[linux.git] / fs / qnx4 / inode.c

// 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_set_mtime(inode, le32_to_cpu(raw_inode->di_mtime), 0);
	inode_set_atime(inode, le32_to_cpu(raw_inode->di_atime), 0);
	inode_set_ctime(inode, le32_to_cpu(raw_inode->di_ctime), 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");
Commit	Line	Data
09c434b8	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* QNX4 file system, Linux implementation.
	4	*
	5	* Version : 0.2.1
	6	*
	7	* Using parts of the xiafs filesystem.
	8	*
	9	* History :
	10	*
	11	* 01-06-1998 by Richard Frowijn : first release.
	12	* 20-06-1998 by Frank Denis : Linux 2.1.99+ support, boot signature, misc.
	13	* 30-06-1998 by Frank Denis : first step to write inodes.
	14	*/
	15
1da177e4	16	#include <linux/module.h>
1da177e4	17	#include <linux/init.h>
964f5369	18	#include <linux/slab.h>
1da177e4	19	#include <linux/highuid.h>
1da177e4 LT	20	#include <linux/pagemap.h>
1da177e4 LT	21	#include <linux/buffer_head.h>
79d25767	22	#include <linux/writeback.h>
964f5369 AV	23	#include <linux/statfs.h>
964f5369 AV	24	#include "qnx4.h"
1da177e4 LT	25
	26	#define QNX4_VERSION 4
	27	#define QNX4_BMNAME ".bitmap"
	28
ee9b6d61	29	static const struct super_operations qnx4_sops;
1da177e4	30
1da177e4	31	static struct inode qnx4_alloc_inode(struct super_block sb);
bc40ddd1	32	static void qnx4_free_inode(struct inode *inode);
1da177e4	33	static int qnx4_remount(struct super_block sb, int flags, char *data);
726c3342	34	static int qnx4_statfs(struct dentry , struct kstatfs );
1da177e4	35
ee9b6d61	36	static const struct super_operations qnx4_sops =
1da177e4 LT	37	{
1da177e4 LT	38	.alloc_inode = qnx4_alloc_inode,
bc40ddd1	39	.free_inode = qnx4_free_inode,
1da177e4 LT	40	.statfs = qnx4_statfs,
1da177e4 LT	41	.remount_fs = qnx4_remount,
1da177e4 LT	42	};
	43
	44	static int qnx4_remount(struct super_block sb, int flags, char *data)
	45	{
	46	struct qnx4_sb_info *qs;
	47
02b9984d	48	sync_filesystem(sb);
1da177e4 LT	49	qs = qnx4_sb(sb);
1da177e4 LT	50	qs->Version = QNX4_VERSION;
1751e8a6	51	*flags \|= SB_RDONLY;
1da177e4 LT	52	return 0;
	53	}
	54
1da177e4 LT	55	static int qnx4_get_block( struct inode inode, sector_t iblock, struct buffer_head bh, int create )
	56	{
	57	unsigned long phys;
	58
891ddb95	59	QNX4DEBUG((KERN_INFO "qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
1da177e4 LT	60
	61	phys = qnx4_block_map( inode, iblock );
	62	if ( phys ) {
	63	// logical block is before EOF
	64	map_bh(bh, inode->i_sb, phys);
1da177e4 LT	65	}
	66	return 0;
	67	}
	68
7cd916f6 AV	69	static inline u32 try_extent(qnx4_xtnt_t extent, u32 offset)
	70	{
	71	u32 size = le32_to_cpu(extent->xtnt_size);
	72	if (*offset < size)
	73	return le32_to_cpu(extent->xtnt_blk) + *offset - 1;
	74	*offset -= size;
	75	return 0;
	76	}
	77
1da177e4 LT	78	unsigned long qnx4_block_map( struct inode *inode, long iblock )
	79	{
	80	int ix;
7cd916f6	81	long i_xblk;
1da177e4 LT	82	struct buffer_head *bh = NULL;
	83	struct qnx4_xblk *xblk = NULL;
	84	struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
75043cb5	85	u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
7cd916f6 AV	86	u32 offset = iblock;
7cd916f6 AV	87	u32 block = try_extent(&qnx4_inode->di_first_xtnt, &offset);
1da177e4	88
7cd916f6	89	if (block) {
1da177e4	90	// iblock is in the first extent. This is easy.
