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authorChristoph Hellwig <hch@lst.de>2016-01-21 00:01:22 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2016-01-21 02:09:18 +0100
commit0d4a619b64bad7117947a84a10c17a2b8f14d252 (patch)
tree07ce1a6bfc43b0e0fb54f3231923c1f893938ff8
parentiio: core: fix ptr_ret.cocci warnings (diff)
downloadlinux-0d4a619b64bad7117947a84a10c17a2b8f14d252.tar.xz
linux-0d4a619b64bad7117947a84a10c17a2b8f14d252.zip
dma-mapping: make the generic coherent dma mmap implementation optional
This series converts all remaining architectures to use dma_map_ops and the generic implementation of the DMA API. This not only simplifies the code a lot, but also prepares for possible future changes like more generic non-iommu dma_ops implementations or generic per-device dma_map_ops. This patch (of 16): We have a couple architectures that do not want to support this code, so add another Kconfig symbol that disables the code similar to what we do for the nommu case. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Steven Miao <realmz6@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Helge Deller <deller@gmx.de> Cc: James Hogan <james.hogan@imgtec.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Mark Salter <msalter@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
-rw-r--r--arch/Kconfig3
-rw-r--r--drivers/base/dma-mapping.c4
2 files changed, 5 insertions, 2 deletions
diff --git a/arch/Kconfig b/arch/Kconfig
index ba1b626bca00..51c03efb4083 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -632,4 +632,7 @@ config OLD_SIGACTION
config COMPAT_OLD_SIGACTION
bool
+config ARCH_NO_COHERENT_DMA_MMAP
+ bool
+
source "kernel/gcov/Kconfig"
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index d95c5971c225..381e39d5204e 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c
@@ -247,7 +247,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size)
{
int ret = -ENXIO;
-#ifdef CONFIG_MMU
+#if defined(CONFIG_MMU) && !defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP)
unsigned long user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
@@ -264,7 +264,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
user_count << PAGE_SHIFT,
vma->vm_page_prot);
}
-#endif /* CONFIG_MMU */
+#endif /* CONFIG_MMU && !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
return ret;
}