| /* |
| * linux/fs/hfsplus/extents.c |
| * |
| * Copyright (C) 2001 |
| * Brad Boyer (flar@allandria.com) |
| * (C) 2003 Ardis Technologies <roman@ardistech.com> |
| * |
| * Handling of Extents both in catalog and extents overflow trees |
| */ |
| |
| #include <linux/errno.h> |
| #include <linux/fs.h> |
| #include <linux/pagemap.h> |
| |
| #include "hfsplus_fs.h" |
| #include "hfsplus_raw.h" |
| |
| /* Compare two extents keys, returns 0 on same, pos/neg for difference */ |
| int hfsplus_ext_cmp_key(const hfsplus_btree_key *k1, |
| const hfsplus_btree_key *k2) |
| { |
| __be32 k1id, k2id; |
| __be32 k1s, k2s; |
| |
| k1id = k1->ext.cnid; |
| k2id = k2->ext.cnid; |
| if (k1id != k2id) |
| return be32_to_cpu(k1id) < be32_to_cpu(k2id) ? -1 : 1; |
| |
| if (k1->ext.fork_type != k2->ext.fork_type) |
| return k1->ext.fork_type < k2->ext.fork_type ? -1 : 1; |
| |
| k1s = k1->ext.start_block; |
| k2s = k2->ext.start_block; |
| if (k1s == k2s) |
| return 0; |
| return be32_to_cpu(k1s) < be32_to_cpu(k2s) ? -1 : 1; |
| } |
| |
| static void hfsplus_ext_build_key(hfsplus_btree_key *key, u32 cnid, |
| u32 block, u8 type) |
| { |
| key->key_len = cpu_to_be16(HFSPLUS_EXT_KEYLEN - 2); |
| key->ext.cnid = cpu_to_be32(cnid); |
| key->ext.start_block = cpu_to_be32(block); |
| key->ext.fork_type = type; |
| key->ext.pad = 0; |
| } |
| |
| static u32 hfsplus_ext_find_block(struct hfsplus_extent *ext, u32 off) |
| { |
| int i; |
| u32 count; |
| |
| for (i = 0; i < 8; ext++, i++) { |
| count = be32_to_cpu(ext->block_count); |
| if (off < count) |
| return be32_to_cpu(ext->start_block) + off; |
| off -= count; |
| } |
| /* panic? */ |
| return 0; |
| } |
| |
| static int hfsplus_ext_block_count(struct hfsplus_extent *ext) |
| { |
| int i; |
| u32 count = 0; |
| |
| for (i = 0; i < 8; ext++, i++) |
| count += be32_to_cpu(ext->block_count); |
| return count; |
| } |
| |
| static u32 hfsplus_ext_lastblock(struct hfsplus_extent *ext) |
| { |
| int i; |
| |
| ext += 7; |
| for (i = 0; i < 7; ext--, i++) |
| if (ext->block_count) |
| break; |
| return be32_to_cpu(ext->start_block) + be32_to_cpu(ext->block_count); |
| } |
| |
| static void __hfsplus_ext_write_extent(struct inode *inode, struct hfs_find_data *fd) |
| { |
| struct hfsplus_inode_info *hip = HFSPLUS_I(inode); |
| int res; |
| |
| WARN_ON(!mutex_is_locked(&hip->extents_lock)); |
| |
| hfsplus_ext_build_key(fd->search_key, inode->i_ino, hip->cached_start, |
| HFSPLUS_IS_RSRC(inode) ? |
| HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA); |
| |
| res = hfs_brec_find(fd); |
| if (hip->extent_state & HFSPLUS_EXT_NEW) { |
| if (res != -ENOENT) |
| return; |
| hfs_brec_insert(fd, hip->cached_extents, |
| sizeof(hfsplus_extent_rec)); |
| hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); |
| } else { |
| if (res) |
| return; |
| hfs_bnode_write(fd->bnode, hip->cached_extents, |
| fd->entryoffset, fd->entrylength); |
| hip->extent_state &= ~HFSPLUS_EXT_DIRTY; |
| } |
| } |
| |
| static void hfsplus_ext_write_extent_locked(struct inode *inode) |
| { |
| if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) { |
| struct hfs_find_data fd; |
| |
| hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd); |
| __hfsplus_ext_write_extent(inode, &fd); |
| hfs_find_exit(&fd); |
| } |
| } |
| |
| void hfsplus_ext_write_extent(struct inode *inode) |
| { |
| mutex_lock(&HFSPLUS_I(inode)->extents_lock); |
| hfsplus_ext_write_extent_locked(inode); |
| mutex_unlock(&HFSPLUS_I(inode)->extents_lock); |
| } |
| |
| static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd, |
| struct hfsplus_extent *extent, |
| u32 cnid, u32 block, u8 type) |
| { |
| int res; |
| |
| hfsplus_ext_build_key(fd->search_key, cnid, block, type); |
| fd->key->ext.cnid = 0; |
| res = hfs_brec_find(fd); |
| if (res && res != -ENOENT) |
| return res; |
| if (fd->key->ext.cnid != fd->search_key->ext.cnid || |
| fd->key->ext.fork_type != fd->search_key->ext.fork_type) |
| return -ENOENT; |
| if (fd->entrylength != sizeof(hfsplus_extent_rec)) |
| return -EIO; |
| hfs_bnode_read(fd->bnode, extent, fd->entryoffset, sizeof(hfsplus_extent_rec)); |
| return 0; |
| } |
| |
| static inline int __hfsplus_ext_cache_extent(struct hfs_find_data *fd, struct inode *inode, u32 block) |
| { |
| struct hfsplus_inode_info *hip = HFSPLUS_I(inode); |
| int res; |
| |
| WARN_ON(!mutex_is_locked(&hip->extents_lock)); |
| |
| if (hip->extent_state & HFSPLUS_EXT_DIRTY) |
| __hfsplus_ext_write_extent(inode, fd); |
| |
| res = __hfsplus_ext_read_extent(fd, hip->cached_extents, inode->i_ino, |
| block, HFSPLUS_IS_RSRC(inode) ? |
| HFSPLUS_TYPE_RSRC : |
| HFSPLUS_TYPE_DATA); |
| if (!res) { |
| hip->cached_start = be32_to_cpu(fd->key->ext.start_block); |
| hip->cached_blocks = hfsplus_ext_block_count(hip->cached_extents); |
| } else { |
| hip->cached_start = hip->cached_blocks = 0; |
| hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); |
| } |
| return res; |
| } |
| |
| static int hfsplus_ext_read_extent(struct inode *inode, u32 block) |
| { |
| struct hfsplus_inode_info *hip = HFSPLUS_I(inode); |
| struct hfs_find_data fd; |
| int res; |
| |
| if (block >= hip->cached_start && |
| block < hip->cached_start + hip->cached_blocks) |
| return 0; |
| |
| hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd); |
| res = __hfsplus_ext_cache_extent(&fd, inode, block); |
| hfs_find_exit(&fd); |
| return res; |
| } |
| |
| /* Get a block at iblock for inode, possibly allocating if create */ |
| int hfsplus_get_block(struct inode *inode, sector_t iblock, |
| struct buffer_head *bh_result, int create) |
| { |
| struct super_block *sb = inode->i_sb; |
| struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb); |
| struct hfsplus_inode_info *hip = HFSPLUS_I(inode); |
| int res = -EIO; |
| u32 ablock, dblock, mask; |
| int shift; |
| |
| /* Convert inode block to disk allocation block */ |
| shift = sbi->alloc_blksz_shift - sb->s_blocksize_bits; |
| ablock = iblock >> sbi->fs_shift; |
| |
| if (iblock >= hip->fs_blocks) { |
| if (iblock > hip->fs_blocks || !create) |
| return -EIO; |
| if (ablock >= hip->alloc_blocks) { |
| res = hfsplus_file_extend(inode); |
| if (res) |
| return res; |
| } |
| } else |
| create = 0; |
| |
| if (ablock < hip->first_blocks) { |
| dblock = hfsplus_ext_find_block(hip->first_extents, ablock); |
| goto done; |
| } |
| |
| if (inode->i_ino == HFSPLUS_EXT_CNID) |
| return -EIO; |
| |
| mutex_lock(&hip->extents_lock); |
| res = hfsplus_ext_read_extent(inode, ablock); |
| if (!res) { |
| dblock = hfsplus_ext_find_block(hip->cached_extents, |
| ablock - hip->cached_start); |
| } else { |
| mutex_unlock(&hip->extents_lock); |
| return -EIO; |
| } |
| mutex_unlock(&hip->extents_lock); |
| |
| done: |
| dprint(DBG_EXTENT, "get_block(%lu): %llu - %u\n", inode->i_ino, (long long)iblock, dblock); |
| mask = (1 << sbi->fs_shift) - 1; |
| map_bh(bh_result, sb, (dblock << sbi->fs_shift) + sbi->blockoffset + (iblock & mask)); |
| if (create) { |
| set_buffer_new(bh_result); |
| hip->phys_size += sb->s_blocksize; |
| hip->fs_blocks++; |
| inode_add_bytes(inode, sb->s_blocksize); |
| mark_inode_dirty(inode); |
| } |
| return 0; |
| } |
| |
| static void hfsplus_dump_extent(struct hfsplus_extent *extent) |
| { |
| int i; |
| |
| dprint(DBG_EXTENT, " "); |
| for (i = 0; i < 8; i++) |
| dprint(DBG_EXTENT, " %u:%u", be32_to_cpu(extent[i].start_block), |
| be32_to_cpu(extent[i].block_count)); |
| dprint(DBG_EXTENT, "\n"); |
| } |
| |
| static int hfsplus_add_extent(struct hfsplus_extent *extent, u32 offset, |
| u32 alloc_block, u32 block_count) |
