From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Stabellini Subject: [PATCH 2/2] xen/arm: introduce XENMEM_cache_flush Date: Thu, 2 Oct 2014 11:06:57 +0100 Message-ID: <1412244417-12251-2-git-send-email-stefano.stabellini@eu.citrix.com> References: Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: xen-devel@lists.xensource.com Cc: konrad.wilk@oracle.com, Ian.Campbell@citrix.com, david.vrabel@citrix.com, linux-kernel@vger.kernel.org, Stefano.Stabellini@eu.citrix.com, linux-arm-kernel@lists.infradead.org, Stefano Stabellini List-Id: xen-devel@lists.xenproject.org Introduce support for new hypercall XENMEM_cache_flush. Use it to perform cache flashing on pages used for dma when necessary. Signed-off-by: Stefano Stabellini --- arch/arm/xen/mm32.c | 19 ++++++++++++++++++- include/xen/interface/memory.h | 16 ++++++++++++++++ 2 files changed, 34 insertions(+), 1 deletion(-) diff --git a/arch/arm/xen/mm32.c b/arch/arm/xen/mm32.c index a5a93fc..aa45332 100644 --- a/arch/arm/xen/mm32.c +++ b/arch/arm/xen/mm32.c @@ -4,6 +4,9 @@ #include #include +#include + +#include /* functions called by SWIOTLB */ @@ -24,7 +27,21 @@ static void dma_cache_maint(dma_addr_t handle, unsigned long offset, if (!pfn_valid(pfn)) { - /* TODO: cache flush */ + struct xen_cache_flush cflush; + + cflush.op = 0; + cflush.addr = handle + offset; + cflush.size = size; + + if (op == dmac_unmap_area && dir != DMA_TO_DEVICE) + cflush.op = XENMEM_CACHE_INVAL; + if (op == dmac_map_area) { + cflush.op = XENMEM_CACHE_CLEAN; + if (dir == DMA_FROM_DEVICE) + cflush.op |= XENMEM_CACHE_INVAL; + } + if (cflush.op) + HYPERVISOR_memory_op(XENMEM_cache_flush, &cflush); } else { struct page *page = pfn_to_page(pfn); diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index 2ecfe4f..7d7e039 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -263,4 +263,20 @@ struct xen_remove_from_physmap { }; DEFINE_GUEST_HANDLE_STRUCT(xen_remove_from_physmap); +/* + * Issue one or more cache maintenance operations on a memory range + * owned by the calling domain or granted to the calling domain by a + * foreign domain. + */ +#define XENMEM_cache_flush 27 +struct xen_cache_flush { +/* addr is the machine address at the start of the memory range */ +uint64_t addr; +uint64_t size; +#define XENMEM_CACHE_CLEAN (1<<0) +#define XENMEM_CACHE_INVAL (1<<1) +uint32_t op; +}; +DEFINE_GUEST_HANDLE_STRUCT(xen_cache_flush); + #endif /* __XEN_PUBLIC_MEMORY_H__ */ -- 1.7.10.4