Re: [PATCH v3 3/7] drm/gem: Use struct dma_buf_map in GEM vmap ops and convert GEM backends

Daniel Vetter
2020-10-02T13:02:59Z

On Tue, Sep 29, 2020 at 05:14:33PM +0200, Thomas Zimmermann wrote:
> This patch replaces the vmap/vunmap's use of raw pointers in GEM object
> functions with instances of struct dma_buf_map. GEM backends are
> converted as well.
>
> For most GEM backends, this simply change the returned type. GEM VRAM
> helpers are also updated to indicate whether the returned framebuffer
> address is in system or I/O memory.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c | 14 ++--
> drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h | 4 +-
> drivers/gpu/drm/ast/ast_cursor.c | 29 +++----
> drivers/gpu/drm/ast/ast_drv.h | 7 +-
> drivers/gpu/drm/drm_gem.c | 22 ++---
> drivers/gpu/drm/drm_gem_cma_helper.c | 14 ++--
> drivers/gpu/drm/drm_gem_shmem_helper.c | 48 ++++++-----
> drivers/gpu/drm/drm_gem_vram_helper.c | 90 +++++++++++----------
> drivers/gpu/drm/etnaviv/etnaviv_drv.h | 4 +-
> drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 11 ++-
> drivers/gpu/drm/exynos/exynos_drm_gem.c | 6 +-
> drivers/gpu/drm/exynos/exynos_drm_gem.h | 4 +-
> drivers/gpu/drm/lima/lima_gem.c | 6 +-
> drivers/gpu/drm/lima/lima_sched.c | 11 ++-
> drivers/gpu/drm/mgag200/mgag200_mode.c | 12 +--
> drivers/gpu/drm/nouveau/nouveau_gem.h | 4 +-
> drivers/gpu/drm/nouveau/nouveau_prime.c | 9 ++-
> drivers/gpu/drm/panfrost/panfrost_perfcnt.c | 14 ++--
> drivers/gpu/drm/qxl/qxl_display.c | 13 +--
> drivers/gpu/drm/qxl/qxl_draw.c | 16 ++--
> drivers/gpu/drm/qxl/qxl_drv.h | 8 +-
> drivers/gpu/drm/qxl/qxl_object.c | 23 +++---
> drivers/gpu/drm/qxl/qxl_object.h | 2 +-
> drivers/gpu/drm/qxl/qxl_prime.c | 12 +--
> drivers/gpu/drm/radeon/radeon_gem.c | 4 +-
> drivers/gpu/drm/radeon/radeon_prime.c | 9 ++-
> drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 22 +++--
> drivers/gpu/drm/rockchip/rockchip_drm_gem.h | 4 +-
> drivers/gpu/drm/tiny/cirrus.c | 10 ++-
> drivers/gpu/drm/tiny/gm12u320.c | 10 ++-
> drivers/gpu/drm/udl/udl_modeset.c | 8 +-
> drivers/gpu/drm/vboxvideo/vbox_mode.c | 11 ++-
> drivers/gpu/drm/vc4/vc4_bo.c | 6 +-
> drivers/gpu/drm/vc4/vc4_drv.h | 2 +-
> drivers/gpu/drm/vgem/vgem_drv.c | 16 ++--
> drivers/gpu/drm/xen/xen_drm_front_gem.c | 18 +++--
> drivers/gpu/drm/xen/xen_drm_front_gem.h | 6 +-
> include/drm/drm_gem.h | 5 +-
> include/drm/drm_gem_cma_helper.h | 4 +-
> include/drm/drm_gem_shmem_helper.h | 4 +-
> include/drm/drm_gem_vram_helper.h | 4 +-
> 41 files changed, 304 insertions(+), 222 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
> index 5b465ab774d1..de7d0cfe1b93 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
> @@ -44,13 +44,14 @@
> /**
> * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation
> * @obj: GEM BO
> + * @map: The virtual address of the mapping.
> *
> * Sets up an in-kernel virtual mapping of the BO's memory.
> *
> * Returns:
> - * The virtual address of the mapping or an error pointer.
> + * 0 on success, or a negative errno code otherwise.
> */
> -void *amdgpu_gem_prime_vmap(struct drm_gem_object *obj)
> +int amdgpu_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
> int ret;
> @@ -58,19 +59,20 @@ void *amdgpu_gem_prime_vmap(struct drm_gem_object *obj)
> ret = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages,
> &bo->dma_buf_vmap);
> if (ret)
> - return ERR_PTR(ret);
> + return ret;
> + ttm_kmap_obj_to_dma_buf_map(&bo->dma_buf_vmap, map);

I guess with the ttm_bo_vmap idea all the ttm changes here will look a bit
different.

>
> - return bo->dma_buf_vmap.virtual;
> + return 0;
> }
>
> /**
> * amdgpu_gem_prime_vunmap - &dma_buf_ops.vunmap implementation
> * @obj: GEM BO
> - * @vaddr: Virtual address (unused)
> + * @map: Virtual address (unused)
> *
> * Tears down the in-kernel virtual mapping of the BO's memory.
> */
> -void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h
> index 2c5c84a06bb9..622642793064 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h
> @@ -31,8 +31,8 @@ struct drm_gem_object *amdgpu_gem_prime_import(struct drm_device *dev,
> struct dma_buf *dma_buf);
> bool amdgpu_dmabuf_is_xgmi_accessible(struct amdgpu_device *adev,
> struct amdgpu_bo *bo);
> -void *amdgpu_gem_prime_vmap(struct drm_gem_object *obj);
> -void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int amdgpu_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void amdgpu_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> int amdgpu_gem_prime_mmap(struct drm_gem_object *obj,
> struct vm_area_struct *vma);
>
> diff --git a/drivers/gpu/drm/ast/ast_cursor.c b/drivers/gpu/drm/ast/ast_cursor.c
> index e0f4613918ad..459a3774e4e1 100644
> --- a/drivers/gpu/drm/ast/ast_cursor.c
> +++ b/drivers/gpu/drm/ast/ast_cursor.c
> @@ -39,7 +39,7 @@ static void ast_cursor_fini(struct ast_private *ast)
>
> for (i = 0; i < ARRAY_SIZE(ast->cursor.gbo); ++i) {
> gbo = ast->cursor.gbo[i];
> - drm_gem_vram_vunmap(gbo, ast->cursor.vaddr[i]);
> + drm_gem_vram_vunmap(gbo, &ast->cursor.map[i]);
> drm_gem_vram_unpin(gbo);
> drm_gem_vram_put(gbo);
> }
> @@ -60,7 +60,7 @@ int ast_cursor_init(struct ast_private *ast)
> struct drm_device *dev = &ast->base;
> size_t size, i;
> struct drm_gem_vram_object *gbo;
> - void __iomem *vaddr;
> + struct dma_buf_map map;
> int ret;
>
> size = roundup(AST_HWC_SIZE + AST_HWC_SIGNATURE_SIZE, PAGE_SIZE);
> @@ -77,16 +77,15 @@ int ast_cursor_init(struct ast_private *ast)
> drm_gem_vram_put(gbo);
> goto err_drm_gem_vram_put;
> }
> - vaddr = drm_gem_vram_vmap(gbo);
> - if (IS_ERR(vaddr)) {
> - ret = PTR_ERR(vaddr);
> + ret = drm_gem_vram_vmap(gbo, &map);
> + if (ret) {
> drm_gem_vram_unpin(gbo);
> drm_gem_vram_put(gbo);
> goto err_drm_gem_vram_put;
> }
>
> ast->cursor.gbo[i] = gbo;
> - ast->cursor.vaddr[i] = vaddr;
> + ast->cursor.map[i] = map;
> }
>
> return drmm_add_action_or_reset(dev, ast_cursor_release, NULL);
> @@ -95,7 +94,7 @@ int ast_cursor_init(struct ast_private *ast)
> while (i) {
> --i;
> gbo = ast->cursor.gbo[i];
> - drm_gem_vram_vunmap(gbo, ast->cursor.vaddr[i]);
> + drm_gem_vram_vunmap(gbo, &ast->cursor.map[i]);
> drm_gem_vram_unpin(gbo);
> drm_gem_vram_put(gbo);
> }
> @@ -170,8 +169,8 @@ int ast_cursor_blit(struct ast_private *ast, struct drm_framebuffer *fb)
> {
> struct drm_device *dev = &ast->base;
> struct drm_gem_vram_object *gbo;
> + struct dma_buf_map map;
> int ret;
> - void *src;
> void __iomem *dst;
>
> if (drm_WARN_ON_ONCE(dev, fb->width > AST_MAX_HWC_WIDTH) ||
> @@ -183,18 +182,16 @@ int ast_cursor_blit(struct ast_private *ast, struct drm_framebuffer *fb)
> ret = drm_gem_vram_pin(gbo, 0);
> if (ret)
> return ret;
> - src = drm_gem_vram_vmap(gbo);
> - if (IS_ERR(src)) {
> - ret = PTR_ERR(src);
> + ret = drm_gem_vram_vmap(gbo, &map);
> + if (ret)
> goto err_drm_gem_vram_unpin;
> - }
>
> - dst = ast->cursor.vaddr[ast->cursor.next_index];
> + dst = ast->cursor.map[ast->cursor.next_index].vaddr_iomem;
>
> /* do data transfer to cursor BO */
> - update_cursor_image(dst, src, fb->width, fb->height);
> + update_cursor_image(dst, map.vaddr, fb->width, fb->height);

I don't think digging around in the pointer is a good idea, imo this
should get a

/* TODO: Use mapping abstraction properly */

or similar. Same for all the other usage for map.vaddr added to drivers
below (the stuff in helpers that the next patches will change again I
think you can leave as-is, it'll go away).

