ata-sff: always map page before data transfer
authorTycho Andersen <tycho@docker.com>
Thu, 4 May 2017 22:15:51 +0000 (16:15 -0600)
committerTejun Heo <tj@kernel.org>
Tue, 16 May 2017 15:23:16 +0000 (11:23 -0400)
commit5d7a288caf6d9b839a9a5bd28e56e15678669e67
treee1546dd0e4b6e9f3efd85c781a16729815452be2
parenta95cfad947d5f40cfbf9ad3019575aac1d8ac7a6
ata-sff: always map page before data transfer

The XPFO [1] patchset may unmap pages from physmap if they happened to be
destined for userspace. If such a page is unmapped, it needs to be
remapped. Rather than test if a page is in the highmem/xpfo unmapped state,
Christoph suggested [2] that we simply always map the page.

v2: * drop comment about bounce buffer
    * don't save IRQs before kmap/unmap
    * formatting

[1]: https://lkml.org/lkml/2016/11/4/245
[2]: https://lkml.org/lkml/2016/11/4/253

Suggested-and-reviewed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tycho Andersen <tycho@docker.com>
CC: Juerg Haefliger <juerg.haefliger@hpe.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
drivers/ata/libata-sff.c