On Thu, 10 Aug 2006 16:13:33 -0400 Jeff Garzik <jeff@xxxxxxxxxx> wrote: > The sooner we kill buffer heads and use submit_bio(), the better :) A buffer_head is a caching entity and a bio is an IO container. They're quite separate concepts. A buffer_head is the kernel's sole abstraction of a disk block. Filesystems use disk blocks a lot, and they need such an abstraction. If one was to replace buffer_heads with direct-to-BIO operations then the filesytem would need to internally track the mapping from page+offset+length -> disk block and it would need to internally track the page+offset+length<->disk block coherency state and it would need to internally perform serialisation of access to each page+offset+length hunk of pagecache and etc and etc and etc. Create a data structure with which to do all that and voila, buffer_heads reinvented. - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
