namei.c

ocfs1.2.7 源码

		goto bail;

	/* check if the target already exists (in which case we need
	 * to delete it */
	status = ocfs2_find_files_on_disk(new_dentry->d_name.name,
					  new_dentry->d_name.len,
					  &newfe_blkno, new_dir, &new_de_bh,
					  &new_de);
	/* The only error we allow here is -ENOENT because the new
	 * file not existing is perfectly valid. */
	if ((status < 0) && (status != -ENOENT)) {
		/* If we cannot find the file specified we should just */
		/* return the error... */
		mlog_errno(status);
		goto bail;
	}

	if (!new_de && new_inode)
		mlog(ML_ERROR, "inode %lu does not exist in it's parent "
		     "directory!", new_inode->i_ino);

	/* In case we need to overwrite an existing file, we blow it
	 * away first */
	if (new_de) {
		/* VFS didn't think there existed an inode here, but
		 * someone else in the cluster must have raced our
		 * rename to create one. Today we error cleanly, in
		 * the future we should consider calling iget to build
		 * a new struct inode for this entry. */
		if (!new_inode) {
			status = -EACCES;

			mlog(0, "We found an inode for name %.*s but VFS "
			     "didn't give us one.\n", new_dentry->d_name.len,
			     new_dentry->d_name.name);
			goto bail;
		}

		if (OCFS2_I(new_inode)->ip_blkno != newfe_blkno) {
			status = -EACCES;

			mlog(0, "Inode blkno (%"MLFu64") and dir (%"MLFu64") "
			     "disagree. ip_flags = %x\n",
			     OCFS2_I(new_inode)->ip_blkno, newfe_blkno,
			     OCFS2_I(new_inode)->ip_flags);
			goto bail;
		}

		status = ocfs2_meta_lock(new_inode, handle, &newfe_bh, 1);
		if (status < 0) {
			if (status != -ENOENT)
				mlog_errno(status);
			goto bail;
		}

		if (S_ISDIR(new_inode->i_mode))
			links_count = 0;
		else
			links_count = (unsigned int) (new_inode->i_nlink - 1);

		status = ocfs2_request_unlink_vote(new_inode, new_dentry,
						   links_count);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}

		newfe = (struct ocfs2_dinode *) newfe_bh->b_data;

		mlog(0, "aha rename over existing... new_de=%p "
		     "new_blkno=%"MLFu64" newfebh=%p bhblocknr=%llu\n",
		     new_de, newfe_blkno, newfe_bh, newfe_bh ?
		     (unsigned long long)newfe_bh->b_blocknr : 0ULL);

		if (S_ISDIR(new_inode->i_mode) || (new_inode->i_nlink == 1)) {
			status = ocfs2_prepare_orphan_dir(osb, handle,
							  new_inode,
							  orphan_name,
							  &orphan_entry_bh);
			if (status < 0) {
				mlog_errno(status);
				goto bail;
			}
		}
	} else {
		BUG_ON(new_dentry->d_parent->d_inode != new_dir);

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

		status = ocfs2_prepare_dir_for_insert(osb, new_dir, new_dir_bh,
						      new_dentry->d_name.name,
						      new_dentry->d_name.len,
						      &insert_entry_bh);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}
	}

	handle = ocfs2_start_trans(osb, handle, OCFS2_RENAME_CREDITS);
	if (IS_ERR(handle)) {
		status = PTR_ERR(handle);
		handle = NULL;
		mlog_errno(status);
		goto bail;
	}

	if (new_de) {
		if (S_ISDIR(new_inode->i_mode)) {
			if (!ocfs2_empty_dir(new_inode) ||
			    new_inode->i_nlink != 2) {
				status = -ENOTEMPTY;
				goto bail;
			}
		}
		status = ocfs2_journal_access(handle, new_inode, newfe_bh,
					      OCFS2_JOURNAL_ACCESS_WRITE);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}

		if (S_ISDIR(new_inode->i_mode) ||
		    (newfe->i_links_count == cpu_to_le16(1))){
			status = ocfs2_orphan_add(osb, handle, new_inode,
						  newfe, orphan_name,
						  orphan_entry_bh);
			if (status < 0) {
				mlog_errno(status);
				goto bail;
			}
		}

