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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/hfsplus/extents.c | |
download | kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/hfsplus/extents.c')
-rw-r--r-- | fs/hfsplus/extents.c | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/fs/hfsplus/extents.c b/fs/hfsplus/extents.c new file mode 100644 index 0000000..376498c --- /dev/null +++ b/fs/hfsplus/extents.c @@ -0,0 +1,505 @@ +/* + * 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 <linux/version.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(hfsplus_btree_key *k1, 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) +{ + int res; + + hfsplus_ext_build_key(fd->search_key, inode->i_ino, HFSPLUS_I(inode).cached_start, + HFSPLUS_IS_RSRC(inode) ? HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA); + res = hfs_brec_find(fd); + if (HFSPLUS_I(inode).flags & HFSPLUS_FLG_EXT_NEW) { + if (res != -ENOENT) + return; + hfs_brec_insert(fd, HFSPLUS_I(inode).cached_extents, sizeof(hfsplus_extent_rec)); + HFSPLUS_I(inode).flags &= ~(HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW); + } else { + if (res) + return; + hfs_bnode_write(fd->bnode, HFSPLUS_I(inode).cached_extents, fd->entryoffset, fd->entrylength); + HFSPLUS_I(inode).flags &= ~HFSPLUS_FLG_EXT_DIRTY; + } +} + +void hfsplus_ext_write_extent(struct inode *inode) +{ + if (HFSPLUS_I(inode).flags & HFSPLUS_FLG_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); + } +} + +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) +{ + int res; + + if (HFSPLUS_I(inode).flags & HFSPLUS_FLG_EXT_DIRTY) + __hfsplus_ext_write_extent(inode, fd); + + res = __hfsplus_ext_read_extent(fd, HFSPLUS_I(inode).cached_extents, inode->i_ino, + block, HFSPLUS_IS_RSRC(inode) ? HFSPLUS_TYPE_RSRC : HFSPLUS_TYPE_DATA); + if (!res) { + HFSPLUS_I(inode).cached_start = be32_to_cpu(fd->key->ext.start_block); + HFSPLUS_I(inode).cached_blocks = hfsplus_ext_block_count(HFSPLUS_I(inode).cached_extents); + } else { + HFSPLUS_I(inode).cached_start = HFSPLUS_I(inode).cached_blocks = 0; + HFSPLUS_I(inode).flags &= ~(HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW); + } + return res; +} + +static int hfsplus_ext_read_extent(struct inode *inode, u32 block) +{ + struct hfs_find_data fd; + int res; + + if (block >= HFSPLUS_I(inode).cached_start && + block < HFSPLUS_I(inode).cached_start + HFSPLUS_I(inode).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; + int res = -EIO; + u32 ablock, dblock, mask; + int shift; + + sb = inode->i_sb; + + /* Convert inode block to disk allocation block */ + shift = HFSPLUS_SB(sb).alloc_blksz_shift - sb->s_blocksize_bits; + ablock = iblock >> HFSPLUS_SB(sb).fs_shift; + + if (iblock >= HFSPLUS_I(inode).fs_blocks) { + if (iblock > HFSPLUS_I(inode).fs_blocks || !create) + return -EIO; + if (ablock >= HFSPLUS_I(inode).alloc_blocks) { + res = hfsplus_file_extend(inode); + if (res) + return res; + } + } else + create = 0; + + if (ablock < HFSPLUS_I(inode).first_blocks) { + dblock = hfsplus_ext_find_block(HFSPLUS_I(inode).first_extents, ablock); + goto done; + } + + down(&HFSPLUS_I(inode).extents_lock); + res = hfsplus_ext_read_extent(inode, ablock); + if (!res) { + dblock = hfsplus_ext_find_block(HFSPLUS_I(inode).cached_extents, ablock - + HFSPLUS_I(inode).cached_start); + } else { + up(&HFSPLUS_I(inode).extents_lock); + return -EIO; + } + up(&HFSPLUS_I(inode).extents_lock); + +done: + dprint(DBG_EXTENT, "get_block(%lu): %llu - %u\n", inode->i_ino, (long long)iblock, dblock); + mask = (1 << HFSPLUS_SB(sb).fs_shift) - 1; + map_bh(bh_result, sb, (dblock << HFSPLUS_SB(sb).fs_shift) + HFSPLUS_SB(sb).blockoffset + (iblock & mask)); + if (create) { + set_buffer_new(bh_result); + HFSPLUS_I(inode).phys_size += sb->s_blocksize; + HFSPLUS_I(inode).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; + u32 start, len, goal; + int res; + + if (HFSPLUS_SB(sb).alloc_file->i_size * 8 < HFSPLUS_SB(sb).total_blocks - HFSPLUS_SB(sb).free_blocks + 8) { + // extend alloc file + printk("extend alloc file! (%Lu,%u,%u)\n", HFSPLUS_SB(sb).alloc_file->i_size * 8, + HFSPLUS_SB(sb).total_blocks, HFSPLUS_SB(sb).free_blocks); + return -ENOSPC; + //BUG(); + } + + down(&HFSPLUS_I(inode).extents_lock); + if (HFSPLUS_I(inode).alloc_blocks == HFSPLUS_I(inode).first_blocks) + goal = hfsplus_ext_lastblock(HFSPLUS_I(inode).first_extents); + else { + res = hfsplus_ext_read_extent(inode, HFSPLUS_I(inode).alloc_blocks); + if (res) + goto out; + goal = hfsplus_ext_lastblock(HFSPLUS_I(inode).cached_extents); + } + + len = HFSPLUS_I(inode).clump_blocks; + start = hfsplus_block_allocate(sb, HFSPLUS_SB(sb).total_blocks, goal, &len); + if (start >= HFSPLUS_SB(sb).