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: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
---
fs/ntfs3/file.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
index cddc51f9a93b..d31eae611fe0 100644
--- a/fs/ntfs3/file.c
+++ b/fs/ntfs3/file.c
@@ -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);
--
2.34.1
