* [PATCH v2] ata-sff: always map page before data transfer
@ 2017-05-04 22:15 ` Tycho Andersen
0 siblings, 0 replies; 6+ messages in thread
From: Tycho Andersen @ 2017-05-04 22:15 UTC (permalink / raw)
To: Tejun Heo, Juerg Haefliger
Cc: Christoph Hellwig, linux-ide, linux-kernel, kernel-hardening,
Tycho Andersen
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
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tycho Andersen <tycho@docker.com>
CC: Juerg Haefliger <juerg.haefliger@hpe.com>
CC: Tejun Heo <tj@kernel.org>
[1]: https://lkml.org/lkml/2016/11/4/245
[2]: https://lkml.org/lkml/2016/11/4/253
---
v1: https://lkml.org/lkml/2017/5/2/404
---
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 2bd92dca3e62..01cf07c919bc 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 @@ static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
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;
--
2.11.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [kernel-hardening] [PATCH v2] ata-sff: always map page before data transfer
@ 2017-05-04 22:15 ` Tycho Andersen
0 siblings, 0 replies; 6+ messages in thread
From: Tycho Andersen @ 2017-05-04 22:15 UTC (permalink / raw)
To: Tejun Heo, Juerg Haefliger
Cc: Christoph Hellwig, linux-ide, linux-kernel, kernel-hardening,
Tycho Andersen
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
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tycho Andersen <tycho@docker.com>
CC: Juerg Haefliger <juerg.haefliger@hpe.com>
CC: Tejun Heo <tj@kernel.org>
[1]: https://lkml.org/lkml/2016/11/4/245
[2]: https://lkml.org/lkml/2016/11/4/253
---
v1: https://lkml.org/lkml/2017/5/2/404
---
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 2bd92dca3e62..01cf07c919bc 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 @@ static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
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;
--
2.11.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2] ata-sff: always map page before data transfer
2017-05-04 22:15 ` [kernel-hardening] " Tycho Andersen
@ 2017-05-05 6:31 ` Christoph Hellwig
-1 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2017-05-05 6:31 UTC (permalink / raw)
To: Tycho Andersen
Cc: Tejun Heo, Juerg Haefliger, Christoph Hellwig, linux-ide,
linux-kernel, kernel-hardening
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 6+ messages in thread
* [kernel-hardening] Re: [PATCH v2] ata-sff: always map page before data transfer
@ 2017-05-05 6:31 ` Christoph Hellwig
0 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2017-05-05 6:31 UTC (permalink / raw)
To: Tycho Andersen
Cc: Tejun Heo, Juerg Haefliger, Christoph Hellwig, linux-ide,
linux-kernel, kernel-hardening
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] ata-sff: always map page before data transfer
2017-05-04 22:15 ` [kernel-hardening] " Tycho Andersen
@ 2017-05-05 16:16 ` Tejun Heo
-1 siblings, 0 replies; 6+ messages in thread
From: Tejun Heo @ 2017-05-05 16:16 UTC (permalink / raw)
To: Tycho Andersen
Cc: Juerg Haefliger, Christoph Hellwig, linux-ide, linux-kernel,
kernel-hardening
On Thu, May 04, 2017 at 04:15:51PM -0600, Tycho Andersen wrote:
> 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
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Signed-off-by: Tycho Andersen <tycho@docker.com>
> CC: Juerg Haefliger <juerg.haefliger@hpe.com>
> CC: Tejun Heo <tj@kernel.org>
>
> [1]: https://lkml.org/lkml/2016/11/4/245
> [2]: https://lkml.org/lkml/2016/11/4/253
Yeah, it's a nice cleanup.
Applied to libata/for-4.13.
Thanks.
--
tejun
^ permalink raw reply [flat|nested] 6+ messages in thread
* [kernel-hardening] Re: [PATCH v2] ata-sff: always map page before data transfer
@ 2017-05-05 16:16 ` Tejun Heo
0 siblings, 0 replies; 6+ messages in thread
From: Tejun Heo @ 2017-05-05 16:16 UTC (permalink / raw)
To: Tycho Andersen
Cc: Juerg Haefliger, Christoph Hellwig, linux-ide, linux-kernel,
kernel-hardening
On Thu, May 04, 2017 at 04:15:51PM -0600, Tycho Andersen wrote:
> 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
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Signed-off-by: Tycho Andersen <tycho@docker.com>
> CC: Juerg Haefliger <juerg.haefliger@hpe.com>
> CC: Tejun Heo <tj@kernel.org>
>
> [1]: https://lkml.org/lkml/2016/11/4/245
> [2]: https://lkml.org/lkml/2016/11/4/253
Yeah, it's a nice cleanup.
Applied to libata/for-4.13.
Thanks.
--
tejun
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-05-05 16:16 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-05-04 22:15 [PATCH v2] ata-sff: always map page before data transfer Tycho Andersen
2017-05-04 22:15 ` [kernel-hardening] " Tycho Andersen
2017-05-05 6:31 ` Christoph Hellwig
2017-05-05 6:31 ` [kernel-hardening] " Christoph Hellwig
2017-05-05 16:16 ` Tejun Heo
2017-05-05 16:16 ` [kernel-hardening] " Tejun Heo
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.