Unverified Commit acdbd67b authored by Konstantin Komarov's avatar Konstantin Komarov
Browse files

fs/ntfs3: Optimize large writes into sparse file 



Optimized cluster allocation by allocating a large chunk in advance
before writing, instead of allocating during the writing process
by clusters.
Essentially replicates the logic of fallocate.

Fixes: 4342306f ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: default avatarKonstantin Komarov <almaz.alexandrovich@paragon-software.com>
parent 2db86f79

fs/ntfs3/file.c

+36 −0
Original line number Diff line number Diff line
@@ -408,6 +408,42 @@ static int ntfs_extend(struct inode *inode, loff_t pos, size_t count, 
		err = 0;

	}



	if (file && is_sparsed(ni)) {

		/*

		 * This code optimizes large writes to sparse file.

		 * TODO: merge this fragment with fallocate fragment.

		 */

		struct ntfs_sb_info *sbi = ni->mi.sbi;

		CLST vcn = pos >> sbi->cluster_bits;

		CLST cend = bytes_to_cluster(sbi, end);

		CLST cend_v = bytes_to_cluster(sbi, ni->i_valid);

		CLST lcn, clen;

		bool new;



		if (cend_v > cend)

			cend_v = cend;



		/*

		 * Allocate and zero new clusters.

		 * Zeroing these clusters may be too long.

		 */

		for (; vcn < cend_v; vcn += clen) {

			err = attr_data_get_block(ni, vcn, cend_v - vcn, &lcn,

						  &clen, &new, true);

			if (err)

				goto out;

		}

		/*

		 * Allocate but not zero new clusters.

		 */

		for (; vcn < cend; vcn += clen) {

			err = attr_data_get_block(ni, vcn, cend - vcn, &lcn,

						  &clen, &new, false);

			if (err)

				goto out;

		}

	}



	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));

	mark_inode_dirty(inode);