diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/hfs/mdb.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/hfs/mdb.c')
-rw-r--r-- | fs/hfs/mdb.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/fs/hfs/mdb.c b/fs/hfs/mdb.c new file mode 100644 index 000000000000..4efb640c4d0c --- /dev/null +++ b/fs/hfs/mdb.c | |||
@@ -0,0 +1,343 @@ | |||
1 | /* | ||
2 | * linux/fs/hfs/mdb.c | ||
3 | * | ||
4 | * Copyright (C) 1995-1997 Paul H. Hargrove | ||
5 | * (C) 2003 Ardis Technologies <roman@ardistech.com> | ||
6 | * This file may be distributed under the terms of the GNU General Public License. | ||
7 | * | ||
8 | * This file contains functions for reading/writing the MDB. | ||
9 | */ | ||
10 | |||
11 | #include <linux/cdrom.h> | ||
12 | #include <linux/genhd.h> | ||
13 | |||
14 | #include "hfs_fs.h" | ||
15 | #include "btree.h" | ||
16 | |||
17 | /*================ File-local data types ================*/ | ||
18 | |||
19 | /* | ||
20 | * The HFS Master Directory Block (MDB). | ||
21 | * | ||
22 | * Also known as the Volume Information Block (VIB), this structure is | ||
23 | * the HFS equivalent of a superblock. | ||
24 | * | ||
25 | * Reference: _Inside Macintosh: Files_ pages 2-59 through 2-62 | ||
26 | * | ||
27 | * modified for HFS Extended | ||
28 | */ | ||
29 | |||
30 | static int hfs_get_last_session(struct super_block *sb, | ||
31 | sector_t *start, sector_t *size) | ||
32 | { | ||
33 | struct cdrom_multisession ms_info; | ||
34 | struct cdrom_tocentry te; | ||
35 | int res; | ||
36 | |||
37 | /* default values */ | ||
38 | *start = 0; | ||
39 | *size = sb->s_bdev->bd_inode->i_size >> 9; | ||
40 | |||
41 | if (HFS_SB(sb)->session >= 0) { | ||
42 | te.cdte_track = HFS_SB(sb)->session; | ||
43 | te.cdte_format = CDROM_LBA; | ||
44 | res = ioctl_by_bdev(sb->s_bdev, CDROMREADTOCENTRY, (unsigned long)&te); | ||
45 | if (!res && (te.cdte_ctrl & CDROM_DATA_TRACK) == 4) { | ||
46 | *start = (sector_t)te.cdte_addr.lba << 2; | ||
47 | return 0; | ||
48 | } | ||
49 | printk(KERN_ERR "HFS: Invalid session number or type of track\n"); | ||
50 | return -EINVAL; | ||
51 | } | ||
52 | ms_info.addr_format = CDROM_LBA; | ||
53 | res = ioctl_by_bdev(sb->s_bdev, CDROMMULTISESSION, (unsigned long)&ms_info); | ||
54 | if (!res && ms_info.xa_flag) | ||
55 | *start = (sector_t)ms_info.addr.lba << 2; | ||
56 | return 0; | ||
57 | } | ||
58 | |||
59 | /* | ||
60 | * hfs_mdb_get() | ||
61 | * | ||
62 | * Build the in-core MDB for a filesystem, including | ||
63 | * the B-trees and the volume bitmap. | ||
64 | */ | ||
65 | int hfs_mdb_get(struct super_block *sb) | ||
66 | { | ||
67 | struct buffer_head *bh; | ||
68 | struct hfs_mdb *mdb, *mdb2; | ||
69 | unsigned int block; | ||
70 | char *ptr; | ||
