On Tue, 2006-12-12 at 23:47 -0800, Andrew Morton wrote: > On Wed, 13 Dec 2006 03:59:45 GMT > Linux Kernel Mailing List <linux-kernel@vger.kernel.org> wrote: > > > IB: Add DMA mapping functions to allow device drivers to interpose > > > > The QLogic InfiniPath HCAs use programmed I/O instead of HW DMA. > > This patch allows a verbs device driver to interpose on DMA mapping > > function calls in order to avoid relying on bus_to_virt() and > > phys_to_virt() to undo the mappings created by dma_map_single(), > > dma_map_sg(), etc. > > > > Signed-off-by: Ralph Campbell <[EMAIL PROTECTED]> > > Signed-off-by: Roland Dreier <[EMAIL PROTECTED]> > > include/rdma/ib_verbs.h: In function 'ib_dma_alloc_coherent': > include/rdma/ib_verbs.h:1635: warning: passing argument 3 of > 'dma_alloc_coherent' from incompatible pointer type > In file included from drivers/infiniband/hw/mthca/mthca_provider.h:41, > from drivers/infiniband/hw/mthca/mthca_dev.h:53, > from drivers/infiniband/hw/mthca/mthca_main.c:44: > include/rdma/ib_verbs.h: In function 'ib_dma_alloc_coherent': > include/rdma/ib_verbs.h:1635: warning: passing argument 3 of > 'dma_alloc_coherent' from incompatible pointer type > > > That u64 needs to become a dma_addr_t. That means that > ib_dma_mapping_ops.alloc_coherent() and ib_dma_mapping_ops.free_coherent() are > wrong as well. > > > +struct ib_dma_mapping_ops { > > ... > > + void *(*alloc_coherent)(struct ib_device *dev, > > + size_t size, > > + u64 *dma_handle, > > + gfp_t flag); > > + void (*free_coherent)(struct ib_device *dev, > > + size_t size, void *cpu_addr, > > + u64 dma_handle); > > +}; > > I'd have picked this up if it had been in git-infiniband for even a couple > of days. I'm assuming this all got slammed into mainline because of the > merge window thing. > > I cannot find these patches on the kernel mailing list. I cannot find the > pull request anywhere. > > > +static inline u64 ib_dma_map_single(struct ib_device *dev, > > + void *cpu_addr, size_t size, > > + enum dma_data_direction direction) > > no, dma_map_single() returns a dma_addr_t.
ib_dma_map_single() allows the ib_ipath device driver to interpose on IOMMU allocations and not do them by returning the kernel virtual address as the "DMA address". I started with dma_addr_t but it was pointed out to me that sparc64 defines dma_addr_t as u32. This would cause addresses to be truncated. Also, I chose u64 because the return value from ib_dma_*() is stored in the ib_sge.addr field which is u64. My preference would be to change the offending uses of dma_addr_t to u64. Do you have a better solution? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/