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

4 files changed, 7 insertions, 7 deletions

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 9e8204be9a14..c6a1036bf2ea 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -157,7 +157,7 @@ static void compose_plane(struct vkms_composer *primary_composer,
 	void *vaddr;
 	void (*pixel_blend)(const u8 *p_src, u8 *p_dst);
 
-	if (WARN_ON(dma_buf_map_is_null(&primary_composer->map[0])))
+	if (WARN_ON(iosys_map_is_null(&primary_composer->map[0])))
 		return;
 
 	vaddr = plane_composer->map[0].vaddr;
@@ -187,7 +187,7 @@ static int compose_active_planes(void **vaddr_out,
 		}
 	}
 
-	if (WARN_ON(dma_buf_map_is_null(&primary_composer->map[0])))
+	if (WARN_ON(iosys_map_is_null(&primary_composer->map[0])))
 		return -EINVAL;
 
 	vaddr = primary_composer->map[0].vaddr;
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index d48c23d40ce5..18d944c57883 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -21,14 +21,14 @@
 #define YRES_MAX  8192
 
 struct vkms_writeback_job {
-	struct dma_buf_map map[DRM_FORMAT_MAX_PLANES];
-	struct dma_buf_map data[DRM_FORMAT_MAX_PLANES];
+	struct iosys_map map[DRM_FORMAT_MAX_PLANES];
+	struct iosys_map data[DRM_FORMAT_MAX_PLANES];
 };
 
 struct vkms_composer {
 	struct drm_framebuffer fb;
 	struct drm_rect src, dst;
-	struct dma_buf_map map[4];
+	struct iosys_map map[4];
 	unsigned int offset;
 	unsigned int pitch;
 	unsigned int cpp;
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index 32409e15244b..d8eb674b49a6 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 
-#include <linux/dma-buf-map.h>
+#include <linux/iosys-map.h>
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 8694227f555f..af1604dfbbaf 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 
-#include <linux/dma-buf-map.h>
+#include <linux/iosys-map.h>
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_fourcc.h>