71 | int off2, len, size, sect; | ||
72 | sector_t part_start, part_size; | ||
73 | loff_t off; | ||
74 | __be16 attrib; | ||
75 | |||
76 | /* set the device driver to 512-byte blocks */ | ||
77 | size = sb_min_blocksize(sb, HFS_SECTOR_SIZE); | ||
78 | if (!size) | ||
79 | return -EINVAL; | ||
80 | |||
81 | if (hfs_get_last_session(sb, &part_start, &part_size)) | ||
82 | return -EINVAL; | ||
83 | while (1) { | ||
84 | /* See if this is an HFS filesystem */ | ||
85 | bh = sb_bread512(sb, part_start + HFS_MDB_BLK, mdb); | ||
86 | if (!bh) | ||
87 | goto out; | ||
88 | |||
89 | if (mdb->drSigWord == cpu_to_be16(HFS_SUPER_MAGIC)) | ||
90 | break; | ||
91 | brelse(bh); | ||
92 | |||
93 | /* check for a partition block | ||
94 | * (should do this only for cdrom/loop though) | ||
95 | */ | ||
96 | if (hfs_part_find(sb, &part_start, &part_size)) | ||
97 | goto out; | ||
98 | } | ||
99 | |||
100 | HFS_SB(sb)->alloc_blksz = size = be32_to_cpu(mdb->drAlBlkSiz); | ||
101 | if (!size || (size & (HFS_SECTOR_SIZE - 1))) { | ||
102 | hfs_warn("hfs_fs: bad allocation block size %d\n", size); | ||
103 | goto out_bh; | ||
104 | } | ||
105 | |||
106 | size = min(HFS_SB(sb)->alloc_blksz, (u32)PAGE_SIZE); | ||
107 | /* size must be a multiple of 512 */ | ||
108 | while (size & (size - 1)) | ||
109 | size -= HFS_SECTOR_SIZE; | ||
110 | sect = be16_to_cpu(mdb->drAlBlSt) + part_start; | ||
111 | /* align block size to first sector */ | ||
112 | while (sect & ((size - 1) >> HFS_SECTOR_SIZE_BITS)) | ||
113 | size >>= 1; | ||
114 | /* align block size to weird alloc size */ | ||
115 | while (HFS_SB(sb)->alloc_blksz & (size - 1)) | ||
116 | size >>= 1; | ||
117 | brelse(bh); | ||
118 | if (!sb_set_blocksize(sb, size)) { | ||
119 | printk("hfs_fs: unable to set blocksize to %u\n", size); | ||
120 | goto out; | ||
121 | } | ||
122 | |||
123 | bh = sb_bread512(sb, part_start + HFS_MDB_BLK, mdb); | ||
124 | if (!bh) | ||
125 | goto out; | ||
126 | if (mdb->drSigWord != cpu_to_be16(HFS_SUPER_MAGIC)) | ||
127 | goto out_bh; | ||
128 | |||
129 | HFS_SB(sb)->mdb_bh = bh; | ||
130 | HFS_SB(sb)->mdb = mdb; | ||
131 | |||
132 | /* These parameters are read from the MDB, and never written */ | ||
133 | HFS_SB(sb)->part_start = part_start; | ||
134 | HFS_SB(sb)->fs_ablocks = be16_to_cpu(mdb->drNmAlBlks); | ||
135 | HFS_SB(sb)->fs_div = HFS_SB(sb)->alloc_blksz >> sb->s_blocksize_bits; | ||
136 | HFS_SB(sb)->clumpablks = be32_to_cpu(mdb->drClpSiz) / | ||
137 | HFS_SB(sb)->alloc_blksz; | ||
138 | if (!HFS_SB(sb)->clumpablks) | ||
139 | HFS_SB(sb)->clumpablks = 1; | ||
140 | HFS_SB(sb)->fs_start = (be16_to_cpu(mdb->drAlBlSt) + part_start) >> | ||
141 | (sb->s_blocksize_bits - HFS_SECTOR_SIZE_BITS); | ||
142 | |||
