[PATCH 21/34] dma-mapping: clear harmful GFP_* flags in common code

Christoph Hellwig
2018-01-12T08:42:19Z

Lift the code from x86 so that we behave consistently. In the future we
should probably warn if any of these is set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
---
arch/cris/arch-v32/drivers/pci/dma.c | 3 ---
arch/h8300/kernel/dma.c | 3 ---
arch/m68k/kernel/dma.c | 2 --
arch/mips/cavium-octeon/dma-octeon.c | 3 ---
arch/mips/loongson64/common/dma-swiotlb.c | 3 ---
arch/mips/mm/dma-default.c | 3 ---
arch/mips/netlogic/common/nlm-dma.c | 3 ---
arch/mn10300/mm/dma-alloc.c | 3 ---
arch/nios2/mm/dma-mapping.c | 3 ---
arch/powerpc/kernel/dma.c | 3 ---
arch/x86/kernel/pci-dma.c | 2 --
include/linux/dma-mapping.h | 7 +++++++
12 files changed, 7 insertions(+), 31 deletions(-)

diff --git a/arch/cris/arch-v32/drivers/pci/dma.c b/arch/cris/arch-v32/drivers/pci/dma.c
index dbbd3816cc0b..8c3802244ef3 100644
--- a/arch/cris/arch-v32/drivers/pci/dma.c
+++ b/arch/cris/arch-v32/drivers/pci/dma.c
@@ -22,9 +22,6 @@ static void *v32_dma_alloc(struct device *dev, size_t size,
{
void *ret;

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
gfp |= GFP_DMA;

diff --git a/arch/h8300/kernel/dma.c b/arch/h8300/kernel/dma.c
index 225dd0a188dc..d44ba5db4ac3 100644
--- a/arch/h8300/kernel/dma.c
+++ b/arch/h8300/kernel/dma.c
@@ -16,9 +16,6 @@ static void *dma_alloc(struct device *dev, size_t size,
{
void *ret;

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
if (dev == NULL || (*dev->dma_mask < 0xffffffff))
gfp |= GFP_DMA;
ret = (void *)__get_free_pages(gfp, get_order(size));
diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
index 87ef73a93856..c01b9b8f97bf 100644
--- a/arch/m68k/kernel/dma.c
+++ b/arch/m68k/kernel/dma.c
@@ -76,8 +76,6 @@ static void *m68k_dma_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
void *ret;
- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);

if (dev == NULL || (*dev->dma_mask < 0xffffffff))
gfp |= GFP_DMA;
diff --git a/arch/mips/cavium-octeon/dma-octeon.c b/arch/mips/cavium-octeon/dma-octeon.c
index c64bd87f0b6e..5baf79fce643 100644
--- a/arch/mips/cavium-octeon/dma-octeon.c
+++ b/arch/mips/cavium-octeon/dma-octeon.c
@@ -161,9 +161,6 @@ static void *octeon_dma_alloc_coherent(struct device *dev, size_t size,
{
void *ret;

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
if (IS_ENABLED(CONFIG_ZONE_DMA) && dev == NULL)
gfp |= __GFP_DMA;
else if (IS_ENABLED(CONFIG_ZONE_DMA) &&
diff --git a/arch/mips/loongson64/common/dma-swiotlb.c b/arch/mips/loongson64/common/dma-swiotlb.c
index ef07740cee61..15388c24a504 100644
--- a/arch/mips/loongson64/common/dma-swiotlb.c
+++ b/arch/mips/loongson64/common/dma-swiotlb.c
@@ -15,9 +15,6 @@ static void *loongson_dma_alloc_coherent(struct device *dev, size_t size,
{
void *ret;

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
if ((IS_ENABLED(CONFIG_ISA) && dev == NULL) ||
(IS_ENABLED(CONFIG_ZONE_DMA) &&
dev->coherent_dma_mask < DMA_BIT_MASK(32)))
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index e3e94d05f0fd..237532e89919 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -93,9 +93,6 @@ static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp)
{
gfp_t dma_flag;

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
#ifdef CONFIG_ISA
if (dev == NULL)
dma_flag = __GFP_DMA;
diff --git a/arch/mips/netlogic/common/nlm-dma.c b/arch/mips/netlogic/common/nlm-dma.c
index 0ec9d9da6d51..49c975b6aa28 100644
--- a/arch/mips/netlogic/common/nlm-dma.c
+++ b/arch/mips/netlogic/common/nlm-dma.c
@@ -47,9 +47,6 @@ static char *nlm_swiotlb;
static void *nlm_dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
#ifdef CONFIG_ZONE_DMA32
if (dev->coherent_dma_mask <= DMA_BIT_MASK(32))
gfp |= __GFP_DMA32;
diff --git a/arch/mn10300/mm/dma-alloc.c b/arch/mn10300/mm/dma-alloc.c
index 86108d2496b3..e3910d4db102 100644
--- a/arch/mn10300/mm/dma-alloc.c
+++ b/arch/mn10300/mm/dma-alloc.c
@@ -37,9 +37,6 @@ static void *mn10300_dma_alloc(struct device *dev, size_t size,
goto done;
}

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
gfp |= GFP_DMA;

diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
index 7040c1adbb5e..4be815519dd4 100644
--- a/arch/nios2/mm/dma-mapping.c
+++ b/arch/nios2/mm/dma-mapping.c
@@ -63,9 +63,6 @@ static void *nios2_dma_alloc(struct device *dev, size_t size,
{
void *ret;

- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
/* optimized page clearing */
gfp |= __GFP_ZERO;

diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index 6d5d04ccf3b4..76079841d3d0 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -105,9 +105,6 @@ void *__dma_nommu_alloc_coherent(struct device *dev, size_t size,
};
#endif /* CONFIG_FSL_SOC */

- /* ignore region specifiers */
- flag &= ~(__GFP_HIGHMEM);
-
page = alloc_pages_node(node, flag, get_order(size));
if (page == NULL)
return NULL;
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 8439e6de6156..61a8f1cb3829 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -87,7 +87,6 @@ void *dma_generic_alloc_coherent(struct device *dev, size_t size,

dma_mask = dma_alloc_coherent_mask(dev, flag);

- flag &= ~__GFP_ZERO;
again:
page = NULL;
/* CMA can be used only in the context which permits sleeping */
@@ -139,7 +138,6 @@ bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp)
if (!*dev)
*dev = &x86_dma_fallback_dev;

- *gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
*gfp = dma_alloc_coherent_gfp_flags(*dev, *gfp);

if (!is_device_dma_capable(*dev))
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 9f28b2fa329e..88bcb1a8211d 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -518,6 +518,13 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size,
if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
return cpu_addr;

+ /*
+ * Let the implementation decide on the zone to allocate from, and
+ * decide on the way of zeroing the memory given that the memory
+ * returned should always be zeroed.
+ */
+ flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM | __GFP_ZERO);
+
if (!arch_dma_alloc_attrs(&dev, &flag))
return NULL;
if (!ops->alloc)
--
2.14.2