I'm also wondering whether we should prefix all members of struct
dma_buf_map with _ to make it clear they shouldn't be touched, so
map._vaddr and map._is_iomem.

Also todo.rst entry for all these, there's a lot from looking throught
this patch.

>
> - drm_gem_vram_vunmap(gbo, src);
> + drm_gem_vram_vunmap(gbo, &map);
> drm_gem_vram_unpin(gbo);
>
> return 0;
> @@ -257,7 +254,7 @@ void ast_cursor_show(struct ast_private *ast, int x, int y,
> u8 __iomem *sig;
> u8 jreg;
>
> - dst = ast->cursor.vaddr[ast->cursor.next_index];
> + dst = ast->cursor.map[ast->cursor.next_index].vaddr;
>
> sig = dst + AST_HWC_SIZE;
> writel(x, sig + AST_HWC_SIGNATURE_X);
> diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
> index 467049ca8430..f963141dd851 100644
> --- a/drivers/gpu/drm/ast/ast_drv.h
> +++ b/drivers/gpu/drm/ast/ast_drv.h
> @@ -28,10 +28,11 @@
> #ifndef __AST_DRV_H__
> #define __AST_DRV_H__
>
> -#include <linux/types.h>
> -#include <linux/io.h>
> +#include <linux/dma-buf-map.h>
> #include <linux/i2c.h>
> #include <linux/i2c-algo-bit.h>
> +#include <linux/io.h>
> +#include <linux/types.h>
>
> #include <drm/drm_connector.h>
> #include <drm/drm_crtc.h>
> @@ -131,7 +132,7 @@ struct ast_private {
>
> struct {
> struct drm_gem_vram_object *gbo[AST_DEFAULT_HWC_NUM];
> - void __iomem *vaddr[AST_DEFAULT_HWC_NUM];
> + struct dma_buf_map map[AST_DEFAULT_HWC_NUM];
> unsigned int next_index;
> } cursor;
>
> diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
> index 1da67d34e55d..0c4a66dea5c2 100644
> --- a/drivers/gpu/drm/drm_gem.c
> +++ b/drivers/gpu/drm/drm_gem.c
> @@ -1207,26 +1207,30 @@ void drm_gem_unpin(struct drm_gem_object *obj)
>
> void *drm_gem_vmap(struct drm_gem_object *obj)
> {
> - void *vaddr;
> + struct dma_buf_map map;
> + int ret;
>
> - if (obj->funcs->vmap)
> - vaddr = obj->funcs->vmap(obj);
> - else
> - vaddr = ERR_PTR(-EOPNOTSUPP);
> + if (!obj->funcs->vmap) {
> + return ERR_PTR(-EOPNOTSUPP);
>
> - if (!vaddr)
> - vaddr = ERR_PTR(-ENOMEM);
> + ret = obj->funcs->vmap(obj, &map);
> + if (ret)
> + return ERR_PTR(ret);
> + else if (dma_buf_map_is_null(&map))
> + return ERR_PTR(-ENOMEM);
>
> - return vaddr;
> + return map.vaddr;
> }
>
> void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr)
> {
> + struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(vaddr);
> +
> if (!vaddr)
> return;
>
> if (obj->funcs->vunmap)
> - obj->funcs->vunmap(obj, vaddr);
> + obj->funcs->vunmap(obj, &map);
> }
>
> /**
> diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
> index 2165633c9b9e..e87cd36518d3 100644
> --- a/drivers/gpu/drm/drm_gem_cma_helper.c
> +++ b/drivers/gpu/drm/drm_gem_cma_helper.c
> @@ -519,6 +519,8 @@ EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
> * drm_gem_cma_prime_vmap - map a CMA GEM object into the kernel's virtual
> * address space
> * @obj: GEM object
> + * @map: Returns the kernel virtual address of the CMA GEM object's backing
> + * store.
> *
> * This function maps a buffer exported via DRM PRIME into the kernel's
> * virtual address space. Since the CMA buffers are already mapped into the
> @@ -527,13 +529,15 @@ EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
> * driver's &drm_gem_object_funcs.vmap callback.
> *
> * Returns:
> - * The kernel virtual address of the CMA GEM object's backing store.
> + * 0 on success, or a negative error code otherwise.
> */
> -void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj)
> +int drm_gem_cma_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
>
> - return cma_obj->vaddr;
> + dma_buf_map_set_vaddr(map, cma_obj->vaddr);
> +
> + return 0;
> }
> EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap);
>
> @@ -541,14 +545,14 @@ EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap);
> * drm_gem_cma_prime_vunmap - unmap a CMA GEM object from the kernel's virtual
> * address space
> * @obj: GEM object
> - * @vaddr: kernel virtual address where the CMA GEM object was mapped
> + * @map: Kernel virtual address where the CMA GEM object was mapped
> *
> * This function removes a buffer exported via DRM PRIME from the kernel's
> * virtual address space. This is a no-op because CMA buffers cannot be
> * unmapped from kernel space. Drivers using the CMA helpers should set this
> * as their &drm_gem_object_funcs.vunmap callback.
> */
> -void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> /* Nothing to do */
> }
> diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c
> index fb11df7aced5..5553f58f68f3 100644
> --- a/drivers/gpu/drm/drm_gem_shmem_helper.c
> +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c
> @@ -258,19 +258,25 @@ void drm_gem_shmem_unpin(struct drm_gem_object *obj)
> }
> EXPORT_SYMBOL(drm_gem_shmem_unpin);
>
> -static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem)
> +static int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, struct dma_buf_map *map)
> {
> struct drm_gem_object *obj = &shmem->base;
> - struct dma_buf_map map;
> int ret = 0;
>
> - if (shmem->vmap_use_count++ > 0)
> - return shmem->vaddr;
> + if (shmem->vmap_use_count++ > 0) {
> + dma_buf_map_set_vaddr(map, shmem->vaddr);
> + return 0;
> + }
>
> if (obj->import_attach) {
> - ret = dma_buf_vmap(obj->import_attach->dmabuf, &map);
> - if (!ret)
> - shmem->vaddr = map.vaddr;
> + ret = dma_buf_vmap(obj->import_attach->dmabuf, map);
> + if (!ret) {
> + if (WARN_ON(map->is_iomem)) {
> + ret = -EIO;
> + goto err_put_pages;
> + }
> + shmem->vaddr = map->vaddr;
> + }
> } else {
> pgprot_t prot = PAGE_KERNEL;
>
> @@ -284,6 +290,8 @@ static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem)
> VM_MAP, prot);
> if (!shmem->vaddr)
> ret = -ENOMEM;
> + else
> + dma_buf_map_set_vaddr(map, shmem->vaddr);
> }
>
> if (ret) {
> @@ -291,7 +299,7 @@ static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem)
> goto err_put_pages;
> }
>
> - return shmem->vaddr;
> + return 0;
>
> err_put_pages:
> if (!obj->import_attach)
> @@ -299,12 +307,14 @@ static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem)
> err_zero_use:
> shmem->vmap_use_count = 0;
>
> - return ERR_PTR(ret);
> + return ret;
> }
>
> /*
> * drm_gem_shmem_vmap - Create a virtual mapping for a shmem GEM object
> * @shmem: shmem GEM object
> + * @map: Returns the kernel virtual address of the SHMEM GEM object's backing
> + * store.
> *
> * This function makes sure that a contiguous kernel virtual address mapping
> * exists for the buffer backing the shmem GEM object.
> @@ -318,26 +328,25 @@ static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem)
> * Returns:
> * 0 on success or a negative error code on failure.
> */
> -void *drm_gem_shmem_vmap(struct drm_gem_object *obj)
> +int drm_gem_shmem_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
> - void *vaddr;
> int ret;
>
> ret = mutex_lock_interruptible(&shmem->vmap_lock);
> if (ret)
> - return ERR_PTR(ret);
> - vaddr = drm_gem_shmem_vmap_locked(shmem);
> + return ret;
> + ret = drm_gem_shmem_vmap_locked(shmem, map);
> mutex_unlock(&shmem->vmap_lock);
>
> - return vaddr;
> + return ret;
> }
> EXPORT_SYMBOL(drm_gem_shmem_vmap);
>
> -static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem)
> +static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
> + struct dma_buf_map *map)
> {
> struct drm_gem_object *obj = &shmem->base;
> - struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(shmem->vaddr);
>
> if (WARN_ON_ONCE(!shmem->vmap_use_count))
> return;
> @@ -346,7 +355,7 @@ static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem)
> return;
>
> if (obj->import_attach)
> - dma_buf_vunmap(obj->import_attach->dmabuf, &map);
> + dma_buf_vunmap(obj->import_attach->dmabuf, map);
> else
> vunmap(shmem->vaddr);
>
> @@ -357,6 +366,7 @@ static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem)
> /*
> * drm_gem_shmem_vunmap - Unmap a virtual mapping fo a shmem GEM object
> * @shmem: shmem GEM object
> + * @map: Kernel virtual address where the SHMEM GEM object was mapped
> *
> * This function cleans up a kernel virtual address mapping acquired by
> * drm_gem_shmem_vmap(). The mapping is only removed when the use count drops to
> @@ -366,12 +376,12 @@ static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem)
> * also be called by drivers directly, in which case it will hide the
> * differences between dma-buf imported and natively allocated objects.
> */
> -void drm_gem_shmem_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void drm_gem_shmem_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
>
> mutex_lock(&shmem->vmap_lock);
> - drm_gem_shmem_vunmap_locked(shmem);
> + drm_gem_shmem_vunmap_locked(shmem, map);