1da177e4 LT	91	} else {
	92	// iblock is beyond first extent. We have to follow the extent chain.
	93	i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
1da177e4 LT	94	ix = 0;
	95	while ( --nxtnt > 0 ) {
	96	if ( ix == 0 ) {
	97	// read next xtnt block.
	98	bh = sb_bread(inode->i_sb, i_xblk - 1);
	99	if ( !bh ) {
891ddb95	100	QNX4DEBUG((KERN_ERR "qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
1da177e4 LT	101	return -EIO;
	102	}
	103	xblk = (struct qnx4_xblk*)bh->b_data;
	104	if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
891ddb95	105	QNX4DEBUG((KERN_ERR "qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
1da177e4 LT	106	return -EIO;
	107	}
	108	}
7cd916f6 AV	109	block = try_extent(&xblk->xblk_xtnts[ix], &offset);
7cd916f6 AV	110	if (block) {
1da177e4	111	// got it!
1da177e4 LT	112	break;
1da177e4 LT	113	}
1da177e4 LT	114	if ( ++ix >= xblk->xblk_num_xtnts ) {
	115	i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
	116	ix = 0;
	117	brelse( bh );
	118	bh = NULL;
	119	}
	120	}
	121	if ( bh )
	122	brelse( bh );
	123	}
	124
891ddb95	125	QNX4DEBUG((KERN_INFO "qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
1da177e4 LT	126	return block;
	127	}
	128
726c3342	129	static int qnx4_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4	130	{
726c3342	131	struct super_block *sb = dentry->d_sb;
5b76dc06	132	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
726c3342	133
1da177e4 LT	134	buf->f_type = sb->s_magic;
	135	buf->f_bsize = sb->s_blocksize;
	136	buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8;
	137	buf->f_bfree = qnx4_count_free_blocks(sb);
	138	buf->f_bavail = buf->f_bfree;
	139	buf->f_namelen = QNX4_NAME_MAX;
6d1349c7	140	buf->f_fsid = u64_to_fsid(id);
1da177e4	141
1da177e4 LT	142	return 0;
	143	}
	144
	145	/*
	146	* Check the root directory of the filesystem to make sure
	147	* it really _is_ a qnx4 filesystem, and to check the size
	148	* of the directory entry.
	149	*/
208adb64 AV	150	static const char qnx4_checkroot(struct super_block sb,
208adb64 AV	151	struct qnx4_super_block *s)
1da177e4 LT	152	{
	153	struct buffer_head *bh;
	154	struct qnx4_inode_entry *rootdir;
	155	int rd, rl;
	156	int i, j;
1da177e4	157
208adb64	158	if (s->RootDir.di_fname[0] != '/' \|\| s->RootDir.di_fname[1] != '\0')
1da177e4	159	return "no qnx4 filesystem (no root dir).";
4134bf81	160	QNX4DEBUG((KERN_NOTICE "QNX4 filesystem found on dev %s.\n", sb->s_id));
208adb64 AV	161	rd = le32_to_cpu(s->RootDir.di_first_xtnt.xtnt_blk) - 1;
208adb64 AV	162	rl = le32_to_cpu(s->RootDir.di_first_xtnt.xtnt_size);
4134bf81 AV	163	for (j = 0; j < rl; j++) {
	164	bh = sb_bread(sb, rd + j); /* root dir, first block */
	165	if (bh == NULL)
	166	return "unable to read root entry.";
	167	rootdir = (struct qnx4_inode_entry *) bh->b_data;
