text: /*
   *  linux/fs/affs/inode.c
   *
   *  (c) 1996  Hans-Joachim Widmaier - Rewritten
   *
   *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
   *
   *  (C) 1992  Eric Youngdale Modified for ISO9660 filesystem.
   *
   *  (C) 1991  Linus Torvalds - minix filesystem
   */
  
  #include "affs.h"
  
  extern struct inode_operations affs_symlink_inode_operations;
  extern struct timezone sys_tz;
  
  void
  affs_read_inode(struct inode *inode)
  {
  	struct super_block	*sb = inode->i_sb;
  	struct affs_sb_info	*sbi = AFFS_SB(sb);
  	struct buffer_head	*bh;
  	struct affs_head	*head;
  	struct affs_tail	*tail;
  	u32			 block;
  	u32			 size;
  	u32			 prot;
  	u16			 id;
  
  	pr_debug("AFFS: read_inode(%lu)\n",inode->i_ino);
  
  	block = inode->i_ino;
  	bh = affs_bread(sb, block);
  	if (!bh) {
  		affs_warning(sb, "read_inode", "Cannot read block %d", block);
  		goto bad_inode;
  	}
  	if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
  		affs_warning(sb,"read_inode",
  			   "Checksum or type (ptype=%d) error on inode %d",
  			   AFFS_HEAD(bh)->ptype, block);
  		goto bad_inode;
  	}
  
  	head = AFFS_HEAD(bh);
  	tail = AFFS_TAIL(sb, bh);
  	prot = be32_to_cpu(tail->protect);
  
  	inode->i_size = 0;
  	inode->i_nlink = 1;
  	inode->i_mode = 0;
  	AFFS_I(inode)->i_extcnt = 1;
  	AFFS_I(inode)->i_ext_last = ~1;
  	AFFS_I(inode)->i_protect = prot;
  	AFFS_I(inode)->i_opencnt = 0;
  	AFFS_I(inode)->i_blkcnt = 0;
  	AFFS_I(inode)->i_lc = NULL;
  	AFFS_I(inode)->i_lc_size = 0;
  	AFFS_I(inode)->i_lc_shift = 0;
  	AFFS_I(inode)->i_lc_mask = 0;
  	AFFS_I(inode)->i_ac = NULL;
  	AFFS_I(inode)->i_ext_bh = NULL;
  	AFFS_I(inode)->mmu_private = 0;
  	AFFS_I(inode)->i_lastalloc = 0;
  	AFFS_I(inode)->i_pa_cnt = 0;
  
  	if (sbi->s_flags & SF_SETMODE)
  		inode->i_mode = sbi->s_mode;
  	else
  		inode->i_mode = prot_to_mode(prot);
  
  	id = be16_to_cpu(tail->uid);
  	if (id == 0 || sbi->s_flags & SF_SETUID)
  		inode->i_uid = sbi->s_uid;
  	else if (id == 0xFFFF && sbi->s_flags & SF_MUFS)
  		inode->i_uid = 0;
  	else
  		inode->i_uid = id;
  
  	id = be16_to_cpu(tail->gid);
  	if (id == 0 || sbi->s_flags & SF_SETGID)
  		inode->i_gid = sbi->s_gid;
  	else if (id == 0xFFFF && sbi->s_flags & SF_MUFS)
  		inode->i_gid = 0;
  	else
  		inode->i_gid = id;
  
  	switch (be32_to_cpu(tail->stype)) {
  	case ST_ROOT:
  		inode->i_uid = sbi->s_uid;
  		inode->i_gid = sbi->s_gid;
  		/* fall through */
  	case ST_USERDIR:
  		if (be32_to_cpu(tail->stype) == ST_USERDIR ||
  		    sbi->s_flags & SF_SETMODE) {
  			if (inode->i_mode & S_IRUSR)
  				inode->i_mode |= S_IXUSR;
  			if (inode->i_mode & S_IRGRP)
  				inode->i_mode |= S_IXGRP;
  			if (inode->i_mode & S_IROTH)
  				inode->i_mode |= S_IXOTH;
  			inode->i_mode |= S_IFDIR;
  		} else
  			inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
  		if (tail->link_chain)
  			inode->i_nlink = 2;
  		/* Maybe it should be controlled by mount parameter? */
  		//inode->i_mode |= S_ISVTX;
  		inode->i_op = &affs_dir_inode_operations;
  		inode->i_fop = &affs_dir_operations;
  		break;
  	case ST_LINKDIR:
  #if 0
  		affs_warning(sb, "read_inode", "inode is LINKDIR");
  		goto bad_inode;
  #else
  		inode->i_mode |= S_IFDIR;
  		inode->i_op = NULL;
  		inode->i_fop = NULL;
  		break;
  #endif
  	case ST_LINKFILE:
  		affs_warning(sb, "read_inode", "inode is LINKFILE");
  		goto bad_inode;
  	case ST_FILE:
  		size = be32_to_cpu(tail->size);
  		inode->i_mode |= S_IFREG;
  		AFFS_I(inode)->mmu_private = inode->i_size = size;
  		if (inode->i_size) {
  			AFFS_I(inode)->i_blkcnt = (size - 1) /
  					       sbi->s_data_blksize + 1;
  			AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
  					       sbi->s_hashsize + 1;
  		}
  		if (tail->link_chain)
  			inode->i_nlink = 2;
  		inode->i_mapping->a_ops = (sbi->s_flags & SF_OFS) ? &affs_aops_ofs : &affs_aops;
  		inode->i_op = &affs_file_inode_operations;
  		inode->i_fop = &affs_file_operations;
  		break;
  	case ST_SOFTLINK:
  		inode->i_mode |= S_IFLNK;
  		inode->i_op = &affs_symlink_inode_operations;
  		inode->i_data.a_ops = &affs_symlink_aops;
  		break;
  	}
  
  	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec
  		       = (be32_to_cpu(tail->change.days) * (24 * 60 * 60) +
  		         be32_to_cpu(tail->change.mins) * 60 +
  			 be32_to_cpu(tail->change.ticks) / 50 +
  			 ((8 * 365 + 2) * 24 * 60 * 60)) +
  			 sys_tz.tz_minuteswest * 60;
  	inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = 0;
  	affs_brelse(bh);
  	return;
  
  bad_inode:
  	make_bad_inode(inode);
  	affs_brelse(bh);
  	return;
  }
  
  int
  affs_write_inode(struct inode *inode, int unused)
  {
  	struct super_block	*sb = inode->i_sb;
  	struct buffer_head	*bh;
  	struct affs_tail	*tail;
  	uid_t			 uid;
  	gid_t			 gid;
  
  	pr_debug("AFFS: write_inode(%lu)\n",inode->i_ino);
  
  	if (!inode->i_nlink)
  		// possibly free block
  		return 0;
  	bh = affs_bread(sb, inode->i_ino);
  	if (!bh) {
  		affs_error(sb,"write_inode","Cannot read block %lu",inode->i_ino);
  		return -EIO;
  	}
  	tail = AFFS_TAIL(sb, bh);
  	if (tail->stype == cpu_to_be32(ST_ROOT)) {
  		secs_to_datestamp(inode->i_mtime.tv_sec,&AFFS_ROOT_TAIL(sb, bh)->root_change);
  	} else {
  		tail->protect = cpu_to_be32(AFFS_I(inode)->i_protect);
  		tail->size = cpu_to_be32(inode->i_size);
  		secs_to_datestamp(inode->i_mtime.tv_sec,&tail->change);
  		if (!(inode->i_ino == AFFS_SB(sb)->s_root_block)) {
  			uid = inode->i_uid;
  			gid = inode->i_gid;
  			if (AFFS_SB(sb)->s_flags & SF_MUFS) {
  				if (inode->i_uid == 0 || inode->i_uid == 0xFFFF)
  					uid = inode->i_uid ^ ~0;
  				if (inode->i_gid == 0 || inode->i_gid == 0xFFFF)
  					gid = inode->i_gid ^ ~0;
  			}
  			if (!(AFFS_SB(sb)->s_flags & SF_SETUID))
  				tail->uid = cpu_to_be16(uid);
  			if (!(AFFS_SB(sb)->s_flags & SF_SETGID))
  				tail->gid = cpu_to_be16(gid);
  		}
  	}
  	affs_fix_checksum(sb, bh);
  	mark_buffer_dirty_inode(bh, inode);
  	affs_brelse(bh);
  	affs_free_prealloc(inode);
  	return 0;
  }
  
