C++ NILFS_I函数代码示例

int nilfs_set_file_dirty(struct inode *inode, unsigned nr_dirty)
{
	struct nilfs_inode_info *ii = NILFS_I(inode);
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;

	atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);

	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
		return 0;

	spin_lock(&nilfs->ns_inode_lock);
	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
			nilfs_warning(inode->i_sb, __func__,
				      "cannot get inode (ino=%lu)\n",
				      inode->i_ino);
			spin_unlock(&nilfs->ns_inode_lock);
			return -EINVAL; 
		}
		list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
		set_bit(NILFS_I_QUEUED, &ii->i_state);
	}
	spin_unlock(&nilfs->ns_inode_lock);
	return 0;
}

void nilfs_evict_inode(struct inode *inode)
{
	struct nilfs_transaction_info ti;
	struct super_block *sb = inode->i_sb;
	struct nilfs_inode_info *ii = NILFS_I(inode);
	int ret;

	if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
		if (inode->i_data.nrpages)
			truncate_inode_pages(&inode->i_data, 0);
		end_writeback(inode);
		nilfs_clear_inode(inode);
		return;
	}
	nilfs_transaction_begin(sb, &ti, 0); 

	if (inode->i_data.nrpages)
		truncate_inode_pages(&inode->i_data, 0);

	
	nilfs_truncate_bmap(ii, 0);
	nilfs_mark_inode_dirty(inode);
	end_writeback(inode);

	ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
	if (!ret)
		atomic_dec(&ii->i_root->inodes_count);

	nilfs_clear_inode(inode);

	if (IS_SYNC(inode))
		nilfs_set_transaction_flag(NILFS_TI_SYNC);
	nilfs_transaction_commit(sb);
}

/**
 * nilfs_mdt_find_block - find and get a buffer on meta data file.
 * @inode: inode of the meta data file
 * @start: start block offset (inclusive)
 * @end: end block offset (inclusive)
 * @blkoff: block offset
 * @out_bh: place to store a pointer to buffer_head struct
 *
 * nilfs_mdt_find_block() looks up an existing block in range of
 * [@start, @end] and stores pointer to a buffer head of the block to
 * @out_bh, and block offset to @blkoff, respectively.  @out_bh and
 * @blkoff are substituted only when zero is returned.
 *
 * Return Value: On success, it returns 0. On error, the following negative
 * error code is returned.
 *
 * %-ENOMEM - Insufficient memory available.
 *
 * %-EIO - I/O error
 *
 * %-ENOENT - no block was found in the range
 */
int nilfs_mdt_find_block(struct inode *inode, unsigned long start,
			 unsigned long end, unsigned long *blkoff,
			 struct buffer_head **out_bh)
{
	__u64 next;
	int ret;

	if (unlikely(start > end))
		return -ENOENT;

	ret = nilfs_mdt_read_block(inode, start, true, out_bh);
	if (!ret) {
		*blkoff = start;
		goto out;
	}
	if (unlikely(ret != -ENOENT || start == ULONG_MAX))
		goto out;

	ret = nilfs_bmap_seek_key(NILFS_I(inode)->i_bmap, start + 1, &next);
	if (!ret) {
		if (next <= end) {
			ret = nilfs_mdt_read_block(inode, next, true, out_bh);
			if (!ret)
				*blkoff = next;
		} else {
			ret = -ENOENT;
		}
	}
out:
	return ret;
}

static int nilfs_iget_set(struct inode *inode, void *opaque)
{
	struct nilfs_iget_args *args = opaque;

	inode->i_ino = args->ino;
	if (args->for_gc) {
		NILFS_I(inode)->i_state = 1 << NILFS_I_GCINODE;
		NILFS_I(inode)->i_cno = args->cno;
		NILFS_I(inode)->i_root = NULL;
	} else {
		if (args->root && args->ino == NILFS_ROOT_INO)
			nilfs_get_root(args->root);
		NILFS_I(inode)->i_root = args->root;
	}
	return 0;
}

static void nilfs_clear_inode(struct inode *inode)
{
	struct nilfs_inode_info *ii = NILFS_I(inode);

