Re: Question regarding SLAB corruption

[Keir Fraser <keir@xensource.com>]

[-- Attachment #1: Type: text/plain, Size: 260 bytes --]

On 9/7/07 19:46, "Keir Fraser" <keir@xensource.com> wrote:

> Anyway, attahced is a patch I just applied to our unstable Linux tree. It
> should fix this issue.

And here's *another* patch. It applies on top of the previous one (ie. you
need both).

 -- Keir


[-- Attachment #2: swiotlb2.patch --]
[-- Type: application/octet-stream, Size: 2171 bytes --]

# HG changeset patch
# User kfraser@localhost.localdomain
# Date 1184008553 -3600
# Node ID 5684370b1c4d9911fd4118fdc472c3c7a9adfca3
# Parent  5a4e93508aa03799989b63f8413aeae7df87c576
swiotlb: Allow sync on arbitrary offsets into dma-mapped region.
Signed-off-by: Keir Fraser <keir@xensource.com>

diff -r 5a4e93508aa0 -r 5684370b1c4d arch/i386/kernel/swiotlb.c
--- a/arch/i386/kernel/swiotlb.c	Mon Jul 09 20:00:19 2007 +0100
+++ b/arch/i386/kernel/swiotlb.c	Mon Jul 09 20:15:53 2007 +0100
@@ -378,17 +378,25 @@ map_single(struct device *hwdev, struct 
 	 */
 	slot_buf = buffer;
 	for (i = 0; i < nslots; i++) {
+		slot_buf.page += slot_buf.offset >> PAGE_SHIFT;
+		slot_buf.offset &= PAGE_SIZE - 1;
 		io_tlb_orig_addr[index+i] = slot_buf;
 		slot_buf.offset += 1 << IO_TLB_SHIFT;
-		if (slot_buf.offset > PAGE_SIZE) {
-			slot_buf.page++;
-			slot_buf.offset -= PAGE_SIZE;
-		}
 	}
 	if ((dir == DMA_TO_DEVICE) || (dir == DMA_BIDIRECTIONAL))
 		__sync_single(buffer, dma_addr, size, DMA_TO_DEVICE);
 
 	return dma_addr;
+}
+
+struct phys_addr dma_addr_to_phys_addr(char *dma_addr)
+{
+	int index = (dma_addr - iotlb_virt_start) >> IO_TLB_SHIFT;
+	struct phys_addr buffer = io_tlb_orig_addr[index];
+	buffer.offset += (long)dma_addr & ((1 << IO_TLB_SHIFT) - 1);
+	buffer.page += buffer.offset >> PAGE_SHIFT;
+	buffer.offset &= PAGE_SIZE - 1;
+	return buffer;
 }
 
 /*
@@ -400,7 +408,7 @@ unmap_single(struct device *hwdev, char 
 	unsigned long flags;
 	int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
 	int index = (dma_addr - iotlb_virt_start) >> IO_TLB_SHIFT;
-	struct phys_addr buffer = io_tlb_orig_addr[index];
+	struct phys_addr buffer = dma_addr_to_phys_addr(dma_addr);
 
 	/*
 	 * First, sync the memory before unmapping the entry
@@ -440,8 +448,7 @@ static void
 static void
 sync_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
 {
-	int index = (dma_addr - iotlb_virt_start) >> IO_TLB_SHIFT;
-	struct phys_addr buffer = io_tlb_orig_addr[index];
+	struct phys_addr buffer = dma_addr_to_phys_addr(dma_addr);
 	BUG_ON((dir != DMA_FROM_DEVICE) && (dir != DMA_TO_DEVICE));
 	__sync_single(buffer, dma_addr, size, dir);
 }

[-- Attachment #3: Type: text/plain, Size: 138 bytes --]

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel