On 03/26/2015 02:34 PM, Ming Lin-SSI wrote: >> -----Original Message----- >> From: Jens Axboe [mailto:ax...@fb.com] >> Sent: Wednesday, March 25, 2015 8:08 AM >> To: linux-kernel@vger.kernel.org; linux-fsde...@vger.kernel.org >> Cc: Ming Lin-SSI; da...@fromorbit.com; Jens Axboe >> Subject: [PATCH 7/7] ext4: add support for write stream IDs >> >> Signed-off-by: Jens Axboe <ax...@fb.com> >> --- >> fs/ext4/page-io.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index >> b24a2541a9ba..f642d0b87a32 100644 >> --- a/fs/ext4/page-io.c >> +++ b/fs/ext4/page-io.c >> @@ -390,6 +390,7 @@ submit_and_retry: >> ret = io_submit_init_bio(io, bh); >> if (ret) >> return ret; >> + bio_set_streamid(io->io_bio, inode_streamid(inode)); > > For "writeback" and "ordered" journal mode, it should be OK. > > But for "journal" journal mode, > Step1: data written to journal > Step2: data written from journal to fs > > Do we need other code to carry stream_id in step2?
For either mode, arguably the journal should be written with its own stream ID. But that's a subject that the filesystem guys need to tackle, once the support is one. For the case of maintaining stream ID when in data=journal mode and copying the data out, I doubt that a use case that anyone would care about. If they do, the ext4/3 guys would need to sort that out. I'll update the commit message to reflect that, it is a bit under explained at the moment. -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
