[mirror_ubuntu-artful-kernel.git] / fs / qnx4 / inode.c

/*
 * 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_destroy_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,
	.destroy_inode	= qnx4_destroy_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 |= MS_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.val[0] = (u32)id;
	buf->f_fsid.val[1] = (u32)(id >> 32);

	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 |= MS_RDONLY;	/* Yup, read-only yet */

	/* 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_readpage(struct file *file, struct page *page)
{
	return block_read_full_page(page,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 = {
	.readpage	= qnx4_readpage,
	.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 = kmem_cache_alloc(qnx4_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void qnx4_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
}

static void qnx4_destroy_inode(struct inode *inode)
{
	call_rcu(&inode->i_rcu, qnx4_i_callback);
}

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
1da177e4 LT	1	/*
	2	* QNX4 file system, Linux implementation.
	3	*
	4	* Version : 0.2.1
	5	*
	6	* Using parts of the xiafs filesystem.
	7	*
	8	* History :
	9	*
	10	* 01-06-1998 by Richard Frowijn : first release.
	11	* 20-06-1998 by Frank Denis : Linux 2.1.99+ support, boot signature, misc.
	12	* 30-06-1998 by Frank Denis : first step to write inodes.
	13	*/
	14
1da177e4	15	#include <linux/module.h>
1da177e4	16	#include <linux/init.h>
964f5369	17	#include <linux/slab.h>
1da177e4	18	#include <linux/highuid.h>
1da177e4 LT	19	#include <linux/pagemap.h>
1da177e4 LT	20	#include <linux/buffer_head.h>
79d25767	21	#include <linux/writeback.h>
964f5369 AV	22	#include <linux/statfs.h>
964f5369 AV	23	#include "qnx4.h"
1da177e4 LT	24
	25	#define QNX4_VERSION 4
	26	#define QNX4_BMNAME ".bitmap"
	27
ee9b6d61	28	static const struct super_operations qnx4_sops;
1da177e4	29
1da177e4 LT	30	static struct inode qnx4_alloc_inode(struct super_block sb);
1da177e4 LT	31	static void qnx4_destroy_inode(struct inode *inode);
1da177e4	32	static int qnx4_remount(struct super_block sb, int flags, char *data);
726c3342	33	static int qnx4_statfs(struct dentry , struct kstatfs );
1da177e4	34
ee9b6d61	35	static const struct super_operations qnx4_sops =
1da177e4 LT	36	{
	37	.alloc_inode = qnx4_alloc_inode,
	38	.destroy_inode = qnx4_destroy_inode,
1da177e4 LT	39	.statfs = qnx4_statfs,
1da177e4 LT	40	.remount_fs = qnx4_remount,
1da177e4 LT	41	};
	42
	43	static int qnx4_remount(struct super_block sb, int flags, char *data)
	44	{
	45	struct qnx4_sb_info *qs;
	46
02b9984d	47	sync_filesystem(sb);
1da177e4 LT	48	qs = qnx4_sb(sb);
1da177e4 LT	49	qs->Version = QNX4_VERSION;
1da177e4	50	*flags \|= MS_RDONLY;
1da177e4 LT	51	return 0;
	52	}
	53
1da177e4 LT	54	static int qnx4_get_block( struct inode inode, sector_t iblock, struct buffer_head bh, int create )
	55	{
	56	unsigned long phys;
	57
891ddb95	58	QNX4DEBUG((KERN_INFO "qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
1da177e4 LT	59
	60	phys = qnx4_block_map( inode, iblock );
	61	if ( phys ) {
	62	// logical block is before EOF
	63	map_bh(bh, inode->i_sb, phys);
1da177e4 LT	64	}
	65	return 0;
	66	}
	67
7cd916f6 AV	68	static inline u32 try_extent(qnx4_xtnt_t extent, u32 offset)
	69	{
	70	u32 size = le32_to_cpu(extent->xtnt_size);
	71	if (*offset < size)
	72	return le32_to_cpu(extent->xtnt_blk) + *offset - 1;
	73	*offset -= size;
	74	return 0;
	75	}
	76
1da177e4 LT	77	unsigned long qnx4_block_map( struct inode *inode, long iblock )
	78	{
	79	int ix;
7cd916f6	80	long i_xblk;
1da177e4 LT	81	struct buffer_head *bh = NULL;
	82	struct qnx4_xblk *xblk = NULL;
	83	struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
75043cb5	84	u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
7cd916f6 AV	85	u32 offset = iblock;
7cd916f6 AV	86	u32 block = try_extent(&qnx4_inode->di_first_xtnt, &offset);
1da177e4	87
7cd916f6	88	if (block) {
1da177e4	89	// iblock is in the first extent. This is easy.