> mutex_unlock(&shmem->vmap_lock);
> }
> EXPORT_SYMBOL(drm_gem_shmem_vunmap);
> diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
> index 256b346664f2..6a5b932e0d06 100644
> --- a/drivers/gpu/drm/drm_gem_vram_helper.c
> +++ b/drivers/gpu/drm/drm_gem_vram_helper.c
> @@ -1,5 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0-or-later
>
> +#include <linux/dma-buf-map.h>
> #include <linux/module.h>
>
> #include <drm/drm_debugfs.h>
> @@ -382,11 +383,11 @@ int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo)
> }
> EXPORT_SYMBOL(drm_gem_vram_unpin);
>
> -static void *drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo)
> +static int drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo,
> + struct dma_buf_map *map)
> {
> int ret;
> struct ttm_bo_kmap_obj *kmap = &gbo->kmap;
> - bool is_iomem;
>
> if (gbo->kmap_use_count > 0)
> goto out;
> @@ -396,17 +397,30 @@ static void *drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo)
>
> ret = ttm_bo_kmap(&gbo->bo, 0, gbo->bo.num_pages, kmap);
> if (ret)
> - return ERR_PTR(ret);
> + return ret;
>
> out:
> - if (!kmap->virtual)
> - return NULL; /* not mapped; don't increment ref */
> + if (!kmap->virtual) {
> + dma_buf_map_clear(map);
> + return 0; /* not mapped; don't increment ref */
> + }
> ++gbo->kmap_use_count;
> - return ttm_kmap_obj_virtual(kmap, &is_iomem);
> + ttm_kmap_obj_to_dma_buf_map(kmap, map);
> + return 0;
> }
>
> -static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo)
> +static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo,
> + struct dma_buf_map *map)
> {
> + struct drm_device *dev = gbo->bo.base.dev;
> + struct ttm_bo_kmap_obj *kmap = &gbo->kmap;
> + struct dma_buf_map kmap_map;
> +
> + ttm_kmap_obj_to_dma_buf_map(kmap, &kmap_map);
> +
> + if (drm_WARN_ON_ONCE(dev, !dma_buf_map_is_equal(&kmap_map, map)))
> + return; /* BUG: map not mapped from this BO */
> +
> if (WARN_ON_ONCE(!gbo->kmap_use_count))
> return;
> if (--gbo->kmap_use_count > 0)
> @@ -423,7 +437,9 @@ static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo)
> /**
> * drm_gem_vram_vmap() - Pins and maps a GEM VRAM object into kernel address
> * space
> - * @gbo: The GEM VRAM object to map
> + * @gbo: The GEM VRAM object to map
> + * @map: Returns the kernel virtual address of the VRAM GEM object's backing
> + * store.
> *
> * The vmap function pins a GEM VRAM object to its current location, either
> * system or video memory, and maps its buffer into kernel address space.
> @@ -432,48 +448,44 @@ static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo)
> * unmap and unpin the GEM VRAM object.
> *
> * Returns:
> - * The buffer's virtual address on success, or
> - * an ERR_PTR()-encoded error code otherwise.
> + * 0 on success, or a negative error code otherwise.
> */
> -void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo)
> +int drm_gem_vram_vmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map)
> {
> int ret;
> - void *base;
>
> ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
> if (ret)
> - return ERR_PTR(ret);
> + return ret;
>
> ret = drm_gem_vram_pin_locked(gbo, 0);
> if (ret)
> goto err_ttm_bo_unreserve;
> - base = drm_gem_vram_kmap_locked(gbo);
> - if (IS_ERR(base)) {
> - ret = PTR_ERR(base);
> + ret = drm_gem_vram_kmap_locked(gbo, map);
> + if (ret)
> goto err_drm_gem_vram_unpin_locked;
> - }
>
> ttm_bo_unreserve(&gbo->bo);
>
> - return base;
> + return 0;
>
> err_drm_gem_vram_unpin_locked:
> drm_gem_vram_unpin_locked(gbo);
> err_ttm_bo_unreserve:
> ttm_bo_unreserve(&gbo->bo);
> - return ERR_PTR(ret);
> + return ret;
> }
> EXPORT_SYMBOL(drm_gem_vram_vmap);
>
> /**
> * drm_gem_vram_vunmap() - Unmaps and unpins a GEM VRAM object
> - * @gbo: The GEM VRAM object to unmap
> - * @vaddr: The mapping's base address as returned by drm_gem_vram_vmap()
> + * @gbo: The GEM VRAM object to unmap
> + * @map: Kernel virtual address where the VRAM GEM object was mapped
> *
> * A call to drm_gem_vram_vunmap() unmaps and unpins a GEM VRAM buffer. See
> * the documentation for drm_gem_vram_vmap() for more information.
> */
> -void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr)
> +void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map)
> {
> int ret;
>
> @@ -481,7 +493,7 @@ void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr)
> if (WARN_ONCE(ret, "ttm_bo_reserve_failed(): ret=%d\n", ret))
> return;
>
> - drm_gem_vram_kunmap_locked(gbo);
> + drm_gem_vram_kunmap_locked(gbo, map);
> drm_gem_vram_unpin_locked(gbo);
>
> ttm_bo_unreserve(&gbo->bo);
> @@ -829,37 +841,33 @@ static void drm_gem_vram_object_unpin(struct drm_gem_object *gem)
> }
>
> /**
> - * drm_gem_vram_object_vmap() - \
> - Implements &struct drm_gem_object_funcs.vmap
> - * @gem: The GEM object to map
> + * drm_gem_vram_object_vmap() -
> + * Implements &struct drm_gem_object_funcs.vmap
> + * @gem: The GEM object to map
> + * @map: Returns the kernel virtual address of the VRAM GEM object's backing
> + * store.
> *
> * Returns:
> - * The buffers virtual address on success, or
> - * NULL otherwise.
> + * 0 on success, or a negative error code otherwise.
> */
> -static void *drm_gem_vram_object_vmap(struct drm_gem_object *gem)
> +static int drm_gem_vram_object_vmap(struct drm_gem_object *gem, struct dma_buf_map *map)
> {
> struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
> - void *base;
>
> - base = drm_gem_vram_vmap(gbo);
> - if (IS_ERR(base))
> - return NULL;
> - return base;
> + return drm_gem_vram_vmap(gbo, map);
> }
>
> /**
> - * drm_gem_vram_object_vunmap() - \
> - Implements &struct drm_gem_object_funcs.vunmap
> - * @gem: The GEM object to unmap
> - * @vaddr: The mapping's base address
> + * drm_gem_vram_object_vunmap() -
> + * Implements &struct drm_gem_object_funcs.vunmap
> + * @gem: The GEM object to unmap
> + * @map: Kernel virtual address where the VRAM GEM object was mapped
> */
> -static void drm_gem_vram_object_vunmap(struct drm_gem_object *gem,
> - void *vaddr)
> +static void drm_gem_vram_object_vunmap(struct drm_gem_object *gem, struct dma_buf_map *map)
> {
> struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
>
> - drm_gem_vram_vunmap(gbo, vaddr);
> + drm_gem_vram_vunmap(gbo, map);
> }
>
> /*
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.h b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
> index 914f0867ff71..3d1eb8065fce 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.h
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.h
> @@ -51,8 +51,8 @@ int etnaviv_ioctl_gem_submit(struct drm_device *dev, void *data,
> int etnaviv_gem_mmap(struct file *filp, struct vm_area_struct *vma);
> int etnaviv_gem_mmap_offset(struct drm_gem_object *obj, u64 *offset);
> struct sg_table *etnaviv_gem_prime_get_sg_table(struct drm_gem_object *obj);
> -void *etnaviv_gem_prime_vmap(struct drm_gem_object *obj);
> -void etnaviv_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int etnaviv_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void etnaviv_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> int etnaviv_gem_prime_mmap(struct drm_gem_object *obj,
> struct vm_area_struct *vma);
> struct drm_gem_object *etnaviv_gem_prime_import_sg_table(struct drm_device *dev,
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
> index 135fbff6fecf..36c03e287e29 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
> @@ -22,12 +22,17 @@ struct sg_table *etnaviv_gem_prime_get_sg_table(struct drm_gem_object *obj)
> return drm_prime_pages_to_sg(obj->dev, etnaviv_obj->pages, npages);
> }
>
> -void *etnaviv_gem_prime_vmap(struct drm_gem_object *obj)
> +int etnaviv_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> - return etnaviv_gem_vmap(obj);
> + void *vaddr = etnaviv_gem_vmap(obj);
> + if (!vaddr)
> + return -ENOMEM;
> + dma_buf_map_set_vaddr(map, vaddr);
> +
> + return 0;
> }
>
> -void etnaviv_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void etnaviv_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> /* TODO msm_gem_vunmap() */
> }
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
> index e7a6eb96f692..2c74e06669fa 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
> @@ -471,12 +471,12 @@ exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
> return &exynos_gem->base;
> }
>
> -void *exynos_drm_gem_prime_vmap(struct drm_gem_object *obj)
> +int exynos_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> - return NULL;
> + return -ENOMEM;
> }
>
> -void exynos_drm_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void exynos_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> /* Nothing to do */
> }

