dma-buf-map: Rename to iosys-map

Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's just a shim layer to abstract system memory, that
can be accessed via regular load and store, from IO memory that needs to
be acessed via arch helpers.

The idea is to extend this API so it can fulfill other needs, internal
to a single driver. Example: in the i915 driver it's desired to share
the implementation for integrated graphics, which uses mostly system
memory, with discrete graphics, which may need to access IO memory.

The conversion was mostly done with the following semantic patch:

	@r1@
	@@
	- struct dma_buf_map
	+ struct iosys_map

	@r2@
	@@
	(
	- DMA_BUF_MAP_INIT_VADDR
	+ IOSYS_MAP_INIT_VADDR
	|
	- dma_buf_map_set_vaddr
	+ iosys_map_set_vaddr
	|
	- dma_buf_map_set_vaddr_iomem
	+ iosys_map_set_vaddr_iomem
	|
	- dma_buf_map_is_equal
	+ iosys_map_is_equal
	|
	- dma_buf_map_is_null
	+ iosys_map_is_null
	|
	- dma_buf_map_is_set
	+ iosys_map_is_set
	|
	- dma_buf_map_clear
	+ iosys_map_clear
	|
	- dma_buf_map_memcpy_to
	+ iosys_map_memcpy_to
	|
	- dma_buf_map_incr
	+ iosys_map_incr
	)

	@@
	@@
	- #include <linux/dma-buf-map.h>
	+ #include <linux/iosys-map.h>

Then some files had their includes adjusted and some comments were
update to remove mentions to dma-buf-map.

Since this is not specific to dma-buf anymore, move the documentation to
the "Bus-Independent Device Accesses" section.

v2:
  - Squash patches

v3:
  - Fix wrong removal of dma-buf.h from MAINTAINERS
  - Move documentation from dma-buf.rst to device-io.rst

v4:
  - Change documentation title and level

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com

2 files changed, 5 insertions, 5 deletions

diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index 00bfa41ff7cb..9c8d56b0a41b 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -107,7 +107,7 @@ struct ast_cursor_plane {
 
 	struct {
 		struct drm_gem_vram_object *gbo;
-		struct dma_buf_map map;
+		struct iosys_map map;
 		u64 off;
 	} hwc[AST_DEFAULT_HWC_NUM];
 
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 956c8982192b..400845d4144c 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -801,11 +801,11 @@ ast_cursor_plane_helper_atomic_update(struct drm_plane *plane,
 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(new_state);
 	struct drm_framebuffer *fb = new_state->fb;
 	struct ast_private *ast = to_ast_private(plane->dev);
-	struct dma_buf_map dst_map =
+	struct iosys_map dst_map =
 		ast_cursor_plane->hwc[ast_cursor_plane->next_hwc_index].map;
 	u64 dst_off =
 		ast_cursor_plane->hwc[ast_cursor_plane->next_hwc_index].off;
-	struct dma_buf_map src_map = shadow_plane_state->data[0];
+	struct iosys_map src_map = shadow_plane_state->data[0];
 	unsigned int offset_x, offset_y;
 	u16 x, y;
 	u8 x_offset, y_offset;
@@ -883,7 +883,7 @@ static void ast_cursor_plane_destroy(struct drm_plane *plane)
 	struct ast_cursor_plane *ast_cursor_plane = to_ast_cursor_plane(plane);
 	size_t i;
 	struct drm_gem_vram_object *gbo;
-	struct dma_buf_map map;
+	struct iosys_map map;
 
 	for (i = 0; i < ARRAY_SIZE(ast_cursor_plane->hwc); ++i) {
 		gbo = ast_cursor_plane->hwc[i].gbo;
@@ -910,7 +910,7 @@ static int ast_cursor_plane_init(struct ast_private *ast)
 	struct drm_plane *cursor_plane = &ast_cursor_plane->base;
 	size_t size, i;
 	struct drm_gem_vram_object *gbo;
-	struct dma_buf_map map;
+	struct iosys_map map;
 	int ret;
 	s64 off;