[PATCH v5 1/2] fscache,cachefiles: add prepare_ondemand_read() callback

[David Howells]

Jingbo Xu <jefflexu at linux.alibaba.com> wrote:

> Add prepare_ondemand_read() callback dedicated for the on-demand read
> scenario, so that callers from this scenario can be decoupled from
> netfs_io_subrequest.
> 
> The original cachefiles_prepare_read() is now refactored to a generic
> routine accepting a parameter list instead of netfs_io_subrequest.
> There's no logic change, except that the debug id of subrequest and
> request is removed from trace_cachefiles_prep_read().
> 
> Reviewed-by: Jeff Layton <jlayton at kernel.org>
> Signed-off-by: Jingbo Xu <jefflexu at linux.alibaba.com>

Acked-by: David Howells <dhowells at redhat.com>