From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762542AbZEHAh5 (ORCPT ); Thu, 7 May 2009 20:37:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762472AbZEHAR1 (ORCPT ); Thu, 7 May 2009 20:17:27 -0400 Received: from adsl-76-233-236-102.dsl.pltn13.sbcglobal.net ([76.233.236.102]:48342 "EHLO abulafia.goop.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932352AbZEHARW (ORCPT ); Thu, 7 May 2009 20:17:22 -0400 From: Jeremy Fitzhardinge To: Ingo Molnar Cc: FUJITA Tomonori , the arch/x86 maintainers , Linux Kernel Mailing List , Xen-devel , Jeremy Fitzhardinge , Jeremy Fitzhardinge Subject: [PATCH 1/9] xen: make sure swiotlb allocation is physically contigious Date: Thu, 7 May 2009 17:17:14 -0700 Message-Id: <1241741842-7966-2-git-send-email-jeremy@goop.org> X-Mailer: git-send-email 1.6.0.6 In-Reply-To: <1241741842-7966-1-git-send-email-jeremy@goop.org> References: <1241741842-7966-1-git-send-email-jeremy@goop.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Impact: make swiotlb allocation suitable for Xen When allocating the swiotlb buffer under Xen, make sure the memory is physically contiguous so that its really suitable for DMA. Do this by allocating the memory as usual, but then call a Xen function to rearrange the underlying pages to be physically contiguous. Signed-off-by: Jeremy Fitzhardinge Reviewed-by: "H. Peter Anvin" Cc: FUJITA Tomonori --- arch/x86/kernel/pci-swiotlb.c | 10 ---------- arch/x86/xen/Makefile | 1 + arch/x86/xen/pci-swiotlb.c | 27 +++++++++++++++++++++++++++ drivers/pci/xen-iommu.c | 16 ++++++++++++++++ include/xen/swiotlb.h | 6 ++++++ 5 files changed, 50 insertions(+), 10 deletions(-) create mode 100644 arch/x86/xen/pci-swiotlb.c create mode 100644 include/xen/swiotlb.h diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c index 34f12e9..bc09da7 100644 --- a/arch/x86/kernel/pci-swiotlb.c +++ b/arch/x86/kernel/pci-swiotlb.c @@ -13,16 +13,6 @@ int swiotlb __read_mostly; -void * __init swiotlb_alloc_boot(size_t size, unsigned long nslabs) -{ - return alloc_bootmem_low_pages(size); -} - -void *swiotlb_alloc(unsigned order, unsigned long nslabs) -{ - return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order); -} - dma_addr_t swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr) { return paddr; diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index c4cda96..caede49 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -12,3 +12,4 @@ obj-y := enlighten.o setup.o multicalls.o mmu.o irq.o \ obj-$(CONFIG_SMP) += smp.o spinlock.o obj-$(CONFIG_XEN_DEBUG_FS) += debugfs.o obj-$(CONFIG_XEN_DOM0) += vga.o +obj-$(CONFIG_PCI_XEN) += pci-swiotlb.o \ No newline at end of file diff --git a/arch/x86/xen/pci-swiotlb.c b/arch/x86/xen/pci-swiotlb.c new file mode 100644 index 0000000..25f0365 --- /dev/null +++ b/arch/x86/xen/pci-swiotlb.c @@ -0,0 +1,27 @@ +#include +#include + +#include +#include + +/* + * This file defines overrides for weak functions with default + * implementations in lib/swiotlb.c. + */ + +void * __init swiotlb_alloc_boot(size_t size, unsigned long nslabs) +{ + void *ret = alloc_bootmem_low_pages(size); + + if (ret && xen_pv_domain()) + xen_swiotlb_fixup(ret, size, nslabs); + + return ret; +} + +void *swiotlb_alloc(unsigned order, unsigned long nslabs) +{ + /* Never called on x86. Warn, just in case. */ + WARN_ON(1); + return NULL; +} diff --git a/drivers/pci/xen-iommu.c b/drivers/pci/xen-iommu.c index 32a8b49..c593058 100644 --- a/drivers/pci/xen-iommu.c +++ b/drivers/pci/xen-iommu.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include @@ -34,6 +35,21 @@ do { \ (unsigned long long)addr + size); \ } while (0) + +void xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs) +{ + unsigned order = get_order(size); + + printk(KERN_DEBUG "xen_swiotlb_fixup: buf=%p size=%zu order=%u\n", + buf, size, order); + + if (WARN_ON(size != (PAGE_SIZE << order))) + return; + + if (xen_create_contiguous_region((unsigned long)buf, + order, 0xffffffff)) + printk(KERN_ERR "xen_create_contiguous_region failed\n"); +} static inline int address_needs_mapping(struct device *hwdev, dma_addr_t addr) { diff --git a/include/xen/swiotlb.h b/include/xen/swiotlb.h new file mode 100644 index 0000000..67b7b42 --- /dev/null +++ b/include/xen/swiotlb.h @@ -0,0 +1,6 @@ +#ifndef _XEN_SWIOTLB_H +#define _XEN_SWIOTLB_H + +extern void xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs); + +#endif /* _XEN_SWIOTLB_H */ -- 1.6.0.6