#ifdef CONFIG_NILFS_POSIX_ACL
	if (ii->i_acl && ii->i_acl != NILFS_ACL_NOT_CACHED) {
		posix_acl_release(ii->i_acl);
		ii->i_acl = NILFS_ACL_NOT_CACHED;
	}
	if (ii->i_default_acl && ii->i_default_acl != NILFS_ACL_NOT_CACHED) {
		posix_acl_release(ii->i_default_acl);
		ii->i_default_acl = NILFS_ACL_NOT_CACHED;
	}
#endif
	/*
	 * Free resources allocated in nilfs_read_inode(), here.
	 */
	BUG_ON(!list_empty(&ii->i_dirty));
	brelse(ii->i_bh);
	ii->i_bh = NULL;

	if (test_bit(NILFS_I_BMAP, &ii->i_state))
		nilfs_bmap_clear(ii->i_bmap);

	nilfs_btnode_cache_clear(&ii->i_btnode_cache);
}

static int nilfs_encode_fh(struct inode *inode, __u32 *fh, int *lenp,
			   struct inode *parent)
{
	struct nilfs_fid *fid = (struct nilfs_fid *)fh;
	struct nilfs_root *root = NILFS_I(inode)->i_root;
	int type;

	if (parent && *lenp < NILFS_FID_SIZE_CONNECTABLE) {
		*lenp = NILFS_FID_SIZE_CONNECTABLE;
		return FILEID_INVALID;
	}
	if (*lenp < NILFS_FID_SIZE_NON_CONNECTABLE) {
		*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
		return FILEID_INVALID;
	}

	fid->cno = root->cno;
	fid->ino = inode->i_ino;
	fid->gen = inode->i_generation;

	if (parent) {
		fid->parent_ino = parent->i_ino;
		fid->parent_gen = parent->i_generation;
		type = FILEID_NILFS_WITH_PARENT;
		*lenp = NILFS_FID_SIZE_CONNECTABLE;
	} else {
		type = FILEID_NILFS_WITHOUT_PARENT;
		*lenp = NILFS_FID_SIZE_NON_CONNECTABLE;
	}

	return type;
}

int nilfs_set_file_dirty(struct inode *inode, unsigned nr_dirty)
{
	struct nilfs_inode_info *ii = NILFS_I(inode);
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;

	atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);

	if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
		return 0;

	spin_lock(&nilfs->ns_inode_lock);
	if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
	    !test_bit(NILFS_I_BUSY, &ii->i_state)) {
		/* Because this routine may race with nilfs_dispose_list(),
		   we have to check NILFS_I_QUEUED here, too. */
		if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
			/* This will happen when somebody is freeing
			   this inode. */
			nilfs_warning(inode->i_sb, __func__,
				      "cannot get inode (ino=%lu)\n",
				      inode->i_ino);
			spin_unlock(&nilfs->ns_inode_lock);
			return -EINVAL; /* NILFS_I_DIRTY may remain for
					   freeing inode */
		}
		list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
		set_bit(NILFS_I_QUEUED, &ii->i_state);
	}
	spin_unlock(&nilfs->ns_inode_lock);
	return 0;
}

void nilfs_evict_inode(struct inode *inode)
{
	struct nilfs_transaction_info ti;
	struct super_block *sb = inode->i_sb;
	struct nilfs_inode_info *ii = NILFS_I(inode);
	int ret;

	if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
		truncate_inode_pages_final(&inode->i_data);
		clear_inode(inode);
		nilfs_clear_inode(inode);
		return;
	}
	nilfs_transaction_begin(sb, &ti, 0); /* never fails */

	truncate_inode_pages_final(&inode->i_data);

	/* TODO: some of the following operations may fail.  */
	nilfs_truncate_bmap(ii, 0);
	nilfs_mark_inode_dirty(inode);
	clear_inode(inode);

	ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
	if (!ret)
		atomic64_dec(&ii->i_root->inodes_count);

	nilfs_clear_inode(inode);

	if (IS_SYNC(inode))
		nilfs_set_transaction_flag(NILFS_TI_SYNC);
	nilfs_transaction_commit(sb);
	/* May construct a logical segment and may fail in sync mode.
	   But delete_inode has no return value. */
}

int nilfs_load_inode_block(struct nilfs_sb_info *sbi, struct inode *inode,
			   struct buffer_head **pbh)
{
	struct nilfs_inode_info *ii = NILFS_I(inode);
	int err;

	spin_lock(&sbi->s_inode_lock);
	/* Caller of this function MUST lock s_inode_lock */
	if (ii->i_bh == NULL) {
		spin_unlock(&sbi->s_inode_lock);
		err = nilfs_ifile_get_inode_block(sbi->s_ifile, inode->i_ino,
						  pbh);
		if (unlikely(err))
			return err;
		spin_lock(&sbi->s_inode_lock);
		if (ii->i_bh == NULL)
			ii->i_bh = *pbh;
		else {
			brelse(*pbh);
			*pbh = ii->i_bh;
		}
	} else
		*pbh = ii->i_bh;

	get_bh(*pbh);
	spin_unlock(&sbi->s_inode_lock);
	return 0;
}

int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
{
	struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
	struct nilfs_inode_info *ii = NILFS_I(inode);
	int err;

