From mboxrd@z Thu Jan 1 00:00:00 1970 From: jim owens Subject: [RFC 00/12] btrfs core patches for direct I/O Date: Mon, 04 Jan 2010 16:11:04 -0500 Message-ID: <4B425968.4020308@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 To: linux-btrfs Return-path: List-ID: As if a Monday after a long holiday was not bad enough... this series has some simple patches in existing btrfs code that I want to make for btrfs directio code. The RESEND patches 1-5 were sent to Chris in December because IMO they have value without my directio code. You need them to apply some of the subsequent patches. IMO patch 6 is also of value independent of direct I/O, it reduces vmalloc use by 42K per worker, though we still use 268K per worker (ouch). Patches 7 - 12 don't have value without direct I/O. I'm sending them RFC as they can be understood by themselves, and they are much simpler than the directio code that uses them. :) Note - might as well explain this now as later when I send the big mess of dio.c for review. The existing core code for pagecache doesn't work for directio because the existing I/O routines depend on peeking inside a struct page to get the valid btrfs inode info. Sorry, no can do, we don't own that page. And rewriting the whole pagecache I/O stack to eliminate dependence on struct page would be too scary IMO. FWIW, fsx didn't crash on this series. jim