From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- fs/hfsplus/extents.c | 611 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 611 insertions(+) create mode 100644 fs/hfsplus/extents.c (limited to 'fs/hfsplus/extents.c') diff --git a/fs/hfsplus/extents.c b/fs/hfsplus/extents.c new file mode 100644 index 000000000..feca524ce --- /dev/null +++ b/fs/hfsplus/extents.c @@ -0,0 +1,611 @@ +/* + * linux/fs/hfsplus/extents.c + * + * Copyright (C) 2001 + * Brad Boyer (flar@allandria.com) + * (C) 2003 Ardis Technologies + * + * Handling of Extents both in catalog and extents overflow trees + */ + +#include +#include +#include + +#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 int __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, hfs_find_rec_by_key); + if (hip->extent_state & HFSPLUS_EXT_NEW) { + if (res != -ENOENT) + return res; + hfs_brec_insert(fd, hip->cached_extents, + sizeof(hfsplus_extent_rec)); + hip->extent_state &= ~(HFSPLUS_EXT_DIRTY | HFSPLUS_EXT_NEW); + } else { + if (res) + return res; + hfs_bnode_write(fd->bnode, hip->cached_extents, + fd->entryoffset, fd->entrylength); + hip->extent_state &= ~HFSPLUS_EXT_DIRTY; + } + + /* + * We can't just use hfsplus_mark_inode_dirty here, because we + * also get called from hfsplus_write_inode, which should not + * redirty the inode. Instead the callers have to be careful + * to explicily mark the inode dirty, too. + */ + set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags); + + return 0; +} + +static int hfsplus_ext_write_extent_locked(struct inode *inode) +{ + int res = 0; + + if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) { + struct hfs_find_data fd; + + res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd); + if (res) + return res; + res = __hfsplus_ext_write_extent(inode, &fd); + hfs_find_exit(&fd); + } + return res; +} + +int hfsplus_ext_write_extent(struct inode *inode) +{ + int res; + + mutex_lock(&HFSPLUS_I(inode)->extents_lock); + res = hfsplus_ext_write_extent_locked(inode); + mutex_unlock(&HFSPLUS_I(inode)->extents_lock); + + return res; +} + +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, hfs_find_rec_by_key); + 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) { + res = __hfsplus_ext_write_extent(inode, fd); + if (res) + return res; + } + + 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; + + res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd); + if (!res) { + 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; + sector_t sector; + int was_dirty = 0; + + /* Convert inode block to disk allocation block */ + 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, false); + 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); + + /* + * hfsplus_ext_read_extent will write out a cached extent into + * the extents btree. In that case we may have to mark the inode + * dirty even for a pure read of an extent here. + */ + was_dirty = (hip->extent_state & HFSPLUS_EXT_DIRTY); + res = hfsplus_ext_read_extent(inode, ablock); + if (res) { + mutex_unlock(&hip->extents_lock); + return -EIO; + } + dblock = hfsplus_ext_find_block(hip->cached_extents, + ablock - hip->cached_start); + mutex_unlock(&hip->extents_lock); + +done: + hfs_dbg(EXTENT, "get_block(%lu): %llu - %u\n", + inode->i_ino, (long long)iblock, dblock); + + mask = (1 << sbi->fs_shift) - 1; + sector = ((sector_t)dblock << sbi->fs_shift) + + sbi->blockoffset + (iblock & mask); + map_bh(bh_result, sb, sector); + + if (create) { + set_buffer_new(bh_result); + hip->phys_size += sb->s_blocksize; + hip->fs_blocks++; + inode_add_bytes(inode, sb->s_blocksize); + } + if (create || was_dirty) + mark_inode_dirty(inode); + return 0; +} + +static void hfsplus_dump_extent(struct hfsplus_extent *extent) +{ + int i; + + hfs_dbg(EXTENT, " "); + for (i = 0; i < 8; i++) + hfs_dbg_cont(EXTENT, " %u:%u", + be32_to_cpu(extent[i].start_block), + be32_to_cpu(extent[i].block_count)); + hfs_dbg_cont(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; + int err = 0; + + 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) { + err = hfsplus_block_free(sb, start, count); + if (err) { + pr_err("can't free extent\n"); + hfs_dbg(EXTENT, " start: %u count: %u\n", + start, count); + } + extent->block_count = 0; + extent->start_block = 0; + block_nr -= count; + } else { + count -= block_nr; + err = hfsplus_block_free(sb, start + count, block_nr); + if (err) { + pr_err("can't free extent\n"); + hfs_dbg(EXTENT, " start: %u count: %u\n", + start, count); + } + extent->block_count = cpu_to_be32(count); + block_nr = 0; + } + if (!block_nr || !i) { + /* + * Try to free all extents and + * return only last error + */ + return err; + } + 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; + + res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd); + if (res) + return res; + 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, bool zeroout) +{ + 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 */ + pr_err("extend alloc file! (%llu,%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; + } + } + + if (zeroout) { + res = sb_issue_zeroout(sb, start, len, GFP_NOFS); + if (res) + goto out; + } + + hfs_dbg(EXTENT, "extend %lu: %u,%u\n", inode->i_ino, start, len); + + if (hip->alloc_blocks <= hip->first_blocks) { + if (!hip->first_blocks) { + hfs_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: + if (!res) { + hip->alloc_blocks += len; + mutex_unlock(&hip->extents_lock); + hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY); + return 0; + } + mutex_unlock(&hip->extents_lock); + return res; + +insert_extent: + hfs_dbg(EXTENT, "insert new extent\n"); + res = hfsplus_ext_write_extent_locked(inode); + if (res) + goto out; + + 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; + + hfs_dbg(INODE, "truncate: %lu, %llu -> %llu\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; + loff_t size = inode->i_size; + + 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; + + mutex_lock(&hip->extents_lock); + + alloc_cnt = hip->alloc_blocks; + if (blk_cnt == alloc_cnt) + goto out_unlock; + + res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd); + if (res) { + mutex_unlock(&hip->extents_lock); + /* XXX: We lack error handling of hfsplus_file_truncate() */ + return; + } + 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); + + hip->alloc_blocks = blk_cnt; +out_unlock: + mutex_unlock(&hip->extents_lock); + 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); + hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ALLOC_DIRTY); +} -- cgit v1.2.3-54-g00ecf