	168	for (i = 0; i < QNX4_INODES_PER_BLOCK; i++, rootdir++) {
	169	QNX4DEBUG((KERN_INFO "rootdir entry found : [%s]\n", rootdir->di_fname));
	170	if (strcmp(rootdir->di_fname, QNX4_BMNAME) != 0)
	171	continue;
	172	qnx4_sb(sb)->BitMap = kmemdup(rootdir,
	173	sizeof(struct qnx4_inode_entry),
	174	GFP_KERNEL);
1da177e4	175	brelse(bh);
4134bf81 AV	176	if (!qnx4_sb(sb)->BitMap)
	177	return "not enough memory for bitmap inode";
	178	/* keep bitmap inode known */
	179	return NULL;
1da177e4	180	}
4134bf81	181	brelse(bh);
1da177e4	182	}
4134bf81	183	return "bitmap file not found.";
1da177e4 LT	184	}
	185
	186	static int qnx4_fill_super(struct super_block s, void data, int silent)
	187	{
	188	struct buffer_head *bh;
	189	struct inode *root;
	190	const char *errmsg;
	191	struct qnx4_sb_info *qs;
	192
f8314dc6	193	qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
073c2141	194	if (!qs)
1da177e4 LT	195	return -ENOMEM;
1da177e4 LT	196	s->s_fs_info = qs;
1da177e4 LT	197
	198	sb_set_blocksize(s, QNX4_BLOCK_SIZE);
	199
208adb64 AV	200	s->s_op = &qnx4_sops;
208adb64 AV	201	s->s_magic = QNX4_SUPER_MAGIC;
1751e8a6	202	s->s_flags \|= SB_RDONLY; /* Yup, read-only yet */
22b13969 DD	203	s->s_time_min = 0;
22b13969 DD	204	s->s_time_max = U32_MAX;
208adb64	205
1da177e4 LT	206	/* Check the superblock signature. Since the qnx4 code is
	207	dangerous, we should leave as quickly as possible
	208	if we don't belong here... */
	209	bh = sb_bread(s, 1);
	210	if (!bh) {
891ddb95	211	printk(KERN_ERR "qnx4: unable to read the superblock\n");
208adb64	212	return -EINVAL;
1da177e4	213	}
1da177e4 LT	214
1da177e4 LT	215	/* check before allocating dentries, inodes, .. */
208adb64 AV	216	errmsg = qnx4_checkroot(s, (struct qnx4_super_block *) bh->b_data);
208adb64 AV	217	brelse(bh);
1da177e4 LT	218	if (errmsg != NULL) {
1da177e4 LT	219	if (!silent)
891ddb95	220	printk(KERN_ERR "qnx4: %s\n", errmsg);
208adb64	221	return -EINVAL;
1da177e4 LT	222	}
	223
	224	/* does root not have inode number QNX4_ROOT_INO ?? */
2b7e5bcb DH	225	root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
2b7e5bcb DH	226	if (IS_ERR(root)) {
891ddb95	227	printk(KERN_ERR "qnx4: get inode failed\n");
208adb64	228	return PTR_ERR(root);
1da177e4 LT	229	}
1da177e4 LT	230
48fde701	231	s->s_root = d_make_root(root);
1da177e4	232	if (s->s_root == NULL)
208adb64	233	return -ENOMEM;
1da177e4	234
1da177e4	235	return 0;
1da177e4 LT	236	}
1da177e4 LT	237
208adb64	238	static void qnx4_kill_sb(struct super_block *sb)
1da177e4 LT	239	{
1da177e4 LT	240	struct qnx4_sb_info *qs = qnx4_sb(sb);
208adb64 AV	241	kill_block_super(sb);
	242	if (qs) {
	243	kfree(qs->BitMap);
	244	kfree(qs);
	245	}
1da177e4 LT	246	}
1da177e4 LT	247
2c69e205	248	static int qnx4_read_folio(struct file file, struct folio folio)
1da177e4	249	{
2c69e205	250	return block_read_full_folio(folio, qnx4_get_block);
