[PATCHv7 3/5] common: dma-mapping: Introduce common remapping functions
From: James Hogan <hidden>
Date: 2014-08-27 09:30:18
Also in:
linux-mm, linux-next, lkml
On 26/08/14 17:58, Laura Abbott wrote:
On 8/26/2014 3:05 AM, James Hogan wrote:quoted
On 12 August 2014 00:40, Laura Abbott [off-list ref] wrote:quoted
For architectures without coherent DMA, memory for DMA may need to be remapped with coherent attributes. Factor out the the remapping code from arm and put it in a common location to reduce code duplication. As part of this, the arm APIs are now migrated away from ioremap_page_range to the common APIs which use map_vm_area for remapping. This should be an equivalent change and using map_vm_area is more correct as ioremap_page_range is intended to bring in io addresses into the cpu space and not regular kernel managed memory. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Laura Abbott <redacted>This commit in linux-next () breaks the build for metag: drivers/base/dma-mapping.c: In function ?dma_common_contiguous_remap?: drivers/base/dma-mapping.c:294: error: implicit declaration of function ?dma_common_pages_remap? drivers/base/dma-mapping.c:294: warning: assignment makes pointer from integer without a cast drivers/base/dma-mapping.c: At top level: drivers/base/dma-mapping.c:308: error: conflicting types for ?dma_common_pages_remap? drivers/base/dma-mapping.c:294: error: previous implicit declaration of ?dma_common_pages_remap? was here Looks like metag isn't alone either: $ git grep -L dma-mapping-common arch/*/include/asm/dma-mapping.h arch/arc/include/asm/dma-mapping.h arch/avr32/include/asm/dma-mapping.h arch/blackfin/include/asm/dma-mapping.h arch/c6x/include/asm/dma-mapping.h arch/cris/include/asm/dma-mapping.h arch/frv/include/asm/dma-mapping.h arch/m68k/include/asm/dma-mapping.h arch/metag/include/asm/dma-mapping.h arch/mn10300/include/asm/dma-mapping.h arch/parisc/include/asm/dma-mapping.h arch/xtensa/include/asm/dma-mapping.h I've checked a couple of these arches (blackfin, xtensa) which don't include dma-mapping-common.h and their builds seem to be broken too. Cheers JamesThanks for the report. Would you mind giving the following patch a test (this is theoretical only but I think it should work)
It certainly fixes the build for metag. Thanks James
quoted hunk ↗ jump to hunk
-----8<------ From 81c9a5504cbc1d72ff1df084d48502b248cd79d0 Mon Sep 17 00:00:00 2001 From: Laura Abbott <redacted> Date: Tue, 26 Aug 2014 09:50:49 -0700 Subject: [PATCH] common: dma-mapping: Swap function order Fix the order of dma_common_contiguous_remap and dma_common_pages_remap to avoid function declaration errors: drivers/base/dma-mapping.c: In function 'dma_common_contiguous_remap': drivers/base/dma-mapping.c:294: error: implicit declaration of function 'dma_common_pages_remap' drivers/base/dma-mapping.c:294: warning: assignment makes pointer from integer without a cast drivers/base/dma-mapping.c: At top level: drivers/base/dma-mapping.c:308: error: conflicting types for 'dma_common_pages_remap' drivers/base/dma-mapping.c:294: error: previous implicit declaration of 'dma_common_pages_remap' was here Change-Id: I65db739114e8f5816a24a279a2ff1a6dc92e2b83 Reported-by: James Hogan <redacted> Reported-by: kbuild test robot <redacted> Signed-off-by: Laura Abbott <redacted> --- drivers/base/dma-mapping.c | 44 ++++++++++++++++++++++---------------------- 1 file changed, 22 insertions(+), 22 deletions(-)diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c index 1bc46df..056fd46 100644 --- a/drivers/base/dma-mapping.c +++ b/drivers/base/dma-mapping.c@@ -271,6 +271,28 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, EXPORT_SYMBOL(dma_common_mmap); /* + * remaps an array of PAGE_SIZE pages into another vm_area + * Cannot be used in non-sleeping contexts + */ +void *dma_common_pages_remap(struct page **pages, size_t size, + unsigned long vm_flags, pgprot_t prot, + const void *caller) +{ + struct vm_struct *area; + + area = get_vm_area_caller(size, vm_flags, caller); + if (!area) + return NULL; + + if (map_vm_area(area, prot, pages)) { + vunmap(area->addr); + return NULL; + } + + return area->addr; +} + +/* * remaps an allocated contiguous region into another vm_area. * Cannot be used in non-sleeping contexts */@@ -299,28 +321,6 @@ void *dma_common_contiguous_remap(struct page *page, size_t size, } /* - * remaps an array of PAGE_SIZE pages into another vm_area - * Cannot be used in non-sleeping contexts - */ -void *dma_common_pages_remap(struct page **pages, size_t size, - unsigned long vm_flags, pgprot_t prot, - const void *caller) -{ - struct vm_struct *area; - - area = get_vm_area_caller(size, vm_flags, caller); - if (!area) - return NULL; - - if (map_vm_area(area, prot, pages)) { - vunmap(area->addr); - return NULL; - } - - return area->addr; -} - -/* * unmaps a range previously mapped by dma_common_*_remap */ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)