| { |
| u32 count, start; |
| int i; |
| |
| hfsplus_dump_extent(extent); |
| for (i = 0; i < 8; extent++, i++) { |
| count = be32_to_cpu(extent->block_count); |
| if (offset == count) { |
| start = be32_to_cpu(extent->start_block); |
| if (alloc_block != start + count) { |
| if (++i >= 8) |
| return -ENOSPC; |
| extent++; |
| extent->start_block = cpu_to_be32(alloc_block); |
| } else |
| block_count += count; |
| extent->block_count = cpu_to_be32(block_count); |
| return 0; |
| } else if (offset < count) |
| break; |
| offset -= count; |
| } |
| /* panic? */ |
| return -EIO; |
| } |
| |
| static int hfsplus_free_extents(struct super_block *sb, |
| struct hfsplus_extent *extent, |
| u32 offset, u32 block_nr) |
| { |
| u32 count, start; |
| int i; |
| |
| hfsplus_dump_extent(extent); |
| for (i = 0; i < 8; extent++, i++) { |
| count = be32_to_cpu(extent->block_count); |
| if (offset == count) |
| goto found; |
| else if (offset < count) |
| break; |
| offset -= count; |
| } |
| /* panic? */ |
| return -EIO; |
| found: |
| for (;;) { |
| start = be32_to_cpu(extent->start_block); |
| if (count <= block_nr) { |
| hfsplus_block_free(sb, start, count); |
| extent->block_count = 0; |
| extent->start_block = 0; |
| block_nr -= count; |
| } else { |
| count -= block_nr; |
| hfsplus_block_free(sb, start + count, block_nr); |
| extent->block_count = cpu_to_be32(count); |
| block_nr = 0; |
| } |
| if (!block_nr || !i) |
| return 0; |
| i--; |
| extent--; |
| count = be32_to_cpu(extent->block_count); |
| } |
| } |
| |
| int hfsplus_free_fork(struct super_block *sb, u32 cnid, struct hfsplus_fork_raw *fork, int type) |
| { |
| struct hfs_find_data fd; |
| hfsplus_extent_rec ext_entry; |
| u32 total_blocks, blocks, start; |
| int res, i; |
| |
| total_blocks = be32_to_cpu(fork->total_blocks); |
| if (!total_blocks) |
| return 0; |
| |
| blocks = 0; |
| for (i = 0; i < 8; i++) |
| blocks += be32_to_cpu(fork->extents[i].block_count); |
| |
| res = hfsplus_free_extents(sb, fork->extents, blocks, blocks); |
| if (res) |
| return res; |
| if (total_blocks == blocks) |
| return 0; |
| |
| hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd); |
| do { |
| res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid, |
| total_blocks, type); |
| if (res) |
| break; |
| start = be32_to_cpu(fd.key->ext.start_block); |
| hfsplus_free_extents(sb, ext_entry, |
| total_blocks - start, |
| total_blocks); |
| hfs_brec_remove(&fd); |
| total_blocks = start; |
| } while (total_blocks > blocks); |
| hfs_find_exit(&fd); |
| |
| return res; |
| } |
| |
| int hfsplus_file_extend(struct inode *inode) |
| { |
| struct super_block *sb = inode->i_sb; |
| struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb); |
| struct hfsplus_inode_info *hip = HFSPLUS_I(inode); |
| u32 start, len, goal; |
| int res; |
| |
| if (sbi->alloc_file->i_size * 8 < |
| sbi->total_blocks - sbi->free_blocks + 8) { |
| // extend alloc file |
| printk(KERN_ERR "hfs: extend alloc file! (%Lu,%u,%u)\n", |
| sbi->alloc_file->i_size * 8, |
| sbi->total_blocks, sbi->free_blocks); |
| return -ENOSPC; |
| } |
| |
| mutex_lock(&hip->extents_lock); |
| if (hip->alloc_blocks == hip->first_blocks) |
| goal = hfsplus_ext_lastblock(hip->first_extents); |
| else { |
| res = hfsplus_ext_read_extent(inode, hip->alloc_blocks); |
| if (res) |
| goto out; |
| goal = hfsplus_ext_lastblock(hip->cached_extents); |
| } |
| |
| len = hip->clump_blocks; |
| start = hfsplus_block_allocate(sb, sbi->total_blocks, goal, &len); |
| if (start >= sbi->total_blocks) { |
| start = hfsplus_block_allocate(sb, goal, 0, &len); |
| if (start >= goal) { |
| res = -ENOSPC; |
| goto out; |
| } |
| } |
| |
| dprint(DBG_EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len); |
| |
| if (hip->alloc_blocks <= hip->first_blocks) { |