1da177e4	251	}
f8706184	252
1da177e4 LT	253	static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
	254	{
	255	return generic_block_bmap(mapping,block,qnx4_get_block);
	256	}
2c69e205	257
f5e54d6e	258	static const struct address_space_operations qnx4_aops = {
2c69e205	259	.read_folio = qnx4_read_folio,
1da177e4 LT	260	.bmap = qnx4_bmap
	261	};
	262
2b7e5bcb	263	struct inode qnx4_iget(struct super_block sb, unsigned long ino)
1da177e4 LT	264	{
	265	struct buffer_head *bh;
	266	struct qnx4_inode_entry *raw_inode;
2b7e5bcb DH	267	int block;
	268	struct qnx4_inode_entry *qnx4_inode;
	269	struct inode *inode;
1da177e4	270
2b7e5bcb DH	271	inode = iget_locked(sb, ino);
	272	if (!inode)
	273	return ERR_PTR(-ENOMEM);
	274	if (!(inode->i_state & I_NEW))
	275	return inode;
	276
	277	qnx4_inode = qnx4_raw_inode(inode);
1da177e4 LT	278	inode->i_mode = 0;
1da177e4 LT	279
891ddb95	280	QNX4DEBUG((KERN_INFO "reading inode : [%d]\n", ino));
1da177e4	281	if (!ino) {
2b7e5bcb DH	282	printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is "
2b7e5bcb DH	283	"out of range\n",
1da177e4	284	sb->s_id, ino);
2b7e5bcb DH	285	iget_failed(inode);
2b7e5bcb DH	286	return ERR_PTR(-EIO);
1da177e4 LT	287	}
	288	block = ino / QNX4_INODES_PER_BLOCK;
	289
	290	if (!(bh = sb_bread(sb, block))) {
891ddb95	291	printk(KERN_ERR "qnx4: major problem: unable to read inode from dev "
1da177e4	292	"%s\n", sb->s_id);
2b7e5bcb DH	293	iget_failed(inode);
2b7e5bcb DH	294	return ERR_PTR(-EIO);
1da177e4 LT	295	}
	296	raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
	297	(ino % QNX4_INODES_PER_BLOCK);
	298
	299	inode->i_mode = le16_to_cpu(raw_inode->di_mode);
511728d7 EB	300	i_uid_write(inode, (uid_t)le16_to_cpu(raw_inode->di_uid));
511728d7 EB	301	i_gid_write(inode, (gid_t)le16_to_cpu(raw_inode->di_gid));
bfe86848	302	set_nlink(inode, le16_to_cpu(raw_inode->di_nlink));
1da177e4	303	inode->i_size = le32_to_cpu(raw_inode->di_size);
55a75654 JL	304	inode_set_mtime(inode, le32_to_cpu(raw_inode->di_mtime), 0);
55a75654 JL	305	inode_set_atime(inode, le32_to_cpu(raw_inode->di_atime), 0);
bbe21298	306	inode_set_ctime(inode, le32_to_cpu(raw_inode->di_ctime), 0);
1da177e4	307	inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
1da177e4 LT	308
	309	memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE);
	310	if (S_ISREG(inode->i_mode)) {
945ffe54	311	inode->i_fop = &generic_ro_fops;
1da177e4 LT	312	inode->i_mapping->a_ops = &qnx4_aops;
	313	qnx4_i(inode)->mmu_private = inode->i_size;
	314	} else if (S_ISDIR(inode->i_mode)) {
	315	inode->i_op = &qnx4_dir_inode_operations;
	316	inode->i_fop = &qnx4_dir_operations;
	317	} else if (S_ISLNK(inode->i_mode)) {
	318	inode->i_op = &page_symlink_inode_operations;
21fc61c7	319	inode_nohighmem(inode);
1da177e4 LT	320	inode->i_mapping->a_ops = &qnx4_aops;