  int
  affs_notify_change(struct dentry *dentry, struct iattr *attr)
  {
  	struct inode *inode = dentry->d_inode;
  	int error;
  
  	pr_debug("AFFS: notify_change(%lu,0x%x)\n",inode->i_ino,attr->ia_valid);
  
  	error = inode_change_ok(inode,attr);
  	if (error)
  		goto out;
  
  	if (((attr->ia_valid & ATTR_UID) && (AFFS_SB(inode->i_sb)->s_flags & SF_SETUID)) ||
  	    ((attr->ia_valid & ATTR_GID) && (AFFS_SB(inode->i_sb)->s_flags & SF_SETGID)) ||
  	    ((attr->ia_valid & ATTR_MODE) &&
  	     (AFFS_SB(inode->i_sb)->s_flags & (SF_SETMODE | SF_IMMUTABLE)))) {
  		if (!(AFFS_SB(inode->i_sb)->s_flags & SF_QUIET))
  			error = -EPERM;
  		goto out;
  	}
  
  	error = inode_setattr(inode, attr);
  	if (!error && (attr->ia_valid & ATTR_MODE))
  		mode_to_prot(inode);
  out:
  	return error;
  }
  
  void
  affs_put_inode(struct inode *inode)
  {
  	pr_debug("AFFS: put_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
  	affs_free_prealloc(inode);
  	if (atomic_read(&inode->i_count) == 1) {
  		mutex_lock(&inode->i_mutex);
  		if (inode->i_size != AFFS_I(inode)->mmu_private)
  			affs_truncate(inode);
  		mutex_unlock(&inode->i_mutex);
  	}
  }
  
  void
  affs_delete_inode(struct inode *inode)
  {
  	pr_debug("AFFS: delete_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
  	truncate_inode_pages(&inode->i_data, 0);
  	inode->i_size = 0;
  	if (S_ISREG(inode->i_mode))
  		affs_truncate(inode);
  	clear_inode(inode);
  	affs_free_block(inode->i_sb, inode->i_ino);
  }
  
  void
  affs_clear_inode(struct inode *inode)
  {
  	unsigned long cache_page = (unsigned long) AFFS_I(inode)->i_lc;
  
  	pr_debug("AFFS: clear_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
  	if (cache_page) {
  		pr_debug("AFFS: freeing ext cache\n");
  		AFFS_I(inode)->i_lc = NULL;
  		AFFS_I(inode)->i_ac = NULL;
  		free_page(cache_page);
  	}
  	affs_brelse(AFFS_I(inode)->i_ext_bh);
  	AFFS_I(inode)->i_ext_last = ~1;
  	AFFS_I(inode)->i_ext_bh = NULL;
  }
  
  struct inode *
  affs_new_inode(struct inode *dir)
  {
  	struct super_block	*sb = dir->i_sb;
  	struct inode		*inode;
  	u32			 block;
  	struct buffer_head	*bh;
  
  	if (!(inode = new_inode(sb)))
  		goto err_inode;
  
  	if (!(block = affs_alloc_block(dir, dir->i_ino)))
  		goto err_block;
  
