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dma-contiguous: fix !CONFIG_DMA_CMA version of dma_{alloc, free}_contiguous() 

Commit fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous()
helpers") adds a pair of new helper functions so as to abstract code in
the dma-direct (and other places in the future), however it breaks QEMU
boot feature using x86_64 defconfig.

That's because x86_64 defconfig has CONFIG_DMA_CMA=n so those two newly
introduced helper functions are empty in their !CONFIG_DMA_CMA version,
while previously the platform independent dma-direct code had fallback
alloc_pages_node() and __free_pages().

So this patch fixes it by adding alloc_pages_node() and __free_pages()
in the !CONFIG_DMA_CMA version of the two helper functions.

Tested with below QEMU command:
  qemu-system-x86_64 -m 512m \
      -drive file=images/x86_64/rootfs.ext4,format=raw,if=ide \
      -append 'console=ttyS0 root=/dev/sda' -nographic \
      -kernel arch/x86_64/boot/bzImage

with the rootfs from the below link:
  https://github.com/ClangBuiltLinux/continuous-integration/raw/master/images/x86_64/rootfs.ext4

Fixes: fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Nicolin Chen 2019-05-29 17:54:25 -07:00 committed by Christoph Hellwig
parent bd2e75633c
commit dd3dcede9f
1 changed files with 7 additions and 1 deletions
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8
include/linux/dma-contiguous.h
View File

@ -50,6 +50,7 @@
#ifdef __KERNEL__ #ifdef __KERNEL__
#include <linux/device.h> #include <linux/device.h>
#include <linux/mm.h>
struct cma; struct cma;
struct page; struct page;
@ -155,15 +156,20 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
return false; return false;
} }
/* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */
static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size, static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size,
gfp_t gfp) gfp_t gfp)
{ {
return NULL; int node = dev ? dev_to_node(dev) : NUMA_NO_NODE;
size_t align = get_order(PAGE_ALIGN(size));
return alloc_pages_node(node, gfp, align);
} }
static inline void dma_free_contiguous(struct device *dev, struct page *page, static inline void dma_free_contiguous(struct device *dev, struct page *page,
size_t size) size_t size)
{ {
__free_pages(page, get_order(size));
} }
#endif #endif