Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752635Ab3HBMke (ORCPT ); Fri, 2 Aug 2013 08:40:34 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:24918 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752476Ab3HBMkc (ORCPT ); Fri, 2 Aug 2013 08:40:32 -0400 Date: Fri, 2 Aug 2013 08:40:01 -0400 From: Konrad Rzeszutek Wilk To: Stefano Stabellini Cc: xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Ian.Campbell@citrix.com Subject: Re: [PATCH RFC 8/8] xen/arm,arm64: enable SWIOTLB_XEN Message-ID: <20130802124000.GJ24540@konrad-lan.dumpdata.com> References: <1375292732-7627-8-git-send-email-stefano.stabellini@eu.citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1375292732-7627-8-git-send-email-stefano.stabellini@eu.citrix.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8987 Lines: 287 On Wed, Jul 31, 2013 at 06:45:32PM +0100, Stefano Stabellini wrote: > Xen on arm and arm64 needs SWIOTLB_XEN: when running on Xen we need to > program the hardware with mfns rather than pfns for dma addresses. > Remove SWIOTLB_XEN dependency on X86 and PCI and make XEN select > SWIOTLB_XEN on arm and arm64. > > Implement xen_create_contiguous_region on arm and arm64 by using > XENMEM_get_dma_buf. > > Initialize the xen-swiotlb from xen_early_init (before the native > dma_ops are initialized), set dma_ops to &xen_swiotlb_dma_ops if we are > running on Xen. > > Signed-off-by: Stefano Stabellini > --- > arch/arm/Kconfig | 1 + > arch/arm/include/asm/xen/page.h | 2 + > arch/arm/xen/Makefile | 2 +- > arch/arm/xen/enlighten.c | 3 + > arch/arm/xen/mm.c | 118 +++++++++++++++++++++++++++++++++++++++ > arch/arm64/Kconfig | 1 + > arch/arm64/xen/Makefile | 2 +- > drivers/xen/Kconfig | 1 - > drivers/xen/swiotlb-xen.c | 18 ++++++ > 9 files changed, 145 insertions(+), 3 deletions(-) > create mode 100644 arch/arm/xen/mm.c > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 05125ab..72b53b9 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -1849,6 +1849,7 @@ config XEN > depends on CPU_V7 && !CPU_V6 > depends on !GENERIC_ATOMIC64 > select ARM_PSCI > + select SWIOTLB_XEN > help > Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. > > diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h > index 359a7b5..b0f7150 100644 > --- a/arch/arm/include/asm/xen/page.h > +++ b/arch/arm/include/asm/xen/page.h > @@ -6,12 +6,14 @@ > > #include > #include > +#include > > #include > > #define pfn_to_mfn(pfn) (pfn) > #define phys_to_machine_mapping_valid(pfn) (1) > #define mfn_to_pfn(mfn) (mfn) > +#define mfn_to_local_pfn(m) (mfn_to_pfn(m)) > #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) > > #define pte_mfn pte_pfn > diff --git a/arch/arm/xen/Makefile b/arch/arm/xen/Makefile > index 4384103..66fc35d 100644 > --- a/arch/arm/xen/Makefile > +++ b/arch/arm/xen/Makefile > @@ -1 +1 @@ > -obj-y := enlighten.o hypercall.o grant-table.o > +obj-y := enlighten.o hypercall.o grant-table.o mm.o > diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > index 14d17ab..06a6953 100644 > --- a/arch/arm/xen/enlighten.c > +++ b/arch/arm/xen/enlighten.c > @@ -195,6 +195,7 @@ static void xen_power_off(void) > * documentation of the Xen Device Tree format. > */ > #define GRANT_TABLE_PHYSADDR 0 > +extern int xen_mm_init(void); > void __init xen_early_init(void) > { > struct resource res; > @@ -230,6 +231,8 @@ void __init xen_early_init(void) > xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED; > else > xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED); > + > + xen_mm_init(); > } > > static int __init xen_guest_init(void) > diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c > new file mode 100644 > index 0000000..4ba1add > --- /dev/null > +++ b/arch/arm/xen/mm.c > @@ -0,0 +1,118 @@ > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > + > +#include > +#include > +#include > +#include > + > +static int xen_exchange_memory(xen_ulong_t extents_in, > + unsigned int order_in, > + xen_pfn_t *pfns_in, > + xen_ulong_t extents_out, > + unsigned int order_out, > + xen_pfn_t *mfns_out, > + unsigned int address_bits) > +{ > + long rc; > + int success; > + > + struct xen_memory_exchange exchange = { > + .in = { > + .nr_extents = extents_in, > + .extent_order = order_in, > + .domid = DOMID_SELF > + }, > + .out = { > + .nr_extents = extents_out, > + .extent_order = order_out, > + .address_bits = address_bits, > + .domid = DOMID_SELF > + } > + }; > + set_xen_guest_handle(exchange.in.extent_start, pfns_in); > + set_xen_guest_handle(exchange.out.extent_start, mfns_out); > + > + BUG_ON(extents_in << order_in != extents_out << order_out); > + > + > + rc = HYPERVISOR_memory_op(XENMEM_get_dma_buf, &exchange); > + success = (exchange.nr_exchanged == extents_in); > + > + BUG_ON(!success && ((exchange.nr_exchanged != 0) || (rc == 0))); > + BUG_ON(success && (rc != 0)); > + > + return success; > +} Could this code be made out to be more generic? It is almost the same on x86 - it just a different hypercall. > + > +int xen_create_contiguous_region(unsigned long vstart, unsigned int order, > + unsigned int address_bits, > + dma_addr_t *dma_handle) > +{ > + phys_addr_t pstart = __pa(vstart); > + xen_pfn_t in_frame, out_frame; > + int success, i; > + > + /* 2. Get a new contiguous memory extent. */ Step 1) is missing. > + in_frame = out_frame = pstart >> PAGE_SHIFT; > + success = xen_exchange_memory(1, order, &in_frame, > + 1, order, &out_frame, > + address_bits); > + > + if (!success) > + return -ENOMEM; > + > + *dma_handle = out_frame << PAGE_SHIFT; > + Ahem! Stray white-space > + return success ? 0 : -ENOMEM; > +} > +EXPORT_SYMBOL_GPL(xen_create_contiguous_region); > + > +void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) > +{ > + int i; > + xen_pfn_t in_frame = __pa(vstart) >> PAGE_SHIFT; > + struct xen_put_dma_buf buf = { > + .in = { > + .nr_extents = 1, > + .extent_order = order, > + .domid = DOMID_SELF > + }, > + }; > + set_xen_guest_handle(buf.in.extent_start, &in_frame); > + > + HYPERVISOR_memory_op(XENMEM_put_dma_buf, &buf); > +} > +EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); > + > +static struct dma_map_ops xen_swiotlb_dma_ops = { > + .mapping_error = xen_swiotlb_dma_mapping_error, > + .alloc = xen_swiotlb_alloc_coherent, > + .free = xen_swiotlb_free_coherent, > + .sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu, > + .sync_single_for_device = xen_swiotlb_sync_single_for_device, > + .sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu, > + .sync_sg_for_device = xen_swiotlb_sync_sg_for_device, > + .map_sg = xen_swiotlb_map_sg_attrs, > + .unmap_sg = xen_swiotlb_unmap_sg_attrs, > + .map_page = xen_swiotlb_map_page, > + .unmap_page = xen_swiotlb_unmap_page, > + .dma_supported = xen_swiotlb_dma_supported, > +}; > + > +int __init xen_mm_init(void) > +{ > + xen_swiotlb_init(1, true); > + dma_ops = &xen_swiotlb_dma_ops; > + return 0; > +} > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 9737e97..aa1f6fb 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -209,6 +209,7 @@ config XEN_DOM0 > config XEN > bool "Xen guest support on ARM64 (EXPERIMENTAL)" > depends on ARM64 && OF > + select SWIOTLB_XEN > help > Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. > > diff --git a/arch/arm64/xen/Makefile b/arch/arm64/xen/Makefile > index be24040..0ef9637 100644 > --- a/arch/arm64/xen/Makefile > +++ b/arch/arm64/xen/Makefile > @@ -1,2 +1,2 @@ > -xen-arm-y += $(addprefix ../../arm/xen/, enlighten.o grant-table.o) > +xen-arm-y += $(addprefix ../../arm/xen/, enlighten.o grant-table.o mm.o) > obj-y := xen-arm.o hypercall.o > diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig > index 9e02d60..7e83688 100644 > --- a/drivers/xen/Kconfig > +++ b/drivers/xen/Kconfig > @@ -140,7 +140,6 @@ config XEN_GRANT_DEV_ALLOC > > config SWIOTLB_XEN > def_bool y > - depends on PCI && X86 > select SWIOTLB > > config XEN_TMEM > diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c > index c79ac88..4ae6cf6 100644 > --- a/drivers/xen/swiotlb-xen.c > +++ b/drivers/xen/swiotlb-xen.c > @@ -59,6 +59,24 @@ static unsigned long xen_io_tlb_nslabs; > * Quick lookup value of the bus address of the IOTLB. > */ > > +#ifndef DMA_ERROR_CODE > +#define DMA_ERROR_CODE (~0) > +#endif > + > +#ifndef CONFIG_X86 > +static unsigned long dma_alloc_coherent_mask(struct device *dev, > + gfp_t gfp) > +{ > + unsigned long dma_mask = 0; > + > + dma_mask = dev->coherent_dma_mask; > + if (!dma_mask) > + dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32); > + > + return dma_mask; > +} > +#endif > + > struct xen_dma{ > dma_addr_t dma_addr; > phys_addr_t phys_addr; > -- > 1.7.2.5 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/