1da177e4 LT	90	} else {
	91	// iblock is beyond first extent. We have to follow the extent chain.
	92	i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
1da177e4 LT	93	ix = 0;
	94	while ( --nxtnt > 0 ) {
	95	if ( ix == 0 ) {
	96	// read next xtnt block.
	97	bh = sb_bread(inode->i_sb, i_xblk - 1);
	98	if ( !bh ) {
891ddb95	99	QNX4DEBUG((KERN_ERR "qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
1da177e4 LT	100	return -EIO;
	101	}
	102	xblk = (struct qnx4_xblk*)bh->b_data;
	103	if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
891ddb95	104	QNX4DEBUG((KERN_ERR "qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
1da177e4 LT	105	return -EIO;
	106	}
	107	}
7cd916f6 AV	108	block = try_extent(&xblk->xblk_xtnts[ix], &offset);
7cd916f6 AV	109	if (block) {
1da177e4	110	// got it!
1da177e4 LT	111	break;
1da177e4 LT	112	}
1da177e4 LT	113	if ( ++ix >= xblk->xblk_num_xtnts ) {
	114	i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
	115	ix = 0;
	116	brelse( bh );
	117	bh = NULL;
	118	}
	119	}
	120	if ( bh )
	121	brelse( bh );
	122	}
	123
891ddb95	124	QNX4DEBUG((KERN_INFO "qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
1da177e4 LT	125	return block;
	126	}
	127
726c3342	128	static int qnx4_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4	129	{
726c3342	130	struct super_block *sb = dentry->d_sb;
5b76dc06	131	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
726c3342	132
1da177e4 LT	133	buf->f_type = sb->s_magic;
	134	buf->f_bsize = sb->s_blocksize;
	135	buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8;
	136	buf->f_bfree = qnx4_count_free_blocks(sb);
	137	buf->f_bavail = buf->f_bfree;
	138	buf->f_namelen = QNX4_NAME_MAX;
5b76dc06 CL	139	buf->f_fsid.val[0] = (u32)id;
5b76dc06 CL	140	buf->f_fsid.val[1] = (u32)(id >> 32);
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;
	201	s->s_magic = QNX4_SUPER_MAGIC;
	202	s->s_flags \|= MS_RDONLY; /* Yup, read-only yet */
	203
1da177e4 LT	204	/* Check the superblock signature. Since the qnx4 code is
	205	dangerous, we should leave as quickly as possible
	206	if we don't belong here... */
	207	bh = sb_bread(s, 1);
	208	if (!bh) {
891ddb95	209	printk(KERN_ERR "qnx4: unable to read the superblock\n");
208adb64	210	return -EINVAL;
1da177e4	211	}
1da177e4 LT	212
1da177e4 LT	213	/* check before allocating dentries, inodes, .. */
208adb64 AV	214	errmsg = qnx4_checkroot(s, (struct qnx4_super_block *) bh->b_data);
208adb64 AV	215	brelse(bh);
1da177e4 LT	216	if (errmsg != NULL) {
1da177e4 LT	217	if (!silent)
891ddb95	218	printk(KERN_ERR "qnx4: %s\n", errmsg);
208adb64	219	return -EINVAL;
1da177e4 LT	220	}
	221
	222	/* does root not have inode number QNX4_ROOT_INO ?? */
2b7e5bcb DH	223	root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
