Fixed MTP to work with TWRP

fs/hfs/super.c

@@ -0,0 +1,508 @@
+/*
+ *  linux/fs/hfs/super.c
+ *
+ * Copyright (C) 1995-1997  Paul H. Hargrove
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ * This file may be distributed under the terms of the GNU General Public License.
+ *
+ * This file contains hfs_read_super(), some of the super_ops and
+ * init_hfs_fs() and exit_hfs_fs().  The remaining super_ops are in
+ * inode.c since they deal with inodes.
+ *
+ * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
+ */
+
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/mount.h>
+#include <linux/init.h>
+#include <linux/nls.h>
+#include <linux/parser.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/vfs.h>
+
+#include "hfs_fs.h"
+#include "btree.h"
+
+static struct kmem_cache *hfs_inode_cachep;
+
+MODULE_LICENSE("GPL");
+
+static int hfs_sync_fs(struct super_block *sb, int wait)
+{
+	hfs_mdb_commit(sb);
+	return 0;
+}
+
+/*
+ * hfs_put_super()
+ *
+ * This is the put_super() entry in the super_operations structure for
+ * HFS filesystems.  The purpose is to release the resources
+ * associated with the superblock sb.
+ */
+static void hfs_put_super(struct super_block *sb)
+{
+	cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work);
+	hfs_mdb_close(sb);
+	/* release the MDB's resources */
+	hfs_mdb_put(sb);
+}
+
+static void flush_mdb(struct work_struct *work)
+{
+	struct hfs_sb_info *sbi;
+	struct super_block *sb;
+
+	sbi = container_of(work, struct hfs_sb_info, mdb_work.work);
+	sb = sbi->sb;
+
+	spin_lock(&sbi->work_lock);
+	sbi->work_queued = 0;
+	spin_unlock(&sbi->work_lock);
+
+	hfs_mdb_commit(sb);
+}
+
+void hfs_mark_mdb_dirty(struct super_block *sb)
+{
+	struct hfs_sb_info *sbi = HFS_SB(sb);
+	unsigned long delay;
+
+	if (sb->s_flags & MS_RDONLY)
+		return;
+
+	spin_lock(&sbi->work_lock);
+	if (!sbi->work_queued) {
+		delay = msecs_to_jiffies(dirty_writeback_interval * 10);
+		queue_delayed_work(system_long_wq, &sbi->mdb_work, delay);
+		sbi->work_queued = 1;
+	}
+	spin_unlock(&sbi->work_lock);
+}
+
+/*
+ * hfs_statfs()
+ *
+ * This is the statfs() entry in the super_operations structure for
+ * HFS filesystems.  The purpose is to return various data about the
+ * filesystem.
+ *
+ * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks.
+ */
+static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *sb = dentry->d_sb;
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+
+	buf->f_type = HFS_SUPER_MAGIC;
+	buf->f_bsize = sb->s_blocksize;
+	buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div;
+	buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div;
+	buf->f_bavail = buf->f_bfree;
+	buf->f_files = HFS_SB(sb)->fs_ablocks;
+	buf->f_ffree = HFS_SB(sb)->free_ablocks;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
+	buf->f_namelen = HFS_NAMELEN;
+
+	return 0;
+}
+
+static int hfs_remount(struct super_block *sb, int *flags, char *data)
+{
+	sync_filesystem(sb);
+	*flags |= MS_NODIRATIME;
+	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
+		return 0;
+	if (!(*flags & MS_RDONLY)) {
+		if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) {
+			pr_warn("filesystem was not cleanly unmounted, running fsck.hfs is recommended.  leaving read-only.\n");
+			sb->s_flags |= MS_RDONLY;
+			*flags |= MS_RDONLY;
+		} else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) {
+			pr_warn("filesystem is marked locked, leaving read-only.\n");
+			sb->s_flags |= MS_RDONLY;
+			*flags |= MS_RDONLY;
+		}
+	}
+	return 0;
+}
+
+static int hfs_show_options(struct seq_file *seq, struct dentry *root)
+{
+	struct hfs_sb_info *sbi = HFS_SB(root->d_sb);
+
+	if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f))
+		seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator);
+	if (sbi->s_type != cpu_to_be32(0x3f3f3f3f))
+		seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type);
+	seq_printf(seq, ",uid=%u,gid=%u",
+			from_kuid_munged(&init_user_ns, sbi->s_uid),
+			from_kgid_munged(&init_user_ns, sbi->s_gid));
+	if (sbi->s_file_umask != 0133)
+		seq_printf(seq, ",file_umask=%o", sbi->s_file_umask);
+	if (sbi->s_dir_umask != 0022)
+		seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask);
+	if (sbi->part >= 0)
+		seq_printf(seq, ",part=%u", sbi->part);
+	if (sbi->session >= 0)
