namei.c

ocfs1.4.1 oracle分布式文件系统

	 * anyway. */
	if ((p_blocks << sb->s_blocksize_bits) < bytes_left) {
		status = -EIO;
		mlog_errno(status);
		goto bail;
	}

	virtual = 0;
	while(bytes_left > 0) {
		c = &symname[virtual * sb->s_blocksize];

		bhs[virtual] = sb_getblk(sb, p_blkno);
		if (!bhs[virtual]) {
			status = -ENOMEM;
			mlog_errno(status);
			goto bail;
		}
		ocfs2_set_new_buffer_uptodate(inode, bhs[virtual]);

		status = ocfs2_journal_access(handle, inode, bhs[virtual],
					      OCFS2_JOURNAL_ACCESS_CREATE);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}

		memset(bhs[virtual]->b_data, 0, sb->s_blocksize);

		memcpy(bhs[virtual]->b_data, c,
		       (bytes_left > sb->s_blocksize) ? sb->s_blocksize :
		       bytes_left);

		status = ocfs2_journal_dirty(handle, bhs[virtual]);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}

		virtual++;
		p_blkno++;
		bytes_left -= sb->s_blocksize;
	}

	status = 0;
bail:

	if (bhs) {
		for(i = 0; i < blocks; i++)
			if (bhs[i])
				brelse(bhs[i]);
		kfree(bhs);
	}

	mlog_exit(status);
	return status;
}

static int ocfs2_symlink(struct inode *dir,
			 struct dentry *dentry,
			 const char *symname)
{
	int status, l, credits;
	u64 newsize;
	struct ocfs2_super *osb = NULL;
	struct inode *inode = NULL;
	struct super_block *sb;
	struct buffer_head *new_fe_bh = NULL;
	struct buffer_head *de_bh = NULL;
	struct buffer_head *parent_fe_bh = NULL;
	struct ocfs2_dinode *fe = NULL;
	struct ocfs2_dinode *dirfe;
	handle_t *handle = NULL;
	struct ocfs2_alloc_context *inode_ac = NULL;
	struct ocfs2_alloc_context *data_ac = NULL;

	mlog_entry("(0x%p, 0x%p, symname='%s' actual='%.*s')\n", dir,
		   dentry, symname, dentry->d_name.len, dentry->d_name.name);

	sb = dir->i_sb;
	osb = OCFS2_SB(sb);

	l = strlen(symname) + 1;

	credits = ocfs2_calc_symlink_credits(sb);

	/* lock the parent directory */
	status = ocfs2_inode_lock(dir, &parent_fe_bh, 1);
	if (status < 0) {
		if (status != -ENOENT)
			mlog_errno(status);
		return status;
	}

	dirfe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
	if (!dirfe->i_links_count) {
		/* can't make a file in a deleted directory. */
		status = -ENOENT;
		goto bail;
	}

	status = ocfs2_check_dir_for_entry(dir, dentry->d_name.name,
					   dentry->d_name.len);
	if (status)
		goto bail;

	status = ocfs2_prepare_dir_for_insert(osb, dir, parent_fe_bh,
					      dentry->d_name.name,
					      dentry->d_name.len, &de_bh);
	if (status < 0) {
		mlog_errno(status);
		goto bail;
	}

	status = ocfs2_reserve_new_inode(osb, &inode_ac);
	if (status < 0) {
		if (status != -ENOSPC)
			mlog_errno(status);
		goto bail;
	}

	/* don't reserve bitmap space for fast symlinks. */
	if (l > ocfs2_fast_symlink_chars(sb)) {
		status = ocfs2_reserve_clusters(osb, 1, &data_ac);
		if (status < 0) {
			if (status != -ENOSPC)
				mlog_errno(status);
			goto bail;
		}
	}

	handle = ocfs2_start_trans(osb, credits);
	if (IS_ERR(handle)) {
		status = PTR_ERR(handle);
		handle = NULL;
		mlog_errno(status);
		goto bail;
	}

	status = ocfs2_mknod_locked(osb, dir, dentry,
				    S_IFLNK | S_IRWXUGO, 0,
				    &new_fe_bh, parent_fe_bh, handle,
				    &inode, inode_ac);
	if (status < 0) {
		mlog_errno(status);
		goto bail;
	}

	fe = (struct ocfs2_dinode *) new_fe_bh->b_data;
	inode->i_rdev = 0;
	newsize = l - 1;
	if (l > ocfs2_fast_symlink_chars(sb)) {
		u32 offset = 0;