2b7e5bcb DH	224	if (IS_ERR(root)) {
891ddb95	225	printk(KERN_ERR "qnx4: get inode failed\n");
208adb64	226	return PTR_ERR(root);
1da177e4 LT	227	}
1da177e4 LT	228
48fde701	229	s->s_root = d_make_root(root);
1da177e4	230	if (s->s_root == NULL)
208adb64	231	return -ENOMEM;
1da177e4	232
1da177e4	233	return 0;
1da177e4 LT	234	}
1da177e4 LT	235
208adb64	236	static void qnx4_kill_sb(struct super_block *sb)
1da177e4 LT	237	{
1da177e4 LT	238	struct qnx4_sb_info *qs = qnx4_sb(sb);
208adb64 AV	239	kill_block_super(sb);
	240	if (qs) {
	241	kfree(qs->BitMap);
	242	kfree(qs);
	243	}
1da177e4 LT	244	}
1da177e4 LT	245
1da177e4 LT	246	static int qnx4_readpage(struct file file, struct page page)
	247	{
	248	return block_read_full_page(page,qnx4_get_block);
	249	}
f8706184	250
1da177e4 LT	251	static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
	252	{
	253	return generic_block_bmap(mapping,block,qnx4_get_block);
	254	}
f5e54d6e	255	static const struct address_space_operations qnx4_aops = {
1da177e4	256	.readpage = qnx4_readpage,
1da177e4 LT	257	.bmap = qnx4_bmap
	258	};
	259
2b7e5bcb	260	struct inode qnx4_iget(struct super_block sb, unsigned long ino)
1da177e4 LT	261	{
	262	struct buffer_head *bh;
	263	struct qnx4_inode_entry *raw_inode;
2b7e5bcb DH	264	int block;
	265	struct qnx4_inode_entry *qnx4_inode;
	266	struct inode *inode;
1da177e4	267
2b7e5bcb DH	268	inode = iget_locked(sb, ino);
	269	if (!inode)
	270	return ERR_PTR(-ENOMEM);
	271	if (!(inode->i_state & I_NEW))
	272	return inode;
	273
	274	qnx4_inode = qnx4_raw_inode(inode);
1da177e4 LT	275	inode->i_mode = 0;
1da177e4 LT	276
891ddb95	277	QNX4DEBUG((KERN_INFO "reading inode : [%d]\n", ino));
1da177e4	278	if (!ino) {
2b7e5bcb DH	279	printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is "
2b7e5bcb DH	280	"out of range\n",
1da177e4	281	sb->s_id, ino);
2b7e5bcb DH	282	iget_failed(inode);
2b7e5bcb DH	283	return ERR_PTR(-EIO);
1da177e4 LT	284	}
	285	block = ino / QNX4_INODES_PER_BLOCK;
	286
	287	if (!(bh = sb_bread(sb, block))) {
891ddb95	288	printk(KERN_ERR "qnx4: major problem: unable to read inode from dev "
1da177e4	289	"%s\n", sb->s_id);
2b7e5bcb DH	290	iget_failed(inode);
2b7e5bcb DH	291	return ERR_PTR(-EIO);
1da177e4 LT	292	}
	293	raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
	294	(ino % QNX4_INODES_PER_BLOCK);
	295
	296	inode->i_mode = le16_to_cpu(raw_inode->di_mode);
511728d7 EB	297	i_uid_write(inode, (uid_t)le16_to_cpu(raw_inode->di_uid));
511728d7 EB	298	i_gid_write(inode, (gid_t)le16_to_cpu(raw_inode->di_gid));
bfe86848	299	set_nlink(inode, le16_to_cpu(raw_inode->di_nlink));
1da177e4 LT	300	inode->i_size = le32_to_cpu(raw_inode->di_size);
	301	inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime);
	302	inode->i_mtime.tv_nsec = 0;
