We have reoccurring requests on this so better document that this approach doesn't work and dma_buf_mmap() needs to be used instead.
v2: split it into two functions
Signed-off-by: Christian König christian.koenig@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 9 ++- drivers/gpu/drm/drm_prime.c | 67 +++++++++++++++------ drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 3 +- drivers/gpu/drm/msm/msm_gem.c | 2 +- drivers/gpu/drm/nouveau/nouveau_bo.c | 5 +- drivers/gpu/drm/radeon/radeon_ttm.c | 9 ++- drivers/gpu/drm/vgem/vgem_drv.c | 3 +- drivers/gpu/drm/vkms/vkms_gem.c | 2 +- drivers/gpu/drm/xen/xen_drm_front_gem.c | 4 +- include/drm/drm_prime.h | 7 ++- 10 files changed, 69 insertions(+), 42 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index ac463e706b19..6a65490de391 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -1011,8 +1011,8 @@ static int amdgpu_ttm_tt_pin_userptr(struct ttm_bo_device *bdev, goto release_sg;
/* convert SG to linear array of pages and dma addresses */ - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, gtt->ttm.dma_address, - ttm->num_pages); + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address, + ttm->num_pages);
return 0;
@@ -1345,9 +1345,8 @@ static int amdgpu_ttm_tt_populate(struct ttm_bo_device *bdev, ttm->sg = sgt; }
- drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, - gtt->ttm.dma_address, - ttm->num_pages); + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address, + ttm->num_pages); ttm_tt_set_populated(ttm); return 0; } diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 4910c446db83..8b750c074494 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -954,27 +954,25 @@ struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, EXPORT_SYMBOL(drm_gem_prime_import);
/** - * drm_prime_sg_to_page_addr_arrays - convert an sg table into a page array + * drm_prime_sg_to_page_array - convert an sg table into a page array * @sgt: scatter-gather table to convert - * @pages: optional array of page pointers to store the page array in - * @addrs: optional array to store the dma bus address of each page - * @max_entries: size of both the passed-in arrays + * @pages: array of page pointers to store the pages in + * @max_entries: size of the passed-in array * - * Exports an sg table into an array of pages and addresses. This is currently - * required by the TTM driver in order to do correct fault handling. + * Exports an sg table into an array of pages. * - * Drivers can use this in their &drm_driver.gem_prime_import_sg_table - * implementation. + * This function is deprecated and strongly discouraged to be used. + * The page array is only useful for page faults and those can corrupt fields + * in the struct page if they are not handled by the exporting driver. */ -int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, - dma_addr_t *addrs, int max_entries) +int __deprecated drm_prime_sg_to_page_array(struct sg_table *sgt, + struct page **pages, + int max_entries) { unsigned count; struct scatterlist *sg; struct page *page; u32 page_len, page_index; - dma_addr_t addr; - u32 dma_len, dma_index;
/* * Scatterlist elements contains both pages and DMA addresses, but @@ -984,14 +982,11 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, * described by the sg_dma_address(sg). */ page_index = 0; - dma_index = 0; for_each_sg(sgt->sgl, sg, sgt->nents, count) { page_len = sg->length; page = sg_page(sg); - dma_len = sg_dma_len(sg); - addr = sg_dma_address(sg);
- while (pages && page_len > 0) { + while (page_len > 0) { if (WARN_ON(page_index >= max_entries)) return -1; pages[page_index] = page; @@ -999,7 +994,43 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, page_len -= PAGE_SIZE; page_index++; } - while (addrs && dma_len > 0) { + } + return 0; +} +EXPORT_SYMBOL(drm_prime_sg_to_page_array); + +/** + * drm_prime_sg_to_dma_addr_array - convert an sg table into a dma addr array + * @sgt: scatter-gather table to convert + * @addrs: array to store the dma bus address of each page + * @max_entries: size of both the passed-in arrays + * + * Exports an sg table into an array of addresses. + * + * Drivers should use this in their &drm_driver.gem_prime_import_sg_table + * implementation. + */ +int drm_prime_sg_to_dma_addr_array(struct sg_table *sgt, dma_addr_t *addrs, + int max_entries) +{ + struct scatterlist *sg; + u32 dma_len, dma_index; + dma_addr_t addr; + unsigned count; + + /* + * Scatterlist elements contains both pages and DMA addresses, but + * one shoud not assume 1:1 relation between them. The sg->length is + * the size of the physical memory chunk described by the sg->page, + * while sg_dma_len(sg) is the size of the DMA (IO virtual) chunk + * described by the sg_dma_address(sg). + */ + dma_index = 0; + for_each_sg(sgt->sgl, sg, sgt->nents, count) { + dma_len = sg_dma_len(sg); + addr = sg_dma_address(sg); + + while (dma_len > 0) { if (WARN_ON(dma_index >= max_entries)) return -1; addrs[dma_index] = addr; @@ -1010,7 +1041,7 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, } return 0; } -EXPORT_SYMBOL(drm_prime_sg_to_page_addr_arrays); +EXPORT_SYMBOL(drm_prime_sg_to_dma_addr_array);
