1 files changed, 424 insertions, 0 deletions

diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c
new file mode 100644
index 000000000..391ea4029
--- /dev/null
+++ b/fs/qnx4/inode.c
@@ -0,0 +1,424 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * QNX4 file system, Linux implementation.
+ *
+ * Version : 0.2.1
+ *
+ * Using parts of the xiafs filesystem.
+ *
+ * History :
+ *
+ * 01-06-1998 by Richard Frowijn : first release.
+ * 20-06-1998 by Frank Denis : Linux 2.1.99+ support, boot signature, misc.
+ * 30-06-1998 by Frank Denis : first step to write inodes.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/highuid.h>
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+#include <linux/writeback.h>
+#include <linux/statfs.h>
+#include "qnx4.h"
+
+#define QNX4_VERSION  4
+#define QNX4_BMNAME   ".bitmap"
+
+static const struct super_operations qnx4_sops;
+
+static struct inode *qnx4_alloc_inode(struct super_block *sb);
+static void qnx4_free_inode(struct inode *inode);
+static int qnx4_remount(struct super_block *sb, int *flags, char *data);
+static int qnx4_statfs(struct dentry *, struct kstatfs *);
+
+static const struct super_operations qnx4_sops =
+{
+	.alloc_inode	= qnx4_alloc_inode,
+	.free_inode	= qnx4_free_inode,
+	.statfs		= qnx4_statfs,
+	.remount_fs	= qnx4_remount,
+};
+
+static int qnx4_remount(struct super_block *sb, int *flags, char *data)
+{
+	struct qnx4_sb_info *qs;
+
+	sync_filesystem(sb);
+	qs = qnx4_sb(sb);
+	qs->Version = QNX4_VERSION;
+	*flags |= SB_RDONLY;
+	return 0;
+}
+
+static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create )
+{
+	unsigned long phys;
+
+	QNX4DEBUG((KERN_INFO "qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
+
+	phys = qnx4_block_map( inode, iblock );
+	if ( phys ) {
+		// logical block is before EOF
+		map_bh(bh, inode->i_sb, phys);
+	}
+	return 0;
+}
+
+static inline u32 try_extent(qnx4_xtnt_t *extent, u32 *offset)
+{
+	u32 size = le32_to_cpu(extent->xtnt_size);
+	if (*offset < size)
+		return le32_to_cpu(extent->xtnt_blk) + *offset - 1;
+	*offset -= size;
+	return 0;
+}
+
+unsigned long qnx4_block_map( struct inode *inode, long iblock )
+{
+	int ix;
+	long i_xblk;
+	struct buffer_head *bh = NULL;
+	struct qnx4_xblk *xblk = NULL;
+	struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
+	u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
+	u32 offset = iblock;
+	u32 block = try_extent(&qnx4_inode->di_first_xtnt, &offset);
+
+	if (block) {
+		// iblock is in the first extent. This is easy.
+	} else {
+		// iblock is beyond first extent. We have to follow the extent chain.
+		i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
+		ix = 0;
+		while ( --nxtnt > 0 ) {
+			if ( ix == 0 ) {
+				// read next xtnt block.
+				bh = sb_bread(inode->i_sb, i_xblk - 1);
+				if ( !bh ) {
+					QNX4DEBUG((KERN_ERR "qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
+					return -EIO;
+				}
+				xblk = (struct qnx4_xblk*)bh->b_data;
+				if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
+					QNX4DEBUG((KERN_ERR "qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
+					return -EIO;
+				}
+			}
+			block = try_extent(&xblk->xblk_xtnts[ix], &offset);
+			if (block) {
+				// got it!
+				break;
+			}
+			if ( ++ix >= xblk->xblk_num_xtnts ) {
+				i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
+				ix = 0;
+				brelse( bh );
+				bh = NULL;
+			}
+		}
+		if ( bh )
+			brelse( bh );
+	}
+
+	QNX4DEBUG((KERN_INFO "qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
+	return block;
+}
+
+static int qnx4_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    = sb->s_magic;
+	buf->f_bsize   = sb->s_blocksize;
+	buf->f_blocks  = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8;
+	buf->f_bfree   = qnx4_count_free_blocks(sb);
+	buf->f_bavail  = buf->f_bfree;
+	buf->f_namelen = QNX4_NAME_MAX;
+	buf->f_fsid    = u64_to_fsid(id);
+
+	return 0;
+}
+
+/*
+ * Check the root directory of the filesystem to make sure
+ * it really _is_ a qnx4 filesystem, and to check the size
+ * of the directory entry.
