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>
28 #include "transaction.h"
31 static inline struct btrfs_fs_info
*to_fs_info(struct kobject
*kobj
);
33 static u64
get_features(struct btrfs_fs_info
*fs_info
,
34 enum btrfs_feature_set set
)
36 struct btrfs_super_block
*disk_super
= fs_info
->super_copy
;
37 if (set
== FEAT_COMPAT
)
38 return btrfs_super_compat_flags(disk_super
);
39 else if (set
== FEAT_COMPAT_RO
)
40 return btrfs_super_compat_ro_flags(disk_super
);
42 return btrfs_super_incompat_flags(disk_super
);
45 static ssize_t
btrfs_feature_attr_show(struct kobject
*kobj
,
46 struct kobj_attribute
*a
, char *buf
)
49 struct btrfs_fs_info
*fs_info
= to_fs_info(kobj
);
51 struct btrfs_feature_attr
*fa
= to_btrfs_feature_attr(a
);
52 u64 features
= get_features(fs_info
, fa
->feature_set
);
53 if (features
& fa
->feature_bit
)
57 return snprintf(buf
, PAGE_SIZE
, "%d\n", val
);
60 static umode_t
btrfs_feature_visible(struct kobject
*kobj
,
61 struct attribute
*attr
, int unused
)
63 struct btrfs_fs_info
*fs_info
= to_fs_info(kobj
);
64 umode_t mode
= attr
->mode
;
67 struct btrfs_feature_attr
*fa
;
70 fa
= attr_to_btrfs_feature_attr(attr
);
71 features
= get_features(fs_info
, fa
->feature_set
);
73 if (!(features
& fa
->feature_bit
))
80 BTRFS_FEAT_ATTR_INCOMPAT(mixed_backref
, MIXED_BACKREF
);
81 BTRFS_FEAT_ATTR_INCOMPAT(default_subvol
, DEFAULT_SUBVOL
);
82 BTRFS_FEAT_ATTR_INCOMPAT(mixed_groups
, MIXED_GROUPS
);
83 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzo
, COMPRESS_LZO
);
84 BTRFS_FEAT_ATTR_INCOMPAT(compress_lzov2
, COMPRESS_LZOv2
);
85 BTRFS_FEAT_ATTR_INCOMPAT(big_metadata
, BIG_METADATA
);
86 BTRFS_FEAT_ATTR_INCOMPAT(extended_iref
, EXTENDED_IREF
);
87 BTRFS_FEAT_ATTR_INCOMPAT(raid56
, RAID56
);
88 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata
, SKINNY_METADATA
);
90 static struct attribute
*btrfs_supported_feature_attrs
[] = {
91 BTRFS_FEAT_ATTR_PTR(mixed_backref
),
92 BTRFS_FEAT_ATTR_PTR(default_subvol
),
93 BTRFS_FEAT_ATTR_PTR(mixed_groups
),
94 BTRFS_FEAT_ATTR_PTR(compress_lzo
),
95 BTRFS_FEAT_ATTR_PTR(compress_lzov2
),
96 BTRFS_FEAT_ATTR_PTR(big_metadata
),
97 BTRFS_FEAT_ATTR_PTR(extended_iref
),
98 BTRFS_FEAT_ATTR_PTR(raid56
),
99 BTRFS_FEAT_ATTR_PTR(skinny_metadata
),
103 static const struct attribute_group btrfs_feature_attr_group
= {
105 .is_visible
= btrfs_feature_visible
,
106 .attrs
= btrfs_supported_feature_attrs
,
109 static void btrfs_release_super_kobj(struct kobject
*kobj
)
111 struct btrfs_fs_info
*fs_info
= to_fs_info(kobj
);
112 complete(&fs_info
->kobj_unregister
);
115 static struct kobj_type btrfs_ktype
= {
116 .sysfs_ops
= &kobj_sysfs_ops
,
117 .release
= btrfs_release_super_kobj
,
120 static inline struct btrfs_fs_info
*to_fs_info(struct kobject
*kobj
)
122 if (kobj
->ktype
!= &btrfs_ktype
)
124 return container_of(kobj
, struct btrfs_fs_info
, super_kobj
);
127 void btrfs_sysfs_remove_one(struct btrfs_fs_info
*fs_info
)
129 kobject_del(&fs_info
->super_kobj
);
130 kobject_put(&fs_info
->super_kobj
);
131 wait_for_completion(&fs_info
->kobj_unregister
);
134 /* /sys/fs/btrfs/ entry */
135 static struct kset
*btrfs_kset
;
137 int btrfs_sysfs_add_one(struct btrfs_fs_info
*fs_info
)
141 init_completion(&fs_info
->kobj_unregister
);
142 fs_info
->super_kobj
.kset
= btrfs_kset
;
143 error
= kobject_init_and_add(&fs_info
->super_kobj
, &btrfs_ktype
, NULL
,
144 "%pU", fs_info
->fsid
);
146 error
= sysfs_create_group(&fs_info
->super_kobj
,
147 &btrfs_feature_attr_group
);
149 btrfs_sysfs_remove_one(fs_info
);
153 int btrfs_init_sysfs(void)
156 btrfs_kset
= kset_create_and_add("btrfs", NULL
, fs_kobj
);
160 ret
= sysfs_create_group(&btrfs_kset
->kobj
, &btrfs_feature_attr_group
);
162 kset_unregister(btrfs_kset
);
169 void btrfs_exit_sysfs(void)
171 sysfs_remove_group(&btrfs_kset
->kobj
, &btrfs_feature_attr_group
);
172 kset_unregister(btrfs_kset
);