf(buf, PAGE_SIZE, "%llu\n",
73                         (unsigned long long)(sbi->s_kbytes_written +
74                         ((part_stat_read(sb->s_bdev->bd_part,
75                                          sectors[STAT_WRITE]) -
76                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
77 }
78
79 static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi,
80                                           const char *buf, size_t count)
81 {
82         unsigned long t;
83         int ret;
84
85         ret = kstrtoul(skip_spaces(buf), 0, &t);
86         if (ret)
87                 return ret;
88
89         if (t && (!is_power_of_2(t) || t > 0x40000000))
90                 return -EINVAL;
91
92         sbi->s_inode_readahead_blks = t;
93         return count;
94 }
95
96 static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi,
97                                    const char *buf, size_t count)
98 {
99         unsigned long long val;
100         ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>
101                                  sbi->s_cluster_bits);
102         int ret;
103
104         ret = kstrtoull(skip_spaces(buf), 0, &val);
105         if (ret || val >= clusters)
106                 return -EINVAL;
107
108         atomic64_set(&sbi->s_resv_clusters, val);
109         return count;
110 }
111
112 static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
113                                   const char *buf, size_t count)
114 {
115         int len = count;
116
117         if (!capable(CAP_SYS_ADMIN))
118                 return -EPERM;
119
120         if (len && buf[len-1] == '\n')
121                 len--;
122
123         if (len)
124                 ext4_error(sbi->s_sb, "%.*s", len, buf);
125         return count;
126 }
127
128 #define EXT4_ATTR(_name,_mode,_id)                                      \
129 static struct ext4_attr ext4_attr_##_name = {                           \
130         .attr = {.name = __stringify(_name), .mode = _mode },           \
131         .attr_id = attr_##_id,                                          \
132 }
133
134 #define EXT4_ATTR_FUNC(_name,_mode)  EXT4_ATTR(_name,_mode,_name)
135
136 #define EXT4_ATTR_FEATURE(_name)   EXT4_ATTR(_name, 0444, feature)
137
138 #define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname)       \
139 static struct ext4_attr ext4_attr_##_name = {                   \
140         .attr = {.name = __stringify(_name), .mode = _mode },   \
141         .attr_id = attr_##_id,                                  \
142         .attr_ptr = ptr_##_struct##_offset,                     \
143         .u = {                                                  \
144                 .offset = offsetof(struct _struct, _elname),\
145         },                                                      \
146 }
147
148 #define EXT4_RO_ATTR_ES_UI(_name,_elname)                               \
149         EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)
150
151 #define EXT4_RW_ATTR_SBI_UI(_name,_elname)      \
152         EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)
153
154 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
155 static struct ext4_attr ext4_attr_##_name = {                   \
156         .attr = {.name = __stringify(_name), .mode = _mode },   \
157         .attr_id = attr_##_id,                                  \
158         .attr_ptr = ptr_explicit,                               \
159         .u = {                                                  \
160                 .explicit_ptr = _ptr,                           \
161         },                                                      \
162 }
163
164 #define ATTR_LIST(name) &ext4_attr_##name.attr
165
166 EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444);
167 EXT4_ATTR_FUNC(session_write_kbytes, 0444);
168 EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);
169 EXT4_ATTR_FUNC(reserved_clusters, 0644);
170
171 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
172                  ext4_sb_info, s_inode_readahead_blks);
173 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
174 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
175 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
176 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
177 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
178 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
179 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
180 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
181 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
182 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
183 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
184 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
185 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
186 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
187 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