Might want to just start out with a patch to delete these. We don't keep
dummy functions around generally.

> diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.h b/drivers/gpu/drm/exynos/exynos_drm_gem.h
> index 74e926abeff0..ecfd048fd91d 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_gem.h
> +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.h
> @@ -107,8 +107,8 @@ struct drm_gem_object *
> exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
> struct dma_buf_attachment *attach,
> struct sg_table *sgt);
> -void *exynos_drm_gem_prime_vmap(struct drm_gem_object *obj);
> -void exynos_drm_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int exynos_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void exynos_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> int exynos_drm_gem_prime_mmap(struct drm_gem_object *obj,
> struct vm_area_struct *vma);
>
> diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c
> index 11223fe348df..832e5280a6ed 100644
> --- a/drivers/gpu/drm/lima/lima_gem.c
> +++ b/drivers/gpu/drm/lima/lima_gem.c
> @@ -182,14 +182,14 @@ static int lima_gem_pin(struct drm_gem_object *obj)
> return drm_gem_shmem_pin(obj);
> }
>
> -static void *lima_gem_vmap(struct drm_gem_object *obj)
> +static int lima_gem_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct lima_bo *bo = to_lima_bo(obj);
>
> if (bo->heap_size)
> - return ERR_PTR(-EINVAL);
> + return -EINVAL;
>
> - return drm_gem_shmem_vmap(obj);
> + return drm_gem_shmem_vmap(obj, map);
> }
>
> static int lima_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
> diff --git a/drivers/gpu/drm/lima/lima_sched.c b/drivers/gpu/drm/lima/lima_sched.c
> index dc6df9e9a40d..a070a85f8f36 100644
> --- a/drivers/gpu/drm/lima/lima_sched.c
> +++ b/drivers/gpu/drm/lima/lima_sched.c
> @@ -1,6 +1,7 @@
> // SPDX-License-Identifier: GPL-2.0 OR MIT
> /* Copyright 2017-2019 Qiang Yu <yuq825@gmail.com> */
>
> +#include <linux/dma-buf-map.h>
> #include <linux/kthread.h>
> #include <linux/slab.h>
> #include <linux/vmalloc.h>
> @@ -303,6 +304,8 @@ static void lima_sched_build_error_task_list(struct lima_sched_task *task)
> struct lima_dump_chunk_buffer *buffer_chunk;
> u32 size, task_size, mem_size;
> int i;
> + struct dma_buf_map map;
> + int ret;
>
> mutex_lock(&dev->error_task_list_lock);
>
> @@ -388,15 +391,15 @@ static void lima_sched_build_error_task_list(struct lima_sched_task *task)
> } else {
> buffer_chunk->size = lima_bo_size(bo);
>
> - data = drm_gem_shmem_vmap(&bo->base.base);
> - if (IS_ERR_OR_NULL(data)) {
> + ret = drm_gem_shmem_vmap(&bo->base.base, &map);
> + if (ret) {
> kvfree(et);
> goto out;
> }
>
> - memcpy(buffer_chunk + 1, data, buffer_chunk->size);
> + memcpy(buffer_chunk + 1, map.vaddr, buffer_chunk->size);
>
> - drm_gem_shmem_vunmap(&bo->base.base, data);
> + drm_gem_shmem_vunmap(&bo->base.base, &map);
> }
>
> buffer_chunk = (void *)(buffer_chunk + 1) + buffer_chunk->size;
> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
> index 38672f9e5c4f..ae4c8cb33fae 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
> @@ -9,6 +9,7 @@
> */
>
> #include <linux/delay.h>
> +#include <linux/dma-buf-map.h>
>
> #include <drm/drm_atomic_helper.h>
> #include <drm/drm_atomic_state_helper.h>
> @@ -1556,15 +1557,16 @@ mgag200_handle_damage(struct mga_device *mdev, struct drm_framebuffer *fb,
> struct drm_rect *clip)
> {
> struct drm_device *dev = &mdev->base;
> - void *vmap;
> + struct dma_buf_map map;
> + int ret;
>
> - vmap = drm_gem_shmem_vmap(fb->obj[0]);
> - if (drm_WARN_ON(dev, !vmap))
> + ret = drm_gem_shmem_vmap(fb->obj[0], &map);
> + if (drm_WARN_ON(dev, ret))
> return; /* BUG: SHMEM BO should always be vmapped */
>
> - drm_fb_memcpy_dstclip(mdev->vram, vmap, fb, clip);
> + drm_fb_memcpy_dstclip(mdev->vram, map.vaddr, fb, clip);
>
> - drm_gem_shmem_vunmap(fb->obj[0], vmap);
> + drm_gem_shmem_vunmap(fb->obj[0], &map);
>
> /* Always scanout image at VRAM offset 0 */
> mgag200_set_startadd(mdev, (u32)0);
> diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.h b/drivers/gpu/drm/nouveau/nouveau_gem.h
> index b35c180322e2..e780b6b1763d 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_gem.h
> +++ b/drivers/gpu/drm/nouveau/nouveau_gem.h
> @@ -37,7 +37,7 @@ extern void nouveau_gem_prime_unpin(struct drm_gem_object *);
> extern struct sg_table *nouveau_gem_prime_get_sg_table(struct drm_gem_object *);
> extern struct drm_gem_object *nouveau_gem_prime_import_sg_table(
> struct drm_device *, struct dma_buf_attachment *, struct sg_table *);
> -extern void *nouveau_gem_prime_vmap(struct drm_gem_object *);
> -extern void nouveau_gem_prime_vunmap(struct drm_gem_object *, void *);
> +extern int nouveau_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +extern void nouveau_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> #endif
> diff --git a/drivers/gpu/drm/nouveau/nouveau_prime.c b/drivers/gpu/drm/nouveau/nouveau_prime.c
> index a8264aebf3d4..75e973a5675a 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_prime.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_prime.c
> @@ -35,7 +35,7 @@ struct sg_table *nouveau_gem_prime_get_sg_table(struct drm_gem_object *obj)
> return drm_prime_pages_to_sg(obj->dev, nvbo->bo.ttm->pages, npages);
> }
>
> -void *nouveau_gem_prime_vmap(struct drm_gem_object *obj)
> +int nouveau_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct nouveau_bo *nvbo = nouveau_gem_object(obj);
> int ret;
> @@ -43,12 +43,13 @@ void *nouveau_gem_prime_vmap(struct drm_gem_object *obj)
> ret = ttm_bo_kmap(&nvbo->bo, 0, nvbo->bo.num_pages,
> &nvbo->dma_buf_vmap);
> if (ret)
> - return ERR_PTR(ret);
> + return ret;
> + ttm_kmap_obj_to_dma_buf_map(&nvbo->dma_buf_vmap, map);
>
> - return nvbo->dma_buf_vmap.virtual;
> + return 0;
> }
>
> -void nouveau_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void nouveau_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct nouveau_bo *nvbo = nouveau_gem_object(obj);
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_perfcnt.c b/drivers/gpu/drm/panfrost/panfrost_perfcnt.c
> index fdbc8d949135..5ab03d605f57 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_perfcnt.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_perfcnt.c
> @@ -5,6 +5,7 @@
> #include <drm/drm_gem_shmem_helper.h>
> #include <drm/panfrost_drm.h>
> #include <linux/completion.h>
> +#include <linux/dma-buf-map.h>
> #include <linux/iopoll.h>
> #include <linux/pm_runtime.h>
> #include <linux/slab.h>
> @@ -72,6 +73,7 @@ static int panfrost_perfcnt_enable_locked(struct panfrost_device *pfdev,
> {
> struct panfrost_file_priv *user = file_priv->driver_priv;
> struct panfrost_perfcnt *perfcnt = pfdev->perfcnt;
> + struct dma_buf_map map;
> struct drm_gem_shmem_object *bo;
> u32 cfg, as;
> int ret;
> @@ -103,11 +105,10 @@ static int panfrost_perfcnt_enable_locked(struct panfrost_device *pfdev,
> goto err_close_bo;
> }
>
> - perfcnt->buf = drm_gem_shmem_vmap(&bo->base);
> - if (IS_ERR(perfcnt->buf)) {
> - ret = PTR_ERR(perfcnt->buf);
> + ret = drm_gem_shmem_vmap(&bo->base, &map);
> + if (ret)
> goto err_put_mapping;
> - }
> + perfcnt->buf = map.vaddr;
>
> /*
> * Invalidate the cache and clear the counters to start from a fresh
> @@ -163,7 +164,7 @@ static int panfrost_perfcnt_enable_locked(struct panfrost_device *pfdev,
> return 0;
>
> err_vunmap:
> - drm_gem_shmem_vunmap(&bo->base, perfcnt->buf);
> + drm_gem_shmem_vunmap(&bo->base, &map);
> err_put_mapping:
> panfrost_gem_mapping_put(perfcnt->mapping);