/** * drm_prime_gem_destroy - helper to clean up a PRIME-imported GEM object diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c index 135fbff6fecf..8c04b8e8054c 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c @@ -133,8 +133,7 @@ struct drm_gem_object *etnaviv_gem_prime_import_sg_table(struct drm_device *dev, goto fail; }
- ret = drm_prime_sg_to_page_addr_arrays(sgt, etnaviv_obj->pages, - NULL, npages); + ret = drm_prime_sg_to_page_array(sgt, etnaviv_obj->pages, npages); if (ret) goto fail;
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index a71f42870d5e..616b87641740 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -1174,7 +1174,7 @@ struct drm_gem_object *msm_gem_import(struct drm_device *dev, goto fail; }
- ret = drm_prime_sg_to_page_addr_arrays(sgt, msm_obj->pages, NULL, npages); + ret = drm_prime_sg_to_page_array(sgt, msm_obj->pages, npages); if (ret) { mutex_unlock(&msm_obj->lock); goto fail; diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c index e378bb491688..835edd74ef59 100644 --- a/drivers/gpu/drm/nouveau/nouveau_bo.c +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c @@ -1299,9 +1299,8 @@ nouveau_ttm_tt_populate(struct ttm_bo_device *bdev, return 0;
if (slave && ttm->sg) { - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, - ttm_dma->dma_address, - ttm->num_pages); + drm_prime_sg_to_dma_addr_array(ttm->sg, ttm_dma->dma_address, + ttm->num_pages); ttm_tt_set_populated(ttm); return 0; } diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c index 4b92cdbcd29b..7997e4564576 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -474,8 +474,8 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_bo_device *bdev, struct ttm_tt * if (r) goto release_sg;
- drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, gtt->ttm.dma_address, - ttm->num_pages); + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address, + ttm->num_pages);
return 0;
@@ -642,9 +642,8 @@ static int radeon_ttm_tt_populate(struct ttm_bo_device *bdev, }
if (slave && ttm->sg) { - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, - gtt->ttm.dma_address, - ttm->num_pages); + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address, + ttm->num_pages); ttm_tt_set_populated(ttm); return 0; } diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index ea0eecae5153..e505e5a291b3 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -356,8 +356,7 @@ static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev, }
obj->pages_pin_count++; /* perma-pinned */ - drm_prime_sg_to_page_addr_arrays(obj->table, obj->pages, NULL, - npages); + drm_prime_sg_to_page_array(obj->table, obj->pages, npages); return &obj->base; }
diff --git a/drivers/gpu/drm/vkms/vkms_gem.c b/drivers/gpu/drm/vkms/vkms_gem.c index 19a0e260a4df..a2ff21f47101 100644 --- a/drivers/gpu/drm/vkms/vkms_gem.c +++ b/drivers/gpu/drm/vkms/vkms_gem.c @@ -256,6 +256,6 @@ vkms_prime_import_sg_table(struct drm_device *dev, return ERR_PTR(-ENOMEM); }
- drm_prime_sg_to_page_addr_arrays(sg, obj->pages, NULL, npages); + drm_prime_sg_to_page_array(sg, obj->pages, npages); return &obj->gem; } diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c index f3830a0d1808..f4150ddfc5e2 100644 --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -220,8 +220,8 @@ xen_drm_front_gem_import_sg_table(struct drm_device *dev,
xen_obj->sgt_imported = sgt;
- ret = drm_prime_sg_to_page_addr_arrays(sgt, xen_obj->pages, - NULL, xen_obj->num_pages); + ret = drm_prime_sg_to_page_array(sgt, xen_obj->pages, + xen_obj->num_pages); if (ret < 0) return ERR_PTR(ret);
diff --git a/include/drm/drm_prime.h b/include/drm/drm_prime.h index 093f760cc131..4bda9ab3a3bb 100644 --- a/include/drm/drm_prime.h +++ b/include/drm/drm_prime.h @@ -103,8 +103,9 @@ struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev,
void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg);
-int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, - dma_addr_t *addrs, int max_pages); - +int drm_prime_sg_to_page_array(struct sg_table *sgt, struct page **pages, + int max_pages); +int drm_prime_sg_to_dma_addr_array(struct sg_table *sgt, dma_addr_t *addrs, + int max_pages);
#endif /* __DRM_PRIME_H__ */