+		seq_printf(seq, ",session=%u", sbi->session);
+	if (sbi->nls_disk)
+		seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset);
+	if (sbi->nls_io)
+		seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset);
+	if (sbi->s_quiet)
+		seq_printf(seq, ",quiet");
+	return 0;
+}
+
+static struct inode *hfs_alloc_inode(struct super_block *sb)
+{
+	struct hfs_inode_info *i;
+
+	i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL);
+	return i ? &i->vfs_inode : NULL;
+}
+
+static void hfs_i_callback(struct rcu_head *head)
+{
+	struct inode *inode = container_of(head, struct inode, i_rcu);
+	kmem_cache_free(hfs_inode_cachep, HFS_I(inode));
+}
+
+static void hfs_destroy_inode(struct inode *inode)
+{
+	call_rcu(&inode->i_rcu, hfs_i_callback);
+}
+
+static const struct super_operations hfs_super_operations = {
+	.alloc_inode	= hfs_alloc_inode,
+	.destroy_inode	= hfs_destroy_inode,
+	.write_inode	= hfs_write_inode,
+	.evict_inode	= hfs_evict_inode,
+	.put_super	= hfs_put_super,
+	.sync_fs	= hfs_sync_fs,
+	.statfs		= hfs_statfs,
+	.remount_fs     = hfs_remount,
+	.show_options	= hfs_show_options,
+};
+
+enum {
+	opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask,
+	opt_part, opt_session, opt_type, opt_creator, opt_quiet,
+	opt_codepage, opt_iocharset,
+	opt_err
+};
+
+static const match_table_t tokens = {
+	{ opt_uid, "uid=%u" },
+	{ opt_gid, "gid=%u" },
+	{ opt_umask, "umask=%o" },
+	{ opt_file_umask, "file_umask=%o" },
+	{ opt_dir_umask, "dir_umask=%o" },
+	{ opt_part, "part=%u" },
+	{ opt_session, "session=%u" },
+	{ opt_type, "type=%s" },
+	{ opt_creator, "creator=%s" },
+	{ opt_quiet, "quiet" },
+	{ opt_codepage, "codepage=%s" },
+	{ opt_iocharset, "iocharset=%s" },
+	{ opt_err, NULL }
+};
+
+static inline int match_fourchar(substring_t *arg, u32 *result)
+{
+	if (arg->to - arg->from != 4)
+		return -EINVAL;
+	memcpy(result, arg->from, 4);
+	return 0;
+}
+
+/*
+ * parse_options()
+ *
+ * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger
+ * This function is called by hfs_read_super() to parse the mount options.
+ */
+static int parse_options(char *options, struct hfs_sb_info *hsb)
+{
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+	int tmp, token;
+
+	/* initialize the sb with defaults */
+	hsb->s_uid = current_uid();
+	hsb->s_gid = current_gid();
+	hsb->s_file_umask = 0133;
+	hsb->s_dir_umask = 0022;
+	hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f);	/* == '????' */
+	hsb->s_quiet = 0;
+	hsb->part = -1;
+	hsb->session = -1;
+
+	if (!options)
+		return 1;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		if (!*p)
+			continue;
+
+		token = match_token(p, tokens, args);
+		switch (token) {
+		case opt_uid:
+			if (match_int(&args[0], &tmp)) {
+				pr_err("uid requires an argument\n");
+				return 0;
+			}
+			hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp);
+			if (!uid_valid(hsb->s_uid)) {
+				pr_err("invalid uid %d\n", tmp);
+				return 0;
+			}
+			break;
+		case opt_gid:
+			if (match_int(&args[0], &tmp)) {
+				pr_err("gid requires an argument\n");
+				return 0;
+			}
+			hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp);
+			if (!gid_valid(hsb->s_gid)) {
+				pr_err("invalid gid %d\n", tmp);
+				return 0;
+			}
+			break;
+		case opt_umask:
+			if (match_octal(&args[0], &tmp)) {
+				pr_err("umask requires a value\n");
+				return 0;
+			}
+			hsb->s_file_umask = (umode_t)tmp;
+			hsb->s_dir_umask = (umode_t)tmp;
+			break;
+		case opt_file_umask:
+			if (match_octal(&args[0], &tmp)) {
+				pr_err("file_umask requires a value\n");
+				return 0;
+			}
+			hsb->s_file_umask = (umode_t)tmp;
+			break;
+		case opt_dir_umask:
+			if (match_octal(&args[0], &tmp)) {
+				pr_err("dir_umask requires a value\n");
+				return 0;
+			}
+			hsb->s_dir_umask = (umode_t)tmp;
+			break;
+		case opt_part:
+			if (match_int(&args[0], &hsb->part)) {
+				pr_err("part requires an argument\n");
+				return 0;
+			}
+			break;
+		case opt_session:
+			if (match_int(&args[0], &hsb->session)) {
+				pr_err("session requires an argument\n");
+				return 0;
+			}
+			break;
+		case opt_type:
+			if (match_fourchar(&args[0], &hsb->s_type)) {
+				pr_err("type requires a 4 character value\n");
+				return 0;
+			}
+			break;
+		case opt_creator:
+			if (match_fourchar(&args[0], &hsb->s_creator)) {