> err_close_bo:
> @@ -180,6 +181,7 @@ static int panfrost_perfcnt_disable_locked(struct panfrost_device *pfdev,
> {
> struct panfrost_file_priv *user = file_priv->driver_priv;
> struct panfrost_perfcnt *perfcnt = pfdev->perfcnt;
> + struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(perfcnt->buf);
>
> if (user != perfcnt->user)
> return -EINVAL;
> @@ -192,7 +194,7 @@ static int panfrost_perfcnt_disable_locked(struct panfrost_device *pfdev,
> GPU_PERFCNT_CFG_MODE(GPU_PERFCNT_CFG_MODE_OFF));
>
> perfcnt->user = NULL;
> - drm_gem_shmem_vunmap(&perfcnt->mapping->obj->base.base, perfcnt->buf);
> + drm_gem_shmem_vunmap(&perfcnt->mapping->obj->base.base, &map);
> perfcnt->buf = NULL;
> panfrost_gem_close(&perfcnt->mapping->obj->base.base, file_priv);
> panfrost_mmu_as_put(pfdev, perfcnt->mapping->mmu);
> diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
> index 6063f3a15329..ed0d22fa0161 100644
> --- a/drivers/gpu/drm/qxl/qxl_display.c
> +++ b/drivers/gpu/drm/qxl/qxl_display.c
> @@ -25,6 +25,7 @@
>
> #include <linux/crc32.h>
> #include <linux/delay.h>
> +#include <linux/dma-buf-map.h>
>
> #include <drm/drm_drv.h>
> #include <drm/drm_atomic.h>
> @@ -581,7 +582,8 @@ static void qxl_cursor_atomic_update(struct drm_plane *plane,
> struct drm_gem_object *obj;
> struct qxl_bo *cursor_bo = NULL, *user_bo = NULL, *old_cursor_bo = NULL;
> int ret;
> - void *user_ptr;
> + struct dma_buf_map user_map;
> + struct dma_buf_map cursor_map;
> int size = 64*64*4;
>
> ret = qxl_alloc_release_reserved(qdev, sizeof(*cmd),
> @@ -595,7 +597,7 @@ static void qxl_cursor_atomic_update(struct drm_plane *plane,
> user_bo = gem_to_qxl_bo(obj);
>
> /* pinning is done in the prepare/cleanup framevbuffer */
> - ret = qxl_bo_kmap(user_bo, &user_ptr);
> + ret = qxl_bo_kmap(user_bo, &user_map);
> if (ret)
> goto out_free_release;
>
> @@ -613,7 +615,7 @@ static void qxl_cursor_atomic_update(struct drm_plane *plane,
> if (ret)
> goto out_unpin;
>
> - ret = qxl_bo_kmap(cursor_bo, (void **)&cursor);
> + ret = qxl_bo_kmap(cursor_bo, &cursor_map);
> if (ret)
> goto out_backoff;
>
> @@ -627,7 +629,7 @@ static void qxl_cursor_atomic_update(struct drm_plane *plane,
> cursor->chunk.next_chunk = 0;
> cursor->chunk.prev_chunk = 0;
> cursor->chunk.data_size = size;
> - memcpy(cursor->chunk.data, user_ptr, size);
> + memcpy(cursor->chunk.data, user_map.vaddr, size);
> qxl_bo_kunmap(cursor_bo);
> qxl_bo_kunmap(user_bo);
>
> @@ -1138,6 +1140,7 @@ int qxl_create_monitors_object(struct qxl_device *qdev)
> {
> int ret;
> struct drm_gem_object *gobj;
> + struct dma_buf_map map;
> int monitors_config_size = sizeof(struct qxl_monitors_config) +
> qxl_num_crtc * sizeof(struct qxl_head);
>
> @@ -1154,7 +1157,7 @@ int qxl_create_monitors_object(struct qxl_device *qdev)
> if (ret)
> return ret;
>
> - qxl_bo_kmap(qdev->monitors_config_bo, NULL);
> + qxl_bo_kmap(qdev->monitors_config_bo, &map);
>
> qdev->monitors_config = qdev->monitors_config_bo->kptr;
> qdev->ram_header->monitors_config =
> diff --git a/drivers/gpu/drm/qxl/qxl_draw.c b/drivers/gpu/drm/qxl/qxl_draw.c
> index 3599db096973..1bf4f465ecf4 100644
> --- a/drivers/gpu/drm/qxl/qxl_draw.c
> +++ b/drivers/gpu/drm/qxl/qxl_draw.c
> @@ -20,6 +20,8 @@
> * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
> */
>
> +#include <linux/dma-buf-map.h>
> +
> #include <drm/drm_fourcc.h>
>
> #include "qxl_drv.h"
> @@ -42,13 +44,15 @@ static struct qxl_rect *drawable_set_clipping(struct qxl_device *qdev,
> unsigned int num_clips,
> struct qxl_bo *clips_bo)
> {
> + struct dma_buf_map map;
> struct qxl_clip_rects *dev_clips;
> int ret;
>
> - ret = qxl_bo_kmap(clips_bo, (void **)&dev_clips);
> - if (ret) {
> + ret = qxl_bo_kmap(clips_bo, &map);
> + if (ret)
> return NULL;
> - }
> +
> + dev_clips = map.vaddr;
> dev_clips->num_rects = num_clips;
> dev_clips->chunk.next_chunk = 0;
> dev_clips->chunk.prev_chunk = 0;
> @@ -142,7 +146,7 @@ void qxl_draw_dirty_fb(struct qxl_device *qdev,
> int stride = fb->pitches[0];
> /* depth is not actually interesting, we don't mask with it */
> int depth = fb->format->cpp[0] * 8;
> - uint8_t *surface_base;
> + struct dma_buf_map surface_map;
> struct qxl_release *release;
> struct qxl_bo *clips_bo;
> struct qxl_drm_image *dimage;
> @@ -197,11 +201,11 @@ void qxl_draw_dirty_fb(struct qxl_device *qdev,
> if (ret)
> goto out_release_backoff;
>
> - ret = qxl_bo_kmap(bo, (void **)&surface_base);
> + ret = qxl_bo_kmap(bo, &surface_map);
> if (ret)
> goto out_release_backoff;
>
> - ret = qxl_image_init(qdev, release, dimage, surface_base,
> + ret = qxl_image_init(qdev, release, dimage, surface_map.vaddr,
> left - dumb_shadow_offset,
> top, width, height, depth, stride);
> qxl_bo_kunmap(bo);
> diff --git a/drivers/gpu/drm/qxl/qxl_drv.h b/drivers/gpu/drm/qxl/qxl_drv.h
> index 3602e8b34189..a9e9da4f4605 100644
> --- a/drivers/gpu/drm/qxl/qxl_drv.h
> +++ b/drivers/gpu/drm/qxl/qxl_drv.h
> @@ -50,6 +50,8 @@
>
> #include "qxl_dev.h"
>
> +struct dma_buf_map;
> +
> #define DRIVER_AUTHOR "Dave Airlie"
>
> #define DRIVER_NAME "qxl"
> @@ -335,7 +337,6 @@ int qxl_gem_object_open(struct drm_gem_object *obj, struct drm_file *file_priv);
> void qxl_gem_object_close(struct drm_gem_object *obj,
> struct drm_file *file_priv);
> void qxl_bo_force_delete(struct qxl_device *qdev);
> -int qxl_bo_kmap(struct qxl_bo *bo, void **ptr);
>
> /* qxl_dumb.c */
> int qxl_mode_dumb_create(struct drm_file *file_priv,
> @@ -445,8 +446,9 @@ struct sg_table *qxl_gem_prime_get_sg_table(struct drm_gem_object *obj);
> struct drm_gem_object *qxl_gem_prime_import_sg_table(
> struct drm_device *dev, struct dma_buf_attachment *attach,
> struct sg_table *sgt);
> -void *qxl_gem_prime_vmap(struct drm_gem_object *obj);
> -void qxl_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int qxl_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void qxl_gem_prime_vunmap(struct drm_gem_object *obj,
> + struct dma_buf_map *map);
> int qxl_gem_prime_mmap(struct drm_gem_object *obj,
> struct vm_area_struct *vma);
>
> diff --git a/drivers/gpu/drm/qxl/qxl_object.c b/drivers/gpu/drm/qxl/qxl_object.c
> index d3635e3e3267..2d8ae3b10b1c 100644
> --- a/drivers/gpu/drm/qxl/qxl_object.c
> +++ b/drivers/gpu/drm/qxl/qxl_object.c
> @@ -23,10 +23,12 @@
> * Alon Levy
> */
>
> +#include <linux/dma-buf-map.h>
> +#include <linux/io-mapping.h>
> +
> #include "qxl_drv.h"
> #include "qxl_object.h"
>
> -#include <linux/io-mapping.h>
> static void qxl_ttm_bo_destroy(struct ttm_buffer_object *tbo)
> {
> struct qxl_bo *bo;
> @@ -150,24 +152,22 @@ int qxl_bo_create(struct qxl_device *qdev,
> return 0;
> }
>
> -int qxl_bo_kmap(struct qxl_bo *bo, void **ptr)
> +int qxl_bo_kmap(struct qxl_bo *bo, struct dma_buf_map *map)
> {
> - bool is_iomem;
> int r;
>
> if (bo->kptr) {
> - if (ptr)
> - *ptr = bo->kptr;
> bo->map_count++;
> - return 0;
> + goto out;
> }
> r = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages, &bo->kmap);
> if (r)
> return r;
> - bo->kptr = ttm_kmap_obj_virtual(&bo->kmap, &is_iomem);
> - if (ptr)
> - *ptr = bo->kptr;
> bo->map_count = 1;
> + bo->kptr = bo->kmap.virtual;
> +
> +out:
> + ttm_kmap_obj_to_dma_buf_map(&bo->kmap, map);
> return 0;
> }
>
> @@ -178,6 +178,7 @@ void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,
> void *rptr;
> int ret;
> struct io_mapping *map;
> + struct dma_buf_map bo_map;
>
> if (bo->tbo.mem.mem_type == TTM_PL_VRAM)
> map = qdev->vram_mapping;
> @@ -194,11 +195,11 @@ void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev,