  	bh = affs_getzeroblk(sb, block);
  	if (!bh)
  		goto err_bh;
  	mark_buffer_dirty_inode(bh, inode);
  	affs_brelse(bh);
  
  	inode->i_uid     = current->fsuid;
  	inode->i_gid     = current->fsgid;
  	inode->i_ino     = block;
  	inode->i_nlink   = 1;
  	inode->i_mtime   = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
  	AFFS_I(inode)->i_opencnt = 0;
  	AFFS_I(inode)->i_blkcnt = 0;
  	AFFS_I(inode)->i_lc = NULL;
  	AFFS_I(inode)->i_lc_size = 0;
  	AFFS_I(inode)->i_lc_shift = 0;
  	AFFS_I(inode)->i_lc_mask = 0;
  	AFFS_I(inode)->i_ac = NULL;
  	AFFS_I(inode)->i_ext_bh = NULL;
  	AFFS_I(inode)->mmu_private = 0;
  	AFFS_I(inode)->i_protect = 0;
  	AFFS_I(inode)->i_lastalloc = 0;
  	AFFS_I(inode)->i_pa_cnt = 0;
  	AFFS_I(inode)->i_extcnt = 1;
  	AFFS_I(inode)->i_ext_last = ~1;
  
  	insert_inode_hash(inode);
  
  	return inode;
  
  err_bh:
  	affs_free_block(sb, block);
  err_block:
  	iput(inode);
  err_inode:
  	return NULL;
  }
  
  /*
   * Add an entry to a directory. Create the header block
   * and insert it into the hash table.
   */
  
  int
  affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
  {
  	struct super_block *sb = dir->i_sb;
  	struct buffer_head *inode_bh = NULL;
  	struct buffer_head *bh = NULL;
  	u32 block = 0;
  	int retval;
  
  	pr_debug("AFFS: add_entry(dir=%u, inode=%u, \"%*s\", type=%d)\n", (u32)dir->i_ino,
  	         (u32)inode->i_ino, (int)dentry->d_name.len, dentry->d_name.name, type);
  
  	retval = -EIO;
  	bh = affs_bread(sb, inode->i_ino);
  	if (!bh)
  		goto done;
  
  	affs_lock_link(inode);
  	switch (type) {
  	case ST_LINKFILE:
  	case ST_LINKDIR:
  		inode_bh = bh;
  		retval = -ENOSPC;
  		block = affs_alloc_block(dir, dir->i_ino);
  		if (!block)
  			goto err;
  		retval = -EIO;
  		bh = affs_getzeroblk(sb, block);
  		if (!bh)
  			goto err;
  		break;
  	default:
  		break;
  	}
  
  	AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
  	AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
  	affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
  	AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
  	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
  
  	if (inode_bh) {
  		__be32 chain;
  	       	chain = AFFS_TAIL(sb, inode_bh)->link_chain;
  		AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
  		AFFS_TAIL(sb, bh)->link_chain = chain;
  		AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
  		affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
  		mark_buffer_dirty_inode(inode_bh, inode);
  		inode->i_nlink = 2;
  		atomic_inc(&inode->i_count);
  	}
  	affs_fix_checksum(sb, bh);
  	mark_buffer_dirty_inode(bh, inode);
  	dentry->d_fsdata = (void *)(long)bh->b_blocknr;
  
  	affs_lock_dir(dir);
  	retval = affs_insert_hash(dir, bh);
  	mark_buffer_dirty_inode(bh, inode);
  	affs_unlock_dir(dir);
  	affs_unlock_link(inode);
  
  	d_instantiate(dentry, inode);
  done:
  	affs_brelse(inode_bh);
  	affs_brelse(bh);
  	return retval;
  err:
  	if (block)
  		affs_free_block(sb, block);
  	affs_unlock_link(inode);
  	goto done;
  }
  