f2fs: compress: fix to update i_compr_blocks correctly

Previously, we account reserved blocks and compressed blocks into
@compr_blocks, then, f2fs_i_compr_blocks_update(,compr_blocks) will
update i_compr_blocks incorrectly, fix it.

Meanwhile, for the case all blocks in cluster were reserved, fix to
update dn->ofs_in_node correctly.

Fixes: eb8fbaa5 ("f2fs: compress: fix to check unreleased compressed cluster")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/file.c

@@ -3666,7 +3666,8 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count,
 
 	while (count) {
 		int compr_blocks = 0;
-		blkcnt_t reserved;
+		blkcnt_t reserved = 0;
+		blkcnt_t to_reserved;
 		int ret;
 
 		for (i = 0; i < cluster_size; i++) {
@@ -3686,20 +3687,26 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count,
 			 * fails in release_compress_blocks(), so NEW_ADDR
 			 * is a possible case.
 			 */
-			if (blkaddr == NEW_ADDR ||
-				__is_valid_data_blkaddr(blkaddr)) {
+			if (blkaddr == NEW_ADDR) {
+				reserved++;
+				continue;
+			}
+			if (__is_valid_data_blkaddr(blkaddr)) {
 				compr_blocks++;
 				continue;
 			}
 		}
 
-		reserved = cluster_size - compr_blocks;
+		to_reserved = cluster_size - compr_blocks - reserved;
 
 		/* for the case all blocks in cluster were reserved */
-		if (reserved == 1)
+		if (to_reserved == 1) {
+			dn->ofs_in_node += cluster_size;
 			goto next;
+		}
 
-		ret = inc_valid_block_count(sbi, dn->inode, &reserved, false);
+		ret = inc_valid_block_count(sbi, dn->inode,
+						&to_reserved, false);
 		if (unlikely(ret))
 			return ret;
 
@@ -3710,7 +3717,7 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count,
 
 		f2fs_i_compr_blocks_update(dn->inode, compr_blocks, true);
 
-		*reserved_blocks += reserved;
+		*reserved_blocks += to_reserved;
 next:
 		count -= cluster_size;
 	}