143 | /* These parameters are read from and written to the MDB */ | ||
144 | HFS_SB(sb)->free_ablocks = be16_to_cpu(mdb->drFreeBks); | ||
145 | HFS_SB(sb)->next_id = be32_to_cpu(mdb->drNxtCNID); | ||
146 | HFS_SB(sb)->root_files = be16_to_cpu(mdb->drNmFls); | ||
147 | HFS_SB(sb)->root_dirs = be16_to_cpu(mdb->drNmRtDirs); | ||
148 | HFS_SB(sb)->file_count = be32_to_cpu(mdb->drFilCnt); | ||
149 | HFS_SB(sb)->folder_count = be32_to_cpu(mdb->drDirCnt); | ||
150 | |||
151 | /* TRY to get the alternate (backup) MDB. */ | ||
152 | sect = part_start + part_size - 2; | ||
153 | bh = sb_bread512(sb, sect, mdb2); | ||
154 | if (bh) { | ||
155 | if (mdb2->drSigWord == cpu_to_be16(HFS_SUPER_MAGIC)) { | ||
156 | HFS_SB(sb)->alt_mdb_bh = bh; | ||
157 | HFS_SB(sb)->alt_mdb = mdb2; | ||
158 | } else | ||
159 | brelse(bh); | ||
160 | } | ||
161 | |||
162 | if (!HFS_SB(sb)->alt_mdb) { | ||
163 | hfs_warn("hfs_fs: unable to locate alternate MDB\n"); | ||
164 | hfs_warn("hfs_fs: continuing without an alternate MDB\n"); | ||
165 | } | ||
166 | |||
167 | HFS_SB(sb)->bitmap = (__be32 *)__get_free_pages(GFP_KERNEL, PAGE_SIZE < 8192 ? 1 : 0); | ||
168 | if (!HFS_SB(sb)->bitmap) | ||
169 | goto out; | ||
170 | |||
171 | /* read in the bitmap */ | ||
172 | block = be16_to_cpu(mdb->drVBMSt) + part_start; | ||
173 | off = (loff_t)block << HFS_SECTOR_SIZE_BITS; | ||
174 | size = (HFS_SB(sb)->fs_ablocks + 8) / 8; | ||
175 | ptr = (u8 *)HFS_SB(sb)->bitmap; | ||
176 | while (size) { | ||
177 | bh = sb_bread(sb, off >> sb->s_blocksize_bits); | ||
178 | if (!bh) { | ||
179 | hfs_warn("hfs_fs: unable to read volume bitmap\n"); | ||
180 | goto out; | ||
181 | } | ||
182 | off2 = off & (sb->s_blocksize - 1); | ||
183 | len = min((int)sb->s_blocksize - off2, size); | ||
184 | memcpy(ptr, bh->b_data + off2, len); | ||
185 | brelse(bh); | ||
186 | ptr += len; | ||
187 | off += len; | ||
188 | size -= len; | ||
189 | } | ||
190 | |||
191 | HFS_SB(sb)->ext_tree = hfs_btree_open(sb, HFS_EXT_CNID, hfs_ext_keycmp); | ||
192 | if (!HFS_SB(sb)->ext_tree) { | ||
193 | hfs_warn("hfs_fs: unable to open extent tree\n"); | ||
194 | goto out; | ||
195 | } | ||
196 | HFS_SB(sb)->cat_tree = hfs_btree_open(sb, HFS_CAT_CNID, hfs_cat_keycmp); | ||
197 | if (!HFS_SB(sb)->cat_tree) { | ||
198 | hfs_warn("hfs_fs: unable to open catalog tree\n"); | ||
199 | goto out; | ||
200 | } | ||
201 | |||
202 | attrib = mdb->drAtrb; | ||
203 | if (!(attrib & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) { | ||
204 | hfs_warn("HFS-fs warning: Filesystem was not cleanly unmounted, " | ||
205 | "running fsck.hfs is recommended. mounting read-only.\n"); | ||
206 | sb->s_flags |= MS_RDONLY; | ||
207 | } | ||
208 | if ((attrib & cpu_to_be16(HFS_SB_ATTRIB_SLOCK))) { | ||
