From 5d7a288caf6d9b839a9a5bd28e56e15678669e67 Mon Sep 17 00:00:00 2001 From: Tycho Andersen Date: Thu, 4 May 2017 16:15:51 -0600 Subject: [PATCH] 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 Signed-off-by: Tycho Andersen CC: Juerg Haefliger Signed-off-by: Tejun Heo --- drivers/ata/libata-sff.c | 44 ++++++++-------------------------------- 1 file 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; -- 2.20.1