On 05/29/2010 02:55 PM, Arnd Bergmann wrote:
On Saturday 29 May 2010, Tom Lyon wrote:
+/*
+ * Structure for DMA mapping of user buffers
+ * vaddr, dmaaddr, and size must all be page aligned
+ * buffer may only be larger than 1 page if (a) there is
+ * an iommu in the system, or (b) buffer is part of a huge page
+ */
+struct vfio_dma_map {
+ __u64 vaddr; /* process virtual addr */
+ __u64 dmaaddr; /* desired and/or returned dma address */
+ __u64 size; /* size in bytes */
+ int rdwr; /* bool: 0 for r/o; 1 for r/w */
+};
Please add a 32 bit padding word at the end of this, otherwise the
size of the data structure is incompatible between 32 x86 applications
and 64 bit kernels.
Might as well call it 'flags' and reserve a bit more space (keeping
64-bit aligned size) for future expansion.
rdwr can be folded into it.
--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html