[PATCH v2 11/11] xen/arm: call dma_to_phys on the dma_addr_t parameter of dma_cache_maint

From: Stefano Stabellini <sstabellini@kernel.org>
To: jgross@suse.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com
Cc: sstabellini@kernel.org, xen-devel@lists.xenproject.org,
	linux-kernel@vger.kernel.org, tamas@tklengyel.com,
	roman@zededa.com,
	Stefano Stabellini <stefano.stabellini@xilinx.com>
Subject: [PATCH v2 11/11] xen/arm: call dma_to_phys on the dma_addr_t parameter of dma_cache_maint
Date: Wed,  3 Jun 2020 15:22:47 -0700	[thread overview]
Message-ID: <20200603222247.11681-11-sstabellini@kernel.org> (raw)
In-Reply-To: <alpine.DEB.2.21.2006031506590.6774@sstabellini-ThinkPad-T480s>

From: Stefano Stabellini <stefano.stabellini@xilinx.com>

dma_cache_maint is getting called passing a dma address which could be
different from a physical address.

Add a struct device* parameter to dma_cache_maint.

Translate the dma_addr_t parameter of dma_cache_maint by calling
dma_to_phys. Do it for the first page and all the following pages, in
case of multipage handling.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Tested-by: Corey Minyard <cminyard@mvista.com>
Tested-by: Roman Shaposhnik <roman@zededa.com>
---
Changes in v2:
- improve commit message
---
 arch/arm/xen/mm.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index bbad712a890d..1dc20f4bdc33 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -43,15 +43,18 @@ unsigned long xen_get_swiotlb_free_pages(unsigned int order)
 static bool hypercall_cflush = false;
 
 /* buffers in highmem or foreign pages cannot cross page boundaries */
-static void dma_cache_maint(dma_addr_t handle, size_t size, u32 op)
+static void dma_cache_maint(struct device *dev, dma_addr_t handle,
+			    size_t size, u32 op)
 {
 	struct gnttab_cache_flush cflush;
 
-	cflush.a.dev_bus_addr = handle & XEN_PAGE_MASK;
 	cflush.offset = xen_offset_in_page(handle);
 	cflush.op = op;
+	handle &= XEN_PAGE_MASK;
 
 	do {
+		cflush.a.dev_bus_addr = dma_to_phys(dev, handle);
+
 		if (size + cflush.offset > XEN_PAGE_SIZE)
 			cflush.length = XEN_PAGE_SIZE - cflush.offset;
 		else
@@ -60,7 +63,7 @@ static void dma_cache_maint(dma_addr_t handle, size_t size, u32 op)
 		HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1);
 
 		cflush.offset = 0;
-		cflush.a.dev_bus_addr += cflush.length;
+		handle += cflush.length;
 		size -= cflush.length;
 	} while (size);
 }
@@ -79,7 +82,7 @@ void xen_dma_sync_for_cpu(struct device *dev, dma_addr_t handle,
 	if (pfn_valid(PFN_DOWN(dma_to_phys(dev, handle))))
 		arch_sync_dma_for_cpu(paddr, size, dir);
 	else if (dir != DMA_TO_DEVICE)
-		dma_cache_maint(handle, size, GNTTAB_CACHE_INVAL);
+		dma_cache_maint(dev, handle, size, GNTTAB_CACHE_INVAL);
 }
 
 void xen_dma_sync_for_device(struct device *dev, dma_addr_t handle,
@@ -89,9 +92,9 @@ void xen_dma_sync_for_device(struct device *dev, dma_addr_t handle,
 	if (pfn_valid(PFN_DOWN(dma_to_phys(dev, handle))))
 		arch_sync_dma_for_device(paddr, size, dir);
 	else if (dir == DMA_FROM_DEVICE)
-		dma_cache_maint(handle, size, GNTTAB_CACHE_INVAL);
+		dma_cache_maint(dev, handle, size, GNTTAB_CACHE_INVAL);
 	else
-		dma_cache_maint(handle, size, GNTTAB_CACHE_CLEAN);
+		dma_cache_maint(dev, handle, size, GNTTAB_CACHE_CLEAN);
 }
 
 bool xen_arch_need_swiotlb(struct device *dev,
-- 
2.17.1

