Re: [patch] truncate fixes

[Andrea Arcangeli <andrea@suse.de>]

On Sat, Jan 05, 2002 at 03:08:25AM -0800, Andrew Morton wrote:
>  	}
>  	return 0;
>  out:
> +	bh = head;
> +	block_start = 0;
> +	do {
> +		if (buffer_new(bh) && !buffer_uptodate(bh)) {
> +			memset(kaddr+block_start, 0, bh->b_size);
> +			set_bit(BH_Uptodate, &bh->b_state);
> +			mark_buffer_dirty(bh);
> +		}
> +		block_start += bh->b_size;
> +		bh = bh->b_this_page;
> +	} while (bh != head);
>  	return err;
>  }

the above code will end marking uptodate (zeroed) buffers relative to
blocks that cannot be read from disk. So a read-retry won't hit the disk
and that's wrong.

I think that will be fixed by additionally also return -EIO in the
wait_on_buffer loop (instead of goto out), so we won't generate zeroed
uptodate cache in case of read failure.

Andrea