On Mon, Oct 19, 2020 at 11:45:05AM +0200, Christian König wrote: > Hi Thomas, > > [SNIP] > > > > +int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map > > > > *map) > > > > +{ > > > > + struct ttm_resource *mem = &bo->mem; > > > > + int ret; > > > > + > > > > + ret = ttm_mem_io_reserve(bo->bdev, mem); > > > > + if (ret) > > > > + return ret; > > > > + > > > > + if (mem->bus.is_iomem) { > > > > + void __iomem *vaddr_iomem; > > > > + unsigned long size = bo->num_pages << PAGE_SHIFT; > > > Please use uint64_t here and make sure to cast bo->num_pages before > > > shifting. > > I thought the rule of thumb is to use u64 in source code. Yet TTM only > > uses uint*_t types. Is there anything special about TTM? > > My last status is that you can use both and my personal preference is to use > the uint*_t types because they are part of a higher level standard.
Yeah the only hard rule is that in uapi headers you need to use the __u64 and similar typedefs, to avoid cluttering the namespace for unrelated stuff in userspace. In the kernel c99 types are perfectly fine, and I think slowly on the rise. -Daniel > > > > We have an unit tests of allocating a 8GB BO and that should work on a > > > 32bit machine as well :) > > > > > > > + > > > > + if (mem->bus.addr) > > > > + vaddr_iomem = (void *)(((u8 *)mem->bus.addr)); > > I after reading the patch again, I realized that this is the > > 'ttm_bo_map_premapped' case and it's missing from _vunmap(). I see two > > options here: ignore this case in _vunmap(), or do an ioremap() > > unconditionally. Which one is preferable? > > ioremap would be very very bad, so we should just do nothing. > > Thanks, > Christian. > > > > > Best regards > > Thomas > > > > > > + else if (mem->placement & TTM_PL_FLAG_WC) > > > I've just nuked the TTM_PL_FLAG_WC flag in drm-misc-next. There is a new > > > mem->bus.caching enum as replacement. > > > > > > > + vaddr_iomem = ioremap_wc(mem->bus.offset, size); > > > > + else > > > > + vaddr_iomem = ioremap(mem->bus.offset, size); > > > > + > > > > + if (!vaddr_iomem) > > > > + return -ENOMEM; > > > > + > > > > + dma_buf_map_set_vaddr_iomem(map, vaddr_iomem); > > > > + > > > > + } else { > > > > + struct ttm_operation_ctx ctx = { > > > > + .interruptible = false, > > > > + .no_wait_gpu = false > > > > + }; > > > > + struct ttm_tt *ttm = bo->ttm; > > > > + pgprot_t prot; > > > > + void *vaddr; > > > > + > > > > + BUG_ON(!ttm); > > > I think we can drop this, populate will just crash badly anyway. > > > > > > > + > > > > + ret = ttm_tt_populate(bo->bdev, ttm, &ctx); > > > > + if (ret) > > > > + return ret; > > > > + > > > > + /* > > > > + * We need to use vmap to get the desired page protection > > > > + * or to make the buffer object look contiguous. > > > > + */ > > > > + prot = ttm_io_prot(mem->placement, PAGE_KERNEL); > > > The calling convention has changed on drm-misc-next as well, but should > > > be trivial to adapt. > > > > > > Regards, > > > Christian. > > > > > > > + vaddr = vmap(ttm->pages, bo->num_pages, 0, prot); > > > > + if (!vaddr) > > > > + return -ENOMEM; > > > > + > > > > + dma_buf_map_set_vaddr(map, vaddr); > > > > + } > > > > + > > > > + return 0; > > > > +} > > > > +EXPORT_SYMBOL(ttm_bo_vmap); > > > > + > > > > +void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map > > > > *map) > > > > +{ > > > > + if (dma_buf_map_is_null(map)) > > > > + return; > > > > + > > > > + if (map->is_iomem) > > > > + iounmap(map->vaddr_iomem); > > > > + else > > > > + vunmap(map->vaddr); > > > > + dma_buf_map_clear(map); > > > > + > > > > + ttm_mem_io_free(bo->bdev, &bo->mem); > > > > +} > > > > +EXPORT_SYMBOL(ttm_bo_vunmap); > > > > + > > > > static int ttm_bo_wait_free_node(struct ttm_buffer_object *bo, > > > > bool dst_use_tt) > > > > { > > > > diff --git a/include/drm/drm_gem_ttm_helper.h > > > > b/include/drm/drm_gem_ttm_helper.h > > > > index 118cef76f84f..7c6d874910b8 100644 > > > > --- a/include/drm/drm_gem_ttm_helper.h > > > > +++ b/include/drm/drm_gem_ttm_helper.h > > > > @@ -10,11 +10,17 @@ > > > > #include <drm/ttm/ttm_bo_api.h> > > > > #include <drm/ttm/ttm_bo_driver.h> > > > > +struct dma_buf_map; > > > > + > > > > #define drm_gem_ttm_of_gem(gem_obj) \ > > > > container_of(gem_obj, struct ttm_buffer_object, base) > > > > void drm_gem_ttm_print_info(struct drm_printer *p, unsigned int > > > > indent, > > > > const struct drm_gem_object *gem); > > > > +int drm_gem_ttm_vmap(struct drm_gem_object *gem, > > > > + struct dma_buf_map *map); > > > > +void drm_gem_ttm_vunmap(struct drm_gem_object *gem, > > > > + struct dma_buf_map *map); > > > > int drm_gem_ttm_mmap(struct drm_gem_object *gem, > > > > struct vm_area_struct *vma); > > > > diff --git a/include/drm/ttm/ttm_bo_api.h > > > > b/include/drm/ttm/ttm_bo_api.h > > > > index 37102e45e496..2c59a785374c 100644 > > > > --- a/include/drm/ttm/ttm_bo_api.h > > > > +++ b/include/drm/ttm/ttm_bo_api.h > > > > @@ -48,6 +48,8 @@ struct ttm_bo_global; > > > > struct ttm_bo_device; > > > > +struct dma_buf_map; > > > > + > > > > struct drm_mm_node; > > > > struct ttm_placement; > > > > @@ -494,6 +496,32 @@ int ttm_bo_kmap(struct ttm_buffer_object *bo, > > > > unsigned long start_page, > > > > */ > > > > void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map); > > > > +/** > > > > + * ttm_bo_vmap > > > > + * > > > > + * @bo: The buffer object. > > > > + * @map: pointer to a struct dma_buf_map representing the map. > > > > + * > > > > + * Sets up a kernel virtual mapping, using ioremap or vmap to the > > > > + * data in the buffer object. The parameter @map returns the virtual > > > > + * address as struct dma_buf_map. Unmap the buffer with > > > > ttm_bo_vunmap(). > > > > + * > > > > + * Returns > > > > + * -ENOMEM: Out of memory. > > > > + * -EINVAL: Invalid range. > > > > + */ > > > > +int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map); > > > > + > > > > +/** > > > > + * ttm_bo_vunmap > > > > + * > > > > + * @bo: The buffer object. > > > > + * @map: Object describing the map to unmap. > > > > + * > > > > + * Unmaps a kernel map set up by ttm_bo_vmap(). > > > > + */ > > > > +void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map > > > > *map); > > > > + > > > > /** > > > > * ttm_bo_mmap_obj - mmap memory backed by a ttm buffer object. > > > > * > > > > diff --git a/include/linux/dma-buf-map.h b/include/linux/dma-buf-map.h > > > > index fd1aba545fdf..2e8bbecb5091 100644 > > > > --- a/include/linux/dma-buf-map.h > > > > +++ b/include/linux/dma-buf-map.h > > > > @@ -45,6 +45,12 @@ > > > > * > > > > * dma_buf_map_set_vaddr(&map. 0xdeadbeaf); > > > > * > > > > + * To set an address in I/O memory, use dma_buf_map_set_vaddr_iomem(). > > > > + * > > > > + * .. code-block:: c > > > > + * > > > > + * dma_buf_map_set_vaddr_iomem(&map. 0xdeadbeaf); > > > > + * > > > > * Test if a mapping is valid with either dma_buf_map_is_set() or > > > > * dma_buf_map_is_null(). > > > > * > > > > @@ -118,6 +124,20 @@ static inline void dma_buf_map_set_vaddr(struct > > > > dma_buf_map *map, void *vaddr) > > > > map->is_iomem = false; > > > > } > > > > +/** > > > > + * dma_buf_map_set_vaddr_iomem - Sets a dma-buf mapping structure to > > > > an address in I/O memory > > > > + * @map: The dma-buf mapping structure > > > > + * @vaddr_iomem: An I/O-memory address > > > > + * > > > > + * Sets the address and the I/O-memory flag. > > > > + */ > > > > +static inline void dma_buf_map_set_vaddr_iomem(struct dma_buf_map *map, > > > > + void __iomem *vaddr_iomem) > > > > +{ > > > > + map->vaddr_iomem = vaddr_iomem; > > > > + map->is_iomem = true; > > > > +} > > > > + > > > > /** > > > > * dma_buf_map_is_equal - Compares two dma-buf mapping structures > > > > for equality > > > > * @lhs: The dma-buf mapping structure > > > _______________________________________________ > > > dri-devel mailing list > > > dri-de...@lists.freedesktop.org > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fdri-devel&data=04%7C01%7Cchristian.koenig%40amd.com%7C07bc68af3c6440b5be8d08d8740e9b32%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637386953433558595%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=RlGCmjzyZERvqfnl4kA1bEHez5bkLf3F9OlKi2ybDAM%3D&reserved=0 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch