2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
20 #include <linux/slab.h>
21 #include <linux/spinlock.h>
22 #include <linux/completion.h>
23 #include <linux/buffer_head.h>
24 #include <linux/kobject.h>
25 #include <linux/bug.h>
26 #include <linux/genhd.h>
30 #include "transaction.h"
34 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj);
36 static u64 get_features(struct btrfs_fs_info *fs_info,
37 enum btrfs_feature_set set)
39 struct btrfs_super_block *disk_super = fs_info->super_copy;
40 if (set == FEAT_COMPAT)
41 return btrfs_super_compat_flags(disk_super);
42 else if (set == FEAT_COMPAT_RO)
43 return btrfs_super_compat_ro_flags(disk_super);
45 return btrfs_super_incompat_flags(disk_super);
48 static void set_features(struct btrfs_fs_info *fs_info,
49 enum btrfs_feature_set set, u64 features)
51 struct btrfs_super_block *disk_super = fs_info->super_copy;
52 if (set == FEAT_COMPAT)
53 btrfs_set_super_compat_flags(disk_super, features);
54 else if (set == FEAT_COMPAT_RO)
55 btrfs_set_super_compat_ro_flags(disk_super, features);
57 btrfs_set_super_incompat_flags(disk_super, features);
60 static int can_modify_feature(struct btrfs_feature_attr *fa)
64 switch (fa->feature_set) {
66 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
67 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
70 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
71 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
74 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
75 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
81 if (set & fa->feature_bit)
83 if (clear & fa->feature_bit)
89 static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
90 struct kobj_attribute *a, char *buf)
93 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
94 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
96 u64 features = get_features(fs_info, fa->feature_set);
97 if (features & fa->feature_bit)
100 val = can_modify_feature(fa);
102 return snprintf(buf, PAGE_SIZE, "%d\n", val);
105 static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
106 struct kobj_attribute *a,
107 const char *buf, size_t count)
109 struct btrfs_fs_info *fs_info;
110 struct btrfs_feature_attr *fa = to_btrfs_feature_attr(a);
111 struct btrfs_trans_handle *trans;
112 u64 features, set, clear;
116 fs_info = to_fs_info(kobj);
120 ret = kstrtoul(skip_spaces(buf), 0, &val);
124 if (fa->feature_set == FEAT_COMPAT) {
125 set = BTRFS_FEATURE_COMPAT_SAFE_SET;
126 clear = BTRFS_FEATURE_COMPAT_SAFE_CLEAR;
127 } else if (fa->feature_set == FEAT_COMPAT_RO) {
128 set = BTRFS_FEATURE_COMPAT_RO_SAFE_SET;
129 clear = BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR;
131 set = BTRFS_FEATURE_INCOMPAT_SAFE_SET;
132 clear = BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR;
135 features = get_features(fs_info, fa->feature_set);
138 if ((val && (features & fa->feature_bit)) ||
139 (!val && !(features & fa->feature_bit)))
142 if ((val && !(set & fa->feature_bit)) ||
143 (!val && !(clear & fa->feature_bit))) {
145 "%sabling feature %s on mounted fs is not supported.",
146 val ? "En" : "Dis", fa->kobj_attr.attr.name);
150 btrfs_info(fs_info, "%s %s feature flag",
151 val ? "Setting" : "Clearing", fa->kobj_attr.attr.name);
153 trans = btrfs_start_transaction(fs_info->fs_root, 1);
155 return PTR_ERR(trans);
157 spin_lock(&fs_info->super_lock);
158 features = get_features(fs_info, fa->feature_set);
160 features |= fa->feature_bit;
162 features &= ~fa->feature_bit;
163 set_features(fs_info, fa->feature_set, features);
164 spin_unlock(&fs_info->super_lock);
166 ret = btrfs_commit_transaction(trans, fs_info->fs_root);
173 static umode_t btrfs_feature_visible(struct kobject *kobj,
174 struct attribute *attr, int unused)
176 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
177 umode_t mode = attr->mode;
180 struct btrfs_feature_attr *fa;
183 fa = attr_to_btrfs_feature_attr(attr);
184 features = get_features(fs_info, fa->feature_set);
186 if (can_modify_feature(fa))
188 else if (!(features & fa->feature_bit))
195 BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref, MIXED_BACKREF);
196 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol, DEFAULT_SUBVOL);
197 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups, MIXED_GROUPS);
198 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo, COMPRESS_LZO);
199 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzov2, COMPRESS_LZOv2);
200 BTRFS_FEAT_ATTR_INCOMPAT(big_metadata, BIG_METADATA);
201 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
202 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
203 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
205 static struct attribute *btrfs_supported_feature_attrs[] = {
206 BTRFS_FEAT_ATTR_PTR(mixed_backref),
207 BTRFS_FEAT_ATTR_PTR(default_subvol),
208 BTRFS_FEAT_ATTR_PTR(mixed_groups),
209 BTRFS_FEAT_ATTR_PTR(compress_lzo),
210 BTRFS_FEAT_ATTR_PTR(compress_lzov2),
211 BTRFS_FEAT_ATTR_PTR(big_metadata),
212 BTRFS_FEAT_ATTR_PTR(extended_iref),
213 BTRFS_FEAT_ATTR_PTR(raid56),
214 BTRFS_FEAT_ATTR_PTR(skinny_metadata),
218 static const struct attribute_group btrfs_feature_attr_group = {
220 .is_visible = btrfs_feature_visible,
221 .attrs = btrfs_supported_feature_attrs,
224 static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
232 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
235 static ssize_t global_rsv_size_show(struct kobject *kobj,
236 struct kobj_attribute *ka, char *buf)
238 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
239 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
240 return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
242 BTRFS_ATTR(global_rsv_size, 0444, global_rsv_size_show);
244 static ssize_t global_rsv_reserved_show(struct kobject *kobj,
245 struct kobj_attribute *a, char *buf)
247 struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
248 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
249 return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
251 BTRFS_ATTR(global_rsv_reserved, 0444, global_rsv_reserved_show);
253 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
255 static ssize_t raid_bytes_show(struct kobject *kobj,
256 struct kobj_attribute *attr, char *buf);
257 BTRFS_RAID_ATTR(total_bytes, raid_bytes_show);
258 BTRFS_RAID_ATTR(used_bytes, raid_bytes_show);
260 static ssize_t raid_bytes_show(struct kobject *kobj,
261 struct kobj_attribute *attr, char *buf)
264 struct btrfs_space_info *sinfo = to_space_info(kobj->parent);
265 struct btrfs_block_group_cache *block_group;
266 int index = kobj - sinfo->block_group_kobjs;
269 down_read(&sinfo->groups_sem);
270 list_for_each_entry(block_group, &sinfo->block_groups[index], list) {
271 if (&attr->attr == BTRFS_RAID_ATTR_PTR(total_bytes))
272 val += block_group->key.offset;
274 val += btrfs_block_group_used(&block_group->item);
276 up_read(&sinfo->groups_sem);
277 return snprintf(buf, PAGE_SIZE, "%llu\n", val);
280 static struct attribute *raid_attributes[] = {
281 BTRFS_RAID_ATTR_PTR(total_bytes),
282 BTRFS_RAID_ATTR_PTR(used_bytes),
286 static void release_raid_kobj(struct kobject *kobj)
288 kobject_put(kobj->parent);
291 struct kobj_type btrfs_raid_ktype = {
292 .sysfs_ops = &kobj_sysfs_ops,
293 .release = release_raid_kobj,
294 .default_attrs = raid_attributes,
297 #define SPACE_INFO_ATTR(field) \
298 static ssize_t btrfs_space_info_show_##field(struct kobject *kobj, \
299 struct kobj_attribute *a, \
302 struct btrfs_space_info *sinfo = to_space_info(kobj); \
303 return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf); \
305 BTRFS_ATTR(field, 0444, btrfs_space_info_show_##field)
307 static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
308 struct kobj_attribute *a,
311 struct btrfs_space_info *sinfo = to_space_info(kobj);
312 s64 val = percpu_counter_sum(&sinfo->total_bytes_pinned);
313 return snprintf(buf, PAGE_SIZE, "%lld\n", val);
316 SPACE_INFO_ATTR(flags);
317 SPACE_INFO_ATTR(total_bytes);
318 SPACE_INFO_ATTR(bytes_used);
319 SPACE_INFO_ATTR(bytes_pinned);
320 SPACE_INFO_ATTR(bytes_reserved);
321 SPACE_INFO_ATTR(bytes_may_use);
322 SPACE_INFO_ATTR(disk_used);
323 SPACE_INFO_ATTR(disk_total);
324 BTRFS_ATTR(total_bytes_pinned, 0444, btrfs_space_info_show_total_bytes_pinned);
326 static struct attribute *space_info_attrs[] = {
327 BTRFS_ATTR_PTR(flags),
328 BTRFS_ATTR_PTR(total_bytes),
329 BTRFS_ATTR_PTR(bytes_used),
330 BTRFS_ATTR_PTR(bytes_pinned),
331 BTRFS_ATTR_PTR(bytes_reserved),
332 BTRFS_ATTR_PTR(bytes_may_use),
333 BTRFS_ATTR_PTR(disk_used),
334 BTRFS_ATTR_PTR(disk_total),
335 BTRFS_ATTR_PTR(total_bytes_pinned),
339 static void space_info_release(struct kobject *kobj)
341 struct btrfs_space_info *sinfo = to_space_info(kobj);
342 percpu_counter_destroy(&sinfo->total_bytes_pinned);
346 struct kobj_type space_info_ktype = {
347 .sysfs_ops = &kobj_sysfs_ops,
348 .release = space_info_release,
349 .default_attrs = space_info_attrs,
352 static const struct attribute *allocation_attrs[] = {
353 BTRFS_ATTR_PTR(global_rsv_reserved),
354 BTRFS_ATTR_PTR(global_rsv_size),
358 static ssize_t btrfs_label_show(struct kobject *kobj,
359 struct kobj_attribute *a, char *buf)
361 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
362 return snprintf(buf, PAGE_SIZE, "%s\n", fs_info->super_copy->label);
365 static ssize_t btrfs_label_store(struct kobject *kobj,
366 struct kobj_attribute *a,
367 const char *buf, size_t len)
369 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
370 struct btrfs_trans_handle *trans;
371 struct btrfs_root *root = fs_info->fs_root;
374 if (len >= BTRFS_LABEL_SIZE) {
375 pr_err("btrfs: unable to set label with more than %d bytes\n",
376 BTRFS_LABEL_SIZE - 1);
380 trans = btrfs_start_transaction(root, 0);
382 return PTR_ERR(trans);
384 spin_lock(&root->fs_info->super_lock);
385 strcpy(fs_info->super_copy->label, buf);
386 spin_unlock(&root->fs_info->super_lock);
387 ret = btrfs_commit_transaction(trans, root);
394 BTRFS_ATTR_RW(label, 0644, btrfs_label_show, btrfs_label_store);
396 static struct attribute *btrfs_attrs[] = {
397 BTRFS_ATTR_PTR(label),
401 static void btrfs_release_super_kobj(struct kobject *kobj)
403 struct btrfs_fs_info *fs_info = to_fs_info(kobj);
404 complete(&fs_info->kobj_unregister);
407 static struct kobj_type btrfs_ktype = {
408 .sysfs_ops = &kobj_sysfs_ops,
409 .release = btrfs_release_super_kobj,
410 .default_attrs = btrfs_attrs,
413 static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
415 if (kobj->ktype != &btrfs_ktype)
417 return container_of(kobj, struct btrfs_fs_info, super_kobj);
420 void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info)
422 sysfs_remove_files(fs_info->space_info_kobj, allocation_attrs);
423 kobject_del(fs_info->device_dir_kobj);
424 kobject_put(fs_info->device_dir_kobj);
425 kobject_del(fs_info->space_info_kobj);
426 kobject_put(fs_info->space_info_kobj);
427 kobject_del(&fs_info->super_kobj);
428 kobject_put(&fs_info->super_kobj);
429 wait_for_completion(&fs_info->kobj_unregister);
432 const char * const btrfs_feature_set_names[3] = {
433 [FEAT_COMPAT] = "compat",
434 [FEAT_COMPAT_RO] = "compat_ro",
435 [FEAT_INCOMPAT] = "incompat",
438 #define NUM_FEATURE_BITS 64
439 static char btrfs_unknown_feature_names[3][NUM_FEATURE_BITS][13];
440 static struct btrfs_feature_attr btrfs_feature_attrs[3][NUM_FEATURE_BITS];
442 char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags)
444 size_t bufsize = 4096; /* safe max, 64 names * 64 bytes */
449 str = kmalloc(bufsize, GFP_KERNEL);
453 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
456 if (!(flags & (1ULL << i)))
459 name = btrfs_feature_attrs[set][i].kobj_attr.attr.name;
460 len += snprintf(str + len, bufsize - len, "%s%s",
461 len ? "," : "", name);
467 static void init_feature_attrs(void)
469 struct btrfs_feature_attr *fa;
472 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names) !=
473 ARRAY_SIZE(btrfs_feature_attrs));
474 BUILD_BUG_ON(ARRAY_SIZE(btrfs_unknown_feature_names[0]) !=
475 ARRAY_SIZE(btrfs_feature_attrs[0]));
477 memset(btrfs_feature_attrs, 0, sizeof(btrfs_feature_attrs));
478 memset(btrfs_unknown_feature_names, 0,
479 sizeof(btrfs_unknown_feature_names));
481 for (i = 0; btrfs_supported_feature_attrs[i]; i++) {
482 struct btrfs_feature_attr *sfa;
483 struct attribute *a = btrfs_supported_feature_attrs[i];
485 sfa = attr_to_btrfs_feature_attr(a);
486 bit = ilog2(sfa->feature_bit);
487 fa = &btrfs_feature_attrs[sfa->feature_set][bit];
489 fa->kobj_attr.attr.name = sfa->kobj_attr.attr.name;
492 for (set = 0; set < FEAT_MAX; set++) {
493 for (i = 0; i < ARRAY_SIZE(btrfs_feature_attrs[set]); i++) {
494 char *name = btrfs_unknown_feature_names[set][i];
495 fa = &btrfs_feature_attrs[set][i];
497 if (fa->kobj_attr.attr.name)
500 snprintf(name, 13, "%s:%u",
501 btrfs_feature_set_names[set], i);
503 fa->kobj_attr.attr.name = name;
504 fa->kobj_attr.attr.mode = S_IRUGO;
505 fa->feature_set = set;
506 fa->feature_bit = 1ULL << i;
511 static u64 supported_feature_masks[3] = {
512 [FEAT_COMPAT] = BTRFS_FEATURE_COMPAT_SUPP,
513 [FEAT_COMPAT_RO] = BTRFS_FEATURE_COMPAT_RO_SUPP,
514 [FEAT_INCOMPAT] = BTRFS_FEATURE_INCOMPAT_SUPP,
517 static int add_unknown_feature_attrs(struct btrfs_fs_info *fs_info)
521 for (set = 0; set < FEAT_MAX; set++) {
522 int i, count, ret, index = 0;
523 struct attribute **attrs;
524 struct attribute_group agroup = {
527 u64 features = get_features(fs_info, set);
528 features &= ~supported_feature_masks[set];
530 count = hweight64(features);
535 attrs = kcalloc(count + 1, sizeof(void *), GFP_KERNEL);
537 for (i = 0; i < NUM_FEATURE_BITS; i++) {
538 struct btrfs_feature_attr *fa;
540 if (!(features & (1ULL << i)))
543 fa = &btrfs_feature_attrs[set][i];
544 attrs[index++] = &fa->kobj_attr.attr;
548 agroup.attrs = attrs;
550 ret = sysfs_merge_group(&fs_info->super_kobj, &agroup);
558 static int add_device_membership(struct btrfs_fs_info *fs_info)
561 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
562 struct btrfs_device *dev;
564 fs_info->device_dir_kobj = kobject_create_and_add("devices",
565 &fs_info->super_kobj);
566 if (!fs_info->device_dir_kobj)
569 list_for_each_entry(dev, &fs_devices->devices, dev_list) {
570 struct hd_struct *disk = dev->bdev->bd_part;
571 struct kobject *disk_kobj = &part_to_dev(disk)->kobj;
573 error = sysfs_create_link(fs_info->device_dir_kobj,
574 disk_kobj, disk_kobj->name);
582 /* /sys/fs/btrfs/ entry */
583 static struct kset *btrfs_kset;
585 int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info)
589 init_completion(&fs_info->kobj_unregister);
590 fs_info->super_kobj.kset = btrfs_kset;
591 error = kobject_init_and_add(&fs_info->super_kobj, &btrfs_ktype, NULL,
592 "%pU", fs_info->fsid);
594 error = sysfs_create_group(&fs_info->super_kobj,
595 &btrfs_feature_attr_group);
599 error = add_unknown_feature_attrs(fs_info);
603 error = add_device_membership(fs_info);
607 fs_info->space_info_kobj = kobject_create_and_add("allocation",
608 &fs_info->super_kobj);
609 if (!fs_info->space_info_kobj) {
614 error = sysfs_create_files(fs_info->space_info_kobj, allocation_attrs);
620 btrfs_sysfs_remove_one(fs_info);
624 int btrfs_init_sysfs(void)
627 btrfs_kset = kset_create_and_add("btrfs", NULL, fs_kobj);
631 init_feature_attrs();
633 ret = sysfs_create_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
635 kset_unregister(btrfs_kset);
642 void btrfs_exit_sysfs(void)
644 sysfs_remove_group(&btrfs_kset->kobj, &btrfs_feature_attr_group);
645 kset_unregister(btrfs_kset);