From: Christoph Hellwig <hch@lst.de>
To: iommu@lists.linux-foundation.org
Cc: Marek Szyprowski <m.szyprowski@samsung.com>,
Robin Murphy <robin.murphy@arm.com>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH 3/5] dma-direct: refine dma_direct_alloc zone selection
Date: Thu, 27 Sep 2018 15:35:37 -0700 [thread overview]
Message-ID: <20180927223539.28449-4-hch@lst.de> (raw)
In-Reply-To: <20180927223539.28449-1-hch@lst.de>
We need to take the DMA offset and encryption bit into account when
selecting a zone. User the opportunity to factor out the zone
selection into a helper for reuse.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
---
kernel/dma/direct.c | 31 +++++++++++++++++++++----------
1 file changed, 21 insertions(+), 10 deletions(-)
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index f32b33cfa331..e78548397a92 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -69,6 +69,22 @@ u64 dma_direct_get_required_mask(struct device *dev)
return (1ULL << (fls64(max_dma) - 1)) * 2 - 1;
}
+static gfp_t __dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
+ u64 *phys_mask)
+{
+ if (force_dma_unencrypted())
+ *phys_mask = __dma_to_phys(dev, dma_mask);
+ else
+ *phys_mask = dma_to_phys(dev, dma_mask);
+
+ /* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */
+ if (*phys_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
+ return GFP_DMA;
+ if (*phys_mask <= DMA_BIT_MASK(32))
+ return GFP_DMA32;
+ return 0;
+}
+
static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
{
return phys_to_dma_direct(dev, phys) + size - 1 <=
@@ -81,17 +97,13 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
int page_order = get_order(size);
struct page *page = NULL;
+ u64 phys_mask;
void *ret;
/* we always manually zero the memory once we are done: */
gfp &= ~__GFP_ZERO;
-
- /* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */
- if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
- gfp |= GFP_DMA;
- if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
- gfp |= GFP_DMA32;
-
+ gfp |= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
+ &phys_mask);
again:
/* CMA can be used only in the context which permits sleeping */
if (gfpflags_allow_blocking(gfp)) {
@@ -110,15 +122,14 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
page = NULL;
if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
- dev->coherent_dma_mask < DMA_BIT_MASK(64) &&
+ phys_mask < DMA_BIT_MASK(64) &&
!(gfp & (GFP_DMA32 | GFP_DMA))) {
gfp |= GFP_DMA32;
goto again;
}
if (IS_ENABLED(CONFIG_ZONE_DMA) &&
- dev->coherent_dma_mask < DMA_BIT_MASK(32) &&
- !(gfp & GFP_DMA)) {
+ phys_mask < DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) {
gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
goto again;
}
--
2.19.0
next prev parent reply other threads:[~2018-09-27 22:37 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-27 22:35 dma mask related fixups (including full bus_dma_mask support) v2 Christoph Hellwig
2018-09-27 22:35 ` [PATCH 1/5] dma-mapping: make the get_required_mask method available unconditionally Christoph Hellwig
2018-09-27 22:35 ` [PATCH 2/5] dma-direct: add an explicit dma_direct_get_required_mask Christoph Hellwig
2018-09-27 22:35 ` Christoph Hellwig [this message]
2018-09-27 22:35 ` [PATCH 4/5] dma-direct: implement complete bus_dma_mask handling Christoph Hellwig
2018-09-27 22:35 ` [PATCH 5/5] dma-direct: always allow dma mask <= physiscal memory size Christoph Hellwig
2018-10-03 23:10 ` Alexander Duyck
2018-10-09 5:01 ` Benjamin Herrenschmidt
2018-11-19 14:18 ` Ramon Fried
2018-11-19 15:50 ` Robin Murphy
2018-11-20 7:38 ` Ramon Fried
2018-10-01 14:32 ` dma mask related fixups (including full bus_dma_mask support) v2 Christoph Hellwig
2018-10-01 20:51 ` Benjamin Herrenschmidt
-- strict thread matches above, loose matches on Subject: below --
2018-09-20 18:52 dma mask related fixups (including full bus_dma_mask support) Christoph Hellwig
2018-09-20 18:52 ` [PATCH 3/5] dma-direct: refine dma_direct_alloc zone selection Christoph Hellwig
2018-09-27 1:45 ` Benjamin Herrenschmidt
2018-09-27 13:49 ` Christoph Hellwig
2018-09-28 0:06 ` Benjamin Herrenschmidt
2018-09-28 15:46 ` Christoph Hellwig
2018-09-27 14:30 ` Robin Murphy
2018-09-27 15:30 ` Christoph Hellwig
2018-09-27 15:38 ` Robin Murphy
2018-09-27 15:41 ` Christoph Hellwig
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