		/* change the dirent to point to the correct inode */
		status = ocfs2_journal_access(handle, new_dir, new_de_bh,
					      OCFS2_JOURNAL_ACCESS_WRITE);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}
		new_de->inode = cpu_to_le64(OCFS2_I(old_inode)->ip_blkno);
		new_de->file_type = old_de->file_type;
		new_dir->i_version++;
		status = ocfs2_journal_dirty(handle, new_de_bh);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}

		if (S_ISDIR(new_inode->i_mode))
			newfe->i_links_count = 0;
		else
			le16_add_cpu(&newfe->i_links_count, -1);

		status = ocfs2_journal_dirty(handle, newfe_bh);
		if (status < 0) {
			mlog_errno(status);
			goto bail;
		}
	} else {
		/* if the name was not found in new_dir, add it now */
		status = ocfs2_add_entry(handle, new_dentry, old_inode,
					 OCFS2_I(old_inode)->ip_blkno,
					 new_dir_bh, insert_entry_bh);
	}

	old_inode->i_ctime = CURRENT_TIME;
	mark_inode_dirty(old_inode);

	status = ocfs2_journal_access(handle, old_inode, old_inode_bh,
				      OCFS2_JOURNAL_ACCESS_WRITE);
	if (status >= 0) {
		oldfe = (struct ocfs2_dinode *) old_inode_bh->b_data;

		oldfe->i_ctime = cpu_to_le64(old_inode->i_ctime.tv_sec);
		oldfe->i_ctime_nsec = cpu_to_le32(old_inode->i_ctime.tv_nsec);

		status = ocfs2_journal_dirty(handle, old_inode_bh);
		if (status < 0)
			mlog_errno(status);
	} else
		mlog_errno(status);

	/* now that the name has been added to new_dir, remove the old name */
	status = ocfs2_delete_entry(handle, old_dir, old_de, old_de_bh);
	if (status < 0) {
		mlog_errno(status);
		goto bail;
	}

	if (new_inode) {
		new_inode->i_nlink--;
		new_inode->i_ctime = CURRENT_TIME;
	}
	old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME;
	if (old_inode_de_bh) {
		status = ocfs2_journal_access(handle, old_inode,
					     old_inode_de_bh,
					     OCFS2_JOURNAL_ACCESS_WRITE);
		PARENT_INO(old_inode_de_bh->b_data) =
			cpu_to_le64(OCFS2_I(new_dir)->ip_blkno);
		status = ocfs2_journal_dirty(handle, old_inode_de_bh);
		old_dir->i_nlink--;
		if (new_inode) {
			new_inode->i_nlink--;
		} else {
			new_dir->i_nlink++;
			mark_inode_dirty(new_dir);
		}
	}
	mark_inode_dirty(old_dir);
	ocfs2_mark_inode_dirty(handle, old_dir, old_dir_bh);
	if (new_inode) {
		mark_inode_dirty(new_inode);
		ocfs2_mark_inode_dirty(handle, new_inode, newfe_bh);
	}

	if (old_dir != new_dir) {
		/* Keep the same times on both directories.*/
		new_dir->i_ctime = new_dir->i_mtime = old_dir->i_ctime;

		/*
		 * This will also pick up the i_nlink change from the
		 * block above.
		 */
		ocfs2_mark_inode_dirty(handle, new_dir, new_dir_bh);
	}

	if (old_dir_nlink != old_dir->i_nlink) {
		if (!old_dir_bh) {
			mlog(ML_ERROR, "need to change nlink for old dir "
			     "%"MLFu64" from %d to %d but bh is NULL!\n",
			     OCFS2_I(old_dir)->ip_blkno,
			     (int)old_dir_nlink,
			     old_dir->i_nlink);
		} else {
			struct ocfs2_dinode *fe;
			status = ocfs2_journal_access(handle, old_dir,
						      old_dir_bh,
						      OCFS2_JOURNAL_ACCESS_WRITE);
			fe = (struct ocfs2_dinode *) old_dir_bh->b_data;
			fe->i_links_count = cpu_to_le16(old_dir->i_nlink);
			status = ocfs2_journal_dirty(handle, old_dir_bh);
		}
	}

