summaryrefslogtreecommitdiffstats
path: root/drivers/ata
diff options
context:
space:
mode:
authorTycho Andersen <tycho@docker.com>2017-05-04 16:15:51 -0600
committerTejun Heo <tj@kernel.org>2017-05-16 11:23:16 -0400
commit5d7a288caf6d9b839a9a5bd28e56e15678669e67 (patch)
treee1546dd0e4b6e9f3efd85c781a16729815452be2 /drivers/ata
parenta95cfad947d5f40cfbf9ad3019575aac1d8ac7a6 (diff)
downloadlinux-5d7a288caf6d9b839a9a5bd28e56e15678669e67.tar.bz2
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>
Diffstat (limited to 'drivers/ata')
-rw-r--r--drivers/ata/libata-sff.c44
1 files changed, 8 insertions, 36 deletions
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 274d6d7193d7..baa24a9a0e68 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -716,24 +716,10 @@ static void ata_pio_sector(struct ata_queued_cmd *qc)
DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
- if (PageHighMem(page)) {
- unsigned long flags;
-
- /* FIXME: use a bounce buffer */
- local_irq_save(flags);
- buf = kmap_atomic(page);
-
- /* do the actual data transfer */
- ap->ops->sff_data_xfer(qc, buf + offset, qc->sect_size,
- do_write);
-
- kunmap_atomic(buf);
- local_irq_restore(flags);
- } else {
- buf = page_address(page);
- ap->ops->sff_data_xfer(qc, buf + offset, qc->sect_size,
- do_write);
- }
+ /* do the actual data transfer */
+ buf = kmap_atomic(page);
+ ap->ops->sff_data_xfer(qc, buf + offset, qc->sect_size, do_write);
+ kunmap_atomic(buf);
if (!do_write && !PageSlab(page))
flush_dcache_page(page);
@@ -861,24 +847,10 @@ next_sg:
DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
- if (PageHighMem(page)) {
- unsigned long flags;
-
- /* FIXME: use bounce buffer */
- local_irq_save(flags);
- buf = kmap_atomic(page);
-
- /* do the actual data transfer */
- consumed = ap->ops->sff_data_xfer(qc, buf + offset,
- count, rw);
-
- kunmap_atomic(buf);
- local_irq_restore(flags);
- } else {
- buf = page_address(page);
- consumed = ap->ops->sff_data_xfer(qc, buf + offset,
- count, rw);
- }
+ /* do the actual data transfer */
+ buf = kmap_atomic(page);
+ consumed = ap->ops->sff_data_xfer(qc, buf + offset, count, rw);
+ kunmap_atomic(buf);
bytes -= min(bytes, consumed);
qc->curbytes += count;