+ */
+static const char *qnx4_checkroot(struct super_block *sb,
+				  struct qnx4_super_block *s)
+{
+	struct buffer_head *bh;
+	struct qnx4_inode_entry *rootdir;
+	int rd, rl;
+	int i, j;
+
+	if (s->RootDir.di_fname[0] != '/' || s->RootDir.di_fname[1] != '\0')
+		return "no qnx4 filesystem (no root dir).";
+	QNX4DEBUG((KERN_NOTICE "QNX4 filesystem found on dev %s.\n", sb->s_id));
+	rd = le32_to_cpu(s->RootDir.di_first_xtnt.xtnt_blk) - 1;
+	rl = le32_to_cpu(s->RootDir.di_first_xtnt.xtnt_size);
+	for (j = 0; j < rl; j++) {
+		bh = sb_bread(sb, rd + j);	/* root dir, first block */
+		if (bh == NULL)
+			return "unable to read root entry.";
+		rootdir = (struct qnx4_inode_entry *) bh->b_data;
+		for (i = 0; i < QNX4_INODES_PER_BLOCK; i++, rootdir++) {
+			QNX4DEBUG((KERN_INFO "rootdir entry found : [%s]\n", rootdir->di_fname));
+			if (strcmp(rootdir->di_fname, QNX4_BMNAME) != 0)
+				continue;
+			qnx4_sb(sb)->BitMap = kmemdup(rootdir,
+						      sizeof(struct qnx4_inode_entry),
+						      GFP_KERNEL);
+			brelse(bh);
+			if (!qnx4_sb(sb)->BitMap)
+				return "not enough memory for bitmap inode";
+			/* keep bitmap inode known */
+			return NULL;
+		}
+		brelse(bh);
+	}
+	return "bitmap file not found.";
+}
+
+static int qnx4_fill_super(struct super_block *s, void *data, int silent)
+{
+	struct buffer_head *bh;
+	struct inode *root;
+	const char *errmsg;
+	struct qnx4_sb_info *qs;
+
+	qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
+	if (!qs)
+		return -ENOMEM;
+	s->s_fs_info = qs;
+
+	sb_set_blocksize(s, QNX4_BLOCK_SIZE);
+
+	s->s_op = &qnx4_sops;
+	s->s_magic = QNX4_SUPER_MAGIC;
+	s->s_flags |= SB_RDONLY;	/* Yup, read-only yet */
+	s->s_time_min = 0;
+	s->s_time_max = U32_MAX;
+
+	/* Check the superblock signature. Since the qnx4 code is
+	   dangerous, we should leave as quickly as possible
+	   if we don't belong here... */
+	bh = sb_bread(s, 1);
+	if (!bh) {
+		printk(KERN_ERR "qnx4: unable to read the superblock\n");
+		return -EINVAL;
+	}
+
+ 	/* check before allocating dentries, inodes, .. */
+	errmsg = qnx4_checkroot(s, (struct qnx4_super_block *) bh->b_data);
+	brelse(bh);
+	if (errmsg != NULL) {
+ 		if (!silent)
+			printk(KERN_ERR "qnx4: %s\n", errmsg);
+		return -EINVAL;
+	}
+
+ 	/* does root not have inode number QNX4_ROOT_INO ?? */
+	root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
+	if (IS_ERR(root)) {
+		printk(KERN_ERR "qnx4: get inode failed\n");
+		return PTR_ERR(root);
+ 	}
+
+ 	s->s_root = d_make_root(root);
+ 	if (s->s_root == NULL)
+ 		return -ENOMEM;
+
+	return 0;
+}
+
+static void qnx4_kill_sb(struct super_block *sb)
+{
+	struct qnx4_sb_info *qs = qnx4_sb(sb);
+	kill_block_super(sb);
+	if (qs) {
+		kfree(qs->BitMap);
+		kfree(qs);
+	}
+}
+
+static int qnx4_read_folio(struct file *file, struct folio *folio)
+{
+	return block_read_full_folio(folio, qnx4_get_block);
+}
+
+static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
+{
+	return generic_block_bmap(mapping,block,qnx4_get_block);
+}
+
+static const struct address_space_operations qnx4_aops = {
+	.read_folio	= qnx4_read_folio,
+	.bmap		= qnx4_bmap
+};
+
+struct inode *qnx4_iget(struct super_block *sb, unsigned long ino)
+{
+	struct buffer_head *bh;
+	struct qnx4_inode_entry *raw_inode;
+	int block;
+	struct qnx4_inode_entry *qnx4_inode;
+	struct inode *inode;
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	qnx4_inode = qnx4_raw_inode(inode);
+	inode->i_mode = 0;
+
+	QNX4DEBUG((KERN_INFO "reading inode : [%d]\n", ino));
+	if (!ino) {
+		printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is "
+				"out of range\n",
+		       sb->s_id, ino);
+		iget_failed(inode);
+		return ERR_PTR(-EIO);
+	}
+	block = ino / QNX4_INODES_PER_BLOCK;
+
+	if (!(bh = sb_bread(sb, block))) {
+		printk(KERN_ERR "qnx4: major problem: unable to read inode from dev "
+		       "%s\n", sb->s_id);
+		iget_failed(inode);
+		return ERR_PTR(-EIO);
+	}
+	raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
+	    (ino % QNX4_INODES_PER_BLOCK);
+
+	inode->i_mode    = le16_to_cpu(raw_inode->di_mode);
+	i_uid_write(inode, (uid_t)le16_to_cpu(raw_inode->di_uid));
+	i_gid_write(inode, (gid_t)le16_to_cpu(raw_inode->di_gid));
+	set_nlink(inode, le16_to_cpu(raw_inode->di_nlink));
+	inode->i_size    = le32_to_cpu(raw_inode->di_size);
+	inode->i_mtime.tv_sec   = le32_to_cpu(raw_inode->di_mtime);
+	inode->i_mtime.tv_nsec = 0;
+	inode->i_atime.tv_sec   = le32_to_cpu(raw_inode->di_atime);
+	inode->i_atime.tv_nsec = 0;
+	inode->i_ctime.tv_sec   = le32_to_cpu(raw_inode->di_ctime);
+	inode->i_ctime.tv_nsec = 0;
+	inode->i_blocks  = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
+
+	memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE);
+	if (S_ISREG(inode->i_mode)) {
+		inode->i_fop = &generic_ro_fops;
+		inode->i_mapping->a_ops = &qnx4_aops;
+		qnx4_i(inode)->mmu_private = inode->i_size;
+	} else if (S_ISDIR(inode->i_mode)) {
+		inode->i_op = &qnx4_dir_inode_operations;
+		inode->i_fop = &qnx4_dir_operations;
+	} else if (S_ISLNK(inode->i_mode)) {
+		inode->i_op = &page_symlink_inode_operations;
+		inode_nohighmem(inode);
+		inode->i_mapping->a_ops = &qnx4_aops;
+		qnx4_i(inode)->mmu_private = inode->i_size;
+	} else {
+		printk(KERN_ERR "qnx4: bad inode %lu on dev %s\n",
+			ino, sb->s_id);
+		iget_failed(inode);
+		brelse(bh);
+		return ERR_PTR(-EIO);
+	}
+	brelse(bh);
+	unlock_new_inode(inode);
+	return inode;
+}
+
+static struct kmem_cache *qnx4_inode_cachep;
+
+static struct inode *qnx4_alloc_inode(struct super_block *sb)
+{
+	struct qnx4_inode_info *ei;
+	ei = alloc_inode_sb(sb, qnx4_inode_cachep, GFP_KERNEL);
+	if (!ei)
+		return NULL;
+	return &ei->vfs_inode;
+}
+
+static void qnx4_free_inode(struct inode *inode)
+{
+	kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
+}
+
+static void init_once(void *foo)
+{
+	struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo;
+
+	inode_init_once(&ei->vfs_inode);
+}
+
+static int init_inodecache(void)
+{
+	qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
+					     sizeof(struct qnx4_inode_info),
+					     0, (SLAB_RECLAIM_ACCOUNT|
+						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
+					     init_once);
+	if (qnx4_inode_cachep == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+static void destroy_inodecache(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(qnx4_inode_cachep);
+}
+
+static struct dentry *qnx4_mount(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data)
+{
+	return mount_bdev(fs_type, flags, dev_name, data, qnx4_fill_super);
+}
+
+static struct file_system_type qnx4_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "qnx4",
+	.mount		= qnx4_mount,
+	.kill_sb	= qnx4_kill_sb,
+	.fs_flags	= FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("qnx4");
+
+static int __init init_qnx4_fs(void)
+{
+	int err;
+
+	err = init_inodecache();
+	if (err)
+		return err;
+
+	err = register_filesystem(&qnx4_fs_type);
+	if (err) {
+		destroy_inodecache();
+		return err;
+	}
+
+	printk(KERN_INFO "QNX4 filesystem 0.2.3 registered.\n");
+	return 0;
+}
+
+static void __exit exit_qnx4_fs(void)
+{
+	unregister_filesystem(&qnx4_fs_type);
+	destroy_inodecache();
+}
+
+module_init(init_qnx4_fs)
+module_exit(exit_qnx4_fs)
+MODULE_LICENSE("GPL");
+