Uh, this fallback is wild. Not exactly sure this is a good idea or
anything, but also it's here already :-)

> return rptr;
> }
>
> - ret = qxl_bo_kmap(bo, &rptr);
> + ret = qxl_bo_kmap(bo, &bo_map);
> if (ret)
> return NULL;
>
> - rptr += page_offset * PAGE_SIZE;
> + rptr = bo_map.vaddr + page_offset * PAGE_SIZE;
> return rptr;
> }
>
> diff --git a/drivers/gpu/drm/qxl/qxl_object.h b/drivers/gpu/drm/qxl/qxl_object.h
> index 09a5c818324d..ebf24c9d2bf2 100644
> --- a/drivers/gpu/drm/qxl/qxl_object.h
> +++ b/drivers/gpu/drm/qxl/qxl_object.h
> @@ -63,7 +63,7 @@ extern int qxl_bo_create(struct qxl_device *qdev,
> bool kernel, bool pinned, u32 domain,
> struct qxl_surface *surf,
> struct qxl_bo **bo_ptr);
> -extern int qxl_bo_kmap(struct qxl_bo *bo, void **ptr);
> +extern int qxl_bo_kmap(struct qxl_bo *bo, struct dma_buf_map *map);
> extern void qxl_bo_kunmap(struct qxl_bo *bo);
> void *qxl_bo_kmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, int page_offset);
> void qxl_bo_kunmap_atomic_page(struct qxl_device *qdev, struct qxl_bo *bo, void *map);
> diff --git a/drivers/gpu/drm/qxl/qxl_prime.c b/drivers/gpu/drm/qxl/qxl_prime.c
> index 7d3816fca5a8..4aa949799446 100644
> --- a/drivers/gpu/drm/qxl/qxl_prime.c
> +++ b/drivers/gpu/drm/qxl/qxl_prime.c
> @@ -54,20 +54,20 @@ struct drm_gem_object *qxl_gem_prime_import_sg_table(
> return ERR_PTR(-ENOSYS);
> }
>
> -void *qxl_gem_prime_vmap(struct drm_gem_object *obj)
> +int qxl_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct qxl_bo *bo = gem_to_qxl_bo(obj);
> - void *ptr;
> int ret;
>
> - ret = qxl_bo_kmap(bo, &ptr);
> + ret = qxl_bo_kmap(bo, map);
> if (ret < 0)
> - return ERR_PTR(ret);
> + return ret;
>
> - return ptr;
> + return 0;
> }
>
> -void qxl_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void qxl_gem_prime_vunmap(struct drm_gem_object *obj,
> + struct dma_buf_map *map)
> {
> struct qxl_bo *bo = gem_to_qxl_bo(obj);
>
> diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
> index 0ccd7213e41f..ac51517bdfcd 100644
> --- a/drivers/gpu/drm/radeon/radeon_gem.c
> +++ b/drivers/gpu/drm/radeon/radeon_gem.c
> @@ -40,8 +40,8 @@ struct dma_buf *radeon_gem_prime_export(struct drm_gem_object *gobj,
> struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj);
> int radeon_gem_prime_pin(struct drm_gem_object *obj);
> void radeon_gem_prime_unpin(struct drm_gem_object *obj);
> -void *radeon_gem_prime_vmap(struct drm_gem_object *obj);
> -void radeon_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int radeon_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void radeon_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> static const struct drm_gem_object_funcs radeon_gem_object_funcs;
>
> diff --git a/drivers/gpu/drm/radeon/radeon_prime.c b/drivers/gpu/drm/radeon/radeon_prime.c
> index b9de0e51c0be..a1a358de5448 100644
> --- a/drivers/gpu/drm/radeon/radeon_prime.c
> +++ b/drivers/gpu/drm/radeon/radeon_prime.c
> @@ -39,7 +39,7 @@ struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj)
> return drm_prime_pages_to_sg(obj->dev, bo->tbo.ttm->pages, npages);
> }
>
> -void *radeon_gem_prime_vmap(struct drm_gem_object *obj)
> +int radeon_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct radeon_bo *bo = gem_to_radeon_bo(obj);
> int ret;
> @@ -47,12 +47,13 @@ void *radeon_gem_prime_vmap(struct drm_gem_object *obj)
> ret = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages,
> &bo->dma_buf_vmap);
> if (ret)
> - return ERR_PTR(ret);
> + return ret;
> + ttm_kmap_obj_to_dma_buf_map(&bo->dma_buf_vmap, map);
>
> - return bo->dma_buf_vmap.virtual;
> + return 0;
> }
>
> -void radeon_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void radeon_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct radeon_bo *bo = gem_to_radeon_bo(obj);
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> index 7d5ebb10323b..7971f57436dd 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c
> @@ -532,26 +532,32 @@ rockchip_gem_prime_import_sg_table(struct drm_device *drm,
> return ERR_PTR(ret);
> }
>
> -void *rockchip_gem_prime_vmap(struct drm_gem_object *obj)
> +int rockchip_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
>
> - if (rk_obj->pages)
> - return vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
> - pgprot_writecombine(PAGE_KERNEL));
> + if (rk_obj->pages) {
> + void *vaddr = vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
> + pgprot_writecombine(PAGE_KERNEL));
> + if (!vaddr)
> + return -ENOMEM;
> + dma_buf_map_set_vaddr(map, vaddr);
> + return 0;
> + }
>
> if (rk_obj->dma_attrs & DMA_ATTR_NO_KERNEL_MAPPING)
> - return NULL;
> + return -ENOMEM;
> + dma_buf_map_set_vaddr(map, rk_obj->kvaddr);
>
> - return rk_obj->kvaddr;
> + return 0;
> }
>
> -void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
>
> if (rk_obj->pages) {
> - vunmap(vaddr);
> + vunmap(map->vaddr);
> return;
> }
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.h b/drivers/gpu/drm/rockchip/rockchip_drm_gem.h
> index 7ffc541bea07..5a70a56cd406 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.h
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.h
> @@ -31,8 +31,8 @@ struct drm_gem_object *
> rockchip_gem_prime_import_sg_table(struct drm_device *dev,
> struct dma_buf_attachment *attach,
> struct sg_table *sg);