	303	inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime);
	304	inode->i_atime.tv_nsec = 0;
	305	inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime);
	306	inode->i_ctime.tv_nsec = 0;
	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;
e94b1766	339	ei = kmem_cache_alloc(qnx4_inode_cachep, GFP_KERNEL);
1da177e4 LT	340	if (!ei)
	341	return NULL;
	342	return &ei->vfs_inode;
	343	}
	344
fa0d7e3d	345	static void qnx4_i_callback(struct rcu_head *head)
1da177e4	346	{
fa0d7e3d	347	struct inode *inode = container_of(head, struct inode, i_rcu);
1da177e4 LT	348	kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
	349	}
	350
fa0d7e3d NP	351	static void qnx4_destroy_inode(struct inode *inode)
	352	{
	353	call_rcu(&inode->i_rcu, qnx4_i_callback);
	354	}
	355
51cc5068	356	static void init_once(void *foo)
1da177e4 LT	357	{
	358	struct qnx4_inode_info ei = (struct qnx4_inode_info ) foo;
	359
a35afb83	360	inode_init_once(&ei->vfs_inode);
1da177e4 LT	361	}
	362
	363	static int init_inodecache(void)
	364	{
	365	qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
	366	sizeof(struct qnx4_inode_info),
fffb60f9	367	0, (SLAB_RECLAIM_ACCOUNT\|
5d097056	368	SLAB_MEM_SPREAD\|SLAB_ACCOUNT),
20c2df83	369	init_once);
1da177e4 LT	370	if (qnx4_inode_cachep == NULL)
	371	return -ENOMEM;
	372	return 0;
	373	}
	374
	375	static void destroy_inodecache(void)
	376	{
8c0a8537 KS	377	/*
	378	* Make sure all delayed rcu free inodes are flushed before we
	379	* destroy cache.
	380	*/
	381	rcu_barrier();
1a1d92c1	382	kmem_cache_destroy(qnx4_inode_cachep);
1da177e4 LT	383	}
1da177e4 LT	384
152a0836 AV	385	static struct dentry qnx4_mount(struct file_system_type fs_type,
152a0836 AV	386	int flags, const char dev_name, void data)
1da177e4	387	{
152a0836	388	return mount_bdev(fs_type, flags, dev_name, data, qnx4_fill_super);
1da177e4 LT	389	}
	390
	391	static struct file_system_type qnx4_fs_type = {
	392	.owner = THIS_MODULE,
	393	.name = "qnx4",
152a0836	394	.mount = qnx4_mount,
208adb64	395	.kill_sb = qnx4_kill_sb,
1da177e4 LT	396	.fs_flags = FS_REQUIRES_DEV,
1da177e4 LT	397	};
7f78e035	398	MODULE_ALIAS_FS("qnx4");
1da177e4 LT	399
	400	static int __init init_qnx4_fs(void)
	401	{
	402	int err;
	403
	404	err = init_inodecache();
	405	if (err)
	406	return err;
	407
	408	err = register_filesystem(&qnx4_fs_type);
	409	if (err) {
	410	destroy_inodecache();
	411	return err;
	412	}
	413
891ddb95	414	printk(KERN_INFO "QNX4 filesystem 0.2.3 registered.\n");
1da177e4 LT	415	return 0;
	416	}
	417
	418	static void __exit exit_qnx4_fs(void)
	419	{
	420	unregister_filesystem(&qnx4_fs_type);
	421	destroy_inodecache();
	422	}
	423
	424	module_init(init_qnx4_fs)
	425	module_exit(exit_qnx4_fs)
	426	MODULE_LICENSE("GPL");
	427