[PATCH 4/4] drm/prime: document that use the page array is deprecated v3
Christian König
ckoenig.leichtzumerken at gmail.com
Wed Nov 4 13:00:24 UTC 2020
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
v3: rebased on latest changes
Signed-off-by: Christian König <christian.koenig at amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 9 ++-
drivers/gpu/drm/drm_prime.c | 64 +++++++++++++--------
drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 3 +-
drivers/gpu/drm/mediatek/mtk_drm_gem.c | 2 +-
drivers/gpu/drm/msm/msm_gem.c | 2 +-
drivers/gpu/drm/nouveau/nouveau_bo.c | 5 +-
drivers/gpu/drm/omapdrm/omap_gem.c | 3 +-
drivers/gpu/drm/radeon/radeon_ttm.c | 9 ++-
drivers/gpu/drm/vgem/vgem_drv.c | 3 +-
drivers/gpu/drm/xen/xen_drm_front_gem.c | 4 +-
include/drm/drm_prime.h | 7 ++-
11 files changed, 60 insertions(+), 51 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index d6781b479839..b151c28de978 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1036,8 +1036,8 @@ 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;
@@ -1382,9 +1382,8 @@ 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);
return 0;
}
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index a7b61c2d9190..d181a5de101b 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -984,44 +984,58 @@ 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
+ * @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.
+ *
+ * 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 __deprecated drm_prime_sg_to_page_array(struct sg_table *sgt,
+ struct page **pages,
+ int max_entries)
+{
+ struct sg_page_iter page_iter;
+ struct page **p = pages;
+
+ for_each_sgtable_page(sgt, &page_iter, 0) {
+ if (WARN_ON(p - pages >= max_entries))
+ return -1;
+ *p++ = sg_page_iter_page(&page_iter);
+ }
+ 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 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 addresses.
*
- * Drivers can use this in their &drm_driver.gem_prime_import_sg_table
+ * Drivers should use this in their &drm_driver.gem_prime_import_sg_table
* implementation.
*/
-int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,
- dma_addr_t *addrs, int max_entries)
+int drm_prime_sg_to_dma_addr_array(struct sg_table *sgt, dma_addr_t *addrs,
+ int max_entries)
{
struct sg_dma_page_iter dma_iter;
- struct sg_page_iter page_iter;
- struct page **p = pages;
dma_addr_t *a = addrs;
- if (pages) {
- for_each_sgtable_page(sgt, &page_iter, 0) {
- if (WARN_ON(p - pages >= max_entries))
- return -1;
- *p++ = sg_page_iter_page(&page_iter);
- }
- }
- if (addrs) {
- for_each_sgtable_dma_page(sgt, &dma_iter, 0) {
- if (WARN_ON(a - addrs >= max_entries))
- return -1;
- *a++ = sg_page_iter_dma_address(&dma_iter);
- }
+ for_each_sgtable_dma_page(sgt, &dma_iter, 0) {
+ if (WARN_ON(a - addrs >= max_entries))
+ return -1;
+ *a++ = sg_page_iter_dma_address(&dma_iter);
}
-
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/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
index cdd1a6e61564..339854338f7e 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c
@@ -258,7 +258,7 @@ void *mtk_drm_gem_prime_vmap(struct drm_gem_object *obj)
if (!mtk_gem->pages)
goto out;
- drm_prime_sg_to_page_addr_arrays(sgt, mtk_gem->pages, NULL, npages);
+ drm_prime_sg_to_page_array(sgt, mtk_gem->pages, npages);
mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP,
pgprot_writecombine(PAGE_KERNEL));
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 311721ceee50..f995cb02b63d 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -1180,7 +1180,7 @@ 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 c1847cf87952..615f6abbd3a9 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -1317,9 +1317,8 @@ 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);
return 0;
}
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index f063f5a04fb0..3adf23042d9d 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -1323,8 +1323,7 @@ struct drm_gem_object *omap_gem_new_dmabuf(struct drm_device *dev, size_t size,
}
omap_obj->pages = pages;
- ret = drm_prime_sg_to_page_addr_arrays(sgt, pages, NULL,
- npages);
+ ret = drm_prime_sg_to_page_array(sgt, pages, npages);
if (ret) {
omap_gem_free_object(obj);
obj = ERR_PTR(-ENOMEM);
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index f41fcee35f70..750d1bae9f1f 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -494,8 +494,8 @@ 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;
@@ -673,9 +673,8 @@ 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);
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/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c
index 4f34ef34ba60..c937ef4e437e 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 0991a47a1567..54f2c58305d2 100644
--- a/include/drm/drm_prime.h
+++ b/include/drm/drm_prime.h
@@ -105,8 +105,9 @@ 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__ */
--
2.25.1
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