On Wed, 2013-01-16 at 19:25 +0100, Sedat Dilek wrote: > On Wed, Jan 16, 2013 at 5:32 PM, James Bottomley > <jbottomley@xxxxxxxxxxxxx> wrote: > > On Wed, 2013-01-09 at 13:58 -0600, Dave Kleikamp wrote: > >> This patchset was begun by Zach Brown and was originally submitted for > >> review in October, 2009. Feedback was positive, and I have picked up > >> where he left off, porting his patches to the latest mainline kernel > >> and adding support more file systems. > >> > >> This patch series adds a kernel interface to fs/aio.c so that kernel code can > >> issue concurrent asynchronous IO to file systems. It adds an aio command and > >> file system methods which specify io memory with pages instead of userspace > >> addresses. > >> > >> This series was written to reduce the current overhead loop imposes by > >> performing synchronus buffered file system IO from a kernel thread. These > >> patches turn loop into a light weight layer that translates bios into iocbs. > >> > >> It introduces new file ops, read_iter() and write_iter(), that replace the > >> aio_read() and aio_write() operations. The iov_iter structure can now contain > >> either a user-space iovec or a kernel-space bio_vec. Since it would be > >> overly complicated to replace every instance of aio_read() and aio_write(), > >> the old operations are not removed, but file systems implementing the new > >> ones need not keep the old ones. > >> > >> Changes from V4 include: > >> * moved iov-iter.c from mm/ to fs/ > >> * removed dio_aligned helper > >> * insured that FUA write to loop device is committed to media > >> * removed no-longer-used REQ_KERNEL define > >> > >> These patches apply to 3.8-rc2 and are also available at: > >> git://github.com/kleikamp/linux-shaggy.git loop_2013_01_04 > >> > >> My hopes are that this patchset is finally ready for linux-next. > > > > Just a note that we at parallels are anxiously awaiting this too. Our > > rewrite of the linux loop device to be more efficient (and not double > > cache) depends on this work. I should also note that we've been testing > > these patches (albeit backported to a RHEL kernel as a current work > > base) with no problems reported so far. > > > > Hi James, > > do you have a location for me for testing this patchset from parallels? You mean the RHEL kernels? Not really; they're just proof of concept and not released yet. Our mainline effort won't really begin until we know the fate of the DIO patches. James -- 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
