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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/hfs/part_tbl.c
downloadlinux-2.6.34-ux500-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
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/part_tbl.c')
-rw-r--r--fs/hfs/part_tbl.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/fs/hfs/part_tbl.c b/fs/hfs/part_tbl.c
new file mode 100644
index 00000000000..36add537d15
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+++ b/fs/hfs/part_tbl.c
@@ -0,0 +1,117 @@
+/*
+ * linux/fs/hfs/part_tbl.c
+ *
+ * Copyright (C) 1996-1997 Paul H. Hargrove
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ * This file may be distributed under the terms of the GNU General Public License.
+ *
+ * Original code to handle the new style Mac partition table based on
+ * a patch contributed by Holger Schemel (aeglos@valinor.owl.de).
+ */
+
+#include "hfs_fs.h"
+
+/*
+ * The new style Mac partition map
+ *
+ * For each partition on the media there is a physical block (512-byte
+ * block) containing one of these structures. These blocks are
+ * contiguous starting at block 1.
+ */
+struct new_pmap {
+ __be16 pmSig; /* signature */
+ __be16 reSigPad; /* padding */
+ __be32 pmMapBlkCnt; /* partition blocks count */
+ __be32 pmPyPartStart; /* physical block start of partition */
+ __be32 pmPartBlkCnt; /* physical block count of partition */
+ u8 pmPartName[32]; /* (null terminated?) string
+ giving the name of this
+ partition */
+ u8 pmPartType[32]; /* (null terminated?) string
+ giving the type of this
+ partition */
+ /* a bunch more stuff we don't need */
+} __packed;
+
+/*
+ * The old style Mac partition map
+ *
+ * The partition map consists for a 2-byte signature followed by an
+ * array of these structures. The map is terminated with an all-zero
+ * one of these.
+ */
+struct old_pmap {
+ __be16 pdSig; /* Signature bytes */
+ struct old_pmap_entry {
+ __be32 pdStart;
+ __be32 pdSize;
+ __be32 pdFSID;
+ } pdEntry[42];
+} __packed;
+
+/*
+ * hfs_part_find()
+ *
+ * Parse the partition map looking for the
+ * start and length of the 'part'th HFS partition.
+ */
+int hfs_part_find(struct super_block *sb,
+ sector_t *part_start, sector_t *part_size)
+{
+ struct buffer_head *bh;
+ __be16 *data;
+ int i, size, res;
+
+ res = -ENOENT;
+ bh = sb_bread512(sb, *part_start + HFS_PMAP_BLK, data);
+ if (!bh)
+ return -EIO;
+
+ switch (be16_to_cpu(*data)) {
+ case HFS_OLD_PMAP_MAGIC:
+ {
+ struct old_pmap *pm;
+ struct old_pmap_entry *p;
+
+ pm = (struct old_pmap *)bh->b_data;
+ p = pm->pdEntry;
+ size = 42;
+ for (i = 0; i < size; p++, i++) {
+ if (p->pdStart && p->pdSize &&
+ p->pdFSID == cpu_to_be32(0x54465331)/*"TFS1"*/ &&
+ (HFS_SB(sb)->part < 0 || HFS_SB(sb)->part == i)) {
+ *part_start += be32_to_cpu(p->pdStart);
+ *part_size = be32_to_cpu(p->pdSize);
+ res = 0;
+ }
+ }
+ break;
+ }
+ case HFS_NEW_PMAP_MAGIC:
+ {
+ struct new_pmap *pm;
+
+ pm = (struct new_pmap *)bh->b_data;
+ size = be32_to_cpu(pm->pmMapBlkCnt);
+ for (i = 0; i < size;) {
+ if (!memcmp(pm->pmPartType,"Apple_HFS", 9) &&
+ (HFS_SB(sb)->part < 0 || HFS_SB(sb)->part == i)) {
+ *part_start += be32_to_cpu(pm->pmPyPartStart);
+ *part_size = be32_to_cpu(pm->pmPartBlkCnt);
+ res = 0;
+ break;
+ }
+ brelse(bh);
+ bh = sb_bread512(sb, *part_start + HFS_PMAP_BLK + ++i, pm);
+ if (!bh)
+ return -EIO;
+ if (pm->pmSig != cpu_to_be16(HFS_NEW_PMAP_MAGIC))
+ break;
+ }
+ break;
+ }
+ }
+ brelse(bh);
+
+ return res;
+}