209 | hfs_warn("HFS-fs: Filesystem is marked locked, mounting read-only.\n"); | ||
210 | sb->s_flags |= MS_RDONLY; | ||
211 | } | ||
212 | if (!(sb->s_flags & MS_RDONLY)) { | ||
213 | /* Mark the volume uncleanly unmounted in case we crash */ | ||
214 | attrib &= cpu_to_be16(~HFS_SB_ATTRIB_UNMNT); | ||
215 | attrib |= cpu_to_be16(HFS_SB_ATTRIB_INCNSTNT); | ||
216 | mdb->drAtrb = attrib; | ||
217 | mdb->drWrCnt = cpu_to_be32(be32_to_cpu(mdb->drWrCnt) + 1); | ||
218 | mdb->drLsMod = hfs_mtime(); | ||
219 | |||
220 | mark_buffer_dirty(HFS_SB(sb)->mdb_bh); | ||
221 | hfs_buffer_sync(HFS_SB(sb)->mdb_bh); | ||
222 | } | ||
223 | |||
224 | return 0; | ||
225 | |||
226 | out_bh: | ||
227 | brelse(bh); | ||
228 | out: | ||
229 | hfs_mdb_put(sb); | ||
230 | return -EIO; | ||
231 | } | ||
232 | |||
233 | /* | ||
234 | * hfs_mdb_commit() | ||
235 | * | ||
236 | * Description: | ||
237 | * This updates the MDB on disk (look also at hfs_write_super()). | ||
238 | * It does not check, if the superblock has been modified, or | ||
239 | * if the filesystem has been mounted read-only. It is mainly | ||
240 | * called by hfs_write_super() and hfs_btree_extend(). | ||
241 | * Input Variable(s): | ||
242 | * struct hfs_mdb *mdb: Pointer to the hfs MDB | ||
243 | * int backup; | ||
244 | * Output Variable(s): | ||
245 | * NONE | ||
246 | * Returns: | ||
247 | * void | ||
248 | * Preconditions: | ||
249 | * 'mdb' points to a "valid" (struct hfs_mdb). | ||
250 | * Postconditions: | ||
251 | * The HFS MDB and on disk will be updated, by copying the possibly | ||
252 | * modified fields from the in memory MDB (in native byte order) to | ||
253 | * the disk block buffer. | ||
254 | * If 'backup' is non-zero then the alternate MDB is also written | ||
255 | * and the function doesn't return until it is actually on disk. | ||
256 | */ | ||
257 | void hfs_mdb_commit(struct super_block *sb) | ||
258 | { | ||
259 | struct hfs_mdb *mdb = HFS_SB(sb)->mdb; | ||
260 | |||
261 | if (test_and_clear_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags)) { | ||
262 | /* These parameters may have been modified, so write them back */ | ||
263 | mdb->drLsMod = hfs_mtime(); | ||
264 | mdb->drFreeBks = cpu_to_be16(HFS_SB(sb)->free_ablocks); | ||
265 | mdb->drNxtCNID = cpu_to_be32(HFS_SB(sb)->next_id); | ||
266 | mdb->drNmFls = cpu_to_be16(HFS_SB(sb)->root_files); | ||
267 | mdb->drNmRtDirs = cpu_to_be16(HFS_SB(sb)->root_dirs); | ||
268 | mdb->drFilCnt = cpu_to_be32(HFS_SB(sb)->file_count); | ||
269 | mdb->drDirCnt = cpu_to_be32(HFS_SB(sb)->folder_count); | ||
270 | |||
271 | /* write MDB to disk */ | ||
272 | mark_buffer_dirty(HFS_SB(sb)->mdb_bh); | ||
273 | } | ||
274 | |||
