[dm-devel] Re: [patch] [2.6.12-rc6-mm1] Handle READA requests in dm-mpath.c

[Andrew Morton]

Lars Marowsky-Bree <lmb at suse.de> wrote:
>
> READA errors failing with EWOULDBLOCK/EAGAIN do not constitute a valid
> reason for failing the path; this lead to erratic errors on DM multipath
> devices. This error can be safely propagated upwards without failing the
> path.
> 

Why do you describe this as a -mm patch?  We want this in 2.6.12, no?

> --- linux-2.6.12-rc6-mm1.orig/drivers/md/dm-mpath.c	2005-06-08 12:51:02.741055000 +0200
> +++ linux-2.6.12-rc6-mm1/drivers/md/dm-mpath.c	2005-06-08 12:57:55.757828867 +0200
> @@ -985,6 +985,9 @@
>  	if (!error)
>  		return 0;	/* I/O complete */
>  
> +	if ((error == -EWOULDBLOCK) && bio_rw_ahead(bio))
> +		return error;
> +
>  	spin_lock(&m->lock);
>  	if (!m->nr_valid_paths) {
>  		if (!m->queue_if_no_path || m->suspended) {
> 
> 
> -- 
> High Availability & Clustering
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