1da177e4 LT	321	qnx4_i(inode)->mmu_private = inode->i_size;
2b7e5bcb DH	322	} else {
	323	printk(KERN_ERR "qnx4: bad inode %lu on dev %s\n",
	324	ino, sb->s_id);
	325	iget_failed(inode);
	326	brelse(bh);
	327	return ERR_PTR(-EIO);
	328	}
1da177e4	329	brelse(bh);
2b7e5bcb DH	330	unlock_new_inode(inode);
2b7e5bcb DH	331	return inode;
1da177e4 LT	332	}
1da177e4 LT	333
e18b890b	334	static struct kmem_cache *qnx4_inode_cachep;
1da177e4 LT	335
	336	static struct inode qnx4_alloc_inode(struct super_block sb)
	337	{
	338	struct qnx4_inode_info *ei;
fd60b288	339	ei = alloc_inode_sb(sb, qnx4_inode_cachep, GFP_KERNEL);
1da177e4 LT	340	if (!ei)
	341	return NULL;
	342	return &ei->vfs_inode;
	343	}
	344
bc40ddd1	345	static void qnx4_free_inode(struct inode *inode)
1da177e4 LT	346	{
	347	kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
	348	}
	349
51cc5068	350	static void init_once(void *foo)
1da177e4 LT	351	{
	352	struct qnx4_inode_info ei = (struct qnx4_inode_info ) foo;
	353
a35afb83	354	inode_init_once(&ei->vfs_inode);
1da177e4 LT	355	}
	356
	357	static int init_inodecache(void)
	358	{
	359	qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
	360	sizeof(struct qnx4_inode_info),
fffb60f9	361	0, (SLAB_RECLAIM_ACCOUNT\|
5d097056	362	SLAB_MEM_SPREAD\|SLAB_ACCOUNT),
20c2df83	363	init_once);
1da177e4 LT	364	if (qnx4_inode_cachep == NULL)
	365	return -ENOMEM;
	366	return 0;
	367	}
	368
	369	static void destroy_inodecache(void)
	370	{
8c0a8537 KS	371	/*
	372	* Make sure all delayed rcu free inodes are flushed before we
	373	* destroy cache.
	374	*/
	375	rcu_barrier();
1a1d92c1	376	kmem_cache_destroy(qnx4_inode_cachep);
1da177e4 LT	377	}
1da177e4 LT	378
152a0836 AV	379	static struct dentry qnx4_mount(struct file_system_type fs_type,
152a0836 AV	380	int flags, const char dev_name, void data)
1da177e4	381	{
152a0836	382	return mount_bdev(fs_type, flags, dev_name, data, qnx4_fill_super);
1da177e4 LT	383	}
	384
	385	static struct file_system_type qnx4_fs_type = {
	386	.owner = THIS_MODULE,
	387	.name = "qnx4",
152a0836	388	.mount = qnx4_mount,
208adb64	389	.kill_sb = qnx4_kill_sb,
1da177e4 LT	390	.fs_flags = FS_REQUIRES_DEV,
1da177e4 LT	391	};
7f78e035	392	MODULE_ALIAS_FS("qnx4");
1da177e4 LT	393
	394	static int __init init_qnx4_fs(void)
	395	{
	396	int err;
	397
	398	err = init_inodecache();
	399	if (err)
	400	return err;
	401
	402	err = register_filesystem(&qnx4_fs_type);
	403	if (err) {
	404	destroy_inodecache();
	405	return err;
	406	}
	407
891ddb95	408	printk(KERN_INFO "QNX4 filesystem 0.2.3 registered.\n");
1da177e4 LT	409	return 0;
	410	}
	411
	412	static void __exit exit_qnx4_fs(void)
	413	{
	414	unregister_filesystem(&qnx4_fs_type);
	415	destroy_inodecache();
	416	}
	417
	418	module_init(init_qnx4_fs)
	419	module_exit(exit_qnx4_fs)
	420	MODULE_LICENSE("GPL");
	421