Commit 6a3b37e0 authored by Jan Kara's avatar Jan Kara
Browse files

udf: Push i_data_sem locking into udf_expand_file_adinicb() 



The checks we do in udf_setsize() and udf_file_write_iter() are safe to
do only with i_rwsem locked as it stabilizes both file type and file
size. Hence we don't need to lock i_data_sem before we enter
udf_expand_file_adinicb() which simplifies the locking somewhat.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent f950fd05

fs/udf/file.c

+5 −6
Original line number Diff line number Diff line
@@ -148,7 +148,6 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 
	if (retval <= 0)

		goto out;



	down_write(&iinfo->i_data_sem);

	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&

	    inode->i_sb->s_blocksize < (udf_file_entry_alloc_offset(inode) +

				 iocb->ki_pos + iov_iter_count(from))) {
@@ -158,15 +157,15 @@ static ssize_t udf_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 
			udf_debug("udf_expand_adinicb: err=%d\n", err);

			return err;

		}

	} else

		up_write(&iinfo->i_data_sem);

	}



	retval = __generic_file_write_iter(iocb, from);

out:

	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB && retval > 0) {

		down_write(&iinfo->i_data_sem);

	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB && retval > 0)

		iinfo->i_lenAlloc = inode->i_size;

		up_write(&iinfo->i_data_sem);

	}

	inode_unlock(inode);



	if (retval > 0) {

fs/udf/inode.c

+6 −12
Original line number Diff line number Diff line
@@ -247,7 +247,6 @@ const struct address_space_operations udf_aops = { 
/*

 * Expand file stored in ICB to a normal one-block-file

 *

 * This function requires i_data_sem for writing and releases it.

 * This function requires i_mutex held

 */

int udf_expand_file_adinicb(struct inode *inode)
@@ -259,6 +258,7 @@ int udf_expand_file_adinicb(struct inode *inode) 


	WARN_ON_ONCE(!inode_is_locked(inode));

	if (!iinfo->i_lenAlloc) {

		down_write(&iinfo->i_data_sem);

		if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_USE_SHORT_AD))

			iinfo->i_alloc_type = ICBTAG_FLAG_AD_SHORT;

		else
@@ -269,11 +269,6 @@ int udf_expand_file_adinicb(struct inode *inode) 
		mark_inode_dirty(inode);

		return 0;

	}

	/*

	 * Release i_data_sem so that we can lock a page - page lock ranks

	 * above i_data_sem. i_mutex still protects us against file changes.

	 */

	up_write(&iinfo->i_data_sem);



	page = find_or_create_page(inode->i_mapping, 0, GFP_NOFS);

	if (!page)
@@ -1160,19 +1155,18 @@ int udf_setsize(struct inode *inode, loff_t newsize) 


	iinfo = UDF_I(inode);

	if (newsize > inode->i_size) {

		down_write(&iinfo->i_data_sem);

		if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {

			if (bsize <

			if (bsize >=

			    (udf_file_entry_alloc_offset(inode) + newsize)) {

				err = udf_expand_file_adinicb(inode);

				if (err)

					return err;

				down_write(&iinfo->i_data_sem);

			} else {

				iinfo->i_lenAlloc = newsize;

				goto set_size;

			}

			err = udf_expand_file_adinicb(inode);

			if (err)

				return err;

		}

		down_write(&iinfo->i_data_sem);

		err = udf_extend_file(inode, newsize);

		if (err) {

			up_write(&iinfo->i_data_sem);