f2fs: make gc_urgent and gc_segment_mode sysfs node readable

Changed a way of showing values of them to use strings.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: Daeho Jeong

fs/f2fs/sysfs.c

@@ -41,6 +41,16 @@ enum {
 	ATGC_INFO,	/* struct atgc_management */
 };
 
+static const char *gc_mode_names[MAX_GC_MODE] = {
+	"GC_NORMAL",
+	"GC_IDLE_CB",
+	"GC_IDLE_GREEDY",
+	"GC_IDLE_AT",
+	"GC_URGENT_HIGH",
+	"GC_URGENT_LOW",
+	"GC_URGENT_MID"
+};
+
 struct f2fs_attr {
 	struct attribute attr;
 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
@@ -316,8 +326,13 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 		return sysfs_emit(buf, "%u\n", sbi->compr_new_inode);
 #endif
 
+	if (!strcmp(a->attr.name, "gc_urgent"))
+		return sysfs_emit(buf, "%s\n",
+				gc_mode_names[sbi->gc_mode]);
+
 	if (!strcmp(a->attr.name, "gc_segment_mode"))
-		return sysfs_emit(buf, "%u\n", sbi->gc_segment_mode);
+		return sysfs_emit(buf, "%s\n",
+				gc_mode_names[sbi->gc_segment_mode]);
 
 	if (!strcmp(a->attr.name, "gc_reclaimed_segments")) {
 		return sysfs_emit(buf, "%u\n",