188 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
189 EXT4_ATTR(first_error_time, 0444, first_error_time);
190 EXT4_ATTR(last_error_time, 0444, last_error_time);
191
192 static unsigned int old_bump_val = 128;
193 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
194
195 static struct attribute *ext4_attrs[] = {
196         ATTR_LIST(delayed_allocation_blocks),
197         ATTR_LIST(session_write_kbytes),
198         ATTR_LIST(lifetime_write_kbytes),
199         ATTR_LIST(reserved_clusters),
200         ATTR_LIST(inode_readahead_blks),
201         ATTR_LIST(inode_goal),
202         ATTR_LIST(mb_stats),
203         ATTR_LIST(mb_max_to_scan),
204         ATTR_LIST(mb_min_to_scan),
205         ATTR_LIST(mb_order2_req),
206         ATTR_LIST(mb_stream_req),
207         ATTR_LIST(mb_group_prealloc),
208         ATTR_LIST(max_writeback_mb_bump),
209         ATTR_LIST(extent_max_zeroout_kb),
210         ATTR_LIST(trigger_fs_error),
211         ATTR_LIST(err_ratelimit_interval_ms),
212         ATTR_LIST(err_ratelimit_burst),
213         ATTR_LIST(warning_ratelimit_interval_ms),
214         ATTR_LIST(warning_ratelimit_burst),
215         ATTR_LIST(msg_ratelimit_interval_ms),
216         ATTR_LIST(msg_ratelimit_burst),
217         ATTR_LIST(errors_count),
218         ATTR_LIST(first_error_time),
219         ATTR_LIST(last_error_time),
220         NULL,
221 };
222
223 /* Features this copy of ext4 supports */
224 EXT4_ATTR_FEATURE(lazy_itable_init);
225 EXT4_ATTR_FEATURE(batched_discard);
226 EXT4_ATTR_FEATURE(meta_bg_resize);
227 #ifdef CONFIG_EXT4_FS_ENCRYPTION
228 EXT4_ATTR_FEATURE(encryption);
229 #endif
230 EXT4_ATTR_FEATURE(metadata_csum_seed);
231
232 static struct attribute *ext4_feat_attrs[] = {
233         ATTR_LIST(lazy_itable_init),
234         ATTR_LIST(batched_discard),
235         ATTR_LIST(meta_bg_resize),
236 #ifdef CONFIG_EXT4_FS_ENCRYPTION
237         ATTR_LIST(encryption),
238 #endif
239         ATTR_LIST(metadata_csum_seed),
240         NULL,
241 };
242
243 static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
244 {
245         switch (a->attr_ptr) {
246         case ptr_explicit:
247                 return a->u.explicit_ptr;
248         case ptr_ext4_sb_info_offset:
249                 return (void *) (((char *) sbi) + a->u.offset);
250         case ptr_ext4_super_block_offset:
251                 return (void *) (((char *) sbi->s_es) + a->u.offset);
252         }
253         return NULL;
254 }
255
256 static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)
257 {
258         return snprintf(buf, PAGE_SIZE, "%lld",
259                         ((time64_t)hi << 32) + le32_to_cpu(lo));
260 }
261
262 #define print_tstamp(buf, es, tstamp) \
263         __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi)
264
265 static ssize_t ext4_attr_show(struct kobject *kobj,
266                               struct attribute *attr, char *buf)
267 {
268         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
269                                                 s_kobj);
270         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
271         void *ptr = calc_ptr(a, sbi);
272
273         switch (a->attr_id) {
274         case attr_delayed_allocation_blocks:
275                 return snprintf(buf, PAGE_SIZE, "%llu\n",
276                                 (s64) EXT4_C2B(sbi,
277                        percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
278         case attr_session_write_kbytes:
279                 return session_write_kbytes_show(sbi, buf);
280         case attr_lifetime_write_kbytes:
281                 return lifetime_write_kbytes_show(sbi, buf);
282         case attr_reserved_clusters:
283                 return snprintf(buf, PAGE_SIZE, "%llu\n",
284                                 (unsigned long long)
285                                 atomic64_read(&sbi->s_resv_clusters));
286         case attr_inode_readahead:
287         case attr_pointer_ui:
288                 if (!ptr)
289                         return 0;
290                 if (a->attr_ptr == ptr_ext4_super_block_offset)
291                         return snprintf(buf, PAGE_SIZE, "%u\n",
292                                         le32_to_cpup(ptr));
293                 else
294                         return snprintf(buf, PAGE_SIZE, "%u\n",
295                                         *((unsigned int *) ptr));
296         case attr_pointer_atomic:
297                 if (!ptr)
298                         return 0;
299                 return snprintf(buf, PAGE_SIZE, "%d\n",
300                                 atomic_read((atomic_t *) ptr));
301         case attr_feature:
302                 return snprintf(buf, PAGE_SIZE, "supported\n");
303         case attr_first_error_time:
304                 return print_tstamp(buf, sbi->s_es, s_first_error_time);
305         case attr_last_error_time:
306                 return print_tstamp(buf, sbi->s_es, s_last_error_time);
307         }
308
309         return 0;
310 }
311
312 static ssize_t ext4_attr_store(struct kobject *kobj,
313                                struct attribute *attr,
314                                const char *buf, size_t len)
315 {
316         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
317                                                 s_kobj);
318         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
319         void *ptr = calc_ptr(a, sbi);
320         unsigned long t;
321         int ret;
322
323         switch (a->attr_id) {
324         case attr_reserved_clusters:
325                 return reserved_clusters_store(sbi, buf, len);
326         case attr_pointer_ui:
327                 if (!ptr)
328                         return 0;
329                 ret = kstrtoul(skip_spaces(buf), 0, &t);
330                 if (ret)
331                         return ret;
332                 if (a->attr_ptr == ptr_ext4_super_block_offset)
333                         *((__le32 *) ptr) = cpu_to_le32(t);
334                 else
335                         *((unsigned int *) ptr) = t;
336                 return len;
337         case attr_inode_readahead:
338                 return inode_readahead_blks_store(sbi, buf, len);
339         case attr_trigger_test_error:
340                 return trigger_test_error(sbi, buf, len);
341         }
342         return 0;
343 }
344
345 static void ext4_sb_release(struct kobject *kobj)
346 {
347         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
348                                                 s_kobj);
349         complete(&sbi->s_kobj_unregister);
350 }
351
352 static const struct sysfs_ops ext4_attr_ops = {
353         .show   = ext4_attr_show,
354         .store  = ext4_attr_store,
355 };
356
357 static struct kobj_type ext4_sb_ktype = {
358         .default_attrs  = ext4_attrs,
359         .sysfs_ops      = &ext4_attr_ops,
360         .release        = ext4_sb_release,
361 };
362
363 static struct kobj_type ext4_feat_ktype = {
364         .default_attrs  = ext4_feat_attrs,
365         .sysfs_ops      = &ext4_attr_ops,
366         .release        = (void (*)(struct kobject *))kfree,
367 };
368
369 static struct kobject *ext4_root;
370
371 static struct kobject *ext4_feat;
372
373 int ext4_register_sysfs(struct super_block *sb)
374 {
375         struct ext4_sb_info *sbi = EXT4_SB(sb);
376         int err;
377
378         init_completion(&sbi->s_kobj_unregister);
379         err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root,
380                                    "%s", sb->s_id);
381         if (err) {
382                 kobject_put(&sbi->s_kobj);
383                 wait_for_completion(&sbi->s_kobj_unregister);
384                 return err;
385         }
386
387         if (ext4_proc_root)
388                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
389         if (sbi->s_proc) {
390                 proc_create_single_data("options", S_IRUGO, sbi->s_proc,
391                                 ext4_seq_options_show, sb);
392                 proc_create_single_data("es_shrinker_info", S_IRUGO,
393                                 sbi->s_proc, ext4_seq_es_shrinker_info_show,
394                                 sb);
395                 proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc,
396                                 &ext4_mb_seq_groups_ops, sb);
397         }
398         return 0;
399 }
400
401 void ext4_unregister_sysfs(struct super_block *sb)
402 {
403         struct ext4_sb_info *sbi = EXT4_SB(sb);
404
405         if (sbi->s_proc)
406                 remove_proc_subtree(sb->s_id, ext4_proc_root);
407         kobject_del(&sbi->s_kobj);
408 }
409
410 int __init ext4_init_sysfs(void)
411 {
412         int ret;
413
414         ext4_root = kobject_create_and_add("ext4", fs_kobj);
415         if (!ext4_root)
416                 return -ENOMEM;
417
418         ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
419         if (!ext4_feat) {
420                 ret = -ENOMEM;
421                 goto root_err;
422         }
423
424         ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
425                                    ext4_root, "features");
426         if (ret)
427                 goto feat_err;
428
429         ext4_proc_root = proc_mkdir(proc_dirname, NULL);
430         return ret;
431
432 feat_err:
433         kobject_put(ext4_feat);
434         ext4_feat = NULL;
435 root_err:
436         kobject_put(ext4_root);
437         ext4_root = NULL;
438         return ret;
439 }
440
441 void ext4_exit_sysfs(void)
442 {
443         kobject_put(ext4_feat);
444         ext4_feat = NULL;
445         kobject_put(ext4_root);
446         ext4_root = NULL;
447         remove_proc_entry(proc_dirname, NULL);
448         ext4_proc_root = NULL;
449 }
450