> -void *rockchip_gem_prime_vmap(struct drm_gem_object *obj);
> -void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int rockchip_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void rockchip_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> /* drm driver mmap file operations */
> int rockchip_gem_mmap(struct file *filp, struct vm_area_struct *vma);
> diff --git a/drivers/gpu/drm/tiny/cirrus.c b/drivers/gpu/drm/tiny/cirrus.c
> index 744a8e337e41..6dc013f4b236 100644
> --- a/drivers/gpu/drm/tiny/cirrus.c
> +++ b/drivers/gpu/drm/tiny/cirrus.c
> @@ -17,6 +17,7 @@
> */
>
> #include <linux/console.h>
> +#include <linux/dma-buf-map.h>
> #include <linux/module.h>
> #include <linux/pci.h>
>
> @@ -314,6 +315,7 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb,
> struct drm_rect *rect)
> {
> struct cirrus_device *cirrus = to_cirrus(fb->dev);
> + struct dma_buf_map map;
> void *vmap;
> int idx, ret;
>
> @@ -321,10 +323,10 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb,
> if (!drm_dev_enter(&cirrus->dev, &idx))
> goto out;
>
> - ret = -ENOMEM;
> - vmap = drm_gem_shmem_vmap(fb->obj[0]);
> - if (!vmap)
> + ret = drm_gem_shmem_vmap(fb->obj[0], &map);
> + if (ret)
> goto out_dev_exit;
> + vmap = map.vaddr;
>
> if (cirrus->cpp == fb->format->cpp[0])
> drm_fb_memcpy_dstclip(cirrus->vram,
> @@ -343,7 +345,7 @@ static int cirrus_fb_blit_rect(struct drm_framebuffer *fb,
> else
> WARN_ON_ONCE("cpp mismatch");
>
> - drm_gem_shmem_vunmap(fb->obj[0], vmap);
> + drm_gem_shmem_vunmap(fb->obj[0], &map);
> ret = 0;
>
> out_dev_exit:
> diff --git a/drivers/gpu/drm/tiny/gm12u320.c b/drivers/gpu/drm/tiny/gm12u320.c
> index cc397671f689..5865027a1667 100644
> --- a/drivers/gpu/drm/tiny/gm12u320.c
> +++ b/drivers/gpu/drm/tiny/gm12u320.c
> @@ -248,6 +248,7 @@ static void gm12u320_copy_fb_to_blocks(struct gm12u320_device *gm12u320)
> {
> int block, dst_offset, len, remain, ret, x1, x2, y1, y2;
> struct drm_framebuffer *fb;
> + struct dma_buf_map map;
> void *vaddr;
> u8 *src;
>
> @@ -262,11 +263,12 @@ static void gm12u320_copy_fb_to_blocks(struct gm12u320_device *gm12u320)
> y1 = gm12u320->fb_update.rect.y1;
> y2 = gm12u320->fb_update.rect.y2;
>
> - vaddr = drm_gem_shmem_vmap(fb->obj[0]);
> - if (IS_ERR(vaddr)) {
> - GM12U320_ERR("failed to vmap fb: %ld\n", PTR_ERR(vaddr));
> + ret = drm_gem_shmem_vmap(fb->obj[0], &map);
> + if (ret) {
> + GM12U320_ERR("failed to vmap fb: %d\n", ret);
> goto put_fb;
> }
> + vaddr = map.vaddr;
>
> if (fb->obj[0]->import_attach) {
> ret = dma_buf_begin_cpu_access(
> @@ -318,7 +320,7 @@ static void gm12u320_copy_fb_to_blocks(struct gm12u320_device *gm12u320)
> GM12U320_ERR("dma_buf_end_cpu_access err: %d\n", ret);
> }
> vunmap:
> - drm_gem_shmem_vunmap(fb->obj[0], vaddr);
> + drm_gem_shmem_vunmap(fb->obj[0], &map);
> put_fb:
> drm_framebuffer_put(fb);
> gm12u320->fb_update.fb = NULL;
> diff --git a/drivers/gpu/drm/udl/udl_modeset.c b/drivers/gpu/drm/udl/udl_modeset.c
> index fef43f4e3bac..9c8ace1aa647 100644
> --- a/drivers/gpu/drm/udl/udl_modeset.c
> +++ b/drivers/gpu/drm/udl/udl_modeset.c
> @@ -276,6 +276,7 @@ static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
> struct urb *urb;
> struct drm_rect clip;
> int log_bpp;
> + struct dma_buf_map map;
> void *vaddr;
>
> ret = udl_log_cpp(fb->format->cpp[0]);
> @@ -296,11 +297,12 @@ static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
> return ret;
> }
>
> - vaddr = drm_gem_shmem_vmap(fb->obj[0]);
> - if (IS_ERR(vaddr)) {
> + ret = drm_gem_shmem_vmap(fb->obj[0], &map);
> + if (ret) {
> DRM_ERROR("failed to vmap fb\n");
> goto out_dma_buf_end_cpu_access;
> }
> + vaddr = map.vaddr;
>
> urb = udl_get_urb(dev);
> if (!urb)
> @@ -333,7 +335,7 @@ static int udl_handle_damage(struct drm_framebuffer *fb, int x, int y,
> ret = 0;
>
> out_drm_gem_shmem_vunmap:
> - drm_gem_shmem_vunmap(fb->obj[0], vaddr);
> + drm_gem_shmem_vunmap(fb->obj[0], &map);
> out_dma_buf_end_cpu_access:
> if (import_attach) {
> tmp_ret = dma_buf_end_cpu_access(import_attach->dmabuf,
> diff --git a/drivers/gpu/drm/vboxvideo/vbox_mode.c b/drivers/gpu/drm/vboxvideo/vbox_mode.c
> index 4fcc0a542b8a..6040b9ec747f 100644
> --- a/drivers/gpu/drm/vboxvideo/vbox_mode.c
> +++ b/drivers/gpu/drm/vboxvideo/vbox_mode.c
> @@ -9,6 +9,8 @@
> * Michael Thayer <michael.thayer@oracle.com,
> * Hans de Goede <hdegoede@redhat.com>
> */
> +
> +#include <linux/dma-buf-map.h>
> #include <linux/export.h>
>
> #include <drm/drm_atomic.h>
> @@ -384,6 +386,8 @@ static void vbox_cursor_atomic_update(struct drm_plane *plane,
> u32 height = plane->state->crtc_h;
> size_t data_size, mask_size;
> u32 flags;
> + struct dma_buf_map map;
> + int ret;
> u8 *src;
>
> /*
> @@ -397,8 +401,8 @@ static void vbox_cursor_atomic_update(struct drm_plane *plane,
>
> vbox_crtc->cursor_enabled = true;
>
> - src = drm_gem_vram_vmap(gbo);
> - if (IS_ERR(src)) {
> + ret = drm_gem_vram_vmap(gbo, &map);
> + if (ret) {
> /*
> * BUG: we should have pinned the BO in prepare_fb().
> */
> @@ -406,6 +410,7 @@ static void vbox_cursor_atomic_update(struct drm_plane *plane,
> DRM_WARN("Could not map cursor bo, skipping update\n");
> return;
> }

I don't think digging around in the pointer is a good idea, imo this
should get a

/* FIXME: Use mapping abstraction properly */

or similar.

