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/hfsplus/part_tbl.c |
Linux-2.6.12-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/hfsplus/part_tbl.c')
-rw-r--r-- | fs/hfsplus/part_tbl.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/fs/hfsplus/part_tbl.c b/fs/hfsplus/part_tbl.c new file mode 100644 index 00000000000..ae783066fc3 --- /dev/null +++ b/fs/hfsplus/part_tbl.c | |||
@@ -0,0 +1,133 @@ | |||
1 | /* | ||
2 | * linux/fs/hfs/part_tbl.c | ||
3 | * | ||
4 | * Copyright (C) 1996-1997 Paul H. Hargrove | ||
5 | * This file may be distributed under the terms of the GNU General Public License. | ||
6 | * | ||
7 | * Original code to handle the new style Mac partition table based on | ||
8 | * a patch contributed by Holger Schemel (aeglos@valinor.owl.de). | ||
9 | * | ||
10 | * In function preconditions the term "valid" applied to a pointer to | ||
11 | * a structure means that the pointer is non-NULL and the structure it | ||
12 | * points to has all fields initialized to consistent values. | ||
13 | * | ||
14 | */ | ||
15 | |||
16 | #include "hfsplus_fs.h" | ||
17 | |||
18 | /* offsets to various blocks */ | ||
19 | #define HFS_DD_BLK 0 /* Driver Descriptor block */ | ||
20 | #define HFS_PMAP_BLK 1 /* First block of partition map */ | ||
21 | #define HFS_MDB_BLK 2 /* Block (w/i partition) of MDB */ | ||
22 | |||
23 | /* magic numbers for various disk blocks */ | ||
24 | #define HFS_DRVR_DESC_MAGIC 0x4552 /* "ER": driver descriptor map */ | ||
25 | #define HFS_OLD_PMAP_MAGIC 0x5453 /* "TS": old-type partition map */ | ||
26 | #define HFS_NEW_PMAP_MAGIC 0x504D /* "PM": new-type partition map */ | ||
27 | #define HFS_SUPER_MAGIC 0x4244 /* "BD": HFS MDB (super block) */ | ||
28 | #define HFS_MFS_SUPER_MAGIC 0xD2D7 /* MFS MDB (super block) */ | ||
29 | |||
30 | /* | ||
31 | * The new style Mac partition map | ||
32 | * | ||
33 | * For each partition on the media there is a physical block (512-byte | ||
34 | * block) containing one of these structures. These blocks are | ||
35 | * contiguous starting at block 1. | ||
36 | */ | ||
37 | struct new_pmap { | ||
38 | __be16 pmSig; /* signature */ | ||
39 | __be16 reSigPad; /* padding */ | ||
40 | __be32 pmMapBlkCnt; /* partition blocks count */ | ||
41 | __be32 pmPyPartStart; /* physical block start of partition */ | ||
42 | __be32 pmPartBlkCnt; /* physical block count of partition */ | ||
43 | u8 pmPartName[32]; /* (null terminated?) string | ||
44 | giving the name of this | ||
45 | partition */ | ||
46 | u8 pmPartType[32]; /* (null terminated?) string | ||
47 | giving the type of this | ||
48 | partition */ | ||
49 | /* a bunch more stuff we don't need */ | ||
50 | } __packed; | ||
51 | |||
52 | /* | ||
53 | * The old style Mac partition map | ||
54 | * | ||
55 | * The partition map consists for a 2-byte signature followed by an | ||
56 | * array of these structures. The map is terminated with an all-zero | ||
57 | * one of these. | ||
58 | */ | ||
59 | struct old_pmap { | ||
60 | __be16 pdSig; /* Signature bytes */ | ||
61 | struct old_pmap_entry { | ||
62 | __be32 pdStart; | ||
63 | __be32 pdSize; | ||
64 | __be32 pdFSID; | ||
65 | } pdEntry[42]; | ||
66 | } __packed; | ||
67 | |||
68 | /* | ||
69 | * hfs_part_find() | ||
70 | * | ||
71 | * Parse the partition map looking for the | ||
72 | * start and length of the 'part'th HFS partition. | ||
73 | */ | ||
74 | int hfs_part_find(struct super_block *sb, | ||
75 | sector_t *part_start, sector_t *part_size) | ||
76 | { | ||
77 | struct buffer_head *bh; | ||
78 | __be16 *data; | ||
79 | int i, size, res; | ||
80 | |||
81 | res = -ENOENT; | ||
82 | bh = sb_bread512(sb, *part_start + HFS_PMAP_BLK, data); | ||
83 | if (!bh) | ||
84 | return -EIO; | ||
85 | |||
86 | switch (be16_to_cpu(*data)) { | ||
87 | case HFS_OLD_PMAP_MAGIC: | ||
88 | { | ||
89 | struct old_pmap *pm; | ||
90 | struct old_pmap_entry *p; | ||
91 | |||
92 | pm = (struct old_pmap *)bh->b_data; | ||
93 | p = pm->pdEntry; | ||
94 | size = 42; | ||
95 | for (i = 0; i < size; p++, i++) { | ||
96 | if (p->pdStart && p->pdSize && | ||
97 | p->pdFSID == cpu_to_be32(0x54465331)/*"TFS1"*/ && | ||
98 | (HFSPLUS_SB(sb).part < 0 || HFSPLUS_SB(sb).part == i)) { | ||
99 | *part_start += be32_to_cpu(p->pdStart); | ||
100 | *part_size = be32_to_cpu(p->pdSize); | ||
101 | res = 0; | ||
102 | } | ||
103 | } | ||
104 | break; | ||
105 | } | ||
106 | case HFS_NEW_PMAP_MAGIC: | ||
107 | { | ||
108 | struct new_pmap *pm; | ||
109 | |||
110 | pm = (struct new_pmap *)bh->b_data; | ||
111 | size = be32_to_cpu(pm->pmMapBlkCnt); | ||
112 | for (i = 0; i < size;) { | ||
113 | if (!memcmp(pm->pmPartType,"Apple_HFS", 9) && | ||
114 | (HFSPLUS_SB(sb).part < 0 || HFSPLUS_SB(sb).part == i)) { | ||
115 | *part_start += be32_to_cpu(pm->pmPyPartStart); | ||
116 | *part_size = be32_to_cpu(pm->pmPartBlkCnt); | ||
117 | res = 0; | ||
118 | break; | ||
119 | } | ||
120 | brelse(bh); | ||
121 | bh = sb_bread512(sb, *part_start + HFS_PMAP_BLK + ++i, pm); | ||
122 | if (!bh) | ||
123 | return -EIO; | ||
124 | if (pm->pmSig != cpu_to_be16(HFS_NEW_PMAP_MAGIC)) | ||
125 | break; | ||
126 | } | ||
127 | break; | ||
128 | } | ||
129 | } | ||
130 | brelse(bh); | ||
131 | |||
132 | return res; | ||
133 | } | ||