[PATCH] HFS+ support

From: Roman Zippel <zippel@linux-m68k.org>

This driver adds full read/write support for HFS+ and is based on the
readonly driver by Brad Broyer.

Thanks to Ethan Benson <erbenson@alaska.net> for a number of patches to
make the driver more compliant with the spec.

fs/Kconfig

@@ -951,6 +951,18 @@ config HFS_FS
  To compile this file system support as a module, choose M here: the
  module will be called hfs.
 
+config HFSPLUS_FS
+ tristate "Apple Extended HFS file system support"
+ select NLS
+ help
+ If you say Y here, you will be able to mount extended format
+ Macintosh-formatted hard drive partitions with full read-write access.
+
+ This file system is often called HFS+ and was introduced with
+ MacOS 8. It includes all Mac specific filesystem data such as
+ data forks and creator codes, but it also has several UNIX
+ style features such as file ownership and permissions.
+
 config BEFS_FS
  tristate "BeOS file systemv(BeFS) support (read only) (EXPERIMENTAL)"
  depends on EXPERIMENTAL

fs/Makefile

@@ -62,6 +62,7 @@ obj-$(CONFIG_VFAT_FS) += vfat/
 obj-$(CONFIG_BFS_FS) += bfs/
 obj-$(CONFIG_ISO9660_FS) += isofs/
 obj-$(CONFIG_DEVFS_FS) += devfs/
+obj-$(CONFIG_HFSPLUS_FS) += hfsplus/ # Before hfs to find wrapped HFS+
 obj-$(CONFIG_HFS_FS) += hfs/
 obj-$(CONFIG_VXFS_FS) += freevxfs/
 obj-$(CONFIG_NFS_FS) += nfs/

fs/hfsplus/Makefile

@@ -0,0 +1,9 @@
+#
+## Makefile for the linux hfsplus filesystem routines.
+#
+
+obj-$(CONFIG_HFSPLUS_FS) += hfsplus.o
+
+hfsplus-objs := super.o options.o inode.o ioctl.o extents.o catalog.o dir.o btree.o \
+ bnode.o brec.o bfind.o tables.o unicode.o wrapper.o bitmap.o part_tbl.o
+