> + src = map.vaddr;
>
> /*
> * The mask must be calculated based on the alpha
> @@ -416,7 +421,7 @@ static void vbox_cursor_atomic_update(struct drm_plane *plane,
> data_size = width * height * 4 + mask_size;
>
> copy_cursor_image(src, vbox->cursor_data, width, height, mask_size);
> - drm_gem_vram_vunmap(gbo, src);
> + drm_gem_vram_vunmap(gbo, &map);
>
> flags = VBOX_MOUSE_POINTER_VISIBLE | VBOX_MOUSE_POINTER_SHAPE |
> VBOX_MOUSE_POINTER_ALPHA;
> diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c
> index f432278173cd..250266fb437e 100644
> --- a/drivers/gpu/drm/vc4/vc4_bo.c
> +++ b/drivers/gpu/drm/vc4/vc4_bo.c
> @@ -786,16 +786,16 @@ int vc4_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
> return drm_gem_cma_prime_mmap(obj, vma);
> }
>
> -void *vc4_prime_vmap(struct drm_gem_object *obj)
> +int vc4_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct vc4_bo *bo = to_vc4_bo(obj);
>
> if (bo->validated_shader) {
> DRM_DEBUG("mmaping of shader BOs not allowed.\n");
> - return ERR_PTR(-EINVAL);
> + return -EINVAL;
> }
>
> - return drm_gem_cma_prime_vmap(obj);
> + return drm_gem_cma_prime_vmap(obj, map);
> }
>
> struct drm_gem_object *
> diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h
> index a22478a35199..6af453c84777 100644
> --- a/drivers/gpu/drm/vc4/vc4_drv.h
> +++ b/drivers/gpu/drm/vc4/vc4_drv.h
> @@ -804,7 +804,7 @@ int vc4_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);
> struct drm_gem_object *vc4_prime_import_sg_table(struct drm_device *dev,
> struct dma_buf_attachment *attach,
> struct sg_table *sgt);
> -void *vc4_prime_vmap(struct drm_gem_object *obj);
> +int vc4_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> int vc4_bo_cache_init(struct drm_device *dev);
> void vc4_bo_cache_destroy(struct drm_device *dev);
> int vc4_bo_inc_usecnt(struct vc4_bo *bo);
> diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c
> index fa54a6d1403d..b2aa26e1e4a2 100644
> --- a/drivers/gpu/drm/vgem/vgem_drv.c
> +++ b/drivers/gpu/drm/vgem/vgem_drv.c
> @@ -361,24 +361,30 @@ static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,
> return &obj->base;
> }
>
> -static void *vgem_prime_vmap(struct drm_gem_object *obj)
> +static int vgem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
> long n_pages = obj->size >> PAGE_SHIFT;
> struct page **pages;
> + void *vaddr;
>
> pages = vgem_pin_pages(bo);
> if (IS_ERR(pages))
> - return NULL;
> + return PTR_ERR(pages);
> +
> + vaddr = vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
> + if (!vaddr)
> + return -ENOMEM;
> + dma_buf_map_set_vaddr(map, vaddr);
>
> - return vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
> + return 0;
> }
>
> -static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
> +static void vgem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
> {
> struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
>
> - vunmap(vaddr);
> + vunmap(map->vaddr);
> vgem_unpin_pages(bo);
> }
>
> diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c
> index 4f34ef34ba60..74db5a840bed 100644
> --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c
> +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c
> @@ -290,22 +290,28 @@ int xen_drm_front_gem_mmap(struct file *filp, struct vm_area_struct *vma)
> return gem_mmap_obj(xen_obj, vma);
> }
>
> -void *xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj)
> +int xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj, struct dma_buf_map *map)
> {
> struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj);
> + void *vaddr;
>
> if (!xen_obj->pages)
> - return NULL;
> + return -ENOMEM;
>
> /* Please see comment in gem_mmap_obj on mapping and attributes. */
> - return vmap(xen_obj->pages, xen_obj->num_pages,
> - VM_MAP, PAGE_KERNEL);
> + vaddr = vmap(xen_obj->pages, xen_obj->num_pages,
> + VM_MAP, PAGE_KERNEL);
> + if (!vaddr)
> + return -ENOMEM;
> + dma_buf_map_set_vaddr(map, vaddr);
> +
> + return 0;
> }
>
> void xen_drm_front_gem_prime_vunmap(struct drm_gem_object *gem_obj,
> - void *vaddr)
> + struct dma_buf_map *map)
> {
> - vunmap(vaddr);
> + vunmap(map->vaddr);
> }
>
> int xen_drm_front_gem_prime_mmap(struct drm_gem_object *gem_obj,
> diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.h b/drivers/gpu/drm/xen/xen_drm_front_gem.h
> index a39675fa31b2..a4e67d0a149c 100644
> --- a/drivers/gpu/drm/xen/xen_drm_front_gem.h
> +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.h
> @@ -12,6 +12,7 @@
> #define __XEN_DRM_FRONT_GEM_H
>
> struct dma_buf_attachment;
> +struct dma_buf_map;
> struct drm_device;
> struct drm_gem_object;
> struct file;
> @@ -34,10 +35,11 @@ void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj);
>
> int xen_drm_front_gem_mmap(struct file *filp, struct vm_area_struct *vma);
>
> -void *xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj);
> +int xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj,
> + struct dma_buf_map *map);
>
> void xen_drm_front_gem_prime_vunmap(struct drm_gem_object *gem_obj,
> - void *vaddr);
> + struct dma_buf_map *map);
>
> int xen_drm_front_gem_prime_mmap(struct drm_gem_object *gem_obj,
> struct vm_area_struct *vma);
> diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
> index c38dd35da00b..5e6daa1c982f 100644
> --- a/include/drm/drm_gem.h
> +++ b/include/drm/drm_gem.h
> @@ -39,6 +39,7 @@
>
> #include <drm/drm_vma_manager.h>
>
> +struct dma_buf_map;
> struct drm_gem_object;
>
> /**
> @@ -138,7 +139,7 @@ struct drm_gem_object_funcs {
> *
> * This callback is optional.
> */
> - void *(*vmap)(struct drm_gem_object *obj);
> + int (*vmap)(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> /**
> * @vunmap:
> @@ -148,7 +149,7 @@ struct drm_gem_object_funcs {
> *
> * This callback is optional.
> */
> - void (*vunmap)(struct drm_gem_object *obj, void *vaddr);
> + void (*vunmap)(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> /**
> * @mmap:
> diff --git a/include/drm/drm_gem_cma_helper.h b/include/drm/drm_gem_cma_helper.h
> index 2bfa2502607a..34a7f72879c5 100644
> --- a/include/drm/drm_gem_cma_helper.h
> +++ b/include/drm/drm_gem_cma_helper.h
> @@ -103,8 +103,8 @@ drm_gem_cma_prime_import_sg_table(struct drm_device *dev,
> struct sg_table *sgt);
> int drm_gem_cma_prime_mmap(struct drm_gem_object *obj,
> struct vm_area_struct *vma);
> -void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj);
> -void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int drm_gem_cma_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> struct drm_gem_object *
> drm_gem_cma_create_object_default_funcs(struct drm_device *dev, size_t size);
> diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h
> index 5381f0c8cf6f..3449a0353fe0 100644
> --- a/include/drm/drm_gem_shmem_helper.h
> +++ b/include/drm/drm_gem_shmem_helper.h
> @@ -113,8 +113,8 @@ int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem);
> void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem);
> int drm_gem_shmem_pin(struct drm_gem_object *obj);
> void drm_gem_shmem_unpin(struct drm_gem_object *obj);
> -void *drm_gem_shmem_vmap(struct drm_gem_object *obj);
> -void drm_gem_shmem_vunmap(struct drm_gem_object *obj, void *vaddr);
> +int drm_gem_shmem_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
> +void drm_gem_shmem_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
>
> int drm_gem_shmem_madvise(struct drm_gem_object *obj, int madv);
>
> diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h
> index 128f88174d32..0c43b8f17ee9 100644
> --- a/include/drm/drm_gem_vram_helper.h
> +++ b/include/drm/drm_gem_vram_helper.h
> @@ -97,8 +97,8 @@ u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo);
> s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
> int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
> int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
> -void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo);
> -void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr);
> +int drm_gem_vram_vmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map);
> +void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map);
>
> int drm_gem_vram_fill_create_dumb(struct drm_file *file,
> struct drm_device *dev,
> --
> 2.28.0

Bit a big patch, I can't think of a way to split it up either.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation