// SPDX-License-Identifier: GPL-2.0-only /* * partition.c * * PURPOSE * Partition handling routines for the OSTA-UDF(tm) filesystem. * * COPYRIGHT * (C) 1998-2001 Ben Fennema * * HISTORY * * 12/06/98 blf Created file. * */ #include "udfdecl.h" #include "udf_sb.h" #include "udf_i.h" #include <linux/fs.h> #include <linux/string.h> #include <linux/mutex.h> uint32_t udf_get_pblock(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset) { struct udf_sb_info *sbi = UDF_SB(sb); struct udf_part_map *map; if (partition >= sbi->s_partitions) { udf_debug("block=%u, partition=%u, offset=%u: invalid partition\n", block, partition, offset); return 0xFFFFFFFF; } map = &sbi->s_partmaps[partition]; if (map->s_partition_func) return map->s_partition_func(sb, block, partition, offset); else return map->s_partition_root + block + offset; } uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset) { struct buffer_head *bh = NULL; uint32_t newblock; uint32_t index; uint32_t loc; struct udf_sb_info *sbi = UDF_SB(sb); struct udf_part_map *map; struct udf_virtual_data *vdata; struct udf_inode_info *iinfo = UDF_I(sbi->s_vat_inode); int err; map = &sbi->s_partmaps[partition]; vdata = &map->s_type_specific.s_virtual; if (block > vdata->s_num_entries) { udf_debug("Trying to access block beyond end of VAT (%u max %u)\n", block, vdata->s_num_entries); return 0xFFFFFFFF; } if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { loc = le32_to_cpu(((__le32 *)(iinfo->i_data + vdata->s_start_offset))[block]); goto translate; } index = (sb->s_blocksize - vdata->s_start_offset) / sizeof(uint32_t); if (block >= index) { block -= index; newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t))); index = block % (sb->s_blocksize / sizeof(uint32_t)); } else { newblock = 0; index = vdata->s_start_offset / sizeof(uint32_t) + block; } bh = udf_bread(sbi->s_vat_inode, newblock, 0, &err); if (!bh) { udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%u,%u)\n", sb, block, partition); return 0xFFFFFFFF; } loc = le32_to_cpu(((__le32 *)bh->b_data)[index]); brelse(bh); translate: if (iinfo->i_location.partitionReferenceNum == partition) { udf_debug("recursive call to udf_get_pblock!\n"); return 0xFFFFFFFF; } return udf_get_pblock(sb, loc, iinfo->i_location.partitionReferenceNum, offset); } inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset) { return udf_get_pblock_virt15(sb, block, partition, offset); } uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset) { int i; struct sparingTable *st = NULL; struct udf_sb_info *sbi = UDF_SB(sb); struct udf_part_map *map; uint32_t packet; struct udf_sparing_data *sdata; map = &sbi->s_partmaps[partition]; sdata = &map->s_type_specific.s_sparing; packet = (block + offset) & ~(sdata->s_packet_len - 1); for (i = 0; i < 4; i++) { if (sdata->s_spar_map[i] != NULL) { st = (struct sparingTable *) sdata->s_spar_map[i]->b_data; break; } } if (st) { for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) { struct sparingEntry *entry = &st->mapEntry[i]; u32 origLoc = le32_to_cpu(entry->origLocation); if (origLoc >= 0xFFFFFFF0) break; else if (origLoc == packet) return le32_to_cpu(entry->mappedLocation) + ((block + offset) & (sdata->s_packet_len - 1)); else if (origLoc > packet) break; } } return map->s_partition_root + block + offset; } int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block) { struct udf_sparing_data *sdata; struct sparingTable *st = NULL; struct sparingEntry mapEntry; uint32_t packet; int i, j, k, l; struct udf_sb_info *sbi = UDF_SB(sb); u16 reallocationTableLen; struct buffer_head *bh; int ret = 0; mutex_lock(&sbi->s_alloc_mutex); for (i = 0; i < sbi->s_partitions; i++) { struct udf_part_map *map = &sbi->s_partmaps[i]; if (old_block > map->s_partition_root && old_block < map->s_partition_root + map->s_partition_len) { sdata = &map->s_type_specific.s_sparing; packet = (old_block - map->s_partition_root) & ~(sdata->s_packet_len - 1); for (j = 0; j < 4; j++) if (sdata->s_spar_map[j] != NULL) { st = (struct sparingTable *) sdata->s_spar_map[j]->b_data; break; } if (!st) { ret = 1; goto out; } reallocationTableLen = le16_to_cpu(st->reallocationTableLen); for (k = 0; k < reallocationTableLen; k++) { struct sparingEntry *entry = &st->mapEntry[k]; u32 origLoc = le32_to_cpu(entry->origLocation); if (origLoc == 0xFFFFFFFF) { for (; j < 4; j++) { int len; bh = sdata->s_spar_map[j]; if (!bh) continue; st = (struct sparingTable *) bh->b_data; entry->origLocation = cpu_to_le32(packet); len = sizeof(struct sparingTable) + reallocationTableLen * sizeof(struct sparingEntry); udf_update_tag((char *)st, len); mark_buffer_dirty(bh); } *new_block = le32_to_cpu( entry->mappedLocation) + ((old_block - map->s_partition_root) & (sdata->s_packet_len - 1)); ret = 0; goto out; } else if (origLoc == packet) { *new_block = le32_to_cpu( entry->mappedLocation) + ((old_block - map->s_partition_root) & (sdata->s_packet_len - 1)); ret = 0; goto out; } else if (origLoc > packet) break; } for (l = k; l < reallocationTableLen; l++) { struct sparingEntry *entry = &st->mapEntry[l]; u32 origLoc = le32_to_cpu(entry->origLocation); if (origLoc != 0xFFFFFFFF) continue; for (; j < 4; j++) { bh = sdata->s_spar_map[j]; if (!bh) continue; st = (struct sparingTable *)bh->b_data; mapEntry = st->mapEntry[l]; mapEntry.origLocation = cpu_to_le32(packet); memmove(&st->mapEntry[k + 1], &st->mapEntry[k], (l - k) * sizeof(struct sparingEntry)); st->mapEntry[k] = mapEntry; udf_update_tag((char *)st, sizeof(struct sparingTable) + reallocationTableLen * sizeof(struct sparingEntry)); mark_buffer_dirty(bh); } *new_block = le32_to_cpu( st->mapEntry[k].mappedLocation) + ((old_block - map->s_partition_root) & (sdata->s_packet_len - 1)); ret = 0; goto out; } ret = 1; goto out; } /* if old_block */ } if (i == sbi->s_partitions) { /* outside of partitions */ /* for now, fail =) */ ret = 1; } out: mutex_unlock(&sbi->s_alloc_mutex); return ret; } static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block, uint16_t partition, uint32_t offset) { struct super_block *sb = inode->i_sb; struct udf_part_map *map; struct kernel_lb_addr eloc; uint32_t elen; sector_t ext_offset; struct extent_position epos = {}; uint32_t phyblock; if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) != (EXT_RECORDED_ALLOCATED >> 30)) phyblock = 0xFFFFFFFF; else { map = &UDF_SB(sb)->s_partmaps[partition]; /* map to sparable/physical partition desc */ phyblock = udf_get_pblock(sb, eloc.logicalBlockNum, map->s_type_specific.s_metadata.s_phys_partition_ref, ext_offset + offset); } brelse(epos.bh); return phyblock; } uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block, uint16_t partition, uint32_t offset) { struct udf_sb_info *sbi = UDF_SB(sb); struct udf_part_map *map; struct udf_meta_data *mdata; uint32_t retblk; struct inode *inode; udf_debug("READING from METADATA\n"); map = &sbi->s_partmaps[partition]; mdata = &map->s_type_specific.s_metadata; inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe; if (!inode) return 0xFFFFFFFF; retblk = udf_try_read_meta(inode, block, partition, offset); if (retblk == 0xFFFFFFFF && mdata->s_metadata_fe) { udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n"); if (!(mdata->s_flags & MF_MIRROR_FE_LOADED)) { mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb, mdata->s_mirror_file_loc, mdata->s_phys_partition_ref); if (IS_ERR(mdata->s_mirror_fe)) mdata->s_mirror_fe = NULL; mdata->s_flags |= MF_MIRROR_FE_LOADED; } inode = mdata->s_mirror_fe; if (!inode) return 0xFFFFFFFF; retblk = udf_try_read_meta(inode, block, partition, offset); } return retblk; }
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