diff options
Diffstat (limited to 'fs/btrfs')
-rw-r--r-- | fs/btrfs/Makefile | 2 | ||||
-rw-r--r-- | fs/btrfs/compat.h | 17 | ||||
-rw-r--r-- | fs/btrfs/export.c | 208 | ||||
-rw-r--r-- | fs/btrfs/export.h | 19 | ||||
-rw-r--r-- | fs/btrfs/super.c | 2 |
5 files changed, 247 insertions, 1 deletions
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index a4b38177abdb..75f8818cbfee 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile | |||
@@ -7,7 +7,7 @@ btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ | |||
7 | transaction.o bit-radix.o inode.o file.o tree-defrag.o \ | 7 | transaction.o bit-radix.o inode.o file.o tree-defrag.o \ |
8 | extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \ | 8 | extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \ |
9 | extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \ | 9 | extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \ |
10 | ref-cache.o | 10 | ref-cache.o export.o |
11 | 11 | ||
12 | btrfs-$(CONFIG_FS_POSIX_ACL) += acl.o | 12 | btrfs-$(CONFIG_FS_POSIX_ACL) += acl.o |
13 | else | 13 | else |
diff --git a/fs/btrfs/compat.h b/fs/btrfs/compat.h index b3349a66999d..d45fb37887bc 100644 --- a/fs/btrfs/compat.h +++ b/fs/btrfs/compat.h | |||
@@ -5,6 +5,23 @@ | |||
5 | #define trylock_page(page) (!TestSetPageLocked(page)) | 5 | #define trylock_page(page) (!TestSetPageLocked(page)) |
6 | #endif | 6 | #endif |
7 | 7 | ||
8 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,27) | ||
9 | static inline struct dentry *d_obtain_alias(struct inode *inode) | ||
10 | { | ||
11 | struct dentry *d; | ||
12 | |||
13 | if (!inode) | ||
14 | return NULL; | ||
15 | if (IS_ERR(inode)) | ||
16 | return ERR_CAST(inode); | ||
17 | |||
18 | d = d_alloc_anon(inode); | ||
19 | if (!d) | ||
20 | iput(inode); | ||
21 | return d; | ||
22 | } | ||
23 | #endif | ||
24 | |||
8 | /* | 25 | /* |
9 | * Even if AppArmor isn't enabled, it still has different prototypes. | 26 | * Even if AppArmor isn't enabled, it still has different prototypes. |
10 | * Add more distro/version pairs here to declare which has AppArmor applied. | 27 | * Add more distro/version pairs here to declare which has AppArmor applied. |
diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c new file mode 100644 index 000000000000..797b4cbc3786 --- /dev/null +++ b/fs/btrfs/export.c | |||
@@ -0,0 +1,208 @@ | |||
1 | #include <linux/fs.h> | ||
2 | #include <linux/types.h> | ||
3 | #include "ctree.h" | ||
4 | #include "disk-io.h" | ||
5 | #include "btrfs_inode.h" | ||
6 | #include "print-tree.h" | ||
7 | #include "export.h" | ||
8 | #include "compat.h" | ||
9 | |||
10 | #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28) | ||
11 | #define FILEID_BTRFS_WITHOUT_PARENT 0x4d | ||
12 | #define FILEID_BTRFS_WITH_PARENT 0x4e | ||
13 | #define FILEID_BTRFS_WITH_PARENT_ROOT 0x4f | ||
14 | #endif | ||
15 | |||
16 | #define BTRFS_FID_SIZE_NON_CONNECTABLE (offsetof(struct btrfs_fid, parent_objectid)/4) | ||
17 | #define BTRFS_FID_SIZE_CONNECTABLE (offsetof(struct btrfs_fid, parent_root_objectid)/4) | ||
18 | #define BTRFS_FID_SIZE_CONNECTABLE_ROOT (sizeof(struct btrfs_fid)/4) | ||
19 | |||
20 | static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len, | ||
21 | int connectable) | ||
22 | { | ||
23 | struct btrfs_fid *fid = (struct btrfs_fid *)fh; | ||
24 | struct inode *inode = dentry->d_inode; | ||
25 | int len = *max_len; | ||
26 | int type; | ||
27 | |||
28 | if ((len < BTRFS_FID_SIZE_NON_CONNECTABLE) || | ||
29 | (connectable && len < BTRFS_FID_SIZE_CONNECTABLE)) | ||
30 | return 255; | ||
31 | |||
32 | len = BTRFS_FID_SIZE_NON_CONNECTABLE; | ||
33 | type = FILEID_BTRFS_WITHOUT_PARENT; | ||
34 | |||
35 | fid->objectid = BTRFS_I(inode)->location.objectid; | ||
36 | fid->root_objectid = BTRFS_I(inode)->root->objectid; | ||
37 | fid->gen = inode->i_generation; | ||
38 | |||
39 | if (connectable && !S_ISDIR(inode->i_mode)) { | ||
40 | struct inode *parent; | ||
41 | u64 parent_root_id; | ||
42 | |||
43 | spin_lock(&dentry->d_lock); | ||
44 | |||
45 | parent = dentry->d_parent->d_inode; | ||
46 | fid->parent_objectid = BTRFS_I(parent)->location.objectid; | ||
47 | fid->parent_gen = parent->i_generation; | ||
48 | parent_root_id = BTRFS_I(parent)->root->objectid; | ||
49 | |||
50 | spin_unlock(&dentry->d_lock); | ||
51 | |||
52 | if (parent_root_id != fid->root_objectid) { | ||
53 | fid->parent_root_objectid = parent_root_id; | ||
54 | len = BTRFS_FID_SIZE_CONNECTABLE_ROOT; | ||
55 | type = FILEID_BTRFS_WITH_PARENT_ROOT; | ||
56 | } else { | ||
57 | len = BTRFS_FID_SIZE_CONNECTABLE; | ||
58 | type = FILEID_BTRFS_WITH_PARENT; | ||
59 | } | ||
60 | } | ||
61 | |||
62 | *max_len = len; | ||
63 | return type; | ||
64 | } | ||
65 | |||
66 | static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid, | ||
67 | u64 root_objectid, u32 generation) | ||
68 | { | ||
69 | struct btrfs_root *root; | ||
70 | struct inode *inode; | ||
71 | struct dentry *result; | ||
72 | struct btrfs_key key; | ||
73 | |||
74 | key.objectid = objectid; | ||
75 | btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); | ||
76 | key.offset = 0; | ||
77 | |||
78 | root = btrfs_lookup_fs_root(btrfs_sb(sb)->fs_info, root_objectid); | ||
79 | inode = btrfs_iget(sb, &key, root, NULL); | ||
80 | if (IS_ERR(inode)) | ||
81 | return (void *)inode; | ||
82 | |||
83 | if (generation != inode->i_generation) { | ||
84 | iput(inode); | ||
85 | return ERR_PTR(-ESTALE); | ||
86 | } | ||
87 | |||
88 | result = d_obtain_alias(inode); | ||
89 | if (!result) | ||
90 | return ERR_PTR(-ENOMEM); | ||
91 | |||
92 | return result; | ||
93 | } | ||
94 | |||
95 | static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh, | ||
96 | int fh_len, int fh_type) | ||
97 | { | ||
98 | struct btrfs_fid *fid = (struct btrfs_fid *) fh; | ||
99 | u64 objectid, root_objectid; | ||
100 | u32 generation; | ||
101 | |||
102 | if (fh_type == FILEID_BTRFS_WITH_PARENT) { | ||
103 | if (fh_len != BTRFS_FID_SIZE_CONNECTABLE) | ||
104 | return NULL; | ||
105 | root_objectid = fid->root_objectid; | ||
106 | } else if (fh_type == FILEID_BTRFS_WITH_PARENT_ROOT) { | ||
107 | if (fh_len != BTRFS_FID_SIZE_CONNECTABLE_ROOT) | ||
108 | return NULL; | ||
109 | root_objectid = fid->parent_root_objectid; | ||
110 | } else | ||
111 | return NULL; | ||
112 | |||
113 | objectid = fid->parent_objectid; | ||
114 | generation = fid->parent_gen; | ||
115 | |||
116 | return btrfs_get_dentry(sb, objectid, root_objectid, generation); | ||
117 | } | ||
118 | |||
119 | static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh, | ||
120 | int fh_len, int fh_type) | ||
121 | { | ||
122 | struct btrfs_fid *fid = (struct btrfs_fid *) fh; | ||
123 | u64 objectid, root_objectid; | ||
124 | u32 generation; | ||
125 | |||
126 | if ((fh_type != FILEID_BTRFS_WITH_PARENT || | ||
127 | fh_len != BTRFS_FID_SIZE_CONNECTABLE) && | ||
128 | (fh_type != FILEID_BTRFS_WITH_PARENT_ROOT || | ||
129 | fh_len != BTRFS_FID_SIZE_CONNECTABLE_ROOT) && | ||
130 | (fh_type != FILEID_BTRFS_WITHOUT_PARENT || | ||
131 | fh_len != BTRFS_FID_SIZE_NON_CONNECTABLE)) | ||
132 | return NULL; | ||
133 | |||
134 | objectid = fid->objectid; | ||
135 | root_objectid = fid->root_objectid; | ||
136 | generation = fid->gen; | ||
137 | |||
138 | return btrfs_get_dentry(sb, objectid, root_objectid, generation); | ||
139 | } | ||
140 | |||
141 | static struct dentry *btrfs_get_parent(struct dentry *child) | ||
142 | { | ||
143 | struct inode *dir = child->d_inode; | ||
144 | struct inode *inode; | ||
