Hi Matt,
[...]
> +static int i915_ttm_access_memory(struct ttm_buffer_object *bo,
> + unsigned long offset, void *buf,
> + int len, int write)
> +{
> + struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
> + resource_size_t iomap = obj->mm.region->iomap.base -
> + obj->mm.region->region.start;
> + unsigned long page = offset >> PAGE_SHIFT;
> + unsigned long bytes_left = len;
> +
> + /*
> + * TODO: For now just let it fail if the resource is non-mappable,
> + * otherwise we need to perform the memcpy from the gpu here, without
> + * interfering with the object (like moving the entire thing).
> + */
> + if (!i915_ttm_resource_mappable(bo->resource))
> + return -EIO;
> +
> + offset -= page << PAGE_SHIFT;
> + do {
> + unsigned long bytes = min(bytes_left, PAGE_SIZE - offset);
> + void __iomem *ptr;
> + dma_addr_t daddr;
> +
> + daddr = i915_gem_object_get_dma_address(obj, page);
> + ptr = ioremap_wc(iomap + daddr + offset, PAGE_SIZE);
PAGE_SIZE or bytes? We don't know what there is after "bytes".
Andi
> + if (!ptr)
> + return -EIO;
> +
> + if (write)
> + memcpy_toio(ptr, buf, bytes);
> + else
> + memcpy_fromio(buf, ptr, bytes);
> + iounmap(ptr);
> +
> + page++;
> + buf += bytes;
> + bytes_left -= bytes;
> + offset = 0;
> + } while (bytes_left);
> +
> + return len;
> +}
