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

1 files changed, 6 insertions, 6 deletions

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index ed43b987d306..e9a9d35fbf5e 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -373,7 +373,7 @@ static void drm_fb_helper_resume_worker(struct work_struct *work)
 
 static void drm_fb_helper_damage_blit_real(struct drm_fb_helper *fb_helper,
 					   struct drm_clip_rect *clip,
-					   struct dma_buf_map *dst)
+					   struct iosys_map *dst)
 {
 	struct drm_framebuffer *fb = fb_helper->fb;
 	unsigned int cpp = fb->format->cpp[0];
@@ -382,11 +382,11 @@ static void drm_fb_helper_damage_blit_real(struct drm_fb_helper *fb_helper,
 	size_t len = (clip->x2 - clip->x1) * cpp;
 	unsigned int y;
 
-	dma_buf_map_incr(dst, offset); /* go to first pixel within clip rect */
+	iosys_map_incr(dst, offset); /* go to first pixel within clip rect */
 
 	for (y = clip->y1; y < clip->y2; y++) {
-		dma_buf_map_memcpy_to(dst, src, len);
-		dma_buf_map_incr(dst, fb->pitches[0]);
+		iosys_map_memcpy_to(dst, src, len);
+		iosys_map_incr(dst, fb->pitches[0]);
 		src += fb->pitches[0];
 	}
 }
@@ -395,7 +395,7 @@ static int drm_fb_helper_damage_blit(struct drm_fb_helper *fb_helper,
 				     struct drm_clip_rect *clip)
 {
 	struct drm_client_buffer *buffer = fb_helper->buffer;
-	struct dma_buf_map map, dst;
+	struct iosys_map map, dst;
 	int ret;
 
 	/*
@@ -2322,7 +2322,7 @@ static int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper,
 	struct drm_framebuffer *fb;
 	struct fb_info *fbi;
 	u32 format;
-	struct dma_buf_map map;
+	struct iosys_map map;
 	int ret;
 
 	drm_dbg_kms(dev, "surface width(%d), height(%d) and bpp(%d)\n",