text: /*
   *	fs/bfs/inode.c
   *	BFS superblock and inode operations.
   *	Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
   *	From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
   */
  
  #include <linux/module.h>
  #include <linux/mm.h>
  #include <linux/slab.h>
  #include <linux/init.h>
  #include <linux/locks.h>
  #include <linux/bfs_fs.h>
  #include <linux/smp_lock.h>
  
  #include <asm/uaccess.h>
  
  #include "bfs_defs.h"
  
  MODULE_AUTHOR("Tigran A. Aivazian <tigran@veritas.com>");
  MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
  MODULE_LICENSE("GPL");
  EXPORT_NO_SYMBOLS;
  
  #undef DEBUG
  
  #ifdef DEBUG
  #define dprintf(x...)	printf(x)
  #else
  #define dprintf(x...)
  #endif
  
  void dump_imap(const char *prefix, struct super_block * s);
  
  static void bfs_read_inode(struct inode * inode)
  {
  	unsigned long ino = inode->i_ino;
  	kdev_t dev = inode->i_dev;
  	struct bfs_inode * di;
  	struct buffer_head * bh;
  	int block, off;
  
  	if (ino < BFS_ROOT_INO || ino > inode->i_sb->su_lasti) {
  		printf("Bad inode number %s:%08lx\n", bdevname(dev), ino);
  		make_bad_inode(inode);
  		return;
  	}
  
  	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
  	bh = sb_bread(inode->i_sb, block);
  	if (!bh) {
  		printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
  		make_bad_inode(inode);
  		return;
  	}
  
  	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
  	di = (struct bfs_inode *)bh->b_data + off;
  
  	inode->i_mode = 0x0000FFFF & di->i_mode;
  	if (di->i_vtype == BFS_VDIR) {
  		inode->i_mode |= S_IFDIR;
  		inode->i_op = &bfs_dir_inops;
  		inode->i_fop = &bfs_dir_operations;
  	} else if (di->i_vtype == BFS_VREG) {
  		inode->i_mode |= S_IFREG;
  		inode->i_op = &bfs_file_inops;
  		inode->i_fop = &bfs_file_operations;
  		inode->i_mapping->a_ops = &bfs_aops;
  	}
  
  	inode->i_uid = di->i_uid;
  	inode->i_gid = di->i_gid;
  	inode->i_nlink = di->i_nlink;
  	inode->i_size = BFS_FILESIZE(di);
  	inode->i_blocks = BFS_FILEBLOCKS(di);
  	inode->i_blksize = PAGE_SIZE;
  	inode->i_atime = di->i_atime;
  	inode->i_mtime = di->i_mtime;
  	inode->i_ctime = di->i_ctime;
  	inode->iu_dsk_ino = di->i_ino; /* can be 0 so we store a copy */
  	inode->iu_sblock = di->i_sblock;
  	inode->iu_eblock = di->i_eblock;
  
  	brelse(bh);
  }
  
  static void bfs_write_inode(struct inode * inode, int unused)
  {
  	unsigned long ino = inode->i_ino;
  	kdev_t dev = inode->i_dev;
  	struct bfs_inode * di;
  	struct buffer_head * bh;
  	int block, off;
  
  	if (ino < BFS_ROOT_INO || ino > inode->i_sb->su_lasti) {
  		printf("Bad inode number %s:%08lx\n", bdevname(dev), ino);
  		return;
  	}
  
  	lock_kernel();
  	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
  	bh = sb_bread(inode->i_sb, block);
  	if (!bh) {
  		printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
  		unlock_kernel();
  		return;
  	}
  
  	off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
  	di = (struct bfs_inode *)bh->b_data + off;
  
  	if (inode->i_ino == BFS_ROOT_INO)
  		di->i_vtype = BFS_VDIR;
  	else
  		di->i_vtype = BFS_VREG;
  
  	di->i_ino = inode->i_ino;
  	di->i_mode = inode->i_mode;
  	di->i_uid = inode->i_uid;
  	di->i_gid = inode->i_gid;
  	di->i_nlink = inode->i_nlink;
  	di->i_atime = inode->i_atime;
  	di->i_mtime = inode->i_mtime;
  	di->i_ctime = inode->i_ctime;
  	di->i_sblock = inode->iu_sblock;
  	di->i_eblock = inode->iu_eblock;
  	di->i_eoffset = di->i_sblock * BFS_BSIZE + inode->i_size - 1;
  
  	mark_buffer_dirty(bh);
  	brelse(bh);
  	unlock_kernel();
  }
  
  static void bfs_delete_inode(struct inode * inode)
  {
  	unsigned long ino = inode->i_ino;
  	kdev_t dev = inode->i_dev;
  	struct bfs_inode * di;
  	struct buffer_head * bh;
  	int block, off;
  	struct super_block * s = inode->i_sb;
  
  	dprintf("ino=%08lx\n", inode->i_ino);
  
  	if (inode->i_ino < BFS_ROOT_INO || inode->i_ino > inode->i_sb->su_lasti) {
  		printf("invalid ino=%08lx\n", inode->i_ino);
  		return;
  	}
  	
  	inode->i_size = 0;
  	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
  	lock_kernel();
  	mark_inode_dirty(inode);
  	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
  	bh = sb_bread(s, block);
  	if (!bh) {
  		printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
  		unlock_kernel();
  		return;
  	}
  	off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
  	di = (struct bfs_inode *)bh->b_data + off;
  	if (di->i_ino) {
  		s->su_freeb += BFS_FILEBLOCKS(di);
  		s->su_freei++;
  		clear_bit(di->i_ino, s->su_imap);
  		dump_imap("delete_inode", s);
  	}
  	di->i_ino = 0;
  	di->i_sblock = 0;
  	mark_buffer_dirty(bh);
  	brelse(bh);
  
