Commit f4e222c5 authored Oct 03, 2017 by Jeff Layton Committed by Linus Torvalds Oct 03, 2017

mm: have filemap_check_and_advance_wb_err clear AS_EIO/AS_ENOSPC

Eryu noticed that he could sometimes get a leftover error reported when
it shouldn't be on fsync with ext2 and non-journalled ext4.

The problem is that writeback_single_inode still uses filemap_fdatawait.
That picks up a previously set AS_EIO flag, which would ordinarily have
been cleared before.

Since we're mostly using this function as a replacement for
filemap_check_errors, have filemap_check_and_advance_wb_err clear AS_EIO
and AS_ENOSPC when reporting an error.  That should allow the new
function to better emulate the behavior of the old with respect to these
flags.

Link: http://lkml.kernel.org/r/20170922133331.28812-1-jlayton@kernel.org


Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 5bdfca64

mm/filemap.c

+8 −0

Original line number	Original line	Diff line number	Diff line
	@@ -620,6 +620,14 @@ int file_check_and_advance_wb_err(struct file *file)
	trace_file_check_and_advance_wb_err(file, old);		trace_file_check_and_advance_wb_err(file, old);
	spin_unlock(&file->f_lock);		spin_unlock(&file->f_lock);
	}		}

			/*
			* We're mostly using this function as a drop in replacement for
			* filemap_check_errors. Clear AS_EIO/AS_ENOSPC to emulate the effect
			* that the legacy code would have had on these flags.
			*/
			clear_bit(AS_EIO, &mapping->flags);
			clear_bit(AS_ENOSPC, &mapping->flags);
	return err;		return err;
	}		}
	EXPORT_SYMBOL(file_check_and_advance_wb_err);		EXPORT_SYMBOL(file_check_and_advance_wb_err);

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