1 files changed, 13 insertions, 0 deletions

diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 5e4e78fc0b3a..616c075da062 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -30,6 +30,7 @@ typedef enum {
         attr_feature,
         attr_pointer_ui,
         attr_pointer_atomic,
+        attr_journal_task,
 } attr_id_t;
 
 typedef enum {
@@ -125,6 +126,14 @@ static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
         return count;
 }
 
+static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
+{
+        if (!sbi->s_journal)
+                return snprintf(buf, PAGE_SIZE, "<none>\n");
+        return snprintf(buf, PAGE_SIZE, "%d\n",
+                        task_pid_vnr(sbi->s_journal->j_task));
+}
+
 #define EXT4_ATTR(_name,_mode,_id)                                      \
 static struct ext4_attr ext4_attr_##_name = {                           \
         .attr = {.name = __stringify(_name), .mode = _mode },           \
@@ -188,6 +197,7 @@ EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
 EXT4_ATTR(first_error_time, 0444, first_error_time);
 EXT4_ATTR(last_error_time, 0444, last_error_time);
+EXT4_ATTR(journal_task, 0444, journal_task);
 
 static unsigned int old_bump_val = 128;
 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
@@ -217,6 +227,7 @@ static struct attribute *ext4_attrs[] = {
         ATTR_LIST(errors_count),
         ATTR_LIST(first_error_time),
         ATTR_LIST(last_error_time),
+        ATTR_LIST(journal_task),
         NULL,
 };
 
@@ -304,6 +315,8 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
                 return print_tstamp(buf, sbi->s_es, s_first_error_time);
         case attr_last_error_time:
                 return print_tstamp(buf, sbi->s_es, s_last_error_time);
+        case attr_journal_task:
+                return journal_task_show(sbi, buf);
         }
 
         return 0;