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-rw-r--r--fs/hfsplus/extents.c505
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);
+}
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