	spin_lock(&nilfs->ns_inode_lock);
	if (ii->i_bh == NULL) {
		spin_unlock(&nilfs->ns_inode_lock);
		err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
						  inode->i_ino, pbh);
		if (unlikely(err))
			return err;
		spin_lock(&nilfs->ns_inode_lock);
		if (ii->i_bh == NULL)
			ii->i_bh = *pbh;
		else {
			brelse(*pbh);
			*pbh = ii->i_bh;
		}
	} else
		*pbh = ii->i_bh;

	get_bh(*pbh);
	spin_unlock(&nilfs->ns_inode_lock);
	return 0;
}

void nilfs_delete_inode(struct inode *inode)
{
	struct nilfs_transaction_info ti;
	struct super_block *sb = inode->i_sb;
	struct nilfs_inode_info *ii = NILFS_I(inode);

	if (unlikely(is_bad_inode(inode))) {
		if (inode->i_data.nrpages)
			truncate_inode_pages(&inode->i_data, 0);
		clear_inode(inode);
		return;
	}
	nilfs_transaction_begin(sb, &ti, 0); /* never fails */

	if (inode->i_data.nrpages)
		truncate_inode_pages(&inode->i_data, 0);

	nilfs_truncate_bmap(ii, 0);
	nilfs_free_inode(inode);
	/* nilfs_free_inode() marks inode buffer dirty */
	if (IS_SYNC(inode))
		nilfs_set_transaction_flag(NILFS_TI_SYNC);
	nilfs_transaction_commit(sb);
	/* May construct a logical segment and may fail in sync mode.
	   But delete_inode has no return value. */
}

void nilfs_truncate(struct inode *inode)
{
	unsigned long blkoff;
	unsigned int blocksize;
	struct nilfs_transaction_info ti;
	struct super_block *sb = inode->i_sb;
	struct nilfs_inode_info *ii = NILFS_I(inode);

	if (!test_bit(NILFS_I_BMAP, &ii->i_state))
		return;
	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
		return;

	blocksize = sb->s_blocksize;
	blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
	nilfs_transaction_begin(sb, &ti, 0); /* never fails */

	block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);

	nilfs_truncate_bmap(ii, blkoff);

	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	if (IS_SYNC(inode))
		nilfs_set_transaction_flag(NILFS_TI_SYNC);

	nilfs_set_file_dirty(NILFS_SB(sb), inode, 0);
	nilfs_transaction_commit(sb);
	/* May construct a logical segment and may fail in sync mode.
	   But truncate has no return value. */
}

void nilfs_write_inode_common(struct inode *inode,
			      struct nilfs_inode *raw_inode, int has_bmap)
{
	struct nilfs_inode_info *ii = NILFS_I(inode);

	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
	raw_inode->i_uid = cpu_to_le32(inode->i_uid);
	raw_inode->i_gid = cpu_to_le32(inode->i_gid);
	raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
	raw_inode->i_size = cpu_to_le64(inode->i_size);
	raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
	raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
	raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
	raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
	raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);

	raw_inode->i_flags = cpu_to_le32(ii->i_flags);
	raw_inode->i_generation = cpu_to_le32(inode->i_generation);

	if (has_bmap)
		nilfs_bmap_write(ii->i_bmap, raw_inode);
	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
		raw_inode->i_device_code =
			cpu_to_le64(new_encode_dev(inode->i_rdev));
	/* When extending inode, nilfs->ns_inode_size should be checked
	   for substitutions of appended fields */
}

static int
nilfs_mdt_insert_new_block(struct inode *inode, unsigned long block,
			   struct buffer_head *bh,
			   void (*init_block)(struct inode *,
					      struct buffer_head *, void *))
{
	struct nilfs_inode_info *ii = NILFS_I(inode);
	void *kaddr;
	int ret;

	/* Caller exclude read accesses using page lock */

	/* set_buffer_new(bh); */
	bh->b_blocknr = 0;

	ret = nilfs_bmap_insert(ii->i_bmap, block, (unsigned long)bh);
	if (unlikely(ret))
		return ret;

	set_buffer_mapped(bh);

	kaddr = kmap_atomic(bh->b_page, KM_USER0);
	memset(kaddr + bh_offset(bh), 0, 1 << inode->i_blkbits);
	if (init_block)
		init_block(inode, bh, kaddr);
	flush_dcache_page(bh->b_page);
	kunmap_atomic(kaddr, KM_USER0);

	set_buffer_uptodate(bh);
	nilfs_mark_buffer_dirty(bh);
	nilfs_mdt_mark_dirty(inode);
	return 0;
}

void nilfs_inode_add_blocks(struct inode *inode, int n)
{
	struct nilfs_root *root = NILFS_I(inode)->i_root;

	inode_add_bytes(inode, i_blocksize(inode) * n);
	if (root)
		atomic64_add(n, &root->blocks_count);
}