145 | struct dentry *parent; | ||
146 | struct btrfs_root *root = BTRFS_I(dir)->root; | ||
147 | struct btrfs_key key; | ||
148 | struct btrfs_path *path; | ||
149 | struct extent_buffer *leaf; | ||
150 | u32 nritems; | ||
151 | int slot; | ||
152 | u64 objectid; | ||
153 | int ret; | ||
154 | |||
155 | path = btrfs_alloc_path(); | ||
156 | |||
157 | key.objectid = dir->i_ino; | ||
158 | btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY); | ||
159 | key.offset = 0; | ||
160 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | ||
161 | BUG_ON(ret == 0); | ||
162 | ret = 0; | ||
163 | |||
164 | leaf = path->nodes[0]; | ||
165 | slot = path->slots[0]; | ||
166 | nritems = btrfs_header_nritems(leaf); | ||
167 | if (slot >= nritems) { | ||
168 | ret = btrfs_next_leaf(root, path); | ||
169 | if (ret) { | ||
170 | btrfs_free_path(path); | ||
171 | goto out; | ||
172 | } | ||
173 | leaf = path->nodes[0]; | ||
174 | slot = path->slots[0]; | ||
175 | } | ||
176 | |||
177 | btrfs_free_path(path); | ||
178 | |||
179 | btrfs_item_key_to_cpu(leaf, &key, slot); | ||
180 | if (key.objectid != dir->i_ino || key.type != BTRFS_INODE_REF_KEY) | ||
181 | goto out; | ||
182 | |||
183 | objectid = key.offset; | ||
184 | |||
185 | /* Build a new key for the inode item */ | ||
186 | key.objectid = objectid; | ||
187 | btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); | ||
188 | key.offset = 0; | ||
189 | |||
190 | inode = btrfs_iget(root->fs_info->sb, &key, root, NULL); | ||
191 | |||
192 | parent = d_obtain_alias(inode); | ||
193 | if (!parent) | ||
194 | parent = ERR_PTR(-ENOMEM); | ||
195 | |||
196 | return parent; | ||
197 | |||
198 | out: | ||
199 | btrfs_free_path(path); | ||
200 | return ERR_PTR(-EINVAL); | ||
201 | } | ||
202 | |||
203 | const struct export_operations btrfs_export_ops = { | ||
204 | .encode_fh = btrfs_encode_fh, | ||
205 | .fh_to_dentry = btrfs_fh_to_dentry, | ||
206 | .fh_to_parent = btrfs_fh_to_parent, | ||
207 | .get_parent = btrfs_get_parent, | ||
208 | }; | ||
diff --git a/fs/btrfs/export.h b/fs/btrfs/export.h new file mode 100644 index 000000000000..074348a95841 --- /dev/null +++ b/fs/btrfs/export.h | |||
@@ -0,0 +1,19 @@ | |||
1 | #ifndef BTRFS_EXPORT_H | ||
2 | #define BTRFS_EXPORT_H | ||
3 | |||
4 | #include <linux/exportfs.h> | ||
5 | |||
6 | extern const struct export_operations btrfs_export_ops; | ||
7 | |||
8 | struct btrfs_fid { | ||
9 | u64 objectid; | ||
10 | u64 root_objectid; | ||
11 | u32 gen; | ||
12 | |||
13 | u64 parent_objectid; | ||
14 | u32 parent_gen; | ||
15 | |||
16 | u64 parent_root_objectid; | ||
17 | } __attribute__ ((packed)); | ||
18 | |||
19 | #endif | ||
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index eb4b357d05e1..e830e0ed409a 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c | |||
@@ -46,6 +46,7 @@ | |||
46 | #include "xattr.h" | 46 | #include "xattr.h" |
47 | #include "volumes.h" | 47 | #include "volumes.h" |
48 | #include "version.h" | 48 | #include "version.h" |
49 | #include "export.h" | ||
49 | 50 | ||
50 | #define BTRFS_SUPER_MAGIC 0x9123683E | 51 | #define BTRFS_SUPER_MAGIC 0x9123683E |
51 | 52 | ||
@@ -303,6 +304,7 @@ static int btrfs_fill_super(struct super_block * sb, | |||
303 | sb->s_maxbytes = MAX_LFS_FILESIZE; | 304 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
304 | sb->s_magic = BTRFS_SUPER_MAGIC; | 305 | sb->s_magic = BTRFS_SUPER_MAGIC; |
305 | sb->s_op = &btrfs_super_ops; | 306 | sb->s_op = &btrfs_super_ops; |
307 | sb->s_export_op = &btrfs_export_ops; | ||
306 | sb->s_xattr = btrfs_xattr_handlers; | 308 | sb->s_xattr = btrfs_xattr_handlers; |
307 | sb->s_time_gran = 1; | 309 | sb->s_time_gran = 1; |
308 | sb->s_flags |= MS_POSIXACL; | 310 | sb->s_flags |= MS_POSIXACL; |