		inode->i_op = &ocfs2_symlink_inode_operations;
		status = ocfs2_do_extend_allocation(osb, inode, &offset, 1, 0,
						    new_fe_bh,
						    handle, data_ac, NULL,
						    NULL);
		if (status < 0) {
			if (status != -ENOSPC && status != -EINTR) {
				mlog(ML_ERROR,
				     "Failed to extend file to %llu\n",
				     (unsigned long long)newsize);
				mlog_errno(status);
				status = -ENOSPC;
			}
			goto bail;
		}
		i_size_write(inode, newsize);
		inode->i_blocks = ocfs2_inode_sector_count(inode);
	} else {
		inode->i_op = &ocfs2_fast_symlink_inode_operations;
		memcpy((char *) fe->id2.i_symlink, symname, l);
		i_size_write(inode, newsize);
		inode->i_blocks = 0;
	}

	status = ocfs2_mark_inode_dirty(handle, inode, new_fe_bh);
	if (status < 0) {
		mlog_errno(status);
		goto bail;
	}

	if (!ocfs2_inode_is_fast_symlink(inode)) {
		status = ocfs2_create_symlink_data(osb, handle, inode,
						   symname);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}
	}

	status = ocfs2_add_entry(handle, dentry, inode,
				 le64_to_cpu(fe->i_blkno), parent_fe_bh,
				 de_bh);
	if (status < 0) {
		mlog_errno(status);
		goto bail;
	}

	status = ocfs2_dentry_attach_lock(dentry, inode, OCFS2_I(dir)->ip_blkno);
	if (status) {
		mlog_errno(status);
		goto bail;
	}

	insert_inode_hash(inode);
	dentry->d_op = &ocfs2_dentry_ops;
	d_instantiate(dentry, inode);
bail:
	if (handle)
		ocfs2_commit_trans(osb, handle);

	ocfs2_inode_unlock(dir, 1);

	if (new_fe_bh)
		brelse(new_fe_bh);
	if (parent_fe_bh)
		brelse(parent_fe_bh);
	if (de_bh)
		brelse(de_bh);
	if (inode_ac)
		ocfs2_free_alloc_context(inode_ac);
	if (data_ac)
		ocfs2_free_alloc_context(data_ac);
	if ((status < 0) && inode)
		iput(inode);

	mlog_exit(status);

	return status;
}

static int ocfs2_blkno_stringify(u64 blkno, char *name)
{
	int status, namelen;

	mlog_entry_void();

	namelen = snprintf(name, OCFS2_ORPHAN_NAMELEN + 1, "%016llx",
			   (long long)blkno);
	if (namelen <= 0) {
		if (namelen)
			status = namelen;
		else
			status = -EINVAL;
		mlog_errno(status);
		goto bail;
	}
	if (namelen != OCFS2_ORPHAN_NAMELEN) {
		status = -EINVAL;
		mlog_errno(status);
		goto bail;
	}

	mlog(0, "built filename '%s' for orphan dir (len=%d)\n", name,
	     namelen);

	status = 0;
bail:
	mlog_exit(status);
	return status;
}

static int ocfs2_prepare_orphan_dir(struct ocfs2_super *osb,
				    struct inode **ret_orphan_dir,
				    struct inode *inode,
				    char *name,
				    struct buffer_head **de_bh)
{
	struct inode *orphan_dir_inode;
	struct buffer_head *orphan_dir_bh = NULL;
	int status = 0;

	status = ocfs2_blkno_stringify(OCFS2_I(inode)->ip_blkno, name);
	if (status < 0) {
		mlog_errno(status);
		return status;
	}

	orphan_dir_inode = ocfs2_get_system_file_inode(osb,
						       ORPHAN_DIR_SYSTEM_INODE,
						       osb->slot_num);
	if (!orphan_dir_inode) {
		status = -ENOENT;
		mlog_errno(status);
		return status;
	}

	mutex_lock(&orphan_dir_inode->i_mutex);

	status = ocfs2_inode_lock(orphan_dir_inode, &orphan_dir_bh, 1);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	status = ocfs2_prepare_dir_for_insert(osb, orphan_dir_inode,
					      orphan_dir_bh, name,
					      OCFS2_ORPHAN_NAMELEN, de_bh);
	if (status < 0) {
		ocfs2_inode_unlock(orphan_dir_inode, 1);

		mlog_errno(status);
		goto leave;
	}

	*ret_orphan_dir = orphan_dir_inode;

leave:
	if (status) {
		mutex_unlock(&orphan_dir_inode->i_mutex);
		iput(orphan_dir_inode);
	}

	if (orphan_dir_bh)
		brelse(orphan_dir_bh);

	mlog_exit(status);
	return status;
}

static int ocfs2_orphan_add(struct ocfs2_super *osb,
			    handle_t *handle,
			    struct inode *inode,
			    struct ocfs2_dinode *fe,
			    char *name,
			    struct buffer_head *de_bh,
			    struct inode *orphan_dir_inode)
{
	struct buffer_head *orphan_dir_bh = NULL;
	int status = 0;
	struct ocfs2_dinode *orphan_fe;