	status = 0;
bail:
	if (rename_lock)
		ocfs2_rename_unlock(osb);

	if (handle)
		ocfs2_commit_trans(handle);

	if (new_inode)
		sync_mapping_buffers(old_inode->i_mapping);

	if (new_inode)
		iput(new_inode);
	if (newfe_bh)
		brelse(newfe_bh);
	if (old_inode_bh)
		brelse(old_inode_bh);
	if (old_dir_bh)
		brelse(old_dir_bh);
	if (new_dir_bh)
		brelse(new_dir_bh);
	if (new_de_bh)
		brelse(new_de_bh);
	if (old_de_bh)
		brelse(old_de_bh);
	if (old_inode_de_bh)
		brelse(old_inode_de_bh);
	if (orphan_entry_bh)
		brelse(orphan_entry_bh);
	if (insert_entry_bh)
		brelse(insert_entry_bh);

	mlog_exit(status);

	return status;
}

/*
 * we expect i_size = strlen(symname). Copy symname into the file
 * data, including the null terminator.
 */
static int ocfs2_create_symlink_data(struct ocfs2_super *osb,
				     struct ocfs2_journal_handle *handle,
				     struct inode *inode,
				     const char *symname)
{
	struct buffer_head **bhs = NULL;
	const char *c;
	struct super_block *sb = osb->sb;
	u64 p_blkno;
	int p_blocks;
	int virtual, blocks, status, i, bytes_left;

	bytes_left = i_size_read(inode) + 1;
	/* we can't trust i_blocks because we're actually going to
	 * write i_size + 1 bytes. */
	blocks = (bytes_left + sb->s_blocksize - 1) >> sb->s_blocksize_bits;

	mlog_entry("i_blocks = %lu, i_size = %llu, blocks = %d\n",
		   (unsigned long)inode->i_blocks, i_size_read(inode), blocks);

	/* Sanity check -- make sure we're going to fit. */
	if (bytes_left >
	    ocfs2_clusters_to_bytes(sb, OCFS2_I(inode)->ip_clusters)) {
		status = -EIO;
		mlog_errno(status);
		goto bail;
	}

	bhs = kcalloc(blocks, sizeof(struct buffer_head *), GFP_KERNEL);
	if (!bhs) {
		status = -ENOMEM;
		mlog_errno(status);
		goto bail;
	}

	status = ocfs2_extent_map_get_blocks(inode, 0, 1, &p_blkno,
					     &p_blocks);
	if (status < 0) {
		mlog_errno(status);
		goto bail;
	}

	/* links can never be larger than one cluster so we know this
	 * is all going to be contiguous, but do a sanity check
	 * 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;
	struct ocfs2_journal_handle *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);

	handle = ocfs2_alloc_handle(osb);
	if (handle == NULL) {
		status = -ENOMEM;
		mlog_errno(status);
		goto bail;
	}

	/* lock the parent directory */
	status = ocfs2_meta_lock(dir, handle, &parent_fe_bh, 1);
	if (status < 0) {
		if (status != -ENOENT)
			mlog_errno(status);
		goto bail;
	}

	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, handle, &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, handle, 1, &data_ac);
		if (status < 0) {
			if (status != -ENOSPC)
				mlog_errno(status);
			goto bail;
		}
	}

	handle = ocfs2_start_trans(osb, handle, 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)) {
		inode->i_op = &ocfs2_symlink_inode_operations;
		status = ocfs2_extend_allocation(osb, inode, 1, new_fe_bh,
						 handle, data_ac, NULL, NULL);
		if (status < 0) {
			if (status != -ENOSPC && status != -EINTR) {
				mlog(ML_ERROR, "Failed to extend file to "
					       "%"MLFu64"\n",
				     newsize);
				mlog_errno(status);
				status = -ENOSPC;
			}
			goto bail;
		}
		i_size_write(inode, newsize);
		inode->i_blocks = ocfs2_align_bytes_to_sectors(newsize);
	} 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;
	}

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

int ocfs2_check_dir_entry(struct inode * dir,
			  struct ocfs2_dir_entry * de,
			  struct buffer_head * bh,
			  unsigned long offset)
{
	const char *error_msg = NULL;