diff options
| author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2015-04-24 12:16:40 +0300 |
|---|---|---|
| committer | David Vrabel <david.vrabel@citrix.com> | 2015-05-06 17:02:58 +0300 |
| commit | 8746515d7f04c9ea94cf43e2db1fd2cfca93276d (patch) | |
| tree | d6770d527bfdffc9e9a4fe2f970304a547cde20d | |
| parent | a71dbdaa8ca2933391b08e0ae5567083e3af0892 (diff) | |
| download | linux-8746515d7f04c9ea94cf43e2db1fd2cfca93276d.tar.xz | |
xen: Add __GFP_DMA flag when xen_swiotlb_init gets free pages on ARM
Make sure that xen_swiotlb_init allocates buffers that are DMA capable
when at least one memblock is available below 4G. Otherwise we assume
that all devices on the SoC can cope with >4G addresses. We do this on
ARM and ARM64, where dom0 is mapped 1:1, so pfn == mfn in this case.
No functional changes on x86.
From: Chen Baozi <baozich@gmail.com>
Signed-off-by: Chen Baozi <baozich@gmail.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Chen Baozi <baozich@gmail.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
| -rw-r--r-- | arch/arm/include/asm/xen/page.h | 1 | ||||
| -rw-r--r-- | arch/arm/xen/mm.c | 15 | ||||
| -rw-r--r-- | arch/x86/include/asm/xen/page.h | 5 | ||||
| -rw-r--r-- | drivers/xen/swiotlb-xen.c | 2 |
4 files changed, 22 insertions, 1 deletions
diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h index 2f7e6ff67d51..0b579b2f4e0e 100644 --- a/arch/arm/include/asm/xen/page.h +++ b/arch/arm/include/asm/xen/page.h @@ -110,5 +110,6 @@ static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn) bool xen_arch_need_swiotlb(struct device *dev, unsigned long pfn, unsigned long mfn); +unsigned long xen_get_swiotlb_free_pages(unsigned int order); #endif /* _ASM_ARM_XEN_PAGE_H */ diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index 793551d15f1d..498325074a06 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -4,6 +4,7 @@ #include <linux/gfp.h> #include <linux/highmem.h> #include <linux/export.h> +#include <linux/memblock.h> #include <linux/of_address.h> #include <linux/slab.h> #include <linux/types.h> @@ -21,6 +22,20 @@ #include <asm/xen/hypercall.h> #include <asm/xen/interface.h> +unsigned long xen_get_swiotlb_free_pages(unsigned int order) +{ + struct memblock_region *reg; + gfp_t flags = __GFP_NOWARN; + + for_each_memblock(memory, reg) { + if (reg->base < (phys_addr_t)0xffffffff) { + flags |= __GFP_DMA; + break; + } + } + return __get_free_pages(flags, order); +} + enum dma_cache_op { DMA_UNMAP, DMA_MAP, diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 358dcd338915..c44a5d53e464 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -269,4 +269,9 @@ static inline bool xen_arch_need_swiotlb(struct device *dev, return false; } +static inline unsigned long xen_get_swiotlb_free_pages(unsigned int order) +{ + return __get_free_pages(__GFP_NOWARN, order); +} + #endif /* _ASM_X86_XEN_PAGE_H */ diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 810ad419e34c..4c549323c605 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -235,7 +235,7 @@ retry: #define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { - xen_io_tlb_start = (void *)__get_free_pages(__GFP_NOWARN, order); + xen_io_tlb_start = (void *)xen_get_swiotlb_free_pages(order); if (xen_io_tlb_start) break; order--; |