I/O priority "3". We can select the class between "rt" and "be",
                and set the I/O priority within valid range of it. "," delimiter
                is necessary in between I/O class and priority number.
+
+What:          /sys/fs/f2fs/<disk>/ovp_segments
+Date:          March 2021
+Contact:       "Jaegeuk Kim" <jaegeuk@kernel.org>
+Description:   Shows the number of overprovision segments.
 
                        (unsigned long long)(free_segments(sbi)));
 }
 
+static ssize_t ovp_segments_show(struct f2fs_attr *a,
+               struct f2fs_sb_info *sbi, char *buf)
+{
+       return sprintf(buf, "%llu\n",
+                       (unsigned long long)(overprovision_segments(sbi)));
+}
+
 static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
                struct f2fs_sb_info *sbi, char *buf)
 {
 F2FS_RW_ATTR(CPRC_INFO, ckpt_req_control, ckpt_thread_ioprio, ckpt_thread_ioprio);
 F2FS_GENERAL_RO_ATTR(dirty_segments);
 F2FS_GENERAL_RO_ATTR(free_segments);
+F2FS_GENERAL_RO_ATTR(ovp_segments);
 F2FS_GENERAL_RO_ATTR(lifetime_write_kbytes);
 F2FS_GENERAL_RO_ATTR(features);
 F2FS_GENERAL_RO_ATTR(current_reserved_blocks);
        ATTR_LIST(ckpt_thread_ioprio),
        ATTR_LIST(dirty_segments),
        ATTR_LIST(free_segments),
+       ATTR_LIST(ovp_segments),
        ATTR_LIST(unusable),
        ATTR_LIST(lifetime_write_kbytes),
        ATTR_LIST(features),