	mlog_entry("(inode->i_ino = %lu)\n", inode->i_ino);

	status = ocfs2_read_block(osb,
				  OCFS2_I(orphan_dir_inode)->ip_blkno,
				  &orphan_dir_bh, OCFS2_BH_CACHED,
				  orphan_dir_inode);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	status = ocfs2_journal_access(handle, orphan_dir_inode, orphan_dir_bh,
				      OCFS2_JOURNAL_ACCESS_WRITE);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	/* we're a cluster, and nlink can change on disk from
	 * underneath us... */
	orphan_fe = (struct ocfs2_dinode *) orphan_dir_bh->b_data;
	if (S_ISDIR(inode->i_mode))
		le16_add_cpu(&orphan_fe->i_links_count, 1);
	orphan_dir_inode->i_nlink = le16_to_cpu(orphan_fe->i_links_count);

	status = ocfs2_journal_dirty(handle, orphan_dir_bh);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	status = __ocfs2_add_entry(handle, orphan_dir_inode, name,
				   OCFS2_ORPHAN_NAMELEN, inode,
				   OCFS2_I(inode)->ip_blkno,
				   orphan_dir_bh, de_bh);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	le32_add_cpu(&fe->i_flags, OCFS2_ORPHANED_FL);

	/* Record which orphan dir our inode now resides
	 * in. delete_inode will use this to determine which orphan
	 * dir to lock. */
	fe->i_orphaned_slot = cpu_to_le16(osb->slot_num);

	mlog(0, "Inode %llu orphaned in slot %d\n",
	     (unsigned long long)OCFS2_I(inode)->ip_blkno, osb->slot_num);

leave:
	if (orphan_dir_bh)
		brelse(orphan_dir_bh);

	mlog_exit(status);
	return status;
}

/* unlike orphan_add, we expect the orphan dir to already be locked here. */
int ocfs2_orphan_del(struct ocfs2_super *osb,
		     handle_t *handle,
		     struct inode *orphan_dir_inode,
		     struct inode *inode,
		     struct buffer_head *orphan_dir_bh)
{
	char name[OCFS2_ORPHAN_NAMELEN + 1];
	struct ocfs2_dinode *orphan_fe;
	int status = 0;
	struct buffer_head *target_de_bh = NULL;
	struct ocfs2_dir_entry *target_de = NULL;

	mlog_entry_void();

	status = ocfs2_blkno_stringify(OCFS2_I(inode)->ip_blkno, name);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	mlog(0, "removing '%s' from orphan dir %llu (namelen=%d)\n",
	     name, (unsigned long long)OCFS2_I(orphan_dir_inode)->ip_blkno,
	     OCFS2_ORPHAN_NAMELEN);

	/* find it's spot in the orphan directory */
	target_de_bh = ocfs2_find_entry(name, OCFS2_ORPHAN_NAMELEN,
					orphan_dir_inode, &target_de);
	if (!target_de_bh) {
		status = -ENOENT;
		mlog_errno(status);
		goto leave;
	}

	/* remove it from the orphan directory */
	status = ocfs2_delete_entry(handle, orphan_dir_inode, target_de,
				    target_de_bh);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	status = ocfs2_journal_access(handle,orphan_dir_inode,  orphan_dir_bh,
				      OCFS2_JOURNAL_ACCESS_WRITE);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

	/* do the i_nlink dance! :) */
	orphan_fe = (struct ocfs2_dinode *) orphan_dir_bh->b_data;
	if (S_ISDIR(inode->i_mode))
		le16_add_cpu(&orphan_fe->i_links_count, -1);
	orphan_dir_inode->i_nlink = le16_to_cpu(orphan_fe->i_links_count);

	status = ocfs2_journal_dirty(handle, orphan_dir_bh);
	if (status < 0) {
		mlog_errno(status);
		goto leave;
	}

leave:
	if (target_de_bh)
		brelse(target_de_bh);

	mlog_exit(status);
	return status;
}

#ifdef IOP_IS_NOT_CONST
struct inode_operations ocfs2_dir_iops = {
#else
const struct inode_operations ocfs2_dir_iops = {
#endif
	.create		= ocfs2_create,
	.lookup		= ocfs2_lookup,
	.link		= ocfs2_link,
	.unlink		= ocfs2_unlink,
	.rmdir		= ocfs2_unlink,
	.symlink	= ocfs2_symlink,
	.mkdir		= ocfs2_mkdir,
	.mknod		= ocfs2_mknod,
	.rename		= ocfs2_rename,
	.setattr	= ocfs2_setattr,
	.getattr	= ocfs2_getattr,
	.permission	= ocfs2_permission,
};