fs/hfsplus/bfind.c

@@ -0,0 +1,209 @@
+/*
+ * linux/fs/hfsplus/bfind.c
+ *
+ * Copyright (C) 2001
+ * Brad Boyer (flar@allandria.com)
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ *
+ * Search routines for btrees
+ */
+
+#include <linux/slab.h>
+#include "hfsplus_fs.h"
+
+int hfs_find_init(struct hfs_btree *tree, struct hfs_find_data *fd)
+{
+ void *ptr;
+
+ fd->tree = tree;
+ fd->bnode = NULL;
+ ptr = kmalloc(tree->max_key_len * 2 + 4, GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+ fd->search_key = ptr;
+ fd->key = ptr + tree->max_key_len + 2;
+ dprint(DBG_BNODE_REFS, "find_init: %d (%p)\n", tree->cnid, __builtin_return_address(0));
+ down(&tree->tree_lock);
+ return 0;
+}
+
+void hfs_find_exit(struct hfs_find_data *fd)
+{
+ hfs_bnode_put(fd->bnode);
+ kfree(fd->search_key);
+ dprint(DBG_BNODE_REFS, "find_exit: %d (%p)\n", fd->tree->cnid, __builtin_return_address(0));
+ up(&fd->tree->tree_lock);
+ fd->tree = NULL;
+}
+
+/* Find the record in bnode that best matches key (not greater than...)*/
+int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd)
+{
+ int cmpval;
+ u16 off, len, keylen;
+ int rec;
+ int b, e;
+ int res;
+
+ b = 0;
+ e = bnode->num_recs - 1;
+ res = -ENOENT;
+ do {
+ rec = (e + b) / 2;
+ len = hfs_brec_lenoff(bnode, rec, &off);
+ keylen = hfs_brec_keylen(bnode, rec);
+ hfs_bnode_read(bnode, fd->key, off, keylen);
+ cmpval = bnode->tree->keycmp(fd->key, fd->search_key);
+ if (!cmpval) {
+ e = rec;
+ res = 0;
+ goto done;
+ }
+ if (cmpval < 0)
+ b = rec + 1;
+ else
+ e = rec - 1;
+ } while (b <= e);
+ //printk("%d: %d,%d,%d\n", bnode->this, b, e, rec);
+ if (rec != e && e >= 0) {
+ len = hfs_brec_lenoff(bnode, e, &off);
+ keylen = hfs_brec_keylen(bnode, e);
+ hfs_bnode_read(bnode, fd->key, off, keylen);
+ }
+done:
+ fd->record = e;
+ fd->keyoffset = off;
+ fd->keylength = keylen;
+ fd->entryoffset = off + keylen;
+ fd->entrylength = len - keylen;
+ return res;
+}
+
+/* Traverse a B*Tree from the root to a leaf finding best fit to key */
+/* Return allocated copy of node found, set recnum to best record */
+int hfs_brec_find(struct hfs_find_data *fd)
+{
+ struct hfs_btree *tree;
+ struct hfs_bnode *bnode;
+ u32 data, nidx, parent;
+ int height, res;
+
+ tree = fd->tree;
+ if (fd->bnode)
+ hfs_bnode_put(fd->bnode);
+ fd->bnode = NULL;
+ nidx = tree->root;
+ if (!nidx)
+ return -ENOENT;
+ height = tree->depth;
+ res = 0;
+ parent = 0;
+ for (;;) {
+ bnode = hfs_bnode_find(tree, nidx);
+ if (IS_ERR(bnode)) {
+ res = PTR_ERR(bnode);
+ bnode = NULL;
+ break;
+ }
+ if (bnode->height != height)
+ goto invalid;
+ if (bnode->type != (--height ? HFS_NODE_INDEX : HFS_NODE_LEAF))
+ goto invalid;
+ bnode->parent = parent;
+
+ res = __hfs_brec_find(bnode, fd);
+ if (!height)
+ break;
+ if (fd->record < 0)
+ goto release;
+
+ parent = nidx;
+ hfs_bnode_read(bnode, &data, fd->entryoffset, 4);
+ nidx = be32_to_cpu(data);
+ hfs_bnode_put(bnode);
+ }
+ fd->bnode = bnode;
+ return res;
+
+invalid:
+ printk("HFS+-fs: inconsistency in B*Tree (%d,%d,%d,%u,%u)\n",
+ height, bnode->height, bnode->type, nidx, parent);
+ res = -EIO;
+release:
+ hfs_bnode_put(bnode);
+ return res;
+}
+
+int hfs_brec_read(struct hfs_find_data *fd, void *rec, int rec_len)
+{
+ int res;
+
+ res = hfs_brec_find(fd);
+ if (res)
+ return res;
+ if (fd->entrylength > rec_len)
+ return -EINVAL;
+ hfs_bnode_read(fd->bnode, rec, fd->entryoffset, fd->entrylength);
+ return 0;
+}
+
+int hfs_brec_goto(struct hfs_find_data *fd, int cnt)
+{
+ struct hfs_btree *tree;
+ struct hfs_bnode *bnode;
+ int idx, res = 0;
+ u16 off, len, keylen;
+
+ bnode = fd->bnode;
+ tree = bnode->tree;
+
+ if (cnt < 0) {
+ cnt = -cnt;
+ while (cnt > fd->record) {
+ cnt -= fd->record + 1;
+ fd->record = bnode->num_recs - 1;
+ idx = bnode->prev;
+ if (!idx) {
+ res = -ENOENT;
+ goto out;
+ }
+ hfs_bnode_put(bnode);
+ bnode = hfs_bnode_find(tree, idx);
+ if (IS_ERR(bnode)) {
+ res = PTR_ERR(bnode);
+ bnode = NULL;
+ goto out;
+ }
+ }
+ fd->record -= cnt;
+ } else {
+ while (cnt >= bnode->num_recs - fd->record) {
+ cnt -= bnode->num_recs - fd->record;
+ fd->record = 0;
+ idx = bnode->next;
+ if (!idx) {
+ res = -ENOENT;
+ goto out;
+ }
+ hfs_bnode_put(bnode);
+ bnode = hfs_bnode_find(tree, idx);
+ if (IS_ERR(bnode)) {
+ res = PTR_ERR(bnode);
+ bnode = NULL;
+ goto out;
+ }
+ }
+ fd->record += cnt;
+ }
+
+ len = hfs_brec_lenoff(bnode, fd->record, &off);
+ keylen = hfs_brec_keylen(bnode, fd->record);
+ fd->keyoffset = off;
+ fd->keylength = keylen;
+ fd->entryoffset = off + keylen;
+ fd->entrylength = len - keylen;
+ hfs_bnode_read(bnode, fd->key, off, keylen);
+out:
+ fd->bnode = bnode;
+ return res;
+}