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authorHuang Ying <ying.huang@intel.com>2017-09-06 16:22:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-06 17:27:27 -0700
commit98cc093cba1e925eb34963dedb5f1684f1bdb2f4 (patch)
tree1651b9aed181959b1f5bae885a81ca130de09162 /drivers/block/brd.c
parentf0eea189e8e969b66e03bac8a7d92888ba267854 (diff)
downloadlinux-98cc093cba1e925eb34963dedb5f1684f1bdb2f4.tar.bz2
block, THP: make block_device_operations.rw_page support THP
The .rw_page in struct block_device_operations is used by the swap subsystem to read/write the page contents from/into the corresponding swap slot in the swap device. To support the THP (Transparent Huge Page) swap optimization, the .rw_page is enhanced to support to read/write THP if possible. Link: http://lkml.kernel.org/r/20170724051840.2309-6-ying.huang@intel.com Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c] Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vishal L Verma <vishal.l.verma@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shli@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/block/brd.c')
-rw-r--r--drivers/block/brd.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 104b71c0490d..5d9ed0616413 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -326,7 +326,11 @@ static int brd_rw_page(struct block_device *bdev, sector_t sector,
struct page *page, bool is_write)
{
struct brd_device *brd = bdev->bd_disk->private_data;
- int err = brd_do_bvec(brd, page, PAGE_SIZE, 0, is_write, sector);
+ int err;
+
+ if (PageTransHuge(page))
+ return -ENOTSUPP;
+ err = brd_do_bvec(brd, page, PAGE_SIZE, 0, is_write, sector);
page_endio(page, is_write, err);
return err;
}