Merge tag 'perf-tools-fixes-for-v5.9-2020-09-03' of git://git.kernel.org/pub/scm...

[linux-2.6-microblaze.git] / fs / ext4 / ext4_jbd2.c

diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index 0c76cdd..760b9ee 100644 (file)
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -195,6 +195,28 @@ static void ext4_journal_abort_handle(const char *caller, unsigned int line,
        jbd2_journal_abort_handle(handle);
 }
 
+static void ext4_check_bdev_write_error(struct super_block *sb)
+{
+       struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
+       struct ext4_sb_info *sbi = EXT4_SB(sb);
+       int err;
+
+       /*
+        * If the block device has write error flag, it may have failed to
+        * async write out metadata buffers in the background. In this case,
+        * we could read old data from disk and write it out again, which
+        * may lead to on-disk filesystem inconsistency.
+        */
+       if (errseq_check(&mapping->wb_err, READ_ONCE(sbi->s_bdev_wb_err))) {
+               spin_lock(&sbi->s_bdev_wb_lock);
+               err = errseq_check_and_advance(&mapping->wb_err, &sbi->s_bdev_wb_err);
+               spin_unlock(&sbi->s_bdev_wb_lock);
+               if (err)
+                       ext4_error_err(sb, -err,
+                                      "Error while async write back metadata");
+       }
+}
+
 int __ext4_journal_get_write_access(const char *where, unsigned int line,
                                    handle_t *handle, struct buffer_head *bh)
 {
@@ -202,6 +224,9 @@ int __ext4_journal_get_write_access(const char *where, unsigned int line,
 
        might_sleep();
 
+       if (bh->b_bdev->bd_super)
+               ext4_check_bdev_write_error(bh->b_bdev->bd_super);
+
        if (ext4_handle_valid(handle)) {
                err = jbd2_journal_get_write_access(handle, bh);
                if (err)