Fred, I merged those patches as well the rebased dependent patches I took from your pnfs-block git tree - under pnfs-all-2.6.35-rc2-2010-06-12 Thanks! Benny On Jun. 11, 2010, 10:31 +0300, Fred Isaman <iisaman@xxxxxxxxxx> wrote: > This is version 2 of a patch series that limits LAYOUTGET invocation > to the beginning of the IO paths. It is intended for the pnfs_submit branch, > without reversion in a post_submit branch. > > Patches 1-4 revert direct IO. Commit is already broken, and this > series breaks them further. The problem is that the direct IO > redefines data->wb_req and data->pages, so that it can only work with > the pnfs code if we don't look at those fields. The reverted code should > be saved somewhere. I tend to agree with Boaz that keeping it in git is preferable, but I can supply a patch which returns the code ifdef'ed out if tht is preferred. > > Patches 5-9 do some code cleanup in preperation for the real work. > > Patches 10-21 implement the change. NOTE that patch 20 changes the > calling convention of the layout drivers commit calls. There is no > longer a universal lseg for the commit, instead each nfs_page has an > lseg attached, with NULL meaning to go through the MDS. > > Patches 22-26 rework the filelayout commit function, and then do some > other code cleanup. > > > > The basic idea of these patches is as follows: > > We attempt to grab a lseg (possibly invoking LAYOUTGET) early in the > IO. If we succeed, we refcount and stash it, using it through the > rest of the io. If we fail, we revert to straight nfs, even if the > area becomes covered by a layout due to other io. > > The tricky, though hopefully anomalous, case is when we start without > the layout, but have it at this particular stage of the IO. We ignore > this for the moment at write_pages, which will cause block and object > to issue CB_LAYOUTRECALL. At commit, it is tricky to handle, but > since block doesn't use commit, and file needs to handle complicated > splitting anyway, I just push all complicated decisions of splitting > commit between nfs (for IO started without layout) and pnfs to the > driver. > > Fred > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
