1/* 2 * linux/fs/hfsplus/wrapper.c 3 * 4 * Copyright (C) 2001 5 * Brad Boyer (flar@allandria.com) 6 * (C) 2003 Ardis Technologies <roman@ardistech.com> 7 * 8 * Handling of HFS wrappers around HFS+ volumes 9 */ 10 11#include <linux/fs.h> 12#include <linux/blkdev.h> 13#include <linux/cdrom.h> 14#include <linux/genhd.h> 15#include <asm/unaligned.h> 16 17#include "hfsplus_fs.h" 18#include "hfsplus_raw.h" 19 20struct hfsplus_wd { 21 u32 ablk_size; 22 u16 ablk_start; 23 u16 embed_start; 24 u16 embed_count; 25}; 26 27static void hfsplus_end_io_sync(struct bio *bio, int err) 28{ 29 if (err) 30 clear_bit(BIO_UPTODATE, &bio->bi_flags); 31 complete(bio->bi_private); 32} 33 34int hfsplus_submit_bio(struct block_device *bdev, sector_t sector, 35 void *data, int rw) 36{ 37 DECLARE_COMPLETION_ONSTACK(wait); 38 struct bio *bio; 39 int ret = 0; 40 41 bio = bio_alloc(GFP_NOIO, 1); 42 bio->bi_sector = sector; 43 bio->bi_bdev = bdev; 44 bio->bi_end_io = hfsplus_end_io_sync; 45 bio->bi_private = &wait; 46 47 /* 48 * We always submit one sector at a time, so bio_add_page must not fail. 49 */ 50 if (bio_add_page(bio, virt_to_page(data), HFSPLUS_SECTOR_SIZE, 51 offset_in_page(data)) != HFSPLUS_SECTOR_SIZE) 52 BUG(); 53 54 submit_bio(rw, bio); 55 wait_for_completion(&wait); 56 57 if (!bio_flagged(bio, BIO_UPTODATE)) 58 ret = -EIO; 59 60 bio_put(bio); 61 return ret; 62} 63 64static int hfsplus_read_mdb(void *bufptr, struct hfsplus_wd *wd) 65{ 66 u32 extent; 67 u16 attrib; 68 __be16 sig; 69 70 sig = *(__be16 *)(bufptr + HFSP_WRAPOFF_EMBEDSIG); 71 if (sig != cpu_to_be16(HFSPLUS_VOLHEAD_SIG) && 72 sig != cpu_to_be16(HFSPLUS_VOLHEAD_SIGX)) 73 return 0; 74 75 attrib = be16_to_cpu(*(__be16 *)(bufptr + HFSP_WRAPOFF_ATTRIB)); 76 if (!(attrib & HFSP_WRAP_ATTRIB_SLOCK) || 77 !(attrib & HFSP_WRAP_ATTRIB_SPARED)) 78 return 0; 79 80 wd->ablk_size = be32_to_cpu(*(__be32 *)(bufptr + HFSP_WRAPOFF_ABLKSIZE)); 81 if (wd->ablk_size < HFSPLUS_SECTOR_SIZE) 82 return 0; 83 if (wd->ablk_size % HFSPLUS_SECTOR_SIZE) 84 return 0; 85 wd->ablk_start = be16_to_cpu(*(__be16 *)(bufptr + HFSP_WRAPOFF_ABLKSTART)); 86 87 extent = get_unaligned_be32(bufptr + HFSP_WRAPOFF_EMBEDEXT); 88 wd->embed_start = (extent >> 16) & 0xFFFF; 89 wd->embed_count = extent & 0xFFFF; 90 91 return 1; 92} 93 94static int hfsplus_get_last_session(struct super_block *sb, 95 sector_t *start, sector_t *size) 96{ 97 struct cdrom_multisession ms_info; 98 struct cdrom_tocentry te; 99 int res; 100 101 /* default values */ 102 *start = 0; 103 *size = sb->s_bdev->bd_inode->i_size >> 9; 104 105 if (HFSPLUS_SB(sb).session >= 0) { 106 te.cdte_track = HFSPLUS_SB(sb).session; 107 te.cdte_format = CDROM_LBA; 108 res = ioctl_by_bdev(sb->s_bdev, CDROMREADTOCENTRY, (unsigned long)&te); 109 if (!res && (te.cdte_ctrl & CDROM_DATA_TRACK) == 4) { 110 *start = (sector_t)te.cdte_addr.lba << 2; 111 return 0; 112 } 113 printk(KERN_ERR "hfs: invalid session number or type of track\n"); 114 return -EINVAL; 115 } 116 ms_info.addr_format = CDROM_LBA; 117 res = ioctl_by_bdev(sb->s_bdev, CDROMMULTISESSION, (unsigned long)&ms_info); 118 if (!res && ms_info.xa_flag) 119 *start = (sector_t)ms_info.addr.lba << 2; 120 return 0; 121} 122 123/* Find the volume header and fill in some minimum bits in superblock */ 124/* Takes in super block, returns true if good data read */ 125int hfsplus_read_wrapper(struct super_block *sb) 126{ 127 struct buffer_head *bh; 128 struct hfsplus_vh *vhdr; 129 struct hfsplus_wd wd; 130 sector_t part_start, part_size; 131 u32 blocksize; 132 int error = 0; 133 134 error = -EINVAL; 135 blocksize = sb_min_blocksize(sb, HFSPLUS_SECTOR_SIZE); 136 if (!blocksize) 137 goto out; 138 139 if (hfsplus_get_last_session(sb, &part_start, &part_size)) 140 goto out; 141printk(KERN_EMERG"part_start=%x, part_size=%x",part_start,part_size); 142#if 0 143 if ((u64)part_start + part_size > 0x100000000ULL) { 144 pr_err("hfs: volumes larger than 2TB are not supported yet\n"); 145 goto out; 146 } 147#endif 148 HFSPLUS_SB(sb).s_vhdr=NULL; 149 150 error = -ENOMEM; 151/* 152 HFSPLUS_SB(sb).s_vhdr = kmalloc(HFSPLUS_SECTOR_SIZE, GFP_KERNEL); 153 if (!HFSPLUS_SB(sb).s_vhdr) 154 goto out; 155 HFSPLUS_SB(sb).s_backup_vhdr = kmalloc(HFSPLUS_SECTOR_SIZE, GFP_KERNEL); 156 if (!HFSPLUS_SB(sb).s_backup_vhdr) 157 goto out_free_vhdr; 158*/ 159/* Removed by Foxconn Antony 08/20/2013 end */ 160 161reread: 162 bh = sb_bread512(sb, part_start + HFSPLUS_VOLHEAD_SECTOR, vhdr); 163 if (!bh) 164 { 165 goto out_free_backup_vhdr; 166 } 167 168 error = -EINVAL; 169 switch (vhdr->signature) 170 { 171 case cpu_to_be16(HFSPLUS_VOLHEAD_SIGX): 172 set_bit(HFSPLUS_SB_HFSX, &HFSPLUS_SB(sb).flags); 173 /*FALLTHRU*/ 174 case cpu_to_be16(HFSPLUS_VOLHEAD_SIG): 175 break; 176 case cpu_to_be16(HFSP_WRAP_MAGIC): 177 if (!hfsplus_read_mdb(vhdr, &wd)) 178 goto out_free_backup_vhdr; 179 wd.ablk_size >>= HFSPLUS_SECTOR_SHIFT; 180 part_start += wd.ablk_start + wd.embed_start * wd.ablk_size; 181 part_size = wd.embed_count * wd.ablk_size; 182 brelse(bh); 183 goto reread; 184 default: 185 /* 186 * Check for a partition block. 187 * 188 * (should do this only for cdrom/loop though) 189 */ 190 brelse(bh); 191 if (hfs_part_find(sb, &part_start, &part_size)) 192 { 193 goto out_free_backup_vhdr; 194 } 195 goto reread; 196 } 197 198 199 blocksize = be32_to_cpu(vhdr->blocksize); 200 brelse(bh); 201 202 /* block size must be at least as large as a sector 203 * and a multiple of 2 204 */ 205 if (blocksize < HFSPLUS_SECTOR_SIZE || 206 ((blocksize - 1) & blocksize)) 207 goto out_free_backup_vhdr; 208 HFSPLUS_SB(sb).alloc_blksz = blocksize; 209 HFSPLUS_SB(sb).alloc_blksz_shift = 0; 210 while ((blocksize >>= 1) != 0) 211 HFSPLUS_SB(sb).alloc_blksz_shift++; 212 blocksize = min(HFSPLUS_SB(sb).alloc_blksz, (u32)PAGE_SIZE); 213 214 /* align block size to block offset */ 215 while (part_start & ((blocksize >> HFSPLUS_SECTOR_SHIFT) - 1)) 216 blocksize >>= 1; 217 218 if (sb_set_blocksize(sb, blocksize) != blocksize) { 219 printk(KERN_ERR "hfs: unable to set blocksize to %u!\n", blocksize); 220 goto out_free_backup_vhdr; 221 } 222 223 HFSPLUS_SB(sb).blockoffset = part_start >> 224 (sb->s_blocksize_bits - HFSPLUS_SECTOR_SHIFT); 225 HFSPLUS_SB(sb).part_start = part_start; 226 HFSPLUS_SB(sb).sect_count = part_size; 227 HFSPLUS_SB(sb).fs_shift = HFSPLUS_SB(sb).alloc_blksz_shift - 228 sb->s_blocksize_bits; 229 230 bh = sb_bread512(sb, part_start + HFSPLUS_VOLHEAD_SECTOR, vhdr); 231 if(!bh) 232 goto out_free_backup_vhdr; 233 234 HFSPLUS_SB(sb).s_vhbh = bh; 235 HFSPLUS_SB(sb).s_vhdr = vhdr; 236 return 0; 237 238out_free_backup_vhdr: 239// if(HFSPLUS_SB(sb).s_backup_vhdr) 240// kfree(HFSPLUS_SB(sb).s_backup_vhdr); 241out_free_vhdr: 242// if(HFSPLUS_SB(sb).s_vhdr) 243// kfree(HFSPLUS_SB(sb).s_vhdr); 244out: 245// brelse(bh); 246 return error; 247} 248