fix cciss DMA unmap brokenness

PATCH New Alex Williamson 1 participant 1 message Aug 17, 2005 Block layer

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Alex Williamson

author

2005-08-17 19:16 UTC #0 lore raw

PATCH 1/1 fix cciss DMA unmap brokenness

The CCISS driver seems to loose track of DMA mappings created by it's
fill_cmd() routine. Neither callers of this routine are extracting the DMA address created in order to do the unmap. Instead, they simply try to unmap 0x0. It's easy to see this problem on an x86_64 system when using the "swiotlb=force" boot option. In this case, the driver is leaking resources of the swiotlb and not causing a sync of the bounce buffer. Thanks

Signed-off-by Alex Williamson <[email protected]>

drivers/block/cciss.c +6 -2

diff -r b9c8e9fdd6b2 drivers/block/cciss.c
@@ -1420,8 +1420,10 @@
 		}
 	}	
 	/* unlock the buffers from DMA */
+	buff_dma_handle.val32.lower = c->SG[0].Addr.lower;
+	buff_dma_handle.val32.upper = c->SG[0].Addr.upper;
 	pci_unmap_single( h->pdev, (dma_addr_t) buff_dma_handle.val,
-			size, PCI_DMA_BIDIRECTIONAL);
+			c->SG[0].Len, PCI_DMA_BIDIRECTIONAL);
 	cmd_free(h, c, 0);
         return(return_status);

@@ -1860,8 +1862,10 @@
 		
 cleanup1:	
 	/* unlock the data buffer from DMA */
+	buff_dma_handle.val32.lower = c->SG[0].Addr.lower;
+	buff_dma_handle.val32.upper = c->SG[0].Addr.upper;
 	pci_unmap_single(info_p->pdev, (dma_addr_t) buff_dma_handle.val,
-				size, PCI_DMA_BIDIRECTIONAL);
+				c->SG[0].Len, PCI_DMA_BIDIRECTIONAL);
 	cmd_free(info_p, c, 1);
 	return (status);
 }