f2fs: add a proc entry show disk layout

This patch adds the disk map of block address ranges configured by multiple
partitions.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/sysfs.c

@@ -1492,6 +1492,50 @@ static int __maybe_unused discard_plist_seq_show(struct seq_file *seq,
 	return 0;
 }
 
+static int __maybe_unused disk_map_seq_show(struct seq_file *seq,
+						void *offset)
+{
+	struct super_block *sb = seq->private;
+	struct f2fs_sb_info *sbi = F2FS_SB(sb);
+	int i;
+
+	seq_printf(seq, "Address Layout   : %5luB Block address (# of Segments)\n",
+					F2FS_BLKSIZE);
+	seq_printf(seq, " SB            : %12s\n", "0/1024B");
+	seq_printf(seq, " seg0_blkaddr  : 0x%010x\n", SEG0_BLKADDR(sbi));
+	seq_printf(seq, " Checkpoint    : 0x%010x (%10d)\n",
+			le32_to_cpu(F2FS_RAW_SUPER(sbi)->cp_blkaddr), 2);
+	seq_printf(seq, " SIT           : 0x%010x (%10d)\n",
+			SIT_I(sbi)->sit_base_addr,
+			le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment_count_sit));
+	seq_printf(seq, " NAT           : 0x%010x (%10d)\n",
+			NM_I(sbi)->nat_blkaddr,
+			le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment_count_nat));
+	seq_printf(seq, " SSA           : 0x%010x (%10d)\n",
+			SM_I(sbi)->ssa_blkaddr,
+			le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment_count_ssa));
+	seq_printf(seq, " Main          : 0x%010x (%10d)\n",
+			SM_I(sbi)->main_blkaddr,
+			le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment_count_main));
+	seq_printf(seq, " # of Sections : %12d\n",
+			le32_to_cpu(F2FS_RAW_SUPER(sbi)->section_count));
+	seq_printf(seq, " Segs/Sections : %12d\n",
+			SEGS_PER_SEC(sbi));
+	seq_printf(seq, " Section size  : %12d MB\n",
+			SEGS_PER_SEC(sbi) << 1);
+
+	if (!f2fs_is_multi_device(sbi))
+		return 0;
+
+	seq_puts(seq, "\nDisk Map for multi devices:\n");
+	for (i = 0; i < sbi->s_ndevs; i++)
+		seq_printf(seq, "Disk:%2d (zoned=%d): 0x%010x - 0x%010x on %s\n",
+			i, bdev_is_zoned(FDEV(i).bdev),
+			FDEV(i).start_blk, FDEV(i).end_blk,
+			FDEV(i).path);
+	return 0;
+}
+
 int __init f2fs_init_sysfs(void)
 {
 	int ret;
@@ -1573,6 +1617,8 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
 				victim_bits_seq_show, sb);
 	proc_create_single_data("discard_plist_info", 0444, sbi->s_proc,
 				discard_plist_seq_show, sb);
+	proc_create_single_data("disk_map", 0444, sbi->s_proc,
+				disk_map_seq_show, sb);
 	return 0;
 put_feature_list_kobj:
 	kobject_put(&sbi->s_feature_list_kobj);