123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158 |
- #include <linux/slab.h>
- #include "hfsplus_fs.h"
- #define HFS_DD_BLK 0
- #define HFS_PMAP_BLK 1
- #define HFS_MDB_BLK 2
- #define HFS_DRVR_DESC_MAGIC 0x4552
- #define HFS_OLD_PMAP_MAGIC 0x5453
- #define HFS_NEW_PMAP_MAGIC 0x504D
- #define HFS_SUPER_MAGIC 0x4244
- #define HFS_MFS_SUPER_MAGIC 0xD2D7
- struct new_pmap {
- __be16 pmSig;
- __be16 reSigPad;
- __be32 pmMapBlkCnt;
- __be32 pmPyPartStart;
- __be32 pmPartBlkCnt;
- u8 pmPartName[32];
- u8 pmPartType[32];
-
- } __packed;
- struct old_pmap {
- __be16 pdSig;
- struct old_pmap_entry {
- __be32 pdStart;
- __be32 pdSize;
- __be32 pdFSID;
- } pdEntry[42];
- } __packed;
- static int hfs_parse_old_pmap(struct super_block *sb, struct old_pmap *pm,
- sector_t *part_start, sector_t *part_size)
- {
- struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
- int i;
- for (i = 0; i < 42; i++) {
- struct old_pmap_entry *p = &pm->pdEntry[i];
- if (p->pdStart && p->pdSize &&
- p->pdFSID == cpu_to_be32(0x54465331) &&
- (sbi->part < 0 || sbi->part == i)) {
- *part_start += be32_to_cpu(p->pdStart);
- *part_size = be32_to_cpu(p->pdSize);
- return 0;
- }
- }
- return -ENOENT;
- }
- static int hfs_parse_new_pmap(struct super_block *sb, void *buf,
- struct new_pmap *pm, sector_t *part_start, sector_t *part_size)
- {
- struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
- int size = be32_to_cpu(pm->pmMapBlkCnt);
- int buf_size = hfsplus_min_io_size(sb);
- int res;
- int i = 0;
- do {
- if (!memcmp(pm->pmPartType, "Apple_HFS", 9) &&
- (sbi->part < 0 || sbi->part == i)) {
- *part_start += be32_to_cpu(pm->pmPyPartStart);
- *part_size = be32_to_cpu(pm->pmPartBlkCnt);
- return 0;
- }
- if (++i >= size)
- return -ENOENT;
- pm = (struct new_pmap *)((u8 *)pm + HFSPLUS_SECTOR_SIZE);
- if ((u8 *)pm - (u8 *)buf >= buf_size) {
- res = hfsplus_submit_bio(sb,
- *part_start + HFS_PMAP_BLK + i,
- buf, (void **)&pm, REQ_OP_READ,
- 0);
- if (res)
- return res;
- }
- } while (pm->pmSig == cpu_to_be16(HFS_NEW_PMAP_MAGIC));
- return -ENOENT;
- }
- int hfs_part_find(struct super_block *sb,
- sector_t *part_start, sector_t *part_size)
- {
- void *buf, *data;
- int res;
- buf = kmalloc(hfsplus_min_io_size(sb), GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- res = hfsplus_submit_bio(sb, *part_start + HFS_PMAP_BLK,
- buf, &data, REQ_OP_READ, 0);
- if (res)
- goto out;
- switch (be16_to_cpu(*((__be16 *)data))) {
- case HFS_OLD_PMAP_MAGIC:
- res = hfs_parse_old_pmap(sb, data, part_start, part_size);
- break;
- case HFS_NEW_PMAP_MAGIC:
- res = hfs_parse_new_pmap(sb, buf, data, part_start, part_size);
- break;
- default:
- res = -ENOENT;
- break;
- }
- out:
- kfree(buf);
- return res;
- }
|