On Fri, Oct 8, 2010 at 5:24 PM, Christoph Hellwig <hch@xxxxxx> wrote: > On Fri, Oct 08, 2010 at 05:14:27PM +0800, McPacino wrote: >> Hi Christoph, >> >> I have to take care the cache problem If using the bio directly. >> BHs can be released by kernel when necessary. >> >> Is there any existing code using bio to read/write metadata >> blocks? How do they handle the timing freeing bios? I really >> wish to learn something form it. > > If you actually need caching just use the pagecache, e.g. > read_mapping_page to read in your data. That completely abstracts > away the underlying block size. Hi Christoph, My understanding is that, read_mapping_page_async() works in submit-wait way. But whatI want is some function works in submit-callback way, just like sumbit_bh(). Is there something like it in kernel? thanks. cong meng. > > -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
