ext4/jbd2: Avoid WARN() messages when failing to write to the superblock

This fixes some very common warnings reported by kerneloops.org

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 8175318..fb5766e 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2810,13 +2810,34 @@ static void ext4_commit_super(struct super_block *sb,
 
        if (!sbh)
                return;
+       if (buffer_write_io_error(sbh)) {
+               /*
+                * Oh, dear.  A previous attempt to write the
+                * superblock failed.  This could happen because the
+                * USB device was yanked out.  Or it could happen to
+                * be a transient write error and maybe the block will
+                * be remapped.  Nothing we can do but to retry the
+                * write and hope for the best.
+                */
+               printk(KERN_ERR "ext4: previous I/O error to "
+                      "superblock detected for %s.\n", sb->s_id);
+               clear_buffer_write_io_error(sbh);
+               set_buffer_uptodate(sbh);
+       }
        es->s_wtime = cpu_to_le32(get_seconds());
        ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
        es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
        BUFFER_TRACE(sbh, "marking dirty");
        mark_buffer_dirty(sbh);
-       if (sync)
+       if (sync) {
                sync_dirty_buffer(sbh);
+               if (buffer_write_io_error(sbh)) {
+                       printk(KERN_ERR "ext4: I/O error while writing "
+                              "superblock for %s.\n", sb->s_id);
+                       clear_buffer_write_io_error(sbh);
+                       set_buffer_uptodate(sbh);
+               }
+       }
 }
 
 

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 81186a2..01c3901 100644 (file)
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1255,6 +1255,22 @@ void jbd2_journal_update_superblock(journal_t *journal, int wait)
                goto out;
        }
 
+       if (buffer_write_io_error(bh)) {
+               /*
+                * Oh, dear.  A previous attempt to write the journal
+                * superblock failed.  This could happen because the
+                * USB device was yanked out.  Or it could happen to
+                * be a transient write error and maybe the block will
+                * be remapped.  Nothing we can do but to retry the
+                * write and hope for the best.
+                */
+               printk(KERN_ERR "JBD2: previous I/O error detected "
+                      "for journal superblock update for %s.\n",
+                      journal->j_devname);
+               clear_buffer_write_io_error(bh);
+               set_buffer_uptodate(bh);
+       }
+
        spin_lock(&journal->j_state_lock);
        jbd_debug(1,"JBD: updating superblock (start %ld, seq %d, errno %d)\n",
                  journal->j_tail, journal->j_tail_sequence, journal->j_errno);
@@ -1266,9 +1282,16 @@ void jbd2_journal_update_superblock(journal_t *journal, int wait)
 
        BUFFER_TRACE(bh, "marking dirty");
        mark_buffer_dirty(bh);
-       if (wait)
+       if (wait) {
                sync_dirty_buffer(bh);
-       else
+               if (buffer_write_io_error(bh)) {
+                       printk(KERN_ERR "JBD2: I/O error detected "
+                              "when updating journal superblock for %s.\n",
+                              journal->j_devname);
+                       clear_buffer_write_io_error(bh);
+                       set_buffer_uptodate(bh);
+               }
+       } else
                ll_rw_block(SWRITE, 1, &bh);
 
 out: