Пример #1
0
/*
** reiserfs_unpack
** Function try to convert tail from direct item into indirect.
** It set up nopack attribute in the REISERFS_I(inode)->nopack
*/
int reiserfs_unpack(struct inode *inode, struct file *filp)
{
	int retval = 0;
	int depth;
	int index;
	struct page *page;
	struct address_space *mapping;
	unsigned long write_from;
	unsigned long blocksize = inode->i_sb->s_blocksize;

	if (inode->i_size == 0) {
		REISERFS_I(inode)->i_flags |= i_nopack_mask;
		return 0;
	}
	/* ioctl already done */
	if (REISERFS_I(inode)->i_flags & i_nopack_mask) {
		return 0;
	}

	depth = reiserfs_write_lock_once(inode->i_sb);

	/* we need to make sure nobody is changing the file size beneath us */
	reiserfs_mutex_lock_safe(&inode->i_mutex, inode->i_sb);

	write_from = inode->i_size & (blocksize - 1);
	/* if we are on a block boundary, we are already unpacked.  */
	if (write_from == 0) {
		REISERFS_I(inode)->i_flags |= i_nopack_mask;
		goto out;
	}

	/* we unpack by finding the page with the tail, and calling
	 ** __reiserfs_write_begin on that page.  This will force a
	 ** reiserfs_get_block to unpack the tail for us.
	 */
	index = inode->i_size >> PAGE_CACHE_SHIFT;
	mapping = inode->i_mapping;
	page = grab_cache_page(mapping, index);
	retval = -ENOMEM;
	if (!page) {
		goto out;
	}
	retval = __reiserfs_write_begin(page, write_from, 0);
	if (retval)
		goto out_unlock;

	/* conversion can change page contents, must flush */
	flush_dcache_page(page);
	retval = reiserfs_commit_write(NULL, page, write_from, write_from);
	REISERFS_I(inode)->i_flags |= i_nopack_mask;

      out_unlock:
	unlock_page(page);
	page_cache_release(page);

      out:
	mutex_unlock(&inode->i_mutex);
	reiserfs_write_unlock_once(inode->i_sb, depth);
	return retval;
}
Пример #2
0
/*
 * inode->i_mutex: down
 */
int
reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
			  struct inode *inode, const char *name,
			  const void *buffer, size_t buffer_size, int flags)
{
	int err = 0;
	struct dentry *dentry;
	struct page *page;
	char *data;
	size_t file_pos = 0;
	size_t buffer_pos = 0;
	size_t new_size;
	__u32 xahash = 0;

	if (get_inode_sd_version(inode) == STAT_DATA_V1)
		return -EOPNOTSUPP;

	reiserfs_write_unlock(inode->i_sb);

	if (!buffer) {
		err = lookup_and_delete_xattr(inode, name);
		reiserfs_write_lock(inode->i_sb);
		return err;
	}

	dentry = xattr_lookup(inode, name, flags);
	if (IS_ERR(dentry)) {
		reiserfs_write_lock(inode->i_sb);
		return PTR_ERR(dentry);
	}

	down_write(&REISERFS_I(inode)->i_xattr_sem);

	reiserfs_write_lock(inode->i_sb);

	xahash = xattr_hash(buffer, buffer_size);
	while (buffer_pos < buffer_size || buffer_pos == 0) {
		size_t chunk;
		size_t skip = 0;
		size_t page_offset = (file_pos & (PAGE_CACHE_SIZE - 1));
		if (buffer_size - buffer_pos > PAGE_CACHE_SIZE)
			chunk = PAGE_CACHE_SIZE;
		else
			chunk = buffer_size - buffer_pos;

		page = reiserfs_get_page(dentry->d_inode, file_pos);
		if (IS_ERR(page)) {
			err = PTR_ERR(page);
			goto out_unlock;
		}

		lock_page(page);
		data = page_address(page);

		if (file_pos == 0) {
			struct reiserfs_xattr_header *rxh;
			skip = file_pos = sizeof(struct reiserfs_xattr_header);
			if (chunk + skip > PAGE_CACHE_SIZE)
				chunk = PAGE_CACHE_SIZE - skip;
			rxh = (struct reiserfs_xattr_header *)data;
			rxh->h_magic = cpu_to_le32(REISERFS_XATTR_MAGIC);
			rxh->h_hash = cpu_to_le32(xahash);
		}

		err = __reiserfs_write_begin(page, page_offset, chunk + skip);
		if (!err) {
			if (buffer)
				memcpy(data + skip, buffer + buffer_pos, chunk);
			err = reiserfs_commit_write(NULL, page, page_offset,
						    page_offset + chunk +
						    skip);
		}
		unlock_page(page);
		reiserfs_put_page(page);
		buffer_pos += chunk;
		file_pos += chunk;
		skip = 0;
		if (err || buffer_size == 0 || !buffer)
			break;
	}

	new_size = buffer_size + sizeof(struct reiserfs_xattr_header);
	if (!err && new_size < i_size_read(dentry->d_inode)) {
		struct iattr newattrs = {
			.ia_ctime = current_fs_time(inode->i_sb),
			.ia_size = new_size,
			.ia_valid = ATTR_SIZE | ATTR_CTIME,
		};

		reiserfs_write_unlock(inode->i_sb);
		mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
		down_write(&dentry->d_inode->i_alloc_sem);
		reiserfs_write_lock(inode->i_sb);

		err = reiserfs_setattr(dentry, &newattrs);
		up_write(&dentry->d_inode->i_alloc_sem);
		mutex_unlock(&dentry->d_inode->i_mutex);
	} else
		update_ctime(inode);
out_unlock:
	up_write(&REISERFS_I(inode)->i_xattr_sem);
	dput(dentry);
	return err;
}