Re: [PATCH 00/12] block/bio, fs: convert put_page() to put_user_page*()

Bob Liu
2019-07-25T00:44:47Z

On 7/24/19 12:25 PM, john.hubbard@gmail.com wrote:
> From: John Hubbard <jhubbard@nvidia.com>
>
> Hi,
>
> This is mostly Jerome's work, converting the block/bio and related areas
> to call put_user_page*() instead of put_page(). Because I've changed
> Jerome's patches, in some cases significantly, I'd like to get his
> feedback before we actually leave him listed as the author (he might
> want to disown some or all of these).
>

Could you add some background to the commit log for people don't have the context..
Why this converting? What's the main differences?

Regards, -Bob

> I added a new patch, in order to make this work with Christoph Hellwig's
> recent overhaul to bio_release_pages(): "block: bio_release_pages: use
> flags arg instead of bool".
>
> I've started the series with a patch that I've posted in another
> series ("mm/gup: add make_dirty arg to put_user_pages_dirty_lock()"[1]),
> because I'm not sure which of these will go in first, and this allows each
> to stand alone.
>
> Testing: not much beyond build and boot testing has been done yet. And
> I'm not set up to even exercise all of it (especially the IB parts) at
> run time.
>
> Anyway, changes here are:
>
> * Store, in the iov_iter, a "came from gup (get_user_pages)" parameter.
> Then, use the new iov_iter_get_pages_use_gup() to retrieve it when
> it is time to release the pages. That allows choosing between put_page()
> and put_user_page*().
>
> * Pass in one more piece of information to bio_release_pages: a "from_gup"
> parameter. Similar use as above.
>
> * Change the block layer, and several file systems, to use
> put_user_page*().
>
> [1] https://urldefense.proofpoint.com/v2/url?u=https-3A__lore.kernel.org_r_20190724012606.25844-2D2-2Djhubbard-40nvidia.com&d=DwIDaQ&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=1ktT0U2YS_I8Zz2o-MS1YcCAzWZ6hFGtyTgvVMGM7gI&m=FpFhv2rjbKCAYGmO6Hy8WJAottr1Qz_mDKDLObQ40FU&s=q-_mX3daEr22WbdZMElc_ZbD8L9oGLD7U0xLeyJ661Y&e=
> And please note the correction email that I posted as a follow-up,
> if you're looking closely at that patch. :) The fixed version is
> included here.
>
> John Hubbard (3):
> mm/gup: add make_dirty arg to put_user_pages_dirty_lock()
> block: bio_release_pages: use flags arg instead of bool
> fs/ceph: fix a build warning: returning a value from void function
>
> Jérôme Glisse (9):
> iov_iter: add helper to test if an iter would use GUP v2
> block: bio_release_pages: convert put_page() to put_user_page*()
> block_dev: convert put_page() to put_user_page*()
> fs/nfs: convert put_page() to put_user_page*()
> vhost-scsi: convert put_page() to put_user_page*()
> fs/cifs: convert put_page() to put_user_page*()
> fs/fuse: convert put_page() to put_user_page*()
> fs/ceph: convert put_page() to put_user_page*()
> 9p/net: convert put_page() to put_user_page*()
>
> block/bio.c | 81 ++++++++++++---
> drivers/infiniband/core/umem.c | 5 +-
> drivers/infiniband/hw/hfi1/user_pages.c | 5 +-
> drivers/infiniband/hw/qib/qib_user_pages.c | 5 +-
> drivers/infiniband/hw/usnic/usnic_uiom.c | 5 +-
> drivers/infiniband/sw/siw/siw_mem.c | 8 +-
> drivers/vhost/scsi.c | 13 ++-
> fs/block_dev.c | 22 +++-
> fs/ceph/debugfs.c | 2 +-
> fs/ceph/file.c | 62 ++++++++---
> fs/cifs/cifsglob.h | 3 +
> fs/cifs/file.c | 22 +++-
> fs/cifs/misc.c | 19 +++-
> fs/direct-io.c | 2 +-
> fs/fuse/dev.c | 22 +++-
> fs/fuse/file.c | 53 +++++++---
> fs/nfs/direct.c | 10 +-
> include/linux/bio.h | 22 +++-
> include/linux/mm.h | 5 +-
> include/linux/uio.h | 11 ++
> mm/gup.c | 115 +++++++++------------
> net/9p/trans_common.c | 14 ++-
> net/9p/trans_common.h | 3 +-
> net/9p/trans_virtio.c | 18 +++-
> 24 files changed, 357 insertions(+), 170 deletions(-)
>