275 | /* write the backup MDB, not returning until it is written. | ||
276 | * we only do this when either the catalog or extents overflow | ||
277 | * files grow. */ | ||
278 | if (test_and_clear_bit(HFS_FLG_ALT_MDB_DIRTY, &HFS_SB(sb)->flags) && | ||
279 | HFS_SB(sb)->alt_mdb) { | ||
280 | hfs_inode_write_fork(HFS_SB(sb)->ext_tree->inode, mdb->drXTExtRec, | ||
281 | &mdb->drXTFlSize, NULL); | ||
282 | hfs_inode_write_fork(HFS_SB(sb)->cat_tree->inode, mdb->drCTExtRec, | ||
283 | &mdb->drCTFlSize, NULL); | ||
284 | memcpy(HFS_SB(sb)->alt_mdb, HFS_SB(sb)->mdb, HFS_SECTOR_SIZE); | ||
285 | HFS_SB(sb)->alt_mdb->drAtrb |= cpu_to_be16(HFS_SB_ATTRIB_UNMNT); | ||
286 | HFS_SB(sb)->alt_mdb->drAtrb &= cpu_to_be16(~HFS_SB_ATTRIB_INCNSTNT); | ||
287 | mark_buffer_dirty(HFS_SB(sb)->alt_mdb_bh); | ||
288 | hfs_buffer_sync(HFS_SB(sb)->alt_mdb_bh); | ||
289 | } | ||
290 | |||
291 | if (test_and_clear_bit(HFS_FLG_BITMAP_DIRTY, &HFS_SB(sb)->flags)) { | ||
292 | struct buffer_head *bh; | ||
293 | sector_t block; | ||
294 | char *ptr; | ||
295 | int off, size, len; | ||
296 | |||
297 | block = be16_to_cpu(HFS_SB(sb)->mdb->drVBMSt) + HFS_SB(sb)->part_start; | ||
298 | off = (block << HFS_SECTOR_SIZE_BITS) & (sb->s_blocksize - 1); | ||
299 | block >>= sb->s_blocksize_bits - HFS_SECTOR_SIZE_BITS; | ||
300 | size = (HFS_SB(sb)->fs_ablocks + 7) / 8; | ||
301 | ptr = (u8 *)HFS_SB(sb)->bitmap; | ||
302 | while (size) { | ||
303 | bh = sb_bread(sb, block); | ||
304 | if (!bh) { | ||
305 | hfs_warn("hfs_fs: unable to read volume bitmap\n"); | ||
306 | break; | ||
307 | } | ||
308 | len = min((int)sb->s_blocksize - off, size); | ||
309 | memcpy(bh->b_data + off, ptr, len); | ||
310 | mark_buffer_dirty(bh); | ||
311 | brelse(bh); | ||
312 | block++; | ||
313 | off = 0; | ||
314 | ptr += len; | ||
315 | size -= len; | ||
316 | } | ||
317 | } | ||
318 | } | ||
319 | |||
320 | void hfs_mdb_close(struct super_block *sb) | ||
321 | { | ||
322 | /* update volume attributes */ | ||
323 | if (sb->s_flags & MS_RDONLY) | ||
324 | return; | ||
325 | HFS_SB(sb)->mdb->drAtrb |= cpu_to_be16(HFS_SB_ATTRIB_UNMNT); | ||
326 | HFS_SB(sb)->mdb->drAtrb &= cpu_to_be16(~HFS_SB_ATTRIB_INCNSTNT); | ||
327 | mark_buffer_dirty(HFS_SB(sb)->mdb_bh); | ||
328 | } | ||
329 | |||
330 | /* | ||
331 | * hfs_mdb_put() | ||
332 | * | ||
333 | * Release the resources associated with the in-core MDB. */ | ||
334 | void hfs_mdb_put(struct super_block *sb) | ||
335 | { | ||
336 | /* free the B-trees */ | ||
337 | hfs_btree_close(HFS_SB(sb)->ext_tree); | ||
338 | hfs_btree_close(HFS_SB(sb)->cat_tree); | ||
339 | |||
340 | /* free the buffers holding the primary and alternate MDBs */ | ||
341 | brelse(HFS_SB(sb)->mdb_bh); | ||
342 | brelse(HFS_SB(sb)->alt_mdb_bh); | ||
343 | } | ||