+				pr_err("creator requires a 4 character value\n");
+				return 0;
+			}
+			break;
+		case opt_quiet:
+			hsb->s_quiet = 1;
+			break;
+		case opt_codepage:
+			if (hsb->nls_disk) {
+				pr_err("unable to change codepage\n");
+				return 0;
+			}
+			p = match_strdup(&args[0]);
+			if (p)
+				hsb->nls_disk = load_nls(p);
+			if (!hsb->nls_disk) {
+				pr_err("unable to load codepage \"%s\"\n", p);
+				kfree(p);
+				return 0;
+			}
+			kfree(p);
+			break;
+		case opt_iocharset:
+			if (hsb->nls_io) {
+				pr_err("unable to change iocharset\n");
+				return 0;
+			}
+			p = match_strdup(&args[0]);
+			if (p)
+				hsb->nls_io = load_nls(p);
+			if (!hsb->nls_io) {
+				pr_err("unable to load iocharset \"%s\"\n", p);
+				kfree(p);
+				return 0;
+			}
+			kfree(p);
+			break;
+		default:
+			return 0;
+		}
+	}
+
+	if (hsb->nls_disk && !hsb->nls_io) {
+		hsb->nls_io = load_nls_default();
+		if (!hsb->nls_io) {
+			pr_err("unable to load default iocharset\n");
+			return 0;
+		}
+	}
+	hsb->s_dir_umask &= 0777;
+	hsb->s_file_umask &= 0577;
+
+	return 1;
+}
+
+/*
+ * hfs_read_super()
+ *
+ * This is the function that is responsible for mounting an HFS
+ * filesystem.	It performs all the tasks necessary to get enough data
+ * from the disk to read the root inode.  This includes parsing the
+ * mount options, dealing with Macintosh partitions, reading the
+ * superblock and the allocation bitmap blocks, calling
+ * hfs_btree_init() to get the necessary data about the extents and
+ * catalog B-trees and, finally, reading the root inode into memory.
+ */
+static int hfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct hfs_sb_info *sbi;
+	struct hfs_find_data fd;
+	hfs_cat_rec rec;
+	struct inode *root_inode;
+	int res;
+
+	sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL);
+	if (!sbi)
+		return -ENOMEM;
+
+	sbi->sb = sb;
+	sb->s_fs_info = sbi;
+	spin_lock_init(&sbi->work_lock);
+	INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb);
+
+	res = -EINVAL;
+	if (!parse_options((char *)data, sbi)) {
+		pr_err("unable to parse mount options\n");
+		goto bail;
+	}
+
+	sb->s_op = &hfs_super_operations;
+	sb->s_flags |= MS_NODIRATIME;
+	mutex_init(&sbi->bitmap_lock);
+
+	res = hfs_mdb_get(sb);
+	if (res) {
+		if (!silent)
+			pr_warn("can't find a HFS filesystem on dev %s\n",
+				hfs_mdb_name(sb));
+		res = -EINVAL;
+		goto bail;
+	}
+
+	/* try to get the root inode */
+	res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
+	if (res)
+		goto bail_no_root;
+	res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd);
+	if (!res) {
+		if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) {
+			res =  -EIO;
+			goto bail;
+		}
+		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength);
+	}
+	if (res) {
+		hfs_find_exit(&fd);
+		goto bail_no_root;
+	}
+	res = -EINVAL;
+	root_inode = hfs_iget(sb, &fd.search_key->cat, &rec);
+	hfs_find_exit(&fd);
+	if (!root_inode)
+		goto bail_no_root;
+
+	sb->s_d_op = &hfs_dentry_operations;
+	res = -ENOMEM;
+	sb->s_root = d_make_root(root_inode);
+	if (!sb->s_root)
+		goto bail_no_root;
+
+	/* everything's okay */
+	return 0;
+
+bail_no_root:
+	pr_err("get root inode failed\n");
+bail:
+	hfs_mdb_put(sb);
+	return res;
+}
+
+static struct dentry *hfs_mount(struct file_system_type *fs_type,
+		      int flags, const char *dev_name, void *data)
+{
+	return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super);
+}
+
+static struct file_system_type hfs_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "hfs",
+	.mount		= hfs_mount,
+	.kill_sb	= kill_block_super,
+	.fs_flags	= FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("hfs");
+
+static void hfs_init_once(void *p)
+{
+	struct hfs_inode_info *i = p;
+
+	inode_init_once(&i->vfs_inode);
+}
+
+static int __init init_hfs_fs(void)
+{
+	int err;
+
+	hfs_inode_cachep = kmem_cache_create("hfs_inode_cache",
+		sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN,
+		hfs_init_once);
+	if (!hfs_inode_cachep)
+		return -ENOMEM;
+	err = register_filesystem(&hfs_fs_type);
+	if (err)
+		kmem_cache_destroy(hfs_inode_cachep);
+	return err;
+}
+
+static void __exit exit_hfs_fs(void)
+{
+	unregister_filesystem(&hfs_fs_type);
+
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(hfs_inode_cachep);
+}
+
+module_init(init_hfs_fs)
+module_exit(exit_hfs_fs)