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 (HFSPLUS_I(inode).alloc_blocks <= HFSPLUS_I(inode).first_blocks) { + if (!HFSPLUS_I(inode).first_blocks) { + dprint(DBG_EXTENT, "first extents\n"); + /* no extents yet */ + HFSPLUS_I(inode).first_extents[0].start_block = cpu_to_be32(start); + HFSPLUS_I(inode).first_extents[0].block_count = cpu_to_be32(len); + res = 0; + } else { + /* try to append to extents in inode */ + res = hfsplus_add_extent(HFSPLUS_I(inode).first_extents, + HFSPLUS_I(inode).alloc_blocks, + start, len); + if (res == -ENOSPC) + goto insert_extent; + } + if (!res) { + hfsplus_dump_extent(HFSPLUS_I(inode).first_extents); + HFSPLUS_I(inode).first_blocks += len; + } + } else { + res = hfsplus_add_extent(HFSPLUS_I(inode).cached_extents, + HFSPLUS_I(inode).alloc_blocks - + HFSPLUS_I(inode).cached_start, + start, len); + if (!res) { + hfsplus_dump_extent(HFSPLUS_I(inode).cached_extents); + HFSPLUS_I(inode).flags |= HFSPLUS_FLG_EXT_DIRTY; + HFSPLUS_I(inode).cached_blocks += len; + } else if (res == -ENOSPC) + goto insert_extent; + } +out: + up(&HFSPLUS_I(inode).extents_lock); + if (!res) { + HFSPLUS_I(inode).alloc_blocks += len; + mark_inode_dirty(inode); + } + return res; + +insert_extent: + dprint(DBG_EXTENT, "insert new extent\n"); + hfsplus_ext_write_extent(inode); + + memset(HFSPLUS_I(inode).cached_extents, 0, sizeof(hfsplus_extent_rec)); + HFSPLUS_I(inode).cached_extents[0].start_block = cpu_to_be32(start); + HFSPLUS_I(inode).cached_extents[0].block_count = cpu_to_be32(len); + hfsplus_dump_extent(HFSPLUS_I(inode).cached_extents); + HFSPLUS_I(inode).flags |= HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW; + HFSPLUS_I(inode).cached_start = HFSPLUS_I(inode).alloc_blocks; + HFSPLUS_I(inode).cached_blocks = len; + + res = 0; + goto out; +} + +void hfsplus_file_truncate(struct inode *inode) +{ + struct super_block *sb = inode->i_sb; + 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)HFSPLUS_I(inode).phys_size, inode->i_size); + if (inode->i_size > HFSPLUS_I(inode).phys_size) { + struct address_space *mapping = inode->i_mapping; + struct page *page; + u32 size = inode->i_size - 1; + int res; + + page = grab_cache_page(mapping, size >> PAGE_CACHE_SHIFT); + if (!page) + return; + size &= PAGE_CACHE_SIZE - 1; + size++; + res = mapping->a_ops->prepare_write(NULL, page, size, size); + if (!res) + res = mapping->a_ops->commit_write(NULL, page, size, size); + if (res) + inode->i_size = HFSPLUS_I(inode).phys_size; + unlock_page(page); + page_cache_release(page); + mark_inode_dirty(inode); + return; + } + blk_cnt = (inode->i_size + HFSPLUS_SB(sb).alloc_blksz - 1) >> HFSPLUS_SB(sb).alloc_blksz_shift; + alloc_cnt = HFSPLUS_I(inode).alloc_blocks; + if (blk_cnt == alloc_cnt) + goto out; + + down(&HFSPLUS_I(inode).extents_lock); + hfs_find_init(HFSPLUS_SB(sb).ext_tree, &fd); + while (1) { + if (alloc_cnt == HFSPLUS_I(inode).first_blocks) { + hfsplus_free_extents(sb, HFSPLUS_I(inode).first_extents, + alloc_cnt, alloc_cnt - blk_cnt); + hfsplus_dump_extent(HFSPLUS_I(inode).first_extents); + HFSPLUS_I(inode).first_blocks = blk_cnt; + break; + } + res = __hfsplus_ext_cache_extent(&fd, inode, alloc_cnt); + if (res) + break; + start = HFSPLUS_I(inode).cached_start; + hfsplus_free_extents(sb, HFSPLUS_I(inode).cached_extents, + alloc_cnt - start, alloc_cnt - blk_cnt); + hfsplus_dump_extent(HFSPLUS_I(inode).cached_extents); + if (blk_cnt > start) { + HFSPLUS_I(inode).flags |= HFSPLUS_FLG_EXT_DIRTY; + break; + } + alloc_cnt = start; + HFSPLUS_I(inode).cached_start = HFSPLUS_I(inode).cached_blocks = 0; + HFSPLUS_I(inode).flags &= ~(HFSPLUS_FLG_EXT_DIRTY | HFSPLUS_FLG_EXT_NEW); + hfs_brec_remove(&fd); + } + hfs_find_exit(&fd); + up(&HFSPLUS_I(inode).extents_lock); + + HFSPLUS_I(inode).alloc_blocks = blk_cnt; +out: + HFSPLUS_I(inode).phys_size = inode->i_size; + HFSPLUS_I(inode).fs_blocks = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits; + inode_set_bytes(inode, HFSPLUS_I(inode).fs_blocks << sb->s_blocksize_bits); + mark_inode_dirty(inode); +} |