  	/* if this was the last file, make the previous 
  	   block "last files last block" even if there is no real file there,
  	   saves us 1 gap */
  	if (s->su_lf_eblk == inode->iu_eblock) {
  		s->su_lf_eblk = inode->iu_sblock - 1;
  		mark_buffer_dirty(s->su_sbh);
  	}
  	unlock_kernel();
  	clear_inode(inode);
  }
  
  static void bfs_put_super(struct super_block *s)
  {
  	brelse(s->su_sbh);
  	kfree(s->su_imap);
  }
  
  static int bfs_statfs(struct super_block *s, struct statfs *buf)
  {
  	buf->f_type = BFS_MAGIC;
  	buf->f_bsize = s->s_blocksize;
  	buf->f_blocks = s->su_blocks;
  	buf->f_bfree = buf->f_bavail = s->su_freeb;
  	buf->f_files = s->su_lasti + 1 - BFS_ROOT_INO;
  	buf->f_ffree = s->su_freei;
  	buf->f_fsid.val[0] = kdev_t_to_nr(s->s_dev);
  	buf->f_namelen = BFS_NAMELEN;
  	return 0;
  }
  
  static void bfs_write_super(struct super_block *s)
  {
  	if (!(s->s_flags & MS_RDONLY))
  		mark_buffer_dirty(s->su_sbh);
  	s->s_dirt = 0;
  }
  
  static struct super_operations bfs_sops = {
  	read_inode:	bfs_read_inode,
  	write_inode:	bfs_write_inode,
  	delete_inode:	bfs_delete_inode,
  	put_super:	bfs_put_super,
  	write_super:	bfs_write_super,
  	statfs:		bfs_statfs,
  };
  
  void dump_imap(const char *prefix, struct super_block * s)
  {
  }
  
  static struct super_block * bfs_read_super(struct super_block * s, 
  	void * data, int silent)
  {
  	kdev_t dev;
  	struct buffer_head * bh;
  	struct bfs_super_block * bfs_sb;
  	struct inode * inode;
  	int i, imap_len;
  
  	dev = s->s_dev;
  	set_blocksize(dev, BFS_BSIZE);
  	s->s_blocksize = BFS_BSIZE;
  	s->s_blocksize_bits = BFS_BSIZE_BITS;
  
  	bh = sb_bread(s, 0);
  	if(!bh)
  		goto out;
  	bfs_sb = (struct bfs_super_block *)bh->b_data;
  	if (bfs_sb->s_magic != BFS_MAGIC) {
  		if (!silent)
  			printf("No BFS filesystem on %s (magic=%08x)\n", 
  				bdevname(dev), bfs_sb->s_magic);
  		goto out;
  	}
  	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
  		printf("%s is unclean, continuing\n", bdevname(dev));
  
  	s->s_magic = BFS_MAGIC;
  	s->su_bfs_sb = bfs_sb;
  	s->su_sbh = bh;
  	s->su_lasti = (bfs_sb->s_start - BFS_BSIZE)/sizeof(struct bfs_inode) 
  			+ BFS_ROOT_INO - 1;
  
  	imap_len = s->su_lasti/8 + 1;
  	s->su_imap = kmalloc(imap_len, GFP_KERNEL);
  	if (!s->su_imap)
  		goto out;
  	memset(s->su_imap, 0, imap_len);
  	for (i=0; i<BFS_ROOT_INO; i++) 
  		set_bit(i, s->su_imap);
  
  	s->s_op = &bfs_sops;
  	inode = iget(s, BFS_ROOT_INO);
  	if (!inode) {
  		kfree(s->su_imap);
  		goto out;
  	}
  	s->s_root = d_alloc_root(inode);
  	if (!s->s_root) {
  		iput(inode);
  		kfree(s->su_imap);
  		goto out;
  	}
  
  	s->su_blocks = (bfs_sb->s_end + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
  	s->su_freeb = (bfs_sb->s_end + 1 - bfs_sb->s_start)>>BFS_BSIZE_BITS;
  	s->su_freei = 0;
  	s->su_lf_eblk = 0;
  	s->su_lf_sblk = 0;
  	s->su_lf_ioff = 0;
  	for (i=BFS_ROOT_INO; i<=s->su_lasti; i++) {
  		inode = iget(s,i);
  		if (inode->iu_dsk_ino == 0)
  			s->su_freei++;
  		else {
  			set_bit(i, s->su_imap);
  			s->su_freeb -= inode->i_blocks;
  			if (inode->iu_eblock > s->su_lf_eblk) {
  				s->su_lf_eblk = inode->iu_eblock;
  				s->su_lf_sblk = inode->iu_sblock;
  				s->su_lf_ioff = BFS_INO2OFF(i);
  			}
  		}
  		iput(inode);
  	}
  	if (!(s->s_flags & MS_RDONLY)) {
  		mark_buffer_dirty(bh);
  		s->s_dirt = 1;
  	} 
  	dump_imap("read_super", s);
  	return s;
  
  out:
  	brelse(bh);
  	return NULL;
  }
  
  static DECLARE_FSTYPE_DEV(bfs_fs_type, "bfs", bfs_read_super);
  
  static int __init init_bfs_fs(void)
  {
  	return register_filesystem(&bfs_fs_type);
  }
  
  static void __exit exit_bfs_fs(void)
  {
  	unregister_filesystem(&bfs_fs_type);
  }
  
  module_init(init_bfs_fs)
  module_exit(exit_bfs_fs)
  