| if (!hip->first_blocks) { |
| dprint(DBG_EXTENT, "first extents\n"); |
| /* no extents yet */ |
| hip->first_extents[0].start_block = cpu_to_be32(start); |
| hip->first_extents[0].block_count = cpu_to_be32(len); |
| res = 0; |
| } else { |
| /* try to append to extents in inode */ |
| res = hfsplus_add_extent(hip->first_extents, |
| hip->alloc_blocks, |
| start, len); |
| if (res == -ENOSPC) |
| goto insert_extent; |
| } |
| if (!res) { |
| hfsplus_dump_extent(hip->first_extents); |
| hip->first_blocks += len; |
| } |
| } else { |
| res = hfsplus_add_extent(hip->cached_extents, |
| hip->alloc_blocks - hip->cached_start, |
| start, len); |
| if (!res) { |
| hfsplus_dump_extent(hip->cached_extents); |
| hip->extent_state |= HFSPLUS_EXT_DIRTY; |
| hip->cached_blocks += len; |
| } else if (res == -ENOSPC) |
| goto insert_extent; |
| } |
| out: |
| mutex_unlock(&hip->extents_lock); |
| if (!res) { |
| hip->alloc_blocks += len; |
| mark_inode_dirty(inode); |
| } |
| return res; |
| |
| insert_extent: |
| dprint(DBG_EXTENT, "insert new extent\n"); |
| hfsplus_ext_write_extent_locked(inode); |
| |
| memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec)); |
| hip->cached_extents[0].start_block = cpu_to_be32(start); |
| hip->cached_extents[0].block_count = cpu_to_be32(len); |
| hfsplus_dump_extent(hip->cached_extents); |
| hip->extent_state |= HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW; |
| hip->cached_start = hip->alloc_blocks; |
| hip->cached_blocks = len; |
| |
| res = 0; |
| goto out; |
| } |
| |
| void hfsplus_file_truncate(struct inode *inode) |
| { |
| struct super_block *sb = inode->i_sb; |
| struct hfsplus_inode_info *hip = HFSPLUS_I(inode); |
| struct hfs_find_data fd; |
| u32 alloc_cnt, blk_cnt, start; |
| int res; |
| |
| dprint(DBG_INODE, "truncate: %lu, %Lu -> %Lu\n", |
| inode->i_ino, (long long)hip->phys_size, inode->i_size); |
| |
| if (inode->i_size > hip->phys_size) { |
| struct address_space *mapping = inode->i_mapping; |
| struct page *page; |
| void *fsdata; |
| u32 size = inode->i_size; |
| int res; |
| |
| res = pagecache_write_begin(NULL, mapping, size, 0, |
| AOP_FLAG_UNINTERRUPTIBLE, |
| &page, &fsdata); |
| if (res) |
| return; |
| res = pagecache_write_end(NULL, mapping, size, 0, 0, page, fsdata); |
| if (res < 0) |
| return; |
| mark_inode_dirty(inode); |
| return; |
| } else if (inode->i_size == hip->phys_size) |
| return; |
| |
| blk_cnt = (inode->i_size + HFSPLUS_SB(sb)->alloc_blksz - 1) >> |
| HFSPLUS_SB(sb)->alloc_blksz_shift; |
| alloc_cnt = hip->alloc_blocks; |
| if (blk_cnt == alloc_cnt) |
| goto out; |
| |
| mutex_lock(&hip->extents_lock); |
| hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd); |
| while (1) { |
| if (alloc_cnt == hip->first_blocks) { |
| hfsplus_free_extents(sb, hip->first_extents, |
| alloc_cnt, alloc_cnt - blk_cnt); |
| hfsplus_dump_extent(hip->first_extents); |
| hip->first_blocks = blk_cnt; |
| break; |
| } |
| res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt); |
| if (res) |
| break; |
| start = hip->cached_start; |
| hfsplus_free_extents(sb, hip->cached_extents, |
| alloc_cnt - start, alloc_cnt - blk_cnt); |
| hfsplus_dump_extent(hip->cached_extents); |
| if (blk_cnt > start) { |
| hip->extent_state |= HFSPLUS_EXT_DIRTY; |
| break; |
| } |
| alloc_cnt = start; |
| hip->cached_start = hip->cached_blocks = 0; |
| hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); |
| hfs_brec_remove(&fd); |
| } |
| hfs_find_exit(&fd); |
| mutex_unlock(&hip->extents_lock); |
| |
| hip->alloc_blocks = blk_cnt; |
| out: |
| hip->phys_size = inode->i_size; |
| hip->fs_blocks = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits; |
| inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits); |
| mark_inode_dirty(inode); |
| } |