From mboxrd@z Thu Jan 1 00:00:00 1970 From: stefano.stabellini@eu.citrix.com (Stefano Stabellini) Date: Wed, 9 Oct 2013 21:48:29 +0100 Subject: [PATCH v8 16/17] arm, arm64: do not always merge biovec if we are running on Xen In-Reply-To: References: Message-ID: <1381351710-1876-16-git-send-email-stefano.stabellini@eu.citrix.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This is similar to what it is done on X86: biovecs are prevented from merging otherwise every dma requests would be forced to bounce on the swiotlb buffer. Signed-off-by: Stefano Stabellini Changes in v7: - remove the extra autotranslate check in biomerge.c. --- arch/arm/include/asm/io.h | 8 ++++++++ arch/arm64/include/asm/io.h | 9 +++++++++ 2 files changed, 17 insertions(+), 0 deletions(-) diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index d070741..c45effc 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h @@ -24,9 +24,11 @@ #ifdef __KERNEL__ #include +#include #include #include #include +#include /* * ISA I/O bus memory addresses are 1:1 with the physical address. @@ -372,6 +374,12 @@ extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr); #define BIOVEC_MERGEABLE(vec1, vec2) \ ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) +extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, + const struct bio_vec *vec2); +#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ + (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) && \ + (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))) + #ifdef CONFIG_MMU #define ARCH_HAS_VALID_PHYS_ADDR_RANGE extern int valid_phys_addr_range(phys_addr_t addr, size_t size); diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index 1d12f89..c163287b 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -22,11 +22,14 @@ #ifdef __KERNEL__ #include +#include #include #include #include +#include + /* * Generic IO read/write. These perform native-endian accesses. */ @@ -263,5 +266,11 @@ extern int devmem_is_allowed(unsigned long pfn); */ #define xlate_dev_kmem_ptr(p) p +extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, + const struct bio_vec *vec2); +#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ + (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) && \ + (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))) + #endif /* __KERNEL__ */ #endif /* __ASM_IO_H */ -- 1.7.2.5