The patch titled
Subject: goldish_pipe: convert to pin_user_pages() and put_user_page()
has been added to the -mm tree. Its filename is
goldish_pipe-convert-to-pin_user_pages-and-put_user_page.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/goldish_pipe-convert-to-pin_user_pages-and-put_user_page.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/goldish_pipe-convert-to-pin_user_pages-and-put_user_page.patch
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------------------------------------------------------
From: John Hubbard <jhubbard@xxxxxxxxxx>
Subject: goldish_pipe: convert to pin_user_pages() and put_user_page()
1. Call the new global pin_user_pages_fast(), from pin_goldfish_pages().
2. As required by pin_user_pages(), release these pages via
put_user_page(). In this case, do so via put_user_pages_dirty_lock().
That has the side effect of calling set_page_dirty_lock(), instead of
set_page_dirty(). This is probably more accurate.
As Christoph Hellwig put it, "set_page_dirty() is only safe if we are
dealing with a file backed page where we have reference on the inode it
hangs off." [1]
Another side effect is that the release code is simplified because the
page[] loop is now in gup.c instead of here, so just delete the local
release_user_pages() entirely, and call put_user_pages_dirty_lock()
directly, instead.
[1] https://lore.kernel.org/r/20190723153640.GB720@xxxxxx
Link: http://lkml.kernel.org/r/20191209225344.99740-12-jhubbard@xxxxxxxxxx
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Björn Töpel <bjorn.topel@xxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: "David S . Miller" <davem@xxxxxxxxxxxxx>
Cc: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Jerome Glisse <jglisse@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Cc: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/platform/goldfish/goldfish_pipe.c | 17 +++--------------
1 file changed, 3 insertions(+), 14 deletions(-)
--- a/drivers/platform/goldfish/goldfish_pipe.c~goldish_pipe-convert-to-pin_user_pages-and-put_user_page
+++ a/drivers/platform/goldfish/goldfish_pipe.c
@@ -274,7 +274,7 @@ static int goldfish_pin_pages(unsigned l
*iter_last_page_size = last_page_size;
}
- ret = get_user_pages_fast(first_page, requested_pages,
+ ret = pin_user_pages_fast(first_page, requested_pages,
!is_write ? FOLL_WRITE : 0,
pages);
if (ret <= 0)
@@ -285,18 +285,6 @@ static int goldfish_pin_pages(unsigned l
return ret;
}
-static void release_user_pages(struct page **pages, int pages_count,
- int is_write, s32 consumed_size)
-{
- int i;
-
- for (i = 0; i < pages_count; i++) {
- if (!is_write && consumed_size > 0)
- set_page_dirty(pages[i]);
- put_page(pages[i]);
- }
-}
-
/* Populate the call parameters, merging adjacent pages together */
static void populate_rw_params(struct page **pages,
int pages_count,
@@ -372,7 +360,8 @@ static int transfer_max_buffers(struct g
*consumed_size = pipe->command_buffer->rw_params.consumed_size;
- release_user_pages(pipe->pages, pages_count, is_write, *consumed_size);
+ put_user_pages_dirty_lock(pipe->pages, pages_count,
+ !is_write && *consumed_size > 0);
mutex_unlock(&pipe->lock);
return 0;
_
Patches currently in -mm which might be from jhubbard@xxxxxxxxxx are
mm-gup-factor-out-duplicate-code-from-four-routines.patch
mm-gup-move-try_get_compound_head-to-top-fix-minor-issues.patch
mm-devmap-refactor-1-based-refcounting-for-zone_device-pages.patch
goldish_pipe-rename-local-pin_user_pages-routine.patch
mm-fix-get_user_pages_remotes-handling-of-foll_longterm.patch
vfio-fix-foll_longterm-use-simplify-get_user_pages_remote-call.patch
mm-gup-allow-foll_force-for-get_user_pages_fast.patch
ib-umem-use-get_user_pages_fast-to-pin-dma-pages.patch
mm-gup-introduce-pin_user_pages-and-foll_pin.patch
goldish_pipe-convert-to-pin_user_pages-and-put_user_page.patch
ib-corehwumem-set-foll_pin-via-pin_user_pages-fix-up-odp.patch
mm-process_vm_access-set-foll_pin-via-pin_user_pages_remote.patch
drm-via-set-foll_pin-via-pin_user_pages_fast.patch
fs-io_uring-set-foll_pin-via-pin_user_pages.patch
net-xdp-set-foll_pin-via-pin_user_pages.patch
media-v4l2-core-set-pages-dirty-upon-releasing-dma-buffers.patch
media-v4l2-core-pin_user_pages-foll_pin-and-put_user_page-conversion.patch
vfio-mm-pin_user_pages-foll_pin-and-put_user_page-conversion.patch
powerpc-book3s64-convert-to-pin_user_pages-and-put_user_page.patch
powerpc-book3s64-convert-to-pin_user_pages-and-put_user_page-fix.patch
mm-gup_benchmark-use-proper-foll_write-flags-instead-of-hard-coding-1.patch
mm-tree-wide-rename-put_user_page-to-unpin_user_page.patch
mm-gup-pass-flags-arg-to-__gup_device_-functions.patch
mm-gup-track-foll_pin-pages.patch
mm-gup_benchmark-support-pin_user_pages-and-related-calls.patch
selftests-vm-run_vmtests-invoke-gup_benchmark-with-basic-foll_pin-coverage.patch
